Effects of Tangshenping Capsule on the Renal Protection and Expressions of TGF-β1 and mRNA in Streptozotocin induced Diabetic Nephropathy Rats

Abstract

This work aimed to observe the effects of “Tangshenping Capsule” on the renal protection and expressions of TGF-β₁ protein and mRNA in streptozotocin-induced diabetic nephropathy (DN) rats. 50 SD rats were randomly divided into the normal control group (n=10) and the model group (n= 40). 55 mg/kg one-time intraperitoneal injection of streptozotocin was used to induce diabetes model rats. 72 hours after injection, rats with blood glucose higher than 16.7 mmol/L and urinary glucose higher than 4+, were selected as diabetes rats. Then those modeling success rats were re-randomized into the model group, the irbesartan group and the Tangshenping capsule group. Body weight was weighed every week, 24 h divla cage urine was collected at week 4, 8 and 12 after streptozotocin injection, and 24 h urine protein was detected. All rats were sacrificed after 12 weeks treatment. Blood urea nitrogen (BUN), serum creatinine (Scr), and triglyceride (TG) were detected in blood serum. Pathological changes of renal tissue were observed by Mallory staining, TGF-β₁ protein and mRNA expression of the renal tissue were detected by immunohistochemistry and in situ hybridization. Rats of the model groups had different levels of feeding and sleeplessness, slow activity, weight loss, 24 h urinary protein increase, and abnormal blood biochemical indicators, while the rats from the irbesartan and the Tangshenping capsule group were all improved in different degrees in the above aspects, and the Tangshenping capsule group was superior to the irbesartan group; the model group showed obvious DN pathological renal changes; in the normal group and the treatment groups, renal tubular epithelial cells and interstitial cells had mild TGF-β₁ and mRNA expression, while there was strong expression in the model group. The TGF-β₁ and mRNA expression in the Tangshenping capsule group was significantly reduced (P <0.05) compared to the model group. Therefore “Tangshenping capsule” may prevent DN via regulating TGF-β₁ and mRNA balance.