中文摘要：

目的探讨衰老心肌中增加的Omi／HtrA2在心肌细胞自噬中的作用。方法用D-半乳糖干预胎鼠心肌细胞系H9c2建立衰老细胞模型，B-半乳糖苷酶染色观察细胞的衰老情况，cck8试剂盒检测细胞存活率，并以分析细胞乳酸脱氢酶（Lactic Dehydrogenase，LDH）水平反映其活性；给予Omi／HtrA2特异性抑制剂ucf_101降低Omi／HtrA2活性，构建稳转Omi／HtrA2的H9c2细胞株过表达Omi／HtrA2；采用westernblot法测定心肌细胞中Omi／HtrA2、beclinl及LC3．II蛋白的表达。结果（1）与H9c2心肌细胞相比，D．半乳糖诱导的H9c2心肌细胞内B-半乳糖苷酶染色阳性率显著升高[（87．7±3．6％）VS（18．3±2_8％），P〈0．01]；cck8结果显示，两组之间无显著性差异（P〉0．05），但D-半乳糖诱导的H9c2心肌细胞中LDH活性明显升高（7．07±0．65w5．93±0．34，P〈0．01o（2）与H9c2细胞相比，D-半乳糖诱导的H9c24心肌细胞中Omi／HtrA2蛋白表达升高（P〈0．05），而beclinl表达下降（P〈0．01）；给予ucf-101后，衰老细胞中Omi／HtrA2蛋白表达明显下降（P〈0．05），而beclinl表达则进一步降低（P〈0．01）。（3）与H9c2细胞相比，过表达Omi／HtrA2的H9c2心肌细胞Omi／HtrA2蛋白表达增高，LC3-Ⅱ蛋白表达也增高（P〈0．05）；给予过表达Omi／HtrA2的H9c2心肌细胞ucf-101后，LC3-Ⅱ表达下降（P〈0．05o结论衰老心肌细胞中Omi／HtrA2的表达增加可促进心肌细胞自噬。

英文摘要：

Objective To investigate the effects of increased expression of Omi/HtrA2 on myocardial autophagy in aging myocardiocytes. Methods The rat embryonic myocardial cell line H9c2 was induced by D-galactose （8g/L） to establish aging model. Cell aging was detected by β-galactosidase staining. Cell viability was detected by CCK8 kits and lactic dehydrogenase （LDH） activity analysis. Ucf-101, a specific inhibitor of Omi/HtrA2, was used to inhibit the activity of Omi/HtrA2, and the H9c2 cells with stable transfection of Omi/HtrA2 was constructed to increase the expression of Omi/HtrA2. The expression of Omi/HtrA2, beclinl and LC3- I/ were detected by Western blotting. Results （1） D-galactose resulted in a significant increase in positive staining to ~-galactosidase in the induced cardiacmyocytes than the H9c2 cells [（87.7 ± 3.60）% vs （918.3 ± 2.80）%, P〈 0.01]. The cck8 results showed that there was no significant difference between the cells with and without D-galactose inducement （P 〉 0.05）. LDH activity was increased in the induced H9c2 cells than those without （7.07 ± 0.65 vs 5.93 ± 3.36, P 〈 0.01）. （2） The expression of Omi/HtrA2 was increased （P 〈 0.05）, but the expression of beclinl was decreased （P 〈 0.01） in cells induced by D-galactose, as compared with H9c2 cells. In cells treated with ucf-101, the expression of Omi/HtrA2 was significantly decreased （P 〈 0.05）, but the expression of