Shen Tingting, Wang Na, Yu Xiufeng, Shi Jiucheng, Li Qian, Zhang Chen, Fu Li, Wang Shuang, Xing Yan, Zheng Xiaodong, Yu Lei, Zhu Daling
Department of Biopharmaceutical Sciences, College of Pharmacy, Harbin Medical University (Daqing), Daqing, China.
Biopharmaceutical Key Laboratory of Heilongjiang Province, Harbin Medical University, Harbin, China.
J Cell Biochem. 2015 Sep;116(9):1993-2007. doi: 10.1002/jcb.25154.
Pulmonary arterial hypertension (PAH) is a lethal disease characterized by pulmonary vascular obstruction due in part to excessive pulmonary artery endothelial cells (PAECs) migration and proliferation. The mitochondrial fission protein dynamin-related protein-1 (DRP1) has important influence on pulmonary vascular remodeling. However, whether DRP1 participates in the development and progression of pulmonary vascular angiogenesis has not been reported previously. To test the hypothesis that DRP1 promotes the angiogenesis via promoting the proliferation, stimulating migration, and inhibiting the apoptosis of PAECs in mitochondrial Ca(2+)-dependent manner, we performed following studies. Using hemodynamic analysis and morphometric assay, we found that DRP1 mediated the elevation of right ventricular systemic pressure (RVSP), right heart hypertrophy, and increase of pulmonary microvessels induced by hypoxia. DRP1 inhibition reversed tube network formation in vitro stimulated by hypoxia. The mitochondrial Ca(2+) inhibited by hypoxia was recovered by DRP1 silencing. Moreover, pulmonary vascular angiogenesis promoted by DRP1 was reversed by the specific mitochondrial Ca(2+) uniporter inhibitor Ru360. In addition, DRP1 promoted the proliferation and migration of PAECs in mitochondrial Ca(2+)-dependent manner. Besides, DRP1 decreased mitochondrial membrane potential, reduced the DNA fragmentation, and inhibited the caspase-3 activation, which were all aggravated by Ru360. Therefore, these results indicate that the mitochondrial fission machinery promotes migration, facilitates proliferation, and prevents from apoptosis via mitochondrial Ca(2+)-dependent pathway in endothelial cells leading to pulmonary angiogenesis.
肺动脉高压（PAH）是一种致命性疾病，其特征在于部分由于过度的肺动脉内皮细胞（PAECs）迁移和增殖导致肺血管阻塞。线粒体裂变蛋白动力相关蛋白1（DRP1）对肺血管重塑具有重要影响。然而，DRP1是否参与肺血管生成的发展和进程此前尚未见报道。为了验证DRP1通过以线粒体Ca(2+)依赖的方式促进PAECs增殖、刺激迁移和抑制凋亡来促进血管生成这一假说，我们进行了以下研究。通过血流动力学分析和形态测定，我们发现DRP1介导了缺氧诱导的右心室系统压力（RVSP）升高、右心肥大以及肺微血管增加。DRP1抑制可逆转缺氧刺激下体外形成的管网。DRP1沉默可恢复缺氧抑制的线粒体Ca(2+)。此外，特异性线粒体Ca(2+)单向转运体抑制剂Ru360可逆转DRP1促进的肺血管生成。另外，DRP1以线粒体Ca(2+)依赖的方式促进PAECs的增殖和迁移。此外，DRP1降低线粒体膜电位、减少DNA片段化并抑制caspase-3激活，而Ru360均可加剧这些变化。因此，这些结果表明线粒体裂变机制通过内皮细胞中线粒体Ca(2+)依赖的途径促进迁移、促进增殖并防止凋亡，从而导致肺血管生成。
