Department of International Medical Health Care Center, Zhengzhou Yihe Hospital Affiliated to Henan University, Zhengzhou, China.
Eur Rev Med Pharmacol Sci. 2017 Jun;21(11):2734-2742.
Various human aging-related diseases start with vascular aging, in which the aging of vascular endothelium is the first step to cause a structural and functional deficit of vascular endothelium, leading to vascular disorders. MicroRNA (miR) participates in various processes of body development and pathological processes via mediating cell proliferation, differentiation, and apoptosis. A previous study showed the correlation between cardiovascular disease and miR-92a, whose role and mechanism in vascular endothelial aging has not been reported.
In vitro, cultured human umbilical vein endothelial cells (HUVECs) were prepared for the vascular endothelial aging model by using 10-6 mM angiotensin II. MiR-92a expression was examined. After transfecting with the miR-92a inhibitor, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-tetrazolium bromide (MTT) assay was employed to describe cell proliferation, and the Caspase 3 activity assay kit was used to evaluate apoptosis activity. Myeloid peroxidase (MPO) and superoxidase (SOD) activity, plus reactive oxygen species (ROS) content were measured. Nrf2, KEAP1 and ARE mRNA expressions were measured by real-time PCR. Nuclear factor erythroid 2 p45 related factor 2 (Nrf2) protein level, inflammatory factors tumor necrosis factor α (TNF-α) and interleukin-2 (IL-2) were tested by western blot or enzyme-linked immunosorbent assay (ELISA).
In model group, miR-92a expression was elevated significantly compared to the control group (p < 0 .05). MiR-92a inhibitor transfection facilitated cell proliferation, decreased Caspase 3 activity, ROS or MPO, expressions of TNF-α, IL-2 and KEAP1, and enhanced SOD level and Nrf2, ARE expressions significantly compared to the model group (p < 0.05).
In aged vascular endothelium, miR-92a was up-regulated. Through inhibiting miR-92a expression and regulating Nrf2-KEAP1-ARE signal pathway, the oxidative stress reaction or inflammation can be suppressed, thus inhibiting endothelial apoptosis and facilitating cell proliferation.
各种与人类衰老相关的疾病都始于血管衰老，其中血管内皮的衰老，是导致血管内皮结构和功能缺陷的第一步，从而导致血管紊乱。微小 RNA（miR）通过调节细胞增殖、分化和凋亡，参与了机体发育和病理过程的各个过程。先前的研究表明心血管疾病与 miR-92a 之间存在相关性，但其在血管内皮衰老中的作用和机制尚未报道。
在体外，通过使用 10-6 mM 血管紧张素 II 制备人脐静脉内皮细胞（HUVEC）的血管内皮衰老模型。检测 miR-92a 的表达。转染 miR-92a 抑制剂后，通过 3-(4,5-二甲基-2-噻唑基)-2,5-二苯基四氮唑溴盐（MTT）检测细胞增殖，Caspase 3 活性检测试剂盒评估细胞凋亡活性。测量髓过氧化物酶（MPO）和超氧化物歧化酶（SOD）活性以及活性氧（ROS）含量。通过实时 PCR 测量核因子红细胞 2 相关因子 2（Nrf2）、Kelch 样环氧氯丙烷相关蛋白 1（KEAP1）和抗氧化反应元件（ARE）mRNA 的表达。通过 Western blot 或酶联免疫吸附试验（ELISA）检测 Nrf2 蛋白水平、肿瘤坏死因子-α（TNF-α）和白细胞介素-2（IL-2）等炎症因子。
与对照组相比，模型组 miR-92a 的表达显著升高（p < 0.05）。与模型组相比，miR-92a 抑制剂转染后细胞增殖显著增加，Caspase 3 活性、ROS 或 MPO、TNF-α、IL-2 和 KEAP1 表达降低，SOD 水平和 Nrf2、ARE 表达增强（p < 0.05）。
在衰老的血管内皮中，miR-92a 上调。通过抑制 miR-92a 表达并调节 Nrf2-KEAP1-ARE 信号通路，抑制氧化应激反应或炎症反应，抑制内皮细胞凋亡，促进细胞增殖。
