title: Biochemical responses in seabream (Sparus aurata) caged in-field or exposed to benzo(a)pyrene and paraquat. Characterization of glutathione S-transferases.
abstract: Gilthead seabream (Sparus aurata) specimens were caged in-field at the Téboulba harbour or exposed to benzo(a)pyrene [B(a)P] or to paraquat [PQ] plus B(a)P, and several biochemical biomarker responses were investigated. Antioxidant enzymes, such as glutathione peroxidase, catalase and glutathione reductase, significantly increased in the in-field and B(a)P+PQ exposures, but were only moderately affected by B(a)P alone. Glucose-6-phosphate and 6-phosphogluconate dehydrogenases significantly diminished after in-field exposure. Different responses with biotransformation enzymes were observed: the P4501A-associated EROD activity was highly induced in response to B(a)P and B(a)P+PQ exposures, while total activity of the glutathione S-transferase (GST) was similar to control. However, after purification of the GST proteins by affinity chromatograpy and analysis by two-dimensional electrophoresis, nineteen highly reproducible isoforms were resolved. In addition, some of reproducible isoforms showed different and specific expression patterns in response to contaminants. Thus, proteomic analysis of the purified GST subunits is a reliable tool for ecotoxicological research, useful in polluted marine ecosystem as an effective biomarker of contamination.
authors.affiliation: Laboratory of Biochemical and Environmental Toxicology, Higher Institute of Agriculture, Chott-Mariem, 4042-Sousse, Tunisia. jebali.jamel@laposte.net
authors.forename: Jamel
authors.initials: J
authors.lastname: Jebali
authors.forename: Eduardo
authors.initials: E
authors.lastname: Chicano-Gálvez
authors.forename: Mohamed
authors.initials: M
authors.lastname: Banni
authors.forename: Hamadi
authors.initials: H
authors.lastname: Guerbej
authors.forename: Hamadi
authors.initials: H
authors.lastname: Boussetta
authors.forename: Juan
authors.initials: J
authors.lastname: López-Barea
authors.forename: José
authors.initials: J
authors.lastname: Alhama
mesh_terms: D000818:Animals; D001564:Benzo(a)pyrene / Q000633:toxicity*; D015415:Biomarkers / Q000378:metabolism; D001711:Biotransformation; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism; D004798:Enzymes / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D005978:Glutathione / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism*; D018384:Oxidative Stress / Q000187:drug effects; D010269:Paraquat / Q000633:toxicity*; D040901:Proteomics; D021541:Sea Bream / Q000502:physiology*; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D015415:Biomarkers; D004798:Enzymes; D014874:Water Pollutants, Chemical; D001564:Benzo(a)pyrene; D019363:Cytochrome P-450 CYP1A1; D005982:Glutathione Transferase; D005978:Glutathione; D010269:Paraquat