N-acetyl-L-cysteine protects PC12 cells against injuries induced by chemical hypoxia

Objective To investigate the protective effect of reactive oxygen species(ROS) scavenger,N-acetyl-L-cysteine(NAC),against PC12 cells from injuries induced by chemical hypoxia.Methods PC12 cells were treated with cobalt chloride(CoCl2),a chemical hypoxia-mimetic agent,to establish the chemical hypoxia-induced PC12 cells injury model.NAC was added into cell medium 60 min prior to CoCl2 exposure.The cell viability was evaluated using cell counter kit(CCK-8).Morphological changes in apoptotic PC12 cells were detected by Hoechst 33258 staining and photofluorography.Mitochondrial membrane potential(MMP) was determined by Rhodamine123(Rh123) staining followed by photofluorography;the expression of cleaved caspase-3 was detected by western blot.Results Exposure of PC12 cells to 600 μmol/L CoCl2 for 24 h resulted in significantly cell injuries,evidenced by a decrease in cell viability,increases in apoptotic cells,and cleaved caspase-3 expression as well as loss of MMP.Pretreatment with NAC at the concentration of 500 μmol/L 60min before CoCl2 exposure inhibited CoCl2-induced PC12 cells injuries,leading to a significant increase in cell survival rate,decreases in apoptotic percent of PC12 cells and cleaved caspase-3 expression.Meanwhile,NAC attenuated the ameliorate MMP in PC12 cells.Conclusions NAC significantly protects PC12 cells against injury induced by chemical hypoxia,which is associated with decreasing caspase-3 activation and ameliorating MMP.