DIET/NUTRIENT INTERACTIONS WITH DRUG TRANSPORTERS

Dietary and nutrient-containing mixtures of phytochemicals may alter drug pharmacokinetics. Previous food-drug interaction studies have focused primarily on the effects of diet on drug-metabolizing enzymes. In recent years, the role of drug transporters in diet-drug interactions have been increasingly recognized. Modulation of drug transporters by diet/dietary supplements, such as St. John’s Wort, grapefruit juice, and green tea, may result in clinically important drug interactions. Flavonoids and isothiocyanates have also been identified as potent inhibitors/inducers of major efflux or uptake transporters. However, it remains difficult to predict alterations in drug disposition due to the complex components in foods/dietary supplements and multiple factors influencing drug disposition. In the present chapter, we focus on the molecular mechanisms of drug-dietary component interactions involving drug transporters, based on in vitro and in vivo studies, with specific emphasis on several major efflux transporters (P-glycoprotein, MRP, and BCRP) and uptake transporters (OATP, OAT).