MicroRNA-486-5p functions as a diagnostic marker for carotid artery stenosis and prevents endothelial dysfunction through inhibiting inflammation and oxidative stress

Carotid artery stenosis (CAS) can cause ischemic stroke, and clinical intervention for CAS is critical clinically. The purpose of this study was to explore the expression changes of microRNA-486-5p in the serum of patients with CAS and its possible mechanism. Ninety-one cases with asymptomatic CAS were recruited, and serum levels of miR-486-5p were measured using RT-qPCR. The diagnostic ability was evaluated by drawing the receiver operating characteristic (ROC) curve. Human aortic endothelial cells (HAECs) were treated with oxidized low-density lipoprotein (oxLDL) to establish cell model, and cell proliferation and apoptosis were tested. The markers of cell inflammation and oxidative stress were detected via ELISA. The target gene was analyzed using bioinformatics analysis combined with luciferase reporting assay. CAS cases exhibited significantly low serum miR-486-5p levels in comparison with the control group and can identify asymptomatic CAS. Serum miR-486-5p manifested a negative correlation with the degree of carotid stenosis. Underexpression of miR-486-5p was also detected in ox-LDL treated HAECs. OxLDL treatment contributes to inflammatory response and oxidative stress of HAECs; however, these adverse impacts caused by ox-LDL were reversed by miR-486-5p upregulation. NFAT5 was confirmed to be the target gene of miR-486-5p in HAECs. MiR-486-5p serves as a promising biomarker for the early identification of CAS. Overexpression of miR-486-5p can prevent endothelial dysfunction, and the mechanism might be related to anti-inflammation and anti-oxidation via targeting NFAT5.

颈动脉狭窄（Carotid artery stenosis, CAS）可引发缺血性脑卒中，其临床干预在临床诊疗中至关重要。本研究旨在探讨microRNA-486-5p（miR-486-5p）在颈动脉狭窄患者血清中的表达变化及其潜在作用机制。本研究共招募91例无症状颈动脉狭窄患者，采用逆转录实时定量聚合酶链反应（RT-qPCR）检测受试者血清中miR-486-5p的表达水平；通过绘制受试者工作特征（receiver operating characteristic, ROC）曲线评估其诊断效能。采用氧化型低密度脂蛋白（oxidized low-density lipoprotein, oxLDL）处理人主动脉内皮细胞（human aortic endothelial cells, HAECs）构建细胞损伤模型，检测细胞增殖与凋亡水平；通过酶联免疫吸附试验（ELISA）检测细胞炎症与氧化应激相关标志物。结合生物信息学分析与双荧光素酶报告基因实验筛选并验证miR-486-5p的靶基因。与对照组相比，颈动脉狭窄患者血清miR-486-5p水平显著降低，且该指标可有效识别无症状颈动脉狭窄；血清miR-486-5p水平与颈动脉狭窄程度呈负相关。在oxLDL处理的HAECs中，同样检测到miR-486-5p的低表达。oxLDL处理可诱导HAECs产生炎症反应与氧化应激，但miR-486-5p过表达可逆转oxLDL引发的上述不良效应。经验证，NFAT5是HAECs中miR-486-5p的靶基因。综上，miR-486-5p可作为早期识别颈动脉狭窄的潜在生物标志物；miR-486-5p过表达可改善内皮功能障碍，其机制可能通过靶向NFAT5发挥抗炎与抗氧化作用。