益肾汤对糖尿病大鼠肾组织转化生长因子β_1表达的影响

目的观察中药复方益肾汤对实验性糖尿病(DM)大鼠肾脏的保护作用及对转化生长因子-β1(TGF-β_1)表达的影响,探讨其作用机制。方法用链脲菌素诱发、建立糖尿病大鼠模型,通过益肾汤干预治疗,并以血管紧张素Ⅱ受体阻断剂(ARB)缬沙坦作为对照,观察糖代谢(血糖、胰岛素)、大鼠肾功能[包括:肾重/体重、尿总蛋白(24h)、尿白蛋白(24h)、血尿素氮]、肾小球毛细血管基底膜厚度(GBM)、血及肾组织的TGF-β1表达等指标的变化。结果①成功诱发大鼠DM。②各治疗组与糖尿病未治疗组比较均明显降低糖尿病大鼠血糖、尿素氮、尿总蛋白(24h)及微量白蛋白,升高胰岛素水平,抑制肾皮质TGF-β_1表达及GBM的增厚。③相关分析:肾脏TGF-β_1表达量与尿总蛋白(24h)、尿白蛋白(24h)浓度、GBM厚度呈显著正相关。结论益肾汤具有减少尿微量白蛋白排出、血尿素氮浓度、减少肾脏TGF-β_1表达、延缓GBM增厚的作用;益肾汤防治糖尿病肾病(DN)的作用与ARB相仿。益肾汤防治DN及保护肾功能的作用与其降低肾脏TGF-β_1表达有关。

Effects of Yishentang,a traditional Chinese medicine recipe ,on expression of TGF-β1 in kidney of diabetic rats

Objective To investigate the reno-protective effects and underlying mechanism of Yishentang (a traditional Chinese medicine recipe) on the expression of TGF-β1 in kidney of diabetic rats. Methods The diabetic rat models were created by single intraperitoneal injection of streptozocin (STZ) and treated with Yishentang (YS) or Valsartan (an angiotensin receptor blocker, ARB). Changes in the kidney function, glomerular basement membrane (GBM) and expression of TGF-β1 in renal tissue of diabetic rats were recorded and compared with untreated group (DMN group). Results ①Diabetes was successfully induced by injection of STZ in all groups. ②Compared with the DMN group, rats treated with YS or ARB showed significantly lower levels of serum glucose, BUN, 24-hour urine total protein and albumin, TGF-β1 and thinner GBM, but higher level of fasting blood insulin. ③The contents of TGF-β1 in renal tissue was significantly correlated with 24-hour urine total protein, 24-hours urine albumin and mean thickness of GBM. Conclusion Yishentang may reduce albumin excretion in the urine, plasma levels of glucose and BUN, expression of TGF-β1, and delay the thickening of GBM in diabetes rats. The prophylactic and therapeutic effects of Yishentang were comparable to ARB, which was at least in part attributable to its down-regulation on TGF-β1 expression in the kidney.