Xiao Wei-Min, Jiang Bi-Mei, Shi Yong-Zhong
Department of Pathophysiology, Xiangya School of Medicine, Central South University, Changsha 410078, China.
Zhong Nan Da Xue Xue Bao Yi Xue Ban. 2004 Feb;29(1):6-10.
To explore the mechanisms of C2C12 cell apoptosis induced by hydrogen peroxide (H2O2) which is inhibited by heat shock proteins.
The expression of heat shock proteins in mouse embryonic myogenic cell line, C2C12 cell,was induced by heat shock response. C2C12 cell apoptosis induced by 0.5 mmol/L hydrogen peroxide (H2O2) was determined by Hoechst 33258 staining. The activities of caspase -3,8,9 were assayed by caspase colorimetric assay kit and Western-blotting. The release of cytochrome C from mitochondria was observed by Western-blotting of cell mitochondria and cytosol fractions.
The expression of HSP70 and alphaB-crystallin in C2C12 cell significantly increased at 24 hour after the heat shock response. Heat shock response could inhibit the release of cytochrome c from mitochondria to cytoplasm,the activation of caspase -3,8,9 and the subsequent apoptosis induced by H2O2 in C2C12 cell.
HSPs can inhibit the C2C12 cell apoptosis through interference with the activation of both mitochondrial and death receptor pathways, which can provide new clues for the prevention of cardiovascular diseases.
探讨热休克蛋白抑制过氧化氢（H2O2）诱导的C2C12细胞凋亡的机制。
通过热休克反应诱导小鼠胚胎成肌细胞系C2C12细胞中热休克蛋白的表达。采用Hoechst 33258染色法检测0.5 mmol/L过氧化氢（H2O2）诱导的C2C12细胞凋亡情况。使用半胱天冬酶比色测定试剂盒和蛋白质免疫印迹法检测半胱天冬酶-3、8、9的活性。通过对细胞线粒体和胞质部分进行蛋白质免疫印迹法观察细胞色素C从线粒体的释放情况。
热休克反应后24小时，C2C12细胞中HSP70和αB-晶状体蛋白的表达显著增加。热休克反应可抑制细胞色素c从线粒体释放到细胞质，抑制半胱天冬酶-3、8、9的激活以及随后H2O2诱导的C2C12细胞凋亡。
热休克蛋白可通过干扰线粒体和死亡受体途径的激活来抑制C2C12细胞凋亡，这可为心血管疾病的预防提供新线索。
