Overexpression of heat-shock proteins B1 protected rat cardiac cell line H9c2 from H_2O_2-induced oxidative damage

Objective To determine the effect of mitochondria on the protection of heat-shock proteins B1(HSPB1) from oxidative damage in rat cardiac cell.Methods HSPB1 gene-transfected rat cardiomyocytes cell line H9c2 (HSPB1 H9c2) and empty vector transfected H9c2 (control) were established,and treated by 0-1000μmol/L H_2O_2 for 2h.And then the cell morphology, mitochondrial membrane potential and endogenous reactive oxygen species (ROS) were detected. Results (1)HSPB1 inhibited the morphological changes induced by H_2O_2 markedly.(2)HSPB1 inhibited the loss of mitochondrial membrane potential induced by H_2O_2.Following the stimulation of 0,75,150,300,500,1000μmol/L H_2O_2,mitochondrial membrane potential in HSPB1 and control H9c2 cells were (10.0±0.11)vs (7.01±0.26),(9.11±0.17)vs (6.05±0.19),(7.69±0.28)vs (5.14±0.28),(6.95±0.13)vs (4.66±0.11),(6.61±0.20)vs (1.85±0.35),(6.60±0.05)vs (1.19±0.01),respectively (all P0.01).(3) HSPB1 significantly inhibited endogenous ROS generation induced by H_2O_2.The fluorescence density in HSPB1 and control cells after 0,75,150, 300,500,1000μmol/L H_2O_2 stimulations were (5527±248)vs(5964±387),(6719±336)vs(8528± 411),(6469±160)vs(7795±136),(7042±12)vs(7591±203),(6148±208)vs(6911±136),(5468± 546)vs(6822±371),(all P0.05),except 0μmol/L group(P0.05).Conclusions HSPB1 protects rat cardiomyocytes cell line(H9c2) from oxidative damage,which suggests that stabilization of mitochondrial membrane potential and the decreased endogenous reactive oxygen species after oxidative stress may be involved in the protection of HSPB1 against oxidative stress in H9c2.