Objective:To observe the effect of Rosiglitazone (RGTZ) on oxygen free radical and biochemical parameters of aged rats,so as to establish a basis for anti-aging study.Methods:The 24-month-old naturally aged SD rats were randomly divided into the control group (CONT),the RGTZ group and the caloric restriction group(CR).The RGTZ group was given intragastric administration of RGTZ (4 mg·kg-1·d-1) and the CR group was given 60% of the diet that of the CONT group.The rats were killed 12 weeks later and the serum malondialdehyde(MDA) content,superoxide dismutase(SOD) activity and the blood biochemistry parameters were examined.Results:The blood glucose (GLU),aspartate transaminase(AST), alamine transaminase(ALT),serum creatinine (SCr),and blood urea nitrogen(BUN) were within the normal range in all groups.Compared with the CONT group,blood cholesterol (CH) in RGTZ group was lower,but with no significant difference.The serum triglyceride(TG) of both RGTZ and CONT groups decreased markedly than those in the CONT group(P＜0.05).The activities of SOD and MDA were improved in RGTZ and CR group compared with the control group.Conclusion:RGTZ can regulate the lipid metabolism and attenuate the oxidative damage in aged rats,indicating its anti-aging effect.