Diagnostic value of microRNA-27 and -339 in heart transplant recipients with myocardial fibrosis

Abstract

Myocardial fibrosis plays a key role in the pathogenesis of heart failure. A family of small non-coding signaling molecules, microRNAs (miRNAs), has been identified as promising profibrogenic biomarkers capable of signaling a possible risk of adverse events after heart transplantation.Objective: to identify and evaluate the diagnostic significance of miRNAs, as well as comprehensive miRNA-based tests in heart recipients with graft myocardial fibrosis.Materials and Methods. The study included 83 heart recipients aged 16 to 64 (48.4 ± 13.1) years. The expression levels of five microRNAs (miR-27, -101, -142, -339, -424) in venous blood plasma were measured by quantitative real-time polymerase chain reaction; galectin-3 serum levels were determined by enzyme immunoassay.Results. Morphological signs of graft myocardial fibrosis were verified in 48 recipients. The miR-27 and miR-339 expression levels were significantly higher in heart recipients with myocardial fibrosis than in those without myocardial fibrosis (p = 0.018 and p = 0.043, respectively). Diagnostically significant threshold levels of miR-27 and miR-339 for detection of myocardial fibrosis in heart transplant recipients were determined (–4.33 and –5.24 units, respectively). The relative risk of detecting graft myocardial fibrosis in recipients with miR-27 expression value above the threshold level was RR = 1.5 ± 0.157 [95% CI 1.104-2.039], p = 0.009; for miR-339, RR = 1.31 ± 0.130 [95% CI 1.018-1.692], p = 0.036. When miR-27 expression levels and galectin-3 serum levels simultaneously exceeded their estimated thresholds, the risk of transplanted heart myocardial fibrosis increased to RR = 2.7 ± 0.456 [95% CI 1.090-6.524], p = 0.032; when miR-339 and galectin-3 simultaneously exceeded threshold values, the risk was RR = 2.0 ± 0.316 [95% CI 1.076-3.717], p = 0.028).Conclusion. The miR-27 and miR-339 expression levels are associated with the presence of fibrotic changes in the graft myocardium. The combination of molecular-genetic and proteomic biomarkers in one test improves the diagnostic characteristics of these expressions with respect to post-transplant complications in heart recipients.