Renal protective effect of Tang Shen Ning capsule on diabetic nephropathy rats and the TGF-β_1/Smad7 signal transduction pathway

Objective:To discuss the renal protective effect of Tang Shen Ning capsule on diabetic nephropathy rats(DN rats) induced by streptozotocin(STZ) and the TGF-β1/Smad7 signal transduction pathway.Methods:54 Wistar rats were randomly divided into the follow groups for twice:the normal control group(n=10),the model group(n=15),the irbesartan group(n=15),and the Tang Shen Ning group(n=14).The body weight at an interval of 2 weeks;24 hours urine by collecting every four-week intervals was detected its protein content by coomassie brilliant blue G-250 method.Rats were executed on the 14th week.BUN,Scr,TG,MDA,NO and SOD in the blood serum were tested;histopathological scores and the HE,Mallory staining ways were applied to the kidney tissues.Via immunohistochemistry and in situ hybridization,the renal protein of TGF-β1,Smad7,NF-κB and their mRNA expressions were detected.Results:The general condition of rats could be improved by Tang Shen Ning capsules;the weight of DN rats could be increased and the kidney weight/body weight(KW/BW) could be reduced(P0.01);the 24 hours urinary protein were significantly reduced(P0.01);pathological damage of kidney could be relieved.Compared with the model group,the contents of BUN,Scr,TG,MDA could be obviously reduced(P0.01),and NO,SOD increased apparently(P0.01);the expressions of TGF-β1,NF-κB and their mRNA were significantly reduced(P0.01),while Smad7 and its mRNA could be increased(P0.01).Conclusion:It was found that Tang Shen Ning capsule had the function of protecting kidney,through regulating the expression of the TGF-β1/Smad7 signal transduction pathway.And it could put off the progress of DN rats.