Abstract

Induction of cytochrome P450 (CYP) can cause drug-drug interactions and efficacy failure. Induction risk in liver and gut is typically inferred from experiments with plated hepatocytes. Organoids are physiologically relevant, multi-cellular structures originating from stem cells. Intestinal stem-cell derived organoids retain traits of normal gut physiology, such as an epithelial barrier and cellular diversity. Matched human enteroid and colonoid lines, generated from ileal and colon biopsies from two donors, were cultured in extracellular matrix for three days, followed by a single 48h treatment with rifampin, omeprazole, CITCO and phenytoin at concentrations that induce target genes in hepatocytes. Following treatment, mRNA was analyzed for induction of target genes. Rifampin induced CYP3A4; estimated EC₅₀ and E_max were 3.75 µM and 8.96-fold, respectively for ileal organoids, and 1.40 µM and 11.3-fold, respectively, for colon organoids. Ileal, but not colon organoids exhibited nifedipine oxidase activity, which was induced by rifampin up to 14-fold. The test compounds did not increase mRNA expression of CYP1A2, CYP2B6, MDR1 (Pgp), BCRP and UGT1A1 in ileal organoids. Whereas omeprazole induced CYP3A4 (up to 5.3-fold, geomean, n = 4 experiments), CAR activators phenytoin and CITCO did not. Omeprazole failed to induce CYP1A2 mRNA, but induced CYP1A1 mRNA (up to 7.7-fold and 15-fold in ileal and colon organoids, respectively, n = 4 experiments). Despite relatively high intra- and interexperimental variability, data suggest that the model yields induction responses which are distinct from hepatocytes and holds promise to enable evaluation of CYP1A1 and CYP3A4 induction in gut.

Significance Statement An adult intestinal stem-cell derived organoid model to test cytochrome P450 induction in gut was evaluated. Testing several prototypical inducers for mRNA induction of P450 isoforms, UGT1A1, Pgp and BCRP with both human colon and ileal organoids resulted in a range of responses, often distinct from those found in hepatocytes, indicating the potential for further development of this model as a physiologically relevant gut induction test system.