LncRNA PAFLR介导galectin-3促进肺动脉外膜成纤维细胞活化的作用与机制

The activation of pulmonary adventitial fibroblasts (PAFs) plays an important role in vascular remodeling in pulmonary arterial hypertension (PAH). Galectin-3 (Gal-3) has been recently confirmed as a key protein to facilitate the progress of PAH. This protein, with high expression in PAFs, induces the activation of PAFs through inducing oxidative stress. However, the specific mechanism of this process remains unclear. Our pilot study had shown that Gal-3 is able to increase the expression of a lncRNA named PAFLR, and the results further suggest that lncRNA PAFLR controls the trascription of NOX4 via p53. In this study, we plan to establish animal models with genetical modification to overexpress or knockout Gal-3, and to conduct molecular experiments such as chromatin immunoprecipitation. This research is a comprehensive investigation to: 1) demonstrate the importance of Gal-3 to PAFs activation; 2) elucidate the role of PAFLR in Gal-3-induced oxiadtive stress and its consequently PAFs activation; 3) specify the machanism that PAFLR facilitates p53 to bind the promoter of NOX4 to enable downstream effects. If successful, this study will afford a novel therapeutic strategy for vascular remodeling in PAH.

肺动脉外膜成纤维细胞（PAFs）活化是肺动脉高压（PAH）血管重构的重要原因。Gal-3是新近发现诱导PAH发病的重要蛋白，高表达于PAFs,可诱导氧化应激促进 PAFs活化，但其具体机制不明。预实验发现Gal-3可升高LncRNA（命名为PAFLR）的表达，实验结果提示LncRNA PAFLR可能通过p53蛋白调控Nox4的转录。本课题将构建Gal-3转基因及基因敲除等动物模型，通过基因沉默/过表达、染色质共沉淀等方法，探讨：1，Gal-3促进PAFs活化的重要作用；2，LncRNA PAFLR介导Gal-3诱导的氧化应激，促进PAFs活化的作用 ；3，LncRNA PAFLR增强p53蛋白与Nox4上游启动子结合的作用机制。本项目将揭示LncRNA参与介导Gal-3促进PAFs活化的新机制，为PAH肺血管重构的治疗提供新的靶点。

肺动脉外膜成纤维细胞（PAFs）活化是肺动脉高压（PAH）血管重构的重要原因。最近发现，Galectin-3是诱导PAH发病的重要蛋白，可促进PAFs活化，但具体机制不明。本研究通过对PAH患者队列血标本的检测，进一步明确血清Galectin-3是帮助PAH诊断和预测预后效果的生物标志物；通过构建Galectin-3（-/-）转基因小鼠模型并进行实验，进一步明确沉默Galectin-3是改善肺动脉外膜重构以缓解肺动脉高压的有效治疗手段；通过非编码RNA测序和基因沉默/过表达技术，发现Galectin-3上调LncRNA COMP介导的COMP合成以促进PAFs活化，沉默LncRNA COMP可以逆转过表达Galectin-3导致的PAFs异常活化；通过小分子激活剂和基因沉默技术，发现COMP通过激活AKT通路以促进PAFs分泌胶原纤维和迁移增加，但不影响PAFs的增殖水平。综上所述，本研究首次揭示了Galectin-3通过LncRNA COMP-COMP-AKT通路促进PAFs活化的作用和机制，显示出Galectin-3、LncRNA COMP及COMP在PAH诊断和治疗中的转化价值。