基于CaN/NFAT信号通路-肺动脉重构研究蛇床子素抗肺动脉高压作用机制

Inflammatory and immunity play an important role in the pathogenesis of pulmonary artery hypertension (PAH). The CaN/NFAT signaling pathway activates immune cells to secrete inflammatory factors and acts on the distal pulmonary artery to cause pulmonary artery remodeling. Osthole (Ost) is a coumarin compound extracted from cnidium of umbelliferae. Our previous studies found that Ost had play a role in the prevention and treatment of PAH, but its mechanism remains to be studied and clarified. In the preliminary experiments, Ost was found to inhibit the expression of NFATc2 nuclear protein in pulmonary artery. Therefore, it is speculated that inhibition of CaN/NFAT signaling pathway and activation of immune cells may be a new mechanism of Ost to improve pulmonary artery remodeling. Therefore, we plan to use the MCT-induced PAH rat model to further study the relationship between the effect of Osthole on pulmonary artery remodeling and CaN/NFAT signaling pathways and analyze their correlation. Then the primary cultured rat PASMC or macrophage RAW264.7 were used, through transfection of NFAT overexpression by adenoviral vectors and various tool medicines to further study the molecular mechanism of CaN/NFAT signaling pathway in Ost pulmonary artery remodeling, in order to further reveal the basic pharmacological effects of Ost anti-PAH. The aim is to provide basic pharmacological research data for Ost anti-PAH.

炎症免疫在肺动脉高压（PAH）发病中起重要作用。CaN/NFAT信号通路可激活免疫细胞分泌炎症因子并作用于远端肺动脉引起肺动脉重构。蛇床子素(Ost)是伞形科蛇床子中提取的香豆素类化合物。本项目组前期研究发现Ost有防治PAH的作用，但其机制仍待研究阐明。预实验中发现Ost能抑制肺动脉组织NFATc2核蛋白表达。故推测抑制CaN/NFAT信号通路和免疫细胞的激活可能是Ost改善肺动脉重构的新机制。因此项目组利用MCT诱导的PAH大鼠模型，深入研究Ost干预肺动脉重构作用与CaN/NFAT信号通路的关系并分析其相关性。然后分别以原代培养的大鼠PASMC或巨噬细胞株RAW264.7，通过腺病毒载体转染NFAT过表达技术并借助各种工具药，深入研究CaN/NFAT信号通路在Ost干预肺动脉重构中的分子机制，进一步揭示Ost抗PAH的基础药理作用。本项目旨在为Ost抗PAH提供基础药理学研究依据。

炎症免疫在肺动脉高压（PAH）发病中起重要作用。CaN/NFAT信号通路可激活免疫细胞分泌炎症因子并作用于远端肺动脉引起肺动脉重构。蛇床子素（Ost）是伞形科蛇床子中提取的香豆素类化合物。本项目组前期研究发现Ost有防治PAH的作用，但其机制仍待研究阐明。本研究中在体实验利用野百合碱（MCT）诱导的PAH大鼠模型，离体实验利用PDGF-BB刺激的PASMCs，进一步深入研究Ost抗PAH的作用机制，并借助多种工具药，分析炎症免疫反应以及CaN/NFAT、eNOS/PKG-1、Smads/p38等信号通路在Ost抗肺小动脉重构中所发挥的作用，进一步揭示Ost抗PAH的分子药理学机制。研究首先确证了Ost具有抗MCT所致大鼠PAH的作用，并发现其机制为：① Ost通过抑制CaN/NFATc2信号通路，抑制PASMCs中NFATc2核蛋白表达，减少IL-1β、IL-6、MCP-1、TNF-α，抑制炎症免疫反应，继而抑制PASMCs增殖、促进PASMCs凋亡，减轻肺小动脉重构；② Ost通过上调eNOS/PKG-1信号通路，抑制PASMCs增殖、促进PASMCs凋亡，减轻肺小动脉重构；③ Ost通过下调Smads/p38信号通路，调控细胞周期，减少PASMCs增殖，抑制肺小动脉重构；④ Ost通过上调ASK1，促进PASMC凋亡，抑制肺小动脉重构；⑤ 此外，我们还发现Ost通过上调eNOS/PKG-1通路及抑制内质网应激，发挥抗MCT所致大鼠右心室重构的作用。以上发现为Ost后续用于PAH及其并发症的防治提供基础药理学依据。