PIWI-Interacting RNAs in Cardiovascular Disease: From Epigenetic Regulators to Clinical Biomarkers and Therapeutic Targets.

PIWI-interacting RNAs (piRNAs) are a class of non-coding RNAs approximately 24-32 nucleotides (nt) in length. They are well known for silencing transposons and maintaining genomic integrity during germ cell development. Recent studies have detected specific piRNAs in cardiovascular-relevant tissues, including myocardial tissue, circulating samples, and distinct cardiac cell populations, as well as in various disease settings. However, the biogenesis and functions of somatic piRNA/P-element-induced wimpy testis proteins (PIWI) signaling in mammalian cardiovascular tissues remain incompletely understood. The biological functions of piRNAs in cardiac physiology and the pathogenesis of various diseases are still largely unexplored. In this review, we summarize piRNA expression patterns, underlying mechanisms, and potential clinical significance in cardiovascular diseases, providing insights that may facilitate the development of targeted molecular therapies.