There are several clinically relevant instances of a food or dietary supplement altering the activity of a pharmaceutical agent. For example, St. John’s Wort (Hypericum perforatum), a popular herbal antidepressant, affects pharmacokinetic actions of HIV protease inhibitors, antidepressants,
antihypertensives, and oral contraceptives. Drug-nutrient interaction (DNI) represents a relationship between a medication and one or more nutrients, specific food components, or metabolic status. A component of a food or dietary supplement, such as a small bioactive chemical, can affect the overall
bioavailability of a drug by affecting its altered absorption, metabolism, and elimination. Small-molecule xenobiotics are metabolized in the liver and intestine by phase I and II drug-metabolizing enzymes (DMEs) and transport proteins, including influx (phase 0) and efflux (phase III) pathways. Genes involved in drug metabolism and disposition, including the predominant phase 1 enzyme system, cytochrome P450 (CYP), are transcriptionally regulated by xenobiotic-activated nuclear receptors (NRs) and transcription factors, such as PXR (pregnane X receptor), CAR (constitutive androstane receptor), FXR (farnesoid X receptor) VDR, (vitamin D receptor), AhR (aryl hyrdocarbon receptor), and Nrf2 (Nuclear factor erythroid 2-related factor 2). In general, activation of these xenobiotic receptors is considered to be predictive of a subsequent alteration in DME, which in turn impacts the bioavailability and activity of drugs and nutrients.
Date of publication: 2019
Author: Jack Vanden Heuvel, PhD; INDIGO Biosciences, Inc.