Department of Molecular Biology, School of Intelligent Medicine and Biotechnology, Guilin Medical University, Guilin, China.
Department of Biochemistry and Molecular Biology, Hengyang Medicine School, University of South China, Hengyang, China.
J Biochem Mol Toxicol. 2024 Jan;38(1):e23598. doi: 10.1002/jbt.23598. Epub 2023 Dec 4.
Endothelial cell apoptosis driven by inflammation (TNF-α) plays a critical role in the pathogenesis of atherosclerosis, but the exact molecular mechanisms are not clearly elucidated. MicroRNA (miR)-29 families (a/b/c) take important roles in pathophysiological processes of atherosclerosis, also the underlying mechanisms have not been fully clarified. The aims are to explore whether or not miR-29 families mediate the apoptotic effects of TNF-α on endothelial cells and uncover the underlying molecular mechanisms. In this study, MTT assay and flow cytometer analysis were employed respectively to determine the proliferation and apoptosis of human umbilical vascular endothelial cells (HUVECs) under TNF-α exposure. Real-time quantitative PCR and western blot were performed to detect the levels of target RNAs and proteins/their phosphorylation in HUVECs. TNF-α could inhibit HUVEC proliferation and induce HUVEC apoptosis in a positive dose- and time-dependent manner, with a similar way of miR-29a upregulation, but no effects on miR-29b/c. Upregulation of miR-29a with its mimics enhanced the apoptotic effect of TNF-α on HUVECs, but downregulation of miR-29a using anti-miR-29a blocked up its apoptotic effect. MiR-29a inhibited the expression of PI3Kp85α and Bcl-2 and blocked up the signal transduction of PI3K/AKT/Bcl-2 axis to mediate the apoptotic effect of TNF-α on HUVECs. Mediating the inflammation-driven endothelial cell apoptosis is an important biology mechanism by which miR-29a promotes atherosclerosis and its complications. MiR-29a will be a potential diagnostic and therapeutic target for atherosclerotic cardiovascular diseases; it is worthwhile to further study.
炎症（TNF-α）驱动的内皮细胞凋亡在动脉粥样硬化的发病机制中起关键作用，但确切的分子机制尚不清楚。miR-29 家族（a/b/c）在动脉粥样硬化的病理生理过程中发挥重要作用，其潜在机制尚未完全阐明。本研究旨在探讨 miR-29 家族是否介导 TNF-α对内皮细胞的凋亡作用，并揭示其潜在的分子机制。本研究采用 MTT 法和流式细胞术分别检测 TNF-α作用下人脐静脉内皮细胞（HUVEC）的增殖和凋亡，实时定量 PCR 和 Western blot 检测 HUVEC 中靶 RNA 和蛋白/其磷酸化水平。TNF-α可呈剂量和时间依赖性抑制 HUVEC 增殖并诱导其凋亡，同时呈相似方式上调 miR-29a，但对 miR-29b/c 无影响。miR-29a 模拟物上调 miR-29a 增强了 TNF-α对 HUVEC 的凋亡作用，而 miR-29a 反义寡核苷酸则阻断了其凋亡作用。miR-29a 抑制 PI3Kp85α 和 Bcl-2 的表达，阻断了 PI3K/AKT/Bcl-2 信号通路的转导，从而介导 TNF-α对 HUVEC 的凋亡作用。miR-29a 介导炎症驱动的内皮细胞凋亡是 miR-29a 促进动脉粥样硬化及其并发症的重要生物学机制。miR-29a 可能成为动脉粥样硬化性心血管疾病的潜在诊断和治疗靶点，值得进一步研究。
