SIRT1通过促进eIF2α去乙酰化抑制PC12细胞氧化应激反应

SIRT1 inhibits oxidative stress in PC12 cells by promoting deacetylation of eIF2α

目的:研究沉默信息调节因2相关酶1(SIRT1)和真核起始因子2α(eIF2α)在PC12细胞氧化应激过程中的作用。方法:大鼠肾上腺嗜铬细胞瘤来源的PC12细胞分为4组:对照组(Control)、D-半乳糖处理组(D-gal)、白藜芦醇处理组(RSV)、RSV和EX527联合处理组(RSV+EX527),利用D-gal处理制备神经细胞氧化应激模型,MTT法检测细胞增殖活性,real time RT-PCR检测SIRT1和eIF2αm RNA水平变化,利用商品化试剂盒检测各组细胞中氧化应激,利用免疫共沉淀(Co-IP)技术检测eIF2α去乙酰化水平。结果:与正常对照组相比,D-gal处理组细胞的活性下降,SIRT1和SOD表达下降,GSH水平下降,MDA水平升高,eIF2α去乙酰化水平降低;RSV处理后,SOD活性增加,GSH水平升高,MDA水平下降,eIF2α去乙酰化水平增加;EX527+RSV联合处理后,RSV导致的上述变化减弱或消失。结论:在PC12细胞中SIRT1能够通过eIF2α去乙酰化抑制细胞氧化应激而发挥保护作用。

Objective: To investigate the role of silent mating type information regulation 2 homolog-1(SIRT1) and eukaryotic initiation factor 2(eIF2α) in cellular oxidative stress. Methods: Rat adrenal pheochromocytoma derived PC12 cells were divided into four groups: Control group,D-galactose group(D-gal),resveratrol group(RSV),RSV and EX527 group(RSV + EX527). Cell oxidative stress model was induced by teratment with D-gal. The cell proliferation activity was tested by MTT method. The expression of SIRT1 and eIF2α m RNA was tested using real time RT-PCR.Oxidative stress was measured by using commercial kits. The eIF2α deacetylation levels were measured using Co-immunoprecipitation(Co-IP). Results: Compared with control group,the D-gal treatment group showed decreased cell activity,decreased SIRT1 and SOD expression,decreased GSH level,increased MDA level,and decreased eIF2α deacetylation level. After RSV treatment,SOD activity increased,GSH level increased,MDA level decreased,and eIF2αdeacetylation level increased. After EX527 + RSV combined treatment,the above changes caused by RSV weakened or disappeared. Conclusion: SIRT1 inhibits oxidative stress in PC12 cells by promoting eIF2α deacetylation.