Characterization of EpiIntestinal Duodenum Microtissue as an In Vitro Model for Studying Intestinal Drug...

Area of Science:

• Drug Discovery and Development
• Gastrointestinal Physiology
• Pharmacokinetics

Background:

• Oral drug absorption is influenced by intestinal permeability, metabolism, and transporter activity.
• Accurate prediction of oral drug absorption is crucial for drug development.
• Existing models may not fully capture the complex interplay of these factors.

Purpose of the Study:

• To characterize the EpiIntestinal duodenum microtissue model derived from human duodenum enterocytes.
• To evaluate its capability in simultaneously investigating intestinal permeability, metabolism, and transport.
• To assess its utility in predicting oral drug absorption.

Main Methods:

• Primary human duodenum enterocytes were cultured on permeable supports to create microtissues.
• A panel of drugs with known human absorption was used to validate predictive capabilities.
• Protein expression and functional activities of key drug-metabolizing enzymes and transporters were analyzed using specific substrates and inhibitors.

Main Results:

• Microtissue permeability (Papp) correlated positively with human fraction absorbed (% Fa).
• Expression and function of efflux transporters (P-gp, BCRP, MRPs) and uptake transporter (PEPT1) were confirmed.
• Activities of major drug-metabolizing enzymes (CYP3A4/5, CYP2C19, CYP2C8, UGT1A1, SULT1B1) were demonstrated.
• The model revealed the dominant role of CYP3A4/5 over P-gp in nicardipine permeability.

Conclusions:

• The EpiIntestinal duodenum microtissue effectively models the gut's complex interplay of permeability, metabolism, and transport.
• This advanced model offers improved prediction of oral drug absorption.
• It represents a valuable tool for preclinical drug development.