Circulating exosomal miR-92b-5p is a promising diagnostic biomarker of heart failure with reduced ejection fraction patients hospitalized for acute heart failure

Tao Wu, Yichen Chen, Yantao Du, Jin Tao, Wei Li, Zhong Zhou, Zhuo Yang


Background: Circulating microRNA (miRNA) biomarkers have been extensively reported in cardiovascular diseases (CVDs). However, serum exosomal miRNA (exo-miRNA) as biomarker in patients with heart failure (HF) with reduced ejection fraction (HFrEF) remain largely unexplored. We sought to investigate the potential of three types of serum exo-miRNAs as biomarkers for diagnosis in HFrEF patients who were admitted in hospital because of acute heart failure (AHF).
Methods: A total of 28 HFrEF patients hospitalized for AHF, including de novo AHF and acute decompensated HF, and 30 volunteers as control group (CG) from 2015 to 2017 were enrolled in this study. Serum exo-miRNAs were extracted and analyzed by NaNOZS-90, electron microscopy, and western blotting. Three types of serum exo-miRNAs (exo-miR-92b-5p, -192-5p, and -320a) were assessed by quantitative real time polymerase chain reaction (qRT-PCR).
Results: The particle size was confirmed as 40–150 nm using NaNOZS-90 and transmission electron microscopy. Exosomal biomarkers CD63 and Hsp70 were readily detected. The expression level of serum exo-miRNAs were transformed into log2−delta CT in the qPCR assay. The data showed that exo-miR-92b-5p was elevated in HFrEF patients compared with controls. Moreover, exo-miR-92b-5p was inversely correlated with the left ventricular fraction shortening (LVFS) and left ventricular ejection fraction (LVEF), whereas it was positively correlated with left atrial diameter (LAD), left ventricular diastolic diameters (LVDD) and systolic diameters (LVSD). A receiver operating characteristic (ROC) curve was generated for discrimination between HFrEF patients and controls based on exo-miR-92b-5p (P<0.001, sensitivity =71.4%, specificity =83.3%).
Conclusions: Exo-miR-92b-5p levels in the serum may serve as a marker for HFrEF diagnosis.