白芍总苷对糖尿病大鼠肾脏足细胞相关蛋白Nephrin表达的影响及机制

Effect of total glucosides of paeony on the expression of Nephrin and its mechanism in the kidney of diabetic rats

目的探讨白芍总苷对糖尿病大鼠肾脏足细胞相关蛋白Nephrin蛋白表达的影响及机制。方法建立链脲佐菌素诱导的大鼠糖尿病模型,将模型大鼠随机分糖尿病组与TGP(50,100,200mg·kg-1.d-1灌胃)给药组,另设正常对照组。8wk末检测大鼠血糖、24h尿白蛋白排泄率(AER)变化,应用间接免疫荧光法检测肾组织Nephrin分布、West-ern杂交检测肾组织Nephrin、肿瘤坏死因子-α(TNF-α)与NF-κB-p65蛋白表达。结果模型组大鼠24hAER明显高于给药组,TGP治疗组大鼠24hAER明显减低。免疫荧光显示对照组肾小球Nephrin呈线状均匀分布;糖尿病组表达明显减少、呈颗粒状不均匀分布;TGP治疗组Nephrin表达增加,呈线状及颗粒状分布。Westernblot显示模型组肾组织Nephrin蛋白表达明显低于对照组,TGP治疗组表达增加;模型组肾组织TNF-α与NF-κB-p65蛋白表达明显高于对照组,TGP治疗组呈剂量依赖性降低它们的表达。结论TGP降低糖尿病大鼠尿蛋白机制可能部分与增加肾小球Nephrin表达有关。

Aim To investigate the effect of total glucosides of paeony （TGP） on the expression of Nephrin and its mechanism in the kidney of diabetic rats. Methods Diabetes was induced with streptozotocin, and TGP（ 50 ,100 ,200 mg·kg^-1·d^-1） was orally administered once a day for 8 wk. Blood glucose,24 hours urinary albumin excretion rate （AER） were measured. The expression of Nephrin, tumor necrosis factor-a （TNF-a） and NF-kB-p65 protein was determined by immunoinfluorescence or Western blot. Results Elevated AER was markedly attenuated by TGP treatment. （ P 〈 0. 05 ）. There was a finely dotted linear epithelial staining of Nephrin in control group glomeruli. In contrast, the staining of glomeruli from untreated diabetic rats was attenuated, more dispersed and clustered, this diabetic-induced loss of glomerular Nephrin expression was largly prevented in TGP-treated diabetic rats. Western blot analysis showed that the expression of Nephrin protein was reduced in the kidney of diabetic rats, but significantly increased with TGP （ P 〈 0.01, P 〈 0.05）. The expression of TNF-α and NF-kB-p65 protein in the kidney was significantly increased in diabetic rats, which were all significantly inhibited by TGP treatment （P 〈 0.01 ）. Conclusions TGP can decrease AER in diabetic rats. The mechanism may be at least partly correlated with upregulation of the expression of Nephrin in the kidney.