Akt参与热休克蛋白27保护大鼠心肌细胞过氧化损伤  

Akt is involved in the cytoprotection of Heat shock protein27 from H_2O_2-induced damage in rat cardiac cells

作　　者：庞斯斯[1] 张小进[1] 姜苏蓉[1] 刘莉[1] 程蕴琳[1] 

机构地区：[1]南京医科大学第一附属医院老年医学科,江苏南京210029

出　　处：《南京医科大学学报（自然科学版）》2008年第5期613-617,共5页Journal of Nanjing Medical University(Natural Sciences)

基　　金：江苏省卫生厅"十一五兴卫工程/老年医学重点学科"专向基金;江苏省科技厅自然科学基金(BK2007247);教育部博士点专项基金(20050312008)

摘　　要：目的:探讨小分子热休克蛋白27保护大鼠心肌细胞过氧化损伤的机制。方法:①以稳定转染pCDNA3.1/Hsp27质粒并稳定高表达Hsp27的大鼠心肌细胞株H9c2(H9c2-Hsp27)为研究对象,对照组采用稳定转染pCDNA3.1质粒的H9c2(H9c2-Vector)细胞;②氧化应激诱导和检测:500 μmol/LH2O2处理细胞后进行如下分析:培养上清中的LDH活性、细胞形态学改变、细胞内Akt激活水平;③Akt在Hsp27保护H2O2诱导H9c2损伤中的作用:以Akt抑制剂Triciribine处理H9c2-Hsp27,观察其对Hsp27保护H2O2诱导H9c2形态学变化的影响。结果:①H2O2诱导H9c2细胞向培养上清释放的LDH显著增加(P<0.01),但与对照组相比,Hsp27高表达显著抑制了H2O2诱导的LDH释放(P<0.01);②H2O2处理后,H9c2细胞Akt磷酸化水平增加(P<0.01或P<0.05),但与H9c2-Vector比较,H9c2-Hsp27的Akt磷酸化水平进一步增强(P<0.05);③Akt磷酸化被抑制后,Hsp27对H2O2诱导H9c2细胞形态学改变的保护作用消失。结论:Akt激活是Hsp27保护大鼠心肌细胞过氧化损伤的重要机制。Objective：To investigate the mechanisms of the cytoprotection of Heat shock protein27 （Hsp27） from HzOz-induced damage in rat cardiac cells. Methods：（1）Rat cardiac cell line H9c2 with stable overexpression of Hsp27（H9c2-Hsp27） was used in the experiment,empty vector transfected H9c2（H9c2-Vector） served as control;（2）Oxidative stress induction and analysis：Cells were treated with 500 μmol/L H2O2 and underwent the following examination：LDH activity in culture medium,cell morphology and intracellular Akt activation ;（3）Role of Akt in the protection of Hsp27 from oxidative damage in H9c2 ： Triciribine, a selective inhibitor of AKT phosphorylation,was introduced in the culture. After pre-treated with Triciribine, H9c2-Hsp27 cells were incubated with 500 μmol/L, then the morphology was observed. Results： （1）H2O2 induced LDH releasing significantly increased in the culture medium both in H9c2-Vector and H9c2-Hsp27（P 〈 0.01 ）. However,compared with H9c2-Vector controls,H2O2 induced LDH release was significantly attenuated in H9c2-Hsp27（P 〈 0.01 ） ;（2）HzOz-iuduced Akt phosphorilation was augmented by Hsp27 overexpression in H9c2-Hsp27, in comparison with H9c2-Vector（P 〈 0.05） ;（3）After Akt phosphorylation was inhibited, the protection of Hsp27 from H2O2 in cell morphology was disappear. Conclusion：Akt activation is involved in the cytoprotection of Hsp27 from oxidative damage in rat cardiac cells.

关 键 词：热休克蛋白27 AKT 氧化应激 

分 类 号：R331.31[医药卫生—人体生理学]