A New Wrinkle on an Old Remedy

For many years, naturopaths and health-conscious individuals have recommended the consumption of grape seed extracts. Chemical analyses of grape seeds have provided a treasure trove of active ingredients including resveratrol, anthocyanins, pro-anthocyanins, and numerous terpenes. Many of these substances are potent antioxidants and there is reason to believe that they may have meaningful health benefits.

As one of the editors of the Journal of Medicinal Food, I was asked to review an article on the chemical activities of grape seed extracts. I then wrote an editorial describing the interesting findings in this study and their biological relevance. The most interesting aspect of this well-conducted analysis was the description of a wholly new mechanism of action for the substances found in grape seeds. What the authors found was that the chemical species in grape seed extracts influence gene expression through a process knows as histone acetylation. What makes this so interesting is the fact the histone acetylation is one of the fundamental regulators of genetic expression and a critical part of the new field of science known as epigenetics.

Epigenetics is the field of study that examines heritable attributes that are not incorporated into DNA sequence. These epi-phenomena take existing genes and determine whether or not they will actually be expressed. The reason that this is so important is that it shines a very bright light on the limitations of genomic analyses (studies that examine the DNA sequence in tissues). Clearly, if the consumption of foodstuffs (like grape seed) can alter gene expression then the use of genomic profiles to predict cellular behavior can only be viewed as highly simplistic.

We are continually impressed by the complexity of biology and are humbled when we consider the intersecting pathways that take us from gene to function.