Sage Journals: Discover world-class research

Abstract

Purpose:

To explore the relationship between insulin-like growth factor (IGF)-1R expression and the pathological progression of Kashin-Beck disease (KBD).

Design:

KBD cartilage samples were collected from 5 patients. Additionally, T-2 toxin was administered to rats fed a selenium (Se)-deficient diet, and their knee joints were collected. Human C28/I2 chondrocytes and mouse hypertrophic ATDC5 chondrocytes were cultured in vitro and treated with T-2 toxin and Se supplementation. Subsequently, the cultured human and mouse chondrocytes were treated with the IGF-1R inhibitor, picropodophyllin. Chondrocyte death and caspase-3 activity were analyzed using flow cytometry and a specific kit, respectively. Protein and mRNA expression levels of IGF-1R and matrix molecules were measured using immunohistochemistry, western blotting, and quantitative real-time reverse transcription-polymerase chain reaction analyses.

Results:

The cartilages from patients with KBD and T-2 toxin-treated rats on a Se-deficient diet showed significantly decreased expression of IGF-1R compared to cartilages from controls. T-2 toxin decreased IGF-1R mRNA and protein levels in both C28/I2 and hypertrophic ATDC5 chondrocytes in a dose-dependent manner; however, Se supplementation reduced the decrease of IGF-1R induced by T-2 toxin. Furthermore, inhibition of IGF-1R resulted in chondrocyte death of C28/I2 and hypertrophic ATDC5 chondrocytes, as well as decreased type II collagen expression and increased MMP-13 expression at the mRNA and protein levels.

Conclusion:

Downregulation of IGF-1R was associated with KBD cartilage destruction. Therefore, inhibition of IGF-1R may mediate chondrocyte death and extracellular matrix degeneration related to the pathological progression of KBD.

Keywords

Kashin-Beck disease insulin-like growth factor-1 chondrocyte death extracellular matrix degeneration

Introduction

Kashin-Beck disease (KBD) is a chronic, endemic, deformable osteoarthropathy (OA) with a high rate of disability, which seriously endangers human health. T-2 mycotoxin contamination and selenium (Se) deficiency have been recognized as the main causes of KBD, which lead to cartilage damage.^1,2 Continuous development of KBD cartilage destruction and lack of self-repair ability have been shown to progressively cause impaired mobility, disability, and chronic pain.¹ While KBD cartilage destruction was mainly related to cartilage matrix metabolism, degeneration, and chondrocyte death.^1,3 Besides, chondrocyte necrosis in the deep zone and apoptosis in the middle zone of cartilage have been identified as the main pathological features of KBD,^4,5 but the underlying pathogenic mechanism remains unclear.

Our research group has previously described the histopathology of chondronecrosis in the knee articular cartilage in a rat model of KBD (induced by T-2 toxin and Se-deficient conditions), which showed similar pathological changes as observed in children with KBD.^6,7 Multiple studies have demonstrated that T-2 toxin promotes cartilage intracellular impairment and induces chondrocytes apoptosis.⁸ Therefore, T-2 toxin has been shown to regulate levels of type II collagen (Col II) and its regulatory enzymes MMPs/tissue inhibitor of metalloproteinase-1 (TIMP-1) in this rat model of KBD.⁹

Insulin-like growth factor-1 (IGF-1)/IGF-1R signaling affects hormones and mechanical signals through an autocrine/paracrine pathway, which enhances interactions between cells, thus promoting chondrocytes growth, survival, and differentiation.^10,11 In IGF-1R knockout mice, the decreased bodyweight, growth retardation, and significantly increased chondrocytes apoptosis were observed.¹² These mice also displayed muscular hypoplasia and delayed ossification, indicating that IGF-1R plays an important role in growth and development. Moreover, phosphorylation of IGF-1R is known to activate downstream pathways that upregulate transcription of Col II and aggrecan, which promote extracellular matrix (ECM) synthesis.¹³ The cartilage matrix protein, decorin, can also impact IGF-1R-dependent downstream signaling activation, thus affecting chondrocyte survival.¹⁴

To further assess the role of IGF-1R in regulating chondrocyte growth, this study investigated the relationship between IGF-1R and cartilage destruction in the development of KBD pathogenesis. And targeted IGF-1R inhibition in chondrocytes was conducted to elucidate its role in regulating chondrocyte death.

Methods

Human Cartilage Tissues

The cartilage samples were acquired from 5 children patients with KBD who lived in diseased areas and died from accidents or other diseases. The adult cartilage samples were obtained from 5 KBD patients undergoing joint replacement surgery at the Xi’an Jiaotong University of Medicine from 2010 to 2014. All the patients were diagnosed according to the internationally recognized diagnostic criteria (GB16003-1995) for KBD in China. The normal cartilage samples were obtained from non-KBD area patients, who had died from traffic accidents or amputations resulted from trauma, with no history of any form of osteoarthritis or other inflammatory joint diseases. The samples were acquired with the informed consent of each patient or guardian and were approved by the Human and Ethical Committee for Medical Research at Xi’an Jiaotong University, School of Medicine (No. 3063058, Dr. Yong Liu, Director).

Experimental Animal Model

Nighty 1-month-old Sprague-Dawley rats (male, mass: 60-80 g) were purchased from the animal center of Xi’an Jiaotong University. The rats were randomly divided into a control group and a Se-deficient group that fed with normal diet or Se-deficient diet for 4 weeks, respectively. The normal diet was prepared based on the AIN-93G and AIN-93-VX contained 0.35 mg/kg sodium selenite (Na₂O₄Se), while the sodium selenite was omitted in the mineral mix in a Se-deficient diet. The groups were then subdivided into 4 subgroups as follows: normal group (n = 20), Se-deficient group (n = 20), T-2 toxin group (100 ng/g body weight [BW]/day; n = 25), and Se-deficient plus T-2 toxin group (100 ng/g BW/day; n = 25). The rats were continuously fed with each specific diet for another 4 weeks, and T-2 toxin was intragastrically administrated. The protocol was approved by the Animal Ethics Committee, Medical School of Xi’an Jiaotong University (No. 0074). The use of animals in this study was by following National Institute of Health publication 85-23, Guide for Care and Use of Laboratory Animals.

Cell Culture

The C28/I2 immortalized chondrocytes were a gift from Mary B. Goldring (Hospital for Special Surgery, New York, USA). The ATDC5 chondrogenic cells were obtained from the European Collection of Cell Cultures. C28/I2 cells and hypertrophic ATDC5 cells were cultured in the Dulbecco’s modified Eagle’s medium/F-12 medium (HyClone, Logan, UT) with 10% fetal bovine serum (FBS; Gibco, Carlsbad, CA) containing various concentration gradients of T-2 toxin (T002980, TRC, Canada) and/or plus Na₂O₄Se (0.1 μg/mL) for 72 hours and 48 hours, respectively. The ATDC5 chondrocytes were differentiated into hypertrophic chondrocytes by using a medium containing 1% ITS (insulin-transferrin-selenium mix; I3146, Sigma) for 21 days.

IGF-1R Inhibition

The IGF-1R signaling specific inhibitor, picropodophyllin (PPP; Selleck, Houston, TX), was used in C28/I2 and hypertrophic ATDC5 cells with various concentrations for a different time, and the cells were used for further experiments.

Immunohistochemical (IHC) Staining and Quantification

Sections of 5 µm thickness cut from paraffin-embedded tissue blocks were deparaffinized and rehydrated. Samples were performed with a primary antibody to IGF-1R (1: 50, Abcam, Cambridge, MA), and then incubated with horseradish peroxidase-conjugated secondary antibody. The 3,3′-diaminobenzidine was used to visualize the IHC reaction (DAB; Zhongshan Golden Bridge, Beijing, China). The histologic sections were photographed using an Olympus BX51 microscope equipped for digital image acquisition.

Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR)

Total RNA was extracted using TRIzol reagent (Invitrogen, Carlsbad, CA). The complementary DNA was prepared from 1 mg of RNA using the RevertAid First-Strand Synthesis kit (Fermentas, Waltham, MA). The qRT-PCR reaction was performed on an iQ5 cycler (Biorad, Munich, Germany) using SYBR Green PCR Master Mix (Takara, Japan) with specific primers. The relative gene expression was normalized to the housekeeping gene (GAPDH) and quantified using the ΔCt method. The primer pairs for qRT-PCR are shown in the Supplemental Table 1.

Western Blotting

The protein samples separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis were transferred to polyvinylidene difluoride membranes (Millipore, Beverly, MA), and then incubated with IGF-1R antibody (1:1000, Abcam), MMP-13 (1:1000, Abcam), and Col II (1:500, Abcam). After incubated with anti-rabbit IgG (1:2000; CWBio, China), the membranes were developed with an enhanced chemiluminescence reagent (Millipore), and visualized by Chemidoc transilluminator (BioRad). Protein levels were standardized by comparison with GAPDH (1:1000; Proteintech).

Flow Cytometry Analysis

The chondrocyte apoptosis rate was analyzed using the Annexin V–FITC and PI apoptosis detection kit (BD Biosciences, San Diego, CA) and cells were double-stained with PI Annexin V and 7-amino-actinomycin. Samples were analyzed using a FACSCalibur flow cytometer (BD Biosciences).

Caspase-3 Activity Analysis

Caspase-3 activity was measured with a caspase-3 assay kit (Abcam, ab39401) according to the manufacturer’s protocol. And the caspase-3 activity was measured by fluorescence using a microplate reader at 405 nm.

Statistical Analysis

SPSS statistical software (Version 24.0; SPSS Inc., Chicago, IL) was used for data analysis, and the data were expressed as mean ± standard deviation (SD). T-test was used in the comparison between the 2 groups, and one-way analysis of variance (ANOVA) was used in the multigroups comparison. The LSD-q test was used for the further pairwise comparison. A P value of <0.05 was considered statistically significant.

Results

Decreased IGF-1R Immunostaining in Cartilages from Patients with KBD

The representative images of IHC showed that IGF-1R decreased in KBD children cartilage compared to that in healthy children cartilage ( Fig. 1A ), and the immunostaining quantitation results showed the lower ratio of IGF-1R-positive cells in the middle zone from KBD children cartilage than healthy cartilage, but there was no significant difference in the superficial zone and deep zone ( Fig. 1B ). Besides, IGF-1R expression was decreased in the KBD adult cartilage than in healthy adult cartilage ( Fig. 1C ). Meanwhile, the quantitation results showed a significant difference in superficial, middle, and deep zones of the articular cartilage from KBD adult cartilage compared to healthy adult cartilage ( Fig. 1D ).

Figure 1.

The immunostaining of IGF-1R in articular cartilage from healthy and KBD patients. (A) The representative images of IGF-1R immunostaining in healthy and KBD children cartilages, and (B) ratio of positive IGF-1R were measured. (C) The representative images of IGF-1R immunostaining in healthy and KBD adult cartilages, and (D) ratio of positive IGF-1R were measured (n = 5, **P < 0.01, ***P < 0.01; scale bars: 50 μm).

Decreased IGF-1R Immunostaining in Cartilages of Rat Model of KBD

IGF-1R expression was examined using IHC staining in articular cartilage and epiphyseal plate of rats treated with T-2 toxin and fed a Se-deficient diet. The IGF-1R expression was decreased in articular cartilages from the Se-deficient, T-2 toxin, and T-2 toxin plus Se-deficient groups compared to the control group ( Fig. 2A ). Compared with the control group, the ratio of IGF-1R-positive cells was significantly reduced in articular cartilage from the experimental groups ( Fig. 2C ). All epiphyseal plates of studied mice were divided into resting, proliferative, and hypertrophic zones. The representative images showed that IGF-1R expression was decreased in the Se-deficient, T-2 toxin, and T-2 toxin plus Se-deficient groups, but no IGF-1R staining was detected in the resting and proliferative zones of 3 experimental groups ( Fig. 2B ). The ratio of IGF-1R-positive cells significantly decreased in the experimental groups than that in the control group ( Fig. 2D ).

Figure 2.

The immunostaining of IGF-1R in the cartilage of animal model. (A) The immunostaining of IGF-1R in articular cartilage of rats. (B) The immunostaining of IGF-1R epiphyseal plate of rats. positively stained IGF-1R in articular cartilage and epiphyseal plate of rats. RZ, resting zone; PZ, proliferative zone; HZ, hypertrophic zone. (C) The ratios of IGF-1R-positive chondrocytes in articular cartilage of rats. (D) The ratios of IGF-1R-positive chondrocytes in epiphyseal plate of rats (n = 6, ***P < 0.01; scale bars: 50 μm).

Effect of T-2 Toxin and Se Supplementation on IGF-1R Expression in Chondrocytes

Two types of chondrocytes were used to study the effect of T-2 toxin and Se on the expression of IGF-1R. In C28/I2 chondrocytes, the relative level of IGF-1R mRNA was decreased in a dose-dependent manner induced by T-2 toxin ( Fig. 3A ). Western blotting bands and cumulative optical density of IGF-1R demonstrated statistically lower protein levels in T-2 toxin-induced C28/I2 chondrocytes than that in the control group ( Fig. 3B and C ). Furthermore, the mRNA level of IGF-1R also showed a significant decrease in T-2 toxin-treated hypertrophic ATDC5 chondrocytes ( Fig. 3D ), as well as the protein level of IGF-1R was decreased, compared with the control group ( Fig. 3E and F ). Moreover, Se-supplementation in both C28/I2 and hypertrophic ATDC5 chondrocytes could partially block the T-2 toxin-induced decrease in IGF-1R expression.

Figure 3.

The effect of T-2 toxin and Se on the expression of IGF-1R in C28/I2 and hypertrophic ATDC5 chondrocytes. (A) The mRNA level of IGF-1R in C28/I2 chondrocytes. (B) Western blotting bands. (C) The cumulative optical density analysis of IGF-1R in C28/I2 chondrocytes. (D) The mRNA level of IGF-1R in hypertrophic ATDC5 chondrocytes. (E) Western blotting bands. (F) The cumulative optical density analysis of IGF-1R in hypertrophic ATDC5 chondrocytes (n = 6, *P < 0.05, **P < 0.01, ***P < 0.001; ^# indicates the data from T-2 toxin plus Se group compared to the T-2 toxin group at same concentration, ^#P < 0.05).

Effect of IGF-1R Inhibition on Chondrocyte Death

The effect of IGF-1R inhibition on chondrocyte death was detected by flow cytometry in 2 cell lines ( Fig. 4A and E ). The results showed that IGF-1R inhibition in C28/I2 chondrocytes dose-dependent increased chondrocyte apoptosis, but had no effect on chondrocyte necrosis at 24 hours ( Fig. 4B and C ). While both the chondrocyte apoptosis and necrosis were significantly increased in C28/I2 cells after 48 hours of IGF-1R inhibition ( Fig. 4B and C ). To further confirm the effect of IGF-1R on chondrocyte death, the caspase-3 activity was detected. The results showed that the caspase-3 activity increased at both 24 hours and 48 hours following PPP treatment in C28/I2 cells ( Fig. 4D ). In hypertrophic ATDC5 chondrocytes, the ratio of cell necrosis was increased, while no statistical difference in chondrocyte apoptosis was observed after 24 hours of IGF-1R inhibition ( Fig. 4F and G ). Moreover, after 48 hours IGF-1R inhibition, the ratio of chondrocytes apoptosis and necrosis both increased compared to that in controls ( Fig. 4F and G ). Besides, the caspase-3 activity was significantly increased in hypertrophic ATDC5 chondrocytes at 48 hours post-IGF-1R inhibition ( Fig. 4H ). The IGF-1R inhibitor solvent dimethyl sulfoxide had no effect on chondrocyte death at the maximum concentration.

Figure 4.

The effect of IGF-1R inhibition on chondrocyte death. (A) The Annexin V-FITC/PI staining. (B) Quantitative of apoptosis rate. (C) Quantitative of necrosis rate. (D) The caspase-3 activity. (E) The Annexin V-FITC/PI staining. (F) Quantitative of apoptosis rate. (G) Quantitative of necrosis rate. (H) The caspase-3 activity (n = 3, *P < 0.05, **P < 0.01, ***P < 0.001).

Effect of IGF-1R on Cartilage Matrix Degradation

The cartilage matrix proteins were detected to investigate the effect of IGF-1R on matrix degradation. The result showed IGF-1R inhibition dose-dependently decreases Col II expression at the mRNA and protein levels ( Fig. 5A and B ), while the mRNA and protein expression of MMP-13 was increased in C28/I2 chondrocytes ( Fig. 5C and D ). Similar expression patterns were also observed in hypertrophic ATDC5 chondrocytes that the mRNA and protein expression of Col II was significantly decreased ( Fig. 5E and F ), while the expression of MMP-13 was increased after IGF-1R inhibition ( Fig. 5G and H ).

Figure 5.

The effect of IGF-1R inhibition on the expression of Col II and MMP-13 in chondrocytes. (A) The mRNA level and (B) protein level of Col II in C28/I2 chondrocytes. (C) The mRNA level and (D) protein level of MMP-13 in C28/I2 chondrocytes. (E) The mRNA level and (F) protein level of Col II in hypertrophic ATDC5 chondrocytes. (G) The mRNA level and (H) protein level of MMP-13 in hypertrophic ATDC5 chondrocytes (n = 3, *P < 0.05, **P < 0.01, ***P < 0.001).

Discussion

The main mechanisms of KBD cartilage destruction are excessive chondrocytes death and cartilage matrix degradation. This study showed a significant decrease in IGF-1R expression in the articular cartilage of patients with KBD, suggesting a correlation between abnormal IGF-1R expression and KBD cartilage destruction.

To further investigate the role of IGF-1R in KBD cartilage destruction, the T-2 toxin/Se-deficient rat model of KBD was used in this study. In previous studies, both T-2 toxin and Se deficiency led to cartilage destruction in rats, as well as reduced proteoglycan and Col II expression and altered expression of MMPs.⁹ Besides, chondrocytes apoptosis was demonstrated by the presence of cell lacunae and increased expression of caspase-3, p53, and Bax in the rat cartilages.^6,7 These chondrogenesis lesions were comparable to cartilage damage observed in KBD. Besides, cartilage-specific IGF-1R knock-out mice die shortly after birth and with less mineralized skeletons, as a result of severe chondrocyte defects characterized by reduced proliferation, delayed differentiation and hypertrophy, and increased chondrocyte apoptosis.^11,12,15 Thus, decreased IGF-1R expression in articular cartilage and epiphyseal plate of rats exposed to T-2 toxin and Se-deficient conditions, suggesting that IGF-1R may involve in cartilage destruction caused by T-2 toxin in rats model. Articular cartilage has a highly organized structure composed of the superficial zone, middle zone, deep zone, and calcified zone. The chondrocyte phenotype and shape vary among the different zones. In this study, the subtle zonal differences of IGF-1R expression in rat articular cartilage may indicate that T-2 toxin has a different sensitivity to chondrocytes with different phenotypes, which need to be studied further.

Besides, the hypertrophic ATDC5 chondrocytes were used as targeted cells to investigate chondrocytes changes in the deep zone of articular cartilage where they act as the most commonly affected anatomical site of KBD patients.¹ T-2 toxin was shown to induce chondrocyte death by increasing the Bax/Bcl-2 ratio and enhancing matrix degradation through Col II and MMPs.⁸ The decreased IGF-1R expression induced by the T-2 toxin indicates the IGF-1R may involve in the T-2 toxin-induced chondrocyte death. Moreover, Se as an essential nutrient and trace element that is required for human health, its supplementation partially increases the expression of IGF-1R, which also protects the cell from death. Together, the results from the KBD rat model and chondrocytes indicate the involvement of IGF-1R in the T-2 toxin-induced cartilage and chondrocyte destruction.

IGF-1R/IGF-1 signaling activates critical cell survival factors to protect cells from apoptosis through several downstream pathways, including the phosphatidylinositol-3 kinase (PI3K)/protein kinase B (PKB) pathway, interleukin-Iβ-converting enzymes (ICE), and ICE-like proteases.^16,17 A specific IGF-1R inhibitor PPP, which efficiently blocks IGF-1R activity,¹⁸ was used to investigate the involvement of IGF-1R in regulating chondrocyte death and ECM degradation. Present data showed that the inhibition of IGF-1R induced both chondrocytes apoptosis and necrosis at 48 hours in these 2 cell lines. But the 24 hours IGF-1R inhibition caused apoptosis in C28/I2 and necrosis in hypertrophic ATDC5 cells, which is consistent with the KBD cartilage destruction that apoptosis occurs at the middle zone while necrosis mainly occurs at the deep zone of cartilage.^3,5 Besides, a previous study showed that T-2 toxin increases apoptosis, with no effect on necrosis, of C28/I2 chondrocytes.¹⁹ Several studies demonstrated the IGF-1R signaling regulating the proliferation and differentiation, which may speculate the role of IGF-1R in regulating the death of chondrocytes with different phenotypes in different ways.¹⁶ Besides, the increased caspase-3 activity in chondrocytes after IGF-1R inhibition further confirming the involvement of IGF-1R in regulating chondrocyte death. Hence, IGF-1R inhibition in chondrocytes suggests its involvement in regulating KBD chondrocyte death.

Since IGF-1/IGF-1R signaling pathway also responsible for regulating ECM protein synthesis in articular cartilage, notably collagens and proteoglycan.²⁰ And gene silencing of IGF-1R downregulated Col II expression and upregulated MMPs in several cell types through activation of downstream PI3K signal pathways.^13,20 Besides, the increased matrix metabolism during KBD cartilage destruction has been confirmed. Our present data showed that inhibition of IGF-1R in chondrocytes induced the downregulation of Col II and upregulation of MMP-13, indicating the involvement of IGF-1R in T-2 toxin-induced ECM degradation.

Taken together, this study showed decreased IGF-1R expression in the cartilage of KBD patients. Furthermore, T-2 toxin-induced the downregulation of IGF-1R in the cartilage of a KBD rat model and in chondrocytes in vitro. Inhibition of IGF-1R signaling was shown to result in chondrocyte death and ECM degeneration. Therefore, we speculate that downregulation of IGF-1R is involved in the development of KBD through regulation of chondrocyte death and ECM degradation. Further study is needed to clarify the specific mechanism of IGF-1R in the pathological progression of KBD cartilage destruction.

Supplemental Material

sj-pdf-1-car-10.1177_19476035211021890 – Supplemental material for Downregulation of Insulin-Like Growth Factor-1 Receptor Mediates Chondrocyte Death and Matrix Degradation in Kashin-Beck Disease

Supplemental material, sj-pdf-1-car-10.1177_19476035211021890 for Downregulation of Insulin-Like Growth Factor-1 Receptor Mediates Chondrocyte Death and Matrix Degradation in Kashin-Beck Disease by Meng Zhang, Wenjun Wang, Hui Wang, Yinan Liu, Zhengzheng Li, Chengfen Yi, Yawen Shi, Tianyou Ma and Jinghong Chen in CARTILAGE

Footnotes

Acknowledgments and Funding

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study supported by the National Natural Science Foundation of China (No. 81872565, No. 81573102).

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Ethics Approval

The study was approved by the Human and Ethical Committee for Medical Research at Xi’an Jiaotong University, School of Medicine (No. 3063058, Dr. Yong Liu, Director).

Informed Consent

The samples were acquired with the informed consent of each patient or guardian.

ORCID iD

Meng Zhang

Supplementary material for this article is available on the Cartilage website at .

References

Guo

Zhang

Ren

Lammi

MJ.

Recent advances in the research of an endemic osteochondropathy in China: Kashin-Beck disease. Osteoarthritis Cartilage. 2014;22(11):1774-83. doi:10.1016/j.joca.2014.07.023

Allander

Kashin-Beck disease. An analysis of research and public health activities based on a bibliography 1849-1992. Scand J Rheumatol Suppl. 1994;99:1-36. doi:10.3109/03009749409117126

Chen

Luo

Wang

Zhang

Duance

, et al. Altered proteolytic activity and expression of MMPs and aggrecanases and their inhibitors in Kashin-Beck disease. J Orthop Res. 2015;33(1_suppl):47-55. doi:10.1002/jor.22708

Wang

Guo

Zuo

Zhang

Ping

, et al. Chondrocyte apoptosis and expression of Bcl-2, Bax, Fas, and iNOS in articular cartilage in patients with Kashin-Beck disease. J Rheumatol. 2006;33(3):615-9.

Zhang

Wang

Zhang

, et al. Death of chondrocytes in Kashin-Beck disease: apoptosis, necrosis or necroptosis? Int J Exp Pathol. 2018;99(6):312-22. doi:10.1111/iep.12297

Guan

Wang

Yang

Xue

Wang

, et al. Histopathology of chondronecrosis development in knee articular cartilage in a rat model of Kashin-Beck disease using T-2 toxin and selenium deficiency conditions. Rheumatol Int. 2012;33(1_suppl):157-66. doi:10.1007/s00296-011-2335-7

Yang

Zhang

Wang

Xue

Zhou

, et al. Increased chondrocyte apoptosis in Kashin-Beck disease and rats induced by T-2 toxin and selenium deficiency. Biomed Environ Sci. 2017;30(5):351-62. doi:10.3967/bes2017.046

Chen

Chu

Cao

Yang

Guo

Wang

T-2 toxin induces apoptosis, and selenium partly blocks, T-2 toxin induced apoptosis in chondrocytes through modulation of the Bax/Bcl-2 ratio. Food Chem Toxicol. 2006;44(4):567-73. doi:10.1016/j.fct.2005.09.004

Zhou

Yang

Guan

Xue

Song

Chen

, et al. T-2 toxin alters the levels of collagen II and its regulatory enzymes MMPs/TIMP-1 in a low-selenium rat model of Kashin-Beck disease. Biol Trace Elem Res. 2016;169(2):237-46. doi:10.1007/s12011-015-0408-2

10.

Hakuno

Takahashi

SI.

IGF1 receptor signaling pathways. J Mol Endocrinol. 2018;61(1_suppl):T69-T86. doi:10.1530/jme-17-0311

11.

Wang

Cheng

Elalieh

Nakamura

Nguyen

Mackem

, et al. IGF-1R signaling in chondrocytes modulates growth plate development by interacting with the PTHrP/Ihh pathway. J Bone Miner Res. 2011;26(7):1437-46. doi:10.1002/jbmr.359

12.

Liu

Baker

Perkins

Robertson

Efstratiadis

Mice carrying null mutations of the genes encoding insulin-like growth factor I (Igf-1) and type 1 IGF receptor (Igf1r). Cell. 1993;75(1_suppl):59-72.

13.

Afratis

Bouris

Skandalis

Multhaupt

Couchman

Theocharis

, et al. IGF-IR cooperates with ERα to inhibit breast cancer cell aggressiveness by regulating the expression and localisation of ECM molecules. Sci Rep. 2017;7:40138. doi:10.1038/srep40138

14.

Iozzo

Buraschi

Genua

Solomides

Peiper

, et al. Decorin antagonizes IGF receptor I (IGF-IR) function by interfering with IGF-IR activity and attenuating downstream signaling. J Biol Chem. 2011;286(40):34712-21. doi:10.1074/jbc.M111.262766

15.

Wang

Bikle

Chang

Autocrine and paracrine actions of IGF-I signaling in skeletal development. Bone Res. 2013;1(3):249-59. doi:10.4248/BR201303003

16.

Vincent

Feldman

EL.

Control of cell survival by IGF signaling pathways. Growth Horm IGF Res. 2002;12(4):193-7. doi:10.1016/s1096-6374(02)00017-5

17.

Starkman

Cravero

Delcarlo

Loeser

RF.

IGF-I stimulation of proteoglycan synthesis by chondrocytes requires activation of the PI3-kinase pathway but not ERK MAPK. Biochem J. 2005;389(pt 3):723-9. doi:10.1042/bj20041636

18.

Hixon

Paccagnella

Millham

Perez-Olle

Gualberto

Development of inhibitors of the IGF-IR/PI3K/Akt/mTOR pathway. Rev Recent Clin Trials. 2010;5(3):189-208. doi:10.2174/157488710792007329

19.

Liu

Jiang

Wang

Liu

, et al. Integrin α2β1 is involved in T-2 toxin-induced decrease of type II collagen in C28/I2 chondrocytes. Toxicon. 2020;186:12-8. doi:10.1016/j.toxicon.2020.07.016

20.

McQuillan

Handley

Campbell

Bolis

Milway

Herington

AC.

Stimulation of proteoglycan biosynthesis by serum and insulin-like growth factor-I in cultured bovine articular cartilage. Biochem J. 1986;240(2):423-30. doi:10.1042/bj2400423

Supplementary Material

Please find the following supplemental material available below.

For Open Access articles published under a Creative Commons License, all supplemental material carries the same license as the article it is associated with.

For non-Open Access articles published, all supplemental material carries a non-exclusive license, and permission requests for re-use of supplemental material or any part of supplemental material shall be sent directly to the copyright owner as specified in the copyright notice associated with the article.

0.00 MB

0.06 MB