靶向Hint1调控肺上皮-间质转化防治肺纤维化的研究

Novel drugs such as pifernidone and nintedanib that targeting critical mechanisms have shed light on the treatment of pulmonary fibrosis. TGF-β1 and Wnt/β-catenin signaling pathway coverge to induce epithelial-mesenchymal transition (EMT), one of the key pathological mechanisms in pulmonary fibrosis by which lung fibroblasts are excessively produced. Our previous researches reveal that Hint1 protein is down-regulated in pulmonary fibrosis, and that Hint1 gene transfer inactivates both Wnt and TGF-β1 signaling pathway, which in further inhibits TGF-β1-induced EMT in A549 alveolar epithelial cells. These data in sum suggest that Hint1 might serve as an EMT inbihitor as well as a novel therapeutic target for pulmonary fibrosis. In this study we will investigate the impact and mechanisms of Hint1 on alveolar epithelial cells both in vivo and in vitro. Firstly, Hint1 gene would be silenced or overexpressed in MLE-12 mouse lung epithelial cells, and LV-Hint1 lentivirus would be introduced into an animal model of pulmonary fibrosis, then the expression of Hint1 would be analyzed in specimens of pulmonary fibrosis patients. This study will elucidate the possible mechanism of Hint1 in pulmonary EMT, and provide novel therapeutic targets for pulmonary fibrosis.

吡非尼酮和尼达尼布靶向作用于肺纤维化的多种核心信号分子，为肺纤维化的治疗打开了全新局面。TGF-β1和Wnt信号通路协同诱导肺泡上皮-间充质转化(EMT)，是肺纤维化中成纤维细胞的重要来源。前期研究发现：肺纤维化中Hint1蛋白表达下调，过表达Hint1蛋白能阻断TGF-β1和Wnt信号通路，进而阻抑A549细胞的EMT过程。这提示Hint1有调控肺上皮EMT作用，有望成为肺纤维化的又一治疗靶点。本项目中我们将首先在MLE-12小鼠肺泡上皮细胞转染及沉默Hint1基因，并将LV-Hint1慢病毒颗粒静脉注入肺纤维化小鼠模型，同时研究Hint1在人肺纤维化中的表达，观察Hint1对体内和体外肺上皮EMT的作用和机制，预期为肺纤维化新的治疗靶点提供实验依据。

肺纤维化患者预后极差。多靶点抗纤维化药物是目前肺纤维化的药物开发策略之一，而Hint1可能是靶点之一，在实验性肝纤维化中显示出治疗作用。研究者假设Hint1可能抑制TGF-beta1和Wnt信号通路，有抗肺纤维化作用。根据研究计划，本课题主要对Hint1在肺纤维化中的作用进行了探讨。结果显示：在分子和细胞层面，Hint1可抑制促纤维化相关信号分子的表达，抑制EMT和细胞表型转化。在组织和器官层面，Hint1在肺纤维化中表达明显降低，过表达Hint1则可抑制博莱霉素肺纤维化。在此基础上，本研究进一步探讨了Hint1可能的作用机制。已有论文和专利发表，另有一篇论文已完成，在投稿阶段。