辛伐他汀对糖尿病大鼠肾脏TGF-β系统的影响

目的：探讨辛伐他汀对糖尿病大鼠肾脏转化生长因子β1（TGF-β1）和转化生长因子βⅡ型受体（TβⅡR）表达的影响及其肾脏的保护机制。方法：SD大鼠单次腹腔注射55mg/kg链脲佐菌素(STZ )制备糖尿病大鼠模型。糖尿病大鼠随机分成糖尿病组、辛伐他汀治疗组［4mg/(kg·d)］和正常对照组。用免疫组织化学，RT-PCR和Western印迹法检测16周大鼠肾脏TGF-β1和TβⅡR表达的变化。结果：与正常对照组比较，糖尿病组和辛伐他汀治疗组TGF-β1和TβⅡR表达均增加（P<0.05）。治疗组TGF-β1和TβⅡR表达显著低于糖尿病组（P<0.05）。结论：辛伐他汀可以通过下调TGF-β1和TβⅡR的表达，抑制TGF-β系统信号通路的过度激活，减少糖尿病大鼠尿蛋白，延缓肾脏病变的进展。

Effects of simvastatin on TGF-β system of diabetic rat kidneys

OBJECTIVE: To investigate the effects and mechanism of renal benefit of simvastatin on diabetic rat kidneys. METHODS: Twenty STZ-induced SD rats and 10 normal rats were assigned to diabetic rat (DM) group, simvastatin 4 mg/( kg x d) ] treatment (S) group and normal control (C) group. Immunohistochemistry, RT-PCR and western-blot were employed to examine the changes of the mRNA and protein expression of TGF-beta1 and Tbeta II R in the kidneys of the rats. RESULTS: Compared with the normal control group, both the mRNA and protein expression of TGF-beta1 and Tbeta II R in the diabetic rat group and treatment group were significantly increased (P < 0.05). Compared with the diabetic rat group, simvastatin could markedly decrease the mRNA and protein expression of TGF-beta1 and Tbeta II R (P < 0.05). CONCLUSION: Simvastatim may play a protective role in the diabetic kidneys by down-regulating TGF-beta1 and Tbeta II R and inhibiting the TGF-beta signal pathway.