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 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.

Keywords: Atrial fibrillation; Atrial fibrillation-associated ischemic stroke; Exosomes; miRNA-seq.

Fig. 1

TEM results. TEM results show the size and morphology of the exosomes.

Fig. 2

NTA results. NTA results show the size distribution and particle concentration of the exosomes.

Fig. 3

Western blot results. Western blot results confirmed the expression of the exosomal marker protein CD81 and Calnexin in the exosomes and control.

Fig. 4

qRT-PCR results. The expression of exosomal miR-641 and miR-30e-5p was increased significantly in the AF-IS group (n = 3) compared to the AF group (n = 3). *p < 0.05.