Hypoxia-ischemia (HI) is one of the leading causes of brain damage during the development of newborns. It can result in death or cause varying degrees of neurological disability. The only well-established treatment currently available for neonatal HI is therapeutic hypothermia (TH). However, TH is only partially protective, reducing severe disability by approximately 11%. Therefore, new therapeutic approaches are urgently needed. It is known that immature brains utilize higher levels of ketone bodies, such as β-hydroxybutyrate (BHB), that may contribute to resistance to hypoxic-ischemic events. In this study, 11-day-old animals were subjected to the neonatal HI (Rice-Vannucci model) and treated with TH alone or in combination with BHB administration. To assess brain metabolism, glucose uptake was evaluated using MicroPET at 72 hours post-injury and when the animals reached 65 days of age. Behavioral tests, brain volume analysis, hippocampal cell counting and the assessment of hippocampal inflammatory cytokines expression were also performed. Animals treated with BHB exhibited increased glucose uptake at 72 hours post-injury and a reduction in neuronal loss in the hippocampus. The combined use of BHB and TH resulted in enhanced hippocampal neuronal survival, suggesting that BHB may represent a promising future treatment for neonatal HI.
NelsonKBLynchJK.Stroke in newborn infants. Lancet Neurol2004;
3: 150–158.
2.
FerrieroDM.Neonatal brain injury. N Engl J Med2004;
351: 1985–1995.
3.
ShankaranSLaptookAREhrenkranzRA, et al.
Whole-body hypothermia for neonates with hypoxic–ischemic encephalopathy. N Engl J Med2005;
353: 1574–1584.
4.
ZhangSLiBZhangX, et al.
Birth asphyxia is associated with increased risk of cerebral palsy: a meta-analysis. Front Neurol2020;
11: 704–708.
5.
AbateBBBimerewMGebremichaelB, et al.
Effects of therapeutic hypothermia on death among asphyxiated neonates with hypoxicischemic encephalopathy: a systematic review and meta-analysis of randomized control trials. PLoS One2021;
16: e0247229–20.
6.
MathewJLKaurNDsouzaJM.Therapeutic hypothermia in neonatal hypoxic encephalopathy: a systematic review and meta-analysis. J Glob Health2022;
12: 04030. doi:DOI:10.7189/JOGH.12.04030.
7.
FabresRBNunesRRde Medeiros de MattosM, et al.
Therapeutic hypothermia for the treatment of neonatal hypoxia-ischemia: sex-dependent modulation of reactive astrogliosis. Metab Brain Dis2022;
37: 2315–2329.
8.
DavidsonJORoutALWassinkG, et al.
Non-additive effects of delayed connexin hemichannel blockade and hypothermia after cerebral ischemia in near-term fetal sheep. J Cereb Blood Flow Metab2015;
35: 2052–2061.
9.
GeorgeSABarrettRDBennetL, et al.
Nonadditive neuroprotection with early glutamate receptor blockade and delayed hypothermia after asphyxia in preterm fetal sheep. Stroke2012;
43: 3114–3117.
10.
DavidsonJOWassinkGvan den HeuijLG, et al.
Therapeutic hypothermia for neonatal hypoxic–ischemic encephalopathy – where to from here?Front Neurol2015;
6: 198.
11.
FabresRBMontesNLCamboimY. d M, et al.
Long-lasting actions of progesterone protect the neonatal brain following hypoxia-ischemia. Cell Mol Neurobiol2020;
40: 1417–1428.
12.
OdorcykFKDuran-CarabaliLERochaDS, et al.
Differential glucose and beta-hydroxybutyrate metabolism confers an intrinsic neuroprotection to the immature brain in a rat model of neonatal hypoxia ischemia. Exp Neurol2020;
330: 113317.
13.
JacobsSEBergMHuntR, et al.
Cooling for newborns with hypoxic ischaemic encephalopathy. Cochrane Database Syst Rev2013;
2013: CD003311.
14.
GlobusM‐TAlonsoODietrichWD, et al.
Glutamate release and free radical production following brain injury: effects of posttraumatic hypothermia. J Neurochem1995;
65: 1704–1711.
15.
BrekkeEMorkenTSSonnewaldU.Glucose metabolism and astrocyte–neuron interactions in the neonatal brain. Neurochem Int2015;
82: 33–41.
16.
RafikiABoullandJLHalestrapAP, et al.
Highly differential expression of the monocarboxylate transporters MCT2 and MCT4 in the developing rat brain. Neuroscience2003;
122: 677–688.
17.
NealEGChaffeHSchwartzRH, et al.
A randomized trial of classical and medium-chain triglyceride ketogenic diets in the treatment of childhood epilepsy. Epilepsia2009;
50: 1109–1117. doi:DOI:10.1111/j.1528-1167.2008.01870.x.
18.
CaiQ-YZhouZ-JLuoR, et al.
Safety and tolerability of the ketogenic diet used for the treatment of refractory childhood epilepsy: a systematic review of published prospective studies. World J Pediatr2017;
13: 528–536.
19.
LeeBSWooDCWooCWKimKS.Exogenous β-hydroxybutyrate treatment and neuroprotection in a suckling rat model of hypoxic-ischemic encephalopathy. Dev Neurosci2018;
40: 73–83.
20.
JugeNGrayJAOmoteH, et al.
Metabolic control of vesicular glutamate transport and release. Neuron2010;
68: 99–112.
21.
SempleBDBlomgrenKGimlinK, et al.
Brain development in rodents and humans: identifying benchmarks of maturation and vulnerability to injury across species. Prog Neurobiol2013;
106–107: 1–16.
22.
SizonenkoSVKissJZInderT, et al.
Distinctive neuropathologic alterations in the deep layers of the parietal cortex after moderate Ischemic-Hypoxic injury in the P3 immature rat brain. Pediatr Res2005;
57: 865–872.
23.
OdorcykFKRibeiroRTRoginskiAC, et al.
Differential age-dependent mitochondrial dysfunction, oxidative stress, and apoptosis induced by neonatal hypoxia-ischemia in the immature rat brain. Mol Neurobiol2021;
58: 2297–2308.
24.
National Research Council. Guide for the care and use of laboratory animals. 8th ed.
Washington, DC:
National Academies Press, 2011.
25.
Percie Du SertNHurstVAhluwaliaA, et al.
The ARRIVE guidelines 2.0: updated guidelines for reporting animal research. PLOS Biol2020;
18: e3000410.
26.
RiceJEVannucciRCBrierleyJB.The influence of immaturity on hypoxic‐ischemic brain damage in the rat. Ann Neurol1981;
9: 131–141.
27.
WoodTOsredkarDPuchadesM, et al.
Treatment temperature and insult severity influence the neuroprotective effects of therapeutic hypothermia. Sci Rep2016;
6: 23430.
28.
ZaniratiGAzevedoPNVenturinGT, et al.
Depression comorbidity in epileptic rats is related to brain glucose hypometabolism and hypersynchronicity in the metabolic network architecture. Epilepsia2018;
59: 923–934.
29.
CalabreseEBadeaAWatsonC, et al.
A quantitative magnetic resonance histology atlas of postnatal rat brain development with regional estimates of growth and variability. Neuroimage2013;
71: 196–206.
30.
NonoseYGewehrPEAlmeidaRF, et al.
Cortical bilateral adaptations in rats submitted to focal cerebral ischemia: emphasis on glial metabolism. Mol Neurobiol2018;
55: 2025–2041.
31.
MartiniAPRSchlemmerLMLucio PadilhaJA, et al.
Acrobatic training prevents learning impairments and astrocyte remodeling in the hippocampus of rats undergoing chronic cerebral hypoperfusion: sex-specific benefits. Front Rehabil Sci2024;
5: 1375561–14.
32.
SanchesEFArteniNSNicolaF, et al.
Early hypoxia-ischemia causes hemisphere and sex-dependent cognitive impairment and histological damage. Neuroscience2013;
237: 208–215.
33.
PaxinosGWatsonC.The rat brain in stereotaxic coordinates.
SanDiego, CA:
Elsevier S., 2007.
34.
ArteniNSPereiraLORodriguesAL, et al.
Lateralized and sex-dependent behavioral and morphological effects of unilateral neonatal cerebral hypoxia-ischemia in the rat. Behav Brain Res2010;
210: 92–98.
35.
FabresRBda RosaLAde SouzaSK, et al.
Effects of progesterone on the neonatal brain following hypoxia-ischemia. Metab Brain Dis2018;
33: 813–821.
36.
ChoKHTDavidsonJODeanJM, et al.
Cooling and immunomodulation for treating hypoxic-ischemic brain injury. Pediatr Int2020;
62: 770–778.
37.
ChoKHTWassinkGGalinskyR, et al.
Protective effects of delayed intraventricular TLR7 agonist administration on cerebral white and gray matter following asphyxia in the preterm fetal sheep. Sci Rep2019;
9: 9562–17.
38.
HagbergHMallardCFerrieroDM, et al.
The role of inflammation in perinatal brain injury. Nat Rev Neurol2015;
11: 192–208.
39.
OygürNSönmezÖSakaO, et al.
Predictive value of plasma and cerebrospinal fluid tumour necrosis factor-α and interleukin-1β concentrations on outcome of full term infants with hypoxic-ischaemic encephalopathy. Arch Dis Child Fetal Neonatal Ed1998;
79: 190–193.
40.
AlyHKhashabaMTEl-AyoutyM, et al.
IL-1β, IL-6 and TNF-α and outcomes of neonatal hypoxic ischemic encephalopathy. Brain Dev2006;
28: 178–182.
41.
AhearneCEChangRYWalshBH, et al.
Cord blood IL-16 is associated with 3-year neurodevelopmental outcomes in perinatal asphyxia and hypoxic-ischaemic encephalopathy. Dev Neurosci2017;
39: 59–65.
42.
De NicolaAFLabombardaFGonzalez DeniselleMC, et al.
Progesterone neuroprotection in traumatic CNS injury and motoneuron degeneration. Front Neuroendocrinol2009;
30: 173–187.
43.
van den HeuijLGFraserMMillerSL, et al.
Delayed intranasal infusion of human amnion epithelial cells improves white matter maturation after asphyxia in preterm fetal sheep. J Cereb Blood Flow Metab2019;
39: 223–239.
44.
DhikavVAnandK.Hippocampus in health and disease: an overview. Ann Indian Acad Neurol2012;
15: 239–246.
45.
XiongMYangYChenG, et al.
Post-ischemic hypothermia for 24 h in P7 rats rescues hippocampal neuron : Association with decreased astrocyte activation and inflammatory cytokine expression. Brain Res Bull2009;
79: 351–357.
46.
AllanSMRothwellNJ.Cytokines and acute neurodegeneration. Nat Rev Neurosci2001;
2: 734–744.
47.
AraqueACarmignotoGHaydonPG.Dynamic signaling between astrocytes and neurons. Annu Rev Physiol2001;
63: 795–813.
48.
LinCWangSXieJ, et al.
Ketogenic diet and β-hydroxybutyrate alleviate ischemic brain injury in mice via an IRAKM-dependent pathway. Eur J Pharmacol2023;
955: 175933.
49.
BackesHWalbererMLadwigA, et al.
Glucose consumption of inflammatory cells masks metabolic deficits in the brain. Neuroimage2016;
128: 54–62.
50.
PlourdeGRoumesHSuissaL, et al.
Neuroprotective effects of lactate and ketone bodies in acute brain injury. J Cereb Blood Flow Metab2024;
44: 1078–1088.
51.
SanchesEFArteniNNicolaF, et al.
Sexual dimorphism and brain lateralization impact behavioral and histological outcomes following hypoxia-ischemia in P3 and P7 rats. Neuroscience2015;
290: 581–593.
52.
OdorcykFKNicolaFDuran-CarabaliLE, et al.
Galantamine administration reduces reactive astrogliosis and upregulates the anti-oxidant enzyme catalase in rats submitted to neonatal hypoxia ischemia. Int J Dev Neurosci2017;
62: 15–24.
53.
JinL-WDi LucenteJRuiz MendiolaU, et al.
The ketone body β‐hydroxybutyrate shifts microglial metabolism and suppresses amyloid‐β oligomer‐induced inflammation in human microglia. Faseb J2023;
37: e23261. doi:DOI:10.1096/fj.202301254R.
54.
YenariMAHanHS.Neuroprotective mechanisms of hypothermia in brain ischaemia. Nat Rev Neurosci2012;
13: 267–278.
55.
KorcIBidegainMMartellM.Radicales libres bioquímica y sistemas antioxidantes implicancia en la patología neonatal. Rev Médica Del Uruguay1995;
11: 121–135.
56.
PrandiniMNNeves FilhoALapaAJ, et al.
Mild hypothermia reduces polymorphonuclear leukocytes infiltration in induced brain inflammation. Arq Neuropsiquiatr2005;
63: 779–784.
57.
GeorgeSBennetLWeaver-MikaereL, et al.
White matter protection with insulin-like growth factor 1 and hypothermia is not additive after severe reversible cerebral ischemia in term fetal sheep. Dev Neurosci2011;
33: 280–287.
58.
NettoCASanchesEOdorcykFK, et al.
Sex-dependent consequences of neonatal brain hypoxia-ischemia in the rat. J. Neurosci. Res2017;
95: 409–421.
59.
SanchesEFArteniNSSchererEB, et al.
Are the consequences of neonatal hypoxia-ischemia dependent on animals’ sex and brain lateralization?Brain Res2013;
1507: 105–114.
60.
JolyLMMucignatVMarianiJ, et al.
Caspase inhibition after neonatal ischemia in the rat brain. J Cereb Blood Flow Metab2004;
24: 124–131.
61.
AskalanRGabarinNArmstrongEA, et al.
Mechanisms of neurodegeneration after severe hypoxic-ischemic injury in the neonatal rat brain. Brain Res2015;
1629: 94–103.
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