从SIRT1依赖的信号通路探讨蝉花延缓高血压肾损害的作用机制

Hypertensive renal injury(HRI) is among the first three causes of the end-stage renal disease. Renal interstitial fibrosis (RIF) not only plays a key role in processes of HRI, but also is a phenotype of organ senescence in essential. Under pathological condition, senescence-associated gene SIRT1 relates to renal tubular epithelial cell transdifferentiation,apoptosis and RIF. Compared with cordyceps sinensis, cordyceps cicadae has similar active constituent, but difference flavor and nature. Its sweet flavor and cold-natured characteristic make it fitter to be used under the condition of Yin Deficiency Fire Hyperactivity and arthralgia spasm of kidney collaterals, which is the main cause and pathogenesis of HRI according to the TCM theory. Research result suggested cordyceps cicadae not only has antiaging effect,but also can ameliorate glomerulosclerosis and RIF. According to the theory of Different Diseases in Same Treatment of TCM,we Put forward the hypothesis that cordyceps cicadae could ameliorate HRI by inhibiting epithelial-myofibroblast transdifferentiation and apoptosis in renal tubular epithelial cell via SIRT1and its downstream signal pathway. We will investigate the mechanism of action and specific target point, through which cordyceps cicadae ameliorates HRI, from systemic,organ ,cellular and molecular level in vivo and vitro.

高血压肾损害已经成为终末期肾病的前三位病因。肾间质纤维化在高血压损害进程中扮演者重要角色，而肾间质纤维化实质上是脏器衰老的一种表现。病理状态下衰老相关基因SIRT1与肾小管上皮细胞转分化及凋亡、肾间质纤维化关系密切。中药蝉花的有效成份与冬虫夏草相似，属于优质虫草，但味甘性寒，更符合高血压肾损害阴虚火旺，肾络瘀痹，络息成积的病因病机。研究表明蝉花不仅具有抗衰老作用，而且具有延缓肾小球硬化和肾间质纤维化的作用。根据中医"异病同治"理论，本课题提出了"调控SIRT1及其下游通路，抑制高血压病理状态下肾小管上皮细胞转分化及凋亡是蝉花延缓高血压肾损害的作用机制之一"的假说。拟从体内、体外两方面，在整体、器官、细胞学和分子生物学等不同层面上，探讨蝉花防治高血压肾损害作用机制与具体靶点。

高血压肾损害是终末期肾病的前三位病因。肾小球硬化和间质纤维化在其中扮演重要角色，根据中医“异病同治”理论，本课题提出了“调控SIRT1及其下游通路，抑制高血压病理状态下肾脏固有细胞转分化及凋亡是蝉花延缓高血压肾损害的作用机制之一”的假说。拟以大鼠肾小管上皮细胞为研究对象，从体外实验探讨蝉花防治高血压肾损害作用机制。本课题资助时间为1年，在资助年限内，严格按照计划书内容完成各项指标的检测，顺利结题。我们以AngⅡ剌激下的NRK为研究对象，采用血清药理学研究方法和western-blot、RT-PCR、免疫组化、酶联免疫法等技术，观察空白对照组、AngⅡ对照组、氯沙坦组、白藜芦醇组和蝉花高、中、低剂量组的Sirt1及其下游分子smad7、smad3、p53蛋白及m-RNA表达。同时观察各组NRK细胞内catalase活性，细胞凋亡、转分化以及细胞外基质分泌和调控的情况，采用SPSS20.0统计软件处理，组间差异采用单因素方差分析进行统计分析。研究结果表明，中药蝉花菌丝可以通过上调AngⅡ作用下NRK的Sirt1、smad7蛋白及m-RNA表达和下调smad3、p53蛋白及m-RNA表达，提高NRK的Catalase活性，抑制NRK凋亡和转分化，减少NRK分泌COLⅠ、COLⅢ、FN、LN 、PA-1、TIMP-1，增强NRK分泌PA、MMP-9等而发挥抗肾小管间质纤维化，防治高血压肾损害的作用。