Antagonistic effect of N-acetyl cysteine and caspase-3 inhibitor on apoptosis of 293 cells induced by cadmium

ObjectiveTo study the effects of-Nacetyl cysteine and caspase-3 inhibitor on apoptosis of transformed human embryonic kidney 293 cells induced by cadmium for exploring the role of oxidative damage and caspase pathway played in the apoptosis.MethodTransformed human embryonic kidney 293 cells were incubated with 0,20,40,80,120,200μmol/L CdCl2respectively for 0,3,6,12 and 24 h.The cells in groups of NAC and caspase-3 inhibitor(Z-DEVD-fmk) were pre-treated with 2.5,5.0,10.0 mmol/L NAC and 0.1,1.0,10μmol/L Z-DEVD-fmk for 24 h and 1 h respectively before 24 h incubation with 40μmol/L CdCl2.Using MTT method for measuring the relative survival rate and flow cytometry annexin-V/PI double stain method for measuring the apop-tosis percentage of test cells.ResultThe results showed that the cellular relative survival rate was time and dose dependent upon the dose of cadmium.Compared with 0μmol/L cadmium,the apoptosis rate increased obviously in the incubating cells with 40,80,120,200μmol/L cadmium(P0.01).Both NAC(an antioxidant agent) and Z-DEVD-fmk(a selective inhibitors of caspase-3),might significantly suppress cadmium-induced cell apoptosis(P0.01).ConclusionAntioxidant agent and selective inhibitor of caspase-3 may suppress the apoptosis induced by Cd and oxidative stress and caspase-3 might be involved in Cd-induced apoptosis.