XCT790对缺氧、无血清及高糖诱导骨髓间充质干细胞凋亡的影响

Effect of XCT790 on MSCs apoptosis induced by serum deprivation，hypoxia and high glucose concentration

摘要:

目的：观察雌激素相关受体α（estrogen-related receptor α，ERRα）的特异性反向激动剂XCT790对无血清、缺氧及高糖诱导的C57BL/6小鼠骨髓间充质干细胞（mesenchymal stem cells，MSCs）凋亡的影响，并探讨其作用机制。方法：MSCs分为正常培养对照组（正常条件下培养）和0、5、10、20 μmol/L XCT790干预组（在3％ O2、无血清、25 mmol/L葡萄糖浓度条件下培养），以流式细胞仪Annexin V/7-AAD双染法检测各组在缺氧、缺营养、高葡萄糖条件下的凋亡率；Western blot检测B淋巴细胞瘤-2 （B cell lymphoma-2，Bcl-2）和Bax蛋白表达水平，并计算其比值。结果：缺氧、无血清及高糖诱导24 h后，5 μmol/L XCT790干预组（20.02±0.92）%、10 μmol/L XCT790干预组（26.04±1.24）%、20 μmol/L XCT790干预组（50.73±3.55）% 的凋亡率明显高于0 μmol/L XCT790干预组（14.34±0.61）%，呈剂量依赖性（P<0.05）。Western blot显示，前凋亡蛋白Bax的表达5 μmol/L XCT790干预组（0.132 3±0.033 8）、10 μmol/L XCT790干预组（0.140 8±0.006 8）、20 μmol/L XCT790干预组（0.199 4±0.061 7）较0 μmol/L XCT790组（0.116 4±0.017 2）明显升高，而凋亡蛋白Bcl-2表达5 μmol/L XCT790干预组（0.069 7±0.013 2）、10 μmol/L XCT790干预组（0.051 2±0.005 6）、20 μmol/L XCT790干预组（0.041 3±0.005 5）较0 μmol/L XCT790组（0.092 3±0.021 3）明显降低（P<0.05）。Bcl-2/Bax比值5 μmol/L XCT790干预组（0.530 7±0.027 9）、10 μmol/L XCT790干预组（0.397 9±0.004 2）、20 μmol/L XCT790干预组（0.234 8±0.032 1）较0 μmol/L XCT790组（0.851 7±0.084 4）明显降低，呈剂量依赖性（P<0.05）。结论：缺氧、无血清及高糖诱导下，拮抗ERRα可以使MSCs的凋亡率和Bcl-2/Bax比例明显降低，提示ERRα在细胞耐受凋亡过程中可能发挥重要保护作用。

Abstract:

Objective：To investigate the effects of XCT790 on bone mesenchymal stem cells（MSCs） apoptosis induced by hypoxia，serum deprivation and high glucose concentration. Methods：MSCs were divided into 5 groups：control group（cultrued under normal conditions） and 0-20 μmol/L XCT790 treatment groups（cultured under 3％ O2，serum deprivation and 25 mmol/L glucose concentra－tion）. The apoptosis rates were measured by Annexin V-APC /7-AAD on flow cytometry. The protein levels of Bcl-2 and Bax corre－lated with apoptosis were detected by Western blot. And the ratios of Bcl-2/Bax were calculated. Results：After being exposed to 5-20 μmol/L XCT790 for 24 h，the apoptosis rates of 5 μmol/L XCT790 treatment group（20.02±0.92）%，10 μmol/L XCT790 treatment group（26.04±1.24）% and 20 μmol/L XCT790 treatment group（50.73±3.55）% were significantly higher than of 0 μmol/L XCT790 treatment group（14.34±0.61）%，increasing in a dose-dependent manner（P<0.05）. Western blot showed the expression of pro-apop－totic protein Bax in 5 μmol/L XCT790 treatment group（0.132 3±0.033 8），10 μmol/L XCT790 treatment group（0.140 8±0.006 8） and 20 μmol/L XCT790 treatment group（0.199 4±0.061 7） was significantly higher than that in 0 μmol/L treatment group（0.116 4±0.017 2），while the expression of anti-apoptotic protein Bcl-2 in 5 μmol/L XCT790 treatment group（0.069 7±0.013 2），10 μmol/L XCT790 treatment group（0.051 2±0.005 6），20 μmol/L treat－ment group（0.041 3±0.005 5） was significantly lower than that in 0 μmol/L treatment group（0.092 3±0.021 3）. The Bcl-2/Bax ratios of 5 μmol/L XCT790 treatment group（0.530 7±0.027 9），10 μmol/L XCT790 treatment group（0.397 9±0.034 2） and 20 μmol/L XCT790 treatment group（0.234 8±0.032 1） were significantly lower than that in 0 μmol/L XCT790 treatment group（0.851 7±0.084 4），decreasing in a dose dependent manner（P<0.05）. Conclusion：In the conditions of hypoxia，serum deprivation and high glucose concentration，antagonism of estrogen-related receptor α makes MSCs apoptosis rates increase significantly as Bcl-2/Bax ratios decrease，which indicates that ERRα plays an important role in preventing MSCs apoptosis.