Snail1调控STOML2的表达在糖尿病肾病EMT发生中的作用及机制研究

Diabetic nephropathy is a common and refractory microvascular complications of diabetes. It is known that renal tubular epithelial cells - mesenchymal transition (Epithelial-mesenchymal transition, EMT) plays a key role in renal interstitial fibrosis in diabetic nephropathy. However, the mechanism of EMT is unclear in DN process. In our previous study, we found that the expression of Snail1 was high and specificity in renal tissues of diabetic nephropathy, and upregulated expression of Snail1 can promote EMT in renal tubular epithelial cells. We used proteomics to screen and identify that STOML2 was upregulated expression in cells stably overexpressed Snail1, and we used biological information to predict Snail1 binding sites in the STOML2 promoter region. So we proposed Snail1 promote EMT process by upregulating STOML2. Next, we intend to adopt CHIP-PCR and EMSA methods to confirm that Snail1 transcriptionally activate STOML2 expression, then promote EMT occurs. The study is expected to reveal a new mechanism of EMT in diabetic nephropathy, and provide new ideas and methods for the prevention and treatment of diabetic nephropathy.

糖尿病肾病（DN）是糖尿病常见且难治的微血管并发症。已知肾小管上皮细胞-间质转化（EMT）是DN肾间质纤维化发生发展的核心环节，但目前DN过程中EMT发生的机制尚不明确。我们在前期研究中，发现Snaill在DN肾组织中呈特异性高表达，上调表达Snail1能诱导肾小管上皮细胞EMT发生，进一步通过蛋白质组学筛选鉴定出STOML2在稳定过表达Snail1的细胞中表达明显升高，并且应用生物信息学预测到STOML2启动子区域存在Snail1的结合位点。我们提出Snail1介导 EMT的可能机制：即DN时Snail1通过转录激活STOML2表达并促进EMT发生。本项目拟采用CHIP-PCR、EMSA等方法证实Snail1转录激活STOML2，并探讨这一事件对EMT的重要性和意义。本研究有望揭示一种新的糖尿病肾病EMT发生机制，为临床防治糖尿病肾病提新的思路和方法。

糖尿病肾病（Diabetic nephropathy, DN）是糖尿病常见且难治的微血管并发症。现有研究表明，肾小管间质纤维化是DN进展为ESRD的主要病理基础，上皮-间质细胞转化（Epithelial- mesenchymal transition，EMT）被认为是肾间质纤维化发生发展的核心环节之一。Snail1是诱发DN肾纤维化的关键性因子，可以启动肾小管上皮细胞EMT的发生发展。.本研究发现Snail1在2型DN肾组织中呈特异性激活高表达，通过双向电泳筛选Snail1高表达及对照细胞的差异表达蛋白，验证发现Snail1能上调STOML2的蛋白及mRNA水平，遂提出进一步研究Snail1在糖尿病肾病EMT发生中的作用及机制，为阐明糖尿病肾病肾纤维化发生的分子机制提供实验依据。.本研究重要研究结果：.1．Snail1在DN肾组织中表达明显上调，稳定高表达Snail1可诱导肾小管上皮细胞发生EMT。.2. 双向电泳筛选Snail1高表达及对照细胞的差异表达蛋白，验证结果显示Snail1能上调STOML2的蛋白及mRNA水平。.3. 生物信息学预测分析显示STOML2基因启动子区域有1个推定的Snail1结合位点，通过荧光素酶报告基因分析及ChIP实验充分证实Snail1能直接转录调控STOML2基因的表达。.4. 肾小管上皮细胞特异性敲除Snail1基因能减轻糖尿病肾病的纤维化程度。进一步在动物体内下调 STOML2的表达，能减轻糖尿病肾病小鼠的血糖，血肌酐，尿白蛋白/肌酐及肾脏纤维化程，具有治疗作用。