Abstract 14102: Exercise Training Restores Circulating microRNAs to Nonpathological Levels in Patients With Heart Failure

IntroductionA greater appreciation of the benefits of exercise-based cardiac rehabilitation (CR) in patients with heart failure (HF) has emerged over the last decade. However, the molecular mechanisms underlying its beneficial effects remain elusive. Micro RNAs (miRNAs) are short noncoding RNAs consisting of 18-25 nucleotides regulating the expression of target genes post-transcriptionally, and the impact of CR on the circulating miRNA expression profiles is still unknown.HypothesisIf miRNAs respond to changes following CR, then serum profiling of these miRNAs may reveal cardio-protective mechanisms of CR in HF.MethodsTwenty patients with systolic HF performing CR and 3 healthy controls were enrolled in the present study. We randomly selected 3 patients with HF (60.0 ± 12.2 years old; mean ± SD) and 3 controls (58.7 ± 0.58 years old) to perform the genome-wide expression profiling for circulating miRNAs using microarray, and the differences of circulating miRNA expression profiles between patients with HF before and after CR and heathy controls were evaluated.ResultsCirculating 90 miRNAs expressions in patients with HF before CR were significantly decreased compared with healthy controls, and circulating 77 miRNAs expressions in patients with HF before CR were significantly increased compared with healthy controls. Exercise training in patients with HF normalized the expressions of 5 of 90 miRNAs (miR-7151-3p, miR-3945, miR-30c-1-3p, miR-196b-3p, miR-1290) and 3 of 77 miRNAs (miR-125b-1-3p, miR-24-3p, miR-3661), respectively (p < 0.05). Serum levels of NT-proBNP in patients with HF was decreased from 2489 ± 2014 pg/ml before CR to 1023 ± 926 pg/ml after CR.ConclusionsThese results suggest that exercise training restores a set of circulating miRNAs expression levels in patients with HF. Our data uncover the potential contribution of miRNAs to HF and highlight the beneficial effects of exercise training by regulating miRNAs through multiple effects on gene expression.