The Effects of Thiazolidinediones on the Serum Substance P and Oxidative Stress,Skin Changes in Diabetic Rats

Objective To study the effects of Thiazolidinediones on serum substance P,oxidative stress inflammatory factors and skin changes in diabetic rats.Methods A diabetic rat model was induced by the streptozotocin(STZ)to 10 week-old male Wistar rats.The rats were divided into insulin-treated diabetic group(DI group,n=13),rosiglitazone treatment diabetic group(DR group,n=13),diabetic control group(DC group,n=13),and normal control(C group)(n=13).Heart blood of rats in each group at the end of 16 weeks were collected to measure level of TNF-α,IL-6,C-RP,SOD,and P substance The skin biopsy were performed for pathological examination.Results The levels of IL-6,TNF-α and C-RP of all the diabetic model groups were significantly higher than those of the normal group(P0.05),No difference was observed in DI and DR groups compared with the normal control group;the SOD and SP level in diabetic group was significantly lower than that in the normal group(P0.01),the SOD and SP levels were significantly increased in insulin and rosiglitazone groups compared with Diabetes Group(P0.01,P0.05).The skin of pathogenic diabetic rats became obviously thinner with keratinocytes significantly reduced,even single-layer arrangement,reduction of dermal collagen and fat tissue loss in DC group at 16th week.No such histological changes were observed in the skin of diabetic rats from DI and DR groups.Conclusion Thiazolidinediones can reduce serum inflammatory mediators,increased SOD,substance P levels and help prevent change of skin lesions in diabetic rats.