Cardiovascular epigenetics: from DNA methylation to microRNAs.

Epigenetic phenomena are defined as heritable mechanisms that establish and maintain mitotically stable patterns of gene expression without modifying the base sequence of DNA. The major epigenetic features of mammalian cells include DNA methylation, post-translational histone modifications and RNA-based mechanisms including those controlled by small non-coding RNAs (miRNAs). The impact of epigenetic mechanisms in cardiovascular pathophysiology is now emerging as a major player in the interface between genotype to phenotype variability. This topic of research has strict implications on disease development and progression, and opens up possible novel preventive strategies in cardiovascular disease. An important aspect of epigenetic mechanisms is that they are potentially reversible and may be influenced by nutritional-environmental factors and 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, a very promising frontier of science which may aid in a deeper understanding of molecular mechanisms underlying the modulation of gene expression in the biomolecule pathways linked to cardiovascular diseases. This review focuses 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.