高脂通过线粒体通路诱导H9c2心肌细胞损伤

High fatty acid induced H9c2 cardiomyocytes injury through mitochondrial pathways

目的探讨高脂通过线粒体凋亡通路对H9c2心肌细胞的损伤作用。方法棕榈酸(0～0.4 mmol·L^(-1))刺激H9c2心肌细胞24 h和0.2 mmol·L^(-1)棕榈酸刺激H9c2心肌细胞(0～48 h);MTT法评估细胞生长状态;活性氧试剂盒检测细胞内活性氧水平;凋亡试剂盒检测细胞凋亡情况;线粒体膜电位试剂盒检测线粒体膜电位变化;免疫印迹法检测细胞内线粒体凋亡相关蛋白Cyt-C、Cleaved casepase-3、Bax、Bcl-2表达水平。结果棕榈酸刺激H9c2心肌细胞24 h,棕榈酸0.2、0.4 mmol·L^(-1)组细胞增殖率均出现明显下降;细胞内活性氧水平逐渐升高,线粒体膜电位下降,细胞凋亡增加。棕榈酸(0.2 mmol·L^(-1))刺激H9c2心肌细胞24、36、48 h均引起细胞增殖率明显下降。棕榈酸(0.4 mmol·L^(-1))刺激H9c2心肌24 h,线粒体相关蛋白Cyt-C、Cleaved casepase-3、Bax表达均明显增高(P <0. 05),而Bcl-2明显降低(P <0. 05)。结论线粒体凋亡信号通路可能对高脂所致H9c2心肌细胞损伤起重要作用。

Aim To explore the role of mitochondrial apoptosis pathway in high fatty acid induced injury in H9c2 cardiomyocytes.Methods Cardiomyocytes were exposed to different concentrations of palmitic acid (PA) at 0~0.4 mmol·L^-1 for 24 h and different time points (0~48 h) of PA 0.2 mmol·L^-1 .Cell viability was measured by MTT;the intracellular reactive oxygen species(ROS) was detected by ROS kit;the cells were detected by apoptosis kit;the cell mitochondrial membrane potential changes were detected by mitochondrial membrane potential kit,and the protein expressions of mitochondrial apoptosis pathway such as Cyt-C,Cleaved caspase-3,Bax,and Bcl-2 were detected by Western blot.Results When the cells were stimulated with PA for 24 h,the cell proliferation rates of 0.2 and 0.4 mmol·L^-1 PA groups significantly decreased.The level of ROS increased gradually,the cell mitochondrial membrane potential decreased and the cell apoptosis increased.When the cells were stimulated with PA (0.2 mmol·L^-1 ) for 24 h,36 h and 48 h,and all of the cell proliferation rates showed significant decline.Cardiomyocytes exposed to PA (0.4 mmol·L^-1 ) for 24 h showed an increase in the expression of mitochondrial related proteins (Cyt-C,Cleaved caspase-3 and Bax)( P <0.05),while Bcl-2 expression was significantly reduced ( P <0.05).Conclusion Mitochondrial apoptosis signaling pathway might play an important role in high fatty acid induced H9c2 myocardial injury.