ObjectiveTo investigate the protective effects of carboxyfullerene C3 against γ-ray irradiation-induced injury in BALB/c mice. MethodsBALB/c mice were intraperitoneally injected with carboxyfullerene C3 (100 mg/kg) 0.5 h before whole-body γ-ray irradiation at 6.0 Gy (LD50) and 7.2 Gy (LD90), with the dose rates being 1.0 Gy/min. The survival rate, average survival period of dead animals, and leukocyte count were observed 30 days after irradiation. The serum concentrations of superoxide dismutase (SOD), glutathione(GSH), and malondialdehyde (MDA) were examined by ELISA 4 h after γ-ray irradiation. The numbers of exogenous spleen colony-forming units (CFU-S) and in vitro colony-forming units of granulocyte and monocyte (CFU-GM) in mice receiving different regimens of γ-ray irradiation were calculated under microscope. ResultsCarboxyfullerene C3 significantly increased the survival rate of mice on the 30th day after irradiation(P<0.01), but it failed to prolong the average survival time of the dead animals after irradiation. Carboxyfullerene C3increased the serum levels of SOD and GSH(P<0.01), and decreased serum MDA level(P<0.01). Besides, carboxyfullerene C3 also significantly increased the peripheral leukocyte count(P<0.01), and promoted the CFU-S and CFU-GM counts(P<0.01). ConclusionWater-soluble carboxyfullerene C3 has satisfactory protective effect against γ-ray irradiation-induced injury in mice.