胰岛素样生长因子1受体在甲状腺相关性眼病眼眶脂肪细胞增殖和分化中的作用

目的 观察胰岛素样生长因子1（IGF-1）受体（IGF-1R）在甲状腺相关性眼病（TAO）眼眶脂肪组织中的表达及分布情况，探讨IGF-1对眼眶前脂肪细胞增殖和分化的影响。方法 收集2014年9月至2015年1月期间入住第二军医大学长征医院的TAO组患者（n=6）和对照组患者（n=5）的眼眶脂肪组织，用蛋白质印迹法、实时定量PCR及免疫组化法检测两组患者眼眶脂肪组织中IGF-1R的表达及分布情况。分别提取两组患者的眼眶前脂肪细胞，用CCK-8法检测不同浓度（0、1、5、10、20 nmol/L）IGF-1对细胞增殖能力的影响。体外分化细胞后用油红O染色法及蛋白质印迹法观察两组细胞的分化情况和IGF-1R的表达变化；实时定量PCR检测不同浓度（0、1、5、10、20 nmol/L）IGF-1对TAO组细胞分化水平的影响。结果 TAO组患者眼眶脂肪组织中IGF-1R蛋白及mRNA的表达均高于对照组（P<0.01）。不同浓度IGF-1均可以促进眼眶前脂肪细胞的增殖，且在1~20 nmol/L IGF-1作用下在TAO组细胞的增殖能力均高于对照组（P<0.05，P<0.01）。TAO组前脂肪细胞分化前、后细胞中IGF-1R的表达水平均明显高于对照组。相较于未加IGF-1组，1~20 nmol/L IGF-1均促进TAO组前脂肪细胞中PPARγ mRNA的表达（P<0.01）；油红O染色检测结果显示随着IGF-1浓度的升高，脂滴合成逐渐增加（P<0.05，P<0.01）。结论 IGF-1R在TAO患者脂肪组织及前脂肪细胞中的表达较高，IGF-1可以促进TAO眼眶前脂肪细胞的增殖和分化。
Objective To observe the expression and distribution of insulin-like growth factor-1 receptor (IGF-1R) in orbital adipose tissues of patients with thyroid-associated ophthalmopathy (TAO), and to explore the effect of insulin-like growth factor-1 (IGF-1) on the proliferation and differentiation of orbital preadipocytes. Methods We harvested the orbital adipose tissues from 6 patients with TAO (TAO group) and 5 controls (control group); the patients were treated in Changzheng Hospital, Second Military Medical University from Sep. 2014 to Jan. 2015. The expression and distribution of IGF-1R in the orbital adipose tissues were examined by Western blotting analysis, real-time PCR and immunohistochemistry. The orbital preadipocytes were extracted in two groups, and the effects of different concentrations of IGF-1 (0 nmol/L, 1 nmol/L, 5 nmol/L, 10 nmol/L, and 20 nmol/L) on cell proliferation were examined by CCK8. The differentiation of cells and the expression of IGF-1R were observed by oil red O staining and Western blotting; the effect of different concentrations of IGF-1 (0 nmol/L, 1 nmol/L, 5 nmol/L, 10 nmol/L, and 20 nmol/L) on preadipocyte differentiation was detected by real-time PCR. Results The expressions of IGF-1R protein and mRNA in orbital adipose tissues in TAO group were significantly higher than those in the control group (P<0.01). The proliferation of orbital preadipocytes was promoted in both groups, and the cell proliferation in TAO group was significantly higher than that in control group when treated with 1-20 nmol/L IGF-1 (P<0.05, P<0.01). The expression of IGF-1R in the TAO group was significantly higher than that in the control group before and after differentiation. Compared with IGF-1 absent group, 1-20 nmol/L IGF-1 significantly promoted the expression of PPARγ mRNA in orbital preadipocytes in TAO group