Li Juan, Li Peng, Zhao Yanzhuo, Ma Xiang, He Ruili, Liang Ketai, Zhang Erwei
Department of Cardiology, Huaihe Hospital of Henan University No. 8 Baobei Road, Gulou District 475000 Kaifeng Henan China
RSC Adv. 2019 Sep 9;9(48):28213-28221. doi: 10.1039/c9ra05176g. eCollection 2019 Sep 3.
MicroRNAs (miRNAs) have recently attracted increasing attention for their involvement in atherosclerosis (AS). The purpose of this study was to further explore the function and underlying mechanism of miR-135a in AS progression. The expression levels of miR-135a and lipoprotein lipase (LPL) mRNA were detected by qRT-PCR, and LPL protein expression was measured by western blotting. The levels of blood lipids and inflammatory cytokines, and LPL activity were assessed using corresponding Assay Kits, and an HPLC assay was used to determine the levels of free cholesterol (FC), total cholesterol (TC) and cholesterol ester (CE). A Dil-oxLDL binding assay was performed to evaluate the ability of cholesterol uptake. The direct interaction between miR-135a and LPL was confirmed by a dual-luciferase reporter assay and RNA immunoprecipitation assay. Our data indicated that miR-135a was downregulated in serum samples of AS patients and mice. Upregulation of miR-135a alleviated lipid metabolic disorders and inflammation in AS mice. Moreover, miR-135a negatively regulated lipid accumulation and inflammation in ox-LDL-treated THP-1 macrophages. Mechanistically, miR-135a directly targeted LPL and repressed LPL expression. LPL mediated the regulatory effect of miR-135a on lipid accumulation and inflammation in ox-LDL-treated THP-1 macrophages. In conclusion, our study indicated that miR-135a upregulation ameliorated lipid accumulation and inflammation at least partly by targeting LPL in THP-1 macrophages, highlighting miR-135a as a potential antiatherogenic agent.
微小RNA（miRNA）因其参与动脉粥样硬化（AS）过程，近来受到越来越多的关注。本研究的目的是进一步探讨miR-135a在AS进展中的作用及其潜在机制。采用qRT-PCR检测miR-135a和脂蛋白脂肪酶（LPL）mRNA的表达水平，用蛋白质免疫印迹法检测LPL蛋白表达。使用相应的检测试剂盒评估血脂和炎性细胞因子水平以及LPL活性，并用高效液相色谱法检测游离胆固醇（FC）、总胆固醇（TC）和胆固醇酯（CE）水平。进行Dil-oxLDL结合试验以评估胆固醇摄取能力。通过双荧光素酶报告基因试验和RNA免疫沉淀试验证实miR-135a与LPL之间存在直接相互作用。我们的数据表明，AS患者和小鼠血清样本中miR-135a表达下调。上调miR-135a可减轻AS小鼠的脂质代谢紊乱和炎症。此外，miR-135a对氧化型低密度脂蛋白（ox-LDL）处理的THP-1巨噬细胞中的脂质积累和炎症具有负调控作用。机制上，miR-135a直接靶向LPL并抑制LPL表达。LPL介导miR-135a对ox-LDL处理的THP-1巨噬细胞中脂质积累和炎症的调节作用。总之，我们的研究表明，上调miR-135a至少部分通过靶向THP-1巨噬细胞中的LPL改善脂质积累和炎症，突出了miR-135a作为一种潜在抗动脉粥样硬化药物的作用。
