Lin Hui, Pan Sunlei, Meng Liping, Zhou Changzuan, Jiang Chengjian, Ji Zheng, Chi Jufang, Guo Hangyuan
The First Clinical Medical College, Wenzhou Medical University, Wenzhou 325000, Zhejiang, China.
Department of Cardiology, Shaoxing People's Hospital, Shaoxing Hospital of Zhejiang University, Shaoxing 312000, Zhejiang, China.
Biochem Biophys Res Commun. 2017 Jul 1;488(3):453-460. doi: 10.1016/j.bbrc.2017.05.035. Epub 2017 May 5.
Angiotensin II (Ang II)-induced damage to endothelial cells (ECs) plays a crucial role in the pathogenesis of atherosclerosis. This study aimed to investigate the role of microRNA-384 (miR-384) in endothelial cell apoptosis.
The expression of five various miRNAs in Ang II-treated human umbilical vein endothelial cells (HUVECs) were detected by qPCR. The Ang II-induced apoptosis of HUVECs was determined by flow cytometry, TUNEL staining and western blot. Endoplasmic reticulum (ER) stress markers were detected by western blot analysis. The target gene of miR-384 was determined by bioinformatics analyses. qPCR, western blotting and immunofluorescence were performed to determine the expression level of homocysteine inducible ER protein with ubiquitin like domain 1 (Herpud1).
miR-384 expression level was significantly decreased in Ang II-treated HUVECs. Ang II-induced HUVEC apoptosis was accompanied by the occurrence of ER stress. A decreased rate of HUVEC apoptosis and a decreased rate of ER stress were observed following restoration of miR-384 expression. Herpud1 expression level was increased in HUVECs treated with Ang II, and miR-384 mimics effectively inhibited Herpud1 expression. Mechanistically, miR-384 directly targets the 3'-untranslated region of Herpud1. Furthermore, effects of miR-384 on HUVECs apoptosis and ER stress were at least partly reversed by knockdown of Herpud1 expression.
The results of the present study collectively indicated that miR-384 expression level was downregulated in Ang II-treated HUVECs and miR-384 overexpression protected HUVECs against Ang II-induced apoptosis by negatively regulating Herpud1. These findings point towards new strategies by which apoptosis of ECs can be suppressed.
血管紧张素II（Ang II）诱导的内皮细胞（ECs）损伤在动脉粥样硬化发病机制中起关键作用。本研究旨在探讨微小RNA-384（miR-384）在内皮细胞凋亡中的作用。
通过qPCR检测Ang II处理的人脐静脉内皮细胞（HUVECs）中5种不同微小RNA的表达。通过流式细胞术、TUNEL染色和蛋白质印迹法测定Ang II诱导的HUVECs凋亡。通过蛋白质印迹分析检测内质网（ER）应激标志物。通过生物信息学分析确定miR-384的靶基因。进行qPCR、蛋白质印迹和免疫荧光以确定含泛素样结构域1的同型半胱氨酸诱导型ER蛋白（Herpud1）的表达水平。
Ang II处理的HUVECs中miR-384表达水平显著降低。Ang II诱导的HUVEC凋亡伴随着ER应激的发生。恢复miR-384表达后，观察到HUVEC凋亡率降低和ER应激率降低。Ang II处理的HUVECs中Herpud1表达水平升高，miR-384模拟物有效抑制Herpud1表达。机制上，miR-384直接靶向Herpud1的3'-非翻译区。此外，Herpud1表达敲低至少部分逆转了miR-384对HUVECs凋亡和ER应激的影响。
本研究结果共同表明，Ang II处理的HUVECs中miR-384表达水平下调，miR-384过表达通过负调控Herpud1保护HUVECs免受Ang II诱导的凋亡。这些发现为抑制ECs凋亡的新策略指明了方向。
