title: Regulation of expression and activity of multidrug resistance proteins MRP2 and MDR1 by estrogenic compounds in Caco-2 cells. Role in prevention of xenobiotic-induced cytotoxicity.
abstract: ABC transporters including MRP2, MDR1 and BCRP play a major role in tissue defense. Epidemiological and experimental studies suggest a cytoprotective role of estrogens in intestine, though the mechanism remains poorly understood. We evaluated whether pharmacologic concentrations of ethynylestradiol (EE, 0.05pM to 5nM), or concentrations of genistein (GNT) associated with soy ingestion (0.1-10μM), affect the expression and activity of multidrug resistance proteins MRP2, MDR1 and BCRP using Caco-2 cells, an in vitro model of intestinal epithelium. We found that incubation with 5pM EE and 1μM GNT for 48h increased expression and activity of both MRP2 and MDR1. Estrogens did not affect expression of BCRP protein at any concentration studied. Irrespective of the estrogen tested, up-regulation of MDR1 and MRP2 protein was accompanied by increased levels of MDR1 mRNA, whereas MRP2 mRNA remained unchanged. Cytotoxicity assays demonstrated association of MRP2 and MDR1 up-regulation with increased resistance to cell death induced by 1-chloro-2,4-dinitrobenzene, an MRP2 substrate precursor, and by paraquat, an MDR1 substrate. Experiments using an estrogen receptor (ER) antagonist implicate ER participation in MRP2 and MDR1 regulation. GNT but not EE increased the expression of ERβ, the most abundant form in human intestine and in Caco-2 cells, which could lead in turn to increased sensitivity to estrogens. We conclude that specific concentrations of estrogens can confer resistance against cytotoxicity in Caco-2 cells, due in part to positive modulation of ABC transporters involved in extrusion of their toxic substrates. Although extrapolation of these results to the in vivo situation must be cautiously done, the data could explain tentatively the cytoprotective role of estrogens against chemical injury in intestine.
authors.affiliation: Instituto de Fisiología Experimental (IFISE-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas (UNR), Rosario, Santa Fe, Argentina.
authors.forename: Agostina
authors.initials: A
authors.lastname: Arias
authors.affiliation: Instituto de Fisiología Experimental (IFISE-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas (UNR), Rosario, Santa Fe, Argentina.
authors.forename: Juan Pablo
authors.initials: JP
authors.lastname: Rigalli
authors.affiliation: Instituto de Fisiología Experimental (IFISE-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas (UNR), Rosario, Santa Fe, Argentina.
authors.forename: Silvina S M
authors.initials: SS
authors.lastname: Villanueva
authors.affiliation: Instituto de Fisiología Experimental (IFISE-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas (UNR), Rosario, Santa Fe, Argentina.
authors.forename: María L
authors.initials: ML
authors.lastname: Ruiz
authors.affiliation: Instituto de Fisiología Experimental (IFISE-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas (UNR), Rosario, Santa Fe, Argentina.
authors.forename: Marcelo G
authors.initials: MG
authors.lastname: Luquita
authors.affiliation: Instituto de Fisiología Experimental (IFISE-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas (UNR), Rosario, Santa Fe, Argentina.
authors.forename: Virginia G
authors.initials: VG
authors.lastname: Perdomo
authors.affiliation: Graduate Center for Toxicology, University of Kentucky, Lexington, KY, USA.
authors.forename: Mary
authors.initials: M
authors.lastname: Vore
authors.affiliation: Instituto de Fisiología Experimental (IFISE-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas (UNR), Rosario, Santa Fe, Argentina.
authors.forename: Viviana A
authors.initials: VA
authors.lastname: Catania
authors.affiliation: Instituto de Fisiología Experimental (IFISE-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas (UNR), Rosario, Santa Fe, Argentina. Electronic address: amottino@unr.edu.ar.
authors.forename: Aldo D
authors.initials: AD
authors.lastname: Mottino
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D018938:Caco-2 Cells; D004137:Dinitrochlorobenzene / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D004965:Estrogen Antagonists / Q000494:pharmacology; D047629:Estrogen Receptor beta / Q000235:genetics; D004997:Ethinyl Estradiol / Q000008:administration & dosage / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects; D019833:Genistein / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D007413:Intestinal Mucosa / Q000187:drug effects / Q000378:metabolism; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D009363:Neoplasm Proteins / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D010269:Paraquat / Q000633:toxicity; D012333:RNA, Messenger / Q000378:metabolism; D013025:Glycine max / Q000737:chemistry; D015854:Up-Regulation / Q000187:drug effects; D015262:Xenobiotics / Q000633:toxicity
chemical_list: D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters; D004137:Dinitrochlorobenzene; D004965:Estrogen Antagonists; D047629:Estrogen Receptor beta; D004997:Ethinyl Estradiol; D019833:Genistein; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D009363:Neoplasm Proteins; D010269:Paraquat; D012333:RNA, Messenger; D015262:Xenobiotics; C513055:ABCB1 protein, human; C000715087:ABCC2 protein, human; C116614:ABCG2 protein, human
keywords: Estrogen receptor; Ethynylestradiol; Genistein; MDR1; MRP2