过表达miRNA-29a对野百合碱诱导的大鼠肺动脉高压的作用

目的:检测微小RNA(miRNA)-29a在野百合碱诱导的肺动脉高压大鼠肺动脉血管壁组织中的表达,研究过表达miRNA-29a对肺动脉高压大鼠的影响,并探讨其初步机制。方法:在野百合碱诱导的肺动脉高压大鼠模型上,用实时荧光定量PCR测定肺组织miRNA-29a的表达水平;尾静脉注射miRNA-29a-mimic后,记录大鼠肺动脉压和体循环动脉压,苏木素-伊红染色观察肺动脉组织的形态,Western blot检测肺动脉组织中p-Akt与peNOS的蛋白水平。结果:野百合碱诱导的肺动脉高压大鼠肺动脉血管壁组织中miRNA-29a呈低表达;过表达miRNA-29a后,大鼠肺动脉压明显下降,体循环血压无显著变化,肺动脉中膜增厚程度显著减弱,肺血管重构现象不明显,p-Akt与p-eNOS的蛋白水平上调。结论:过表达miRNA-29a对野百合碱诱导的大鼠肺动脉高压具有改善作用,可能与激活PI3k/Akt-eNOS信号通路有关。

Effects of miRNA-29a on monocrotaline-induced pulmonary hypertension in rats

AIM: To detect the expression of microRNA (miRNA)-29a in pulmonary arteries of monocrotaline (MCT)-induced pulmonary hypertensive rats, and to investigate the effects of miRNA-29a on pulmonary hypertension. METHODS: MCT-induced pulmonary hypertensive model was established in Wistar rats. The expression of miRNA-29a in the lung tissue was determined by qPCR. miRNA-29a was overexpressed in the pulmonary hypertension rats by tail vein injection of miRNA-29a-mimic. Pulmonary artery pressure (PAP) and systemic arterial pressure (SAP) were measured. The morphological changes of the pulmonary arteries were observed by HE staining. The protein levels of p-Akt and p-eNOS were detected by Western blot.RESULTS: The mRNA expression of miRNA-29a was significantly decreased in the pulmonary arteries of MCT-induced pulmonary hypertensive rats. Furthermore, after overexpression of miRNA-29a, PAP was remarkably reduced, while SAP remained unchanged. In addition, the increased thickness of tunica media, the remodeling of pulmonary arteries and the decreased protein levels of p-Akt and p-eNOS in the pulmonary hypertensive rats were dramati-cally changed after miRNA-29a overexpression.CONCLUSION: Overexpression of miRNA-29a ameliorates pulmonary hypertension in rats. These effects may be associated with the activation of PI3K/Akt-eNOS signaling pathway.