虫草制剂通过TGF-β/Snail信号通路拮抗糖尿病小鼠肾小管上皮细胞间充质转分化

Cordyceps sinensis attenuates renal epithelial-mesenchymal-transition in diabetic mice vial TGF-β/Snail signal pathway

目的探讨虫草制剂对糖尿病小鼠肾小管上皮细胞间充质转分化(EMT)的影响及转化生长因子β(TGF-β)/锌指转录因子(Snail)信号通路表达情况。方法将18只C57BL/6j小鼠随机分为正常对照组(6只)、糖尿病模型组(12只)。糖尿病小鼠模型制成后,随机分为糖尿病组(6只)(常规饲料喂养正常饮水)和虫草菌液治疗组(6只)(每日给予0.54 g/kg发酵冬虫夏草菌粉提取液)。治疗6周测定各组小鼠体质量、血糖、尿蛋白肌酐比(PCR)等生理指标变化;取肾组织光镜下观察胶原含量;免疫组化或免疫印迹技术检测E-钙粘素(E-cadherin)、α-平滑肌肌动蛋白(α-SMA)、TGF-β1及Snail 1蛋白表达。结果免疫组化及肾组织胶原纤维(Masson)染色显示,与正常对照组比较,糖尿病组及虫草菌液治疗组肾组织E-Cadherin的表达均明显下降,α-SMA的表达均明显上升,胶原成分明显增多,差异均有统计学意义(P<0.05);与糖尿病组比较,虫草菌液治疗组E-Cadherin下降幅度、α-SMA上升幅度、胶原成分均减少,差异有统计学意义(P<0.05)。免疫印迹结果显示,与对照组比较,糖尿病组肾组织TGF-β1及Snail1蛋白表达水平明显上升,差异有统计学意义(P<0.05);与糖尿病组比较,虫草菌液治疗组TGF-β1及Snail1蛋白表达水平下降,差异有统计学意义(P<0.05)。结论虫草制剂可能通过下调TGF-β/Snail信号通路表达抑制糖尿病小鼠肾小管上皮细胞EMT,减轻肾组织纤维化。

Objective To observe the effect of cordyceps sinensis on the renal tubular epithelial-mesenchymal-transition（EMT） in diabetic mice and the expression of transforming growth factor（TGF）-β / zinc finger transcription factor（Snail） signaling pathway. Methods A total of 18 C57 BL /6j mice were randomly divided into the normal control group（ n = 6）,and the diabetic model group（ n =12）. After model establishment,mice in the diabetic model group were randomly divided into the diabetic group（ n = 6,conventionally feeding with normal water）,and the cordyceps sinensis group（ n = 6,feeding with fermentation ectracting solution of cordyceps sinensis in a dose of 0. 54 g / kg）. Changes of physiological indexes,such as the mice body weight,blood glucose and urine protein creatinine ratio（PCR） were measured after 6 weeks of treatment; the renal tissues were observed under light microscope; the expression of collagen content,E-Cadherin,α-SMA,TGF-β1 and Snail 1 protein level in renal tissues were detected by immunohistochemistry or Western blot. Results Immunohistochemical and renal tissue collagen fiber（ Masson） staining showed that,compared with the control group,the expression of E-Cadherin was significantly reduced,the expression of α-SMA was significantly increased,and the ingredient of collagen was significantly increased in the diabetic group and the cordyceps sinensis group,（ P〈0. 05）; compared with the diabetic group,the expression of E-Cadherin increased,α-SMA reduced,and the ingredient of collagen reduced in the cordyceps sinensis group（ P〈0. 05）. Western blot results showed that compared with the control group,protein expression level of TGF-β1 and Snail 1 increased significantly in the renal tissues of diabetic group（ P〈0. 05）; compared with the diabetic group,the protein level of TGF-β1 and Snail 1 reduced in the cordyceps sinensis treatment group（ P〈0. 05）. Conclusion Cordyceps sinensis may attenuate the renal EMT in diabetic mice by down-regulating the expression of TGF-β / Snail signaling pathway,and reduce renal tissue fibrosis in diabetic nephropathy.