XBP1 / CHOP / Puma 信号转导通路对高糖心肌细胞凋亡的作用研究

目的:探讨X 盒结合蛋白1(XBP1)通过调控XBP1/ CHOP/ Puma 信号转导通路对高糖诱导的H9C2 心肌细胞凋亡的影响。方法:实验分为4 组:低糖组(LG 组)、高糖刺激组(HG 组)、高糖+siRNA-NC 组(HG+NC 组)、高糖+siRNA-XBP1组(HG+siRNA 组);蛋白质免疫印迹(Western blot) 检测细胞转染后各组细胞中XBP1 蛋白、C/ EBP 同源蛋白(C/ EBP homologous protein,CHOP)、p53 上调凋亡调控因子(p53 upregulated modulator of apoptosis,Puma)、半胱氨酸天冬氨酸蛋白酶-3(Caspase-3),CCK-8 法检测细胞的增殖情况,流式细胞仪检测细胞的凋亡率。结果:siRNA-XBP1 可使心肌细胞XBP1 表达量降低(P<0.05)。与LG 组相比,HG 组、HG+NC 组、HG+siRNA 组细胞存活率均显著降低(P<0.05),凋亡率显著增高(P<0.05);与HG 组相比,HG+siRNA 组细胞存活率明显升高(P<0.05),凋亡率明显降低(P<0.05)。与LG 组相比,HG 组、HG+NC 组、HG+siRNA 组细胞中XBP1、CHOP、Puma、Caspase-3 的表达量均显著增加(均P<0.05);与HG 组相比,HG+siRNA 组细胞中XBP1、CHOP、Puma、Caspase-3 的表达量显著降低(P<0.05)。结论:XBP1 通过调节XBP1/ CHOP/ Puma 信号通路抑制高糖环境下心肌细胞凋亡、促进其增殖。

Effect of XBP1 / CHOP / Puma signaling pathway on apoptosis in cardiomyocyte of high glucose environment

Objective:To investigate the effect of X-box binding protein 1(XBP1) on the apoptosis of H9C2 cardiomyocytes under high glucose by XBP1/ CHOP/ Puma signaling pathway.Methods: The experiment were divided into four groups:low glucose group (LG group),high glucose group (HG group),high glucose+siRNA-NC group (HG+NC group),high glucose+siRNA-XBP1(HG +siRNA).The expression of XBP1,C/ EBP homologous protein (CHOP),p53 upregulated modulator of apoptosis(Puma),Caspase-3 in the cells after transfected were detected by Western blot;CCK-8 were used to detect the cell proliferation.Cell apoptosis was detected by flow cytometry.Results: siRNA-XBP1 reduced the expression of XBP1 in cardiomyocytes(P<0.05).Compared with LG group,the survival rate of HG group,HG +NC group and HG +siRNA group was significantly decreased (P <0.05),and the apoptosis rate was significantly increased (P<0.05).Compared with HG group,the survival rate of HG +siRNA group was significantly increased (P<0.05),and the apoptosis rate was significantly decreased (P<0.05).XBP1,CHOP,Puma in HG group,HG +NC group and HG +siRNA group was significantly higher than in LG group(P<0.05).Compared with HG group,the expression of XBP1,CHOP, Puma and Caspase-3 in HG +siRNA group was significantly lower (P<0.05).Conclusion: XBP1 inhibits cardiomyocyte apoptosis and promotes proliferation by regulating XBP1/ CHOP/ Puma signaling pathway.