摘要目的 探讨微RNA(miR)?9a?5p在H2O2致神经细胞损伤中的作用及其可能机制.方法 以PC12细胞为研究对象,CCK?8法和流式细胞仪检测H2O2处理对细胞增殖、凋亡的影响,同时检测H2O2处理对细胞乳酸脱氢酶(LDH)释放的影响,分析miR?9a?5p过表达和叉头框蛋白O1(FOXO1)抑制表达对H2O2致PC12细胞损伤的作用,双荧光素酶报告基因实验验证miR?9a?5p是否靶向作用于FOXO1,分析共表达miR?9a?5p和FOXO1对H2O2致PC12细胞损伤的影响.结果 H2O2处理PC12细胞,明显降低细胞存活率和细胞中miR?9a?5p的表达,诱导细胞凋亡率和LDH释放量增加,并促进细胞中FOXO1 mRNA和蛋白表达;miR?9a?5p过表达和FOXO1抑制表达均可逆转H2O2对PC12细胞的损伤;miR?9a?5p过表达抑制PC12细胞中FOXO1的表达,而miR?9a?5p抑制后促进细胞中FOXO1的表达,双荧光素酶报告基因实验证实FOXO1是miR?9a?5p的负调控靶基因;过表达FOXO1可逆转miR?9a?5p过表达对H2O2致PC12细胞损伤的保护作用.结论 miR?9a?5p可能通过靶向抑制FOXO1的表达,对H2O2致神经细胞损伤发挥保护作用.

abstractsObjective To investigate the effect of microRNA(miR)?9a?5p on H2O2?induced neuronal injury and its potential mechanism. Methods PC12 cells were included as the subjects in the study. CCK?8 method and flow cytometry were used to determine the effect of H2O2 treatment on cell proliferation and apoptosis. At the same time,the effect of H2O2 treatment on the release of cellular lactate dehydrogenase(LDH)was examined. The effect of miR?9a?5p overexpression and inhibition of forkhead box protein O1(FOXO1)expression on H2O2?induced PC12 cell injury was determined. The dual luciferase reporter assay identified whether miR?9a?5p targeted FOXO1. The effect of co?expression of miR?9a?5p and FOXO1 on H2O2?induced PC12 cell injury was determined. Results H2O2 treatment of PC12 cells significantly reduced cell viability and the expression level of miR?9a?5p,induced the increase of cell apoptosis and LDH release amount,and promoted mRNA and protein expression levels of FOXO1. Overexpression of miR?9a?5p and inhibition of FOXO1 all reversed the damage of H2O2 to PC12 cells. Overexpression of miR?9a?5p inhibited the expression of FOXO1 in PC12 cells,while the inhibition of miR?9a?5p promoted the expression of FOXO1. Dual luciferase reporter gene assay confirmed that FOXO1 was a negative regulatory target gene of miR?9a?5p. Overexpression of FOXO1 reversed the protective effect of miR?9a?5p overexpression on H2O2?induced PC12 cell injury. Conclusion miR?9a?5p may protect against H2O2?induced neuronal injury by targeted inhibition of FOXO1 expression.