Botanicals as epigenetic modulators for mechanisms contributing to development of metabolic syndrome.

Epigenetics refers to heritable changes in gene expression that are not attributable to changes in DNA sequence and impacts many areas of applied and basic biology including developmental biology, gene therapy, somatic cell nuclear transfer, somatic cell reprogramming, and stem cell biology. Epigenetic changes are known to contribute to aging in addition to multiple disease states. Epigenetic changes can be influenced by environmental factors that in turn can be inherited by daughter cells during cell division and can also be inherited through the germ line. Thus, it is intriguing to consider that epigenetics, in general, may play a role in human conditions that are strongly influenced by changes in the environment and lifestyle. In particular, metabolic syndrome, a condition increasing in prevalence around the world, is one such condition for which epigenetics is postulated to contribute. Epigenetic defects (epimutations) are thought to be more easily reversible (when compared with genetic defects) and, as such, have inspired efforts to identify novel compounds that correct epimutations or prevent progression to the disease state. These efforts have resulted in the development of a rapidly growing new field being referred to as epigenetic therapy. To date, 2 classes of drugs have received the most attention, that is, DNA methyltransferase inhibitors and histone deacetylase inhibitors; but recent data suggest that botanical sources may be a rich source of agents that can potentially modulate the epigenome and related pathways and potentially be useful in attenuating the progression of many factors related to development of metabolic syndrome. This review will provide an overview of the field of epigenetics, epigenetic therapy, and the molecules currently receiving the most interest with respect to treatment, and review data on botanical compounds that show promise in this regard.