Abstract: ObjectiveTo investigate the protective effects of four antioxidants(N-acetyl cysteineNAC,catalaseCAT,superoxide dismutaseSOD,and mannitol) on oxidative injury of human macrophages induced by uranium dust.MethodsThe cell viability,intracellular reactive oxygen species(ROS) and glutathione(GSH) were determined with methyl thiazolyl tetrazolium(MTT) assay,fluorescence microscopy and chemical/fluorescence emission,respectively.The protective effects of the four antioxidants on uranium dust-induced oxidative injury were evaluated with a combination of MTT and annexin V-FITC/PI staining methods.ResultsUranium dust significantly reduced cell viability in a concentration-and time-dependent manner(P<0.05 for all).Uranium dust-induced apoptosis was characterized by the increare of ROS and the decrease of GSH.After pretreated with NAC,CAT,SOD,and mannitol,the survival rate of human macrophages(89.00±0.95% and 85.87±2.20%) was apparently increased,the concentration of ROS(3.87±0.41 and 6.47±0.99) was decreased and the level of GSH(22.81±2.90 and 21.20±2.85) was increased significantly compared to the cells without NAC or mannitol pretreatment.ConclusionNAC and mannitol are more effective in protecting human macrophages against oxidative injury induced by uranium dust than SOD and CAT.