Diagnostic Value And Clinical Significance Of MiRNA-320c In Atrial Fibrosis In Atrial Fibrillation Patients.

Background Left atrial fibrosis is a significant manifestation of abnormal atrial tissue structure in patients with atrial fibrillation(AF).It is considered to be the basis for AF maintenance and the main reason of atrial cardiomyopathy,ACM-.Exosomal micro RNAs(miRNAs)may play an essential role in promoting the process of atrial fibrosis and facilitating the occurrence of left atrial fibrosis.MethodsIn order to identify differentially expressed miRNAs(DEmiRNAs)in the discovery phase,high-throughput sequencing of exosomal miRNAs in the coronary sinus venous blood of persistent AF patients with a mild degree of left atrial fibrosis(n = 4),severe left atrial fibrosis(n = 4),and of patients with supraventricular tachycardia(SVT)serving as the control group(n = 5),was performed.In the validation phase,quantitative real-time reverse transcription polymerase chain reaction analysis of the exosomal DEmiRNAs in severe left atrial fibrosis AF(n = 60)and SVT(n = 30)patients was carried out.The target genes were then utilized in gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses.ResultsFour exosomal DEmiRNAs from the coronary sinus were discovered via high-throughput sequencing between severe left atrial fibrosis AF and SVT patients,including miR-5106,let-7e-5p,miR-320 c,and miR-382-3p.In the validation phase,exosomal miR-320 c was down-regulated using quantitative real-time reverse transcription polymerase chain reaction analysis in severe left atrial fibrosis AF patients,but there were no significant changes in miR-5106,let-7e-5p,and miR-382-3p.The miR-320 c was predicted using the target genes in cardiac fibrosis-related pathways,such as phosphoinositide 3-kinase/protein kinase B and adenosine monophosphate-activated protein kinase signaling pathways.ConclusionsThe miR-320 c may serve as a biomarker of severe left atrial fibrosis.Furthermore,it is a potential therapeutic target in AF-induced ACM.Following studies are needed to explore the related signaling pathways.