P53在高糖诱导心肌细胞凋亡中的作用

Role of P53 in high glucose-induced apoptosis of cardiac muscle cells

目的探讨P53在高糖诱导心肌细胞凋亡中的作用。方法将培养的SD大鼠乳鼠心肌细胞随机分为4组:对照组、P53抑制剂组(葡萄糖浓度为5.5mmol/L,P53抑制剂浓度为50μmol/L)、高糖组(葡萄糖浓度为25mmol/L)和高糖+P53抑制剂组(P53抑制剂浓度为50μmol/L)。噻唑盐比色法(MTT法)检测心肌细胞活性,流式细胞术检测细胞凋亡,Western blot对各组细胞P53、BAX和Caspase-3进行半定量分析。结果与对照组相比,高糖组心肌细胞活力明显降低,凋亡率明显升高,Caspase-3、BAX和线粒体蛋白P53表达增多。与P53抑制剂组相比,高糖组心肌细胞活力明显降低,凋亡率明显升高,Caspase-3、BAX和线粒体蛋白P53表达增多;高糖+P53抑制剂组心肌细胞活力也有所降低,凋亡率升高,Caspase-3、BAX和线粒体蛋白P53表达增多。与高糖组相比,高糖+P53抑制剂组的心肌细胞活力增高,凋亡率明显降低,Caspase-3、BAX和线粒体蛋白P53表达减少。结论高糖可能通过介导P53转位到线粒体激活凋亡通路,引起心肌细胞凋亡。

Objective To study the role of P53 in high glucose-induced apoptosis of cardiac muscle cells.Methods Cardiac muscle cells from SD rats were cultured and randomly divided into control group,P53 inhibitor（pifithrin-α） group（with a glucose concentration of 5.5mmol/L and a concentration of 50μmol/L）,high glucose（25mmol/L） group,and high＋ pifithrinα（50μmol/L） group.Viability and apoptosis of cardiac muscle cells were detected by MTT assay and flow cytometry,respectively.Expression levels of P53,Bax and caspase-3 in cardiac muscle cells were measured by Western blot.Results The viability of cardiac muscle cells was significantly lower,the apoptosis rate of cardiac muscle cells was significantly higher,and the expression levels of P53,Bax and caspase-3 in cardiac muscle cells were significantly higher in high glucose group and high＋ pifithrin-α group than in control group and P53 inhibitor group（P0.05）.The viability of cardiac muscle cells was significantly higher,the apoptosis rate of cardiac muscle cells was significantly lower,and the expression levels of P53,Bax and caspase-3 in cardiac muscle cells were significantly lower in high glucose ＋ pifithrin-α group than in high glucose group（P0.05）.Conclusion High glucose can induce apoptosis of cardiac muscle cells by mediating transposition of P53 to mitochondria-activated apoptosis pathway.