Supplementary Material for: Differentiation of Atrial Fibrillation and Atrial Fibrillation-Associated Ischemic Stroke Based on Serum Exosome miRNA-seq

Abstract Introduction: Atrial fibrillation (AF) is the most common cardiac arrhythmia in the general population, and stroke is the most severe complication of AF. Exosomal miRNAs have been reported to be candidates as biomarkers for cardiovascular diseases, including AF and stroke. This study aimed to identify differentially expressed miRNAs (DEMs) in serum exosomes of AF and AF-associated ischemic stroke (AF-IS) patients and evaluate their potential in distinguishing AF and AF-IS patients. Methods: Serum exosomes were isolated from 8 healthy individuals with sinus rhythm (SR controls), 8 AF patients, and 8 AF-IS patients. miRNA-seq was performed to identify DEMs, and qRT-PCR analysis was performed to confirm the sequencing results. A support vector machine (SVM) model was developed using Python to distinguish AF and AF-IS patients. Results: 68 and 86 DEMs were identified in serum exosomes of AF patients compared to AF-IS patients and SR controls, respectively. Levels of miR-641 and miR-30e-5p were found significantly higher in AF-IS patients. The SVM model achieved an accuracy of 100%, with an area under curve (AUC) of 1. Conclusions: The results indicated that miRNA expression profiles of serum exosomes in AF patients were distinct from those in AF-IS patients, and based on the distinction, AF and AF-IS patients can be distinguished.

摘要 引言：心房颤动（Atrial fibrillation, AF）是普通人群中最常见的心律失常类型，而脑卒中是房颤最为严重的并发症。已有研究表明，外泌体微小RNA（exosomal miRNAs）可作为包括房颤和脑卒中在内的心血管疾病的生物标志物候选物。本研究旨在鉴定房颤患者及房颤相关性缺血性脑卒中（AF-associated ischemic stroke, AF-IS）患者血清外泌体中的差异表达miRNA（DEMs），并评估其用于区分房颤与房颤相关性缺血性脑卒中患者的潜力。方法：本研究从8名窦性心律（sinus rhythm, SR）健康个体（SR对照组）、8名房颤患者以及8名房颤相关性缺血性脑卒中患者中分离血清外泌体。通过miRNA测序（miRNA-seq）筛选差异表达miRNA，并采用实时定量聚合酶链反应（qRT-PCR）对测序结果进行验证。使用Python构建支持向量机（support vector machine, SVM）模型，以区分房颤与房颤相关性缺血性脑卒中患者。结果：与房颤相关性缺血性脑卒中患者及窦性心律健康对照组相比，房颤患者血清外泌体中分别鉴定出68个和86个差异表达miRNA。相较于其他组别，房颤相关性缺血性脑卒中患者血清中miR-641与miR-30e-5p的表达水平显著升高。所构建的支持向量机模型准确率达100%，曲线下面积（AUC）为1。结论：本研究结果显示，房颤患者血清外泌体的miRNA表达谱与房颤相关性缺血性脑卒中患者存在显著差异，基于该表达差异可有效区分房颤与房颤相关性缺血性脑卒中患者。