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

Objective:To investigate the mechanisms of the cytoprotection of Heat shock protein27(Hsp27) from H2O2-induced damage in rat cardiac cells. Methods:①Rat 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;②Oxidative 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;③Role 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:①H2O2 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);②H2O2-induced Akt phosphorilation was augmented by Hsp27 overexpression in H9c2-Hsp27,in comparison with H9c2-Vector(P 0.05);③After 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.