Interaction of Food Additives with Intestinal Efflux Transporters

Breast cancer resistance protein (BCRP), multidrug resistance associated protein 2 (MRP2) and P-glycoprotein (P-gp) are ABC transporters that are expressed in the intestine, where they are involved in the efflux of many drugs from enterocytes back into the intestinal lumen. The inhibition of BCRP, MRP2, and P-gp can result in enhanced absorption and exposure of substrate drugs. Food additives are widely used by the food industry to improve the stability, flavor, and consistency of food products. Although they are considered safe for consumption, their interactions with intestinal transporters are poorly characterized. Therefore, in this study, selected food additives, including preservatives, colorants, and sweeteners, were studied in vitro for their inhibitory effects on intestinal ABC transporters. Among the studied compounds, several colorants were able to inhibit BCRP and MRP2, whereas P-gp was fairly insensitive to inhibition. Additionally, one sweetener was identified as a potent inhibitor of BCRP. Dose-response studies revealed that the IC₅₀ values of the inhibitors were lower than the estimated intestinal concentrations after the consumption of beverages containing food colorants. This suggests that there is potential for previously unrecognized transporter-mediated food additive-drug interactions.