1 FOOD ADDITIVES AS INHIBITORS OF INTESTINAL DRUG TRANSPORTER OATP2B1 Alli Tikkanen1, Estelle Pierrot1, Feng Deng1,2, Virginia Barras Sánchez1, Marja Hagström1, Jan B. Koenderink3, Heidi Kidron1* 1Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, 00014 Helsinki, Finland 2 Current address: Department of Clinical Pharmacology, Faculty of Medicine, University of Helsinki 3 Radboud University Medical Center, Department of Pharmacology and Toxicology, Nijmegen, The Netherlands *corresponding author Telephone: +358405666660 Email:
[email protected] 2 FOR TABLE OF CONTENTS USE ONLY FOOD ADDITIVES AS INHIBITORS OF INTESTINAL DRUG TRANSPORTER OATP2B1 Alli Tikkanen, Estelle Pierrot, Feng Deng, Virginia Barras Sánchez, Marja Hagström, Jan B. Koenderink, Heidi Kidron 3 ABSTRACT Food additives are compounds that are added to food and beverage to improve taste, color, preservation or composition. Generally, food additives are considered safe for human use due to safety evaluation conducted by food safety authorities and high safety margins applied to permitted usage levels. However, the interaction potential of food additives with simultaneously administered medication has not received much attention. Even though many food additives are poorly absorbed into systemic circulation, high concentrations could exist in the intestinal lumen making intestinal drug transporters, such as the uptake transporter organic anion transporting polypeptide 2B1 (OATP2B1), a possible site of food additive–drug interaction. In the present work, we aimed to characterize the interaction of a selection of 25 food additives including colorants, preservatives and sweeteners with OATP2B1 in vitro. In HEK293 cells transiently overexpressing OATP2B1 or control, uptake of dibromofluorescein was studied with and without 50 µM food additive at pH 7.4.