下丘脑室旁核中肾素血管紧张素系统激活在子痫前期发病机制中的作用研究

Previous studies and our experimental results suggest that PVN plays a critical role in the regulation of blood pressure and target organ injury in patients with preeclampsia. In this study, we will for the first time investigate the central regulatory mechanisms of preeclampsia. Starting from preeclampsia patients and placental trophoblast cells, we focus on the exosome-renin agiotensin system (RAS)-PVN in the pathogenisis of preeclampsia at the level of in vivo, organ, cell and molecular: 1) Analyzing PVN in preeclampsia patients with functional magnetic resonance imaging and the components of exosomes from placenta, we try to find other noninvasive examination methods and new biomarkers for preeclampsia diagnosis; 2) Using conditional Agtrla knockout rats and bilateral PVN infusion technique, we will verify that the activation of RAS and its downstream signaling are key factors in the development of preeclampsia; 3) By establishing trophoblast cell line with stable expression of near infrared fluorescent protein and using small animal imaging and protein phosphorylation antibody chip, we will confirm that exosomes from trophoblast cell promote the occurrence and development of preeclampsia through activation of RAS and explore its related mechanisms in vivo and in vitro. This study will add new insights into the pathogenesis of preeclampsia from the central point of view and provide theoretical basis for the clinical diagnosis and treatment of preeclampsia.

国内外研究与本实验室的相关结果提示下丘脑室旁核（PVN）神经元活化可能是介导子痫前期（PE）患者血压升高及靶器官损害的关键。本项目首次从中枢调控角度出发，以PE患者和胎盘滋养细胞为切入点，围绕外泌体-肾素血管紧张素系统(RAS)-PVN，从整体、器官、细胞和分子四个层面展开研究：1）分析PE患者PVN磁共振功能成像和胎盘来源外泌体组分，为PE的临床诊断提供新的无创辅助检查手段和生物标志物; 2）采用Agtr1a基因条件敲除大鼠，结合双侧PVN插管术，初步证实PVN中RAS组分及其下游信号的激活是介导PE发生发展的关键; 3）构建稳定表达近红外荧光蛋白的滋养细胞株，结合小动物活体成像和蛋白磷酸化抗体芯片, 在细胞和整体水平证实滋养细胞外泌体通过RAS活化PVN神经元促进PE发生发展，并探索其分子机制。本项目从中枢角度进一步完善PE发病机制，可望为PE的临床诊治提供新的理论依据和药物干预靶点。

子痫前期(Preeclampsia，PE)是妊娠期特发的全身性疾病，多在妊娠20周以后发病。临床表现以高血压、蛋白尿为特征，并伴有全身多脏器的损害，其基本病理生理改变是全身小动脉的痉挛性收缩。目前绝大多数学者都是从胎盘或胎儿角度探究PE的发病机制，认为PE与滋养细胞功能障碍、子宫螺旋动脉重铸不足、母胎界面免疫细胞失衡有关，相关研究结果支撑了目前PE的临床治疗策略，但是目前的治疗手段不能从根本上解决问题，引产仍然是重症患者唯一的选择。本项目从中枢角度出发，以子痫前期患者和胎盘滋养细胞为切入点，围绕外泌体-RAS-PVN，为子痫前期发病机制的研究打开一个全新的突破点。初步证实PVN中RAS激活与子痫前期患者血压升高和尿蛋白含量增加呈完全正相关，抑制RAS组分能够显著改善血压、蛋白尿以及其它靶器官损害；初步证实子痫前期大鼠迷走神经张力显著降低，改善迷走神经能够有效抑制PVN中RAS活化，从而改善PE临床症状；建立外泌体分离纯化方法，有效提升提取效率；证实PE患者来源外泌体能够通过活化滋养细胞和内皮细胞促进子痫前期的发展，采用ACh干预能够有效抑制PE危险因素对滋养细胞和内皮细胞的损伤。