title: The first demonstration of CYP1A and the ABC protein(s) gene expression and activity in European seabass (Dicentrarchus labrax) primary hepatocytes.
abstract: Primary hepatocytes are a model for studying various effects of different xenobiotics, including detoxification strategies. In this study we have isolated and cultured European seabass (Dicentrarchus labrax) primary hepatocytes and assessed gene transcription and activity of CYP1A (phase I of cellular detoxification) and ABCC1 and ABCC2 (phase III) transport proteins after exposure to benzo(a)pyrene (BaP). A dose dependent increase in Abcc2 and Cyp1a mRNA transcripts was observed in seabass primary hepatocytes upon exposure to BaP. The activity of ABC proteins, as key mediators of the multixenobiotic resistance (MXR), was further confirmed by assessing the accumulation of the model fluorescence substrate rhodamine 123 in the absence and presence of model inhibitors. A weak interaction between BaP and ABC proteins was observed. CYP1A dependent ethoxyresorufin-O-deeethylase (EROD) activity was significantly induced by the presence of BaP. After the 24h exposure period only 10% of the initial BaP was present in the incubation medium, clearly demonstrating biotransformation potential of primary seabass hepatocytes. Furthermore, the presence of the 3-hydroxybenzo(a)pyrene, a BaP metabolite, in the medium implies its active efflux. In conclusion, we showed that seabass primary hepatocytes do express important elements of the cellular detoxification machinery and may be a useful in vitro model for studying basic cellular detoxification mechanisms and their interaction with environmental contaminants.
authors.affiliation: CIIMAR/CIMAR - Interdisciplinary Centre of Marine and Environmental Research, Laboratory of Environmental Toxicology, University of Porto, Rua dos Bragas, 289, 4050-123 Porto, Portugal. Electronic address: mferreira@ciimar.up.pt.
authors.forename: Marta
authors.initials: M
authors.lastname: Ferreira
authors.affiliation: CIIMAR/CIMAR - Interdisciplinary Centre of Marine and Environmental Research, Laboratory of Environmental Toxicology, University of Porto, Rua dos Bragas, 289, 4050-123 Porto, Portugal; ICBAS/UP - Institute of Biomedical Sciences Abel Salazar, University of Porto, Largo Professor Abel Salazar, 2, 4099-003 Porto, Portugal; Faculty of Sciences, University of Porto, Rua do Campo Alegre s/n, 4169-007 Porto, Portugal.
authors.forename: Pedro
authors.initials: P
authors.lastname: Santos
authors.affiliation: CIIMAR/CIMAR - Interdisciplinary Centre of Marine and Environmental Research, Laboratory of Environmental Toxicology, University of Porto, Rua dos Bragas, 289, 4050-123 Porto, Portugal.
authors.forename: Ledicia
authors.initials: L
authors.lastname: Rey-Salgueiro
authors.affiliation: Laboratory for Molecular Ecotoxicology, Division for Marine and Environmental Research, Rudjer Boskovic Institute, Bijenicka 54, 10000 Zagreb, Croatia.
authors.forename: Roko
authors.initials: R
authors.lastname: Zaja
authors.affiliation: CIIMAR/CIMAR - Interdisciplinary Centre of Marine and Environmental Research, Laboratory of Environmental Toxicology, University of Porto, Rua dos Bragas, 289, 4050-123 Porto, Portugal.
authors.forename: Maria Armanda
authors.initials: MA
authors.lastname: Reis-Henriques
authors.affiliation: Laboratory for Molecular Ecotoxicology, Division for Marine and Environmental Research, Rudjer Boskovic Institute, Bijenicka 54, 10000 Zagreb, Croatia.
authors.forename: Tvrtko
authors.initials: T
authors.lastname: Smital
mesh_terms: D000818:Animals; D001492:Bass / Q000235:genetics* / Q000378:metabolism*; D001564:Benzo(a)pyrene / Q000633:toxicity; D002470:Cell Survival / Q000187:drug effects; D019363:Cytochrome P-450 CYP1A1 / Q000235:genetics / Q000378:metabolism*; D054750:Ecotoxicology; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D022781:Hepatocytes / Q000378:metabolism*; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic / Q000187:drug effects; D015262:Xenobiotics / Q000378:metabolism
chemical_list: D001564:Benzo(a)pyrene; D019363:Cytochrome P-450 CYP1A1; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D015262:Xenobiotics; C421109:multidrug resistance-associated protein 1
keywords: ABC transporters; Biotransformation; CYP1A; Detoxification; MXR