组织蛋白酶S抑制剂对兔血管平滑肌细胞凋亡的影响

目的 研究组织蛋白酶S抑制剂对培养的兔血管平滑肌细胞凋亡的影响及其机制.方法 获取兔主动脉组织,传代培养血管平滑肌细胞,将细胞分为对照组、单药组(血管紧张素Ⅱ)、联合组(组织蛋白酶S抑制剂+血管紧张素Ⅱ);采用流式细胞术和脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(TUNEL)检测血管平滑肌细胞凋亡,蛋白质印迹法检测B细胞淋巴瘤基因-2蛋白、B细胞淋巴瘤基因-2相关蛋白X及半胱氨酸天冬氨酸特异性蛋白酶-3的表达.结果 ①流式细胞术检查及TUNEL染色结果均显示,联合组血管平滑肌细胞晚期凋亡数量明显低于单药组;TUNEL染色10 h和12 h时点,单药组与联合组差异有统计学意义 10 h:(23607±176)比(36058±269)个,12 b:(29813±205)比(39146±263)个,均P＜0.05];②蛋白质印迹检测结果显示,与单药组相比,联合组B细胞淋巴瘤基因-2相关蛋白X/B细胞淋巴瘤基因-2蛋白明显下降,组间差异有统计学意义(P＜0.05);联合组半胱氨酸天冬氨酸特异性蛋白酶-3表达明显降低,组间差异有统计学意义(P＜0.05).结论 组织蛋白酶S抑制剂可能通过下调B细胞淋巴瘤基因-2相关蛋白X、半胱氨酸天冬氨酸特异性蛋白酶-3表达减轻血管平滑肌细胞凋亡.

The effect of cathepsin S inhibitor on the apoptosis of rabbit vascular smooth muscle cells

Objective To observe the effects and mechanisms of Cathepsin S（CTSS） inhibitor on the apop- tosis of vascular smooth muscle cells （VSMC）. Methods Vascular smooth muscle cells of rabbit were primary cul- tured from aortic tissue and subcultured. VSMCs were divided into control group, one drug group （ angiotensin I1 ） and combined drugs group （ CTTS inhibitor ＋ angiotensin Ⅱ） ; we used flow cytometry and TUNEL to detect the change of apoptosis of VSMC. Western-blotting was applied to detect the expression of apoptosis related protein Bcl- 2, Bax, Caspase-3. Results ①Both flow cytometry and TUNEL showed that at the time points （10h, 12h）, com- pared with one drug group,the apoptosis of VSMC in combined drugs group alleviated remarkably, the difference was statistically significant 10h ： （ 23607±176 ） vs （ 36058±269 ）, 12h ： （ 29813±205 ） vs （ 39146±263 ）, both P 〈 0.05 ] ②Western-blotting： compared with one drug group, combined drugs group could down-regulate the ratio of the expression of the apoptosis related protein Bax/Bcl-2 obviously （ P 〈 0.05 ） ; the expression of apoptosis related protein Caspase-3 reduced obviously（P 〈0.05）. Conclusion Cathepsin S inhibitor may alleviate the apoptosis of VSMC by down-regulating the expression of apoptosis related protein BAX and Caspase-3.