Breast cancer resistance protein BCRP (ABCG2)-mediated transepithelial nitrofurantoin secretion and its regulation in human intestinal epithelial (Caco-2) layers.
Eur J Pharmacol
; 672(1-3): 70-6, 2011 Dec 15.
Article
en En
| MEDLINE
| ID: mdl-22004608
ABSTRACT
In order to determine the capacity and regulation of the breast cancer resistance protein (BCRP)-mediated transport in intact human intestinal epithelial monolayers (Caco-2) in which multiple ABC transporters are expressed, nitrofurantoin has been used as a selective transported substrate. Nitrofurantoin transepithelial secretion was confirmed in both human BCRP and mouse bcrp-transfected MDCKII epithelia, whereas no net transepithelial secretion was observed in native or human MDR1-MDCKII epithelia. Furthermore, nitrofurantoin transepithelial secretion by BCRP-MDCKII monolayers was inhibited by Ko143 (10 µM), but not verapamil (100 µM). In Caco-2 cells grown upon permeable supports, nitrofurantoin displayed a dose-dependent transepithelial secretion with an apparent Km=69.41 ± 22.3 µM and Vmax=14.03 ± 2.27 nmol/(cm(2).h). Net nitrofurantoin transepithelial secretion by Caco-2 epithelia was inhibited 92% by 10 µM Ko143. Regulation of expression and function of BCRP in Caco-2 epithelial monolayers was determined after 72-h pre-exposure of the monolayers to a number of potential inducing agents. Quantitative real-time PCR and Western blotting were used to correlate induction of BCRP transcript and protein levels with transport activity. 72-h pre-treatment with ß-napthoflavone and rosiglitazone up-regulates BCRP mRNA and protein expression and transport of nitrofurantoin. Ko143-sensitive transepithelial secretion of the bi-substrate (MDR1/BCRP) prazosin was also increased in the presence of rosiglitazone. We conclude that nitrofurantoin may be used to unambiguously measure BCRP-mediated fluxes in Caco-2 epithelial layers. Since dynamic regulation of BCRP expression and function is retained, the Caco-2 cell-line is useful as a screen for drug-drug and drug-diet interactions mediated by BCRP.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Transportadoras de Casetes de Unión a ATP
/
Mucosa Intestinal
/
Proteínas de Neoplasias
/
Nitrofurantoína
Límite:
Animals
/
Humans
Idioma:
En
Revista:
Eur J Pharmacol
Año:
2011
Tipo del documento:
Article
País de afiliación:
Reino Unido