Application of DNA Microarray in Studies of Herbal Dietary Supplements

Abstract

Herbal dietary supplements are used extensively worldwide and the consumption has dramatically increased in the United States in recent years. Although side effects of many herbal dietary supplements have been reported, safety assurance has not been addressed adequately and toxicological data on most herbal dietary supplements are lacking. To address the issue of human health protection, there are currently more than 30 herbal dietary supplements or active ingredients under study by the US National Toxicology Program (NTP). Herbal products often exhibit great variability in quality because of different processing methods, cultivation conditions, and harvest time, as well as the strain and species differences. Authentication of plant species used for preparation of herbal dietary supplements is a critical step of safety assurance. Botanical extracts differ from drugs in that they are mixtures of many active constituents. At present, there are no well-established methodologies for evaluating the toxicity or determining the toxic mechanisms of herbal plant extracts due to the complexity of chemical components. In this chapter, we describe the applications of DNA microarray for plant authentication and mechanistic studies of herbal dietary supplements. Keywords: authentication of plant species; gene expression; herbal dietary supplements; microarray; pathway analysis; toxicity