title: Real-time analysis of P-glycoprotein-mediated drug transport across primary intestinal epithelium three-dimensionally cultured in vitro.
abstract: P-glycoprotein (P-gp) is an efflux transporter that regulates bioavailability of orally administered drugs at the intestinal epithelium. To develop an in vitro experimental model that mimics P-gp-mediated intestinal drug transport in vivo, we employed normal intestinal epithelium three-dimensionally cultured. Physiological expression of P-gp mRNA and the expression of its protein at the apical membrane were observed in the small intestinal epithelium grown as cystic organoids. Rhodamine123 (Rh123), a substrate for P-gp, was actively transported in the basoapical direction and accumulated in the luminal space, while the epithelial integrity was kept intact. Furthermore, we were able to monitor the whole process of Rh123 transport and its inhibition by verapamil in real-time, from which kinetic parameters for Rh123 transport could be estimated by a mathematical modeling. The method here described to evaluate the dynamics of P-gp-mediated transport in primary intestinal epithelial cells would be instrumental in investigating the physiological function of P-gp and its inhibitors/inducers in vitro.
authors.affiliation: Department of Gastroenterology and Hepatology, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Mizutani
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Nakamura
authors.forename: Ryo
authors.initials: R
authors.lastname: Morikawa
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Fukuda
authors.forename: Wakana
authors.initials: W
authors.lastname: Mochizuki
authors.forename: Yuhki
authors.initials: Y
authors.lastname: Yamauchi
authors.forename: Kengo
authors.initials: K
authors.lastname: Nozaki
authors.forename: Shiro
authors.initials: S
authors.lastname: Yui
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Nemoto
authors.forename: Takashi
authors.initials: T
authors.lastname: Nagaishi
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Okamoto
authors.forename: Kiichiro
authors.initials: K
authors.lastname: Tsuchiya
authors.forename: Mamoru
authors.initials: M
authors.lastname: Watanabe
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism*; D000818:Animals; D001682:Biological Availability; D001692:Biological Transport; D018929:Cell Culture Techniques; D002478:Cells, Cultured; D005456:Fluorescent Dyes / Q000493:pharmacokinetics; D007413:Intestinal Mucosa / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D008954:Models, Biological; D010599:Pharmacokinetics; D020112:Rhodamine 123 / Q000493:pharmacokinetics; D014700:Verapamil / Q000493:pharmacokinetics
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D005456:Fluorescent Dyes; D020112:Rhodamine 123; D014700:Verapamil