Circulating microRNAs as potential novel biomarkers in cardiovascular diseases: Emerging role, biogenesis, current knowledge, therapeutics and the road ahead

Cardiovascular diseases (CVD) are the leading cause of morbidity and mortality worldwide. Although considerable progress has been made in the diagnosis, treatment, and prognosis of CVD, there still remains a critical need for novel diagnostic biomarkers and new therapeutic interventions to reduce the incidence of diseases. Recently, there has been increasing evidence that circulating MicroRNAs (miRNAs), which are endogenous, stable, single-stranded, short, noncoding RNAs (ncRNAs), can be used as diagnostic biomarkers. miRNAs are small ncRNA having approximately 21-25 nucleotides in length, and they mainly act as transcriptional regulators of gene expression in diverse biological processes such as cellular proliferation, differentiation, and tumorigenesis and death. miRNAs regulate in several cardiovascular pathologies, not only limited to hypertrophy, heart failure, arrhythmias, hypertension, myocardial infarction, dyslipidemias, and congenital heart diseases but are also present and circulate in various body fluids such as blood, pericardial fluid, and saliva and act as potential novel biomarkers in various cardiovascular pathologies. Furthermore, miRNAs represent potential novel therapeutic targets for several of above-mentioned CVD. This review presents detailed information about miRNAs regarding its structure and biogenesis, functions, expression profiles in serum/plasma of living organisms, diagnostic and prognostic potential as a novel biomarker and therapeutic applications in various CVD.