Department of Otolaryngology, The Second Affiliated Hospital of Fujian Medical University.
Int Heart J. 2024;65(6):1144-1152. doi: 10.1536/ihj.24-338.
Obstructive sleep apnea (OSA) is characterized by repetitive pharyngeal collapses during sleep, which leads to intermittent hypoxia, a risk factor of OSA-related cardiovascular morbidity.In this work, exosome isolation and identification with ultracentrifugation, transmission electron microscopy, nanoparticle tracking analysis, and Western blot assay were carried out. H9C2 cells were subjected to chronic intermittent hypoxia (CIH) treatment, which was followed by bone marrow mesenchymal stem cell (BMSC) -derived exosome treatment. Through reverse transcription-quantitative polymerase chain reaction (RT-qPCR), the expression of miR-744-5p was determined. Using corresponding commercial kits, the levels of oxidative stress indicators and inflammatory factors were measured. The potential target genes of miR-744-5p were predicted using four publicly target-predicting databases. To verify the interaction between miR-744-5p and NFIX, RNA pulldown and luciferase reporter assays were conducted.Significant upregulated expression of miR-744-5p in BMSC-derived exosomes was observed. The exosomes derived from miR-744-5p-overexpressing BMSCs (miR-744-5p mimics/Exo) promoted cell viability and reduced excessive inflammation and oxidative stress. Additionally, the intermolecular interaction between miR-744-5p and NFIX was determined. The exosomes derived from BMSCs cotransfecting with NFIX overexpression plasmid and miR-744-5p mimics reversed the miR-744-5p mimics/Exo-induced inhibitory effects on CIH-caused cardiomyocyte injury.BMSC-derived exosomal miR-744-5p suppressed OSA-induced cardiomyocyte damage by targeting NFIX.
阻塞性睡眠呼吸暂停（OSA）的特征是睡眠期间咽腔反复塌陷，导致间歇性缺氧，这是 OSA 相关心血管发病率的一个危险因素。在这项工作中，通过超速离心、透射电子显微镜、纳米颗粒跟踪分析和 Western blot 检测进行了外泌体分离和鉴定。将 H9C2 细胞进行慢性间歇性缺氧（CIH）处理，随后进行骨髓间充质干细胞（BMSC）衍生的外泌体处理。通过逆转录定量聚合酶链反应（RT-qPCR）测定 miR-744-5p 的表达。使用相应的商业试剂盒测定氧化应激指标和炎症因子的水平。使用四个公共靶标预测数据库预测 miR-744-5p 的潜在靶基因。为了验证 miR-744-5p 与 NFIX 之间的相互作用，进行了 RNA 下拉和荧光素酶报告基因检测。观察到 BMSC 衍生的外泌体中 miR-744-5p 的表达显著上调。来自 miR-744-5p 过表达 BMSC 的外泌体（miR-744-5p 模拟物/Exo）促进了细胞活力，减少了过度的炎症和氧化应激。此外，还确定了 miR-744-5p 和 NFIX 之间的分子间相互作用。共转染 NFIX 过表达质粒和 miR-744-5p 模拟物的 BMSC 衍生的外泌体逆转了 miR-744-5p 模拟物/Exo 诱导的对 CIH 引起的心肌细胞损伤的抑制作用。BMSC 衍生的外泌体 miR-744-5p 通过靶向 NFIX 抑制 OSA 诱导的心肌细胞损伤。
