The effects of pioglitazone on oxidative stress of the kidneys of diabetic rats

Objective: To study the effects of pioglitazone on oxidative stress of the kidneys of diabetic rats.Methods: The diabetic model was induced by streptozotocin.The rats were divided into 4 groups of 10 rats each: control group,control rats receiving pioglitazone,diabetic group and diabetic rats receiving pioglitazone.Pioglitazone was given at a dose of 10 mg·(kg~(-1)·d~(-1)) once daily.Blood glucose,body weight(BW),kidney weight(KW),ratio of kidney weight to body weight(KW/BW),24 h urinary protein content were measured.The levels of malondialdehyde(MDA),total antioxidative capacity(T-AOC) and glutathione(GSH) in renal tissue as well as activities of Cu,Zn superoxide dismutase(Cu,Zn-SOD),catalase(CAT),glutathione peroxidase(GSH-Px) and glutathione reductase(GR) in renal tissue were determined.Results: Increased KW/BW,24 h urinary protein content were significantly attenuated by treatment with pioglitazone(P 0.01),but pioglitazone did not affect the level of plasma glucose in diabetic rats(P0.05).Elevated MDA level and CAT activity in diabetic renal tissue as well as(decreased) levels of T-AOC,GSH and activities of Cu,Zn-SOD,GSH-Px,GR in diabetic renal tissue were also remitted by pioglitazone(P0.05,P0.01).Conclusion: This study shows that the kidneys of diabetic rats undergo an obvious oxidative stress.Pioglitazone treatment can to some extent protect kidneys from oxidative injury by diabetes,which is(independent) of its glucose-reducing effect.