Cardiovascular epigenetics: from DNA methylation to microRNAs

Epigenetic phenomena define heritable mechanisms that establish and maintain mitotically stable patterns of gene expression regulation that occur without modifying the base sequence of DNA. The major epigenetic features of mammalian cells enclose DNA methylation, post-translational histone modifications and RNA-based mechanisms including those controlled by small non-coding RNAs (miRNAs). Their impact in cardiovascular pathophysiology is now emerging as a major interface between genotype to phenotype variability with strict implications on disease development and progression, opening up to possible novel preventive strategies. Epigenetic mechanisms are potentially reversible and may be influenced by nutritional-environmental factors as well as through gene-environment interactions, all of which have an important role in complex, multifactorial diseases such as those affecting the cardiovascular system. Gene expression regulation through the interplay of DNA methylation and histone modifications is well-established, although the knowledge about the function of epigenetic signatures in cardiovascular disease is still largely unexplored. The study of epigenetic markers is, therefore, an emerging and very promising frontier of science which may help for a deeper understanding of molecular mechanisms underlying the modulation of gene expression in cardiovascular disease-linked biomolecular pathways. This review will focus on up-to-date knowledge pertaining to the role of epigenetics, from DNA methylation to miRNAs, in major cardiovascular diseases such as ischemic heart disease, hypertension, heart failure and stroke.