Roles of UDP-Glucuronosyltransferases in Phytochemical Metabolism of Herbal Medicines and the Associated Herb-Drug Interactions

UDP-glucuronosyltransferases (UGTs) play important roles in the disposition of many drugs and xenobiotics. Herbal medicine, an important group of multicomponent therapeutics, is widely and increasingly used. Drug metabolism of herbal medicine mediated by cytochrome P450s has been extensively studied; however, herbal medicine metabolism mediated by UGTs has not been adequately investigated. Thus, it is necessary to evaluate current evidence on the glucuronidation of herbal medicines by UGTs. In this review, the research advances of the potential for commonly used herbal medicines as UGT substrate and modulator are summarized. In addition, the herb-drug interactions associated with UGTs are also discussed.