Antidiabetes nephropathy effect of resveratrol via inhibition of TGF-β1/Smad2 signal pathway

AIM To investigate the effect of resveratrol on diabetic nephropathy(DN) and the expression of TGF-β1/Smad2 signal pathway in the kidney of DN rats.METHODS Twenty-nine male SD rats were randomly divided into control group(n = 5),model group(n = 12) and resveratrol group(n = 12).The DN model rats in the model group and resveratrol group were induced by injecting streptozotocin 65 mg.kg-1.The rats in the resveratrol group were given resveratrol 5 mg.kg-1,ig,qd for 28 days.The other rats in the control group and model group were given the same volume of normal saline.Fasting blood glucose and body weight of all the rats were monitored.BUN and kidney index were detected.Then,the morphological changes of the kidney were observed by HE,PAS,MASSON staining,respectively.The mRNA expression of TGF-β1,Smad2,CTGF and FN were examined by real-time PCR,respectively.RESULTS Compared with the normal control group,streptozotocin significantly induced weight lost and kidney structure disordered,and increased the value of kidney index,fasting blood glucose and BUN of the model group(P 0.01).And the mRNA expressions of TGF-β1,Smad2,CTGF and FN in kidney tissues of the model group were up-regulated(P 0.05 or P 0.01).Compared with the model group,weight lost and kidney structure,and the value of kidney index,fasting blood glucose and BUN were improved significantly in the resveratrol group(P 0.01).And the mRNA expressions of TGF-β1,Smad2,CTGF and FN in kidney tissues were down-regulated(P 0.05 or P 0.01).CONCLUSION Inhibition of TGF-β1/Smad2 pathway might be responsible for the renal protective effects of resveratrol on DN induced by streptozotocin.