title: Biomarkers of organic contamination in the South American fish Poecilia vivipara and Jenynsia multidentata.
abstract: South American cyprinodontiform fish are potential candidates to be used as model biomarker species of exposure in environmental toxicology. The aim of this study was to identify molecular and biochemical biomarkers of pollution using Poecilia vivipara (Poecilidae) and Jenynsia multidentata (Anablepidae). Partial nucleotide sequences for cytochrome P-450 1A (CYP1A), a classical biomarker of exposure to organic contaminants in fish, were identified in P. vivipara and J. multidentata (approximately 650 nucleotides) using degenerated primers and polymerase chain reaction (PCR). These sequences shared approximately 90% identity in the predicted amino acid sequence with the corresponding CYP1A region of Fundulus heteroclitus. Real-time quantitative PCR (RT-qPCR) analysis confirmed that CYP1A transcription was markedly induced in the liver and gills of J. multidentata (approximately185-fold and 20-fold, respectively) and P. vivipara (122-fold and 739-fold, respectively) 24 h after exposure to 1 μM synthetic CYP1A inducer β-naphthoflavone (BNF). At 24 h after injection with 1 μg/g environmental carcinogenic contaminant benzo[a]pyrene (BaP), a decreased total antioxidant capacity against peroxyl radicals was observed both in liver of J. multidentata and gills of P. vivipara. BaP injection in both fish did not produce changes in lipid peroxide (thiobarbituric acid-reactive substances, TBARS) levels, suggesting an absence of an oxidative stress condition. The newly identified CYP1A may thus serve as general biomarker of exposure to organic contaminant in future studies using P. vivipara and J. multidentata. Data also indicate the importance of species-specific differences in biomarker responses in these South American cyprinodontiform fish, suggesting distinct resistance/susceptibility properties to polycyclic aromatic hydrocarbons.
authors.affiliation: Instituto de Ciências Biológicas, Universidade Federal do Rio Grande-FURG, Rio Grande, RS, Brazil.
authors.forename: Roger
authors.initials: R
authors.lastname: Stacke Ferreira
authors.forename: José Maria
authors.initials: JM
authors.lastname: Monserrat
authors.forename: Josencler Luís
authors.initials: JL
authors.lastname: Ribas Ferreira
authors.forename: Ana Cristina
authors.initials: AC
authors.lastname: Kalb
authors.forename: John
authors.initials: J
authors.lastname: Stegeman
authors.forename: Afonso Celso
authors.initials: AC
authors.lastname: Dias Bainy
authors.forename: Juliano
authors.initials: J
authors.lastname: Zanette
mesh_terms: D000818:Animals; D001564:Benzo(a)pyrene / Q000633:toxicity; D015415:Biomarkers; D003532:Cyprinodontiformes / Q000145:classification / Q000378:metabolism*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D029941:Fish Proteins / Q000235:genetics / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D005880:Gills / Q000201:enzymology / Q000378:metabolism; D008099:Liver / Q000201:enzymology / Q000378:metabolism; D008297:Male; D013020:South America; D013045:Species Specificity; D014158:Transcription, Genetic; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D019324:beta-Naphthoflavone / Q000633:toxicity
chemical_list: D015415:Biomarkers; D029941:Fish Proteins; D014874:Water Pollutants, Chemical; D001564:Benzo(a)pyrene; D019324:beta-Naphthoflavone; D003577:Cytochrome P-450 Enzyme System