Comprehensive Validation of CYP1A1/CYP1A2 Induction by Health Foods in the Cultured Cells Expressing Reporter Gene

Abstract

Recently, the intake of health foods has been steadily increasing, in order to preserve health, and to cure and/or protect from diseases. At the same time, a noticeable increase in adverse drug reactions caused by health foods has been reported. Cytochrome P450 is a family of enzymes responsible for the metabolism of a wide variety of xenobiotics, including therapeutic agents and environmental chemicals. In this study, we investigated the effect of health foods on metabolism by using cultured cells expressing CYP1A1 and CYP1A2 gene reporters. Expressed CYP1A1 and CYP1A2 catalyze not only detoxification and activation of carcinogens but also the metabolism of drugs such as phenacetin and theophylline. Among 175 health food extracts examined, 20 extracts increased the CYP1A1 gene reporter activity, especially extracts of St John's wort, turmeric-containing health foods, garlic-containing health foods, and vitamin/mineral-containing health foods. In addition, these health foods increased CYP1A1 and CYP1A2 mRNA expression in HepG2 cells and human cryopreserved hepatocytes. These results indicate that health food-drug interactions might be mediated through CYP1A2 activities.