We studied hearts isolated from canines with chronic HF exhibiting increased left ventricular (LV) dimensions and decreased LV contractility. qRT-PCR revealed that the levels of miR-1 and miR-133, the most abundant muscle-specific miRNAs, were significantly increased in HF myocytes compared with controls (2- and 1.6-fold, respectively).
The decreased expression of muscle-specific microRNA-1 (miR-1) has been found in many cardiovascular diseases and is considered to contribute to heart failure (HF).
MicroRNAs (miRNAs) play a key role in the development of heart failure, and recent studies have shown that the muscle-specific miR-1 is a key regulator of cardiac hypertrophy.
The miR-21 expression is more valuable than the miR-1 expression in predicting cardiovascular events of acute HF and the combined analysis of miR-21 expression, galectin-3, and NT-proBNP can increase the predictive value of miR-21 expression.
Myocardial biopsy specimens taken from Chinese patients presenting with recent heart failure were compared with a group of patients without heart failure undergoing routine cardiac surgery (n=34). miRNAs (miR-1, -21, -23, -29, -30, -130, -133, -195, -199, -208, and -320) and corresponding mRNA expression were measured by real-time quantitative-PCR method. miR-1, -21, -23, -29, -130, -195 and -199 were significantly up-regulated in the heart failure group when compared to those without heart failure (all p<0.01).
Based on previous findings, the expression of 13 different microRNAs involving heart failure and hypertrophy (miR-1-3p, miR-10b, miR-21, miR-23a, miR-27a, miR-29a, miR-133a-3p, miR-142-3p, miR-155, miR-199a-3p, miR-199a-5p, miR-214, miR-497) was measured.
Both iptakalim and natakalim significantly upregulated the expression of miR-1-3p, suggesting that this miR is closely associated with the therapeutic effects against chronic heart failure.
Cardio-enriched miRNAs (miR-1, miR-208b and miR-499-5p) were measured using real time PCR in plasma samples from 424 patients with suspected ACS treated in a coronary care unit. miRNAs were assessed for discrimination of a clinical diagnosis of myocardial infarction and for association with 30-day mortality and diagnosis of heart failure.
It has been shown that miR-1 can reverse cardiac hypertrophy during the compensatory phase of HF development, but it is unknown whether miR-1 can still reverse cardiac dysfunction and improve cardiac remodeling after HF progresses to the decompensation stage.
These findings demonstrate the importance of miR-1 in cardiac function and in the pathogenesis of heart failure via Sorcin-dependent calcium homeostasis.