CaSR通过调节TGF-β/Smads信号通路改善糖尿病肾病肾小球硬化及其分子机制研究

肾小球硬化是糖尿病肾病的主要病理特征，具体表现为系膜细胞大量表达细胞外基质蛋白并分泌到细胞外沉积，最终导致肾小球硬化。本课题提出钙敏感受体通过调节TGF-β/Smads信号通路改善高糖以及TGF-β诱导的胞外基质蛋白堆积，从而减轻糖尿病肾病肾小球硬化的假设。体外培养大鼠肾小球系膜细胞，建立高糖与TGF-β诱导的系膜细胞外基质蛋白高表达细胞模型，利用Gd3＋/Ca2+诱导CaSR活化，检测TGF-β/Smads信号通路下游的两个主要的信号分子Smad2/3的磷酸化和胞外基质蛋白的表达，以验证钙敏感受体可以通过调节TGFβ信号通路改善糖尿病肾病肾小球硬化的假说。并通过免疫共沉淀，激光共聚焦和流式细胞术等进一步探讨钙敏感受体改善糖尿病肾病肾小球硬化的机理。建立STZ诱导的糖尿病动物模型，进一步从整体角度探讨钙敏感受体的活化在改善糖尿病肾病肾小球硬化中的作用。

Glomerular sclerosis is the main pathological characteristics of diabetic nephropathy which is characterized by the expression and accumulation of extra cellular matrix (ECM) proteins in mesangial cells (MC). We speculate that CaSR can relieve glomerular sclerosis via antagonizing TGF-β signaling pathway. Aims to verify the hypothesis that the activation of CaSR can inhibit TGF-β/Smads signal pathway and then ameliorate the expression and accumulation of ECM , the mesangial cells were treated with high glucose or TGF-β , then incubated with Gd3＋/Ca2+, the activation of Smad2/3 and accumulation of ECM was tested by Western blot and Real-time PCR. The mechanism of how CaSR improves glomerular sclerosis will be studied by immunoprecipitation, laser confocal and flow cytometry etc. Injecting STZ as an animal model for diabetes to further study the role of CaSR in the development of glomerular sclerosis in diabetic kidney disease.