Abstract
Gender Score Construction Based on Retrospective Data Analysis in the Berlin Aging Study II (BASE-II)
A. Tauseef Nauman, MPH1, Nicholas Alexander, MPH2, Friederike Kendel3, Johanna Drewelies4, Gert G. Wagner5, Denis Gerstorf6, Ilja Demuth7, Louise Pilote8, and Vera Regitz-Zagrosek9
1Institute for Gender in Medicine, Charité—Universitätsmedizin Berlin, 2CCR Charité—Universitätsmedizin Berlin, DZHK (German Centre for Cardiovascular Research), partner site Berlin
2Berlin School of Public Health Charité—Universitätsmedizin Berlin, DZHK (German Centre for Cardiovascular Research), partner site Berlin PD
3Institute of Medical Psychology, Charité—Universitätsmedizin Berlin
4Department of Psychology, Humboldt-Universität zu Berlin
5SocioEconomic Panel at the German Institute for Economic Research (DIW)
6Department of Psychology, Humboldt-Universität zu Berlin PD
7Medical Clinic for Endocrinology, Biology of Aging group, Charité—Universitätsmedizin Berlin, Berlin-Brandenburg Center for Regenerative Medicine (BCRT), Charité University Medicine Berlin, Germany
8Department of Medicine, McGill University, 3DZHK (German Centre for Cardiovascular Research), partner site Berlin
9Institute for Gender in Medicine, Charité—Universitätsmedizin Berlin, CCR Charité—Universitätsmedizin Berlin, DZHK (German Centre for Cardiovascular Research), partner site Berlin
As intercultural differences may be an important factor in capturing the construct “gender,” we aimed to reconstruct a gender score comparable to the index published by Pilote (APS 2015) in a retrospective analysis of baseline data of Berlin Aging Study (BASE-II). We used data obtained in 2009 to 2014 of 1870 participants aged 60 years or above. From the psychosocial and gender-related variables, we selected 33 variables for reconstruction of a gender score. Principal component analysis (PCA) was performed to reduce the number of variables. Logistic regression models (LRA) were calculated, and nonsignificant variables were removed one by one in a descending order of their P value. Coefficient estimates of these variables associated with sex were used to calculate gender score on a scale of 0 to 100. At first a correlation analysis of 33 selected variables was conducted and in each significantly correlated pair one of the 2 variables were randomly removed. In total, 7 variables were removed in this step. In the second step of PCA, 26 variables were used. Five variables with too few cases were removed and remaining 21 variables loaded onto 9 components. One variable, loading equally high on 2 components was also removed. The 20 identified variables were used to perform the LRA. After calculating 4 models, 7 most significant variables for sex as an outcome variable were extracted (PSS composite, affection, Big Five-neuroticism, UCLA composite, hours per day on housework, family status, and Big Five-Extraversion). The coefficients of the final LRA were used to calculate the gender score (0-100). Gender score distribution was significantly different between women and men. The procedure enabled us to construct a gender score in a retrospective. In future, we will examine the validity of the score by linking differences in gender with psychosocial, medical, and cognitive data and by comparison with a prospectively assessed gender score.
Discrimination at the Medical University of Innsbruck (MUI)
Gloria Tauber1, Heidi Siller1, and Margarethe Hochleitner1
1Gender Medicine Unit, University of Innsbruck, Innsbruck, Austria
Effects of Myocytic Androgen Receptor Overexpression on Sexually Dimorphic Exercise Adaptations in Rats
Sabrina T. Barsky1 and Ashley Monks1
1University of Toronto, Mississauga, Ontario, Canada
In humans, exercise improves symptoms of various pathological states, although exercise adaptations seem to differ in response to sex. Skeletal muscle anabolism is thought to be regulated by androgen receptor (AR) through poorly specified mechanisms. Interactions of AR and exercise on muscle phenotype remain inconclusive in males and undetermined in females. We hypothesized that sex differences in exercise adaptations are regulated by the androgenic system and the type of exercise performed. Here, we examined interactions between a muscle-specific AR overexpression transgene (HSA-AR) and forced aerobic exercise on muscle and adipose exercise adaptation in male and female rats (N = 94). We replicated effects of HSA-AR on body composition, with males only having increased % lean mass and reduced % fat mass (P < .05). Aerobic exercise improved lean body phenotype significantly, with lesser indices of total and % fat mass (P < 0.01) in both sexes. Sex-specific effects of exercise included decreased total body mass (P < .01) in males and increased lean mass % (P < .001) in females. This varied response in total mass and lean mass according to exercise presents a sexually dimorphic response to exercise. Neither sex showed an interaction between HSA-AR and forced aerobic exercise on body composition. Future work is proposed to examine effects of exercise type (aerobic vs resistance) and the role of gonadal androgens in sexually dimorphic exercise-mediated mitochondrial adaptations. This work implicates the development of sex-specific exercise therapies.
Risk of Sexual and Reproductive Dysfunction After Mild Traumatic Brain Injury (mTBI)/Concussion in Women of Reproductive Age
Martina Anto-Ocrah, PhD, MPH, MT(ASCP)1,2, Jeff Bazarian, MD, MPH1,3,4, Vivian Lewis, MD2, Courtney Marie Jones, PhD, MPH1,3, Todd A. Jusko, PhD, MS3, and Edwin van Wijngaarden, PhD, MS3
1Department of Emergency Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
2Department of Obstetrics and Gynecology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
3Department of Public Health Sciences, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
4Department of Neurology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
Differential Impact of Co-Expressed SP-A1/SP-A2 Protein on AM miRNome
Nithyananda Thorenoor1, Xuesheng Zhang1, and Joanna Floros1,2
1Department of Pediatrics, Center for Host Defense, Inflammation, and Lung Disease (CHILD) Research
2Obstetrics & Gynecology, The Pennsylvania State University College of Medicine, Hershey, PA, USA
Surfactant protein A (SP-A) plays important role in lung innate immunity and surfactant-related functions under basal conditions and in response to various insults such as infection and oxidative stress. The human SP-A locus consists of 2 functional genes, SFTPA1 and SFTPA2, and one pseudogene. Each of the functional genes encodes human SP-A1 and SP-A2 proteins and each has been shown to have several genetic variants. SP-A interacts with alveolar macrophages (AM), the guardian cells of innate immunity, and regulates many of its functions under basal condition and in response to various insults. It has been shown that SP-A variants differ in their ability to regulate the AM miRNome in response to oxidative stress (OxS) as well as lung function mechanics and survival in response to bacterial infection. Because humans have both SP-A gene products, we were interested to determine the combined effect of co-expressed SP-A1/SP-A2 (coex) in response to ozone (O3)-induced OxS on AM miRNome. Human transgenic (hTG) mice, carrying both SP-A1/SP-A2 (6A2/1A0, coex) and SP-A–KO were utilized. The hTG and KO mice were exposed to filtered air (FA) and O3, and miRNA levels were measured after AM isolation with or without normalization to KO. We found (i) Significant differences in AM miRNome of coex in terms of sex, exposure, with or without normalization to KO, and after Bonferroni multiple comparison analysis; (ii) The AM miRNome of females to be significantly regulated in response to OxS compared to control (FA); (iii) Several of the mRNA targets that were significantly regulated by miRNAs to be involved in cell cycle, cellular growth, and proliferation as well as inflammatory response and cell-mediated immune responses; (iv) The AM SP-A2 miRNome to be similar to that of coex, when we compared the coex miRNome to that of hTG mice carrying either and SP-A1 or SP-A2 variant under the same condition, whereas the SP-A1 to differ from both (SP-A2 and coex). We observed previously that the single gene product SP-A2 had a major effect on the male AM miRNome in response to OxS, whereas no differences were observed in male coex (present study) indicating a differential role of single or both gene products in AM miRNome, and sex-specific differences in response to OxS. We speculate that the presence and/or relevant amounts of each gene product have a differential impact on males and females in response to various insults.
Serum Anti-Mullerian Hormone Levels and Measures of Arterial Stiffness
S. Dumanski, MD1,2,3,4, C. Kalenga, BSc2,3, S. Ramesh, PhD3, K. Nerenberg, MD1,2, A. Metcalfe, PhD1,5, J MacRae, MD1,2,4, D. Sola, RN2, and S. B. Ahmed, MD1,2,4
1Department of Medicine, University of Calgary, Calgary, Alberta, Canada
2Libin Cardiovascular Institute of Alberta, Alberta, Canada
3Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
4Alberta Kidney Disease Network
5Department of Obstetrics & Gynecology, University of Calgary, Calgary, Alberta, Canada
Abstract
Reduced female fertility is associated with increased cardiovascular (CVD) risk, though the mechanism remains unknown. Low serum anti-Müllerian hormone (AMH) levels are associated with increased risk of CVD, independent of age, and metabolic risk factors, though the pathophysiologic mechanisms underlying low AMH and CVD remain unclear. This study aimed to determine the association between AMH levels, the gold standard marker of fertility, and measures of arterial stiffness, a validated marker of CVD risk in healthy female and male humans. We hypothesize that AMH levels are inversely related to measures of arterial stiffness. An exploratory cross sectional study was performed in healthy premenopausal female and male participants in the high-salt state after an overnight fast. Female participants were studied in the low estrogen phase of the menstrual cycle and none were ingesting the oral contraceptive. Baseline demographic, metabolic data, and AMH levels were collected. Using standardized protocols, measurements of arterial stiffness (aortic augmentation index [AIX] and pulse wave velocity [PWV]) were determined using noninvasive applanation tonometry. Linear regression analyses were employed to evaluate the association between AMH levels and measures of arterial stiffness. Twenty-nine female (age 30.8 ± 8.5 years, 66% Caucasian) and 19 male (age 37.3 ± 13.0 years, 74% Caucasian) participants were studied. All subjects were normotensive and nondiabetic. Female subjects demonstrated a negative association between AMH and AIX (R 2 = 0.15, P = .03), though no association was observed between AMH levels and PWV (R 2 = 0.03, P = .41). No relationship was observed between AMH and arterial stiffness in the male participants. Lower AMH levels are associated with increased arterial stiffness in female but not male subjects, suggesting a direct role of AMH in vascular homeostasis in females. AMH may provide a potential novel therapeutic target for CVD prevention in women.
Rapid Activation of Cell Signaling Cascades by 17b-Estradiol in the Dentate Gyrus of Adult Rats
Paul A. S. Sheppard1 and Liisa A. M. Galea1
1University of British Columbia, British Columbia, Canada
In addition to the classical, genomic effects of estrogens, rapid effects involving activation of cell signaling cascades have been observed. Many of the rapid effects of estrogens within the hippocampus of rodents have been found to be dependent upon cell signaling cascades (Sheppard et al, 2018; Frick et al, 2018). Whether these pathways are rapidly activated within the dentate gyrus by estrogens has yet to be determined. Cell proliferation within the dentate gyrus is increased 30 minutes (Barha et al, 2009; Duarte-Guterman et al, 2015) or 2 hours (Tanapat et al, 1999) following systemic 17b-estradiol (E2) administration in ovariectomized (OVX) female rats, suggesting that rapid, likely nongenomic mechanisms may underlie these effects. Whether these E2-mediated increases also occur in males remains to be determined. Importantly, sex differences exist in the rapid activation of hippocampal cell signaling cascades in response to estrogens (Koss et al, 2018). Here, gonadally intact male and female rats (estrous phase determined via lavage) and OVX female rats were given a subcutaneous injection of either 0.3 or 10 µg of E2 (in 0.1 mL oil) or vehicle (oil). These doses were chosen as they increase cell proliferation in the dentate gyrus of OVX female rats (Barha et al, 2009; Duarte-Guterman et al, 2015) and result in circulating levels of E2 observed during diestrus and proestrus, respectively (Viau & Meaney, 1991). Thirty minutes later, rats were killed, and their brains were flash frozen for protein analyses. Using a multiplex electrochemiluminescent reader, we measured levels of phosphorylated extracellular signal-regulated protein kinase (ERK), phosphoinositide 3-kinase (PI3 K), c-Jun N-terminal kinase (JNK), p38, Akt, glycogen synthase kinase 3 beta (GSK-3b), and ribosomal protein S6 kinase (p70S6 K) in the dentate gyrus. In this way, we can determine what pathways are rapidly activated by E2 and may be involved in the rapid effects of E2 on cell proliferation.
Widespread Sexual Dimorphism in the Transcriptome of Human Airway Epithelium in Response to Smoking
Ma’en Obeidat1, Chen Xi Yang1, Henry Shi1, Irving Ding1, Cheng Wei1, Tony Yang1, and Don D. Sin1
1The University of British Columbia, Vancouver, British Columbia, Canada
Epidemiological studies have shown that female smokers are at higher risk of chronic obstructive pulmonary disease (COPD). Female patients have worse symptoms and health status and increased risk of exacerbations. We hypothesized that sex-specific transcriptomic changes in airway epithelium in response to smoking can explain the biological mechanisms underlying the sexually dimorphic COPD presentation. We determined the differences in the transcriptome of the airway epithelium between males and females at baseline and in response to smoking. We processed public gene expression data from the Gene Expression Omnibus (GEO) of human airway epithelium into a discovery cohort of 211 subjects (never smokers n = 68; current smokers n = 143) and 2 replication cohorts of 104 subjects (21 never, 52 current, and 31 former smokers) and 238 subjects (99 current and 139 former smokers). We analyzed gene differential expression with smoking status, sex, and smoking-by-sex interaction and used network approaches for modules’ level analyses. We identified and replicated 2 differentially expressed modules between the sexes in response to smoking with genes located throughout the autosomes and not restricted to sex chromosomes. The 2 modules were enriched in autophagy (upregulated in female smokers) and response to virus and type 1 interferon signaling pathways which were downregulated in female smokers compared to males. The results offer insights into the molecular mechanisms of the sexually dimorphic COPD risk and presentation potentially enabling a precision medicine approach to COPD. While smoking has a large effect on the transcriptome of airway epithelium, it differentially affects the viral response and autophagy pathways in female smokers compared to males. Such differential expression may explain the increased risk for disease and exacerbation among female smokers.
Sex Hormones and Sex of the Cell in Human Kidney Metabolism. Implications for Chronic Kidney Disease
Sergi Clotet1, Julie Van1, Aman Mehrotra2, Adam Gehring2, Minna Woo3, Amy Caudy4, and Ana Konvalinka1
1Division of Nephrology, Department of Medicine, University Health Network of Toronto, Ontario, Canada
2Department of Immunology, University of Toronto, Toronto, Ontario, Canada
3Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
4Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
Low Frequency Corticostriatal Oscillations Predict Alcohol Drinking Behavior in Male and Female Rats
Angela M. Henricks, PhD1, Emily D. K. Sullivan2, Lucas L. Dwiel2, Alan I. Green, MD1, and Wilder T. Doucette, MD/PhD1
1Geisel School of Medicine at Dartmouth, Hanover, NH, USA
2Program in Experimental and Molecular Medicine at Dartmouth, Hanover, NH, USA
There are significant sex differences in the patterns of alcohol use in humans, as well as in rodent models of alcohol consumption. However, the neurobiology underlying these sex differences is poorly understood. We hypothesized that local field potential (LFP) oscillations in corticostriatal circuits may contain information regarding sex differences in alcohol drinking behavior in rodents. Adult male and female Sprague-dawley rats were implanted with bilateral electrodes targeting the nucleus accumbens shell, and prelimbic and infralimbic cortex. Following recovery, LFPs were recorded from each rat during two, 30-minute sessions, and then during five, 90-minute sessions while rats had access to 10% alcohol. Using the machine-learning algorithm lasso, we then built models to predict: (1) biological sex (“trait” differences); and (2) when a rat was drinking alcohol versus not drinking alcohol from corticostriatal LFPs. We compared the model performance from real data to the performance of models built and tested on data permutations. As predicted, female rats drank more alcohol than males across sessions (P < .05). Additionally, models built from the real data were able to outperform models built from data permutations in predicting biological sex (71% ± 5% vs 55% ± 9%) and when a rat was drinking alcohol versus not drinking alcohol (91% ± 0.03% vs 49% ± 0.07% for males; 91% ± 0.1% vs 49% ± 0.1% for females). Low frequency oscillations (1-4 Hz) contained the majority of the neural information contributing to the latter model’s accuracies in both sexes. These data suggest that while there are inherent “trait” differences in corticostriatal activity between sexes, corticostriatal activity features that are associated with alcohol drinking behavior are similar across sexes. Moreover, low frequency oscillations from corticostriatal regions may serve as a neural target for future therapeutic development aimed at reducing alcohol consumption in males and females.
Sex and Inhibition: Sex-Specific Differences in the Development of the Hippocampal GABAergic Network
Daniele C. Wolf1, Nathalie T. Sanon2, Tarek Shaker1, Abdul-Rahman Elhassan2, Antônia do Nascimento2, Lionel Carmant1, Graziella di Cristo1, and Alexander G. Weil1
1Université de Montréal, Montreal, Québec, Canada
2Centre Hospitalier Universitaire CHU-Sainte-Justine
Sexual differentiation of the brain is influenced by testosterone (T) and its metabolites during the perinatal period in males (♂) and females (♀). This period is also critical for GABAergic network maturation and may be involved in T♀ susceptibility to seizures. Similar happens to ♂ but it is unlikely in ♀, according to our epilepsy model. Since T (endo-or-exogenous) might be involved in brain excitability, we aim to understand the development of the GABAergic network in nonepileptic rats, not only in ♂ and ♀ rats, but also in T♀ and T-insensitive ♂ rats. Sexual morphological and hormonal parameters were accessed during development. Protein expression of the chloride cotransporter KCC2 was evaluated in the hippocampus at postnatal days (P) 3, 7, and 40, whereas its membrane protein fraction was analyzed at P7. Functional consequences of KCC2 expression were determined by spontaneous inhibitory postsynaptic currents (sIPSCs) recorded in CA1 pyramidal cells. We found strong effects of circulating T levels on sexual phenotypes (absence of nipples and anogenital distance). Levels of T were significantly lower in ♀ (P < .0001), whereas estradiol levels were similar between sexes. KCC2 protein expression was not significantly different between sexes, however ♀ have higher membrane KCC2 levels compared to ♂ (P = .0007) and T♀ (P = .0071) at P7. Cumulative probability plot showed increased sIPSC amplitude in CA1 pyramidal cells of ♀ compared to ♂ (P < .0001) and higher sIPSC amplitude and frequency in cells of T-insensitive ♂ compared to ♂ (P < .0001). Thus far, we show phenotypical and physiological differences between sexes, namely in KCC2 levels and the frequency and amplitude of inhibitory currents, suggesting probable involvement of T in cell excitability. Further analysis of the GABAergic system in these sex conditions will help to understand the sex-specificity of epileptogenesis.
Mechanistic Understanding of Structural and Molecular Differences in Female and Male Human Pluripotent Stem Cells and Their Effects on Differentiation Process Toward Cardiac Cells
Morteza Mahmoudi1
1Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
Over the past decade, the majority of efforts in myocardial regeneration have been centered on cell-based cardiac repair. However, the mechanistic understanding on the potential effects of cell sex in cell therapy is ignored. We have recently discovered significant cytoskeletal variations in male and female human amniotic stem cells. Here, we hypothesized that an in-depth analysis of the possible structural differences between male and female human pluripotent stem cells (hiPSCs) and their effects on the differentiation process toward cardiac cells is required to provide a unique opportunity for advancing cell therapy for cardiac repair in both sexes. Using a wide range of techniques, we revealed substantial differences in male and female’s cytoskeletal features including their actin filaments, microtubules, and lamin B structures. These cytoskeletal variations have a capacity to dictate differentiation process through the mechanotransduction effects on cell nucleus and chromatin conformation. We used chemically defined approach to differentiate male and female hiPSCs (400 total trials—200 per each cell sex) and found out that 59% and 87% of batches from male and female cells (respectively) ended up with beating cells. In addition, the female cells demonstrated a significantly higher amount of differentiated cardiac cells compared to the male cells in each batch. Quantitative polymerase chain reaction (qPCR) were used to probe the male and female cell differences in expression of genes relevant to cardiac maturity, contractility, and Ca2+ transport (eg, TNNT2, MYH6, MYH7, and CACNA1c) and the outcomes revealed substantially higher expression of 5 maturation genes in cultured female cells on the multiscale substrates compared to the male ones. Our results may pave a way to better address the public health epidemic on the considerable effects of sex on cardiac disease and heart failure.
Gender Differences in Pursuing Leadership Positions in the Netherlands; A Study in Cardiovascular PhD Candidates
Elise L. Kessler, PhD1, Birgit Goversen, MSc2, and Hester M. den Ruijter, PhD1
1Laboratory of Experimental Cardiology, Division of Heart & Lungs, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
2Division of Heart & Lungs, Department of Medical Physiology, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
Science benefits from gender diversity. In the Netherlands, (bio)medical master programs currently enroll more female than male students, but scientific leadership positions are still mainly occupied by men. Women refrain from academic careers—referred to as the “leaking pipeline phenomenon”—and reasons are, for example, family planning or glass-ceiling. In the Netherlands, women start working part-time even before family planning comes into play. To be able to promote academic careers among women, we have to know their intrinsic motivation and adapt the initiatives accordingly. Therefore, 143 PhD candidates (32% male and 68% female) of Dutch cardiovascular research programs participated in an online questionnaire (which was not mentioned to be used for gender studies) to evaluate the intrinsic motivation of PhD candidates on pursuing a leadership position. In this questionnaire, 29% of all female and 46% of all male PhD candidates responded that they would aim for a leadership position, which we define as full professor, dean, corporate executive officer, (medical) group leader, and so on. Of all female candidates, 40% could imagine having a leadership position in the future compared to 63% of male candidates. Besides that, 39% of all female and 30% of all male PhD candidates were not sure; and 20% of all women, but only 7% of men could not imagine having a leadership position in the future. When asked whether a certain initiative would positively influence their decision to pursue a leadership position, 89% of women and 78% of men would like a permanent contract and 70% of women and 63% of men would proceed toward leadership, if success was not measured by impact factor. Interestingly, women did not respond positively to gender-specific initiatives, since only 13% and 12% would be positively influenced by female-specific grants or a female-quota, respectively. Free day care for children would persuade 67% of women and 43% of men and possibilities for a part-time position would persuade 73% of women and 59% of men to pursue a leadership position. Less female cardiovascular PhD candidates in the Netherlands aim at or can imagine having a leadership position compared to male candidates. However, women reported that position certainty and alternative measures of impact would motivate them to pursue a leadership position rather than gender-specific initiatives.
Temporal trends in cardiovascular hospitalization rates following the onset of ESKD by sex.
Exposure to an Obesogenic Diet Prevents Differences in Calorie Intake Across Phases of the Estrous Cycle and Stimulates Weight Gain in Female Rats
Jamie E. Coborn, PhD1,2, Jeffrey C. Yu3, Ashley C. Flores4, Victoria R. Snapp5, and Jennifer A. Teske, PhD6,7
1Mary Horrigon Connors Center for Women’s Health & Gender Biology, Brigham and Women’s Hospital, Boston, MA, USA
2Department of Psychiatry, Harvard Medical School, Boston, MA, USA
3Department of Neuroscience, University of Arizona, Tucson, AZ, USA
4Undergraduate program in Neuroscience and Cognitive Science–School of Mind, Brain and Behavior, University of Arizona, Tucson, AZ, USA
5Department of Physiology, University of Arizona, Tucson, AZ, USA
6Department of Nutritional Science, University of Arizona, Tucson, AZ, USA
7Department of Food Science and Nutrition, University of Minnesota, Minneapolis, MN, USA
Insufficient sleep promotes obesity. Yet women are more likely to be obese and self-report poor sleep compared to men. Rodent studies are advantageous for studying sex differences in weight gain due to insufficient sleep since they can be conducted in a more controlled setting and sleep and energy expenditure (EE) can be precisely determined. Yet, including female rats adds complexity since the rhythmicity of sex steroids (estrogen, progesterone, etc) across the estrous cycle affects sleep, weight gain, and food intake. While proestrus has the greatest influence, it’s unclear whether other factors that modify bodyweight differ across phases of the estrous cycle. We tested the hypothesis that physical activity (PA), total EE, and its components would be phase dependent and feeding palatable diets would stimulate weight gain and prevent the effect of phase on calorie intake. To test this, EEG, EMG, PA, total EE, and its components (eg, EE during PA, NREM, and REM sleep = EEPA, EENREM, EEREM) were determined from 3-month-old female Sprague-Dawley rats (N = 6) for X days. In a separate set, food intake and weight gain were measured for 9 days in female rats (N = 48) fed rodent chow ad lib, chocolate (3 h/d+chow 21 h/d), cafeteria-style diet (CAF, 3 h/d + chow 21 h/d), or CAF ad lib. CAF = rotating selection of 24 human foods (eg, chips, cookies, hot dogs, etc). PA, EE, and EEPA was significantly higher while EENREM and EEREM was significantly lower in proestrus relative to all phases. CAF stimulated weight gain and hyperphagia. Calorie intake was significantly lower in proestrus relative to all phases with chow or chocolate. Cafeteria-style diet prevented phase-dependent differences in calorie intake and caused hyperphagia during proestrus. Thus, like sleep, other factors that modulate bodyweight including PA and components of EE are phase dependent and feeding an obesogenic diet disrupts the effect of phase on calorie intake, which would be expected to contribute to weight gain during insufficient sleep.
Examining the Impact of Neuroimmune Dysregulation on Social Behavior in Male and Female Juvenile Rats
Alexandra Turano1, Elizabeth M. McAuley1, Nicole A. Haas1, and Jaclyn M. Schwarz1
1University of Delaware, Newark, DE, USA
Autism is characterized by impaired social interactions, inadequate verbal/nonverbal communication, restricted interests, and stereotyped behaviors. But, the biological causes of these symptoms remain inconclusive. In addition to genetic factors, epidemiological data indicate that environmental factors also contribute to the risk of autism. Neonatal exposure to infectious pathogens is one of these environmental factors, suggesting that activation of the neonatal immune system may contribute to autism pathology. Microglia, the resident immune cells of the brain, perform functions crucial for normal brain development and behavior. According to a “two-hit model of neuroinflammation,” neonatal neuroimmune activation causes persistent deficits in microglial functioning, resulting in an exaggerated immune response and significant behavioral deficits following subsequent immune activation later in life. Importantly, males are more likely than females to be diagnosed with autism. During early development, males and females exhibit different microglial phenotypes, possibly leaving males more susceptible to the negative outcomes associated with early-life neuroinflammation. Moreover, there is evidence to suggest that structures within the “social behavior neural circuit” are sexually dimorphic. Therefore, our goal was to better understand the impact of neuroimmune dysregulation on the development and expression of social behaviors in male and female rats. We first piloted behavioral paradigms to characterize social behavior development in juvenile rats, and then applied the two-hit model of neuroinflammation to determine how immune activation may affect the expression of these social behaviors. We concurrently measured cytokine expression in the male and female juvenile brain. These experiments may help to elucidate when and how a specific environmental risk factor contributes to behavioral outcomes associated with autism, and the sex-specific nature of that risk factor.
Neonatal Ventral Hippocampal Lesion Leads to Increased Alcohol Consumption in Adult Male and Females Rats
Emily D. K. Sullivan1, Jibran Y. Khokhar2, Alan I. Green1
1Department of Psychiatry, Dartmouth-Hitchcock Medical Center, Geisel School of Medicine, Hanover, NH, USA
2Department of Biomedical Sciences, University of Guelph, Guelph, Ontario, Canada
Alcohol use disorder (AUD) affects approximately 40% of men and women with schizophrenia (SCZ), ultimately exacerbating medical and psychiatric morbidity. In general, men with SCZ are more prone to AUD than are women. The neonatal ventral hippocampal lesion (NVHL) rat model mimics many of the cognitive symptoms of SCZ and, when exposed to alcohol in adolescence, males show increased alcohol consumption in adulthood. The current project sought to explore whether female NVHL rats also display increased alcohol drinking behavior similar to males, and begin to explore whether the NVHL model might serve as a mechanism by which to study sex differences in SCZ and comorbid AUD. NVHL or sham lesion rats were created by bilaterally injecting ibotenic acid or vehicle into the ventral hippocampi of male and female Sprague-Dawley rats on postnatal day (PD) 7 (n = 8-19/group). All rats were given continuous access to 10% ethanol from PD 28-42 via a 2-bottle choice paradigm. Beginning on PD 90, rats received continuous access to 20% ethanol via 2-bottle choice paradigm until stable. Regardless of sex, NVHL rats drank more alcohol in adulthood compared to sham rats (P = .009 for males; P = .004 for females). However, repeated measures ANOVAs revealed that the temporal pattern of alcohol consumption between the sexes was different. Alcohol intake in male rats did not differ until week 5 after which NVHL males increased their consumption levels; by contrast, alcohol intake was higher in female NVHL rats compared to sham rats until week 13 when NVHL females reduced drinking to sham levels. These data suggest that disrupting normal hippocampal development, along with exposure to alcohol during adolescence, results in an increased preference for alcohol in adulthood for both male and female animals. However, male and female NVHL rats appear to have different temporal patterns of alcohol consumption, illuminating the importance of studying both sexes.
Long-Term Consequences of Severe Food Restriction on the Heart of Female Fischer Rats
Aline M. A. de Souza1, Crystal West1, Hong Ji1, Nataliia V. Shults2, Yuichiro J. Suzuki2, and Kathryn Sandberg1
1Department of Medicine, Georgetown University, Washington, DC, USA
2Department of Pharmacology and Physiology, Georgetown University, Washington, DC, USA
Individuals with body weight loss due severe food restriction (sFR) are at increased risk for developing cardiovascular disease during the sFR period. Patients present long QT interval, arrhythmia, hypotension, bradycardia, and sometimes death, which is primarily due to heart failure. Unfortunately, little is known about the heart function when these individuals recoveries the body weight. We investigated the consequences of sFR on heart structure and function. Female Fischer rats with 3-month-old were divided in control (CT; n = 18) and sFR (60% reduction of daily food intake, n = 18) group. After 2 weeks, all rats received regular chow ad libitum for 3 months. The rats were infused with vehicle (n = 8), or a bolus infusion of angiotensin II (400 ng/Kg – 0.2 mL; n = 6), or subjected to ischemia-reperfusion using a Langendorff preparation (n = 4). After 14 of sFR, body weight (BW; P = .02), mean arterial pressure (P = .03), heart rate (P = .03), and wet heart weight (P = .009) were reduced. At 3 months of refeeding, BW, MAP, HR, and wet heart weight were the same as CT. At 3 months of refeeding, the myocardium tissue revealed that parallel orientation of myofiber and clear striations present in normal cardiomyocytes were lost in sFR-refed animals. Uneven blood-filling of the vessels of the microcirculatory and prominent interstitial edema of the myocardium was observed. The cardiomyocytes were polymorphic and atrophied. Infusion of angiotensin II to sFR-refed animals resulted in focal necrotic lesions. The magnitude of ischemia/reperfusion-induced damage was also greater in sFR-refed animals compared to CT in Langendorff preparations. Despite normalization of body weight, blood pressure, heart rate, and wet heart weight after 3 months of refeeding, the hearts from animals subjected to severe food restriction are severely damaged. These findings suggest individuals who have recovered from prior exposure to a period of sFR are at increased risk of developing cardiovascular disease.
Rat Model of Prenatal Zika Virus Infection
Morgan L. Sherer, BS1, Pragyan Khanal, BS1, Mark Parcells, PhD2, and Jaclyn M. Schwarz, PhD1
1Department of Psychological and Brain Sciences, University of Delaware, Newark, DE, USA
2Department of Animal and Food Sciences, University of Delaware, Newark, DE, USA
Zika virus (ZIKV), a mosquito-borne flavivirus, has been associated with microcephaly and other neurological disorders in infants born to infected mothers. Despite being declared an international emergency by the World Health Organization, comparatively very little is known about the pathogenesis, mechanisms, or behavioral consequences of maternal ZIKV infection in the offspring. Our lab is interested in developing a working animal model to answer some of these questions. Here, we use a rat model of prenatal ZIKV infection to measure the level of infectivity, as well as the rate of viral clearance in both the mother and her pups. We examine various aspects of brain development in pups, including cortical thickness, microglia morphology, apoptosis, and neurogenesis. Given that pregnancy is associated with significant immunomodulation, we are also interested in the role that pregnancy has on the impact of ZIKV infection, therefore we compare viral infectivity between both pregnant and nonpregnant female rats. In this study, we show that prenatal ZIKV infection results in an increase in cell death and reduces hippocampal and cortical volumes in the neonatal rat brain. For the first time, we demonstrate the efficacy and validity of a rat model for maternal ZIKV infection with vertical transmission to the fetus. This model will allow us to (1) better understand the mechanisms underlying ZIKV infection and transmission to the fetus, (2) determine the impact of ZIKV infection on the developing male and female fetal brain, and (3) in the future, measure behavioral deficits and investigate potential sex differences associated with fetal ZIKV infection later in life.
The Effects of Early and Late Onset Oral Contraceptive Use on Structural Brain Changes in Women
Rupali Sharma1, Samantha Smith1, Aisa Dordari2, Andra Smith1, and Nafissa Ismail1
1University of Ottawa, Ottawa, Ontario, Canada
2Carleton University, Ottawa, Ontario, Canada
Millions of women worldwide use oral contraceptives (OCs), often starting at a pubertal age when their brains are in a crucial developmental stage. For girls, puberty marks the transition to womanhood whereby the surge of ovarian hormones confers reproductive competence and initiates brain reorganization that gives rise to the social, emotional, and cognitive development across adolescence. The influx and fluctuations of ovarian hormones in women contribute to sex differences in mood disorders, as women are disproportionately affected. Given that OCs modulate internal hormone production and that the age of first OC onset is decreasing toward early- to mid-puberty due to their marketability as “regulators,” examining the influence of hormonal OCs on women’s brain structure, function, and mood is warranted. Very little is known about OC effects on the brain and whether there are long-term neurological impacts of using OCs during puberty. Therefore, the objective of the current study was to examine the effects of early- and late-onset OC use and the natural menstrual cycle on total and regional grey matter (GM) and white matter (WM) volume changes. We hypothesized OC use would alter regional GM volume and increase regional WM volume compared to naturally cycling (NC) women. We also hypothesized there would be differences between early- and late-onset users, as age of onset/duration of OC use has not been accounted for in the existing literature. To test these hypotheses, undergraduate women (N = 75) underwent structural magnetic resonance imaging. Preliminary results via the SPM software show that NC women display larger GM volume in the left precentral gyrus, T(1,35) = 5.35, Pcorr < .05, but OC users show larger WM volume in the right insula, T(1,34) = 3.99, Pcorr < .05. The findings of the current study advance our understanding of how OCs impact the brain, especially during pubertal onset, and are relevant to women’s health at both individual and societal levels.
Adipose Extracellular Vesicles Derived From Female Lipoaspirate Inhibit Viral Myocarditis: Potential New Therapy
Damian N. Di Florio1, Katelyn A. Bruno, PhD1, Anneliese R. Hill1, Ming Tian2,3,4, Joy Wolfram, PhD2,3,4, and DeLisa Fairweather, PhD1
1Department of Cardiovascular Medicine, Mayo Clinic, Jacksonville, FL, USA
2Department of Transplantation Medicine, Mayo Clinic, Jacksonville, FL, USA
3Department of Physiology, Mayo Clinic, Jacksonville, FL, USA
4Department of Biomedical Engineering, Mayo Clinic, Jacksonville, FL, USA
Myocarditis is an autoimmune heart disease commonly caused by viral infections and can progress to dilated cardiomyopathy (DCM) and heart failure. In patients and mice, males develop more severe disease and are more likely to progress to DCM heart failure than females. The mechanisms underlying the sex differences in disease are not fully understood. Because matured cardiomyocytes do not have regenerative properties, damage caused by viruses and the immune response leaves clinicians with few treatment options. Regenerative medicine holds promise for novel therapies utilizing stem cells, extracellular vesicles, and conditioned media, for example. In this study, adipose-derived extracellular vesicles (AEVs) were obtained from the lipoaspirate of a postmenopausal woman. Based on previous studies of EV therapy, we injected wild type BALB/c male mice with 250 mL of AEVs (1 × 1010 EV/mL) intraperitoneally or sucrose control on day −1, 0, 1 with viral infection on day 0. Mice were harvested on day 10 post infection at the peak of myocarditis. We found that mice treated with AEVs had a significantly higher body weight (P = .0003), less calcification in the gut (P = .001), and less myocardial inflammation (P = .007) than controls indicating that AEVs were protective. These data suggest that AEVs may be a novel treatment for acute viral myocarditis, a disease with few treatment options.
Headache Prevalence in Transgender Youth: A Retrospective Chart
Jennifer A. Hranilovich, MD1, Kate Millington, MD2, Yee-Ming Chan, MD, PhD2, and Elizabeth Loder, MD, MPH1
1John R. Graham Headache Center, Department of Neurology, Brigham and Women’s Faulkner Hospital, Boston, MA, USA
2Division of Endocrinology, Department of Pediatrics, Boston Children’s Hospital, Boston, MA, USA
A sex difference in migraine prevalence arises in adolescence, peaking during mid-life with a female to male prevalence ratio of roughly 2. There is likely a hormonal contribution given its occurrence during reproductive years. Some research suggests that low testosterone (T) is associated with higher rates headache in males. We hypothesized that adolescents assigned male gender and given estrogen (E) as gender affirmation treatment will have a higher prevalence of headache than those with gender dysphoria who have not received E. We also hypothesized that adolescents assigned female gender and given T will have a higher prevalence of headache than those who are untreated. All patients from 2007 to 2017 seen in the Gender Management Service (GeMS) clinic at Boston Children’s Hospital were included. Data were collected on assigned gender and patients’ treatment with sex steroids by GeMS. Patients with headache diagnosis in their chart were identified and charts validated by JAH. Statistical testing was a χ2 analysis in Excel software. Results demonstrated that in those assigned male gender and treated with E, 6 (5%) of 119 had headache. In those assigned male gender and untreated, 3 (2%) of 150 had headache. In those assigned female gender and treated with T, 20 (9%) of 221 had headache. In those assigned female gender and untreated, 10 (4%) of 255 had headache. There was a statistically significant difference (P = .001) between expected and actual frequencies of headache in both comparisons. However, headache prevalence was higher in both E and T treatment groups compared with untreated groups. There are limitations to this study, including the small number of subjects, the retrospective nature of the study, and lack of a specific information about headaches. Our findings suggest that headache prevalence in transgender youth should be studied prospectively as the number of adolescents treated with gender affirmation hormones increases.
Targeted Neuroepigenetic Editing in Trauma Related Disorders
Ajinkya Suresh Sase1, Brandon A. Santhumayor1, Sonia I. Lombroso1, Rozalyn R. Wood1, and Elizabeth A. Heller1
1University of Pennsylvania, Philadelphia, PA, USA
Sex-differences in the expression and prevalence of mood disorders, such as post-traumatic stress disorder (PTSD), have led to a growing interest in the sex-specific molecular and epigenetic mechanisms underlying these diseases. Cyclin-dependent kinase 5 (Cdk5) is known to regulate such behaviors and magnitude of these behaviors. We recently showed that Cdk5-targeted histone acetylation in hippocampal region CA1 attenuates fear memory retrieval in female, but not male, mice. Although there is much evidence on the function of Cdk5 protein, very little is known about the sex-specific regulation of Cdk5 gene expression particularly in trauma-related disorders. We hypothesize that histone modification(s) of Cdk5 is sufficient to regulate its expression, and influence sexually dimorphic behavioral responses in fear memory. We used fear conditioning to study fear memory as it is a robust translational paradigm used in many cases to elucidate fear-related mechanisms of PTSD, such as fear extinction, fear inhibition, and generalization of fear. To this end, we used CRISPR-dCas9 based system to deliver histone modifying enzymes at Cdk5 promoter in neuroblastoma cells. We designed and screened multiple guide RNA’s targeted at Cdk5 promoter that modified the epigenetic landscape and regulated its expression. Next, we confirmed the enrichment of histone modifications at the Cdk5 promoter by CRISPR-dCas9. Viral expression of CRISPR-dCas9 fused with histone modifying enzymes in vivo targeting Cdk5 promoter was paired with fear conditioning and expression of CDK5. This work will provide a model of trauma evoked chromatin remodeling at Cdk5, and reveal the causal relevance of Cdk5 transcriptional regulation to trauma-induced behavior. The identification of such precise mechanisms in trauma mediated gene expression is necessary for the development of targeted therapeutic treatments.
TRPC6 Knock-Out Reverses Doxorubicin-Induced Cardiotoxicity and Cardiomyopathy in Mice
Carolina Morales-Lara, MD1, Katelyn A. Bruno, PhD1, Zacharias Anastasiadis2, Carolyn Landolfo, MD1, Nadine Norton, PhD2, and DeLisa Fairweather, PhD1
1Department of Cardiovascular Medicine, Mayo Clinic, FL, USA
2Department of Cancer Biology, Mayo Clinic, FL, USA
Doxorubicin is a chemotherapeutic drug associated with cardiotoxicity. However, preventive treatments are currently lacking. A GWAS conducted in patients from the N9831 clinical trial identified genetic variants of TRPC6 associated with lower left ventricular ejection fraction (P = 1.6 × 10− 6) indicating worse cardiac function. TRPC6 is an ion channel expressed in the heart and chronic activation promotes cardiac damage. We hypothesize that inhibiting TRPC6 should prevent doxorubicin-induced cardiotoxicity and cardiomyopathy. We found that inhibition of TRPC6 in human iPSC-derived cardiomyocytes reduced doxorubicin-induced apoptosis in culture (P <.0001). We injected B6129S wild-type (WT) and TRPC6 knock-out (KO) male and female mice (n = 20/group) intraperitoneally with saline or doxorubicin 6× for a 24 mg/kg cumulative dose and harvested at day 14 and 21. Echocardiography was performed at day 21. We found decreased heart weight (HW; P = .008) and increased cardiac vacuolation (P < .001) in male WT mice treated with doxorubicin compared to controls, which indicates cardiac damage/toxicity. HW was restored in doxorubicin-treated male mice when TRPC6 was knocked-out (P = .005). This effect on HW was not observed in TRPC6 KO female mice. Additionally, doxorubicin increased cardiac vacuolation in female WT mice (P < .0001) which was reduced in TRPC6 KO females (P = .03), similar to males. However, vacuolation was significantly higher in WT males treated with doxorubicin compared to WT females (P < .0001). A significant decrease in stroke volume (P = .007), diastolic volume (P = .01), and cardiac output (P = .004) was found at day 21 in WT males treated with doxorubicin compared to controls. This decrease in cardiac function was reversed in TRPC6 KO males. Our results found that cardiac damage after doxorubicin treatment was more severe in male than female mice and suggest that TRPC6 inhibition could be a novel therapy to prevent doxorubicin-induced cardiotoxicity and cardiomyopathy.
Hypertensive Disorders of Pregnancy Are Related to Higher Risk of Subsequent Hypertension, Higher Left Ventricular Mass, and Myocardial Scarring: A Report From the Women’s Ischemia Syndrome Evaluation-Coronary Vascular Dysfunction Study
Odayme Quesada1, Ki Park2, Janet Wei1, Eileen Handberg2, Chrisandra Shufelt1, Margo Minissian1, Galen Cook-Wiens3, Parham Zarrini1, Christine Pacheco1, Louise E. Thomson4, Daniel S. Berman4, Carl J. Pepine2, and C. Noel Bairey Merz1
1Barbra Streisand Women’s Heart Center, Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
2Division of Cardiovascular Medicine, Department of Medicine, University of Florida, Gainesville, FL, USA
3Biostatistics and Bioinformatics Research Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA
4Mark S. Taper Imaging Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA
Sex Differences in Metabolism Reveal a Unique Role for Glutamine in Male Glioblastoma
Jasmin Sponagel, Shanshan Zhangl, Prakash Chinnaiyan, MD2, Josh B. Rubin, MD, PhDl, and Joseph Ippolito, MD, PhDl
1Washington University in St Louis School of Medicine, St Louis, MO, USA
2Oakland University William Beaumont School of Medicine, Auburn Hills, MI, USA
Glioblastoma (GBM) is the most common and aggressive brain tumor in adults. Glioblastoma occurs more commonly in males but female patients survive significantly longer. Understanding the molecular mechanisms that underlie those sex differences is a promising approach for the development of novel treatment strategies. In our efforts to identify the mechanisms underlying these differences, we found that male and female GBM differ in their metabolite abundance and that male patients exhibit a significantly higher abundance of glutamine. In order to investigate the contribution of glutamine metabolism to sex differences in GBM, we used a murine model of GBM with inactivation of Neurofibromin 1 and p53 function. This model has previously yielded important insights into sexual dimorphism in GBM. We performed a metabolic screen of male and female murine GBM cells and were able to recapitulate the sex differences in metabolite abundance we had observed in GBM patient samples. Furthermore, we manipulated metabolic pathways through glutamine deprivation and a glutaminase inhibitor and found greater sensitivity to the inhibition of glutamine metabolism in male GBM cells. In addition, we investigated cellular processes that depend on glutamine and found significant sex differences in TCA cycle flux. A major mechanism by which metabolism is regulated is the PI3K/mTOR pathway. We found greater activation of PI3K/mTOR pathway mediators in male GBM cells upon treatment with EGF, insulin, or IGF-1. Furthermore, when we inhibited this pathway with targeted drugs, we found significant sex differences in sensitivity to pathway inhibition. Together, these data indicate that male glioblastoma are characterized by enhanced glutamine metabolism and that the mTOR pathway may be a sex-specific regulator of glutamine metabolism in GBM. This dimorphism may contribute to sex differences in GBM incidence and outcome and suggests that sex has to be considered in metabolic targeting approaches.
Intra-Hippocampal Depletion of Microglia as a Tool to Examine the Role of Microglia in Learning Deficits Produced by Juvenile Immune Challenge
Mary Beth Bielicki1, and Jaclyn M. Schwarz, PhD1
1University of Delaware, Newark, DE, USA
Autism and ADHD are developmental disorders associated with learning deficits that have been linked to early-life immune activation. Of these disorders, males are more likely to be diagnosed than females. Microglia, the immune cells of the brain, are believed to play an important role in the development of hippocampal circuits during a critical juvenile period for learning. Clodronate is a cytotoxic drug that, when encapsulated in liposomes, is selectively ingested by and results in the death of phagocytic cells. This liposome-encapsulated clodronate (LEC) can be infused in the brain to selectively deplete microglia for 7 to 10 days. We have found that lipopolysaccharide (LPS) infection in rats on postnatal day (P) 21 produces hippocampal-dependent learning deficits on P24 in the Context Pre-exposure Facilitation Effect (CPFE) fear-conditioning paradigm. We are currently examining the role microglia play in this learning deficit by infusing LEC in the dorsal hippocampus to selectively deplete microglia in that region. Our goal was measure the time-course of microglial depletion to ensure that no microglia were present in the hippocampus during this critical learning period. Furthermore, we determined any differential effects LEC has on males versus females. We then measured cytokine expression produced by LPS during this timeline of microglial depletion. We will then examine whether depletion of microglia attenuates or enhances learning deficits in the CPFE paradigm following LPS infection. These experiments will elucidate any sex differences in how the absence of microglia during a juvenile immune challenge will influence development of hippocampal circuits that impact learning.
Anxiety Impacts Cognitive Decline in a Sex-Specific Manner in Alzheimer’s Disease
Mice Holly Hunsberger1, and Christine A. Denny1
1Columbia University, New York City, NY, USA
Neuropsychiatric disturbances, such as depression and anxiety, are observed in 90% of Alzheimer’s disease (AD) patients and are frequent in those at risk for AD. However, until recently, much of the research narrowly targeted comorbid depression. Clinical reports have provided evidence that anxiety symptoms predict the conversion to AD, over and beyond the effects of depression, memory loss, and even atrophy. Our preliminary evidence corroborates with clinical studies, showing that female AD (APP/PS1) mice exhibit anxiety-like behavior at 2 months of age as well as cognitive deficits in contextual fear conditioning (CFC) learning. In contrast, AD age-matched male mice do not exhibit depressive- or anxiety-like behaviors and do not develop contextual memory deficits until 6 months of age. To study how anatomical sex and anxiety impact AD progression, I used our activity-dependent tagging system, the ArcCreERT2 ×(ChR2)-EYFP × AD (APP/PS1) mice. These mice allow for brain-wide indelible labeling of neurons activated during learning, which then can be compared with secondary neuronal ensembles activated during memory retrieval. The neurons activated at both time points represent a memory trace or engram. Using the aforementioned transgenic design, we have reported impaired CFC memory and weakened memory traces in the dentate gyrus (DG) of male AD mice and have rescued memory loss by targeting DG neural ensembles. Here, we aimed to identify the neural ensembles linking anxiety and memory loss following AD progression. We found: (1) female AD mice exhibit anxiety-like behavior at an earlier age compared to controls and male mice, (2) in a contextual fear conditioning task, AD female mice show memory deficits as early as 2 months of age, (3) anxiety-like behavior correlated with memory impairment only in AD female mice, and 4) unlike their male counterparts, optogenetically stimulating encoding cells in the hippocampus did not rescue memory in female mice.
Females Have Enhanced Purinoceptor-Dependent Regulation of Sodium Excretion: Role for GPER
Eman Y. Gohar1, Malgorzata Kasztan1, Elizabeth M. Daugherty1, Shali Zhang1, Sarah H. Lindsey2, Edward W. Inscho1, and David M. Pollock1
1University of Alabama at Birmingham, Birmingham, AL, USA
2Tulane University, New Orleans, LA, USA
Hypertension is more prevalent in men compared to premenopausal women. This female advantage is lost when women reach menopause, suggesting protective roles for the female sex steroids, particularly estradiol (E2). Purinoceptor subtype Y2 (P2Y2) plays an important role in facilitating Na+ excretion. We recently reported that activation of P2Y2 in the renal medulla promotes Na+ excretion in male and ovariectomized (OVX) rats, but not in intact females. We hypothesize that intact females have higher renal medullary activity of P2Y2 in regulating Na+ excretion compared to male and OVX rats. We determined P2Y2 mRNA and protein expression and the effect of medullary purinoceptors (P2) inhibition on Na+ excretion in male, intact female, and OVX Sprague Dawley rats. P2Y2 mRNA expression was higher in the renal inner medulla from females compared to males (1.0 ± 0.1 vs 0.7 ± 0.1, P < .05). Phospholipase C (PLC-1δ) that mediates the downstream signaling for P2Y2 demonstrated a similar pattern. Interestingly, OVX eliminated these sex differences. Western blots performed using inner medullary lysates showed the same sex difference in P2Y2 expression. Renal medullary P2 receptor inhibition by suramin attenuated Na+ excretion only in intact females (0.4 ± 0.1 vs 0.9 ± 0.2 μmol/min, P < .05). E2 dose-dependently increased P2Y2 mRNA expression in cultured mouse inner medullary collecting duct cells. Given that G protein-coupled estrogen receptor (GPER) contributes to the nephroprotective effects of E2, we determined whether GPER ablation attenuates renal P2 expression. P2Y2 mRNA expression was lower in female GPER KO compared to wild-type female controls, but this difference was not observed in males. These data suggest that females have enhanced P2Y2-mediated regulation of Na+ excretion, compared to male and OVX animals, at least partially via an E2/GPER-dependent mechanism. This pathway may contribute to the enhanced ability of premenopausal females to handle dietary salt challenges.
Sex Differences in Microglia-Neural Signaling and Learning Following Early-Life Immune Activation in the Juvenile Rat
Brittany F. Osborne1, and Jaclyn M. Schwarz1
1University of Delaware, Newark, DE, USA
Dysregulation of the immune system during childhood leads to an increased risk for mental health disorders such as autism spectrum disorders, ADHD, and depression. Notably, these disorders exhibit a strong sex bias in their diagnosis. Microglia are the primary immune cells of the brain and are in constant communication with neurons, thus, activation of microglia can significantly influence the function of surrounding neurons. Microglia-neuron signaling is necessary for the proper formation of neural circuits which support the emergence and long-term maintenance of cognitive function. We found that immune activation with lipopolysaccharide (LPS; 100 µg/mL/kg) on postnatal day (P) 21 produces deficits in the emergence of hippocampal-dependent learning, days later, on P24 in male and female rats. We examined gene expression in the hippocampus at 2-, 4-, 8-, and 24-hours following immune activation and determined that there are sex differences in the inflammatory molecules IL-1β and IL-6. Additionally, males, but not females, have a persistent decrease in brain derived neurotrophic factor expression starting 4 hours post-LPS that persists until 24 hours. Finally, we found that males, but not females, have a significant increase in the expression of C3, an immune molecule that tags synapses for phagocytic elimination by microglia, 24 hours after LPS. Therefore, we next examined whether LPS on P21 alters microglia phagocytosis of synapses in the hippocampus differently between males and females and whether measures of neuronal morphology and spine density are altered on P24, when rats previously showed learning deficits. Our data suggest that sex-specific changes in microglia-neuron communication may underlie changes in neural circuit development in the hippocampus following immune activation with LPS. These changes may be a key mechanism underlying sex differences in vulnerability to developmental and neuropsychiatric disorders following early-life immune activation.
Investigating Gender Effects in Brain Structure and Composition Using Magnetic Resonance Imaging
Laagi Yoganathan1, Manpreet Sehmbi1, Benicio N. Frey1, and Nicholas A. Bock1
1McMaster University, Hamilton, Ontario, Canada
Magnetic resonance imaging (MRI) is widely used to study the structure and composition of the human brain. MRI-based volumetry has demonstrated gender effects in brain volume, with males typically having larger brain regions. In this study, we ask if gender differences extend to brain composition by estimating the myelin content of tissue using MRI. We use T1-weighted (T1W) MRI signal intensity as a surrogate measure of myelin in brain regions. We model total grey matter (GM) and total white matter (WM) volumes as well as average GM and WM signal intensities as a function of gender and age across adult development. We collected MRI data of 49 men and 63 women aged 17 to 45 years (men: M = 33, SD = 8; women: M = 29, SD = 8). We imaged at 3 different sites that had the same scanner and used identical MRI protocols. We used linear modelling to test for effects of gender and age on measures of volume and the T1W signal, while adding site as a confound variable. We fit the equation: Measure = Site + Age + Gender + Age × Gender to our data and calculated Cohen d for gender differences in volume and signal. We found that the effect of gender was stronger in GM volume (d = 0.896) and WM volume (d = 0.767) compared to GM signal (d = 0.273) and WM signal (d = 0.191). This suggests that volumes differ more than myelin content between genders and it is likely that myelin is not driving the volume difference. In future studies, we will investigate if myelin and volume deficiencies in the brain seen in major depressive disorder show an interaction effect between diagnosis and gender.
Impact of Sex Hormone-Binding Globulin (SHBG) on the Human Phenome: A Scan of Over 21 000 Traits in ∼300 000 Participants of UK Biobank
Ryan Arathimos1, Louise A. C. Millard1, Joshua A. Bell1, Caroline L. Relton1, and Matthew Suderman1
1Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
Sex hormone-binding globulin (SHBG) levels are highly heritable and have been previously linked to various traits and diseases, however, a systematic study of the effects of SHBG across the human phenome has not been attempted and may uncover novel associations. We aimed to use a hypothesis-free approach to systematically appraise the potentially causal associations of SHBG. We calculated a weighted genetic score of 9 SHBG-increasing alleles to proxy SHBG levels (as the exposure) and systematically tested its association with over 21 000 outcome phenotypes in participants of UK Biobank (N = 334 977), using a rule-based algorithm. This approach termed a Mendelian randomization phenome-wide association study (MR-pheWAS) exploits the approximate randomization of germline genetic variants at conception to overcome issues of confounding and reverse causation that are inherent to observational studies. We followed-up our top findings using more formal 2-sample MR analyses to evaluate whether estimates may be biased due to horizontal pleiotropy (where the exposure affects the outcome through a path other than through SHBG). We identified 8 outcome phenotypes associated with genetically-elevated SHBG in the MR-pheWAS after correcting for multiple testing. Follow-up of these phenotypes using 2-sample MR indicated associations of genetically-elevated SHBG with higher impedance of the right and left arms, lower pulse rate, higher odds of hip replacement, lower odds of cholesterol medication use in males and higher odds of gallbladder removal. Our results suggest that SHBG impacts several traits and diseases which should be prioritised for future investigations of the molecular effects of SHBG and to develop targets for therapeutic intervention. Our study highlights the emerging utility of big data approaches, such as MR-pheWAS, in health sciences for uncovering novel associations of exposures with disease.
Maternal Separation Leads to Sex-Specific Alterations in the Formation of Perineuronal Nets Around Parvalbumin-Expressing Interneurons in the Developing Rat Prefrontal Cortex and Basolateral Amygdala
Kelsea R. Gildawie1, Jennifer A. Honeycutt1, and Heather C. Brenhouse1
1Developmental Neuropsychobiology Lab, Psychology Department, Northeastern University, Boston, MA, USA
Early life experiences play a vital role in ensuring healthy brain development. Adverse experiences have a lasting impact on the prefrontal cortex (PFC) and basolateral amygdala (BLA), brain regions associated with emotion regulation. Early life adversity via maternal separation (MS) has sex-specific effects on expression of parvalbumin (PV), which is expressed in fast spiking GABAergic interneurons that are preferentially enwrapped by perineuronal nets (PNNs). Importantly, PNN formation coincides with the closure of developmental critical periods, regulating the activity of PV-expressing interneurons. Since aberrant PNN organization has been reported following adverse experiences in adolescence and adulthood, here, we investigated the impact of adversity early in life in the form of MS on the developing brain. Rat pups were separated from their dams for 4 hours per day from postnatal day (P) 2-20. Brains were perfused, cryoprotected, and sliced to 40 µm slices at juvenility (P20), adolescence (P40), and early adulthood (P70). Tissue sections containing the PFC and BLA were stained for Wisteria floribunda agglutinin (WFA) and anti-PV antibody to visualize WFA+ PNNs and PV-expressing interneurons, respectively. Z-stacks were obtained using fluorescent microscopy in 4 serial sections of the PFC and BLA. ImageJ was used to count WFA+ PNNs, PV cells, and PNNs surrounding PV cells, and density was calculated. Results demonstrate that PNN formation around PV-expressing interneurons is delayed in the PFC of females exposed to MS. Notably, this effect is not observed in PNNs surrounding non-PV cells. These data, however, do not demonstrate a sex-specific delay in PNN formation in the BLA following MS. Our findings indicate sex-and region-specific effects of MS on aberrant PNN formation around PV-expressing interneurons, implicating neuroplastic alterations following early life adversity that may be associated with sex differences in psychopathology and resilience.
Influence of Sex on Subjective and Objective Measures of Sleep and Biological Rhythms in Bipolar and Major Depressive Disorder
Anastasiya Slyepchenko1,2, Olivia R. Allega3, Xiamin Leng4, Luciano Minuzzi1,2,5, Maha M. Eltayebani2,5,6, Matthew Skelly7, Roberto B. Sassi5, Claudio N. Soares8,9, Sidney H. Kennedy9,10, and Benicio N. Frey1,2,5
1Neuroscience Graduate Program, McMaster University, Hamilton, Ontario, Canada
2Women’s Health Concerns Clinic, St. Joseph’s Healthcare, Hamilton, Ontario, Canada
3DeGroote School of Business, McMaster University, Hamilton, Ontario, Canada
4Brown University, Providence, RI, USA
5Mood Disorders Program, Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, Ontario, Canada
6Faculty of Medicine, Neuropsychiatry Department, Alexandria University, Alexandria, Egypt
7Department of Health Sciences, McMaster University, Hamilton, Ontario, Canada
8Queen’s University School of Medicine, Kingston, Ontario, Canada
9St. Michael’s Hospital, University of Toronto, Toronto, Ontario, Canada
10University Health Network, Toronto, Ontario, Canada
A New Role for Cortical Astroglial Cells in Sexual Differentiation of the Cerebral Cortex
G. M. Rurak1, A. Van Geel1, G. Coppola2, and N. Salmaso1,2
1Department of Neuroscience, Carleton University, Ottawa, Ontario, Canada
2Child Study Center, Yale University, New Haven, CT, USA
The study of sexual differentiation of the cerebral cortex has largely focused on neurons. However, astroglial cells play functional roles at all stages of cortical development; including forming synapses and neural networks. Although astroglial cells express estrogen, progesterone and androgen receptors, their role in cortical sexual differentiation has largely been ignored. In this study, we characterised cortical astroglial cells in male and female mice from postnatal day (P) one to adulthood. To achieve this, we employed a multimodel approach. Using a transgenic mouse line expressing GFP bound to a ribosomal protein under the pan-astroglial promoter Aldh1l1, we quantified the total number of astroglial cells, the expression of astroglial-associated cytoskeletal proteins, and morphological subtypes. We also used translating ribosome affinity purification in conjunction with RNASeq to phenotype the translatome of cortical astroglial cells at P1, P4, P7, P14, P35, and in adults. We found (1) significant developmental changes with respect to the number and phenotype of astroglial cells and (2) sex differences in the number of astroglia showing stem cell potential both in the early postnatal period and in adulthood. Surprisingly, whole astroglial translatome analysis showed few basal sex differences in cortical astroglia across all stages of development; however, we observed a robust sex difference in the astroglial-specific translatome at P1. Interestingly, many of the differentially expressed genes were associated with synapse and network formation. Because P1 is critical for sexual differentiation of the male brain, we hypothesized that direct stimulation of astroglia by estrogen might induce sex-specific cortical network development; we validated this hypothesis by using an aromatase inhibitor in neonatal males to block sexual differentiation. Together, our data suggest a potential new role for astroglial cells as key regulators of cortical sexual differentiation.
A Novel Role for DNA Hydroxymethylation in Sexual Differentiation of the Mouse Brain
Carla D. Cisternas1, Laura R. Cortes1, and Nancy G. Forger1
1Neuroscience Institute, Georgia State University, Atlanta, GA, USA
Many sex differences in the brain are differences in neuronal phenotype (ie, number of cells expressing a specific neurochemical marker). Epigenetic modifications, such as DNA methylation, control the development of cell phenotype throughout the body during embryogenesis, and sex differences in neurochemical cell phenotype could be due to differences in the control of DNA methylation. To test this, we first inhibited DNA methylation in the brains of newborn mice during the critical period of sexual differentiation. We found sex-specific effects (the inhibition of DNA methylation increased the number of calbindin-expressing cells only in females, and the number of estrogen receptor alpha cells only in males). As a result, sex differences were reduced or eliminated in the treated groups. We next hypothesized that DNA methylation during development depends on a balance between the addition of methyl groups (by DNA methyltransferases, DNMTs), and their removal (by 10-11 translocases, Tets). Tet enzymes convert 5-methylcytosine (5mC) to 5-hydroxymethylcytosine. This is a first step to removal of the methyl mark, but hydroxymethylation is also emerging as a stable epigenetic mark in its own right, especially in the brain where it is found at much higher levels than in other tissues. We find that both DNMTs and Tets are expressed at even higher levels in the neonatal brain than at later ages, and that sex differences in expression are found only during the first postnatal week. Males have greater expression of Tet2 and Tet3 and lower expression of Dnmt1 in the preoptic area of the hypothalamus and this is associated with less 5mC in the same region. We are currently examining the effects of a transient downregulation in Tet enzymes to test for a causal relationship between Tet enzyme expression and sex differences in neuronal phenotype. Overall, our results suggest the novel idea that DNA demethylation may primarily drive sex differences early in brain development.
The Race to Last Place: The Pace of Career Progression Among Women and Underrepresented Minorities
Allison Nunez1
1University at Albany, Albany, NY, USA
SUNY Recent NIH/NSF initiatives have focused on improving recruitment and retention of women and underrepresented groups in science in the face of obstacles for these groups. Prior work on biomedical researcher careers shows that both women and underrepresented minorities are less likely to attain last author positions (a proxy for peak researcher status) on publications and have not improved on this measure over 42 years (1967-2009). This paper uses a massive, population-level, longitudinal data set with rich author and publication information of over 1 million unique MEDLINE authors to address whether female and minority scientists are being “promoted” more slowly than comparable male and non-Hispanic white scientists. The paper also investigates if the speed to promotion depends on similarities between mentors and first-time authors; matched mentors may lead to better author outcomes through efficient communication channels but could impede productivity through reduced diversity. A competing risk model is fit for the relationship between gender/race/ethnicity and hazard, which describes the probability, at any given moment, of experiencing an event given that no event has happened yet. Two events are examined: first time last authorship attainment (LAA) and leaving the academic career prior to LAA. A higher hazard implies a shorter expected duration. The most basic model uses Cox Proportional Hazards with time invariant covariates. Preliminary results suggest that women experience a 21% lower LAA hazard (higher expected duration) than males, even within racial/ethnic subgroups (20.1%-24.9%), while also experiencing increased early exit hazard of about 13%, even within subgroups (7.2%-15.5%). When looking at LAA hazard, among female authors, those who are paired with a matched mentor on their first publication experience 15.1% greater LAA hazard than otherwise. As a whole, women’s expected LAA duration is longer than that of men, although matched mentors mitigate this.
Identification of Heterozygous Splice Site Variant in NR5A1 Gene Associated With 46, XY Gonadal Dysgenesis
Vasundhera Chauhan1, Rajesh Khadgawat1, and Viveka P. Jyotsna1
1All India Institute of Medical Sciences, New Delhi, India
XY gonadal dysgenesis (GD) is a rare form of differences of sex development (DSD) characterized by the underdeveloped gonads, which is due to sex chromosomal anomalies and/or mutations in genes associated with gonadal development. Almost 70% of patients with 46XY GD do not receive an accurate diagnosis due to unknown genetic aetiology. Here, we report the molecular analysis of 3 such cases using whole exome sequencing (WES) approach. Based on clinical and biochemical analysis, 3 patients were recruited from endocrine clinic with a presumptive diagnosis of 46, XY GD (2 with complete gonadal dysgenesis and 1 with testicular agenesis). Their exomes were captured using SureSelectXT Human All Exon V5 kit (Agilent technologies) sequenced on Illumina HiSeq2500 at 100× sequencing depth with 2 × 100 base-paired-end runs. Sequence reads (FASTQ files) were aligned to the human reference genome (hg19/GRch37 assembly). To minimize the risk of false-positive findings, only the high quality (Phred scores ≥ 30) novel and rare variants (minor allele frequencies <0.01 in 1000 genome, Exome aggregation consortium databases) were intersected with 18 known genes involved in gonadal development. Pathogenicity of the sequence variants was classified according to the American College of Medical Genetics and Genomics Standards and Guidelines. One novel heterozygous splice acceptor variant c.991-1G>A in NR5A1 gene in a patient diagnosed with complete gonadal dysgenesis. It was subsequently confirmed by Sanger sequencing using custom designed primers. This variant probably affects splicing by introducing a new intronic cryptic acceptor site for exon 6, as predicted by in silico analysis. NR5A1 gene is expressed in bipotential gonad and plays a critical role in gonadal sex determination and differentiation. Heterozygous point mutations in this gene are frequently reported in patients with dysgenetic gonads, however the mutations affecting splice site are rare.
Perinatal Androgens Drive the Development of Sex Differences in Mast Cell Phenotype and Anaphylaxis
Emily Mackey1,2 and Adam J. Moeser1
1Michigan State University, East Lansing, MI, USA
2North Carolina State University College of Veterinary Medicine, Raleigh, NC, USA
Highly prevalent and debilitating mast cell (MC)-associated immune disorders, including allergy/anaphylaxis, irritable bowel syndrome, and autoimmune disorders exhibit a female sex bias in both childhood and adulthood. Previously, we showed that female MCs exhibit an increased capacity to synthesis and store immune mediators and that adult female mice exhibited more severe IgE-mediated passive systemic anaphylaxis (PSA) characterized by greater serum MC histamine levels and hypothermia compared with males. Our recent data showed that sex differences in the MC and PSA severity were evident in prepubertal mice, suggesting a mechanism independent of adult sex hormones. Here, we investigated the role of perinatal androgens, a key early life component of sexual differentiation, in sex differences in MC phenotype and MC disease. Testosterone proprionate (100 μg sc qd) or vehicle was given to pregnant female mice E16-P0 and directly to pups PN1-7. IgE-mediated anaphylaxis was performed in gonadectomized control male (CM), control female (CF), and perinatally androgenized female (AF) offspring at 8 weeks of age. Serum histamine levels (CM: 768 ± 106, CF: 1406 ± 200, AF: 676 ± 110 ng/mL) and hypothermia responses (Δ temp: CM: −4.87°C ± 0.45°C, CF: −7.28°C ± 0.48°C, AF: −4.8°C ± 0.39°C) were ∼2× lower in AF than CF mice, while AF and CM mice had similar responses. Bone marrow MCs (BMMCs) derived from AF mice had lower histamine content (AF: 1305 ± 82 vs CF: 2082 ± 94 ng/106 cells) and 47% lower histamine release to IgE-Fc∊RI stimulus compared to CF BMMCs. MC-deficient KitWsh/Wsh mice engrafted with AF BMMCs had 48% lower serum histamine after anaphylaxis compared to KitWsh/Wsh mice with CF BMMCs. Together, these studies demonstrate that perinatal androgens masculinize the MC phenotype and reduce MC disease severity. These findings provide new insight into the mechanisms of sex differences in MC-associated immune disorders, which could lead to new therapeutic targets for MC diseases.
Sex Influences the Effect of Adiposity on the Arterial Stiffness and Renin-Angiotensin System Activity
C. Z. Kalenga1, S. Ramesh1, S. Dumanski1, J. M. MacRae1, K. Nerenberg1, A. Metcalfe1, D. Y. Sola1, and S. B. Ahmed1
1University of Calgary, Calgary, Alberta, Canada
Increased adiposity as a risk factor for cardiovascular disease is associated with increased renin-angiotensin system (RAS) activity; though whether this risk differs by sex is unknown. The objective is to evaluate the association between measures of adiposity (MoA) and arterial stiffness (AS) and RAS activity in women and men. It is hypothesized that the association between MoA and arterial RAS activity differs by sex. MoA (body mass index [BMI], waist circumference [WC], hip circumference [HC], waist to hip ratio [WHR], waist to height ratio [WHtR], fat mass% [FM%]) were measured in healthy participants in a fasting, high-salt state. Arterial stiffness (aortic augmentation index [AIx] and pulse wave velocity [PWV]) were measured at baseline and in response to angiotensin II (AngII) challenge, a validated marker of RAS activity. Associations were evaluated using linear regression analysis and stratified by sex. In females (n = 67, 37 ± 2 years, BMI: 25 ± 1 kg/m2), BMI, WC, WHR, and FM were associated with increased baseline AIx (AIx: BMI r = 0.33; WC r = 0.27; WHtR r = 0.35, and FM r = 0.25; P < .05). All MoA were positively associated with a blunted AIx response to AngII (BMI r = −0.30; WC r = −0.25; HC r = −0.31; WHR r = −0.13; WHtR r = −0.31, and FM r = −0.32; all values P < .001). No association was observed between any MoA and PWV. In males (n = 28, 39 ± 3 years, BMI 27 ± 1 kg/m2), only WHtR was associated with baseline AIx (r = 0.39; P = .04), though all MoA except HC were associated with PWV (BMI r = 0.32; WC r = 0.18; WHtR r = 0.34; FM r = 0.21; all values P < .05). BMI, WC, WHR, and WHtR were associated with a blunted AIx and PWV response to AngII (ΔAIx: BMI r = −0.37; WC r = −0.31; WHR r = −0.16; and WHtR r = −0.22; ΔPWV: BMI r = −0.39; WC r = −0.42; WHR r = −0.39; and WHtR r = −0.55; all values P < .05). In conclusion, sex-related differences in distribution of adiposity influence the association between anthropometric measures and AS and RAS activity, which may translate into sex-specific cardiovascular risk.
APOE genotype and Sex Influence Memory and the Hippocampus in a Mouse Model of Alzheimer’s Disease
Lisa R. Taxier1, Sarah M. Philippi1, Jason M. York2, Mary Jo LaDu2, and Karyn M. Frick1
1University of Wisconsin-Milwaukee, Milwaukee, WI, USA
2University of Illinois at Chicago, Chicago, IL, USA
The loss of circulating ovarian estrogens at menopause is correlated with increased risk of Alzheimer disease (AD) relative to men. Women carriers of the APOE4 genotype, which is the leading genetic risk factor for late-onset AD, are more likely than women of the APOE2 or APOE3 genotypes, and men of any APOE genotype to develop AD. Here, we hypothesized that APOE4-expressing female mice would exhibit impaired memory relative to APOE3-expressing females and males of any genotype. Six-month-old gonadally intact male and female mice expressing 5 familial AD mutations (5xFAD-Tg) and human APOE3 (E3FAD) or APOE4 (E4FAD) were trained on object recognition (OR) and object placement (OP) tasks to test object and spatial memory formation. Two weeks after the conclusion of testing, mice were trained with novel objects, and brains were removed and hemisected 5 minutes later. The dorsal hippocampus was dissected from one hemisphere for Western blot analysis of proteins including PSD-95, synaptophysin, and estrogen receptor alpha (ERα). The other hemisphere was Golgi impregnated for analysis of CA1 dendritic spine density. Male E3FAD mice exhibited intact OR and OP memory, whereas E3FAD females and E4FADs of either sex did not, suggesting preserved memory function in E3FAD males relative to females, and impaired memory in E4FAD mice of both sexes. Preliminary data indicate that levels of PSD95 were reduced in E4FADs compared to E3FADs, and levels of synaptophysin were lower in E4FAD females than every other group. Conversely, ERα levels were lower in E3FADs relative to E4FADs and in E3FAD males compared to E3FAD females. Spine analysis is ongoing. These data suggest that APOE4 genotype is associated with impaired object recognition and spatial memory, and that alterations in synaptic proteins and ERα may play a role. The results also suggest sex differences among APOE3 carriers that could provide insights into neurobiological mechanisms underlying sex differences in AD risk.
Pharmacogenomics Call for Sex-Sensitive Drug Safety and Effectiveness Policy Reform
Anna Levinsson1,2,3, Simon de Denus1,2,4, and Marie-Pierre Dubé1,2,4
1Beaulieu-Saucier Université de Montréal Pharmacogenomics Centre, Montreal, Quebec, Canada
2Montreal Heart Institute, Montreal, Quebec, Canada
3Faculty of Medicine, Université de Montréal, Montreal, Quebec, Canada
4Faculty of Pharmacy, Université de Montréal, Montreal, Quebec, Canada
Women have more adverse events related to cardiovascular drugs, including anti-hypertensive drugs, than men. Angiotensin II receptor blockers (ARBs) are a class of hypertension drugs acting on the renin-angiotensin system, specifically the angiotensin receptor 1, lowering the blood pressure. The angiotensin receptor 1 is encoded by the gene AGTR1. There are currently no antihypertensive treatment guidelines adapted specifically for women, despite that for several ARBs, serum concentrations in women have been shown to be twice that in men. The lack of sex-specific guidelines is due to a lack of published sex-specific studies which would form the evidence base. As proof of concept, we explored potential sex-differences in the effects of AGTR1 genotypes on systolic and diastolic blood pressure (SBP and DBP). The UK Biobank has 413 232 individuals (54% women) with complete data for variables used here. Eighty-seven single nucleotide polymorphisms (SNPs) in and surrounding AGTR1 were extracted and tested for interaction effect with sex on SBP and DBP respectively, in models adjusted for self-reported blood pressure treatment, smoking, and age. Significant sex*SNP term indicates SNP effects differ between sexes. Several SNPs showed interaction effects with sex. Sex*s78222114 for both SBP (β = 0.468, P value = .036) and DBP (0.301, 0.019). Strongest identified interaction effect was sex*rs4547666 (0.513, 0.005). SNP-effects in a target gene for anti-hypertensive treatment vary with sex. This may translate to sex-differences in the effect of ARBs on hypertension. Currently there is no requirement for clinical trials to report sex-specific drug testing, even when drug is intended for use in both sexes. This is a significant gap in drug security regulations, especially for women who are often underrepresented in drug trials. An urgent review of policy governing the pharmaceutical research-to-market process is called for, and requirements for sex-specific drug testing need to be implemented.
Sex Differences in Metabolic Aging of the Brain in Humanized APOE-∊4 Knock-in Rats: Implications for Alzheimer’s Disease
Aarti Mishra1,2, Zisu Mao2, Yuan Shang2, Loi Do3, Adam S. Bernstein3, Fei Yin2, Theodore P. Trouard3, and Roberta D. Brinton2
1Titus Family Department of Clinical Pharmacy, University of Southern California, Los Angeles, CA, USA
2Center for Innovation in Brain Science, University of Arizona, Tucson, AZ, USA
3Department of Biomedical Engineering, University of Arizona, Tucson, AZ, USA
Women APOE-∊4 carriers are susceptible to accelerated aging and undergo faster rates of cognitive decline. Metabolic dysfunction precedes the symptomatic cognitive decline in Alzheimer disease (AD). We hypothesized that the sexual dimorphism in APOE-∊4 carriers would be evident in metabolic aging and in women, it would be susceptible to endocrine aging. To study this, we used humanized APOE-∊4 gene knock-in rat model and conducted a longitudinal study. APOE-∊4 and wildtype (WT), male and female rats, were assessed at 4 aging windows: 7 to 8 months (m), 9 to 10 m, 12 to 13 m, and 15 to 16 m. Reproductive cyclicity in female rats was assessed by vaginal lavages. During the longitudinal follow-up, we conducted 18FDG-microPET/CT (18-fludeoxyglucose micro Positron Emission Tomography/Computational Tomography) to measure brain glucose uptake. Hippocampal RNA-Seq and cortical metabolomic profiles were generated at end-of-study. Magnetic resonance imaging was conducted to assess regional brain volumes and myelin integrity. APOE-∊4 females had a significantly lower brain 18FDG uptake than APOE-∊4 males. The decline in glucose uptake in APOE-∊4 females worsened with the onset reproductive senescence. Quantitative brain volume assessment showed that white matter areas in the APOE-∊4 female brain trended to be bigger whereas grey matter areas trended to be smaller than APOE-∊4 males. White matter microstructural assessment showed that APOE-∊4 females had significantly lower fractional anisotropy than males, possibly indicating lower myelin integrity. Transcriptomic and metabolomic analyses support imaging findings, as gene expression for oxidative phosphorylation and mitochondrial genes was upregulated, and TCA metabolites were significantly higher in the males in comparison to females. This longitudinal study demonstrates that APOE-∊4 in combination with endocrine transition worsens the metabolic trajectory in females predisposing them to cognitive decline.
Sex Differences in Vitamin D Deficiency and/or Supplementation in Hypertensive Patients
John M. Sousou1, Katelyn A. Bruno, PhD1, and DeLisa Fairweather, PhD1
1Department of Cardiovascular Medicine, Mayo Clinic, Jacksonville, FL, USA
Hypertension, also known as high blood pressure, remains one of the leading causes of death worldwide, and one of the greatest health issues. Hypertension is characterized by a resting systolic blood pressure of 140 mm Hg and a diastolic blood pressure of 90 mm Hg, or higher. Notable factors that may lead to hypertension include high cholesterol levels, diabetes, obesity, high intakes of sodium and trans fats, the renin-angiotensin system (RAS), and physical inactivity. Vitamin D, a fat-soluble steroid hormone primarily known for its essential role in calcium homeostasis and bone metabolism, has also been linked to hypertension. Recent studies suggest that vitamin D deficiency is linked to the development of hypertension; however, few of these studies evaluate sex differences. Utilizing Mayo Clinic’s artificial intelligence i2b2 tool, it was discovered that of the 1 041 900 patients with primary hypertension at the Mayo Clinic, 205 303 patients have at least one vitamin D lab draw. Within this sample, 58% of these patients are female, 90% are White, and 94% are over 45 years of age. Patients with a deficiency in vitamin D, characterized by a level of 20 ng/mL or lower, make up 27% of patients; of those with a deficiency, 92% are over the age of 45. Additionally, 32 196 patients are taking vitamin D supplements, 69% of which are females and 96% are over the age of 45. While disparities in hypertension by race and demographics have been thoroughly examined, sex differences in the involvement of vitamin D in patients with primary hypertension have not been fully investigated. This project examines data on sex differences in hypertension from the large number of patients at Mayo Clinic and investigates the role of vitamin D deficiency and/or supplementation on hypertension according to sex and age in order gain a further understanding of the pathogenesis of disease.
Sex Differences in Chronic Pain Conditions: Hypermobile Ehlers Danlos Syndrome and Fibromyalgia
Katelyn A. Bruno, PhD1, Andrea C. Morales, MD1, Rinald Paloka1, John M. Sousou1, Jenil B. Patel, MD1, Shelby T. Watford1, Anna A. Mease, MPH1, Nicholas A. Courson2, Peter T. Dorsher, MD3, Todd D. Rozen, MD4, DeLisa Fairweather, PhD1, Edsel B. Bittencourt, PT2, Lynsey A. Seim, MD5
1Department of Cardiovascular Medicine, Mayo Clinic, FL, USA
2Department of Rehabilitation, Mayo Clinic, FL, USA
3Department of Physical Medicine and Rehabilitation, Mayo Clinic, FL, USA
4Department of Neurology, Mayo Clinic, FL, USA
5Department of General Internal Medicine, Mayo Clinic, FL, USA
Hypermobile spectrum disorder (HSD) and hypermobile Ehlers Danlos Syndrome (hEDS) are estimated to occur in 3.5% or 255 million people worldwide. Based on Mendelian genetics, the sex ratio of hEDS patients is expected to be 1:1, but in fact the disease affects females more than males. Fibromyalgia is a chronic pain illness estimated to occur in 2% of the population (9:1 women to men). Previous studies examining comorbidities associated with fibromyalgia found that hypermobile syndromes including hEDS occur frequently in fibromyalgia patients (4-25 × more often). In spite of the large number of patients with these conditions, the pathogenesis of disease remains largely unknown. Although many patients have these conditions, the cause of the conditions and how they relate to other conditions like migraines, depression, autoimmune diseases, and heart disease are unknown. We performed a retrospective study examining sex and age differences in around 8000 patients from the Mayo Clinic electronic medical record that were diagnosed with HSD, hEDS, and fibromyalgia, as well as control subjects with complex regional pain syndrome (CRPS; a chronic pain condition without hypermobility). We also examined the presence of 65 comorbidities based on ICD-9/10 codes such as chronic pain, depression, migraines, and postural orthostatic tachycardia syndrome and 30 markers such as BMI and sex hormone levels. We found that HSD, hEDS, and fibromyalgia occur more often in women with hEDS occurring more often in premenopausal women and fibromyalgia occurring more often in postmenopausal women. The average number and types of comorbidities vary for each disease. We found that women with hEDS have significantly more comorbidities than patients with HSD or fibromyalgia. We also found that sex differences in comorbidities such as migraines, for example, are more prevalent in premenopausal women with hEDS. Knowing common comorbidities affecting patients could lead to a better understanding of the pathogenesis of disease and suggest better treatment strategies for patients that have overlapping conditions. Our findings highlight the importance of studying sex and age differences in disease and provide insight on factors that may contribute to chronic pain in patients with these conditions.
Sex Differences and Sexual Hormones Involvement in Early Stage of Aortic Valve Stenosis
Maxime Hervault1, Mohamed Salah Annabi1, Marine Clisson1, Anne-Julie Boilard1, Maxime Perron1, Mylène Shen1, Nancy Côté1, and Marie-Annick Clavel1
1Quebec Heart and Lung Institute, Quebec, Canada
Calcified aortic valve disease (CAVD) is the most prevalent valvulopathy in high-income countries. Previous studies demonstrated sex-specific differences in CAVD in aortic valve lesion with women presenting more fibrosis and less calcification than men. Moreover, women’s valve interstitial cells (VICs) had a lower rate of apoptosis and were less prone to calcification than men’s VICs. We aimed to evaluate the impact of sex and sexual hormones on CAVD fibro-calcific processes. We randomized 134 male and 131 female LDLr-/-/ApoB100/100/IGF-II mice fed with a high fat/sucrose/cholesterol diet to 6 different treatment groups: intact males (IM), castrated males (CM), testosterone supplemented CM (TCM, 0.05 mg/d), intact females (IF), ovariectomized females (OF), and estradiol supplemented OF (EOF, 28 μg/d). Gonadectomy was performed at 8 weeks of age. Hemodynamic severity of CAVD was evaluated by peak aortic jet velocity (Vpeak) on Doppler-echocardiography at 36 weeks of age. Collagen analyses were performed with picrosirius red staining. Vpeak was significantly higher in IM when compared to CM and testosterone supplementation partially reversed the castration’s effect (IM = 143 cm·s− 1; CM = 112 cm·s− 1; TCM = 122 cm·s− 1; all P < .01). In females, oestrogens seemed to have less or no impact on Vpeak (IF = 117 cm·s− 1; OF = 107 cm·s− 1; EOF = 116 cm·s− 1; all P > .11). Histological analyses had shown that leaflets of IF and EOF presented a higher collagen proportion than leaflets of IM and TCM (IM vs IF: 13.8% vs 24.2%, P = .03; TCM vs EOF: 12.6% vs 21.0%, P = .03), but this difference disappeared in gonadectomized mice (CM vs OF: 21.2% vs 20.4%, P = .90). Our results confirm sex-related differences in CAVD pathophysiology. In addition, they suggest that testosterone and estrogen modulate aortic valve fibrosis. Gene expression analysis will be performed to understand molecular mechanisms associated with this hormonal modulation.
An IL-6 Receptor Antagonist Effectively Attenuates Postpartum Anhedonia in the Female Rat but Has No Effect on Anhedonia Precipitated by Sub Chronic Stress
Nicole A. Haas1, Julie Gomez1, and Jaclyn M. Schwarz1
1University of Delaware, Newark, DE, USA
The National Institute of Mental Health has identified postpartum depression as one of several types of depression that affects 10% to 15% of all mothers; however, the exact underlying mechanisms that precipitate postpartum depression are still unknown. Similar to the dramatic change in hormone levels that occurs during pregnancy, the peripheral immune system is also significantly altered throughout pregnancy to protect the developing semiallogenic fetus from being rejected by the maternal immune system. We recently determined that there is also a dramatic change in the central immune system during and just after pregnancy in female rats. Specifically, we observed depressive-like behaviors on the day of birth that was associated with increased IL-6 expression in the maternal brain on the day of birth. Thus, the current study sought to determine whether blocking the function of IL-6, by infusing an IL-6 receptor antibody specifically in the postpartum brain, may prevent the anhedonia observed following birth. For comparison, we also examined whether blocking the function of IL-6 in the brain could prevent the expression of anhedonia caused by a week of forced swim in female rats. Similar to our previous findings, we measured significant anhedonia in postpartum female rats and in female rats that had a week of sub chronic stress. Treatment with an IL-6 receptor antibody into the brain effectively attenuated depressive-like behavior immediately postpartum (P = .026 vs postpartum IgG control treatment), but interestingly had no effect on the anhedonia produced by subchronic stress (P = .790). Analysis of cytokine expression in the brain revealed that the IL-6 receptor antibody could effectively attenuate the expression of IL-6 (P = .026) and brain derived neurotrophic factor (P = .034) in the medial prefrontal cortex of postpartum females. In contrast, the antibody had no effect on IL-6, BDNF, or other IL-6 signaling molecules in the brain following sub chronic stress. These results suggest that the molecular mechanisms that underlie the onset of anhedonia after birth and subchronic stress may be distinct. Moreover, the successful attenuation of postpartum anhedonia following the infusion of an IL-6 receptor antibody suggests that this antibody, or other drugs that affect IL-6 signaling in the brain, may be important potential targets for the relief for the symptoms associated with postpartum depression that may not be fully alleviated by typical antidepressants.
Sex Differences in the Circumstances Leading to Falls: Evidence From Real-Life Falls Captured on Video in Long-Term Care
Yijian Yang1, Kimberley S. van Schooten2, Joanie Sims-Gould1, Heather A. McKay1, Fabio Feldman3, and Stephen N. Robinovitch4
1University of British Columbia, Vancouver, British Columbia, Canada
2University of New South Wales, Sydney, New South Wales, Australia
3Fraser Health Authority
4Simon Fraser University, Burnaby, British Columbia, Canada
Falls are a major health concern for older adults. Understanding sex differences in fall circumstances may guide the design of fall management plans specifically to men and women. In this prospective cohort study, we analyzed real-life falls captured on video to compare scenarios leading to falls between men and women in 2 long-term care (LTC) facilities. We hypothesized that circumstances of falls are associated with sex, age, and health status. Between 2008 and 2016, we video-captured 1738 falls experienced by 231 men and 298 women (mean age = 83 ± 9 years) in 2 LTC facilities in British Columbia, Canada. Each video was analyzed to determine the causes of imbalance and the activities at time of falling. Using generalized estimating equation models, we examined how fall circumstances associated with sex, age, and health status. We found that men were more likely than women to fall from loss of support with an external object (odds ratio 1.37; 95% confidence interval: 1.08-1.73) and less likely to fall from tripping (0.72; 0.54-0.96). Men were more likely to fall while seated (1.42; 1.07-1.87) or while rising (1.49; 1.111.99), and less likely to fall while walking (0.61; 0.50-0.75). After adjusting for age and health status, sex remained significantly associated with loss of support and walking. Furthermore, regardless of sex, falls from loss of support were more common among individuals who were less independent in activities of daily living (ADL), who used more medications, and who used diuretic. Individuals with independent ADL and intact cognition were more likely to fall while walking, but less likely to fall while seated or while rising. Our results elucidate differences between older men and women in the scenarios that lead to falls, to inform sex-specific fall prevention strategies in the LTC setting.
Contribution of X-Escapee Genes to Stroke Sensitivity in Aged Animals
Abdullah Al Mamun1, Romana Sharmeen1, Louise D. McCullough1, and Fudong Liu1
1Department of Neurology, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, USA
Sex Differences in Nicotine Versus Non-Nicotine Factors Affecting Acute Smoking Reinforcement and Reward
Kenneth A. Perkins1
1University of Pittsburgh, Pittsburgh, PA, USA
Potential sex differences in sensitivity to acute nicotine reinforcement attracted little research interest 2 decades ago, but the prevailing view was that women were more sensitive to nicotine than men, partly given women’s preference for low yield, or “light,” cigarette brands (That view overlooked the impact of marketing, and lack of awareness then that a brand’s “yield” did not correspond to its nicotine delivery). Our work in this area from the start proposed the opposite view, that women were less sensitive than men to reinforcing (self-administration) and rewarding (self-reported hedonic) effects of nicotine per se, but more sensitive to the non-nicotine stimuli accompanying smoking behavior. Critical to understanding these differences was disentangling these factors by separate manipulation and control of nicotine dosing and of the non-nicotine smoking factors, which had not been done. Results of studies controlling for these factors indicate that, in general, men are more sensitive than women to nicotine dose effects on acute self-administration (via tobacco cigarettes, nasal spray, or IV) and self-reported reward, as well as craving relief. By comparison, women are more sensitive than men to olfactory/taste smoke stimuli on smoking self-administration and reward. Clinical implications include perhaps explaining the better smoking cessation outcomes due to nicotine versus placebo patch in men relative to women, as the patch provides adequate nicotine dosing but no non-nicotine smoke stimuli. Other research addressing possible moderating influences on these sex differences will also be noted.
Neuroinflammation and Physiological Damage Manifest Differently in Male and Female Rats Following a High Fructose Diet
Molly M. Hyer1, Alix. Kloster1, Laurel Kovalchick1, Anum Adrees1, Charlie Salome-Sanchez1, Samya K. Dyer1, Thomas Taetzsch2, Jonathan Feaster2, Gregoria Valdez2, and Gretchen N. Neigh1
1Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA, USA
2Virginia Tech Carilion Research Institute, Virginia Tech, Roanoke, VA, USA
Fructose consumption in adolescents is accompanied by increased incidence of childhood diabetes, metabolic disorder, and obesity that can last into adulthood. Adult male rats that consumed a high-fructose diet (HFD) in adolescence have dysregulated emotional processing and upregulated gene expression of neuroinflammatory markers yet parallel changes in females are unknown. Furthermore, the impact of diet-induced neuroinflammation on structural and functional consequences is unexplored. The current study aimed to determine the extent to which a HFD altered neural structure and function and the inflammatory mechanisms responsible for these changes. Wister rats were fed either chow or a HFD (55% fructose) beginning on postnatal day (PND) 23 and for the duration of the study. On PND 80, rats were trained on the Barnes Maze task to assess cognition. Fructose-fed males, but not females, displayed impaired cognitive flexibility. Accompanying this deficit, fructose-fed males had more reactive microglia in the hippocampus. These findings suggest that in males, a HFD activates microglia which may contribute to functional deficits. Investigation of synaptic density and dendritic complexity is ongoing. Peripherally, fructose-fed females displayed aggressive liver pathology suggestive of nonalcoholic liver disease despite both sexes displaying elevated uric acid, a by-product of fructose metabolism and driver of fatty liver disease. Both sexes also displayed a motor impairment that was correlated with increased acetylcholine receptor fragmentation at the neuromuscular junction. Taken together, the results from this study suggest that a high-fructose diet consumed from adolescence into adulthood disproportionally impairs cognitive function and neuroinflammation in males while females appear largely protected from diet-induced neural deficits despite widespread peripheral alterations.
Inflammatory Response to Wood Smoke and Live Attenuated Influenza Virus Is Sex-Specific in the Human Airway
Meghan E. Rebuli1, Adam M. Speen1, Elizabeth M. Martin1, Kezia A. Addo1, Erica A. Pawlak1, Ellen Glista-Baker1, Carole Robinette1, Haibo Zhou1, Terry L. Noah1, and Ilona Jaspers1
1University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
Exposure to particulates from burning biomass is an increasing global health issue. Burning biomass, including wood smoke, is associated with increased lower respiratory infections. Therefore, our objective was to determine whether acute exposure to wood smoke modifies nasal inflammatory responses to influenza. Healthy young adults (N = 39) were randomized to a 2-hour controlled chamber exposure to wood smoke, where exposure levels were controlled to particulate number, (WSP) (500 μg/cm3), or filtered air (FA), followed by nasal inoculation with a vaccine dose of live attenuated influenza virus (LAIV). Nasal lavage was performed on pre-exposure (day 0) and days 1 and 2 postexposure. Nasal lavage fluid cells were analyzed for inflammatory gene expression profiles and cell-free fluid was assayed for cytokines. Only IP-10 protein levels were affected, suppressed, by WSP exposure in aggregate analysis. Subsequent analysis indicated an exposure*sex interaction, prompting additional analyses of WSP- and LAIV-induced changes in males and females. Inflammation-related gene expression profiles differed between the sexes, at baseline (males greater than females), after LAIV inoculation (females greater than males), and after WSP exposure (increase in males and decrease in females), demonstrating that WSP-and LAIV-induced changes in antiviral defense responses in the nasal mucosa occur in a sex-specific manner. Therefore, WSP exposure resulted in minimal modification of LAIV-induced responses in aggregate analysis. In contrast, analyzing WSP-induced modification of LAIV responses in the sexes separately unmasked sex-specific differences in response to exposure. These data highlight the need for additional studies to understand sex-specific pollutant-induced effects.
Sex-Specific Effects of Maternal Separation on Sonographic Structure and Acoustic Properties of Juvenile Rat Ultrasonic Vocalizations (USVs)
Lauren E. Granata1, Jennifer A. Honeycutt1, and Heather C. Brenhouse1
1Developmental Neuropsychobiology Lab, Psychology Department, Northeastern University, Boston, MA, USA
Adverse early life experiences compromise healthy development and can increase susceptibility to psychiatric disorders and social dysfunction later in life. Caregiver-infant interaction is critical for typical neural and social development. Rat ultrasonic vocalizations (USVs) are a communication tool that can also be interpreted as an indicator of affective state. While adult calls are classified into 2 categories (22 kHz and 55 kHz), pup vocalizations are highly variable in sonographic structure and acoustic properties. USVs have been shown to play a role in maternal-pup interaction and are induced by acute isolation in pups. Thus, pup USVs play a role in the frequency of maternal-pup interactions. From postnatal day (P)10 to P20, USVs increase in bandwidth, duration, and frequency, indicating the importance of this period to the development of adaptive acoustic properties. Given the role of USVs in mother-pup interactions and the changes they undergo during development, we assessed the impact of repeated maternal separation (MS) on USV properties in juveniles. Pups were separated from dams for 4 hours per day from P2-20. On P22, pups were isolated in a small cage with home cage bedding for the first 5 minutes of weaning while USVs were recorded. Spectrograms for each recording were created, and 9 unique sonographic structures were identified. Individual USVs were classified by type, and duration, peak frequency, and bandwidth were calculated in DeepSqueak. Results reveal that regardless of rearing condition, females emitted more fragmented and fewer inverted U-shaped calls than males. Both males and females exposed to MS emitted more complex calls and fewer upsweeps than controls, while MS decreased short calls only in females. These results demonstrate that male and female juveniles exhibit unique structural repertoires differentially affected by MS, which may provide insight into sex differences in the influence of early life adversity models on affective state.
Sex-Specific Regulation of the VTA GABA Neurons by Subchronic Stress
Chloé Bouarab1, Brittney Thompson1, Marissa Dimola1, and Abigail M. Polter1,2
1Department of Pharmacology and Physiology, George Washington School of Medicine and Health Sciences, Washington, DC, USA
2George Washington Institute for Neuroscience, Washington, DC, USA
Women are twice as likely as men to be diagnosed with a mood or anxiety disorder. Given that stress plays a significant role in the development of these diseases, sexual dimorphisms in the response to stress are likely to be a critical factor in the enhanced vulnerability of females. Males and females exhibit divergent responses to stress at all levels, from molecular signatures to behavioral adaptations. Subchronic variable stress (SCVS) is a behavioral paradigm in which female mice develop anhedonia and anxiety, but males do not (LaPlant et al, 2009; Hodes et al, 2015). In this study, we apply this model to investigate the role VTA GABA neurons play in the sexually dimorphic response to stress. Dysregulation of the mesolimbic reward circuitry is implicated in the pathophysiology of stress-related illnesses. The VTA acts as a critical node in the brain’s reward circuitry. VTA GABA neurons regulate activity of the mesolimbic dopaminergic pathway, modulate reward, and anxiety-related behaviors and are activated by acute stressors; however, little is known about neuroadaptations in these neurons in response to chronic or repeated stressors. We hypothesize that SCVS increases activity of VTA GABA neurons in female animals and that reversing this will decrease SCVS-induced behavioral deficits. In our study, we show that SCVS causes social and other behavioral deficits in females and that inhibition of VTA GABAergic neurons reverses some, but not all, of these deficits. In parallel, using whole-cell electrophysiology, we found that stress increases GABAergic tone in both males and females, but only females exhibit a decrease in the firing rate of dopaminergic neurons. This suggests that there may be an additional protective mechanism in males to maintain activity of the VTA. Our data show that regulation of the VTA microcircuitry in response to stress is sexually dimorphic and may play a role in the development of maladaptive behavioral responses.
A Single Exposure to Δ9-Tetrahydrocannabinol Reduces Cell Proliferation in the Dorsal Hippocampus and Nucleus Accumbens of Peripubertal Male, but Not Female, Rats
Travis E. Hodges1, Djavad Mowafaghian2, Bonnie Lee1, Djavad Mowafaghian2, Tristan J. Hynes1, Djavad Mowafaghian2, Mason M. Silveira1, Djavad Mowafaghian2, Graeme D. Betts1, Djavad Mowafaghian2, Sukhbir Kaur1, Djavad Mowafaghian2, Jacqueline-Marie N. Ferland3, Yasmin Hurd3, Catherine Orr4,5, Hugh Garavan5, Catharine A. Winstanley1, Djavad Mowafaghian2, Liisa A.M. Galea1, and Djavad Mowafaghian2
1University of British Columbia, Vancouver, British Columbia, Canada
2Centre for Brain Health
3ICAHN School of Medicine
4University of Vermont, Burlington, VT, USA
5Swinburne University of Technology, Melbourne, Australia
The endocannabinoid system undergoes functional changes during adolescence and regulates neural plasticity, such as cell birth, in the brain. Moreover, neural plasticity in brain regions such as the hippocampus and nucleus accumbens, both implicated in drug-seeking behaviour, is heightened during the adolescent period, which may, in turn, render these regions more susceptible to endocannabinoid exposure. Here, we tested the hypothesis that a single exposure to Δ9-Tetrahydrocannabinol (THC), an active ingredient in cannabis, would alter cell birth in the adolescent rat brain. In addition, we investigated whether the effects of THC would be sex-dependent and dependent on a specific stage of adolescence (early-, mid-, or late-adolescence). Separate cohorts of male and female rats were injected with THC or saline on either postnatal day (PND) 31 (early-adolescence), PND 43 (mid-adolescence), or PND 56 (late-adolescence). Brains were collected 24 hours after injection and Ki67, an endogenous marker of cell proliferation, was examined in the dorsal hippocampus and nucleus accumbens. Ki67 decreased from early- to late-adolescence in the hippocampus (P = .047) and nucleus accumbens (P = .009) in both males and females. PND 43 males injected with THC had reduced Ki67 in the hippocampus (P = .016) and in the nucleus accumbens (P = .039) compared with vehicle-injected males. No differences were found between THC-injected and vehicle-injected females or at any other age-group in the males or in females. These data suggest a sex-specific critical period during adolescence wherein cell proliferation is vulnerable to a brief exposure to THC only in males, the peripubertal period. Moreover, these findings indicate that even a single exposure to THC during the middle of adolescence affects cell proliferation in multiple regions implicated in the reward circuit. Whether these changes have lasting impacts on behaviour and neural plasticity will be important to explore in future studies.
Sex-Stratified Regulatory Gene Networks of Coronary Artery Disease Reveal Sex-Specific Key Drivers of Atherosclerotic Disease
Robin J. G. Hartman1, Simon Koplev2, Angela Ma2, Gerard Pasterkamp1,3, Johan L. M. Björkegren2,4,5, and Hester M. den Ruijter1
1Laboratory of Experimental Cardiology, University Medical Center Utrecht, Utrecht, the Netherlands
2Department of Genetics & Genomic Sciences, Institute of Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
3Laboratory of Clinical Chemistry and Haematology, UMC Utrecht, the Netherlands
4Integrated Cardio Metabolic Centre, Department of Medicine, Karolinska Institutet, Karolinska Universitetssjukhuset, Huddinge, Sweden
5Clinical Gene Networks AB, Stockholm, Sweden
The majority of coronary artery disease (CAD) research is performed on pooled data sets of both men and women, potentially masking effects important for either sex. To address this issue, we performed sex-stratified gene network analysis in STARNET, a multitissue genetics of RNA expression study of CAD patients undergoing a coronary artery bypass. As STARNET has sufficient patients to perform sex-stratified analyses (n = 538, 31% women), we first determined how network connectivity is affected by varying the proportion of sex (equally powered using 160 men and 160 women) within the sample population. A network obtained from expression data derived from 70% males or females looks similar to networks obtained from males or females alone (100%). Strikingly, however, networks obtained from 50% females and 50% males do neither reflect male nor female CAD biology. Hence, we generated sex-specific regulatory gene networks (RGNs) from RNA sequence data of the atherosclerotic aortic arterial wall. Network modules were annotated and ranked with sex-specific expression quantitative trait loci, clinical data, and gene ontologies. Relevant male modules were mostly enriched for immune response terms and inflammatory processes. Interestingly, the relevant female modules mostly lacked any notable enrichment, as proper gene symbols were lacking (46%-69% missing gene symbols for ♀ modules, 7%-9% for ♂ modules), and thusly research on these genes is lacking as well. Bayesian network analyses of the top-ranked network modules revealed sex-specific key network drivers in CAD (263 in women and 150 in men, and 64 overlapping). Our findings underline the importance of sex stratification in clinical studies with high-dimensional omic data, and underscore the lack of knowledge on female CAD. Sex-specific genomic studies are therefore a natural first step toward personalized medicine of CAD.
Sex Differences in Autosomal DNA Methylation of Atherosclerotic Plaques From Patients Undergoing Carotid Endarterectomy
Robin J. G. Hartman1, Marten A. Siemelink1,2, Saskia Haitjema3, Koen F. Dekkers4, Arjan Boltjes3, Michal Mokry1,3,5, Gert Jan de Borst6, Bas T. Heijmans4, Folkert W. Asselbergs7, Gerard Pasterkamp1, Johan L. M. Björkegren8,9,10,11, Sander W. van der Laan3, and Hester M. den Ruijter1
1Laboratory of Experimental Cardiology, University Medical Center Utrecht, Utrecht, the Netherlands
2Department of Clinical Genetics, University Medical Center Utrecht, Utrecht, the Netherlands
3Laboratory of Clinical Chemistry and Haematology, University Medical Center Utrecht, Utrecht, the Netherlands
4Molecular Epidemiology, Department of Biomedical Data Sciences, Leiden University Medical Center, Leiden, The Netherlands
5Laboratory of Pediatric Gastroenterology, Wilhelmina Children’s Hospital, University Medical Center Utrecht, Utrecht, the Netherlands
6Department of Vascular Surgery, University Medical Center Utrecht, Utrecht, the Netherlands
7Department of Cardiology, University Medical Center Utrecht, Utrecht, the Netherlands
8Department of Genetics & Genomic Sciences, Institute of Genomics and Multiscale Biology
9Icahn School of Medicine at Mount Sinai, New York, New York, USA
10Integrated Cardio Metabolic Centre, Department of Medicine, Karolinska Institutet, Karolinska Universitetssjukhuset, Huddinge, Sweden
11Clinical Gene Networks AB, Stockholm, Sweden
Sex differences are evident in atherosclerosis with women having more stable plaques and plaque erosion as substrate for cardiovascular disease, as compared to men where plaque rupture is dominant. The extent to which these differences are correlated to DNA methylation (DNAm) in atherosclerotic plaques is not known. To assess sexual dimorphic autosomal DNAm at CpG-dinucleotides (CpGs) in atherosclerotic plaques from carotid endarterectomy patients, we performed an epigenome-wide association study on sex (♀ n = 180, ♂ n = 495). We applied a Bayesian method to control for latent bias and inflation. In all, 2464 CpG sites were differentially methylated between the sexes. As DNAm is heavily cell-type and tissue-specific, we determined how much of the found sex differences in DNAm are driven by plaque composition. The strongest effects on DNAm sex differences were observed for smooth muscle cell content and intraplaque hemorrhage, affecting 1336 (54.2%) and 1358 (55.1%) of the total number of differentially methylated CpGs, respectively. The majority of CpGs (80.6%) not affected by plaque composition are methylated more in females and more often located in promoters than those in males, which are more often located in gene bodies. In addition, we associated genetic data with DNAm in carotid plaques in both sexes, showing that 70.4% of differentially methylated CpGs can be affected by sex-specific genetic variation. Additional RNA-sequencing data of atherosclerotic aortic root from the STARNET study (160 ♀ vs 160 age-matched ♂) showed that genes with more promoter methylation in women have lower expression in women as well (χ2 test P value = .003). In conclusion, substantial sexual dimorphic autosomal DNAm exists in atherosclerotic plaques, partly explained by plaque composition and genetic variation. These data provide insight into the etiological differences between the sexes in atherosclerosis which may be linked to differences in DNA methylation.
Sex Differences in Cognitive Performance in Aging Common Marmoset Monkeys (Callithrix jacchus)
Emily S. Rothwell1 and Agnès Lacreuse1
1University of Massachusetts, Amherst, MA, USA
Evidence of sex differences in trajectories of age-related cognitive decline is mixed in the literature such that some studies find no sex differences whereas others point to steeper decline in men than women in many cognitive domains. The goal of this study was to evaluate sex differences in cognitive aging in a nonhuman primate model. Common marmosets (Callithrix jacchus) are excellent models to study cognitive aging because they have a short life span, sophisticated cognitive abilities, and patterns of brain aging that resemble those of humans. We studied cognitive function in male and female marmosets longitudinally over 3 years. At the beginning of the study, marmosets were considered middle-aged (mean age ∼ 5 years; n = 13 males, 14 females) and in the final year were considered old-aged (mean age ∼ 8 years; n = 8 males, 6 females). Monkeys were tested each year on a reversal learning task with 3 pairs of stimuli using a touchscreen computer. We quantified cognitive performance as the number of trials to reach a 90% correct criterion on simple discrimination (SD) and simple reversal (SR). SD and SR performances were averaged across the 3 pairs of stimuli presented each year. Cognitive performance improved from year 1 to year 2 as a result of practice effects, but did not change from year 2 to year 3. While there was no sex difference in SD performance across the 3 years, sex differences were apparent in SR performance in years 1 and 2. Specifically, males took fewer trials to reach criterion in SR tasks compared to females at year 1 and year 2. This sex difference was not apparent at year 3, which may suggest that sex differences in cognitive performance diminish with age.
Sex Differences in Clinical Features, Comorbidities and Treatment of Primary Headache Syndromes
Gary R. Salomon1, Katelyn A. Bruno, PhD1, Todd D. Rozen, MD2, Edsel B. Bittencout, PT2, John Leschitz, DPT2, and DeLisa Fairweather, PhD1
1Department of Cardiovascular Medicine, Mayo Clinic, FL, USA
2Department of Physical Rehabilitation, Mayo Clinic, FL, USA
Primary headache syndromes encompass a heterogeneous group of neurologic disorders that cause recurrent or persistent head pain without any clear underlying cause. Sex differences in risk and clinical presentation vary across headache disorders. Migraine is 3× more prevalent in women than men, and women report longer headache duration, greater disability, increased risk of recurrence, and a longer recovery time. In contrast, the overall male to female ratio for cluster headache is 6:1 with a similar clinical presentation in both men and women. Several hypotheses have been proposed to explain these differences, including fluctuations in sex hormones, genetic factors, differences in exposure to environmental stressors, as well as differences in response to stress and pain perception; but it remains unclear whether these findings extend to other primary headache syndromes. In this study, we investigated sex differences in the clinical features, comorbidities, and treatment of the most common primary headaches including migraine, chronic migraine, new daily persistent headache, and cluster headache. This retrospective study utilized the Mayo Clinic electronic medical record to examine demographics, concomitant medical conditions, vitals, biomarkers, and treatment responses in patients diagnosed with a primary headache according to ICD-9/10 codes. In an initial analysis, we accessed 4826 patients (3749 females/1077 males) diagnosed with a primary headache syndrome at Mayo Clinic Florida. We found that 1584 (33%) out of 4826 headache patients have migraine or chronic migraine and of those 85% are women. One treatment to reduce pain in migraine patients is manual physical therapy, and so we examined the percentage of migraine patients receiving physical therapy for their migraine. Of migraine patients, 24% were seen by the Headache Clinic physical therapist for treatment, with 25% of women versus 20% of men seeing a physical therapist. Results from this study will expand our understanding of the mechanisms underlying sex differences in headache syndromes, and how sex differences impact therapeutic treatment choices.
Identifying Sex Differences in the Molecular Mechanisms of Socially-Mediated Pubertal Suppression
Mariela Faykoo-Martinez1, Dustin J. Sokolowski1, Zaichao Zhang2, Kyoko E. Yuki2, Troy Collins1, Mark R. Palmert2, Michael D. Wilson2, and Melissa M. Holmes1
1University of Toronto, Toronto, Ontario, Canada
2Hospital for Sick Children
Pubertal timing is highly heritable and directly influenced by a myriad of environmental conditions including psychosocial stressors. Importantly, the timing of puberty, its susceptibility to social modulation, and associated health outcomes, all differ between males and females. Thus, understanding sex-specific and sex-similar mechanisms controlling pubertal timing has tremendous importance for human health. The naked mole-rat (NMR) is a unique rodent exhibiting extreme socially-mediated reproductive suppression. NMRs reside in large colonies of adults who remain in a prepubertal state due to the presence of a single, dominant breeding pair. Strikingly, most NMRs will never go through puberty unless they are removed from the suppressive cues of their colony. It is not known how puberty is suppressed in adult male and female NMRs, though sex differences in mechanism likely exist (eg, male subordinates show reduced suppression compared to females). To discover molecular mechanisms contributing to socially-mediated reproductive suppression, we are comparing gene expression and epigenetic profiles in candidate tissues obtained from males and females within the colony (breeding pairs and subordinates) to sex-matched animals that have been removed from their colony for 1 or 4 weeks, which triggers pubertal onset (early and late social/reproductive transitions). Using RNA-seq, we are profiling 6 reproductively and socially relevant regions of the brain as well as the pituitary and gonads. We have identified gene modules in the dorsal hypothalamus (stress inputs) and ventral hypothalamus (control of pubertal timing) that differ by social/reproductive status and sex. Overall, we find a larger number of changes in the female gene expression profile across the transition. For example, genes involved in dopaminergic pathways are higher in subordinate and breeder animals relative to females removed from colony-living. Gene expression profiling in other regions is currently underway.
Adolescent Stress Reprograms Sex Differences in the Medial Amygdala Transcriptome and Reward in Mice
Deena M. Walker1, Xianxiao Zhou2, Ashley M. Cunningham1, Casey K. Lardner1, Catherine J. Peña1, Hannah M. Cates1, Arthur Godino, Andrew P. Lipschultz, Orna Issler, Yentyl Van Der Zee, Caleb J. Brown, Marine Salery, Michael E. Cahill, Erin S. Calipari, Rose C. Bagot1, Georgia E. Hodes1, Marie A. Doyle, Efrain Ribeiro1, Scott J. Russo1, Andrew Wolfe3,4, Pamela J. Kennedy5, Bin Zhang2, and Eric J. Nestler1
1Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
2Department of Genetics and Genomics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
3Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, MD, USA
4Department of Physiology, Johns Hopkins School of Medicine, Baltimore, MD, USA
5Department of Psychology, The University of California Los Angeles, Los Angeles, CA, USA
Adolescence, a time of heightened sensitivity to rewarding stimuli, is associated with vulnerability to psychiatric disorders. Social isolation stress (SI) during adolescence, but not adulthood, causes permanent changes in reward-associated behaviors in males. However, little is known regarding how females respond to adolescent SI. Our preliminary data suggest that adolescent SI reverses sex differences in reward behaviors and permanently reduces baseline sex differences (M > F) in neuronal projections from meAMY to ventral tegmental area (VTA). Given these circuit-specific and behavioral alterations, we tested the hypothesis that SI alters the meAMY transcriptome in a persistent and sex-specific manner, resulting in long-term changes in sexually dimorphic behaviors. Mice were isolated or group housed (GH) from postnatal day P22 to P42, then GH until ∼P90. Transcriptome-wide changes in meAMY were investigated by RNA-seq after cocaine (acute/chronic) or saline. Gene coexpression network analysis was conducted and key drivers of sexually dimorphic gene expression were identified. To determine if manipulation of a key driver gene could recapitulate the effects of SI, a gene of interest was virally overexpressed in the adult meAMY using AAV2. Sexually dimorphic genes were disproportionately affected by SI. Gene coexpression analysis revealed that SI results in the loss of sexually dimorphic gene coexpression in the meAMY and identified key drivers of sex-specific patterns of expression. Overexpression of Crym, a key driver, in the adult meAMY induced sex-specific effects on baseline sexually dimorphic and reward-associated behaviors. These data suggest that the meAMY plays an important role in sex differences in cocaine reward and that SI disrupts sex-specific adolescent development. Overexpression of Crym in the adult meAMY not only recapitulates the effects of SI but induces sex-specific behavioral plasticity in adult animals.
Estimation of Chromatin State and Transcription Factor Dynamics Across Sex, Estrus Cycle, and Puberty in the Mouse Hypothalamus
Dustin J. Sokolowski1, Huayun Hou1, Liis Uuskula-Reimand1, Mariela Faykoo Martinez1, Cadia Chan1, Anna Roy1, Anna Goldenberg1, Mark R. Palmert1, and Michael D. Wilson1
1University of Toronto, Toronto, Ontario, Canada
Puberty is a crucial developmental period marked by sexual maturation and the production of gametes through activation of the hypothalamic–pituitary–gonadal axis. The timing of pubertal onset varies across sex and ethnicity; these variations have been associated with sex-specific health complications in later life. Yet, despite its importance, the mechanisms underlying pubertal onset are not well understood. Pubertal onset coincides with large changes in gene expression controlled by alterations in transcription factor (TF) activity. To investigate mechanisms of pubertal onset, we measured hypothalamus gene expression (RNA-seq) and epigenetic markers (ChIP-seq: H3K4me2, H3K27me3, H3K27ac, and H3K36me3) before/after puberty in mice of both sexes and at both stages of estrus cycle in postpubertal females only. We integrated epigenetic data from the 4 histone posttranslational modifications to create a chromatin state map of the mouse hypothalamus. We then identified regions with a change in chromatin state and nucleosome repositioning across puberty and sex before completing TF motif enrichment. We found that 11 transcription factors are significantly enriched for genes with repositioned nucleosomes and alterations in chromatins states when comparing across sex, including Egr1, and Esra which also have a plausible role in puberty. We are currently testing Egr1 and Esra to investigate their combined role in sex-differentiation and puberty using ChIP-seq.
Women With Sjögren’s Syndrome and Low Vitamin D Levels Are at Increased Risk for Cardiac and Autoimmune Diseases and Chronic Pain
Jenil Patel, MD1, Katelyn A. Bruno, PhD1, Carolina Morales-Lara, MD1, John M. Sousou1, Gary Salomon1, Rinald Paloka1, Peter T. Dorsher, MD2, Todd D. Rozen, MD3, Edsel B. Bittencourt4, Paldeep S. Atwal, MBChB5, Lynsey A. Seim, MD6, and DeLisa Fairweather, PhD1
1Department of Cardiovascular Medicine, Mayo Clinic, FL, USA
2Department of Physical Medicine and Rehabilitation, Mayo Clinic, FL, USA
3Department of Neurology, Mayo Clinic, FL, USA
4Department of Rehabilitation Services, Mayo Clinic, FL, USA
5Atwal Clinic, FL, USA
6Department of Internal Medicine, Mayo Clinic, FL, USA
Autoimmune disease (AD) affects nearly 50 million Americans and around 80% of those affected are women. Sjögren’s syndrome (SS) is a chronic, multisystem AD characterized by inflammation of lacrimal and salivary glands, resulting in dryness of the eyes and mouth. The prevalence of SS is greatly skewed toward women compared to men with an overall sex ratio of 16:1. An estimated 1 billion people worldwide have deficient or insufficient/low levels of vitamin D (VitD). Considerable evidence indicates that low VitD is associated with an increased risk of autoimmune and cardiovascular disease (CVD), yet it remains unclear whether low VitD is simply a biomarker or has a true pathologic role. We hypothesize that women with Sjögren’s syndrome and low VitD (< 20 ng/mL) are at increased risk of cardiac and autoimmune comorbidities compared to men with SS. We included patients diagnosed with SS in the Mayo Clinic electronic medical record (EMR) by ICD-9/10 codes. Autoimmune and cardiovascular comorbidities and biomarker levels were then extracted from the EMR to analyze for risk by sex and VitD using 20 ng/mL as a cutoff for low VitD. From a total of 13 852 patients with SS, we identified 5897 patients (5258 women/ 639 men) who had SS and a VitD lab value. Out of these, 17% were women and 19% men with low VitD. Women with low VitD levels had more ANA (P = .001), SSA/Ro (P = .004), and SSB/La (P = .02) autoantibodies compared to women with sufficient VitD, but no significant differences were found in men. We found that women with SS and low VitD had a higher risk of congestive heart failure (P < .0001), pulmonary arterial hypertension (P < .0001), atherosclerosis (P = .01), lupus (P < .0001), scleroderma (P = .009), and chronic pain (P = .006) compared to women with sufficient VitD levels. Interestingly, men with SS and low VitD levels were found to be at higher risk of depression compared to men with sufficient VitD (P = .02), a condition that occurs more often in women. Determining whether sex differences exist in sera VitD levels for patients with SS and whether the levels correlate to autoimmune or CVD is important due to the high occurrence of VitD deficiency in the population and the lack of studies on the role of sex differences in VitD on SS-associated comorbidities.
Maternal Postpartum SSRI Exposure Influences Offspring Neuroinflammation, Neurogenesis, and Microbiome in a Sex-Specific Manner
Wansu Qiu1, Paula Duarte-Guterman, PhD2, Rand Eid1, Yanhua Wen2, Champika Fernando3, Cherie Chang2, Erika Gradeen2, Arianne Albert, PhD4, Janet E. Hill, PhD3, and Liisa A. M. Galea PhD1,2,5
1Graduate Program in Neuroscience, University of British Columbia, Vancouver, Canada
2Department of Psychology, University of British Columbia, Vancouver, Canada
3Department of Veterinary Microbiology, University of Saskatchewan, Saskatoon, Canada
4BC Women’s Health Research Institute, Vancouver, British Columbia, Canada
5Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada
Postpartum depression (PPD) affects 15% of mothers. Selective serotonin reuptake inhibitors (SSRIs) are prescribed to treat PPD. Selective serotonin reuptake inhibitor use during peripartum alters developmental trajectories and gastrointestinal tract in children. Previously, in rats we found an increase in hippocampal neurogenesis in the adult male offspring of SSRI-exposed dams, while decreased in neurogenesis in the adult female offspring of SSRI-exposed dams. Oxytocin (OT) has been found to modulate neuronal development and behaviour, but OT is a large neuropeptide that has difficulty crossing the blood–brain barrier (BBB). TriozanTM is a nanoformulation that can facilitate OT to cross the BBB. Here, we hypothesize that in a rat model of PPD, maternal SSRI will influence neuroinflammation, microbiome composition, and neurogenesis in offspring in a sex-dependent manner and that OT treatment will counteract the effects of maternal treatments. To simulate PPD and SSRI-use, dams were administered corticosterone and/or fluoxetine, a common SSRI, respectively, or vehicle, during the postpartum. Offspring were then exposed to OT (0.5 mg/kg), OT+TriozanTM (0.25 mg/mL; adjusted to 0.5 mg/kg), or vehicle for 10 days (PD25-34). All offspring analyses occur during adulthood (PD 71-73). Data indicate a reduction in both hippocampal pro- and anti-inflammatory cytokines in male and female offspring of SSRI-treated dams. OT+TriozanTM reduced interleukin-5 cytokine levels in both male and female offspring. Microbiome analysis indicated subtle changes to the bacterial community structure only in female offspring of CORT-treated dams. No significant effects of OT in offspring bacterial diversity analyses were found. In addition, a number of sex differences in offspring were seen in abundant bacteria species. Neurogenesis data collection is ongoing. Together, results indicate that maternal SSRI exposure has long-lasting effects on neuroinflammation and microbiome diversity in offspring in a sex dependent manner.
Sex Differences in Comorbidities Associated With Fibromyalgia and Hypermobility Syndromes
Shelby T. Watford1, Katelyn A. Bruno, PhD1, Andrea C. Morales, MD1, Rinald Paloka1, John M. Sousou1, Jenil B. Patel, MD1, Anna A. Mease, MPH1, Nicholas A. Courson2, Peter T. Dorsher, MD3, Todd D. Rozen, MD4, Edsel B. Bittencourt, PT2, Paldeep A. Atwal, MBChB5, Lynsey A. Seim, MD6, and DeLisa Fairweather, PhD1
1Department of Cardiovascular Medicine, Mayo Clinic, FL, USA
2Department of Rehabilitation, Mayo Clinic, FL, USA
3Department of Physical Medicine and Rehabilitation, Mayo Clinic, FL, USA
4Department of Neurology, Mayo Clinic, FL, USA
5Atwal Clinic, FL, USA
6Department of General Internal Medicine, Mayo Clinic, FL, USA
Recent research suggests that chronic pain conditions like hypermobile spectrum disorder (HSD) and hypermobile Ehlers Danlos syndrome (hEDS) occur fairly often in the population with as many as 255 million people affected worldwide. Although many patients have these conditions, the genetic cause and how they relate to other conditions like migraine, depression, fibromyalgia, autoimmune diseases, and heart disease are unknown. Fibromyalgia is an illness associated with chronic pain and estimated to occur in 2% of the population (9:1 women to men). Previous studies examining comorbidities associated with fibromyalgia found that hypermobile syndromes including hEDS occur frequently in fibromyalgia patients (4-25 × more often). In spite of the relatively high prevalence of fibromyalgia and hypermobile syndromes in the population, the pathogenesis of disease and reason for the sex difference remains largely unknown. This project accesses patient information available at Mayo Clinic to examine whether sex and age differences occur in HSD and hEDS and what are the most common conditions associated with these diseases based on ICD-9/10 codes. Comorbidities that were examined include fatigue, migraine, IBS, chronic pain, and depression. We found that females with fibromyalgia had more migraines (P = .0004) and depression (P = .02) compared to males, whereas males had more fatigue (P = .03). When we examined comorbidities according to age using age 50 as a surrogate for menopause status, we found that women under 50 were more likely to have migraines (P = .009) while women over 50 were more likely to have hypertension (P = 5E− 10). We also found that the average number and types of comorbidities vary for each condition. Our findings highlight the importance of studying sex and age and provide insight on factors that may contribute to chronic pain in these patients. Findings from this study will increase understanding of the relationship between fibromyalgia and hypermobile syndromes and may improve our understanding of the pathogenesis of disease.
Sex Differences in Cardiovascular Diseases Associated With Periodontal
Disease Emily R. Whelan1, Katelyn A. Bruno, PhD1, John M. Sousou1, and DeLisa Fairweather, PhD1
1Department of Cardiovascular Medicine, Mayo Clinic, FL, USA
Periodontal disease (Pd) is the inflammation of the oral tissues caused by the presence of pathogenic bacteria in the mouth. Pd affects a large percentage of the population with the most severe cases resulting in alveolar bone loss and recession of the periodontal ligament and other oral tissues. Women with osteoporosis are 3 times more likely to develop Pd after menopause. The pathogenic bacteria that cause Pd can end up in the blood stream and become incorporated into atherosclerotic plaques in coronary arteries in the heart promoting atherosclerosis and/or plaque rupture that lead to a myocardial infarct or stroke. Sex differences exist in both Pd and atherosclerosis with Pd being more dominant in females (53%) and atherosclerosis being more dominant in men (55%). Periodontal disease has been associated with an increased risk of cardiovascular disease, but it remains unclear whether sex differences associated with Pd increase the risk of cardiovascular diseases including atherosclerosis, myocardial infarct, and stroke. In this study, we investigated the association of periodontal disease and various cardiovascular diseases including atherosclerosis according to sex and age. This study utilized the Mayo Clinic electronic medical record database to examine sex and age differences in Pd patients with a diagnosis of atherosclerosis utilizing ICD-9/10 codes. As a control we will examine Pd patients who do not have cardiovascular disease. In an initial analysis, we found a total of 5676 patients (2778 females/2898 males) diagnosed with both atherosclerosis and Pd at Mayo Clinic. Of these 5676 patients, less than 1% of women were under the age of 45 and 0.5% of men under the age of 45. Women over the age of 45 have a slightly decreased chance of having both Pd and atherosclerosis, with men over the age of 45 making up approximately 50% of the patient sample alone. Determining whether Pd influences the risk of developing atherosclerosis, myocardial infarct or stroke according to sex and age is important because this is understudied but could play an important contribution in promoting cardiovascular disease.
Exosomes From Normal Men and Women (PEP) and Premenopausal Women (pmPEP) as Novel Therapies for Myocarditis and Dilated Cardiomyopathy
Anna A. Mease1, Katelyn A. Bruno, PhD1, Paul Stalboerger, MS, PMP2, Anneliese R. Hill1, Atta Behfar, MD, PhD3, Leslie T. Cooper Jr, MD1, and DeLisa Fairweather, PhD1
1Department of Cardiovascular Medicine, Mayo Clinic, FL, USA
2Center for Cardiovascular Medicine, Mayo Clinic, MN, USA
3Department of Cardiovascular Medicine, Mayo Clinic, MN, USA
Viral myocarditis is a leading cause of acute and chronic heart failure with more men progressing from myocarditis to dilated cardiomyopathy (DCM) than women. Currently, no disease-specific therapies exist for this condition. Regenerative medicine therapies have the potential to prevent disease. A standard regenerative therapy uses purified exosome product (PEP) from healthy men and women with no ICD-9/10 codes to prevent or reverse disease. Because estrogen is known to protect women from heart failure, we also examined the effect of exosomes obtained from healthy premenopausal women (pmPEP). We administered human PEP or pmPEP versus PBS control ip to male BALB/c mice around the time of virus injection at day 0 (day −1, 0 and +1) or at a clinically relevant time during myocarditis (day 7, 8, and 9 post infection/pi) and harvested on day 10 pi during peak myocarditis or at day 35 pi during DCM. We found that pmPEP, but not PEP, given during the innate immune response significantly decreased myocarditis (P = .0009) and decreased total immune cells (CD45, P = .008), neutrophils, macrophages and mast cells (CD11b, P = .04), macrophages (F4/80 P = .009), and T cells (CD3, P = .02; CD4, P = .01). When PEP or pmPEP were administered during myocarditis, inflammation was significantly reduced compared to controls (PEP P = .006, pmPEP P = .005) and both therapies significantly decreased remodeling/fibrosis during DCM (PEP P = .02, pmPEP P = .04). Our findings suggest that PEP and pmPEP reduce acute and chronic myocarditis/DCM if administered to patients at the onset of myocarditis, a clinically relevant time point. Future experiments will test the efficacy of PEP or pmPEP in female mice with viral myocarditis. This preliminary data provides preclinical data for an IND application to the FDA to initiate first-in-man studies in patients with myocarditis and DCM.
Anhedonic Behavior and Peripheral Immune Function in Postpartum Rats
Rebecca B. Della Valle1, Nicole A. Haas1, and Jaclyn M. Schwarz1
1University of Delaware, Newark, DE, USA
Changes to the peripheral immune system during pregnancy are well documented, and previous research in our laboratory has demonstrated pregnancy-induced changes to the central immune system as well. What remains less clear is the function of the immune system in the postpartum period, and what effect this might have on depressed mood. Prevalence of post-partum depression (PPD) is estimated at 10% to 15%, and as high as 60% in developing nations. Much of the preclinical research on PPD has focused on the contributions of sex hormones and psychosocial stress, with very little focus on the impact of inflammation. This is despite the growing body of evidence that inflammation may underlie much of the accepted etiology of depression. Previous research in our laboratories has demonstrated that anhedonia in female rats immediately after parturition is associated with elevation of the pro-inflammatory cytokine IL-6 in the medial prefrontal cortex and hippocampus, and that this anhedonic behavior is rescued by treatment with an IL-6 receptor antibody. The current project aims to extend this research by examining postpartum immune function more broadly, and addressing questions regarding the robustness of postpartum anhedonic behavior. In experiment 1, we are examining peripheral expression of inflammatory cytokines and chemokines at multiple time points throughout pregnancy and the postpartum period in primiparous Sprague Dawley rats, to develop a time course for immune function that might help explain postpartum anhedonic symptoms. In experiment 2, we are conducting a modified version of sucrose preference test to rule out any contribution of pup-separation to previously demonstrated postpartum anhedonia, as well as testing for sucrose preference in multiparous rats to determine whether postpartum anhedonia is unique to first-time mothers. These experiments will provide new insight for directing preclinical research of PPD, an understudied and uniquely female disorder.
Sex Differences in Symptoms of Obstructive Sleep Apnea (OSA) in Community-Dwelling Adults With Type 2 Diabetes (T2D)
Jonna L. Morris1, Susan M. Sereika2, and Eileen R. Chasens2
1Department of Psychiatry, University of Pittsburgh, School of Medicine, Pittsburgh, PA, USA
2Department of Health & Community Systems, University of Pittsburgh, School of Nursing, Pittsburgh, PA, USA
Women, including those with T2D, are underdiagnosed for OSA despite evidence of increased risk. It has been suggested women may be underdiagnosed because they are more likely than men to report impaired mood in the presence of OSA, instead of traditional symptoms (eg, daytime sleepiness, poor daytime function, poor sleep quality). The purpose of this secondary analysis was to explore sex differences in relations between OSA severity and OSA symptoms in community-dwelling adults with T2D. This study used a cross-sectional design of baseline data from the DSTT trial. The sample (N = 322, 50.9% male) with T2D (mean [±SD] of A1C 8.0% ± 1.8%) was racially diverse (42% African American) and on average 56.5 ± 10.5 years of age. Measures included a home sleep study to determine OSA severity (apnea-hypopnea index [AHI]) and a questionnaire battery (Pittsburgh Sleep Quality Index [sleep quality], Profile of Mood States [mood], Functional Outcomes of Sleep Quality [functioning], and Epworth Sleepiness Scale [daytime sleepiness]). Covariates included BMI, serum glucose(A1C), age, race, perceived financial ability, and marital status with sex as a moderator. Linear regression explored relations of AHI with OSA symptoms and interactions of sex with AHI. Women reported poorer sleep quality (P < .05), yet men had worse AHI (P < .05). In fully adjusted models, sex did not moderate the relations of AHI with OSA symptoms (P ≥ .05). Negative perceived financial ability, African-American race, and younger age were associated with worse mood, daytime function, and sleep quality; worse AHI was not associated with OSA symptoms (P ≥ .05). In conclusion, in a sample of adults with T2D, participants who were younger, African-American, and perceived worse financial ability reported worse mood, sleep quality, and daytime function, with no contribution of AHI or moderation by sex. Impaired mood may be speciously considered a symptom characteristic of OSA in women.
Stress Exposure in Intact and Ovariectomized Mice: Divergent Neural Signatures Despite Similar Behavioural Outcomes
Rand S. Eid1, Sarah J. Wong1, Stephanie E. Lieblich1, and Liisa A. M. Galea1
1University of British Columbia, Vancouver, British Columbia, Canada
Depression affects approximately twice more women than men. A focus on female-specific factors that can determine risk or resilience to depression is thus warranted, but largely ignored. Fluctuations or reductions in ovarian hormones associated with events such as childbirth or perimenopause contribute to depression vulnerability, but the underlying neurobiological mechanisms are poorly understood. Here, we used a stress-based model of depression in intact and ovariectomized (OVX) mice and examined the behavioural and neuroinflammatory consequences of stress exposure. Further, we investigated intracellular signaling pathways (MEK and ERK) that may mediate the actions of ovarian hormones under stress exposure. We hypothesized that intact mice will show behavioural resilience to stress, and that ovarian status will determine the neural consequences of stress exposure. Briefly, intact and OVX mice were assigned to non-stress groups or exposed to 6 days of variable stress. Mice were tested for depressive-like behaviour, and the hippocampus and prefrontal cortex (PFC) were dissected for quantification of cytokines and intracellular signaling proteins. The behavioural outcomes of stress exposure were similar between ovarian status conditions, with increased anhedonia-like behaviour in the sucrose consumption test, and surprisingly, decreased passive-coping behaviour in the forced swim test. Intriguingly, despite these similar behavioural profiles, the neural signatures of stress, particularly in the PFC, were significantly different in intact and OVX mice. Namely, stress increased interleukin-1β, an important mediator of the inflammatory response, in the PFC of intact but not OVX mice. Further, stress decreased phosphorylated MEK and ERK in the PFC of intact mice but increased the same proteins in OVX mice. Thus, ovarian hormone status can influence the pathophysiology of depression and should be considered in efforts toward personalized treatment in women.
The Impact of Motherhood and APOE Genotype on the Aging Brain
Bonnie Lee1, Paula Duarte-Guterman1, Muna Ibrahim1, Rand S. Eid1, Stephanie E. Lieblich1, Nicole C. Minielly1, Daria Tai1, Yanhua Wen1, and Liisa A. M. Galea1
1University of British Columbia, Vancouver, British Columbia, Canada
Women are more likely to be diagnosed with Alzheimer Disease (AD) and show greater AD neuropathology and cognitive decline compared to men. Pregnancy and motherhood (parity) play important roles in the aging brain; increased parity is associated with a greater risk of dementia, AD, neuropathology, and an earlier age of AD onset. Research in our laboratory has shown that parity influences hippocampal neuroplasticity and cognition in middle-aged rats. APOE4, a major genetic risk factor for AD, has been shown to interact with parity to influence AD pathology, age of AD onset, and cognition. The objective of this project is to determine how previous parity interacts with APOE genotype to influence cognitive decline in older female rats. We used a rat model of AD that expresses the human form of APOE4. Age-matched APOE4 and wild-type female rats were either nulliparous (never mothered and with no sexual experience) or primiparous (first time mothers). The primiparous (WT and APOE4) female rats were bred at 5 months old in our animal facility. Pups were culled and the sex ratio of the litters were recorded. Maternal observations were completed twice a day, on days 2 to 6 postpartum. All rats were aged and then trained and tested during middle-age (9 months postpartum; equivalent to 13-14 months old) on the delayed win-shift radial arm maze (RAM), a spatial working memory task mediated by the prefrontal cortex and hippocampus. I am currently analyzing the data for this study. It is hypothesized that APOE4 primiparous rats will perform worse than APOE4 nulliparous rats, and APOE4 rats will perform worse than wild-type rats, in the RAM. It is further hypothesized that APOE4 genotype interacts with parity to contribute to cognitive decline. These results offer insight into how parity and genotype are linked to cognition. This has implications for the importance of tailored treatments based on the genotype and reproductive history of women with AD.
Sex Differences in the Effects of Kappa Opioid Receptor Ligands on Behavior Relevant to Depression in Mice
Moriah L. Jacobson1, Hildegard A. Wulf1, Caroline A. Browne1, and Irwin Lucki1
1Uniformed Services University
Major depressive disorder (MDD) is a leading cause of disability worldwide. Available treatments have limited efficacy, with a large proportion of patients being treatment resistant. The endogenous opioid system is dysregulated in MDD. Kappa opioid receptors (KORs) are a target for developing new treatments because activation of KORs produces negative affect, and KOR blockade exerts behavioral effects in tests relevant to antidepressants. Because women are twice as likely as men to be diagnosed with MDD, it is important for preclinical studies to incorporate the evaluation of sex differences. In these studies, we investigated sex differences in response to KOR ligands in C57BL/6J mice. We employed evaluation of nest building behavior as an ethologically relevant indicator of overall well-being. We had the following hypotheses; (1) Selective KOR activation by U50,488 (U50) will suppress nesting; and (2) JNJ-67953964 (previously LY2456302 and CERC-501), a selective KOR antagonist, will block U50-induced nesting suppression. First we found that U50 (5 or 10 mg/kg, ip) suppressed nesting behavior, but females required a higher dose than males. Second, JNJ-67953964 (1, 3, or 10 mg/kg, ip) given 24 hours prior to testing, blocked the effects of U50 on nesting. Again, females required higher doses than males. Ongoing studies are addressing the roles of estrogen, dynorphin secretion, KOR receptor availability, and signaling in mediating these findings. Our results demonstrate that nesting is a useful test to assess compounds that engage with KOR. Our data also encourage further clinical development of JNJ-67953964 as a therapeutic for MDD. Our results support the existence of sex differences in KOR activation and sensitivity, and indicate that females will potentially require a different dosing regimen than males. A more thorough understanding of sex-biased mechanisms in response to KOR ligands would be helpful in developing more effective, sex-specific treatments for MDD.
Sex and Age Influence in Behavioral and Hippocampal Interleukin-6 Changes in the Two-Hits Animal Model of Schizophrenia Induced by Neonatal Immune Activation Combined With Peripubertal Stress
Tatiane da Silva Araujo1, Camila Nayane de Carvalho Lima1, Rafaela Carneiro Cordeiro1, Maria Gabrielle Oliveira e Silva Linhares1, Francisco Eliclecio Rodrigues da Silva1, Germana Silva Vasconcelos1, Aline Santos Monte2, and Danielle Macêdo Gaspar1
1Universidade Federal do Ceará
2Universidade da integração internacionl da lusofonia afro-brasileira–UNILAB
Schizophrenia (SCZ) is a severe mental illness characterized by positive (PS) as delusions and hallucinations, negative (NS) as social withdrawal and cognitive symptoms (CS). Schizophrenia presents sex influences in its onset and symptoms severity with men presenting earlier onset of symptoms. Perinatal immune challenge combined with pubertal stress are important risk factors for SCZ, being called the 2-hit model. Our first aim was to determine behavioral alterations related to SCZ symptoms, in both sexes mice exposed to neonatal immune challenge with poly I: C (PIC) with peripubertal unpredictable stress (PUS) in ages related to human late adolescence (postnatal day [PN] 50) and adulthood (PN70). Next, we evaluated changes in hippocampal IL-6. Male and female Swiss mice on PN5-7 received PIC (1 mg/kg, IP). This period corresponds to human last trimester of gestation. On PNs 35 to 43 mice were exposed to PUS. Behavioral determinations included pre-pulse inhibition (PPI) for PS, social interaction for NS and Y maze for CS, performed on PNs 50 and 70. Statistical analyses were done by 2-way ANOVA followed by Tukey test, P < .05. Controls received sterile saline during neonatal age being maintained undisturbed in adolescence. The study was approved by the local ethics committee. Two-hit male mice presented 17% PPI deficit on PN50 and 29% on PN70. In 2-hits females this reduction was only on PN70 (30.4%). Memory deficits and social isolation were observed in both sexes and ages. IL-6 was increased in males on PN50 and 70 and in females on PN70. Thus, in early ages, male and female mice present distinct symptoms of SCZ with male animals presenting all symptoms while females only with negative- and cognitive-like ones. These results are of great importance since SCZ is diagnosed based on positive symptoms. Possibly the disorder is underdiagnosed in adolescent females due to sex differences in the symptoms and not on age onset. Hippocampal IL-6 was related to PPI deficits.
Influence of Sex on Respiratory Morbidity in Cystic Fibrosis Pulmonary Exacerbations
Kristina Montemayor, MD1, Kevin Psoter, PhD1, Noah Lechtzin, MD, MHS1, and Natalie West, MD, MHS1
1Johns Hopkins University School of Medicine, Baltimore, MD, USA
Cystic Fibrosis (CF) is a disease with equal prevalence across sexes, but prior studies have shown that women have worse outcomes, such as increased mortality. It is well-known that pulmonary exacerbations (PEx), described as an increase in respiratory symptoms coupled with a provider’s decision to treat with oral and/or intravenous antibiotics, in CF patients can lead to decreased lung function, lower quality of life, and shortened survival. However, there is sparse data evaluating how sex influences respiratory morbidity in CF. Thus, the aim of our study was to determine the proportion of women having a CF PEx from our local cohort, as well as to identify factors associated with those women who had a PEx. We hypothesized that women have a higher proportion of PEx per year compared to men. We conducted a retrospective cohort study evaluating CF patients ≥ 18 years of age who were seen in the Johns Hopkins Adult CF Center from June 15, 2016, to June 15, 2017 (n = 288). There were 142 women and 146 men included in the analysis. Among the women, 42.3% (n = 60) had at least 1 PEx per year compared to 21.9% of men (n = 32) (P < .001). Participants were further stratified by number of PEx per individual. Among women, 56 had 1-2 PEx per year and 4 had > 2 PEx. Among men, 29 had 1-2 PEx per year, and 3 had >2 PEx (P = .003). Women were further stratified based on PEx occurrence, and cohort characteristics were obtained. Women with a PEx had a lower BMI compared to those women without a PEx (22.3 vs 24.4 kg/m2, respectively; P = .03). Additionally, 56.7% of women with a PEx had a history of CF-related diabetes compared to only 31.7% of those women without a PEx (P = .003). From our single-center study, we conclude that women had a statistically significant higher percentage of PEx. Future research will be directed at evaluating sex-based differences in respiratory morbidity and mortality in CF PEx from a national cohort.
Maternal Health Outcomes of Incarcerated Women: A Systematic Scoping Review
Martha Paynter, PhD(c), RN1,2, Emily Drake, MA1, Christine Cassidy, PhD, RN2, and Erna Snelgrove-Clarke, PhD, RN1,2
1Dalhousie University School of Nursing, Halifax, Nova Scotia, Canada
2IWK Health Centre
Sex Differences in Hematopoietic Responses to Dietary Obesity
M. Varghese1, S. Abrishami1, C. Griffin1, and K Singer1
1Department of Pediatrics, University of Michigan, Ann Arbor, MI, USA
Obesity is a global health epidemic, closely associated with cardiovascular diseases, hypertension, type 2 diabetes, and atherosclerosis. Obese men have a higher incidence of these conditions compared to premenopausal women. Sex differences in adipose tissue distribution, obesity-induced inflammation, and myeloid cell activation are tightly linked to insulin resistance. In male mice fed a high-fat diet (HFD), adipose tissue is a major source for inflammation exhibiting profound adipose tissue macrophage (ATM) accumulation in gonadal white adipose tissue (GWAT). However, it is not clear whether sex influences inflammatory responses and hence metabolism. We hypothesized that young females fed a HFD would have dampened inflammation which directly explains reduced metabolic and cardiovascular disease in young women. We challenged male and female C57Bl6/j mice to 16 to 24 weeks of 60% HFD starting at 6 weeks of age (young) or 10 month of age (old). Body weight and metabolic depot (adipose and liver) weights were measured at the completion of diet challenge. Flow cytometry was used to determine ATM populations. Lipolysis was stimulated with a beta3 adrenergic receptor (ADRB3) agonist and free fatty acids (FFA), glycerol, and triglyceride levels assessed in serum and liver. Monocyte transfer experiments and in vitro myeloid assays were performed to further evaluate programmed changes in myelopoiesis. High-fat diet in young mice led to fat accumulation in GWAT and IWAT of both males and females. In old male animals, fat pads did not expand, and liver weights were as a result larger than in females. Young and old females had reduced ATMs, monocyte production, and myeloid progenitors compared to males. Sex differences in ADRB3 activation were observed with females depicting elevated FFAs compared to levels induced in males. Female monocytes transferred into male mice and in in vitro myeloid assays had dampened responses to saturated fatty acid exposure. Our results demonstrate that sex differences in obesity-induced inflammation even with aging might explain sex differences in metabolic and cardiovascular diseases and need to be further explored for targeted treatment strategies.
The Impact of the Testosterone to Estrogen Ratio and Cardiometabolic Health in Transwomen
Michael Nelson1, Deborah Clegg2, and Cedar-Sinai3
1University of Texas, Arlington, TX, USA
2American University, Washington, DC, USA
3Medical Center, Los Angeles, CA, USA
Cardiovascular disease (CVD) is the leading cause of death in the United States. The incidence of CVD and resultant morbidity and mortality is lower in premenopausal women compared to age-matched men. This “sex advantage” influences endothelial function and inflammation, with women having less endothelial dysfunction and lower levels in systemic inflammation when compared to men. Female protection from CVD disappears after menopause, implicating both age and estrogens as the primary sources of cardioprotection. However, estrogen therapy in men and postmenopausal women has proven equivocal with respect to CVD risk, and this is partly confounded by age, chromosomes, and potentially other hormones such as testosterone. To begin to fill this knowledge gap, our group recently evaluated the metabolic health of young transwomen—men who identity as women—who are chromosomally male, but are taking cross-sex hormones to achieve the desired sexual characteristics of a female. In the United States, there is an estimated 8 million people (0.2% to 0.3% of the population) living with gender identity disorder, and these individuals opt for interventions and procedures aimed at alleviating the incongruence between their gender identity and their biological chromosomal and gonadal sex. For transwomen, this entails suppressing endogenous testosterone (T) while supplementing with exogenous estradiol (E). Remarkably, the second leading cause of death in transwomen is CVD, and out data demonstrate imbalance between T and E in the chromosomal background of men is a major contributor to CVD risk. Our data suggest that, regardless of similar E therapy, transwomen who elected for bilateral orchiectomy had improved metabolic health when compared to those transwomen who retained their testes. More specifically, when the transwomen who retained their testes were stratified according to circulating T levels, those with the highest T also had the greatest level of hepatic steatosis and insulin resistance. Our data support the notion the ratio of T and E is the critical factor for determining CVD risk in males, females and transwomen, rather than the presence or absence of the gonadal hormones per se.
The Role of Human Chemosignals in Eliciting a Stress Response
Laila Chaudhry1, Sioui Maldonado1,2, Gabrielle Dutra1, and Jeffrey S. Mogil1
1McGill University, Montreal, Quebec, Canada
2Université de Montréal, Montreal, Québec, Canada
Our laboratory recently demonstrated that mere olfactory exposure to male experimenters can trigger stress-induced analgesia in rodents. Male sweat and certain volatile chemosignaling compounds found therein—(E)-3-methyl-2-hexenoic acid (3M2H), androstenone, and androstadienone—were shown to cause reduction in pain behaviours and increases in corticosterone. This stress response to male chemosignals was also found to be concentration-dependent and particularly robust in female rodents. Androstenone and androstadienone have also been shown to raise cortisol levels in human women but not in men, for approximately 1 hour following olfactory exposure. 3M2H’s concentration in sweat is far higher than that of both androstadienone and androstenone, and although it has been studied far less than the other 2 compounds, it is reasonable to predict that 3M2H will produce a similar reaction effect: stress and stress-induced analgesia in humans, particularly in women. In the current stage of our study, we are confirming that 3M2H does indeed alter stress levels in a sex-dependent manner. Participants are exposed to 3M2H via an olfactometer, their mood and anxiety reported via visual analog scales, and their cortisol collected via saliva samples. We have observed significant sex differences, with males showing a drop in cortisol levels after exposure to high concentrations of 3M2H, while women’s cortisol levels remain unchanged. We believe that the robust sex differences displayed in stress responses might have important implications for the design of all human laboratory experiments, and possible clinical relevance to a number of mental disorders ranging from anxiety to depression to post-traumatic stress disorder, all of which occur more often in women, and thus its explication may make unique contributions to women’s health.
Are We Assessing for Gender Equity Outcomes in International Development Evaluation?
Steven Lam1, Warren Dodd2, Jane Whynot3, and Kelly Skinner2
1Department of Population Medicine, University of Guelph, Guelph, Ontario, Canada
2School of Public Health and Health Systems, University of Waterloo, Waterloo, Ontario, Canada
3Institute of Feminist and Gender Studies, University of Ottawa, Ottawa, Ontario, Canada
Gender equity is an increasingly discussed priority within international development programs and policies. However, it is unclear whether advances being made in assessing for gender equity outcomes are reflected in the scholarly literature. In this context, we ask: how is gender being addressed in the evaluation of international development efforts? To answer this question, we conduct a meta-evaluation of peer-reviewed evaluation studies, analyzing a total of 70 relevant studies. Of the reviewed evaluations, most focused on the health sector (73%) and targeted gender-specific programs (63%). While the number of studies that report on gender is growing, often only outcomes by “women” and “men” were considered without going further to account for gender equity. Furthermore, a limited number of evaluation studies reported on engagement with evaluation stakeholders (9%), recommendations to address gender inequity (9%), or outcomes for gender-diverse individuals (1%). These findings suggest that the inclusion of gender in evaluations does not automatically lead to analysis or reporting of transformational aspects. Opportunities for evaluation to contribute to gender transformative changes include assessing outcomes of diverse groups of genders, engaging with evaluation stakeholders, encouraging the use of evaluations, and providing actionable recommendations.
The Gender Binary in Nature, Across Human Cultures, and in the Bible
Joan Roughgarden1,2
1Stanford University, Stanford, CA, USA
2University of Hawaii, HI, USA
The animal kingdom offers no support for a natural universal distinction between male and female sexual categories for whole organisms. Nor does the animal kingdom support the universal existence of 2 fixed genders within species. The discovery of extensive variation in gender expression and sexuality in nature challenges traditional biological explanations of animal behavior, especially accounts that trace to Darwin’s theory of sexual selection. Variation in human gender expression and sexual orientation occurs among people in all cultures throughout the world. All cultures have indigenous institutions and norms to accommodate the natural variation in the human species. The Bible in both the Hebrew and Christian Testaments contains inclusionary reference to human variation in gender expression and sexuality. The famous baptism of an Ethiopian eunuch by Phillip the Evangelist in Acts 8:26—38 is a particularly important injunction to promote full inclusion of gender-variant people into all aspects Christian ministry.
Sex-Specific Autosomal DNA Methylation in the Human Placenta
Amy M. Inkster1, Victor Yuan1, Chaini Konwar1, Allison M. Matthews, PhD1, Carolyn J. Brown, PhD1, and Wendy P. Robinson, PhD1
1Children’s Hospital Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
Male sex is a risk factor for many perinatal complications. Pregnancies carrying male fetuses are at higher risk of spontaneous preterm birth, fetal growth restriction, and late-onset maternal preeclampsia. Healthy pregnancies also display sex differences in fetal development and placental function. Molecular features of the placenta such as DNA methylation (DNAme) may reveal mechanisms underlying sex differences. We hypothesize that, in addition to differences on the X-chromosome, sex-specific autosomal DNAme exists in the placenta and is related to sex differences in placental function and fetal health. We assembled data from 341 healthy placentae >37 weeks gestation (51% female) from 5 public Illumina HumanMethylation 450K data sets (GSE73375, GSE74738, GSE75248, GSE100197, GSE1008567). We filtered and normalized DNAme data, and identified sex-specific differentially-methylated (DM) sites by linear modelling. We replicated DM analyses in 2 additional data sets (GSE70453, GSE115508). We identified sex-specific placental DNAme at 166 autosomal sites out of 324 104 sites tested; 92% of 166 showed male hypermethylation. DM replicated at 7 sites, all male hypermethylated; 3 DM sites were in the promoter of ZNF300, expression of which may be inversely related to risk of preeclampsia and fetal growth restriction. Additionally, ZNF300 binding sites are found in immune genes such as IL-2 and IL2RB. The 84 genes associated with the 166 DM sites showed enrichment in chemokine-mediated signalling pathways, eosinophil chemotaxis, peptide cross-linking, and cornification, suggesting a potential role for immune pathways in placental sex differences. The detected sex-specific autosomal DNAme is consistent with sex differences in perinatal development, and provides a means of identifying candidate genes/regions involved in differential placental function, fetal development, and male susceptibility to perinatal complications.
Incorporating Sex and Gender in the Evaluation of Mobile Health Applications
Janessa Griffith1
1University of Toronto and Women’s College Hospital Institute for Health System Solutions and Virtual Care
The author developed the first iteration of an evaluation tool to assess the extent to which mobile health applications (apps) are inclusive to users of all sexes and genders. The tool guides evaluators to question whether the features of or information on the app reinforce sex or gender stereotypes, the assumptions the app is making about the user and implied values. The author used this tool to evaluate a menstrual tracking app that was rated as in the top 2 in a study published in the American College of Obstetricians and Gynecologists as well as a website that hosts evaluations of apps by physicians. The author applied the evaluation tool to each of the pages available in the app. Through the evaluation, several areas to improve upon were identified. For example, upon registering for a new account, the user does not need to enter their sex or gender. However, the sex category (mislabelled as “gender”) held a default value of “female,” without the researcher entering this information. The only category options were “male” and “female” and this is a mandatory field. This could either be replaced with the label of “sex” or the options could be changed to include all gender identities. Additionally, if a user entered “male,” different profile information is requested, including household income and zip code. It is unclear why these categories would only be present if one identifies as “male” and there is no information about this available. Meanwhile, female users are asked about birth control methods, but not male users. Although this app was rated highly, it was not evaluated for sex and gender inclusivity and could perpetuate gendered discourses. Incorporating a tool to evaluate apps for sex and gender considerations could promote inclusivity. Further research is necessary to refine and test the evaluation tool.
Sex-Specific Regulation of Immune Cell Function by the Histone Demethylases KDM5c/d
Mario Corrado, MSc1,2, and Connie M. Krawczyk, PhD1,2
1Department of Physiology, Goodman Cancer Research Center, Montreal, Quebec, Canada
2Van Andel Research Institute, Grand Rapids, MI, USA
Sex differences in immune function have been well-documented; females mount a more potent response than males. However, the molecular mechanisms that account for sex-specific immune response remain poorly understood. Dendritic cells (DCs) cells of the innate immune system are among the first responders to any immune stimulus and play a key role in determining the nature and extent of the ensuing immune responses. Upon detection of an activating stimulus, DCs transition from the “steady state” to an activated state capable of instructing antigen-specific immune responses. Our lab studies the active maintenance of the steady-state, which is essential for maintenance of immune homeostasis and induction of productive immune responses. We found that the X-linked H3K4 histone demethylase, KDM5c (JARID1c), regulates steady-state function of DCs. KDM5d (JARID1d), the Y-linked paralogue of KDM5c, is also expressed in DCs, however does not show that same regulation of KDM5c. Our work on the role of KDM5c and KDM5d and their contribution to sex differences in immune responses will be presented.
Differences in Discontinuation of Statin Treatment in Women and Men With Advanced Cancer Disease
Helena Bergström1, Elsa Brånvall2, Maria Helde-Frankling1, and Linda Björkhem-Bergman1
1Division of Clinical Geriatrics, All Karolinska Institutet, Stockholm, Sweden
2Division of Clinical Epidemiology, All Karolinska Institutet, Stockholm, Sweden
Statins are often discontinued in patients with advanced cancer since the net effect of treatment is considered negative. However, guidelines concerning discontinuation of statin treatment are lacking. The aim of this study was to investigate any differences in time of discontinuation of statin treatment between men and women with advanced cancer disease. Medical records from 195 deceased palliative cancer patients from a previous study cohort were reviewed. Patients treated with statins 2 years before death were identified as “statin users.” The time of discontinuation of statin therapy was identified and correlated to time of death. Only patients who had incurable cancer disease at time of statin discontinuation were included in the analysis. Fifty-four patients were identified as statin users, 29 women and 25 men. The average time span between discontinuation of statin treatment and time of death was significantly longer in women than in men, 10 months compared to 4 months (P < 0.01), with a range of 1 to 24 months among women and 1 to 12 months for men. All patients died due to cancer disease. More men than women had a history of stroke or cardiac infarction (P = .02). There were no differences in age, socioeconomic factors, or survival time from study inclusion between men and women. There was no difference in self-assessed quality of life (QoL) between statin users who had discontinued statin treatment and those who are still on treatment. Men generally assessed their QoL lower than women in this study (P = .03). Statin treatment was discontinued earlier in women than in men in patients with advanced cancer. The data suggest that statins may be discontinued earlier in men as well, since earlier discontinuation did not affect cardiovascular mortality.
Sex-Specific Studies in Parkinson’s Disease Models for Gonadal Drug Repurposing
Amandine Isenbrandt1,2, Jérôme Lamontagne-Proulx, MSc1,2, Mélanie Bourque, PhD1, Katherine Coulombe, MSc1, Marc Morissette, PhD1, Thérèse Di Paolo, PhD1,2, and Denis Soulet, PhD1,2
1Centre de recherche CHU de Québec Université Laval, Quebec, Canada
2Université Laval, Quebec, Canada
Prevalence and incidence of Parkinson disease (PD) are higher in men than women, which suggests a possible role of sex hormones in neuroprotection. Dutasteride (DUT), a 5α-reductase inhibitor has neuroprotective effects in PD mouse models and could be affected by sex hormones. It can act indirectly by increasing endogenous estrogen levels through its inhibition of the 5α-reductase, which will block the conversion of testosterone and progesterone. Without testosterone conversion, it will accumulate and will be able, in part, to be converted into estrogen by the enzyme aromatase. Dutasteride can also act directly through its interaction with the mitochondrial adenyl nucleotide translocator (ANT). Four groups of mice, male or female, will be gonadectomized (GDX) or not (SHAM). These mice will be treated with DUT or vehicle for 10 days and treated with MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) or vehicle on the 5th day. MPTP is used to cause an early-stage PD model in our study. Then, the brains and intestines will be collected and analyzed to observe MPTP alterations and inflammatory activity. Differences between female and male SHAM mice treated with MPTP are expected. 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine should cause neurodegeneration and inflammation, and DUT is expected to reduce these effects. Regarding DUT’s mode of action, there are 2 possibilities: if it acts through the inhibition of 5α-reductase, there would be a stronger neuroprotection in SHAM males. If it is mediated by the ANT, no visible difference between the SHAM and GDX groups should be seen. This project will provide a better understanding of the role of sex hormones in the development of PD. It will also allow to observe their impact on DUT’s neuroprotective properties and have a more precise idea of DUT’s target and mode of action.
Sex Differences and the Role of Selective Estradiol Receptor Subtypes in Neural Mechanisms of Addiction
Jill B. Becker, PhD1, Katie E. Yoest, PhD1, Jacqueline A. Quigley, MS1, and Jennifer A. Cummings, PhD1
1University of Michigan, Ann Arbor, MI, USA
Variable Stress Induces Sex Specific Effects on Microglial Morphology in the Nucleus Accumbens Core and Shell
Mariya Tsyglakova1, Jennifer R. Rainville1, Amanda N. Patterson1, Brett H. Smith1, and Georgia E. Hodes1
1Graduate Program in Translational Biology, Medicine and Health, and School of Neuroscience, Virginia Tech
Depression and anxiety are common and debilitating mood disorders that are more prevalent in females than males. Stress is a trigger for many mood disorders and has effects on plasticity in the nucleus accumbens (NAc) a part of the brain’s reward circuitry. We previously showed that 6 days of variable stress (SCVS) sex specifically regulates plasticity in NAc. SCVS induced a behavioral stress response in females but not males, whereas 28 days of chronic variable stress (CVS) triggered depression-associated behavior in both sexes. Microglia are implicated in regulating neuronal plasticity during development and in disease states. We hypothesize that 6 and 28 days of variable stress will induce microglial activation in a sex-dependent manner. To characterize the effects of stress on microglia, we examined microglial number, density, and morphology in the NAc core and shell regions of male and female mice. Variable stress consisted of 3 different stressors: foot shock, restraint tube, and tail suspension. Each stressor was administered for 1 hour, and stressors alternated each day for either 6 (SCVS) or 28 (CVS) days. We then used immunohistochemical analysis for expression of Iba1, a constitutively expressed calcium-binding protein specific for microglia, in the NAc core and shell regions. We found opposite effects of stress on microglia number in the NAc in males and females after 6 and 28 days of variable stress, that were driven by the changes in the core. Females had a more activated profile of microglia, as the ratio of primed to surveillant microglia significantly increased in females following 6 days of stress, where in males, stress had no significant effect on this ratio. These data suggest that stress has sex and region-specific effects on microglia morphology and number which potentially modulate sex specific effects of neuronal plasticity and the higher rate of mood disorders in females.
Prediction of Drug Metabolism From Hepatic Transcript Profiles
James C. Fuscoe1, Vikrant Vijay1, Joseph Hanig2, Tao Han1, Lijun Ren1, and Qiang Shi1
1National Center for Toxicological Research, US Food and Drug Administration, USA
2Center for Drug Evaluation and Research, US Food and Drug Administration, USA
We hypothesized that hepatic transcript profiles of drug metabolism enzymes (DMEs) could be used to predict sex-and/or age-associated differences in drug metabolism and possible adverse events. Existing whole genome hepatic transcription profiles in F344 rats were used to test this hypothesis. Large differences were observed in the expression of hepatic genes in F344 rats during their life spans and also between the sexes. In adult rats, 29 of 298 genes that code for hepatic DMEs were found to have sexually dimorphic expression, including 4 cytochrome P450 (Cyp) enzymes. Using PharmaPendium, a compilation of FDA drug approval information, 41 drugs were found to be metabolized by 1 or 2 Cyp enzymes encoded by sexually dimorphic mRNAs. Primary rat hepatocytes were used to evaluate the metabolism of 11 of these drugs. The sexually dimorphic expression of the 4 Cyp genes was measured in the primary rat hepatocytes and closely matched the in vivo hepatic expression: Cyp2c7, F>M; Cyp2c11, Cyp3a2, and Cyp3a62, M>F. Liquid chromatography/tandem mass spectrometry was used to evaluate the pharmacokinetics of the drugs. Three of the drugs (doxorubicin, irinotecan, and phenytoin) had long half-lives and were not appreciably metabolized during the 2 hour incubation period, and one drug (tazarotene) was rapidly and predominantly metabolized by esterase whose expression was not sexually dimorphic. Of the remaining 7 drugs (azelastine, buspirone, fentanyl, glimepiride, pravastatin, tamsulosin, and terfenadine), all except for pravastatin showed the predicted sexually dimorphic metabolism. The 41 drugs were generally not toxic, with 1 drug (terfenadine) showing predicted sex-different cytotoxicity. Thus, in this rat model, transcript profiles allowed identification of sex-related differences in drug metabolism. Therefore, human hepatic transcript profiles may allow evaluation of metabolism and possible toxicity of drugs in susceptible populations.
Sex Differences in Progesterone Receptor Expression in Developing Brain: From RNA Sequencing to Aggressive Behavior
Christine K. Wagner1, Diana Lalitsasivimol1, Deena Walker2, and Eric Nestler2
1University at Albany, Albany, NY, USA
2Icahn School of Medicine at Mount Sinai, Mount Sinai, NY, USA
Many neurodevelopmental behavioral disorders demonstrate significant gender biases, and yet the fundamental mechanisms underlying sex differences in brain development are not completely understood. A sex difference in nuclear progesterone receptor (PR) expression exists in the medial preoptic nucleus (MPN) of rats and mice during development. Males express high levels of PR through much of perinatal development, the result of induction of PR expression by the testosterone metabolite, estradiol acting at estrogen receptor α. In contrast, PR expression in females is virtually absent until the second postnatal week. This represents one of the earliest and largest sex differences reported in the mammalian brain and suggests the existence of a developmental window during which the male MPN is more sensitive to progestins than the female MPN. Sex differences in PR expression during development may result in differential gene expression in males and females. Using RNA sequencing, we identified 195 genes that were differentially expressed (1.5-fold) in postnatal day 7 MPN of progesterone receptor knockout (PRKO) and wild-type (WT) mice, 91 of which contained a progesterone response element (PRE). Of particular interest, 2 genes involved in serotonergic synaptic function were differentially expressed in PRKO and WT; serotonin transporter (slc6a4) and serotonin receptor 2a (htr2a) were downregulated in PRKO males compared to WT males. Interestingly, intermale aggression, which is regulated by serotonergic activity in the MPN, was diminished in PRKO males compared to WT males in adulthood. Furthermore, neonatal testosterone (T) treatment failed to masculinize adult aggressive behavior in PRKO females compared to T-treated WT females. These findings implicate PR in the sexual differentiation of the MPN and challenge the dogma that androgen and estrogen receptors are exclusive players in sexual differentiation of the brain.
PWV response to angiotensin II challenge as a function of adiposity measures, by sex.
Sex-Dependent Effects of Prediabetes in Mouse Models of Alzheimer’s Disease and Mixed Dementia
Lisa S. Robison1, Olivia J. Gannon1, Abigail E. Salinero1, Melissa A. Thomas1, and Kristen L. Zuloaga1
1Albany Medical College, Albany, NY, USA
Alzheimer’s disease (AD) and vascular dementia are the 2 most common forms of dementia, and it has been estimated that 60% of individuals with AD have underlying cerebrovascular pathology/mixed dementia (MxD). Diabetes increases the risk for both vascular and nonvascular dementia (including AD), though less is known about the effects of prediabetes. This is a critical gap in knowledge, as prediabetes affects 38% of Americans. Prediabetes has been linked to early indicators of dementia, including hippocampal atrophy and memory deficits, though further exploration of its effects on AD and MxD in particular are necessary. Since females have higher rates of dementia and faster rates of cognitive decline, sex differences were explored. Male and female 3 × Tg-AD mice received either sham (AD model) or right unilateral common carotid artery occlusion (rUCCAO) surgery (MxD model) at ∼2.5 months of age; these were compared to wild-type (WT)/sham surgery (control) mice of both sexes. rUCCAO reduced blood flow to the right hemisphere by ∼20% immediately after surgery. Mice were then placed on either low-fat (LF; 10% fat) or high-fat (HF; 60% fat; prediabetes model) diet for 3 months, then used to assess outcomes of metabolism, behavior/cognition, and pathology. High-fat diet increased body weight gain and visceral fat mass, and impaired glucose tolerance, across groups, though these metabolic deficits were greatest in 3 × Tg-AD mice (AD and MxD models) females. High-fat diet did not affect novel object recognition performance in WT mice; however, most AD and MxD groups were impaired on this task. High-fat diet generally impaired spatial memory in the Morris water maze across mouse models, with females again being more adversely affected by diet, and MxD (regardless of diet) also hindered performance. These findings confirm our hypothesis that females are more susceptible to the effects of chronic high-fat diet (prediabetes) in models of AD and MxD.
Do Older Men and Women Show Differential Patterns of Tau Pathology Across the Brain?
Rachel Buckley1,2,3, Matthew Scott1, Heidi Jacobs1,2, Aaron Schultz1,2,3, Michael Properzi1, Elizabeth Mormino4, Jasmeer Chhatwal1,2, Keith Johnson1,2,3, and Reisa Sperling1,2,3
1Massachusetts General Hospital, Boston, MA,USA
2Harvard Medical School, Boston, MA, USA
3Brigham and Women’s Hospital, Boston, MA, USA
4Stanford University, Stanford, CA, USA
Clinically-normal women with elevated amyloid burden have been found to exhibit higher tau in the entorhinal cortex relative to men. It remains unclear, however, whether women consistently show elevated tau across the entire cortex or whether topographical distributions of tau can be differentiated by sex. We hypothesized that women, particularly female apolipoprotein ∊4 (APOE∊4) carriers, would show elevated tau in AD-vulnerable regions of the temporal lobe relative to men. Our analyses used 337 clinically-normal (CN) older adults from the Harvard Aging Brain Study (HABS; n = 236) and ADNI (n = 101). Tau signal was examined in 43 bihemispheric regions of interest (ROIs) with partial-volume corrected 18F-Fluortaucipir-PET. Linear regression models were used to examine sex differences in each ROI, adjusting for APOE∊4, age, and cohort. Separate models also examined the interaction of APOE∊4*sex on each ROI. Women had significantly greater tau signal in 7 ROIs than men. These regions were the lateral occipital, inferior parietal, superior parietal, rostral middle frontal, fusiform, supramarginal, and middle temporal regions; Figure 3). Average percent differences (women > men) were 5.9%, 5.1%, 4.2%, 4.1%, 2.8%, 2.2%, and 2.1%, respectively. Female APOE∊4 carriers exhibited higher tau signal in the lateral occipital, entorhinal, and hippocampal regions; however, these findings did not survive Bonferroni correction. In conclusion, tau pathology may manifest as a regional pattern of female susceptibility not limited to AD-related regions. As such, tau deposition may be motivated, to some degree, by sex-associated mechanisms. The small effect sizes, however, suggest that sex-related risk exists within a milieu of other factors, rather than representing a predominant pathway for tau deposition. Further investigation is required to determine whether these findings are motivated by biological or environmental factors.
Brain map of F > M differences (scale indicates the bstd).
Hormonal Regulation of Risky Decision Making in Male and Female Rats
Caitlin A. Orsini, PhD1, Shelby L. Blaes, BS1, Jennifer L. Bizon, PhD1,2,3, and Barry Setlow, PhD1,2,3,4
1Department of Psychiatry, University of Florida College of Medicine, Gainesville, FL, USA
2Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL, USA
3Center for Addiction Research and Education, University of Florida, Gainesville, FL, USA
4Department of Psychology, University of Florida, Gainesville, FL, USA
Chronic substance abuse is associated with maladaptive decision-making and elevated risk-taking behavior. A potential treatment for substance use disorders (SUDs) could therefore be to attenuate such maladaptive choice behavior so as to mitigate drug-seeking and potential relapse. Progress toward achieving this goal is constrained, however, by our limited knowledge regarding sex differences in risk taking. A wealth of evidence has shown that males and females differ considerably in the propensity for and manifestation of SUDs. Nevertheless, to date, the majority of the work investigating the relationship between risk taking and substance use has been conducted in males. It is therefore prudent to determine whether interactions between substance use and risk taking differ between males and females. As a first step toward addressing this question, we have shown that females are more risk averse than males in a rat model of risky decision-making. We hypothesized that these sex differences were due to differences in hormonal modulation of risk taking. To test this, males and females rats were trained in a risky decision-making task in which rats chose between a small, “safe” food reward and a large, “risky” food reward accompanied by varying probabilities of mild footshock. Subsequently, half of the females were ovariectomized (OVX) and half of the males were castrated and were then retested. There were no differences between CAST and sham male rats; however, there was an increase in risky choice in OVX rats relative to sham females. Others have shown that testosterone (T) administration can modulate risk taking in intact male rats and estradiol (E) can mitigate effects of OVX on decision-making behavior. Hence, 2 months after surgery, the effects of acute T injections on risk taking were assessed in male CAST and sham rats and the effects of acute E injections on risk taking were assessed in female OVX and sham rats. There were no effects of T on risk taking in either CAST or sham rats. While acute E did not alter risk taking in OVX rats, the highest dose of E increased risky choice in sham females. To determine if effects of E in OVX rats depended on the duration of hormone deprivation, separate OVX and sham females received E 3 weeks after OVX. At this time point, there were no effects of acute E on risk taking in either OVX or sham females. Finally, E (0, 10, 20 µg/0.1 mL) was administered using a subchronic regimen (7 days) during which time risk taking was monitored in OVX and sham females. While there were no effects of subchronic E on risk taking in shams, the highest dose of E significantly decreased risk taking in OVX females. Collectively, these data show that T is not essential for maintaining risk taking in males, but circulating levels of E are necessary for archetypal risk aversion in females. Future directions will extend this work by determining the relationships between risk taking and drug-seeking behavior in females and whether such relationships are similarly modulated by ovarian hormones.
Ally Skills: How to Stand Up and Step In
Sherry A. Marts1
1S*Marts Consulting LLC
Have you ever found yourself on the receiving end of a “compliment” that felt like an insult? Have you brought up ideas in meetings that were ignored, only to be received with enthusiasm when someone else presented them? Have you ever felt like you had to hide some aspect of your life or your personality in order to fit in at work? You need allies. Have you ever watched these things happen to someone else, and wished you knew what you could do intervene without making things worse? You can be an ally. Ally skills are a combination of self-education, awareness, and learned approaches to addressing implicit bias, microaggressions, and other behaviors that get in the way of full inclusion in diverse groups. Ally skills are what you need to be able to stand up and stand beside those who experience slights, insults, and microaggressions on a daily basis. This Ally skills session will help raise your awareness of all the subtle ways that bias shows up, and will give you options for how to take action, stand up, and step in.
Impact of Sex on Metabolic Contributions to Dementia—Introduction
Kristen L. Zuloaga1
1Department of Neuroscience & Experimental Therapeutics, Albany Medical College, Albany, NY, USA
Diabetes is a well-known risk factor for both vascular dementia and Alzheimer disease, yet sex differences in metabolic contributions to dementia are poorly understood. The session will cover the latest research on effects of sex and endocrine aging on metabolic and vascular contributions to dementia. Specifically, Dr Brinton will present compelling evidence that postmenopausal females have a decrease in brain glucose utilization that causes them to use their white matter for fuel. Dr Robison and Dr O’Connell will present evidence that there are sex differences in the effect of prediabetes/high-fat diet in different mouse models of Alzheimer’s disease and how these sex differences can be influenced by vascular injury, genetic diversity, and disease severity. Finally, Dr Ergul will describe sex differences in how diabetes alters neurovascular communication.
Sex Differences in Anterior Cruciate Ligament Injury
Nathan D. Schilaty1, and Timothy E. Hewett1
1Mayo Clinic, Jacksonville, FL, USA
Anterior cruciate ligament (ACL) injuries largely occur by a noncontact mechanism (76%), meaning that the individual only comes into contact with the ground. Thus, these injuries are likely preventable! However, these injuries entail long rehabilitation and are associated with long-term detrimental sequelae of early-onset osteoarthritis, high risk for second injury, and lowered activity levels. In addition, females are 2 to 6 times at increased risk for an ACL injury than male counterparts. The hypothesis is that ACL injuries can be reduced by application of neuromuscular interventions that improve proprioception and sensorimotor control, especially for females. Proprioception, although important to injury prevention, has been difficult to measure. The current research explores various tools (ie, shear wave ultrasound, high-speed perturbation, and perceived effort) to measure proprioception. These measures may provide an avenue to both measure and improve neuromuscular interventions for ACL injury reduction.
Ethobehavioral Studies of Sexually Dimorphic Risky Decision Making in Rats
Jeansok J. Kim1
1University of Washington
The scientific understanding of fear and anxiety is presently limited by a predominance of studies that use male animals only and Pavlovian fear conditioning paradigms that cannot simulate the dynamic range of risky situations in nature that require various adaptive actions and decisions. I will present data from naturalistic “closed economy” and “approach food-avoid predator” fear paradigms in rats, in which the need to acquire food/water and the need to avoid threats are simultaneously integrated into the lives of animals. Specifically, we find that male rats make significantly more risky foraging decisions than female rats and that the sex differences in risk mitigation strategies are not due to the activational effects of gonadal hormones but, rather, are likely to be organized during early development.
Peptidergic Influences on Sex Differences in Cognitive Functions
Laura A. Grafe1 and Seema Bhatnagar1
1Stress Neurobiology Program, Children’s Hospital of Philadelphia, PA, USA
2University of Pennsylvania School of Medicine, Philadelphia, PA, USA
Women are twice as likely as men to suffer from stress-related psychiatric disorders, such as post-traumatic stress disorder (PTSD) and major depressive disorder (MDD); however, the biological basis of these sex differences is not fully understood. Interestingly, orexins are known to be dysregulated in these disorders and are known to play a role in many of the phenotypes associated with stress-related mental illness such as changes in cognition, sleep-wake states, and appetite. We recently found that female rats have increased orexin expression and activation compared with males, leading to impaired habituation to repeated stress and subsequent cognitive deficits. We extended our study of sex differences in the role of orexins to examining morphology of putative orexin neurons and spine densities in orexin neurons and whether these differ between male and female rats both in nonstress conditions as well as after 5 consecutive days of 30-minutes restraint stress. Dendritic complexity did not differ between nonstressed males and females, however repeated stress decreased total dendritic length, branching, and nodes primarily in males. Thus, repeated stress reduced dendritic complexity of putative orexinergic neurons in males but not in females. This might be reflective of decreased orexin system function after repeated restraint in males, which allows males to habituate more fully to repeated restraint than females. Analysis of spine distribution and density indicated that putative orexinergic neurons in control females had significantly more dendritic spines than those in control males, and the majority of these were mushroom spines. Finally, stress reduced spine densities in females but not in males. Again, these were primarily the mature, mushroom spines. Together, these findings extend our understanding of sex differences in orexins and suggest that morphological characteristics of orexin neurons may be less adaptive to repeated stress in females. Current studies are examining the role of orexins in stress-related changes in sleep in male and female rats.
Vascular Cognitive Impairment in Diabetes: Lost Communication Within the Neurovascular Unit
Diabetes increases the risk and severity of cerebrovascular complications such as vascular dementia (VCI), stroke, and post-stroke cognitive impairment (PSCI), contributing to greater physical and cognitive disability in this high-risk population. It is also known that women suffer more from unfavorable stroke outcomes and PSCI, necessitating long-term nursing care. The failure of all neuroprotection research led to the realization that cerebral microvasculature is a key component of a reparative and restorative microenvironment required for effective neurorestorative strategies to promote functional recovery. Our studies with male diabetic animals showed that (a) diabetes promotes pathological neovascularization of the brain, (b) stroke superimposed on this pathology amplifies bleeding into the brain and worsens neurological deficits without increasing infarct size, and (c) toll like receptor TLR4, a major mediator of innate inflammatory response, is upregulated in the ischemic region and especially in cerebral microvasculature. While testing the hypotheses excess iron attenuates neurovascular restoration via the activation of TLR-4 leading to cognitive impairment, initial studies with female animals untraveled sex differences. We observed that (1) young diabetic female rats lose the neuroprotection typically seen in control female animals and develop greater bleeding than controls and even diabetic male rats; (2) matrix metalloprotease (MMP)-3, an enzyme known to cause bleeding and to be regulated by TLR4, is increased to a greater degree in cerebral microvessels of female diabetic rats; (3) while male diabetic animals show significant loss of cerebrovasculature by activation of multiple cell death pathways in the recovery period, female diabetic animals do not, but rather undergo phenotypic changes in endothelial cells resembling endothelial-mesenchymal transition, EndMT, a process associated with scarring and impaired healing, and (4) in the long-term, diabetes worsens sensorimotor and cognitive recovery in both sexes. We aim to provide an overview of our current knowledge of the impact of diabetes on cerebrovascularization in both sexes with a focus on vascular contributions to cognitive impairment and dementia (VCID) spectrum of diseases which include PSCI and VCI.
Sex-Differential Expression of the Equilibrative Nucleoside Transporter 1 in Placental Tissue
Julian Gilmore1, Lena Serghides1, and Reina Bendayan1
1University of Toronto, Toronto, Ontario, Canada
Combination antiretroviral (ARV) therapy during pregnancy is increasingly effective in reducing risk of vertical human immunodeficiency virus (HIV) transmission, however the fetal toxicity of widely administered ARV drugs remains poorly described and existing literature often does not account for sex as a variable. New evidence of sex-linked toxicities in ARV drug exposed children suggests differential drug disposition between male and female subjects, which may be explained by variable expression of drug transporters of the ATP binding cassette (ABC) and solute carrier (SLC) super-families. These transporters have been implicated in the distribution of ARV drugs across the placenta, and play an important role in fetal drug disposition. This research aims to investigate the expression of ARV drug transporters in fetal tissues primarily by quantitative PCR and immunoblotting. Preliminary data has confirmed the expression of a panel of ARV drug transporters in the mouse placenta at the mRNA and protein level, demonstrating the high relative mRNA expression of Abcb1b, Abcg2, and Slc29a1. Further investigation into the expression of these genes revealed significantly higher expression of Slc29a1 mRNA—coding for the equilibrative nucleoside transporter 1—in placenta associated with female compared to male fetuses. This early data provides novel evidence of sex-differential expression of multidrug transporters in fetal tissues, suggesting a differential penetration of ARV drugs into the fetus. Ongoing research into other fetal tissues including the brain, will help in understanding the underlying causes of sex-differential outcomes in ARV drug exposed children leading to safer and more effective HIV treatment during pregnancy.
Sex Differences in Clinical Treatment of Opioid Use Disorder
R. Kathryn McHugh1 and Shelly F. Greenfield1
1Harvard Medical School & McLean Hospital
Approximately 5.1 million women in the United States misused opioids in 2017 and 900 000 women met criteria for an opioid use disorder. In the past 2 decades, the rate of opioid overdose deaths has grown more quickly among women relative men, with over 15 000 women dying of opioid overdose in 2017. However, women continue to be underrepresented in research on opioid use disorder, and much remains to be understood about sex differences in the treatment of this condition. In this presentation, we will provide an overview of sex differences in the treatment of opioid use disorder and will highlight essential future directions for research on women with opioid use disorder. Studies of treatment for opioid use disorder have not found substantive differences in substance use outcomes between men and women, suggesting that both sexes respond to evidence-based treatments, such as buprenorphine and naltrexone. However, there are a number of significant differences between men and women with opioid use disorder that have implications for treatment. Women seeking treatment for opioid use disorder are more likely to have cooccurring psychiatric illnesses, are more likely to use opioids to cope, and experience greater functional impairment than men. Women also face more barriers to treatment entry, including access to naloxone during an overdose event. Furthermore, perinatal opioid use and related consequences (eg, neonatal opioid withdrawal syndrome) have risen drastically in the last 2 decades. The combination of opioid agonist therapy, prenatal care, and other ancillary supports is effective for the improvement of both maternal and neonatal health outcomes. Further research is needed to improve understanding of treatment for women with opioid use disorder, particularly related to optimal treatment strategies for issues that disproportionately affect women, such as cooccurring psychiatric disorders and the couse of benzodiazepines.
Adverse Drug Reactions to Guideline-Recommended Heart Failure Drugs in Women: A Systematic Review of the Literature
Sophie H. Bots1, Floor Groepenhoff2, Anouk L. M. Eikendal1, Cara Tannenbaum3, Paula A. Rochon4,5, Vera Regitz-Zagrosek6,7, Virginia M. Miller8, Danielle Day9, Folkert W. Asselbergs10,11,12,13, and Hester M. den Ruijter1
1Laboratory of Experimental Cardiology, University Medical Center Utrecht
2Laboratory of Clinical Chemistry and Haematology, University Medical Center Utrecht
3Faculties of Pharmacy and Medicine, Université de Montréal, Montréal, Quebec, Canada
4Women’s College Research Institute, Women’s College Hospital
5Dalla Lana School for Public Health, University of Toronto, Toronto, Ontario, Canada
6Institute for Gender in Medicine and Center for Cardiovascular Research, Charite, University Medicine Berlin
7DZHK (German Center Cardiovascular Research), Partner Site Berlin
8Women’s Health Research Center, Mayo Clinic, Jacksonville, FL, USA
9UniQure, Amsterdam, the Netherlands
10Department of Cardiology, University Medical Center Utrecht
11Institute of Cardiovascular Science, Faculty of Popular Health Science, University College London
12Health Data Research UK
13Institute of Health Informatics, University College London
Women are more likely to experience ADRs than men, which may negatively affect their immediate and long-term health. HF in particular is associated with increased ADR risk due to the high number of comorbidities and older age. However, little is known about ADRs in female HF populations treated with guideline-recommended drugs. We aimed to summarise all available evidence on sex differences in adverse drug reactions (ADRs) to heart failure (HF) medication. We performed a systematic search in PubMed and EMBASE to collect all available information on ADRs to angiotensin-converting enzyme inhibitors (ACEIs), β-blockers, angiotensin II receptor blockers (ARBs), mineralocorticoid receptor antagonists (MRAs), ivabradine, and digoxin in both women and men with HF. The search identified 155 eligible records, of which only 11 (7%) reported ADR data for women and men separately. Sex-stratified reporting of ADRs did not increase over the last decades. Six of the 11 studies did not report sex differences. Three studies reported a higher risk of ACEI-related ADRs in women, 1 study showed higher digoxin-related mortality risk for women, and 1 study reported a higher risk of MRA-related ADRs in men. No sex differences in ADRs were reported for ARBs and β-blockers. Sex-stratified data were not available for ivabradine. These results underline the scarcity of ADR data stratified by sex. We call for a change in standard scientific practice toward reporting of ADR data for women and men separately.
Exploring Sex Differences and the Impact of Testosterone on Hippocampal and Amygdala Volumes in Schizophrenia
Claudia Barth1, Kjetil N. Jørgensen2, Ole A. Andreassen1, and Ingrid Agartz3
1Norwegian Centre for Mental Disorders Research, University of Oslo, Norway
2Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway
3Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
Men have a 40% higher likelihood of developing schizophrenia than women, for reasons not fully known. Emerging evidence suggests exposure to testosterone might confer risk for illness onset. Brain structures which seem most sensitive to testosterone are implicated in the pathophysiology of schizophrenia, such as the hippocampus and amygdala. Here, we aim to explore sex differences in hippocampal and amygdala volumes in healthy controls and schizophrenia patients, and whether these are driven by testosterone. As previous studies proposed decreased testosterone levels in male patients, we expect diminished sex differences in these regions relative to controls. A sample of 109 controls (31.9 ± 7.97 years, 41 females) and 178 patients (30.54 ± 8.59 years, 61 females) were drawn from the ongoing Thematically Organized Psychosis study, Oslo. Participants underwent T1-weighted structural imaging at 1.5 T (n = 134) and at 3 T (n = 153). Brain images were processed to obtain volumes of bilateral hippocampus and amygdala, as well as intracranial volume (ICV), using Freesurfer (version 5.3). Multiple linear regression models were calculated to predict volumes based on group status and sex (with interaction term) and fasting testosterone levels, while accounting for age, age2, ICV and scanner, using R (version 3.5.2). We found a significant interaction between group status and sex for the hippocampus (t = −2.6, P = .009), but not for the amygdala (t = −1.0, P = .32). Patients showed decreased hippocampal volume relative to controls, most prominently in males. For both sexes, testosterone levels neither differed significantly between patients and controls nor showed association with the volumes under study. These findings indicate diminished sex differences in hippocampal but not amygdala volume in patients with schizophrenia, partly in accordance with our hypothesis. However, the notion that these differences might be driven by testosterone levels was not supported.
A Sex-Specific Role for PICK1 in the Prefrontal Cortex During Cocaine Seeking
Megan M. Wickens1, Julia M. Kirkland1, Lisa A. Briand1,2
1Department of Psychology, Temple University, Philadelphia, PA, USA
2Neuroscience Program, Temple University, Philadelphia, PA, USA
Protein interacting with C-Kinase 1 (PICK1) is a postsynaptic scaffolding protein that regulates glutamate receptor trafficking. Protein interacting with C-Kinase 1 binds to GluA2 AMPA subunits leading to the subsequent internalization of AMPA receptors. Global knockout of PICK1 and local infusion of PICK1 inhibitors into the nucleus accumbens dampen cocaine taking and seeking. However, nothing is known about the role of PICK1 in the prefrontal cortex. As glutamate receptor trafficking within the prefrontal cortex (PFC) is altered by cocaine administration, examining the role of proteins involved in trafficking could shed light on the mechanisms underlying addictive phenotypes. The current study examined how site-specific knockdown of PICK1 in the PFC affects food and cocaine taking and seeking in both male and female mice. Prefrontal knockdown of PICK1 did not affect food self-administration or the acquisition of an operant response in either male or female mice. Additionally, no differences in cocaine intake or responding were seen following PFC knockdown of PICK1 during the self-administration phase. However, when we examine cocaine seeking during a cue-induced reinstatement session, we find that male mice with a PFC-specific PICK1 knockdown exhibit a decrease in cocaine seeking compared to GFP-injected control male mice. In contrast, female mice exhibit an increase in cue-induced cocaine seeking following prefrontal knockdown of PICK1. These results suggest that PICK1 in the prefrontal cortex is playing opposing roles in cocaine seeking in male and female mice. This suggests that the synaptic mechanisms underlying substance use disorder could be distinct in males and females and sex-specific treatments may be needed.
Sex-Specific Associations Between Gestational Di (2-ethylhexyl) Phthalate Exposure and Maternal Steroid Hormones—Modification by Maternal Obesity
Diana C. Pacyga1, Susan L. Schantz2,3, and Rita S. Strakovsky1
1Michigan State University
2University of Illinois
3Urbana-Champaign
Diet is a ubiquitous source of di (2-ethylhexyl) phthalate (DEHP), and almost all US pregnant women have measurable urinary levels of its metabolites. Di (2-ethylhexyl) phthalate is an endocrine disrupting chemical with sex-specific effects on fetal and pregnancy outcomes, including maternal hormones. We have observed that maternal obesity also disrupts maternal hormones in a fetal sex-specific manner. Therefore, we assessed whether sex-specific associations of DEHP with maternal estrogen and testosterone differed based on maternal obesity status. In 291 pregnant Illinois women, 4 urinary DEHP metabolites were assessed in a pooled sample of 5 urines collected across pregnancy (ΣDEHP) and summed. Urinary testosterone (T) and 8 urinary estrogens/metabolites were measured by LC/MS/MS at 10-14, 28-30, and 34 to 36 weeks gestation, and the 8 estrogens were summed (ΣE). Women reported their prepregnancy body mass index (ppBMI) and lifestyle/demographic factors at 10 to 14 weeks gestation. Linear mixed models assessed associations of ln-ΣDEHP with ln-T and ln-ΣE across pregnancy, controlling for potential confounders. Modifications by fetal sex and maternal ppBMI were also explored. Women were predominantly white, college educated, married, middle-class, and 49% had a normal ppBMI (<25 kg/m2). Urinary DEHP metabolite levels were similar to reported levels in US women. Urinary ΣDEHP was not associated with testosterone. However, every 1.0% increase in ΣDEHP was associated with 0.7% higher maternal ΣE across pregnancy, but only in women carrying a female fetus (95% CI: 0.1-1.2). In these women, the association was further modified by ppBMI; a 1.0% increase in ΣDEHP was associated with 1.0% higher ΣE (95% CI: 0.18-1.88) only in women who were not obese (ppBMI < 30 kg/m2). These findings suggest that DEHP has sex-specific effects on maternal ΣE, but not in obese women, who already have disrupted ΣE levels. Additional studies are needed to understand the impact of these results on fetal outcomes.
Sex Differences in Hippocampal Neurogenesis in a Mouse Model of Diet-Induced Obesity
Abigail Salinero1, Lisa Robison1, and Nathan Albert2, Lauren Camargo1, and Kristen Zuloaga1
1Albany Medical College
2Rensselaer Polytechnic Institute
Type 2 diabetes suppresses hippocampal neurogenesis, a form of brain plasticity associated with learning and memory. This may have significant implications regarding the association between type 2 diabetes and risk of dementia, for which there is a sex difference, with women being at increased risk relative to men. Even in the absence of overt diabetes, obesity and metabolic syndrome are associated with decreased cognitive function and increased dementia risk. Despite the difference in this risk, sex differences in the effect of a high-fat diet on hippocampal neurogenesis have yet to be thoroughly investigated. We hypothesized that diet induced obesity (DIO) females would suffer a greater suppression of neurogenesis, relative to males. Male and female C57BL/6J mice were put on either a high fat or low fat (control) diet for 3 months. Body weight was tracked throughout the dietary intervention. After 3 months on the diet, mice underwent a glucose tolerance test to assess diabetic status, and were injected with EdU, an exogenous marker of cell proliferation. Mice were killed 1 week or 1 month later. To examine cell proliferation, maturation, and survival, brains were stained for EdU,as well as Ki67, doublecortin (DCX), and NeuN. Our data show that a high-fat diet decreased hippocampal neurogenesis to a greater extent in females than in males. Further, both weight gain and glucose tolerance negatively correlated with DCX+ neuroblasts in females but not males. This supports the need for sex-specific strategies in treating the neuronal effects of metabolic disease.
Determining the Differential Mechanisms by Which Histone Demethylases JARID1c and JARID1d Regulate Male and Female Dendritic Cell Function During Quiescence and Activation
Mario Corrado1 and Connie M. Krawczyk1,2
1McGill University, Montreal, Quebec, Canada
2Van Andel Research Institute
Increasing evidence suggests sexual dimorphism in immune response; females mount a more potent response than males. An over-activated immune system can bypass self-tolerance mechanisms and promote autoimmune pathologies. Indeed, 80% of autoimmune patients are female. However, the molecular mechanisms that account for sex-specific immune response remain poorly understood. Dendritic cells (DCs) are crucial for controlling immune responses; upon stimulus recognition, the DCs transition from an actively restrained “steady state” to an activated state capable of instructing antigen-specific adaptive immune responses. Although much is known about the molecules that promote DC activation, the mechanisms involved in actively maintaining the steady state remain poorly understood. Our lab has identified an epigenetic axis in DC activation, whereby the transcriptional repressors PCGF6 and JARID1c restrain DC activation by altering the DC epigenome at key loci. JARID1c is an X-linked H3K4 histone demethylase that escapes X-inactivation; females express 2 copies of Jarid1c, whereas males express one copy of its Y-linked paralogue Jarid1d. Here, we hypothesize that sex-specific differences in DC function are regulated epigenetically by JARID1c and JARID1d. Using bone marrow-derived dendritic cells (BMDCs) from C57BL/6 age-matched mice as an in vitro model, we found important phenotypic differences between male- and female-derived BMDCs in response to LPS stimulation. We also found sex-disparate regulation of Jarid1c and Jarid1d in LPS-activated BMDCs. In vivo characterization of several DC subtypes from wild-type and Jarid1cfl/fl-Cre mice also revealed important immunophenotypic differences within several immune tissues. Together, our study investigates sex-biased immune response and provides evidence to support epigenetic regulation by JARID1c/d as a factor implicated in sexually dimorphic immunity, which is of great relevance to Canadian healthcare.
Pre-Menopausal Women With Palpitations Have More Symptom, Anxiety, Depression, and Lower HRQOL Than Post-Menopausal Women
Carina I. Carnlöf1, Per W. Insulander1, Mats Jensen-Urstad1, Karin Schenck-Gustafsson2
1Karolinska Institute, Institution of Medicine, Huddinge, Stockholm, Sweden
2Karolinska Institute, Institution of Medicine, Solna, Stockholm, Sweden
Palpitation is common, particularly in women, and usually benign caused by premature atrial/ventricular beats or stress-induced sinus tachycardia. Palpitations may cause disturbing symptoms, anxiety, depression, and decreased health-related quality of life (HRQOL). Uncommonly, arrhythmias of clinical importance such as atrial fibrillation, paroxysmal supraventricular, or ventricular tachycardia may be the cause. The aim of this study was to evaluate if instant analysis of underlying heart rhythm during palpitations reduces symptoms, anxiety, depression, and increase HRQOL and if there is a difference between pre- and postmenopausal women. In all, 913 women (338 ≤ 52 and 557 ≥53 years old [in average 44 ± 7 vs 63 ± 7]) with palpitations were recruited from social web sites. Coala Heart Monitor was used by the participants and ECG was recorded twice a day and at symptoms for 60 days. The system uses a well-validated algorithm to analyze heart rhythm is connected to the user’s smartphone and provides immediate response to the user. Questionnaires addressing symptom (Symptom severity and frequency checklist [SCL], anxiety, depression Hospital anxiety and depression scale [HADS], Generalized Anxiety Disorder [GAD-7], and HRQOL [RAND-36]) were analyzed before and after 2 months. Exclusion criterium was known atrial fibrillation. Premenopausal women scored higher than postmenopausal women in both scales of the SCL, P < .001, higher in total anxiety and depression score measured by HADS and GAD-7, <0.001 and lower in 5 components in RAND-36. After 60 days with the heart monitor, the younger women were still more symptomatic, improved less in HRQOL, where more depressed, and had more anxiety. We concluded that instant analysis of the ECG with direct response to the user during palpitations reduce symptoms, anxiety, depression, and increase HRQOL but more so in post- than pre-menopausal women.
Sex-Specific Probiotic Disruption of Pubertal LPS-Induced Inflammatory Responses
Emma Murray1, Atiqa Pirwani1, Sanjeevani Lamba2, and Nafissa Ismail1
1Neuroimmunology, Stress and Endocrinology (NISE) Lab, University of Ottawa, Ottawa, Ontario, Canada
2School of Biosciences, Cardiff University, Cardiff, Wales, United Kingdom
The gut microbiome is a biological system that can regulate stress and systemic immune responses, and can alter brain chemistry and behaviour. Puberty is a critical period in development that is vulnerable to stress and immune challenges. Exposure to an immune challenge (lipopolysaccharide; LPS) during puberty in mice causes enduring effects on anxiety- and depression-like behaviour and future response to stress. The mechanisms influencing this effect remain poorly understood. The current study investigated the sex-specific responses to probiotic treatment during puberty on LPS-induced sickness, pro- and anti-inflammatory peripheral cytokine responses and central mRNA cytokine expression at 8 hours post IP injection. Eighty CD1 male and female mice were treated with probiotics (kefir or milk control) for 1 week and exposed an immune challenge (LPS or saline control) at 6 weeks of age. Lipopolysaccharide treatment induced sickness and inflammation in all mice. Males showed more sickness behaviour compared to females and a higher blood plasma cytokine concentration. Kefir reduced concentrations of TNFα, IL-10, and IL-12 in LPS-treated males compared to milk control counterparts. In contrast, females displayed a more robust LPS-induced central inflammatory response compared to males. These sex differences were less significant with probiotic treatment. Probiotic treatment reduced sickness behaviour in females, in a time-specific manner, and reduced TNFα and IL-6 mRNA expression, in a region-specific manner. Lipopolysaccharide-treated males showed significant increases in IL-6 and TNFα mRNA expression in both the hypothalamus and hippocampus. Yet, with probiotic treatment, treatment differences between LPS and saline-treated males were eliminated. Our findings clarify pubertal sex-specific immune response and mediating properties of gut microbes. Findings suggest probiotics have protective effects during puberty, which may prevent lasting negative neurochemical and behaviour consequences.
Global Reporting of Adverse Drug Reactions in Men and Women
Sarah Watson1, Paula Rochon2,3, and Hester den Ruijter4
1Uppsala Monitoring Centre, Uppsala, Sweden
2Department of Medicine and Institute of Health Policy, Management & Evaluation, University of Toronto, Canada
3Women’s College Research Institute, Women’s College Hospital Ola Caster, Uppsala Monitoring Centre, Uppsala, Sweden
4Laboratory of Experimental Cardiology, University Medical Center Utrecht, University of Utrecht, Utrecht, the Netherlands
References
1. Kando JC, Yonkers KA, Cole JO. Gender as a risk factor for adverse events to medications. Drugs. 1995;50(1):1-6.
2. Franconi F, Brunelleschi S, Steardo L, Cuomo V. Gender differences in drug responses. Pharmacol Res. 2007;55(2):8195.
3. Holm L, Ekman E, Jorsater Blomgren K. Influence of age, sex and seriousness on reporting of adverse drug reactions in Sweden. Pharmacoepidemiol Drug Saf. 2017;26(3):335-343.
4. Martin RM, Biswas PN, Freemantle SN, Pearce GL, Mann RD. Age and sex distribution of suspected adverse drug reactions to newly marketed drugs in general practice in England: analysis of 48 cohort studies. Br J Clin Pharmacol. 1998;46(5):505-511.
Single Cell Profiling of the VMH Reveals a Female-Specific Regulatory Node of Energy Expenditure
J. Edward van Veen1, Laura G. Kammel1, Patricia C. Bunda1, Michael Shum2, Michelle S. Reid1, Jae W. Park1, Zhi Zhang1, Megan G. Massa, Douglas Arneson1, Haley Hrncir1, Marc Liesa2, Arthur P. Arnold1, Xia Yang1, and Stephanie M. Correa1
1UCLA, Los Angeles, CA, USA
2David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
Estrogen signaling in the central nervous system promotes weight loss by increasing thermogenesis and physical activity. Changes in these 2 facets of energy expenditure are mediated by ERa-expressing neurons in the ventromedial hypothalamus (VMH) of female but not male mice. We hypothesize that these distinct and sex-specific functions are mediated by nonoverlapping subpopulations of ERa+ neurons. Here, we define the molecular and functional heterogeneity of the VMH using single cell RNA sequencing, in situ hybridization, chemogenetic activation, and targeted gene knockdown. We describe 6 molecularly distinct neuron clusters in the VMH. In females, estrogen receptor alpha (ERa) is restricted to neurons expressing tachykinin-1 (Tac1) or reprimo (Rprm). Further, Tac1 and Rprm expression is enriched in females, a sex difference that is established by permanent effects of gonadal hormones early in life. Finally, while Tac1 ablation selectively impairs movement, here we show that silencing Rprm selectively dysregulates temperature without affecting physical activity. Together this work provides a novel architectural framework whereby distinct and sexually differentiated neuron populations within the VMH mediate sex-specific aspects of metabolic homeostasis.
Sex Specific Effects of Nicotine and Oral Contraceptives on the Rat Brain Energy Metabolism
Francisca Diaz1 and Ami P. Raval1
1Cerebral Vascular Disease Research Laboratories, University of Miami, Miami, FL, USA
Smoking-derived nicotine (N) and oral contraceptives (OC) are known to synergistically magnify the risk and severity of cerebral ischemia in females. The underlying pathological mechanism remains elusive. Our studies have shown that N toxicity is exacerbated by OC via altered mitochondrial function, which involved a defect in activity of cytochrome c oxidase, the terminal enzyme of the electron transport chain. However, the effects of impaired mitochondrial function on brain metabolism remain to be investigated. To understand the impact in brain metabolisms, in the current study we investigated the global metabolomic profile of brains of adolescent and adult female rats exposed to N +/− OC. Six and 12 weeks old Sprague-Dawley female rats were randomly (n = 8/group) exposed to either saline, N (4.5 mg/kg) +/− OC for 16 to 21 days. At the end of the treatment, brain tissue was harvested for metabolomic analysis (performed by Metabolon Inc.) The metabolomic profile was complemented with Western blot analysis and enzyme activity measurements. Pathway enrichment analysis showed significant changes in energy metabolism (glycolysis and TCA cycle) and neurotransmitters in both adolescent and adult rats exposed to N, OC, and N + OC in relation to saline treatment. The changes were more pronounced in adolescent rats with a significant decrease in glucose, glucose 6-phosphate, fructose-6-phosphate along with a significant increase in pyruvate in N and N+OC exposed groups when compared to saline (P < .05), suggesting alterations in the glycolytic pathway. Western blot analyses of glycolytic enzymes support the observed metabolic changes. Nicotine and N + OC exposure increased brain glycolysis in an age-dependent manner. Since glucose metabolism is critical for brain physiology, altered glycolysis deteriorates neural function thus exacerbating ischemic brain damage. Moreover, significant decrease in the neuroactive peptide GABA was observed in young female rats treated with N+OC when compared to saline group. Discerning the exact effects of N +/− OC on overall brain metabolism and the molecular mechanisms affecting mitochondrial function at different ages will open a new window for future therapeutic intervention.
Sex and Hormone Differences in Strategy Use Following Spatial Learning
Liisa A. M. Galea1 and Shunya Yagi1
1University of British Columbia, Vancouver, British Columbia, Canada
Men and women differ in severity of cognitive disruptions and neural manifestations of the neurodegenerative disease. For example, women are more likely to exhibit greater cognitive deterioration with AD compared to men. The hippocampus produces new neurons throughout the life span in rodents and humans and adult neurogenesis plays a crucial role for pattern separation and for spatial long-term memory. However, it is important to establish how neurogenesis in the hippocampus may be involved in hippocampus-dependent cognition in both males and females given the sex differences in cognitive disruptions following diseases that impact the hippocampus. Work in my laboratory has shown that there are sex differences, favoring males, in strategy use following pattern separation and ovarian hormones influence strategy use in pattern separation and following spatial or cued training in the water maze. Male spatial strategy users outperformed female spatial strategy users only when separating similar, but not distinct, patterns. However, there were no sex differences in strategy use in a cued-competition task. Furthermore, male spatial strategy users had greater neurogenesis in response to pattern separation training than all other groups consistent with findings in the Morris Water Maze showing that spatial training increased neurogenesis in males but not in females. Consistent with past research, ovarian hormones influenced spatial strategy use in females. Estradiol also influence the ability of neurogenesis to be upregulated in the hippocampus after pattern separation dependent on strategy use. In these different tasks, data is emerging to suggest that the CA3 region is particularly active in females compared to males. We also have preliminary evidence that the maturation timeline of new neurons may be different between the sexes that could contribute to findings that males show an enhancement but not females after learning. These findings emphasize the importance of studying biological sex on hippocampal function and neural plasticity and have implications for neurodegenerative disorders that target the hippocampus and affect cognition differentially in women versus men.
17β-Estradiol Affects Lung Function and Inflammation Following Ozone Exposure in a Sex-Dependent Manner
Nathalie Fuentes1, Marvin Nicoleau1, Noe Cabello1, and Patricia Silveyra1,2
1Penn State College of Medicine, Hershey, PA, USA
2University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
Ozone exposure contributes to impairment of lung innate immunity. Emerging evidence suggests that lung diseases affect men and women disproportionately, and that fluctuations of circulating hormone levels can affect inflammatory responses. Here, we hypothesized that 17β-estradiol regulates inflammation and airway hyperresponsiveness (AHR) triggered by ozone exposure. We performed gonadectomy and hormone replacement (17β-estradiol, 2 weeks) in C57BL/6J male and female mice, and exposed animals to 1 ppm of ozone or filtered air for 3 hours. We compared lung function parameters, expression of cytokines/chemokines in lung tissue, and lipocalin-2 levels in bronchoalveolar lavage fluid (BALF). We found significant changes in respiratory parameters and gene expression in males and females after ozone exposure. These were affected by gonadectomy and 17β-estradiol treatment in a sex-specific manner. Gonadectomized male mice displayed higher AHR than controls (sham) exposed to ozone, and hormone treatment ameliorated this response. In females, ovariectomy reduced ozone-induced AHR, which was restored by 17β-estradiol treatment. Ozone exposure increased lipocalin-2 levels in both females and males, and these were reduced in gonadectomized mice. Treatment with 17β-estradiol restored lipocalin-2 in females but lowered it in males. Gonadectomy affected expression of inflammatory genes induced by ozone exposure in both males and females; expression of IL-6 and MIP-3 was strongly dependent on 17β-estradiol levels in females. Together, these results indicate that sex hormones modulate ozone-induced inflammation and AHR. Future studies examining diseases associated with air pollution exposure should consider the patient’s sex and hormonal status.
Sex and Age Differences in Ischemic Stroke: Role of Gonadal Steroids
Farida Sohrabji1
1Women’s Health in Neuroscience Program, Department of Neuroscience and Experimental Therapeutics, Texas A&M University HSC, Bryan, TX, USA
Ischemic stroke risk is significantly affected by 2 nonmodifiable factors, age and sex. Males are at a greater risk for stroke overall and specifically at younger ages. With advancing age, women have a greater risk for stroke, and the loss of ovarian hormones (after menopause) is often cited as the underlying cause for this increased risk. Studies in preclinical models show that stroke mortality, infarct volume, and behavioral impairment is worse in young males as compared to young females. Furthermore, this advantage is abrogated by bilateral ovariectomy and reinstated by estradiol treatment, indicating that estrogens may be neuroprotective in young females. However, our studies show that hormone effects are modified by reproductive age. In addition to young normally-estrus cycling females, these studies also utilized reproductively senescent middle-aged (10-12 months old) female rats, characterized as acyclic by daily vaginal smears and low levels of circulating estradiol. Stroke outcomes in middle-aged females are worse than young females and similar to those of age-matched males, indicating that the loss of ovarian hormones may contribute to poor stroke recovery. However, unlike young females, where estradiol treatment is neuroprotective, estradiol treatment to middle-aged females is paradoxically neurotoxic. A search for alternate neuroprotective compounds further shows that both age and sex can modify the effectiveness of these agents. Using microRNA mimics or antagomirs, our studies show that antagomirs to Let7f improves stroke outcomes in young females but not young and middle-aged males or middle-aged females. In contrast, mir363-3p is effective in adult and middle-aged females but not in males of either age, while mir20a-3p is effective in males and females at either age. These studies suggest that gonadal hormones significantly modify stroke recovery and can also impact the effectiveness of other therapies.
Influence of Sex and Hormones on Brain and Behavioral Responses to Smoking Cues, a Major Relapse Predictor
Teresa R. Franklin1, Kanchana Jagannathan1, K. Ariel Ketcherside1, Nathan Spilka1, Hengyi Rao1, and Reagan R. Wetherill1
1University of Pennsylvania, Philadelphia, PA, USA
Women have greater difficulty quitting smoking and suffer greater smoking-related health consequences than men. Thus, there is an urgent need to identify sex-specific risk factors for nicotine use disorder (NUD) in order to develop individualized prevention and treatment strategies for women. Sex hormones play an important role in establishing and maintaining sex-specific brain structure and function, and as such, are primary targets for investigating sex differences in smoking-related behavior. Thus, one goal of our lab is to examine the effects of sex and hormones on exposure to smoking-related stimuli (cues), a major factor precipitating relapse. We have shown that both biological sex and hormones profoundly affect smoking cue-induced craving and neural responses to smoking cues (SCs). Although both men and women report SC-induced craving, neural responses in reward-related circuitry (ie, ventral striatum, ventral medial prefrontal cortex) are stronger in men. However, women’s responses may be influenced by hormonal fluctuations in estradiol (E) and progesterone (P) that occur throughout life, and over the course of the menstrual cycle (MC). Indeed, our work examining the effects of MC phase on SC reactivity support this concept. Women in the follicular phase (FPs) of the MC reported SC-induced craving while women in the luteal phase (LPs) did not. Compared to LPs, FPs showed greater reward-related responses. Further, in FPs, SC-induced craving correlated with activation of a known craving substrate, the anterior ventral insula. While intriguing, these results are limited because women were grouped according to MC phase without hormonal verification. Preliminary data in women grouped prospectively by MC phase (biochemically verified) concur with our earlier results; FPs show greater SC-elicited responses in reward circuitry. Our work highlights the importance of considering sex and ovarian hormones during NUD treatment planning.
Female Are Protected From Neurovascular Dysfunction Induced by Arterial Stiffness in Mice
Jessica Youwakim1, Gervais Muhire1, Diane Vallerand1, and Hélène Girouard1
1Université de Montréal, Montreal, Quebec, Canada
Arterial stiffness is associated with cardiovascular disease such as hypertension and is considered a strong risk factor for poor brain aging and stroke. Arterial stiffness in large arteries refers to the reduced capability of these vessels to buffer pulsatile blood flow from ventricular ejection. Consequently, mice with carotid calcification exhibit increased blood flow pulsatility in cerebral blood vessels, which could potentially compromise the cerebral microcirculation. Interestingly, in animal model, female have exhibited protection against cerebrovascular injury. These neuroprotective effects were associated with higher estrogen level in female. In humans, the estrogen decline during the menopause is associated with increased risks of cardiovascular diseases and stroke. Therefore, we hypothesized that estrogen would protect female mice from altered cerebrovascular functions associated with arterial stiffness. We used a model of arterial stiffness based on carotid calcification and an ovariectomy (OVX) model to mimic decrease estrogen levels in female mice. Cerebral blood flow (CBF) was monitored in vivo using laser-Doppler flowmetry in anesthetized C57BL/6J male, non-OVX, OVX + vehicle, and OVX + estradiol female mice with a cranial window. The carotid artery mechanical properties were assessed with an ex vivo technique and calcium content was determined by a colorimetric method. The results show that arterial stiffness attenuates the CBF increase induced by whisker stimulation or the endothelium dependent vasodilator, acetylcholine, in male mice (P < .05, n = 5-6). However, female mice are protected. This protection is suppressed by estrogen depletion due to the OVX (P < .05, n = 5-6) and restored by an estradiol treatment in OVX mice (P < .05, n = 5-6). However, estradiol does not reduce calcium content in carotid arteries nor improve mechanical properties. These findings suggest that female mice are protected from the effects of arterial stiffness on cerebrovascular. This protection disappears with estrogen deficiency and is reestablished with estradiol. Therefore, arterial stiffness and/or estradiol-dependent pathway should be considered as relevant targets to protect the brain.
Identifying Health Research Priorities Among Trans, Two Spirit, Non-Binary and Gender Diverse Individuals in BC: Planning a Provincial Prospective Cohort Study
Jill Chettiar, MD, MPH1,2, Lulu Gurney1, Tara Lyons, PhD1,3, Andrea Krüsi, PhD1,4, and Kate Shannon, PhD, MPH1,4
1Centre for Gender and Sexual Health Equity, Vancouver, British Columbia, Canada
2Western University, London, Ontario, Canada
3Kwantlen Polytechnic University, Surrey, British Columbia, Canada
4University of British Columbia, Vancouver, British Columbia, Canada
Sex Differences in Metabolic and Physiological Effects of a High Fat Diet in the 3xTg-AD Mouse Model of Alzheimer’s Disease
Olivia J. Gannon1, Lisa Robison1, Melissa Thomas1, Abigail Salinero1, and Kristen Zuloaga1
1Albany Medical College, Albany, NY, USA
Obesity and factors associated with metabolic syndrome are strongly associated with an increased risk for dementia. Specifically, over 80% of individuals with Alzheimer’s disease (AD) have either diabetes or prediabetes; therefore, it is of critical importance to understand the effects of this common comorbidity. Beta-amyloid deposits have been found in the pancreas of both humans and transgenic AD mouse models, thought to contribute to observed metabolic impairments. Additionally, high fat-diet induced obesity aggravates AD pathology, suggesting a feedback loop exists between these 2 conditions. In the current study, we used a high fat (HF; 60% fat) diet in a genetic mouse model of AD to induce prediabetes, which is 3x more common than diabetes and affects 38% of Americans. In addition, since females have higher rates of dementia and faster rates of decline in cognition, sex differences were explored. At 3 months of age, male and female wild-type (WT) and 3xTg-AD mice were placed on either control or HF diet for 3 months, then subjected to a glucose tolerance test, followed by blood and tissue collection. High-fat diet increased body weight gain and fat mass, and impaired glucose tolerance, to a greater degree in 3xTg-AD females compared to males. While heart mass was unaffected by diet in WT mice, HF diet increased heart mass in female 3xTg-AD mice. Additionally, HF diet reduced reproductive organ weight in 3xTg-AD females. Liver steatosis and inflammatory cytokine expression are also being assessed. Results thus far suggest that AD females are particularly sensitive to the detrimental effects of HF diet, in line with greater cognitive impairments observed in our other studies. This study will be critical for understanding sex differences in the effects of high-fat diet on metabolic and physiological outcomes that may contribute to cognitive decline in AD.
Sex Differences in Estrogenic Regulation of the Synaptic Proteome
Deepak P. Srivastava1, Pooja Raval1, Jayanta Mukherjee2, Katherine J. Sellers1, Hannah Creeney1, Rodrigo R. R. Duarte1, Stephen J. Moss2, and Nicholas J. Brandon3
1King’s College London, London, United Kingdom
2Tufts University Medical School, Boston, MA, USA
3AstraZeneca Neuroscience IMED, Waltham, MA, USA
Estrogens, particularly 17beta-estradiol (estradiol), have been shown to have long-lasting influences over learning and memory. The mechanisms underlying these effects are driven partly through activation of signalling cascades. Growing evidence indicates that estradiol can also rapidly modulate local protein synthesis (translation); the ability to produce nascent proteins near or at synapses, independent of gene transcription. However, how estradiol regulates local protein synthesis, whether this affects synaptic function, and whether male and female brains use the same signalling mechanisms to regulate this process are unclear. Using a combination of Surface Sensing of Translation (SUnSET) and fluorescent non-canonical amino acid tagging (FUNCAT) assays, we demonstrate that estradiol increases protein synthesis in acute hippocampal slices prepared from 10-week-old male and ovariectomized (OVX) female mice. Increased protein synthesis was independent of gene transcription indicting a local protein synthesis mechanism. Concurrently, an increase in the amount of newly synthesised protein was detected at synapses following estradiol treatment. This was further reflected by an increase in select synaptic proteins and an increase of these proteins at dendritic spines. Critically, the signalling pathways required for estradiol-induced protein synthesis differed between males and OVX females. Surprisingly, this was not always reflected when individual proteins were examined, suggesting that estradiol employs both distinct and common signalling pathways to regulate the local synthesis of specific synaptic proteins. Taken together, our study suggests that the rapid modulation of local protein synthesis by estradiol may result in an increase in synaptic function in male and females and thus, contribute to the facilitation of cognition offered by estrogens; this, however, occurs via distinct signalling mechanisms between sexes.
Molecular Mechanisms of Sex Differences in Pediatric Brain Tumors
Joshua B. Rubin1
1School of Medicine, Washington University
Sex differences in malignant brain tumors exist across all stages of life and are evident, with few exceptions, regardless of tumor histology or oncogenic mechanisms. We hypothesized that in utero events must confer different vulnerabilities to malignant transformation in males versus females, a view supported by the similarities in sex-specific brain tumor differences in humans, canines, and mice. We are investigating the developmental origins of sex-specific thresholds for transformation in Cas9 expressing four-core genotype (FCG) mice. Thus far, we have focused on 2 oncogenic mechanisms in glioblastoma (GBM), the most common malignant brain tumor. The first is missense mutations of the p53 DNA binding domain (DBD), which can exhibit coordinate loss of canonical gene regulation and gain of aberrant transcriptional activity. We determined that specific recurrent p53 DBD mutations in human GBM can occur with equal frequency in males and females or exhibit significant sex bias in their prevalence. We determined that loss of canonical p53 function alone is not sufficient for sex differences in tumorigenesis and conclude that it is the gain of function (GOF) activity that determines the sex-specificity. In order to investigate this hypothesis, we pursued a second question; whether sex differences in Brd4 function result in sex-specific transcriptional output for p53 DBD mutants with GOF. Brd4 is an epigenetic reader that is required for p53 transcriptional activity. We determined there are genome wide sex differences in Brd4 localization to enhancers and are working to determine whether this is required for sex differences in mutant p53 function.
Palpitations in Women
Karin Schenck-Gustafsson1, Carina Carnlöf1, and Per Insulander1
1Karolinska Institute and Karolinska University Hospital, Stockholm, Sweden
Palpitation is common, particularly in women, and may cause disturbing symptoms, anxiety, depression, and decreased health-related quality of life (HRQOL). The aim of the Red Heart Study was to evaluate if instant analysis of underlying heart rhythm during palpitations reduces symptoms, anxiety, depression, and increase HRQOL, and if there is a difference between pre- and postmenopausal women. We informed about the study in connection with our yearly women’s heart campaign in 20 cities. Recruitment was performed via social websites and for the first time, via a new form of eAuthentication via BankID when having the informed consent of the study. We intended to include 1000 participants via internet. During the first weeks in May 2018, totally, 2387 women reported interest to participate. Of these, the first 1132 were invited and finally 913 were included. The women who completed the study were between 21 and 88 years (338 ≤ 52 years and 557 ≥53 years old). Mean age in the prepostmenopausal groups was 44 ± 7 versus 63 ± 7 years. Coala Heart Monitor was used by the participants and thumb and chest ECG were recorded twice a day and at symptoms during 60 days. The system uses a well-validated algorithm to analyze heart rhythm and is connected to the user’s smartphone and provides immediate response to the user. Questionnaires addressing symptoms like anxiety, depression, HRQOL were analyzed before and after 60 days. Exclusion criteria was known atrial fibrillation. At start, premenopausal scored higher than postmenopausal women in scales of total anxiety and depression and lower HRQOL. After 60 days with the heart monitor, the younger women were still symptomatic and improved less in HRQOL than the postmenopausal women who generally felt better. In the great majority of episodes causing symptomatic palpitation in women, the underlying arrhythmia was benign. However, in 4% previously undiagnosed atrial fibrillation or supraventricular tachycardia were found. We concluded that instant analysis of the ECG with direct response to the user during palpitations reduce symptoms, anxiety, depression, and increase HRQOL in postmenopausal but not so much in premenopausal women. Also, this totally web-based study approach including, for the first time, the use of eAuthentication for informed consent, facilitated the inclusion time and was appreciated both by the study participants and the researchers.
Sex-Dependent Effects of Paternal Deprivation and Chronic Stress on Cognitive Performance in Adult California Mice (Peromyscus californicus)
Priyanka Agarwal1, Nicole Palin1, Shakeera L. Walker1, and Erica R. Glasper1
1University of Maryland, College Park, MD, USA
Early-life stress (ELS) exposure can confer vulnerability to development of psychiatric illness and impaired cognition in adulthood. It is well-known that ELS can dysregulate the hypothalamic–pituitary–adrenal (HPA) axis in a sex-dependent manner. Specifically, uniparental rodent models of prolonged disrupted maternal-offspring interactions (eg, maternal separation) have demonstrated greater alterations in stress responsivity in adult males, compared to females. Additionally, chronic ELS (eg, limited bedding model) impairs cognitive function to a greater extent in males, compared to females. However, the sex-dependent effects of ELS and chronic HPA axis activation on cognitive ability has not been well characterized. Using a novel model of ELS (ie, paternal deprivation [PD]), we hypothesized that ELS would confer sex-dependent vulnerability to chronic stress and cognitive performance in adulthood. Using the biparental California mouse (Peromyscus californicus), fathers either remained in the nest (biparental care) or were permanently removed (PD) on postnatal day (PND) 1. Adult offspring were either exposed to daily handing (control) or chronic variable stress (CVS; 3 stressors for 7 days). Twenty-four hours after the final stressor, all mice performed the novel object recognition (NOR) task and were euthanized to collect serum for corticosterone (CORT) analysis. CVS increased serum CORT overall, except in PD males. ELS and CVS resulted in sex-dependent effects on behaviors during the NOR task. Among control mice, PD increased recognition memory in females; however, recognition memory was reduced in PD females exposed to CVS—an effect not observed in males. In females, the additional challenge of CVS mitigated the cognition-enhancing effects of PD despite similarities in circulating CORT. Overall, these data suggest that the absence of paternal care influences cognition and stress hormone levels in adult offspring in a sex-dependent manner.
Sexually Dimorphic Impact of Prenatal Chemical Exposures on Newborn Metabolic Outcomes
Vasantha Padmanabhan1, Margaret Banker1, Jennifer LaBarre1, Muraly Puttabyatappa1, Charles Burant1, Dana Dolinoy1, Jaclyn Goodrich1, and Peter Song1
1University of Michigan, Ann Arbor, MI, USA
Over the past 30 to 40 years, there has been an increase in noncommunicable diseases (NCDs). Environmental endocrine disrupting chemicals (EDCs) are gaining recognition in the development of NCDs. During development, the fetus is vulnerable to insults, therefore we hypothesized that early pregnancy exposure to phenols, phthalates, and metals would have an impact on the neonatal inflammasome, oxidative stress, epigenome, lipidome, and birth weight (BW). Women in the Michigan Mother-Infant Pairs (MMIP) cohort provided urine during their first trimester. Maternal urine, cord blood and placental samples were also collected at delivery and offspring BW obtained from medical records. Our findings point to several sexually dimorphic associations of maternal EDC exposure with neonatal outcomes, namely (1) high first trimester bisphenol-A with hypomethylation of cord blood insulin-like growth factor-2 and peroxisome proliferator-activated receptor-α and reduced BW only in females, (2) positive first trimester phenols and phthalates with dityrosine (female-specific), (3) several phthalate metabolites with BW (sex and time of exposure specific), and (4) negative first trimester phenols with nitrotyrosine only in females. A positive correlation was found between chromium accumulation in the placenta and oxidative stress, with a sex bias toward males. Maternal first trimester saturated triglycerides (TGs) were positively associated with BW only in males. Additionally, an inverse correlation was observed between the number of double bonds in neonatal TGs and BW in females, emphasizing the importance of polyunsaturated TGs in female growth patterns. Future analyses need to address if the lipidome mediates the observed sex-specific effects of EDCs on neonatal oxidative stress and the epigenome. These findings provide support for EDCs having a major impact on the neonatal metabolic status and birth outcomes, established risk factors for development of metabolic diseases.
Considering Sex Differences in Treatment Development for Smoking
Sherry A. McKee1
1Yale School of Medicine, New Haven, CT, USA
Several lines of evidence identify that women experience significant disparities with regard to smoking cessation. Women who smoke experience exacerbated health risks compared to men and have more difficulty quitting smoking. In this presentation, Dr McKee will present translational findings spanning human laboratory, clinical trial, and meta-analyses which considers sex in the treatment development for smoking cessation. She will first present an overview of meta-analytic findings involving 29 000 smokers, examining sex differences the efficacy of FDA-approved smoking cessation medications. Overall, findings indicate that varenicline produces either equal or preferential smoking cessation outcomes for women, which is notable as bupropion and nicotine patch are less effective for women. For men, all 3 medications are equally effective and demonstrate no differences in efficacy. Next, Dr McKee will present human laboratory and clinical trial findings targeting stress reactivity for medication development. To improve rates of smoking cessation in women, medication needs to target factors which maintain smoking behavior in women. To this end, Dr McKee has pursued a program of research based on the working hypothesis that female smoking behavior is more likely to be motivated by affect regulation and stress, whereas male smoking behavior is more likely to be motivated by nicotine-related reinforcement. To date, her work has demonstrated that targeting the noradrenergic system with guanfacine is an effective strategy for women smokers. Specifically, guanfacine (an α2a noradrenergic agonist), reduces stress reactivity in women and increases rates of smoking cessation.
Ischemic Heart Disease and Gender Differences Affecting Survival
Mariyam Habeeb, BA, BS1, Frank H. Netter, MD2, and Dalia Giedrimiene, MD, PhD3
1Quinnipiac University
2School of Medicine
3Hartford Hospital, University of Saint Joseph
The emphasis on gender-specific cardiovascular disease (CVD) research and improved understanding of sex-specific pathophysiology expanded insights into ischemic heart disease (IHD) in women. Despite this progress, women with IHD experience relatively worse outcomes compared to men and younger women (<55 years) including subgroups defined by race, ethnicity, socioeconomic status, and educational level still show striking disparities in cardiovascular health. The aim of this study was to identify the gender-based differences in the management of IHD in menopausal and younger women by identifying the most important concerns. A systematic review of existing literature regarding IHD in women >18 years was performed, and of the 729 publications from 2016 to 2018 selected, 20 have been chosen for analysis by filtering for key words “Gender” and “Sex” in the title. The comparison of published data on IHD pathophysiology showed that women have smaller, stiffer vessels with more fibrosis and microemboli than men, which can be a contributing factor to the higher rate of microvascular coronary dysfunction. Psychosocial risk factors, such as depression and poorer self-reported health is also higher in women. Women with IHD tend to be older, more likely to have hypertension, less likely to smoke, and have worse left ventricular systolic function than men. They have higher rates of diabetes, obesity, renal dysfunction, chronic lung disease, prior stroke, and autoimmune disorders. Young women have worse physical and mental pre-event health status compared to men. They have angina more frequently, less treatment satisfaction, worse quality of life, and are more likely to be black, single, unemployed, and have no health insurance. The mortality rate is double that of men for older women >65 years. Overall, women are treated less aggressively and are less likely to receive optimal care at discharge, which may lead to higher mortality and more adverse outcomes.
Cardiac Arrhythmias During Pregnancy. What Are the Most Common Risk Factors?
Vy Nguyen, MS1, F. H. Netter, MD2, and Dalia Giedrimiene, MD, PhD3
1Quinnipiac University
2School of Medicine
3Hartford Hospital, University of Saint Joseph
Cardiac arrhythmias in women, especially those with heart disease (HD), can result in increased risk to the mother and fetus during the pregnancy. Physiological changes of pregnancy increase the likelihood of de novo or recurrent cardiac arrhythmias, where atrial fibrillation (AF) is the most common. Although other types of arrhythmias are less common, mothers with structural HD have higher risk of developing these arrhythmias in pregnancy compared to their counterpart. Hence, early diagnosis and risk stratification are needed for successful management of pregnancy for these women with structural HD. The purpose of the study is to determine the risk factors associated with arrhythmia recurrence during pregnancy in women with and without structural HD, and HD impact on pregnancy outcomes. Using the search terms “cardiac arrhythmia, women, and pregnancy,” 16 publications were found on PubMed. Of all, 12/16 were used in the final analysis as they were within 5 years of publication and had participants older than 18. Most patients without structural HD had genetic predisposition of long QT (LQTS) or WPW syndrome. During labor, mothers with LQTS rarely developed cardiovascular events due to beta blockers therapy, which had a preventive effect on arrhythmias. Pregnancy with LQTS had a higher caesarean delivery rate due to nonreassuring fetal heart rate, potentially associating with fetus-inherited LQTS. Women with structural HD most commonly had AF. The majority of women with prediagnosis of AF prior to pregnancy had uncomplicated pregnancy, but 34.9% had AF during pregnancy or 6 months postpartum. Certain factors, such as increased maternal age and white race, increased the odds of having AF. Pregnancy increases the risk of de novo arrhythmia or recurrent arrhythmia. A prior history of arrhythmias (including inherited arrhythmia-related syndromes) and structural HD are the major risk factors of cardiac arrhythmias during pregnancy.
Sex Differences Detected in Infant Circulating MicroRNAs in Fetal Alcohol Spectrum Disorders
Amanda H. Mahnke1, Georgios D. Sideridis2, Nihal A. Salem1, Alexander M. Tseng1, R. Colin Carter3, Neil C. Dodge4, Aniruddha B. Rathod1, Christopher D. Molteno5, Ernesta M. Meintjes5, Sandra W. Jacobson6, Rajesh C. Miranda1, and Joseph L. Jacobson5,6
1Health Science Center, Texas A&M University, Bryan, TX, USA
2Harvard Medical School, Boston, MA, USA
3College of Physicians, Columbia University, New York City, NY, USA
4College of Medicine, Wayne State University, Detroit, Michigan, USA
5Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
6School of Medicine, Wayne State University, Detroit, Michigan, USA
Prenatal alcohol exposure (PAE) can result in growth and neurodevelopmental delays termed fetal alcohol spectrum disorders (FASD). Since not all children with PAE present with the overt physical characteristics of FASD, there is a need for biomarkers that indicate both PAE and child outcome. Previous work has shown that maternal circulating miRNAs in blood (cirmiRNAs) can indicate PAE and also predict which exposed infants develop behavioral or growth deficits. Here, we present evidence that infant cirmiRNAs can detect PAE and predict infant growth and developmental outcomes. We examined cirmiRNA expression in infant plasma, from a heavily exposed Cape Town cohort, obtained at 2 weeks and 6.5 months. PAE significantly altered cirmiRNA expression, some with large effect sizes (d > 0.8). Examination of effect size by infant sex showed that some effect sizes were largely driven by a single sex, for example, miR-21-5p (female: 0.84; male: 0.05). We examined the stability of these sex differences using bootstrap resampling to simulate a larger population. We found a number of cirmiRNAs were more likely to be significantly altered in one sex than in the whole population and that the number of sex-specific miRNAs increased over development. For the entire population, preliminary confirmatory factor analysis clustered altered cirmiRNAs into factors based on biological function, including growth, inflammation, and stress pathways. Mediation analysis showed that cirmiRNA expression in 2 week factors correlated with growth deficits. At 6.5 months, cirmiRNAs in the stress-associated factor partially mediated PAE effects on cognitive function. These findings demonstrate that PAE alters infant cirmiRNA profile and that these cirmiRNAs are predictive of growth and neurocognitive outcome. Further research is warranted to understand the direct relation between altered cirmiRNAs and child outcomes as well as the potential contribution of child sex to cirmiRNA profile.
Sex and Age Associated Differences in Antibody Responses to Influenza Vaccination
Kristyn E. Sylvia1, Tanvi Potluri1, Ashley L. Fink1, and Sabra L. Klein1
1Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
Epidemiological observations, clinical trials, and preclinical animal models illustrate that sex and age independently impact the outcome of influenza virus infection and responses to vaccination. Few studies have considered the interaction between biological sex and age when evaluating the efficacy of influenza vaccines. The goal of this study was to use human sera collected prior to and 21 days after receipt of the monovalent pandemic A/Cal/09 H1N1 vaccine from pediatric (NCT00944073) and adult (NCT00943488) clinical trials from the National Institutes of Health Division of Microbiology and Infectious Diseases Center for Excellence in Influenza Research & Surveillance network to characterize sex and age differences in neutralizing antibody (nAb) responses. We analyzed samples collected from 3 age groups: (1) children (ages 0-9 years); (2) reproductive adults (ages 18-49 years); and (3) aged adults (ages 65+ years). Secondarily, we used these samples to determine the association of sex and age differences in nAb responses with circulating sex steroid hormones. Antibody responses to A/Cal/09 H1N1 were higher among reproductive adults than either children or aged adults. Further, adult and pediatric, but not aged females, developed higher nAb responses to A/Cal/09 H1N1 than their age-matched male counterparts. In reproductive and aged females, estradiol concentrations were positively associated with nAb responses to the vaccine, though estradiol concentrations were reduced in aged females. In reproductive males, but not aged males, testosterone concentrations were negatively associated with nAb responses. Among pediatric subjects, sex steroid concentrations were low and not associated with nAb responses. Because sex differences in vaccine-induced immunity are present prior to puberty, these data suggest that sex differences in immune responses to a novel influenza strain cannot be explained by sex hormone levels alone.
Leukemia Inhibitory Factor Alters Poststroke Splenic Cytokine Expression in a Sex-Dependent Manner
Stephanie M. Davis1, Lisa A. Collier1, Sarah Goodwin1, Hemandra J. Vakaria1, Patrick G. Sullivan1, and Keith R. Pennypacker1
1University of Kentucky, Lexington, KY, USA
The goal of this study was to determine whether LIF differentially affects pro-inflammatory signaling in aged male and female animals after stroke. Eighteen-month-old male/female Sprague-Dawley rats underwent middle cerebral artery occlusion (MCAO). Animals were treated with PBS or LIF at 6, 24, and 48 hours after MCAO (125 µg/kg). Protein levels of the LIF receptor (LIFR) pro-inflammatory mediators were measured in splenic tissue using immunoblotting and ELISA. Griess assay was used to measure nitrite in spleen tissue. Statistical analyses were performed using 1 or 2-way ANOVA followed by Fisher LSD post hoc test. Aged male and female rats showed significant decreases in spleen size after PBS treatment and significant increases in spleen size after LIF treatment. Splenic LIFR in female rats was significantly increased after LIF treatment, but no change was observed in male rats. CXCL9 expression was increased after LIF treatment in rats of both sexes. Aged male rats showed significantly higher levels of IL-1β in the spleen compared to their female counterparts. LIF treatment significantly decreased levels of IFNγ after stroke in females, but not males. IL-3 levels were significantly increased in the spleens of female rats after LIF treatment compared to sham females, PBS females, and LIF males. However, drug treatment did not significantly alter splenic IL-3 levels among aged male rats. Levels of nitrite significantly increased in the spleens of aged female rats after PBS treatment, but decreased after LIF treatment. Aged males showed significantly higher levels of nitrite after LIF treatment. These results demonstrate that LIF treatment promotes alterations in mitochondrial activity and cytokine expression in the spleen at 72 hours after MCAO, with some cytokines exhibiting sex-specific differences in expression. These data demonstrate that rats show sex differences in the poststroke inflammatory response after stroke and differential responses to LIF.
Intrahippocampal Infusion of a G-Protein-Coupled Estrogen Receptor Agonist Increases CA1 Spine Density and Enhances Memory Consolidation
Jayson C. Schalk1, Jaekyoon Kim1, Wendy A. Koss1, and Karyn M. Frick1
1Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
Little is known about the role of G-protein-coupled estrogen receptors (GPERs) in hippocampal synaptic plasticity and memory consolidation. G-1 is a GPER agonist that mimics the memory-enhancing effects of 17β-estradiol (E2), a potent estrogen. However, the mechanisms through which G-1 enhances memory remain unclear. Here, we examined the effects of dorsal hippocampal G-1 infusion on memory consolidation and CA1 dendritic spines. In experiment 1, ovariectomized C57BL/6 mice received bilateral dorsal hippocampal infusion of vehicle or G-1 (4 µg) immediately after training in the object recognition and object placement tasks. Compared to vehicle, G-1 significantly increased the time spent with the novel or moved objects, indicating that GPER activation enhanced hippocampal-dependent object recognition and spatial memory consolidation. In experiment 2, ovariectomized mice received dorsal hippocampal infusions of vehicle or G-1, and then brain tissue was collected 40 minutes later for Golgi staining and dendritic spine analysis. Compared to vehicle, G-1 significantly increased apical dendritic spine density on pyramidal neurons in the CA1 region of the hippocampus. Further analysis showed that G-1 specifically increased the number of mushroom spines, but not thin or stubby spines. These findings suggest that G-1 may enhance hippocampal-dependent memory by increasing mature apical dendritic spines in CA1.
Gene Regulatory Network Analysis Identifies Sex-Linked Differences in Colon Cancer Drug Metabolism Processes
Camila M. Lopes-Ramos1, Marieke L. Kuijjer2, Shuji Ogino3, Charles Fuchs4, Dawn L. DeMeo5, Kimberly Glass5, and John Quackenbush1
1Harvard T.H. Chan School of Public Health, Boston, MA, USA
2University of Oslo
3Dana-Farber Cancer Institute, Boston, MA, USA
4Yale School of Medicine, New Haven, CT, USA
5Harvard Medical School
Sex differences play an important role in development and progression of many diseases, and understanding how a disease differs between the sexes is essential for the advancement of prevention, diagnosis, and treatment. Specifically, for colon cancer, males have a higher risk of developing the disease and a lower survival rate than women. However, the molecular features that drive these sex differences are poorly understood. We used both transcript-based and gene regulatory network methods to analyze RNA-Seq data from The Cancer Genome Atlas for 445 patients with colon cancer. We compared gene expression between tumors in men and women and found no significant sex differences except for sex chromosome genes. We then inferred patient-specific gene regulatory networks and found significant regulatory differences between males and females, with drug and xenobiotics metabolism via cytochrome P450 pathways more strongly targeted in females. This finding was validated in a data set that included 1193 patients from 5 independent studies. Most importantly, targeting of the drug metabolism pathway was predictive of higher overall survival in women who received adjuvant chemotherapy, with 89% (95% CI: 78%-100%) 10-year overall survival probability compared to 61% (95% CI: 45%-82%) for women with lower targeting (P = .034). The regulatory network analysis method described here can easily be used to understand how sex influences progression and response to therapies in other cancer types and complex diseases and may help motivate development of sex-specific approaches to disease treatment.
Sex Differences in Object Memory and Spatial Ability in Young and Aged Adults
Lauren L. Harburger1, Kathleen D. Beach1, and Ethan L. Sua1
1Purchase College
This study investigated the effects of age on sex differences in object memory and spatial ability. Based on previous research, we hypothesized that women would outperform men on tests of object memory and that men would outperform women on tests of spatial ability for all age groups. Young undergraduates (18-25 years old) were compared to aged independent living seniors (over 65 years old). An object array task was used to measure object memory and a mental rotations test (MRT) was used to measure spatial ability. The object array task required participants to study black and white drawn objects and then to circle objects that they believed had moved positions or were new to the array. The MRT required participants to match objects that were rotated into different positions. Although there was no significant sex difference in object memory performance in young subjects, aged women performed significantly better than aged men on the object array task. As we expected, young men performed significantly better on the MRT compared to young women. However, there was no sex difference in MRT performance in the aged groups. Results of this study suggest that the sex difference in spatial ability performance declines with age.
Of Mice and Wo/Men: Translating the Relationship Between Cytokines and Depression Associated Behavior
Jennifer R. Rainville1, Molly Schneider2, Flurin Cathomas3, Scott J. Russo3, James W. Murrough2, and Georgia E. Hodes1
1School of Neuroscience, Virginia Tech
2Department of Psychiatry, Icahn School of Medicine at Mt. Sinai
3Fishberg Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mt. Sinai
Within the brain, the underlying biological mechanisms of depression differ between men and women. Recent work has demonstrated the peripheral immune system influences the brain’s response to stress and subsequent behavior. The peripheral immune system is altered in patients with depression and may contribute to sex differences in the prevalence and symptoms of depression. We took an unbiased approach to examine differences in plasma cytokine expression between premenopausal women and age-matched men with depression. We modeled these changes in immune activity with mouse stress paradigms to uncover the relationship between peripheral cytokine expression and behavior. We used multiplex ELISA to quantify plasma expression levels of 29 different cytokines in plasma samples from men and women diagnosed with depression (treatment resistant vs non treatment resistant), as well as from mice of both sexes following either social defeat stress or chronic variable stress. Our results show women with treatment resistant depression have greater immune activation than any other group. We were able to model the IL-6 response in females following social defeat stress, and a similar GM-CSF response following 28-days of chronic variable stress. All cytokine concentrations were correlated with symptoms reported by patients on the Quick Inventory of Depressive Symptomology (QIDS), or with behavior scores from a battery of ethologically relevant depression-like behaviors in mice. These results confirm sex-specific immune system activation in depression, and demonstrate the translational potential for using stress paradigms in mice to model specific immune responses.
Is There a Difference in the Immune Response, Efficacy, Effectiveness, and Safety of Seasonal Influenza Vaccine in Males and Females?—A Systematic Review
Fazia Tadount1, Pamela Doyon-Plourde1, and Caroline Quach1
1Université de Montréal, Montreal, Quebec, Canada
Every year, seasonal influenza causes high-morbidity and mortality rates, despite being a vaccine-preventable disease. Several studies have demonstrated that sex factors (genes and hormones) impact individuals’ susceptibility and response to infectious diseases and vaccines. For instance, females tend to have a more robust humoral and cellular immune response compared to males, when exposed to viruses. However, most studies do not explicitly assess and report on sex differences in vaccine response despite collecting this data, rather they adjust for sex as a confounding variable. Therefore, we conducted a systematic review (SR) to analyze immunogenicity, efficacy, effectiveness, and/or safety of seasonal influenza vaccine data stratified by sex. We searched PubMed, EMBASE, CINAHL, Web of Science, and clinicaltrials.gov for observational studies and phase III/IV trials from January 1990 to June 2018, published in English or French. Two reviewers independently screened all references, then proceeded to data extraction and quality assessment using the Cochrane tools (RoB and ROBINS-I) on all the included studies. Of the 5745 citations retrieved, 46 studies were included in the SR. Overall, 15 (32.6%) studies assessed immunogenicity, 1 (2.2%) estimated efficacy, 7 (15.2%) measured effectiveness, and 23 (50%) assessed safety. Thirteen (28%) were randomized trials and 33 (72%) were observational studies. Eighteen (39%) of the studies only included adults aged older than 50 years old. We anticipate the latter studies would limit our findings, as the immune system differs in pre and postmenopausal females. Finally, we noticed many authors using the terms sex and gender interchangeably while reporting on sex differences as a biological phenomenon. Our findings support the implementation of educational modules that would emphasize on appropriate utilization of sex and gender terminology in science. Once our data analyzed, we will be able to determine whether sex matters for influenza vaccination.
Imaging Sex Differences in the Mesocortical and Mesolimbic Dopamine Pathways of Tobacco Smokers
Kelly P. Cosgrove1, Yasmin Zakiniaeiz1, Heather Liu1, and Evan D. Morris1
1School of Medicine, Yale University
Sex differences exist in the neurochemical mechanisms underlying tobacco smoking-related behaviors. Men smoke for the reinforcing effects of nicotine, whereas women smoke for stress and mood regulation, and have a much harder time quitting. The mesolimbic dopamine (DA) pathway drives the reinforcing effects of tobacco smoking, whereas the mesocortical DA pathway—including the dorsolateral prefrontal cortex (dlPFC)—is critical for stress-related cognitive functioning and inhibitory control. We used state-of-the-art receptor brain imaging techniques to systematically examine sex differences in both of these dopaminergic pathways. In a previous study, we showed that men have a significant dopamine response to smoking a cigarette in the ventral striatum, whereas women do not. This finding was in line with men smoking for the rewarding properties of nicotine since the ventral striatum is considered the “hub” of reinforcement within the mesolimbic DA system. In a more recent study, we extended our findings to cortical areas including the dlPFC. We found that tobacco smokers have lower dopamine 2/3 receptor (D2R) availability than nonsmokers and that this finding is driven by males. Specifically, male smokers have lower D2R availability in the dlPFC than male nonsmokers but female smokers are not different from female nonsmokers. Additionally, we found that female smokers have a significantly blunted amphetamine-induced DA release, compared to male smokers and to female nonsmokers. These findings demonstrate that tobacco smoking differentially affects the mesolimbic and mesocortical DA pathways in men versus women, and suggests potential neurochemical targets for sex-specific smoking cessation treatments.
Genital Stimulation Facilitates a Sexual Reward State in Male and Female Mice
Thanh Phung1, Firyal Ramzan1, and D. Ashley Monks1
1University of Toronto, Toronto, Ontario, Canada
Genital tactile stimulation is seen as a precursor to sexual arousal and is recognized as an initiator of CNS arousal. Previous rodent studies have demonstrated that tactile stimulation of the clitoris is sufficient enough to induce a reward state in female rats. However, it is currently unknown whether tactile stimulation of the genitals could also induce a similar hedonic state in male rodents. The present study examined the ability of clitoral and glans penis stimulation to induce a conditioned place preference (CPP). Sexually naïve and gonadally intact C57BL/6 mice (both male and female) were randomly assigned to receive either genital stimulation or dorsum stimulation. Stimulation was conducted at a rate of 1 stimulation per second for 1 minute prior to being placed in one distinctive side of a nonbiased CPP box for 2 minutes. A session of conditioning consisted of 5 rounds of stimulation and place exposure per day. Conditioning sessions alternated with sham sessions in which mice were similarly handled but no tactile stimulation occurred. Place exposure was for nonpreferred side (conditioning) and preferred side (sham). CPP was assessed once all animals had completed 5 conditioning and sham sessions. It was found that all animals subjected to genital stimulation developed a significant CPP, whereas a significant CPP for dorsum stimulation was only developed in male mice. This suggests that despite morphological differences, the clitoris and the glans penis possess a similar role in generating a reward state upon stimulation. Additionally, the development of a significant CPP in male mice who received dorsum stimulation highlights a sex-difference in tactile reward.
Paternal Deprivation Induces Sex-Dependent Effects on Social Anxiety and Preference for Social Novelty in Adult California Mice (Peromyscus californicus)
Shakeera L. Walker1, Neilesh Sud1, Nicole Palin1, and Erica R. Glasper1
1University of Maryland, College Park, MD, USA
Early-life stress (ELS) is implicated in the development of anxiety-related disorders and social impairments. Recent evidence suggests relations between offspring and fathers may contribute to ELS-related outcomes. The biparental California mouse (Peromyscus californicus) is a rodent model used to study paternal deprivation (PD; a model of ELS), as paternal California mice provide extensive parental care and are necessary for offspring survival and typical development. In California mice, PD can induce sex-dependent deficits in social and anxiety-like behaviors. Given the comorbidity between impaired social behaviors and psychiatric disorders, we hypothesized that PD would induce sex-dependent alterations in sociability and general anxiety-like behaviors using the 3-chamber social interaction test and novelty-suppressed feeding (NSF) test, respectively. Overall, female California mice displayed social avoidance behavior regardless of rearing during the 3-chamber social interaction test; however, this effect was more profound in PD females. When compared to biparentally reared males, social avoidance behavior was only displayed in males following PD. Moreover, PD decreased preference for social novelty in females, but did not alter preference for social novelty in males. Sex and rearing effects on social avoidance and preference for social novelty were not a result of reduced locomotion in PD females, as PD females increased the distance traveled during the social interaction test, compared to biparentally-reared females and PD males. The effects of PD on generalized anxiety (ie, NSF task) were weak, but anxiogenic environmental conditions decreased food intake in PD females only. Taken together, PD results in sex-dependent effects on social anxiety and preference for social-novelty during adulthood, suggesting that PD may have a more harmful effect on social behaviors in females.
Transcriptional Profiling of the Stressed Hippocampus: Does Sex Make a Difference?
Jordan Marrocco1, Nathan R. Einhorn1, Claire Le Floch1, Axel Lihagen2, Gordon H. Petty3, Francis S. Lee4, and Bruce S. McEwen1
1The Rockefeller University, New York, NY, USA
2Linköping University, Linköping, Sweden
3Columbia University
4Weill Cornell Medical College, New York City, New York, USA
Females and males adopt distinct brain circuits to cope with similar environmental challenges. Whole genome analysis of discrete cell populations has advanced the dissection of circuits responding to stress, such as the hippocampal subfields. Recently, RNA sequencing of a homogenous population of CA3 pyramidal neurons showed that female mice display greater gene expression activation after an acute stressor than males, while also expressing unique gene pathways. We examined the transcriptomic profiling, along with behavioral correlates and neuroarchitecture changes, in mice maintained on chronic low-dose (25 mg/mL) oral corticosterone (CORT), a mouse model showing a blunted response to acute stress. Anxiety- and depression-like behaviors, referred to as emotional behavior, were tested with the light-dark box and the splash test, respectively. A Z-normalization applied across complementary measures of behavior showed that CORT increased emotional behavioral scores in males but not in females. However, when maintained on chronic oral CORT, both females and males exhibited comparable loss of dendritic complexity and length in the ventral dentate gyrus. We then dissected the ventral hippocampus to study the transcriptional profiling of either sex and found that chronic oral CORT triggered diverse gene sets in male and female mice, with males inducing a larger number of genes than females. Although CORT overexposure leads to similar morphological changes in the ventral hippocampus of female and male mice, there are sex differences that intersect affective behavior and transcriptional signature. This favors the use of big data to probe dissimilar gene functions that underlie sex-specific endophenotypes in animal models of stress.
Effects of Estrogen Depletion, Age, and Functional Brain Activity on Associative Memory in Spontaneous Menopause and Surgically-Induced Menopause
Alana Brown1, Anne Almey1, Nicole J. Gervais1, Annie Duchesne2, Laura Gravelsins1, Elizabeth Baker-Sullivan1, Daniel Nichol3, Giulia Baracchini3, William Foulkes4, Wendy Meschino5, Cheryl Grady1,3,6, Gillian Einstein1,3, and Tema Genus7
1Psychology, University of Toronto, Toronto, Ontario, Canada
2University of Northern British Columbia, Prince George, British Columbia, Canada
3Rotman Research Institute, Baycrest Health Sciences, Toronto, Ontario, Canada
4Department of Human Genetics, McGill University, Montreal, Quebec, Canada
5Genetics Program, Department Paediatrics, North York General Hospital, University of Toronto, Toronto, Ontario, Canada
6Psychiatry, University of Toronto, Ontario, Canada
7Linköping University, Linköping, Sweden
Surgical removal of the ovaries via bilateral salpingo-oophorectomy (BSO) prior to spontaneous menopause (SM) is correlated with increased Alzheimer disease (AD) risk. The objective of this study is to clarify the distinct roles of estrogen loss and age on memory and functional brain activity in the anterior hippocampus (aHPC) and frontoparietal attention network during associative encoding. Paired associative learning deficits are considered the earliest and most salient AD symptoms, heralding preclinical AD. There is little understanding of the influence of depletion of 17β-estradiol (E2), on associative memory following BSO. We administered a face-name associative memory task that is sensitive to prodromal AD. Using fMRI, we assessed brain activity during face-name pair encoding and compared recognition performance of women who underwent BSO to that of age-matched premenopausal control (AMC) and SM women. We hypothesized that BSO would be associated with the lowest accuracy, with E2-based hormone therapy (HT) attenuating this effect, and that this would be related to decreased aHPC and increased prefrontal cortex activity during successful encoding. We also hypothesized that SM women would perform worse than AMCs, and that this would be associated with increased frontoparietal activity during encoding. Our results show SM was associated with the lowest recognition accuracy compared to BSO and AMC (P < .05). SM and BSO women (not taking HT) had comparable circulating E2 levels, and BSO women were, on average, 11 years younger than SM women, suggesting that age affects associative ability more strongly than E2 loss. fMRI results clarify the distinct impacts of BSO and SM on activity in the aHPC, amygdala, and prefrontal and parietal cortices during encoding. Understanding functional activity variations between these groups during associative learning is critical for distinguishing memory effects resulting from normal aging versus E2 loss.
Applying a Gender Lens to the Surveillance of Sedentary Behaviour in Canada
Stephanie A. Prince1,2, Alexandria Melvin1, Karen C. Roberts1, Gregory P. Butler1, and Wendy Thompson1
1Centre for Surveillance and Applied Research, Public Health Agency of Canada
2Division of Cardiac Prevention and Rehabilitation, University of Ottawa Heart Institute
Sedentary behaviour (SB; time spent sitting/reclining/lying awake) is ubiquitous in our modern day. Gender is an important sociocultural determinant of health that influences SB through socially constructed norms and roles. Gender-informed analyses help us understand SB. We applied a gender lens to examine SB in nationally representative Canadian surveys to see if girls and boys or women and men engaged in different amounts and types of SB. Descriptive data in youth (12-17 years) and adults (≥18 years) on SB were examined over time in multiple cycles of the Canadian Community Health Survey (CCHS; self-reported type-specific SB) and the Canadian Health Measures Survey (device-measured total SB). Data were stratified to identify differences in SB between genders. Device-measured total SB time did not differ between genders. Over time, boys/men engaged in significantly higher amounts of leisure video game use than girls/women. Leisure-time reading tended to be significantly higher in girls/women than boys/men; however, in recent years this gender gap in adults diminished. In older cycles, men reported higher amounts of leisure computer use than women, with the gap narrowing more recently. From 2000 to 2007, boys reported greater leisure computer use than girls; however, in 2015 to 2016, girls reported higher amounts than boys. From 2000 to 2005 men reported greater amounts of leisure TV use, however, this gap was not observed in recent years (except 2015). Generally, no gender differences were observed for leisure TV watching in youth. In older cycles, significantly more girls than boys met leisure screen time guidelines (≤2 h/d); recently this gender gap has narrowed. In conclusion, while no differences were found for total SB, gender differences in type-specific SB exist. This information is valuable for identifying the target audience and behaviours for SB policies and interventions. Future work is needed to further understand factors contributing to these differences.
Sex Differences in the Forebrain Dopaminergic Circuit
Matthew Coon1,2, Grace Wang3, Erica R. Glasper2, Yogita Chudasama1, and Kuan Hong Wang4
1National Institute of Mental Health
2University of Maryland, College Park, MD, USA
3Stanford University, Stanford, CA, USA
4University of Rochester Medical Center
Several psychiatric disorders, like schizophrenia, exhibit different incidence rates in men and women and are associated with dysfunctions in forebrain dopaminergic circuits. Although anatomical and functional sex differences in the brain have been studied, little is known about sex differences in the forebrain dopaminergic circuits associated with behavioral dysfunction. We hypothesized that sex differences in forebrain dopamine circuit anatomy would be associated with sex differences in forebrain dopamine-dependent behaviors. As a first step to address this hypothesis, we combined a mouse transgenic driver line (tyrosine hydroxylase promoter-driven Cre recombinase) with virally encoded fluorescent reporters (flexed tdTomato and synaptophysinGFP) to compare the density of midbrain dopaminergic axon projections and terminal boutons. Using this technique, we analyzed projections from the ventral tegmental area (VTA) to prefrontal cortex and basolateral amygdala (BLA) in male and female adult mice. Initial analysis with broad low-magnification (×10) images revealed higher bouton density in BLA in males compared to females. This sex difference was further replicated using an automated stage to acquire high-magnification (×25) confocal images tiled over these regions for improved representation compared to the original conditions. This anatomical difference in the forebrain dopamine circuit will provide a structural foundation for further investigation of how sex differences in brain circuits may underlie behavioral dysfunction that play roles in psychiatric illnesses.
Probiotics Mitigate Lipopolysaccharide-Induced Reduction in Glucocorticoid Receptor Expression in Male Mice
Kevin Smith1, James Gardner Gregory1, Emma Murray1, and Nafissa Ismail1
1University of Ottawa, Ottawa, Ontario, Canada
Puberty is a sensitive period of cortical and neuronal development. Stress during this time can cause long-lasting changes to the brain and behaviour. Probiotics have been shown to mitigate the effects of stress, however, the mechanism remains elusive. The goal of this study was to investigate the programming effects of pubertal LPS-injections on glucocorticoid receptor (GR) expression in the paraventricular (PVN), basolateral amygdala (BLA), piriform cortex (PIR), and medial prefrontal cortex (mPFC). Mice were administered probiotics for 2 weeks (from 5 to 7 weeks of age) and treated with either saline or LPS at 6 weeks of age. Prior to euthanasia in adulthood, mice were restrained for 30 minutes. Immunocytochemistry was used to measure GR expression in regions associated with hypothalamic pituitary adrenal (HPA) axis activation. The results showed that LPS treatment decreased GR expression in the PVN and PIR of male mice, however, probiotic administration prevented this decrease. The ameliorative effects of probiotics on GR expression are limited to the PVN and PIR and do not extend to the BLA or mPFC. Sex dependant GR expression changes following pubertal stress-programming suggests that sex hormones play a role in stress-management. Furthermore, sex-related differentiation to probiotic administration also suggests that sex hormones interact with the microbiome, or vice versa. Follow-up research may benefit from examining microbiotic changes in relation to sex hormones to obtain a greater understanding of this phenomenon. Using probiotics to reverse the enduring effects of stress programming in the male PVN and PIR illustrates the complexity of gut-brain communication and compels continued investigation of this mechanism.
Caste but Not Sex Differences in the Effects of Social Novelty on Cell Proliferation in a Eusocial Mammal
Troy Collins1, Mariela Faykoo-Martinez1, Matthew Kolisnyk1, Heidi Cheng1, and Melissa Holmes1
1University of Toronto, Ottawa, Ontario, Canada
Changes in the social environment can influence adult neurogenesis in a manipulation- and sex-dependent manner. For example, male hamsters exposed to novel aggressive individuals show increased olfactory bulb neurogenesis, while females do not. Group-housed rats given chronic electric shocks do not have sex differences in new neuron survival. However, socially isolated males display decreased new neuron survival while females display an increase following shock. Naked mole-rats are a eusocial mammalian species notable for large colony sizes dominated by a single breeding female. Subordinate naked mole-rats have increased doublecortin expression in the basolateral amygdala when paired with a novel female, but not a novel male, suggesting a sex-specific increase in threat assessment. Furthermore, female same-sex pairs display less huddling and more shoving than male same-sex pairs, consistent with the competitive matriarchal hierarchy of the species. Here, we examined the effects of exposure to a novel or familiar same-sex naked mole-rat on cell proliferation in neurogenic brain regions. We injected EdU, a marker of cell division, into a sex-balanced groups of adult subordinate soldier and worker naked mole-rats and paired them for 30 minutes with either a familiar or novel same-sex conspecific every 24 hours for 7 days. We then quantified EdU expressing cells in the dentate gyrus (DG), subventricular zone (SVZ), and olfactory bulb. We show that male and female soldiers have higher levels of SVZ cell proliferation than workers. Interestingly, exposure to novel animals decreased cell proliferation in the DG of both sexes. Our findings suggest a caste, but not sex, differentiated response to unfamiliar individuals. Soldiers of this species, regardless of sex, may be more primed to detect odor cues, reflected by a caste-specific difference in proliferation in the SVZ.
Sex Specific Vulnerability to Depression After Chronic Sleep Restriction During Puberty
Michael Murack1, Étienne Malette-Guyon1, Rajini Chandrasegaram2, Zahra Nanji1, Seana Semchishen3, Emily Ah-Yen1, and Nafissa Ismail1
1University of Ottawa, Ottawa, Ontario, Canada
2Cardiff University, Cardiff, Wales, United Kingdom
3Simon Frasier University, Burnaby, British Columbia, Canada
Depression is a prevalent mood disorder responsible for quality of life reduction and, in severe cases, increased suicidal tendencies. Depressive diagnoses escalate in frequency at pubertal onset and exhibits a greater representation in the female populace. Though known to be exacerbated by stressful life events, pubertal onset of depression is still poorly understood. Chronic sleep restriction (CSR) is a stressor common to human pubertal development and is an established symptom of many depressive disorders. Though mechanisms remain elusive, CSR likely influences serotonergic signalling between assembly (dorsal Raphé nuclei) and reception (hippocampus) areas associated with depression. To address this disparity, 80 pubertal and adult CD-1 mice (male, n = 40; female, n = 40) were manually sleep deprived for the first 4 hours of each rest cycle or allowed normal rest for 8 consecutive days. Depressive behaviour was assessed according to the duration and latency to immobility in a Forced Swim test within 12 hours of the final CSR. Brain tissue was treated to examine 5-HT1A receptor expression. Sleep restricted pubertal females and males displayed significantly shorter latency to immobility compared to nonsleep restricted controls. Sleep restricted pubertal female mice also demonstrated greater duration of immobility compared to their adult counterparts. We expect to observe increased and decreased expression in the dorsal Raphé and hippocampus, respectively, after CSR. Sleep restriction during puberty may be a mechanism responsible for the onset of long-term depression in males and females. Achieving appropriately timed sleep in puberty could prevent depressive disorders in adulthood.
Protection From Radiation Induced Neuroanatomical Deficits by CCL2-Deficiency Is Dependent on Sex
A. Elizabeth de Guzman1, Mashal Ahmed1, Stefanie Perrier1, Yu-Qing Li2, C. Shun Wong2, and Brian J. Nieman1
1Mouse Imaging Centre, Hospital for Sick Children, Toronto, Ontario, Canada
2Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
For survivors of pediatric cancer, cranial radiation therapy (CRT) is one of the main contributing factors to neurocognitive deficits. The risk for and severity of these deficits are greater in female patients [1]. Cranial radiation therapy also induces neuroanatomical volume deficits detectable with magnetic resonance imaging (MRI) that are more pronounced in females [2]. While the direct cellular cause remains to be elucidated, chronic inflammation after CRT appears to play an important role [3]. With strong evidence suggesting that sex is an important factor in immune response [4], the goal of this study was to determine how irradiation induced changes in neuroanatomical development (as a proxy for neurocognitive function) depended on inflammatory response, and whether or not that response was modulated by sex. C-C chemokine ligand 2 (CCL2; previously MCP-1) plays a critical role mediating the neuroinflammatory response after irradiation [5]. As a result, we irradiated Ccl2-null (Ccl2-/-) and Ccl2-wild-type (WT) mice with a whole brain dose of either 0 or 7 Gy during infancy. In vivo MRI was used to track brain development for 3 months following irradiation, and deformation-based morphometry was used to identify volume differences across development. Irradiation of WT mice resulted in a deficit in neuroanatomical growth that was largely independent of sex. Ccl2− / − males were significantly protected from this radiation-induced damage, while Ccl2− / − females were not. Interpretation of these results is made in the context of sex- and genotype-dependent brain development in untreated mice. Our study is the first to demonstrate that protection by Ccl2-deficiency after irradiation is dependent on sex. Our conclusions should not be understated: treatments aimed at mitigating neurocognitive deficits by modulating inflammatory response will need to consider patient sex. [1] Précourt, 2002 [2] Nagel, 2004 [3] Monje, 2002 [4] Klein & Flanagan, 2016 [5] Lee, 2012.
Estrogen Mediates Sex Differences in Neuroprotection Against Parkinson’s Disease: A Mechanistic and Behavioral Study
Sara M. Zarate1, Gauri Pandey1, Brittany Cude1, Shannon Storey1, Sunanda Chilukuri1, Jose Andres Garcia1, Taylor Huntington1, Eric Bancroft1, Michelle Hook1, and Rahul Srinivasan1
1Texas A&M Health Science Center College of Medicine, Bryan, Texas, USA
Parkinson’s disease (PD) is a devastating neurodegenerative disease with a 50% greater incidence in men versus women. Parkinson’s disease is characterized by a progressive loss of dopaminergic (DA) neurons in the midbrain which results in motor dysfunction and clinical depression. Treatments for PD are symptomatic, cause severe side effects, and lose efficacy over time, necessitating the discovery of drugs to stop DA neuron loss. Interestingly, chronic tobacco use has been shown to reduce the risk of PD by 50% and our studies have shown that low doses of nicotine (100 nM) attenuate ER stress in DA neurons, which fits with the idea that uncontrolled endoplasmic reticulum (ER) stress contributes to neurodegeneration. We rationalized that nicotine and nicotinic agonists would reduce ER stress via a novel mechanism involving the pharmacological chaperoning of neuronal nicotinic acetylcholine receptors (nAChRs) to the cell surface, resulting in an upregulation of ER exit sites. Therefore, we tested the ability of cytisine, a smoking cessation drug and partial nAChR agonist, to reduce ER stress in mouse primary DA neurons. We found that after exposure to 400 µM 6-hydroxydopamine (6-OHDA), 200 nM cytisine inhibited the activation of 2 key ER stress proteins, ATF6 and XBP1. We then tested the effect of cytisine in a 6-OHDA mouse model of PD and found that alternate day injections of 0.2 mg/kg cytisine attenuated PD-related behavioral deficits only in female mice. Based on these data, we tested if estrogen boosts the ability of cytisine to reduce ER stress in DA neurons. We found that 10 nM β-estradiol inhibited the activation of the pro-apoptotic ER stress protein, CHOP, in the presence of cytisine. We also found that when compared to male mice, cytisine treated female mice showed a 3-fold increase in the number of ER exit sites in midbrain DA neurons. Our data suggest that estrogen exerts a powerful neuroprotective influence in concert with cytisine by increasing ER exit site formation.
Gender Differences in the Microstructure of the Cerebral Cortex
Christie E. MacLeod1 and Nicholas A Bock1
1McMaster University, Hamilton, Ontario, Canada
Researchers have long been interested in how males and females potentially differ in brain structure and function, as well as mental activities, such as cognition, perception, and behaviour. Numerous studies have now reported gender differences in subcortical volume, cortical thickness, functional activity, and performance on certain psychometric tasks. On the contrary, females and males tend to perform similarly on intelligence and neuropsychological tests. In this study, we looked to further characterize gender differences in the human cortex by examining the amount and distribution of intracortical myelin. Like its role in deep white matter, myelin in the cortex speeds the propagation of neural signals and might fine tune the timing of cortical circuits; thus, differences in cortical myelin between males and females may underlie differences in mental activities supported by the cortex. In a large sample of healthy young adults from the Human Connectome Project (N = 1061, F = 580, M = 481; age 29 ± 4 years [mean ± SD]), we used T1-weighted/T2-weighted magnetic resonance imaging (MRI) signal intensity in 360 regions of interest to create cortical maps of myelin density. There was a significant gender effect in 320 regions (P < .05, Bonferroni corrected for multiple comparisons across regions), with males demonstrating higher amounts of intracortical myelin. The were significant age effects in 318 regions and there was no significant age-gender interaction on intracortical myelin levels. While the relationship between intracortical myelin and cortical function is not fully established, these findings might suggest that gender differences in psychology and behaviour between males and females may be explained by differences in brain microstructure. Further, studies are linking intracortical myelin deficits to various neurological diseases, such as bipolar disorder, depression, and schizophrenia, which makes it worth exploring gender effects in these disorders.
Gender Differences in Cardiovascular Diseases in a Cross-Sectional Lebanese Study
Mirna N. Chahine1,2, Rouba K. Zeidan3, Rita Farah4, Pascale Salameh5, and Roland Asmar1,2
1Faculty of Medical Sciences, Lebanese University, Hadath, Lebanon
2Foundation-Medical Research Institutes, F-MRI, Beirut, Lebanon
3Faculty of Public Health 2, Lebanese University, Fanar, Lebanon
4Faculty of Pharmacy, Lebanese University, Hadath, Lebanon
5Institut National de Sante Publique, Epidemiologie Clinique et Toxicologie, Faculty of Public Health 2, Lebanese University, Beirut, Lebanon
Cardiovascular diseases (CVDs) are the leading cause of death in developing countries. Epidemiologic data on gender differences in CVDs is almost inexistent in Lebanon. This study aimed to determine the prevalence and associated risk factors of CVDs according to gender in the Lebanese population. We carried out a cross-sectional study using a multistage cluster sample on individuals aged ≥18 years. Bivariate and multivariate analysis were performed. The latter considered 3 models: (1) sociodemographics characteristics; (2) model 1 and lifestyle factors; (3) model 2 and biological values. We included a total of 2092 participants (1054 [52.44%] women). Our bivariate analysis according to gender showed that 235 (23.6%) men (vs 205 (19.6%) women had at least one CVD (P = .021 for unadjusted gender difference). Multivariate analysis confirmed this result, showing an adjusted OR for female gender ORa = 0.66(0.49; 0.88); P = .004, meaning that women are protected from any CVDs. According to each model, many characteristics and factors may either increase or decrease the risk of developing any CVD, such as: (1) socioeconomic status, marital status, education level in women and body weight, age class, and dwelling region in men or family history in both men and women (model 1); (2) smoking and stress in women and pollution and stress in men (model 2); (3) hypertension in women and hypercholesterolemia and hypertension in men (model 3). In contrast, passive smoking, regular physical activity, and hypertriglyceridemia did not show any protective or worsening effect on the risk of developing any CVD in men or women. This study suggests that CVDs can be attenuated if precise preventive strategies are adopted according to gender. As clinical practice move towards precision medicine, gender differences studies constitute a critical component. Therefore our comprehension of how CVDs progress in each gender independently would lead to a better prevention, diagnosis and treatment of CVDs.
Sex Differences in Ethanol and CRF Effects on Central Amygdala GABAergic Signaling in Alcohol-Dependent and Naïve Rats
Dean Kirson1, Sophia Khom1, Reesha R. Patel1, and Marisa Roberto1
1The Scripps Research Institute, La Jolla, CA, USA
Alcohol dependence, equivalent to moderate to severe alcohol use disorder (AUD), is a chronically relapsing disease characterized by a loss of control over seeking and consumption of alcohol. AUD has been linked to altered functioning of brain stress systems, as chronic alcohol use recruits these systems leading to the negative affective states seen in withdrawal, the relief of which drives further drinking. Both AUD and stress/anxiety disorders have been found to exhibit sex-specific differences among the population. Women are more likely to have an anxiety or mood disorder than men, and men are more likely to abuse alcohol than women. However, women develop addiction more quickly, and are more likely to relapse into repetitive drug use. The central nucleus of the amygdala (CeA) functions as a neuropeptidergic hub of stress and anxiety processing, and GABAergic signaling within the CeA is involved in the regulation of alcohol consumption. We have previously shown dysregulation of GABAergic and stress related peptide systems (eg, corticotropin releasing factor/CRF) in the CeA following the transition to alcohol dependence, but the majority of these previous studies have exclusively used male rats. In this study, we used whole cell patch clamp electrophysiological recordings to examine basal CeA GABAergic spontaneous inhibitory postsynaptic currents (sIPSC) and the effects of alcohol and CRF in both alcohol naïve and chronic intermittent alcohol vapor treated Sprague-Dawley female rats. Basal sIPSC characteristics of frequency, amplitude, and kinetics were not different between naïve males and females, indicating no differences in GABA release or postsynaptic GABAA receptor functions. However, chronic alcohol vapor treatment in females did not increase sIPSC frequency as it does in males. Additionally, acute alcohol (44 mM) had no effect on sIPSC characteristics in naïve or chronic alcohol–treated females, in contrast to the increase in sIPSC frequency we have routinely found in males. These results provide important insight into sex differences in both CeA neuronal functions and changes in this system with alcohol that may contribute to the development of alcohol dependence. This research highlights the potential need for sex specific considerations in the development of novel therapeutics for the effective treatment of AUDs.
AT2R Deficiency Accelerates Renal Dysfunction in Diabetic Progeny in Sex-Dependent Manner
Min-Chun Liao1, Shiao-Ying Chang1, Xin-Ping Zhao1, Chao-Sheng Lo1, Isabelle Chenier1, Julie R. Ingelfinger2, and Shao-Ling Zhang1
1Centre de recherche du Centre Hospitalier de l’Université de Montréal (CRCHUM), Montreal, Quebec, Canada
2Pediatric Nephrology Unit, Mass. General Hospital, Boston, MA, USA
Angiotensin type 2 receptor (AT2R) deficient mice (AT2RKO) exhibit a spectrum of congenital abnormalities of the kidney and urinary tract. We aimed to study whether AT2R deficiency in dams that also had diabetes mellitus would result in offspring with even more abnormalities in the kidney. The offspring (male/female) of nondiabetic and diabetic dams of wild-type (WT) and AT2RKO mice were followed until 20 weeks of age. Systolic blood pressure, insulin sensitivity test (IST), albumin/creatinine ratio (ACR), glomerular filtration rate (GFR), renal morphology, oxidative stress and gene expression including angiotensin converting enzyme (ACE), angiotensin converting enzyme 2 (ACE2), synaptopodin (Synpo) and NADPH oxidase 4 (Nox4) were assessed accordingly. Compared to the age- and sex-matched offspring of nondiabetic and diabetic dams, body weight (BW) differed significantly from each subgroup through life (eg, male > female; AT2RKO > WT mice; and nondiabetic dams’ > diabetic dams’ offspring). Female offspring from diabetic AT2RKO dams developed insulin resistance, while male diabetic progeny of AT2RKO dams had normal IST. As compared to the offspring of nondiabetic dams, diabetic progeny of both WT and AT2RKO mice developed more evidence of nephropathy (higher GFR and apparent glomerulosclerosis with podocyte loss) at 20 weeks of age, which were further aggravated in the offspring of AT2RKO diabetic dams, particularly female mice. Moreover, female offspring of AT2RKO dams had heightened oxidative stress and significant lower basal expression of ACE2/ACE ratio in their glomeruli, and this impaired ACE2/ACE ratio were completely blunted in female progeny of diabetic AT2RKO dams. AT2R deficiency accelerated features of nephropathy in female progeny of diabetic dams, which might be due to loss of the protective effects of ACE2 expression in the kidney.
Sexually Dimorphic Effect of Adult-Pubertal Cohabitation on Acute Immune Responsivity in Mice
Madeleine M. Kearns1, Emma Murray1, and Nafissa Ismail1
1Neuroimmunology, Stress and Endocrinology (NISE) Lab, University of Ottawa, Ottawa, Ontario, Canada
Puberty is a critical period of development that is sensitive to environmental stressors, such as immune challenges. Following exposure to a bacterial mimetic lipopolysaccharide (LPS), mice display age-specific and sex-specific central cytokine expression. Research has suggested that the development of the gut microbiome plays a critical role in the sex and age differences of immune responses in mice. The purpose of this study was to determine if colonization of the microbiome with bacteria from a differently aged mouse can eliminate the age differences in immune responsivity to LPS. Male and female CD-1 mice were cohabitated with same-age (adult-adult, pubertal-pubertal) or differently-aged (adult-pubertal, pubertal-adult) pairs. At 6 (pubertal) or 10 (adult) weeks of age, mice were injected with LPS or saline. Sickness behaviours were monitored at 2, 4, and 8 hours. Mice were euthanized 8 hours after injection. Blood was collected and analyzed using multiplex, to examine serum concentrations of pro- and anti-inflammatory cytokines. Brains were collected and analyzed for cytokine (IL-6, IL-1β, TNFα) mRNA expression with RT-qPCR. In adult males, cohabitation with a pubertal mouse blunted IL-6 and TNFα mRNA expressions in the PFC, IL-6 mRNA expression in the hypothalamus, and IL-1β mRNA expression in the hippocampus (P’s < .05), compared to same-age housed counterparts. Females did not show changes in central immune response across housing conditions. The results suggest that microbiome alterations through differently-aged cohabitation of mice can influence acute immune responsivity. Thus, the age differences observed in immune responsivity may be partly due to housing conditions. These effects are sexually dimorphic and cytokine-specific.
Pharmacogenetics of Methadone Maintenance Treatment and Continued Opioid Use: Sex Differences
Caroul Chawar1, Alannah Hillmer1, Michael Chong2, Amel Lamri3, Lehana Thabane1,2, Flavio Kapczinski3, Guillame Paré2, and Zena Samaan1
1St Joseph’s Healthcare Hamilton, McMaster University, Hamilton, Ontario, Canada
2Population Health Research Institute, McMaster University, Hamilton, Ontario, Canada
3McMaster University, Hamilton, Ontario, Canada
With the rise of the opioid crisis, Opioid Use Disorder (OUD) has become more prevalent in Canada. One of its most common treatments is methadone maintenance treatment (MMT). Methadone metabolism in the human liver is partially regulated by cytochrome P450 enzymes, specifically those encoded by the CYP3A4 gene. The study of CYP3A4 and its associated variants is indicative of methadone metabolism in patients, and possibly treatment outcomes, such as continued opioid use while on MMT. MMT outcomes vary based on patient sociodemographic information, including age, ethnicity and sex. This study aims to analyze sex differences in the effects of CYP3A4-associated variants on continued opioid use. Continued opioid use varies by sex and can be explained by CYP3A4-associated genetic variants. Methods: 574 participants (313 males, 261 females) were selected from the Genetics of Opioid Addiction study. Ten SNPs were selected from NCMI’s SNP database to be studied. Blood samples and urine screens for a 3-month period were used for DNA and opioid use analyses. An additive logistic regression was applied, accounting for age, ethnicity, and sex. The regression was reapplied stratifying by sex. In the adjusted regression, 2 independent SNPs were identified in the population: rs6956344 (OR = 1.036, P = .8712), and rs2246709 (OR = 0.8701, P = .2907). Under sex stratification, rs6956344 (males: OR = 0.9974, P = .9933; females: OR = 1.036, P = .9154) and rs2246709 (males: OR = 0.8419, P = .357; females: OR = 0.8652, P = .4601) associations differed slightly within the sexes. There was no significant association between the selected SNPs and continued opioid use during 3 months of MMT in the total sample. Sex-specific analyses showed no significant associations, but the strength and direction of the associations varied by sex. Larger sample and SNP subsets, imputation, and gender-based analyses could help achieve more accurate results.
Gene × Sex Interactions in A Novel Mouse Model of Alzheimer’s Disease
Kristen M. S. O’Connell1
1The Jackson Laboratory
Age and genetic background are leading risk factors for Alzheimer’s disease (AD), but sex also plays a significant role. Despite clear evidence that the risk and symptomology of AD differs in men and women, few studies of AD in humans stratify based on sex. Similarly, most studies using model organisms such as the mouse tend to use only male animals; even when they do include females, most AD models are made on a single background strain and so fail to incorporate all 3 of the most important risk factors for the human disease. We hypothesize that inclusion of age, sex, and genetic diversity would allow us to discover gene networks and pathways influencing AD risk, including those that are sex-specific. To this end, we developed the first model of genetic diversity in AD—the AD-BXDs—by combining the 5xFAD AD model with the well-established BXD genetic reference panel to create an F1 population harboring causal variants on a background of defined genetic diversity. Cognitive, metabolic, and pathologic phenotypes were assessed across the panel from 2 to 14 months of age. Although age-related increase in amyloid burden in the AD-BXDs was comparable between males and females, female AD-BXD mice were more susceptible to AD-related memory decline compared to male mice, with female mice carrying the ϵ4-like D allele of Apoe displaying more severe decline than those carrying the B allele. As AD is also commonly associated with metabolic dysfunction, we also examined related traits such as weight loss. As in humans, mice carrying causal AD mutations exhibit significantly lower body weights than noncarrier littermates. While both male and female mice exhibited decreased body weights, only in female mice did lower body weight negatively correlate with long-term memory. In genetic mapping studies, we found a significant QTL only in females, suggesting that the underlying genetic susceptibility to AD differs between males and females.
The Impact of DNA Methyltransferase Inhibition on Early-Life Masculinization of Cell Phenotype
Laura R. Cortes1, Carla D. Cisternas1, Ilona Golynker1, and Nancy Forger1
1Georgia State University, Atlanta, GA, USA
There are sex differences in cell phenotype within the hypothalamus; females have many more cells expressing estrogen receptor alpha (ERa) in the ventrolateral region of the ventromedial nucleus of the hypothalamus (VMHvl), while males have more cells expressing calbindin in the sexually dimorphic nucleus of the preoptic area (CALB-SDN). We recently found that neonatal treatment with zebularine, an inhibitor of DNA methylation, increased the number of ERa cells in the VMHvl of males and CALB-SDN cells in females, without altering apoptosis or total cell number. This suggests that DNA methylation is important for sexual differentiation of neuronal cell phenotype. The sex difference in CALB-SDN cell number is due to organizational effects of neonatal testosterone and is present prior to puberty. Here, we tested whether this is also true for ERa expression in the VMHvl and for kisspeptin in the preoptic periventricular nucleus (PeN), and whether an inhibition of DNA methylation at birth would interfere with the masculinizing effects of testosterone. Newborn C57BL/6 female mice received testosterone propionate (T) or peanut oil, sc, as well as intracerebroventricular injections of zebularine or saline on the day of birth (P0) and P1. Mice were sacrificed at weaning (P25) and their brains were collected for immunohistochemical detection of ERa, calbindin, and kisspeptin. As expected, males had more CALB-SDN cells than females, while females had increased ERa cell number in the VMHvl and kisspeptin cell number in PeN. Neonatal testosterone treatment of females completely masculinized all 3 markers. Neonatal zebularine abolished differences between females and T-treated females in the CALB-SDN. Zebularine also increased ERa cell number in the VHMvl of males and T-treated females, but not to the level seen in control females. In contrast, neonatal zebularine had no effect on kisspeptin cell number in any group. This suggests that effects of neonatal testosterone on sexual differentiation of CALB-SDN and ERa are at least partly mediated by DNA methylation, while masculinization of kisspeptin may be independent of DNA methylation. Additionally, our results suggest that inhibiting DNA methylation masculinizes or feminizes depending on the cell phenotype analyzed.
Sex-Specific Effect of Gestational Bisphenols on Fetal Skeletal Muscle and Adipose Tissue Differentiation
Almudena Veiga-Lopez1
1Michigan State University, East Lansing, MI, USA
Increasing evidence supports the notion that the control of energy metabolism differs substantially between men and women, and rates of metabolic diseases have been shown to be sexually dimorphic. Emerging evidence also supports that exposure to endocrine disrupting chemicals (EDCs) can not only alter metabolic responses, but that these responses can also be sex-specific. Bisphenols, one of such class of EDCs, are ubiquitous chemicals used in the manufacture of polycarbonate plastics and epoxy resins and include bisphenol A and S as the 2 most prevalent. Our recent work has demonstrated that prenatal exposure to bisphenols can alter the differentiation ability of fetal cells derived from the mesenchymal stem cell lineage. In particular, our work using a large animal model, focuses on the investigation of EDC-mediated alterations in 2 cell lineages required for maintaining normal insulin to glucose homeostasis and body weight maintenance, namely the adipogenic and the myogenic lineages. Using primary cultured cells after in vivo exposure to bisphenols we have demonstrated that bisphenols can alter the differentiation ability in both these lineages during fetal development. Importantly, we demonstrate that fetal cells derived from a mesenchymal lineage are not only susceptible to programming, but also that these effects are chemical- and sex-specific. Overall, this work begins to pave the way to understand sex differences in metabolic diseases and the role played by environmental exposures.
Post-Conditioning With Acute Estrogen Receptor Activation Improves Functional Recovery Associated with Ischemia-Reperfusion Injury in Mice
Khizer Hafeez1 and W. Glen Pyle1
1University of Guelph, Guelph, Ontario, Canada
Estrogens are proposed mediators of improved cardiovascular health of premenopausal women as compared to age matched men. Recapitulating the cardiovascular benefits with estrogen replacement therapy remains elusive, and the approach is not feasible in men given the broad effects of estrogens. Acute treatment of hearts with estrogen receptor (ER) agonists following myocardial ischemia is a viable way to exploit the cardioprotective effects of ER activation without the negative effects of chronic estrogen exposure. Objectives: Test the ability of acute activation of ER-isoforms to protect hearts of female and male mice subjected to myocardial ischemia. Mouse hearts from both sexes were Langendorff perfused to assess cardiac function (baseline). Hearts were subjected to 20 minute ischemia and 45 minute reperfusion (IR). Damage was assessed by functional recovery after 45 minute reperfusion and molecular and histological markers of damage. ER agonists PPT (ERa) or DPN (ERb) were administered (5 minutes) at reperfusion (postconditioning). Cardioprotection was assessed using percent of baseline LVDP recovered at the end of reperfusion. In hearts from male mice LVDP recovered to 57% of baseline and 61% in females. ERa activation with PPT increased LVDP recovery to 87% in females but had no effect in males. ERb activation with DPN increased LVDP recovery to 73% in females with no significant effect on male recovery. Conclusions: Postconditioning with acute ER activation improves post-IR cardiac function in female mice but not males. Significance: Acute application of ER agonists is a clinically feasible intervention and may reduce the dysfunction of heart attacks, which is a significant health threat to women.
Increased Chromatin Modification Variability and Expression in Immune Cells Characterize the Epigenome in Older Male
Kelly J. McGill1,2, Peggy Cheung1,3, Francesco Vallania1,4, Alex J. Kuo1,3, Sarah E. Chang1,3, Mai Dvorak1,3, Cornelia L. Decker5, Mark M. Davis1,6,7, Paul J. Utz1,3, and Purvesh Khatri1,4
1Institute for Immunity, Transplantation, and Infection, Stanford University School of Medicine, Stanford, CA, USA
2Interdepartmental Program in Immunology, Stanford University School of Medicine, Stanford, CA, USA
3Department of Medicine, Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, CA, USA
4Department of Medicine, Division of Biomedical Informatics Research, Stanford University School of Medicine, Stanford, CA 94305, USA
5Department of Pediatrics, Stanford University School of Medicine, Stanford, CA, USA
6Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, USA
7Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, USA
We previously reported that older adults had markedly increased epigenetic variability compared to younger adults at a single-cell level. Here, we reanalyzed 40 chromatin modifications in 20 immune cell populations in 2 recently published single-cell epigenetic datasets to investigate the effects of the interaction between sex and age on the epigenome. We found 19 significantly more variable chromatin modification-immune cell pairs (FDR < 10%) in older males compared to younger males but not in older females compared to younger females. The top 4 variable chromatin modifications were H3K27me3, H2A119ub, H4K20me2 and H4K5ac. H3K27me3 and H2A119ub are mediated by the Polycomb repressive complexes 1 and 2 (PRC1/2). Dendritic cells, B cells and T cells showed the greatest variability in chromatin modifications. Second, when comparing differences in mean expression, 13 chromatin modification–immune cell pairs had significantly higher expression (FDR < 20%) in older males compared with younger males, whereas no chromatin modification-immune cell pair was significantly different between older females and younger females. Many of the older male-specific chromatin mark—immune cell pairs had both higher variation and higher mean expression of diverse chromatin modifications, including H3K27me3, H2A119ub, H4K20me2, and H4K5ac. In summary, we have discovered that sex alone has a negligible effect both on chromatin modification variation and chromatin modification expression in immune cells. Rather, the interaction of sex and age contributes dominantly to the sex differences we observed at the epigenetic level in healthy adult immune cells. Our findings draw attention to the underappreciated role of sex differences in aging.
Fetal Programming in Maternal Obesity: Sex Differences and the Role of Placental Adiponectin Signaling
Thomas Jansson1, Megan Gossling2, Theresa L. Powell1, Fredrick J. Rosario1, and Owen Vaughan1
1University of Colorado Anschutz Medical Campus
2Masonic Children’s Hospital, University of Minnesota, Minneapolis, MN, USA
Over two-third of American women now enter pregnancy either overweight or obese, which increases the risk for the infant to develop obesity, diabetes and cardiovascular disease in childhood and later in life. However, the underlying mechanisms remain poorly understood. Circulating levels of adiponectin are decreased in obese pregnant women. In our novel mouse model of maternal obesity, which shows extensive similarities with the human condition (low adiponectin, glucose intolerance, activation of placental insulin and mTOR signaling, increased placental nutrient transport and fetal overgrowth), restoration of normal circulating levels of adiponectin completely prevented placental dysfunction, fetal hyperglycemia and overgrowth. However, whether normalization of maternal adiponectin levels in pregnancy attenuates the long-term adverse metabolic and cardiovascular consequences of intrauterine exposure to maternal obesity in the offspring is unknown. We tested the hypothesis that (1) offspring of obese dams develop metabolic and cardiovascular disease, with males more affected than females and (2) adiponectin supplementation in late pregnancy prevents these adverse long-term outcomes. Adult male offspring of obese mice developed obesity, fatty liver, insulin resistance, impaired ventricular diastolic function with increased fetal cardiac gene expression and cardiac insulin/mTOR signaling activity, with female offspring of obese mice having a much less pronounced metabolic and cardiac phenotype at 3 months of age. At 6 months of age, the metabolic and cardiac phenotypes were present in both sexes. These metabolic and cardiac abnormalities in offspring born to obese mice were largely prevented by normalization of maternal adiponectin levels in late pregnancy. We speculate that strategies aimed at improving maternal adiponectin levels may prevent fetal programming of metabolic and cardiovascular disease in offspring of obese mothers.
Sex-Specific Chromatin Organization and Anxiety-Related Phenotypes
Ivana Jaric1, Devin Rocks1, John M. Greally2, Masako Suzuki2, and Marija Kundakovic1
1Fordham University, The Bronx, NY, USA
2Albert Einstein College of Medicine, The Bronx, NY, USA
Anxiety and depression affect around 20% of the world’s population and are 2 times more prevalent in women than in men. Sex-hormone fluctuation is likely the major risk factor for the female’s increased vulnerability, although the mechanism(s) are poorly understood. Sex hormones regulate gene expression via changes in chromatin organization, which remains underexplored in the brain. Moreover, epigenetic mechanisms in the brain have been linked to anxiety-related behavior. We propose that an understanding of how fluctuating sex hormone levels affect chromatin and gene expression in the brain will provide critical insights into the mechanisms underlying sex- and hormone-dependent variation in anxiety-related behaviors. To address this question, we examined female mice in 2 different phases of the estrous cycle: early diestrus (low estrogen-high progesterone) and proestrus (high estrogen-low progesterone), and compared them to males. From 6 to 8 weeks of age, the estrous cycle stage was checked daily by vaginal cytological analysis and hormone levels were later confirmed by measuring estrogen and progesterone levels in serum and the hippocampus. Females placed in diestrus and proestrus groups were examined with age-matched males using 3 anxiety tests: open-field, light-dark box, and elevated-plus maze. Across all tests, female mice in diestrus phase exhibited significantly higher indices of anxiety-like behavior compared to proestrus females and males, implying that a physiological drop in estrogen increases risk for anxiety. To address the underlying mechanism, we assessed the effects of the estrous cycle and sex on neuronal chromatin organization in the ventral hippocampus, an area strongly implicated in anxiety-like behavior. We performed the assay for transposase-accessible chromatin using sequencing (ATAC-seq) on FACS-purified neuronal nuclei isolated from the ventral hippocampus from each of the 3 groups. We show that neuronal chromatin organization significantly fluctuates with the estrous cycle and differs between sexes. In particular, 32.1% of regions showed differential chromatin accessibility between diestrus and proestrus, indicating that hippocampal chromatin undergoes significant reorganization during the estrous cycle. We find changes in chromatin organization associated with the transcriptional activity of nearby genes important for neuronal excitability, neurotransmission, synapse formation, transcriptional regulation, and anxiety behavior. Our findings implicate an estrogen-responsive, immediate early gene product, Egr1, as part of the signaling mechanism mediating estrous cycle-dependent chromatin and transcriptional changes. This study reveals extreme dynamism and sex-specificity of the neuronal epigenome, and helps establish a foundation for the development of sex-specific approaches to treat neuropsychiatric disorders such as anxiety and depression.
Sex Differences in Sensitivity of Hippocampal Neurogenesis to the Stress Hormone Corticosterone
Erin P. Harris1, Martin G. Codagnone1, Lee N. Kavanagh1, Yvonne M. Nolan1, and Olivia F. O’Leary1
1University College Cork
Stress during early life can induce depressive-like behaviours and negatively impact neurogenesis in the hippocampus. Hippocampal neurogenesis is important in buffering the effects of stress and is required for the actions of antidepressant drugs. Many preclinical studies linking hippocampal neurogenesis with stress-related psychiatric disorders have been conducted only in males, which is surprising given that depression is twice as prevalent in women compared to men. Evidence suggests that biological sex may modulate the impact of stress on adult hippocampal neurogenesis, however it is unknown whether these differences are cell-intrinsic or depend on the actions of sex hormones, which become more pronounced after puberty. We aimed to determine whether sex differences in response to the stress hormone corticosterone are apparent in the absence of sex hormones prior to the onset of puberty. Thus, we evaluated the impact of corticosterone on proliferation and differentiation of hippocampal neural progenitor cells (NPCS) derived from prepubertal males and female Sprague-Dawley rats in vitro. Neural progenitor cells were exposed to corticosterone and cultured under proliferation (acute corticosterone exposure, 4 hours) or neuronal differentiation (chronic corticosterone exposure, 7 days) conditions. Corticosterone dose-dependently decreased both cell proliferation and neuronal differentiation compared to the vehicle control. However, the effect of corticosterone was more pronounced in cells derived from males than females. The results suggest an intrinsic sexually dimorphic response of hippocampal NPCs to corticosterone in the absence of circulating sex hormones in vitro. However, it is unclear whether the same trend applies at different developmental stages, such as postpuberty. It remains to be determined how this differential sensitivity to corticosterone relates to behavioural response to stress in vivo and contributes to risk for developing stress-related psychiatric disorders.
Behavioural Effects of Juvenile Stress in Adult Male and Female Rats
Erin P. Harris1 and Olivia F. O’Leary1
1University College Cork
Stress, particularly during childhood, is a major risk factor for the development of major depression, a disorder often comorbid with anxiety. Depression is twice as prevalent in women compared to men suggesting that biological sex also contributes to depression susceptibility. However, the neurobiology underpinning sex differences in the long-term consequences of childhood stress remains unknown. Thus, the aim of this study was to determine the potential utility of a juvenile stress rat model to interrogate sex differences in stress-induced changes in anxiety, anhedonia and antidepressant-like behaviour in adulthood. To this end, male and female Sprague-Dawley rats were exposed to a 3-day stress protocol during the prepubertal juvenile period (postnatal day 27-29) and underwent a battery of behavioural tests in adulthood. In the novelty-induced hypophagia test, a test of anxiety sensitive to chronic antidepressant treatment, juvenile stress decreased latency to approach palatable food in an anxiogenic context irrespective of sex, suggesting either decreased anxiety-like behaviour or increased reward seeking in a risky environment. In the open field test, there was a tendency for stress to increase time spent in the anxiogenic center of the arena for females but not males. In the forced swim test, a measure of antidepressant-like behavior, stress decreased climbing behavior with a concomitant increase in swimming behavior irrespective of sex. We found no significant effects of stress or sex on anhedonia as measured by the saccharin preference test over a period 48 hours. These results suggest that juvenile stress may impact anxiety and antidepressant-like behaviours in adulthood independently of sex, although some sex differences were observed in the absence of stress. Current studies are investigating the potential neurobiological changes underlying these effects including alterations in hippocampal neurogenesis.
Sex Confers Differential Risk for Altered Timing of Behavioral Development That Are Dependent Upon the Form of Early Life Adversity
Camila Demaestri, BS1, Madalyn Critz1, Tracy Pan1, and Kevin Bath, PhD1
1Brown University
Early life adversity (ELA) dramatically increases the risk for developing psychiatric disorders, including anxiety and depression, and is associated with poorer health outcomes. Females have elevated risk for ELA-associated pathology and are twice as likely than males to develop depression and post-traumatic stress disorder. A significant gap in the literature remains with regard to how the specific type and severity of ELA may influences outcomes and contribute to sex-specific risk. ELA can come in many forms, including extreme poverty, hypervigilant parenting, physical abuse, or parental neglect, to name a few. Importantly, these disparate experiences may provide unique signals to the developing organism about the quality of their environment and drive different effects on brain and behavioral development. Understanding the unique consequences of different forms of ELA on neurobehavioral development will be critical for identifying sex-specific risk factors. Here, we compare 2 mouse models of ELA reflecting different forms of adversity with relevance for humans. Specifically, we test the effects of limiting maternal resources or repeated maternal separation on genetic markers of neuronal maturation, somatic and sensory development, and anxiety- and depressive- like phenotypes. We have identified sex-specific effects of ELA, where mice who are subjected to adversity fail to meet typical developmental milestones. We find that the domain of functioning impacted, and the severity of these effects depend upon both up on the form of stress and sex of the developing animal. The current work advances our understanding of what developmental mechanisms are impacted in response to ELA, sex-specific vulnerabilities, and the contribution of each to health outcomes. Such findings may reveal targets for earlier interventions or identification of genetic biomarkers of risk/resilience and provide critical groundwork for individualized medicine.
Reproductive Health in Transgender Individuals
Carl G. Streed Jr, MD, MPH, FACP1
1Center for Transgender Medicine and Surgery, Boston Medical Center, Boston University School of Medicine, Boston, MA, USA
As more than 3-quarters (78%) of transgender individuals desire hormone therapy and nearly half (49%) have received it, understanding its effects is critical. There has been much attention on cardiovascular effects of exogenous hormone therapy in cisgender men and women and more recently transgender women. However, the effects of hormone therapy on reproductive health and best practices for preserving fertility options has not been well discussed. This component of the symposium will discuss best practices in discussing reproductive health concerns for transgender individuals.
Sex Differences in Racial and Ethnic Factors in Cardiovascular Disease Associated With T2D
Rita R. Kalyani1
1Johns Hopkins University School of Medicine, Baltimore, MD, USA
Persons from racial/ethinic minority groups have a higher prevalence of diabetes compared to nonminority populations. Further, cardiovascular diseases are a leading cause of morbidity and mortality among people with diabetes, and disproportionately higher burden is seen among racial and ethnic minority populations with notable sex differences. Understanding CVD risk factors that may be specific to racial and ethnic minorities is therefore crucial to reduce the burden of diabetes and CVD. In general, CVD risk factors such as hypertension, obesity, hypercholesterolemia, physical activity, and smoking differ by sex and there are also disparities by race/ethnicity. Use of preventive therapies such as aspirin also differs by both race/ethnicity and sex. Future CVD prevention programs that are culturally sensitive and recognize sex differences in racial and ethnic factors among persons with diabetes are needed.
Sex and Gender Considerations in Reporting Guidelines Published on EQUATOR Network
Amédé Gogovor1,2, Lionel Adisso1,2, Hervé Tchala Vignon Zomahoun2, Nathalie Rheault2, David Moher3, and France Légaré1,2
1Shared Decision Making, Quebec
2SPOR-SUPPORT UNIT and Laval University
3Ottawa Hospital Research Institute and University of Ottawa
Despite growing recognition of the importance of sex and gender considerations in health research, this is rarely integrated in research design and reporting. We sought to assess the integration of sex and gender considerations in published reporting guidelines. We conducted a review of all published reporting guidelines listed on EQUATOR website (www.equator-nework.org) until December 2018. Inclusion criteria were reporting guidelines (original and extensions) listed on the library of EQUATOR. We used Endnote to build a database of the statement of each guideline identified as “full bibliographic reference” on EQUATOR and retrieved the full texts. Data extracted included: author, year, title, acronym, type of study design that the reporting guidelines apply to as documented on EQUATOR, presence of any of sex and gender related words in the checklist/main text (eg, sex, gender, male, female), and appropriate use of sex and gender based on the Canadian Institutes of Health Research (CIHR) definition of these terms. To assess the integration of sex and gender considerations, we searched for the presence or absence of the keywords “sex” and “gender” in the main text of the statement of the reporting guideline and in the checklist or list of recommendations. We used descriptive statistics to analyze data. A total of 408 reporting guidelines were listed on EQUATOR by December 2018. Based on preliminary results of 371 records, 31% mentioned “sex” and/or “gender” in the checklist and/or explanation text and interchangeably used sex with gender; Of these, 70 (61%) mentioned only “sex,” 50 (44%) only “gender,” and 6 (5%) mentioned both. Of the reporting guidelines that mentioned “sex” and/or “gender”, 6 provided detailed information, for example, Sex and Gender Equity in Research (SAGER). The analysis is ongoing but it appears that integration of sex and gender considerations in reporting guidelines is uncommon and limited to basic mention of the terms.
Sex-Dependent Synaptic and Systemic Metabolic Alterations in 3xTg and 3xTgPOLβ Alzheimer’s Disease Mice
Tyler G. Demarest1,2, Darlene Estrada1,2, Gia T. Truong3, Ruin Moaddell3, Deborah L. Croteau1,2, Mark P. Mattson1,2, and Vilhelm A. Bohr1,2,4
1Laboratory of Molecular Gerontology
2Laboratory of Neurosciences
3Laboratory of Clinical Investigation
4National Institute on Aging, NIH
Alzheimer’s disease (AD) is more prevalent in females than males. Mitochondrial dysfunction and decreased NAD metabolism contribute to AD pathophysiology, but the underlying mechanisms are not well understood. We tested the hypothesis that brain mitochondrial dysfunction is unique in females compared to males, and that altered NAD and systemic metabolism in AD are more severe in females than males. To test this hypothesis, we developed a comprehensive mitochondrial bioenergetics assay in isolated brain mitochondria of synaptic and nonsynaptic origin, allowing for brain-region and cell-type specific analysis of dysfunction within the mitochondrial electron transport chain. We also developed an LC-MS/MS method to quantify NAD metabolism in isolated mitochondria. We used these assays to evaluate 18-month-old male and female littermates in 3xTg and DNA repair-deficient 3xPolβ mouse models of AD. We found that females, but not males, had decreased mitochondrial complex I function in cortical synaptosomes in 3xTg and 3xPolβ compared to WT mice. In nonsynaptic mitochondria, we observed an increase in complex II activity, suggesting increased fatty acid oxidation in astrocytes. We performed unbiased, untargeted plasma metabolomics that confirmed an upregulation of fatty acid metabolism in AD mice, which is more severe in females. In the hippocampus, Polβ heterozygosity resulted in complex I dysfunction in synaptic mitochondria of both sexes. We observed a decline in NAD in synaptic mitochondria, with several NAD metabolites displaying sex-specific changes. Together, these results suggest that mitochondrial dysfunction in the cortex is unique to female AD mice. Consistent with this mouse data, analysis of a human age-matched MRI dataset of late-onset AD patients demonstrated females, but not males, with AD have a decreased cortical volume compared healthy controls. These data suggest that females with AD are prone to cortical mitochondrial dyfunction and neurodegeneration.
Sex-Specific Relationship Between Plasma Sphingosine-1-Phosphate and White Matter Hyperintensities
Michelle M. Mielke1, Jeremy Syrjanen1, Hai Bui2, Ronald C. Petersen1, David S. Knopman1, Clifford Jack Jr1, Jonathan Graff-Radford1, and Prashanthi Vemuri1
1Mayo Clinic
2Eli Lilly
Women have a greater burden of white matter hyperintensities (WMH) than men. Plasma levels of sphingosine-1-phosphate (S1P) have been associated with cardiovascular disease but the relationship between S1P and WMH volume, and potential sex differences, has not been examined. We hypothesized that higher levels of plasma S1P would be associated with a greater WMH volume and that the association would be stronger in women. We cross-sectionally examined this relationship among nondemented participants (284 men and 269 women), aged 60 to 92, enrolled in the population-based Mayo Clinic Study of Aging. Fasting plasma was obtained and S1P was assayed using liquid chromatography electrospray ionization tandem mass spectrometry. FLAIR was used to measure WMH volume, corrected for total intracranial volume. We used linear regression to examine the relationships between plasma S1P and WMH. Both S1P and WMH were log-transformed. In multivariate models adjusting for age, sex, diabetes, and hypertension, S1P was not associated with WMH volume (b (se) = −0.04 (0.12), P = .741). However, there was a significant interaction between sex and S1P (b(se) = −0.73 (0.28), P = .009). Stratifying by sex in multivariate models, higher S1P levels among women (b (se) = 0.28 (0.19)) were associated with a greater WMH volume burden whereas higher levels among men were associated with a reduced burden (b (se) = −0.30 (0.16)). These results suggest that there are sex differences in the relationship between S1P and WMH burden. Longitudinal studies are needed to determine whether plasma S1P is associated with change in WMH volume in a sex-specific manner.
Escape From X-Chromosome Inactivation
Carolyn J. Brown, PhD1,2, Bradley Balaton, BSc1,2, Samantha Peeters, BSc1,2, Andrea J. Korecki, BSc3, and Elizabeth M. Simpson, PhD1,3
1Department of Medical Genetics, University of British Columbia, Vancouver, Canada
2Molecular Epigenetics Group, Life Sciences Institute, University of British Columbia, Vancouver, Canada
3Centre for Molecular Medicine and Therapeutics at BC Children’s Hospital, University of British Columbia, Vancouver, Canada
X-chromosome inactivation (XCI) is the process by which one of the X chromosomes in XX females is silenced, achieving dosage equivalence with XY males. XCI is not complete as 12% of X-linked genes escape XCI in all females and an additional 15% of genes are variable in whether they escape or are subject to XCI. Genes that escape from XCI have expression differences between males and females and therefore may be players in sexually dimorphic disease predispositions. We hypothesize that there are underlying genetic and epigenetic features that allow escape from XCI, and we have approached their identification in 2 ways. (1) We have examined the ability of human genes to be inactivated when integrated as large transgenes (150-200 kb BACs) onto the mouse X. While the majority of human transgenes are silenced on the mouse inactive X, ongoing expression of the human escape gene RPS4X demonstrates that there are intrinsic elements demarcating escape that can be recognized across mammals. Silencing of normally subject genes further suggests retention and recognition of boundary elements between subject and escape regions on the BAC. Using this model, we have shown that escape from inactivation occurs early in development and is stable across the lifespan. (2) Examination of variably escaping genes provides a unique opportunity to compare genes that are subject to, or escape from, XCI in the same genomic context. Determining inactivation status by expressed polymorphisms requires clonal cell populations. We have therefore examined multiomic cancer data sets and a panel of 18 cell lines with skewed XCI to identify variable escape genes and correlate expression with epigenetic marks. We find that the best predictor of inactivation is DNA methylation; followed by H3K9me3, with H3K27me3 showing the most difference across tissues. Variable escapees are intermediate in their methylation patterns, which we have confirmed in TwinsUK published data sets, also identifying a small but consistent genetic contribution. We do not observe domain-level regulation of variable escape from XCI, further implicating promoter-proximal DNA elements allowing expression from the otherwise heterochromatin inactive X.
Sex Hormones and Cardiometabolic Health in Type 2 Diabetes
Kerrie L. Moreau1
1University of Colorado Anschutz Medical Campus, and Geriatric Research Education and Clinical Centers, Veterans Affairs Eastern Colorado Health Care System, Aurora, CO, USA
Although cardiovascular disease (CVD) mortality has been declining in nondiabetic adults, this has not been the case for those with type 2 diabetes (T2D), particular women. In nondiabetic adults, women have a lower prevalence of CVD until mid-life, but then prevalence rates increase rapidly coincident with the menopausal transition to match those observed in men, suggesting beneficial effects of estrogen (E2) in younger women. However, in the context of diabetes, this female advantage is apparently lost. The reasons for this are unclear, but could be related to premature and accelerated vascular aging across the lifespan in T2D women. Vascular aging, featuring endothelial dysfunction, is a critical step in development of atherosclerosis. In general, vascular aging in women is unique because of influences from both chronological and reproductive aging. We and others have shown that in nondiabetic adults, the age-related decline in endothelial function is attenuated in women up until early perimenopause but appears to accelerate during the late perimenopausal and early postmenopausal period due to declines in E2. Estrogen (E2) protects vascular endothelial function by stimulating the synthesis and release of nitric oxide (NO), and by mitigating NO scavenging by oxidative stress and inflammation. T2D may influence ovarian function and reproductive aging over the lifespan; T2D women transition into menopause earlier than nondiabetic women. Additionally, hyperglycemia in T2D may override the beneficial effects of E2 on vascular endothelial function by increasing oxidative stress and inflammation, consequently decreasing NO bioavailability leading to endothelial dysfunction. This presentation will provide an overview of the potential impact of diabetes on the vascular aging process in women, and will discuss areas for investigations to further our understanding of the complex interaction of aging, sex hormones and T2D on vascular function and increased CVD risk in women with T2D.
Predicting Threat: Sex Differences in the Neurobiology of Temporal Fear Learning
Marieke Gilmartin, PhD
1Marquette University, Milwaukee, WI, USA
The ability to anticipate threat is crucial for survival, and cues that signal danger drive adaptive responses to deal with the predicted threat. Learning to link a cue with an aversive outcome is more difficult when the cue and outcome are separated in time (trace conditioning) and requires activity in the prefrontal cortex to maintain a representation of the cue in short-term working memory. We have found that both females and males exhibit this encoding pattern, and yet our recent data reveal that there are sex differences in the underlying mechanisms that support fear memory in the prefrontal cortex. In one study, we found that pharmacological blockade of pituitary adenylate cyclase-activating polypeptide (PACAP) signaling in the prefrontal cortex impairs cued fear learning in females, but not males. This was an intriguing finding given that genetic disruption of the PACAP type 1 receptor has been linked to aberrant fear learning and hyperarousal to threat cues in women, but not men, with PTSD (Ressler et al, 2011). Our data suggest that PACAP signaling in the prefrontal cortex is a critical mediator of its effects on threat-related memory and may provide a neurobiological link to sex differences in PTSD. In a separate study, we tested the contribution of prefrontal muscarinic acetylcholine receptors to fear learning and found that the estrous cycle stage at the time of training gated the effectiveness of scopolamine to impair memory in females. These data show that associative learning in the trace fear paradigm is differentially sensitive to prefrontal neuromodulation in males and females, which points to sex differences in cortical function that nonetheless support the same mnemonic and behavioral end points. Identifying these sex-specific factors is necessary to understand how females and males acquire fear memories as well as determine the neurobiological basis of sex differences in neuropsychiatric disease.
Gender-Based Differences in Cardiology Admissions for Acute Myocardial Infarction
Dalia Giedrimiene, MD, PhD1,2, F. H. Netter, MD3, and Deivydas Giedrimas2,4
1University of Saint Joseph
2Hartford Hospital
3School of Medicine
4Biological Sciences, University of Connecticut
Heart disease (HD) is still a leading cause of death in the United States, and myocardial infarction (MI) has worse prognosis in women than in men. Women with acute MI are more likely to have nonchest pain symptoms, longer delays in seeking medical care. As preventive care options depend on timely diagnosis of HD, interactions with a primary care physician (PCP) are necessary for effective management of risk factors such as cholesterol, blood pressure, diabetes mellitus (DM), and smoking. The aim of this study was to investigate patient access to preventive care provided by their PCP and to assess gender-based differences in patients admitted to the hospital for acute MI. A retrospective chart review was performed for patients admitted to Hartford Hospital via the Emergency Department between August 1, 2016, and April 30, 2018, using the Epic electronic medical record system. Based on inclusion criteria, 234 out of 250 charts were analyzed (mean age 64.65 ± 14.0 years [range 26-89], 62% males). The PCP was documented for 76.9% of patients. A significant difference in age was observed among patients with and without PCP (66.87 ± 15.9 vs 57.24 ± 17.2 [P < .001]). With regard to having a PCP, 84.33% of females and 71.7% of males did (P = .037). Overall, patients without PCP, especially women, were older than patients without PCP. In 80.6% of patients with PCP, the history of hypertension was documented versus 57.4% documented in patients without PCP (P = .001). Smoking cessation, hypertension, hyperlipidemia, and BMI have been identified more often in patients with PCP, and more patients with PCP had treatment for HD, including beta-blockers, statins, anticoagulants, or other medications. Overall, patients with PCP tend to represent older patients with HD, and more older females have a PCP. Patients with PCP more often have a documented history of hypertension, hyperlipidemia, DM, and receive an appropriate treatment.
Escape From X Chromosome Inactivation in Normal Ovarian and Tumor Tissue
Stacey J. Winham1, Nicholas B. Larson1, Melissa C. Larson1, Sebastian M. Armasu1, Julie M. Cunningham1, Simon Gayther2, Kate Lawrenson2, and Ellen L. Goode1
1Mayo Clinic
2Cedars-Sinai Medical Center
X chromosome inactivation (XCI) silences transcription of 1 of the 2 copies in females. However, some genes are known to escape this process and are expressed from both copies, and these escape patterns vary across tissues. Although XCI is specific to females, XCI patterns have not previously been studied in normal ovarian and fallopian tube tissue. We sought to characterize XCI escape patterns in ovarian and fallopian tube tissue, and hypothesize that these patterns may play a role in ovarian cancer (OC). We estimated the probability of escape from XCI for over 300 genes in normal tissue derived from ovarian and fallopian tube surface epithelial cells from 70 patients, as well as tumor tissue samples derived from N = 45 OC patients. We examined the difference in the tumor and normal escape probabilities, and also compared the normal tissue patterns to those previously described for other tissue types. Normal ovarian tissue patterns were similar to published patterns of other tissue types, although 17% of genes showed patterns across individuals of unexpectedly being inactivated in ovarian tissue. Many of these genes have been previously reported as tumor suppressors in ovarian or other cancers (eg, DDX3X and KDM6A). Patterns were strongly correlated between normal ovarian and fallopian tube surface epithelial tissue (R = 0.96). Across 276 genes, 14 genes had significantly different probabilities of escape between tumor and normal samples (P < .00018) and also differed in escape category, with most showing complete inactivation across normal samples but higher probability of escape in the tumor samples (including DDX3X, KDM6A, and RPS4X). Notably, RPS4X was previously associated with poor prognosis in OC, and DDX3X has also been identified as possible drug targets. Additional studies to validate in large samples and to examine somatic changes with paired tumor-normal tissue are needed.
Statistical Methods for X Chromosome Variant Associations: Application to Sex-Specific Characteristics of Bipolar Disorder
William Jons1, Colin Colby1, Sue McElroy2, Mark Frye1, Joanna Biernacka1, and Stacey Winham1
1Mayo Clinic
2Lindner Center of HOPE
Bipolar disorder (BD) is a highly heritable condition affecting 3% of males and females. Many BD characteristics differ by sex. For example, females with BD are at a greater risk of rapid cycling and are more likely to engage in binge-eating behavior. Few studies have explored the role of the X chromosome in BD, which is complicated by X chromosome inactivation (XCI), an epigenetic process that silences 1 of the 2 copies of the X chromosome in females. Most statistical methods either ignore that XCI occurs, or falsely assume that all variants are inactivated (10%-15% of genes escape from XCI). We hypothesize that X chromosome variants may be associated with sex-specific characteristics of BD. We investigated this hypothesis in 1001 BD patients from the Genetic Association Information Network (GAIN) and 957 BD patients from the Mayo Clinic Bipolar Disorder Biobank. We examined the association of over 14 000 X chromosome single nucleotide polymorphisms (SNPs) with sex-associated BD traits using 2 statistical approaches that account for whether a SNP may be undergoing or escaping XCI. In the first approach (“combined approach”), we fit a logistic regression model assuming additive genetic effects and adjusted for sex, where we coded the SNP either assuming one copy is expressed or 2 copies are expressed, depending on prior knowledge about which regions are inactivated. In the second approach (“interaction approach’), we fit a logistic regression model with a sex, SNP, and SNP-sex interaction effect that is flexible to whether the region is inactivated or escaping XCI. Both approaches were applied to both data sets and the results were meta-analyzed. No SNPs were significant after multiple testing correction in the “combined approach.” Using the “interaction” approach, intergenic SNP rs5932307 was associated with BD (P = 1.1 E− 7), with a stronger effect in females (ORM = 1.13, ORF = 1.97). Further work should validate these findings in larger sample sizes.
X-Chromosome Inactivation, Mosaicism and the Placenta
Wendy P. Robinson1, Amy Inkster1, Maria S. Peñaherrera1, Giulia F. Del Gobbo1, and Carolyn J. Brown1
1University of British Columbia and BC Children’s Hospital Research, Vancouver, British Columbia, Canada
Many sex differences exist during in utero development that likely have their origins in the placenta. In general, presence of a male fetus is associated with increased risk of adverse outcomes including stillbirth, neonatal death, preterm birth, and fetal growth restriction. In contrast, we find that chromosomal mosaicism and chimerism in the placenta is more common in female as compared to male conceptuses. This bias suggests a greater male lethality of mosaic embryos at the pre- or peri-implantation stage. At the most basic level, males and females differ only by their sex-chromosome complement. As the process of X-chromosome inactivation (XCI) is not initiated until the late blastocyst stage, there is a dosage imbalance of most X-linked genes up to this point. Furthermore, some genes escape XCI altogether, and there may be more escape of XCI in the placenta since the inactive X chromosome is relatively hypomethylated in female placenta as compared to other tissues. We hypothesize that sex differences in perinatal health arise from (i) more escape of XCI in the placenta, which reduces interplacental differences in females as compared to males; (ii) mosaicism for XCI leading to greater intraplacental diversity in the female placenta. This intraplacental diversity may help the female placenta to adapt to adverse conditions. We are currently exploring the unique nature of the DNA methylation on the X chromosome in placenta using Illumina genome-wide DNA methylation arrays, combined with other approaches, and examining how these features might contribute to sex-differences in perinatal outcomes.
The Sexually Dimorphic Response of Genetically Heterogeneous Mice to Lifespan-Extending Drugs Varies With Chronological Age
Catherine C. Cheng1, Jonathan A. L. Gelfond1, Randy Strong1, and James F. Nelson1
1University of Texas Health San Antonio, San Antonio, TX, USA
The NIA Interventions Testing Program has discovered 6 drugs that extend lifespan in genetically heterogeneous UM-HET3 mice. This is the first mouse model that mimics the sexual dimorphism in human mortality: namely, a female survival advantage that is largely the consequence of higher male mortality during early-to-mid adulthood (Cheng et al, Aging Cell, 2019). Only one of the 6 drugs extends lifespan more in females than in males. Four of the other drugs are only effective in males and one is more effective in males. Understanding the basis for this sexual dimorphism in drug efficacy is important both for elucidating the mechanisms of healthy aging and for developing therapies that are effective in both sexes. Our earlier finding that higher male mortality in untreated mice is limited to the period before midlife coupled with the fact that male-specific drugs usually only improve survival up to, but not beyond, that of untreated females led us to hypothesize that the male-specific drugs improve survival by only reducing the mortality hazard before midlife. We therefore reexamined the mortality data, which previously had only been analyzed by log-rank analysis, using a Cox model with age-specific treatment effects. The mortality data were subdivided according to age tertiles—young, middle-aged, and old—each with equal numbers of deaths. As hypothesized, 3 of the 4 male-specific drugs only reduced the mortality hazard during the period of higher male mortality that occurs in untreated mice (ie, during the young and/or middle aged tertiles). The fourth drug gave the same result at the lowest dose administered, but at a higher dose also reduced mortality in the oldest tertile, albeit to a lesser extent. These age-specific analyses reveal that the male bias of life span-extending drugs so far identified is largely associated with a selective reduction in the early/midlife mortality excess in males and not due to any effect on late life mortality.
Gender Differences in the Acute Effects of Cannabinoids in Humans
Maria J. Orejarena1,2, Christina Luddy1, Brian Pittman1, Deepak C. D’Souza1,2, Patrick Skosnik1,2, and Mohini Ranganathan1,2
1Yale University
2VACHS
Rates of cannabis use have been rapidly increasing in women. Further, once initiated, women develop CUD more rapidly than men with worse outcomes. Results from human studies on gender-related differences in cannabis effects have been mixed, possibly due to issues of tolerance (in heavy cannabis users), lack of objective measures and known differences in bioavailability and pharmacokinetics (Pk) with oral and inhaled administration. We present data comparing the acute dose related effects of intravenous THC in men and women with infrequent cannabis exposure, thus avoiding these confounds related to dose, route of administration, pharmacokinetics and cannabis use histories.
Sex Differences in Transplacental Signals
Tracy L. Bale1, Carly O’Donnell1, and Bridget Nugent1
1Department of Pharmacology and Center for Epigenetic Research in Child Health and Brain Development, University of Maryland School of Medicine, Baltimore, MD, USA
Parental lifetime exposures to perturbations such as stress, infection, malnutrition, and advanced age have been linked with an increased risk for offspring disease, including a strong association with neurodevelopmental disorders. In our mouse model of early prenatal stress (EPS), stress exposure during the first week of gestation imparts long-term developmental programming deficits in male, but not female, offspring resulting in hypersensitivity to stress, cognitive impairments, and alterations in metabolic programming, effects that can be passed from father to son. The placenta, a fetally-derived tissue reflecting fetal sex chromosome complement, acts as an arbitrator between the mother and fetus, providing necessary factors for early fetal neurodevelopment. We identified the X-linked, stress sensitive, nutrient sensor O-linked-N-acetylglucosamine (OGT) as a placental biomarker of prenatal stress. Genetic placental-specific reduction of OGT recapitulates the developmental and metabolic impairments associated with our mouse model. We found that OGT determines genome-wide sex differences in H3K27me3 and gene expression in placental trophoblasts. Placental-specific reduction of OGT recapitulates our EPS phenotype. Using ChIP-Seq, biochemistry, and RNA-Seq in mouse placentas with trophoblast-specific OGT reduction, we found that OGT determines genome-wide sex differences in H3K27me3 and gene expression in placental trophoblasts. Further, RNA-Seq of the embryonic hypothalamus revealed that reducing OGT in the female placenta masculinized the expression of key genes associated with hypothalamic development, suggesting that placental OGT contributes to sex differences in brain development. Overall, these studies demonstrate that parental life experiences can induce germ cell epigenetic reprogramming and impact offspring neurodevelopment, and may therefore offer novel insight into factors influencing disease risk. Studies were funded by NIMH, NICHD, and NIEHS.
Beyond “Better” Or “Worse”: Sex Differences in Strategies Engaged During Fear Conditioning
Natalie C. Tronson, PhD1
1Psychology Department, University of Michigan, Ann Arbor, MI, USA
There is a long history of studying the behavioral processes, cognitive strategies, neural circuits, and molecular mechanisms underlying learning and memory. As such, we have a strong basis for understanding how memory works—at least in males. Recent work has begun to identify where males and females differ in performance and in molecular mechanisms of memory tasks. Yet it is also becoming clear that sex differences in memory tasks may be due to alternative behavioral or cognitive strategies engaged during training or test. For example, females show greater generalization of context fear conditioning, showing more freezing than males to a context similar to, but distinct from the training context. Based on data from males, generalization is often interpreted as a failure to learn a detailed context representation. Alternatively, generalization to a similar context may be a risk-avoidant strategy in the face of an ambiguous relationship to danger—not a failure to learn but the use of slightly different strategies in response to a similar situation. Support for this possibility comes from data demonstrating that females also show overlapping but distinct recruitment of brain regions and molecular mechanisms critical for memory formation and retrieval, suggesting engagement of different neural circuits, cognitive processes, and behavioral strategies. Together, these findings suggest that rather than failing to efficiently learn context fear conditioning, females are better viewed as using overlapping but distinct cognitive and behavioral strategies, circuit and molecular mechanisms. Here, we suggest that sex differences in memory can be effectively conceptualized within a multiple memory systems framework in which memory systems are dynamic and flexible, and memory tasks can be solved in a variety of ways, depending on available information, internal state, and biological sex of the animal.
Developmental Disruption of Locus Coeruleus-Norepinephrine Signaling Results in Male-Specific Behavioral Phenotypes Relevant to Neurodevelopmental Disorders
Irina Evsyukova1, Nicholas W. Plummer1, Jemma M. Strauss1, Kathleen G. Smith1, Natallia Riddick2, Sheryl S. Moy2, Jesse D. Cushman1, and Patricia Jensen1
1National Institute of Environmental Health Sciences
2University of North Carolina at Chapel Hill
Neurodevelopmental disorders are characterized by impaired social communication and learning which are known to be modulated by locus coeruleus norepinephrine (LC-NE) signaling to hippocampus and medial prefrontal cortex. While it has previously been proposed that developmental dysregulation of the LC-NE system leads to behavioral deficits associated with neurodevelopmental disorders, evidence supporting this hypothesis is lacking, primarily due to the inability to selectively target the LC early in development. To circumvent this problem, we exploited the fact that LC-NE neurons are uniquely defined by embryonic expression of the transcription factor Engrailed 1 (En1) and later expression of dopamine β-hydroxylase (Dbh) which is required to convert dopamine to norepinephrine. To specifically target the LC early in development, we generated a conditional knockout allele of Dbh (Dbh cko) and crossed it with En1cre (LC-NE mutants). Unlike the full Dbh knockout, which is embryonic lethal, conditional LC-NE mutants survive to adulthood, allowing us to evaluate the consequences of embryonic disruption of LC-NE on adult behaviors. We observed reduced sociability, deficits in contextual learning, hyperactivity, and increased incidence of seizures in male LC-NE mutants. In addition, we investigated whether dopamine is elevated in the cortex of adult LC-NE mutants as a consequence of Dbh loss. Surprisingly, dopamine was elevated in female mutants but unchanged in males, relative to littermate controls. These data suggest that the behavioral phenotypes observed in male LC-NE mutants are likely due to loss of NE, rather than increased dopamine, and that elevated dopamine may compensate for NE loss in females. Together, these findings suggest that embryonic disruption of LC-NE signaling has selective, sex-specific effects on multiple forebrain targets, resulting in behavioral deficits associated with neurodevelopmental disorders.
Social Stress Produces Age- and Sex-Dependent Changes in Prefrontal Cortical Neuronal Activity and Morphology
Kimberly R. Urban1, Eric Geng2, Seema Bhatnagar1,2, and Rita Valentino3
1Children’s Hospital of Philadelphia
2University of Pennsylvania
3NIDA
Chronic stress can lead to psychiatric illness characterized by impairments of executive function, implicating the prefrontal cortex (PFC). Many studies have shown impairments in PFC function and dendritic retraction following various stressors in adult males; however, little is known about age-dependent or sex-specific effects. Because the PFC develops throughout adolescence, stress during this period may have a greater impact on than stress occurring during adulthood. Furthermore, females display greater risk of stress-related psychiatric disorders, indicating sex-specific responses to stress. In this study, early adolescent (32-38 days old), mid-adolescent (42-48 days old), or adult (68-72 days old) male and female Sprague-Dawley rats were exposed to 5 days of resident-intruder stress or control manipulation. Twenty-four hours after the final defeat, 300 µM brain slices were obtained and layer 5 pyramidal neurons in the PFC were recorded using whole-cell patch clamp. Neuronal excitability evoked by high current intensities was decreased in stressed male and female mid-adolescent rats, whereas neuronal excitability elicited by low current intensities was selectively increased in stressed male midadolescent rats. Social stress generally decreased synaptic excitability as measured by the amplitude of spontaneous excitatory postsynaptic potentials, although these effects were most prominent in females. Additional brains were Golgi stained 24 hours after the final manipulation, viewed using a Nikon Eclipse, and Neurolucida was used to reconstruct pyramidal neurons and analyze dendrites in layers II/III and V. In layer II/III, stress-reduced apical dendritic branching in male and female adolescents and basal dendritic branching of adult males. In layer V, stress increased apical branching in adult males and decreased it in all other groups. Branching of layer V basal dendrites was selectively increased in adult male rats. These results suggest that repeated social stress particularly during midadolescence reduces PFC neuronal complexity and function, which may result in impairments in executive function and PFC-dependent cognition. These changes extend into adulthood for females but not males. That resident-intruder stress had the unique ability to increase mPFC dendritic complexity of adult males with no effect on neuronal function implies that this experience is perceived differently by this population and suggests that the experience of fighting for dominance may selectively enhance cognitive processing for this group.
Sex Differences in Mortality in a Novel Adult-Onset SUDEP Mouse Model
Cory A. Massey1 and Jeffrey L. Noebels1
1Baylor College of Medicine, Houston, TX, USA
Sudden Unexpected Death in Epilepsy (SUDEP) is a leading cause of mortality in patients with epilepsy and is estimated to be the cause of death in up to 17% of this population. Previous studies report that mice lacking the 5-HT2C receptor die prematurely and some deaths were witnessed following a generalized tonic-clonic seizure (GTCS), but the epileptic profile of these mice remains poorly understood. We implanted 5-HT2C mutant and wild-type (WT) littermates for electroencephalogram (EEG) recordings with silver-wire leads bilaterally over frontal and parietal cortex and 2 reference electrodes over the olfactory bulbs as previously described in our laboratory. We observed that 39.18% of our male 5-HT2C-null mice (29/74) died prematurely compared to only 1.20% of male WT mice (1/83). However, premature mortality was not as high in female 5-HT2C mutant mice. We observed premature death in 5.80% of female heterozygous (4/69) and 9.52% of female homozygous (6/63) compared with 5.26% of female WT mice (1/19). We also observed 5-HT2C mutant mice had 3 different spontaneous seizure phenotypes: spike-wave discharges (SWDs) that were similar to seizures seen in absence epileptic mouse models, generalized nonconvulsive seizures, and GTCS. In addition, we could induce audiogenic seizures in 5-HT2C mutant mice. These data demonstrate that 5-HT2C mutant mice have a novel SUDEP phenotype that is adult-onset, as opposed to current genetic SUDEP models which have a high mortality rate in the first few weeks of life. 5-HT2C mutant mice have a complex epileptic phenotype with at least 4 different seizures observed. Finally, we discovered that there are sex differences in SUDEP mortality rates in 5-HT2C mutant mice, which is a novel finding for a SUDEP mouse model. Further experiments will investigate the role of 5-HT2C receptors in forebrain and brainstem excitability and describe underlying mechanisms that decrease SUDEP incidence in female 5-HT2C mutant mice.
Bilateral Salpingo-Oophorectomy Prior to Spontaneous Menopause Is Associated With Reduced Right Frontal Cortical Thickness and Working Memory Performance: A Protective Role for Hormone Therapy
Anne Almey1,2, Nicole Gervais1, Annie Duchesne3, Rebekah Reuben1, Laura Gravelsins1, Elizabeth Baker-Sullivan1, Suzanne T. Witt4, Åsa Rydmark Kersley5, Elisabet Classon6, Jan Ernerudh6, Elisabeth Åvall Lundqvist7, Preben Kjölhede5, Elvar Theodorsson6,8, Giovanni Novembre6, Maria Engstrom9, Nina Lykke10, Cecilia Åsberg10, William Foulkes11, Wendy Meschino12, Marcus Bernardini13, Andrea Eisen14, Cheryl Grady15, Natasha Rajah2, and Gillian Einstein1,4
1Psychology, University of Toronto
2Psychology, McGill University
3Psychology, University Northern British Columbia
4CMIV, Linköping University
5Obstetrics and Gynecology, Linköping University
6Clinical and Experimental Medicine, Linköping University
7Clinical Oncology, Linköping University
8Clinical Chemistry, Linköping University India Morrison
9Medical and Health Sciences, Linköping University
10Gender Studies, Linköping University
11Medicine, McGill University
12Pediatrics, University of Toronto
13Obstetrics and Gynecology, University of Toronto
14Medical Oncology, Sunnybrooke Health Sciences Center
15Rotman Resesarch Institute, University of Toronto
Loss of ovarian hormones following spontaneous or surgical menopause is implicated in the elevated incidence of Alzheimer’s in women (Rocca et al, 2007; Zeydan et al, 2018), but it remains unclear how loss of ovarian hormones contributes to cognitive decline. Evidence suggests loss of estrogens leads to decreased hippocampal volume and function (Duchesne et al, 2017; Eberling et al, 2004; Zeydan et al, 2018), but research on the cortex is scarce. To investigate this, we compared structural scans of BRCA-mutated women with bilateral salpingo-oophorectomy prior to spontaneous menopause (BSO) to those of healthy age matched controls (AMC). We asked if early loss of ovarian hormones affects cortical thickness or performance on working memory tasks. Women in this study were divided into 3 groups: BSO no hormone therapy (HT; BSO-HT, n = 22), BSO on HT (BSO+HT, n = 20), and AMC (n = 42). Participants completed neurocognitive tests and an MRI scan. Scores on working memory tasks were compared between groups using a bootstrap approach with a General Linear Model (GLM). T1-weighted structural images were analyzed using the CIVET 2.1 pipeline to obtain cortical thickness, and a GLM (SurfStat, MATLAB) was used to examine both the main effect of surgery (BSO vs AMC) and age*surgery interaction. The BSO-HT group performed significantly worse than AMCs on one working memory task, digit span backwards, while BSO+HT participants did not differ from AMCs. Correspondingly, the BSO group had a significantly thinner right lateral frontal and temporal cortices than AMCs; this effect that was driven by BSO-HT as BSO+HT did not differ from AMCs. These findings suggest decreased working memory performance and cortical thickness following BSO, which is not observed if HT is taken. Since working memory depends, in part, on the prefrontal cortices (Kane & Engle, 2002), the thinning of the right frontal cortex may contribute to the poorer performance on tests of attention and working memory.
Mapping the Mouse Brain: An Investigation of Dopamine Circuitry
Justin Buck1, Ted B. Usdin2, Erica R. Glasper1, and Kuan Hong Wang2,3
1University of Maryland, College Park, MD, USA
2National Institute of Mental Health
3University of Rochester, Rochester, NY, USA
Throughout development, dopamine circuit architecture undergoes substantial changes as a result of preprogrammed chemical cues and experience-dependent plasticity. Experiences that are rewarding during adulthood have been shown to alter dopamine synapses in the prefrontal cortex, nucleus accumbens, and basal ganglia. Additionally, disruptions in dopamine axon growth and synapse formation in the prefrontal cortex have been associated with a variety of neurodevelopmental disorders. Due to the wide distribution of dopamine axon connections throughout the brain, large-scale volumetric evaluations are necessary to understand the mechanisms of these phenomena and their functional implications. However, the efficacy and speed of traditional imaging and tissue processing techniques have limited whole brain analyses and largely prevented comprehensive circuit comparisons. By coupling the X-CLARITY tissue clearing method with light sheet fluorescence microscopy, we are rapidly acquired whole-brain reference maps of dopamine circuitry in both sexes at 3 stages in development in Mus musculus. Age- and sex-specific differences in the distribution and prevalence of dopamine neurons will be examined. These maps will also be used as a reference when investigating models of neuropsychiatric disorders such as schizophrenia. Additionally, we are developing the first maps, to our knowledge, of dopamine circuitry in both sexes in the monogamous mouse species Peromyscus californicus. These maps will help us better understand neural sex differences and the impact of parental behavior on dopamine neuroanatomy.
Association Between Stress Reactivity and Hormonal Contraceptive Use
Taylor B. Irvine1 and Peter L. Hurd1
1University of Alberta, Edmonton, Alberta, Canada
Previous findings support the observation that hormonal contraceptive (HC) use may be linked to changes with stress reactivity and cortisol levels. There are known sex differences with regard to stress reactivity where men typically have increased salivary cortisol after stress tasks. We hypothesize that HC users will have increased stress response compared to women who do not use HC and that their cortisol levels will more closely resemble that of men. To test our hypothesis, we recruited 100 female participants using an undergraduate research participant pool. Participants completed a questionnaire that determined their phase in their menstrual cycle and HC use. The questionnaire also assessed their daily stress as well as their stress after a mental arithmetic task. The mental arithmetic task consisted of mentally performing serial subtractions of 7 from a starting from 986, and participants gave the answers aloud. Subjects were told that both speed and accuracy were important, and that if they make a mistake, they must start over from 986. Lastly, saliva was collected and salivary cortisol levels were measured. We examined associations between HC use, stress, and cortisol levels. Increasing our knowledge of how HC usage may interact with an individual’s behaviours and cognition is critical for informing women on potential effects of HC use as well as potentially developing more modernized forms of HC that do not alter female behaviour and cognition.
Sex-Specific Effects of Allelic Gene Regulation by KDM6A
Joel B. Berletch, PhD1, Wenxiu Ma, PhD2, He Fang1, Galina N. Filippova1, and Christine M. Disteche, PhD1,3
1Department of Pathology, University of Washington
2University of California, Riverside
3Department of Medicine, University of Washington
The KDM6A protein demethylates the repressive histone mark H3K27me3 and thus plays an important role in developmental gene regulation. KDM6A levels are female biased because the Kdm6a gene escapes from X inactivation, suggesting that this protein may play a role in sex differences. Here, we report that maternal and paternal alleles of a subset of mouse genes are differentially regulated by KDM6A. Knockouts of KDM6A in male and female embryonic stem cells derived from F1 hybrid mice result in preferential downregulation of maternal alleles of a number of genes implicated in development, whereas upregulated genes show no allelic preference. A subset of maternally expressed imprinted genes expressed in ovary or placenta—the Meg3-Rian cluster, the Xlr cluster and Phlda2—are dependent on KDM6A for expression. Downregulated maternal but not paternal alleles demonstrate a loss of chromatin accessibility, but without the expected changes in H3K27me3 levels, which increase only on downregulated paternal alleles. These results illustrate a novel type of allele-specific regulation of genes expressed in sex-specific tissues. We also found that parent-of-origin mechanisms of gene regulation by KDM6A were consistent with both histone demethylation-dependent and -independent effects. Our results indicate that KDM6A plays an important role in gene expression regulation during development in a sex-specific manner.
Sex Differences in Immunity to Influenza Vaccine in the Elderly
Helen Kuo1, Rosemary Morgan1, Abdul Bachani1, Sabra Klein1, and Sean Leng2
1School of Public Health, Johns Hopkins Bloomberg, Baltimore, MD, USA
2School of Medicine, Johns Hopkins University, Baltimore, MD, USA
Influenza is a top challenge to aging immunity and health with the highest burden of severe disease and complications affecting older adults. We hypothesize that there are biological sex differences among older adults in immunity to the flu vaccine due to immunological and hormonal factors contributing to sex-specific vaccine-induced immunity and outcomes. Currently, this is an unexplored area as most studies only report enrollment of both sexes and do not disaggregate or analyze dependent measures for sex differences across age ranges. An ongoing flu vaccine study started in the 2014-2015 season recruited 450 community-dwelling older adults aged over 75 years in Baltimore, Maryland. Study participants were recruited from outpatient clinics, informed consent was obtained during a prevaccination visit, a comorbidities questionnaire was administered, and whole blood was collected at the time of the baseline visit and vaccine administration. Seven and 28 days following the baseline visit, additional whole blood was collected. The number of subjects who completed the entire flu season with pre- and postvaccination blood samples and data for postvaccination flu surveillance were 72, 94, 112, and 172 for 2014-2015, 2015-2016, 2016-2017, and 2017-2018 flu seasons, respectively, of which 196 (43.6%) were male. There were 125 subjects who participated in at least 2 seasons (54 males, 43.2%) and 34 subjects who participated in all 4 seasons (15 males, 44.1%). Preliminary analysis of the HI titer data obtained in 2015-2016 flu season from subjects who participated in at least 2 out of the 4 seasons indicates significant sex differences related to rates of seroconversion (post/prevaccination >4 fold) (ie, immunal response to the vaccine). Out of 94 subjects who participated in the 2015-2016 flu season, 27 (19 females, 8 males) seroconverted to H1N1, 57 (39 females, 18 males) to H3N2, and 23 (17 females, 6 males) to B strain. This indicates that females were more likely to seroconvert to all vaccine flu strains than males. The observed sex differences also appeared to vary among vaccine strains. Future research will explore whether these sex differences are significant while accounting for fragility, age, and race.
Differential Modulation of Diabetes by Androgens and Estrogens in Males and Females
Franck Mauvais-Jarvis1
1Tulane University School of Medicine and Southeast Louisiana Veterans Affairs Medical Center, New Orleans, LA, USA
One of the most sexually dimorphic aspects of metabolic regulation is the bidirectional modulation of glucose homeostasis by testosterone in male and females. Testosterone deficiency predisposes men to diabetes, while in contrast, its androgen excess that predisposes women to hyperglycemia. I will discuss recent evidence that the androgen receptor (AR) is present in male and female pancreatic insulin-producing β cells. In males, testosterone action on AR in β cells enhances insulin secretion and prevents diabetes. In females, excess testosterone action via AR in β cells promotes insulin hypersecretion leading to oxidative injury, which in turn predisposes to diabetes. Estrogens favor glucose homeostasis primarily through the estrogen receptor-α (ERα) in males and females. Recent evidence from our lab suggests that lack of ERα alters the central control of insulin sensitivity in females, while in contrast, it predominantly impairs the central regulation of insulin secretion in males.
Relevance of Gender in the Drug-Utilization Pattern of Non Small Cell Lung Cancer patients at University Hospital of Siena, Italy (UHS)
Andrea Spini1, Marina Ziche1, Giuseppe Roberto2, Rosa Gini2, Agenzia Regionale di Sanità Toscana2, Florence Valerio Ciccone2, Sandra Donnini2, Alessandra Pascucci, Pietro Rosellini3, Edoardo Francini4
1Department of Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy
2Department of Life Sciences, University of Siena, Siena, Italy
3University Hospital of Siena, Siena, Italy
4University “La Sapienza”, Rome, Italy
Lung cancer is the third most commonly occurring cancer in females. NSCLC represents about 85% of all cases of lung cancer. Recently, treatment guidelines for NSCLC have changed due to the introduction of new drugs for patients with advanced stage disease. The aim of the study was to analyze the treatment patterns of patients diagnosed with NSCLC in advanced stage between 2009 and 2017 at the University Hospital of Siena (UHS), focusing on gender difference in drug utilization. Patients with NSCLC diagnosis were identified by records in the pathology registry (PR) of UHS between January 2009 and June 2017. PR data of NSCLC patients were anonymized and linked to the administrative healthcare database of Tuscany region. Advanced stage patients were defined as those without surgical intervention (NO-SUR patients). A total of 2003 NSCLC patients were identified. There was a statistically significant upward trend (P = .0177) in the incidence in women, rising from 25% in 2009 to 38% in 2017. The average age of patients was 69 years and 45.3% were aged between 50 and 69 years. NO-SUR were the 57.1% of the study cohort (n = 1144). This cohort was divided in elderly, aged ≥70 years (n = 587), and young patients, aged 18 to 69 years (n = 557). In the 6 months following the index date, the percentage of subjects who received both immunotherapy and target therapy was higher among young patients, 5.9% versus 1.7% and 13.1% versus 11.1%, respectively and increased from 2.8% to 28.2% in young patients (P < .001) and from 1.4% to 6.9% in elderly patients between 2015 and 2017. In this cohort, the proportion of women increased. Data will be presented on the pattern of drug utilization and outcome in relation to gender. Real-world data on the pattern of drug utilization provide important information for clinician and health provider both in terms of appropriateness and economic sustainability of cares. The Battle of the Sexes: Androgens and Estrogens in Control of White Adipose Tissue Metabolism
Annie E. Newell-Fugate1
1Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA
In the United States, the obesity rate of men (35%) has plateaued, but the obesity rate of women (40%) continues to increase. In recent years, sex steroids have been shown to play a critical role in a variety of obesity-associated diseases like hypertension and type 2 diabetes (T2D). While estradiol (E2) stimulates subcutaneous (SC) lipogenesis and contributes to a gynecoid white adipose tissue (WAT) distribution, the role of testosterone (T) in WAT metabolism is less clear. Obese men have low T serum concentrations but have variable E2 serum concentrations and an increased risk for T2D. Conversely, women with polycystic ovary syndrome have high serum T concentrations and are at risk for increased visceral white adipose tissue (VWAT) deposition and insulin resistance irrespective of serum E2 concentrations. Furthermore, the cellular mechanisms by which sex steroids control adipocyte insulin signaling, lipogenesis, and lipolysis in males and females are poorly characterized. Our lab has utilized in vivo and in vitro swine and rodent models to explore the role of local androgens and estrogens, their respective receptors, and steroidogenic converting enzymes on WAT insulin signaling and metabolism. We have demonstrated that, dependent on ERa:ERb, T differentially regulates adipocyte insulin signaling at the level of protein kinase B and forkhead box protein 1 in males and females. This androgenic regulation of insulin signaling is dependent not only on ERa:ERb but also on local adipocyte aromatase function and transcript expression. The VWAT is more sensitive to the effects of androgens on basal lipogenesis and the insulin signaling cascade than the SCWAT. More interestingly, T suppresses basal glycerol release in both sexes. Stage of the estrous cycle appears to influence the androgenic control of WAT metabolism. These findings suggest that local androgen control of WAT metabolism in males and females is mediated by local E2 levels, ERa:ERb, and steroidogenesis.
Sex Differences in Brain Development Affecting Cognition and Psychopathology
Results from the Philadelphia Neurodevelopment Cohort Sex differences in brain structure and function in relation to cognitive performance and psychopathology have been documented extensively in adults, but data are sparse on how these differences are modulated during development.
Sex Differences in Mismatch Negativity (MMN)-Indexed Auditory Change Detection in a Healthy Sample
Erica D. Rudolph1, Hayley Riel2, Catrina MacPhee3, Philip G. Tibbo2, and Derek J. Fisher4
1Saint Mary’s University, Halifax, NS, USA
2Dalhousie University, Halifax, NS, USA
3Acadia University, Wolfville, NS, USA
4Mount Saint Vincent University, Halifax, NS, USA
The mismatch negativity (MMN) is an EEG-derived marker of auditory change detection, an early and automatic cognitive process. Despite being commonly used to investigate changes in neuroelectric function in psychiatric and neurological populations, there are very few investigations of sex differences in the MMN and no studies examining differences in MMN elicited by pure tone stimuli. The aim of this study was to catalogue sex differences across a range of deviant types commonly employed in MMN research. We compared MMN amplitudes and latencies elicited by 5 different deviant types in 30 young healthy controls (15 males; 15 females). Participants were presented the “optimal” MMN paradigm comprised of standard tones (P = .5), as well as duration, gap, intensity, location, and pitch deviants (P = .1 each). EEG activity was recorded at 64 active electrode sites using Brain Vision PyCorder software. Significant differences (female > male; P < .05) were observed for MMN amplitudes to intensity deviants. This suggests that inherent sex differences exist for basic auditory change detection mechanisms. This provides evidence that studies of the MMN, including in clinical populations, should account for the biological sex of participants. Future work should examine whether these differences can be observed in middle- and older age populations.
Sex Differences in the Neuroinflammatory Effects of Pubertal Immune Stress on the Developing Brain
Daria Kolmogorova, BSc1, Briallen Carys Thomas2, James Gardner Gregory, PhD1, and Nafissa Ismail, PhD1
1NeuroImmunology, Stress, and Endocrinology (NISE) Laboratory, University of Ottawa, Ottawa, Ontario, Canada
2School of Biosciences, Cardiff University, Cardiff, Wales, United Kingdom
The extensive neuroplasticity of the developing pubertal brain creates a vulnerability to stress-induced changes in brain and behaviour. Furthermore, natural sex differences in physiological stress responses during puberty contribute to sex-based distinctions in stress reactivity and, therefore, stress sensitivity. In mice, for example, pubertal females tend to have significantly quicker recoveries to systemic pathogens than age-matched males. These sex differences during puberty may also impact the priming of microglia, the brain’s resident immune cells, and its neurotoxic effects. We tested whether sex influences microglial activation during puberty and its effects on neuronal death. Male and female CD-1 mice were treated with either the bacterial endotoxin lipopolysaccharide (LPS; 1.5 mg/kg body weight, ip) or 0.9% sterile saline (LPS-matched volume, ip) at 6 weeks old (ie, stress-sensitive pubertal period). Mice were then euthanized and intracardially perfused at either 24 hours, 1 week, or 4 weeks after treatment to examine changes during sickness, recovery, and early adulthood, respectively (n = 8/group). Cells labeled for iba-1 (microglia), NeuN (neurons), and caspase-3 (apoptosis) by immunocytofluorescence were counted in the hippocampus by 2 raters blinded to experimental group. A 2 × 2 × 3 ANOVA and Bonferroni-corrected post hoc tests examined sex and treatment effects on iba-1+, NeuN+, and caspase-3+ expression over time. As expected, pubertal LPS exposure increased iba-1+ cell expression during sickness, although LPS-treated females showed quicker iba-1+ cell proliferation and greater microglial activation compared to males (all P < .05). Changes in iba-1+ cells correlated with caspase-3+ cell expression on neurons (ie, NeuN+ cells). Our findings highlight natural sex differences in the vulnerability of the pubertal brain to neurotoxic microglial priming from immune challenges.
Sex-Specific Effects of Early Life Stress on Mast Cell Colonization and Activation in the Developing Rat Brain
Aarohi Joshi1, Courtney Dye1, Chloe E. Page1, Mark Damante1, Achikam Haim1, Benedetta Leuner1, and Kathryn M. Lenz1
1The Ohio State University, Columbus, OH, USA
Early life stress shapes brain and behavioral development and increases the risk for psychiatric disorders, yet the mechanisms through which stress impacts brain development are only partially elucidated. We study the role that brain-resident innate immune cells called mast cells may play in mediating the effects of perinatal perturbations on brain development. Mast cells are granulated immune cells that, when activated, release cytokines, proteases, prostaglandins, serotonin, and histamine into the microenvironment, thus can powerfully shape neural function. Previous reports show that mast cells are activated by adult stress exposure and we have shown that they are sexually dimorphic in the developing preoptic area, yet their responsiveness to early life stress is unknown. Here, we tested the effects of 3 different early life stress exposures: prenatal chronic variable stress, postnatal acute maternal separation stress, and repeated brief maternal separation stress, on mast cell number and activation in the hypothalamus and hippocampus of male and female rats, using toluidine blue staining and stereological cell counts. Prenatal stress exposure on gestational days 7 to 20 increased mast cell number and activation in the hypothalamus of females only. A single 3 hours maternal separation on postnatal day (PN) 2 decreased mast cell numbers in the hypothalamus and hippocampus of females, but not males. One week of 15 minutes maternal separation stress (PN4-11) increased mast cell numbers in the female, but not male, hippocampus. Control males had more mast cells than females in the hippocampus on the day of birth and more activated mast cells in both the hippocampus and hypothalamus on PN11. Overall, these studies show that mast cells are sexually dimorphic in the rodent brain around birth, and that, in females, mast cells are more responsive to early life stress. Mast cells may be an unappreciated mediator of sex-specific brain development in response to early life stress.