线粒体ALDH2通过调控自噬对缺氧性肺动脉高压的保护机制研究

目的：探讨激活线粒体乙醛脱氢酶2(ALDH2)可以降低因缺氧所引起的平滑肌细胞自噬，并降低肺动脉平滑肌细胞(PASMCs)的增殖，分析ALDH2对缺氧性肺动脉高压平滑肌增殖的调控关系。方法：将SPF级雄性SD大鼠分4组：正常对照组(N组)、常氧+ALDH2特异性激动剂Alda-1组(N+Alda-1组)、缺氧组(H组)、缺氧+Alda-1组(H+Alda-1组),将PASMCs分为6组：常氧组(N组)、常氧+Alda-1组(NA组)、缺氧组(H组)、缺氧+Alda-1组(HA组)、缺氧+ALDH2抑制剂Daidzin组(HD组)、缺氧+Alda-1+Daidzin组(HAD组)。HE染色观察各组动物肺组织中肺动脉病理变化；免疫荧光鉴定肺动脉平滑肌细胞；CCK-8测定各组细胞增殖能力；Annexin V-FITC/PI双染测定细胞凋亡水平；Western blotting检测各组ALDH2、p62、Beclin1、LC3B等蛋白的表达。结果：与N组相比，H组肺小动脉管壁增厚，管腔变窄；与HC组相比，H+Alda-1组的肺小动脉管壁厚度减轻，管腔狭窄程度有所改善；与N组相比，H组的ALDH...

Protective mechanism of mitochondrial ALDH2 on hypoxic pulmonary hypertension by regulating autophagy

ObjectiveTo investigate the effect of activating mitochondrial aldehyde dehydrogenase on the autophagy of smooth muscle cells induced by hypoxia and the proliferation of pulmonary artery smooth muscle cells, and to analyze the regulation of mitochondrial aldehyde dehydrogenase on the proliferation of smooth muscle cells induced by hypoxia pulmonary arterial hypertension.MethodsMale SD rats of SPF grade were divided into four groups: normal control group (N group), normoxia+ALDH2 agonist Alda-1 group (N+Alda-1 group), model group (H group), and hypoxia+Alda-1 group (H+Alda-1 group).PASMCs was divided into six groups: normoxia group (N group), normoxia+Alda-1 group (NA group), hypoxia group (H group), hypoxia+Alda-1 group (HA group), hypoxia+ALDH2 inhibitor Daidzin group (HD group), and hypoxia+Alda-1+Daidzin group (HAD group).HE staining was performed to observe the pathological changes of pulmonary artery in the lung tissue of each group, immunofluorescence was used to identify pulmonary artery smooth muscle cells, CCK-8 was applied to determine the cell viability and proliferation of each group, Annexin V-FITC/PI double staining was employed to detect apoptosis level, and Western blotting was used to analyze the protein expression of ALDH2, p62, Beclin1 and LC3B.ResultsCompared with the N group, the walls of pulmonary arterioles was thickened and the lumen was narrowed in the H group.Compared with the H group, the thickness of pulmonary small artery wall was reduced, and the degree of stenosis was improved in the H+Alda-1 group.Compared with the group N, the expression of ALDH2 decreased (P < 0.05), the expression of autophagy-related proteins p62, Beclin1 and LC3B increased significantly (P < 0.01), and the cell proliferation increased significantly in the group H (P < 0.01).Compared with the group H, the expression of ALDH2 was significantly increased (P < 0.01), the expression of autophagy-related proteins p62, Beclin1 and LC3B obviously decreased (P < 0.01), and the cell proliferation was markedly inhibited in the HA group (P < 0.01).ConclusionsMitochondrial ALDH2 has a significant inhibitory effect on the proliferation of hypoxia-induced PASMCs, and the mechanism may be related to the autophagy regulation of ALDH2 on cells.