Relaxin-2 as a Potential Biomarker in Cardiovascular Diseases

The pleiotropic hormone relaxin-2 plays a pivotal role in the physiology and pathology of the cardiovascular system. Relaxin-2 exerts relevant regulatory functions in cardiovascular tissues through the specific receptor relaxin family peptide receptor 1 (RXFP1) in the regulation of cardiac metabolism; the induction of vasodilatation; the reversion of fibrosis and hypertrophy; the reduction of inflammation, oxidative stress, and apoptosis; and the stimulation of angiogenesis, with inotropic and chronotropic effects as well. Recent preclinical and clinical outcomes have encouraged the potential use of relaxin-2 (or its recombinant form, known as serelaxin) as a therapeutic strategy during cardiac injury and/or in patients suffering from different cardiovascular disarrangements, especially heart failure. Furthermore, relaxin-2 has been proposed as a promising biomarker of cardiovascular health and disease. In this review, we emphasize the relevance of the endogenous hormone relaxin-2 as a useful diagnostic biomarker in different backgrounds of cardiovascular pathology, such as heart failure, atrial fibrillation, myocardial infarction, ischemic heart disease, aortic valve disease, hypertension, and atherosclerosis, which could be relevant in daily clinical practice and could contribute to comprehending the specific role of relaxin-2 in cardiovascular diseases.