title: Benzo(a)pyrene Metabolism and EROD and GST Biotransformation Activity in the Liver of Red- and White-Blooded Antarctic Fish.
abstract: Climate change and anthropogenic pollution are of increasing concern in remote areas such as Antarctica. The evolutionary adaptation of Antarctic notothenioid fish to the cold and stable Southern Ocean led to a low plasticity of their physiological functions, what may limit their capacity to deal with altered temperature regimes and pollution in the Antarctic environment. Using a biochemical approach, we aimed to assess the hepatic biotransformation capacities of Antarctic fish species by determining (i) the activities of ethoxyresorufin-O-deethylase (EROD) and glutathione-S-transferase (GST), and (ii) the metabolic clearance of benzo(a)pyrene by hepatic S9 supernatants. In addition, we determined the thermal sensitivity of the xenobiotic biotransformation enzymes. We investigated the xenobiotic metabolism of the red-blooded Gobionotothen gibberifrons and Notothenia rossii, the hemoglobin-less Chaenocephalus aceratus and Champsocephalus gunnari, and the rainbow trout Oncorhynchus mykiss as a reference. Our results revealed similar metabolic enzyme activities and metabolic clearance rates between red- and white-blooded Antarctic fish, but significantly lower rates in comparison to rainbow trout. Therefore, bioaccumulation factors for metabolizable lipophilic contaminants may be higher in Antarctic than in temperate fish. Likewise, the thermal adaptive capacities and flexibilities of the EROD and GST activities in Antarctic fish were significantly lower than in rainbow trout. As a consequence, increasing water temperatures in the Southern Ocean will additionally compromise the already low detoxification capacities of Antarctic fish.
authors.affiliation: †University of Basel, Departement of Environmental Sciences, Programme Man-Society-Environment MGU, Vesalgasse 1, CH-4051 Basel, Switzerland.|§University of Bern, Vetsuisse Faculty, Centre for Fish and Wildlife Health, Länggassstrasse 12, CH-3012 Bern, Switzerland.
authors.forename: Anneli
authors.initials: A
authors.lastname: Strobel
authors.affiliation: †University of Basel, Departement of Environmental Sciences, Programme Man-Society-Environment MGU, Vesalgasse 1, CH-4051 Basel, Switzerland.|∥Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2R3, Canada.
authors.forename: Patricia
authors.initials: P
authors.lastname: Burkhardt-Holm
authors.affiliation: ‡Empa, Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland.
authors.forename: Peter
authors.initials: P
authors.lastname: Schmid
authors.affiliation: §University of Bern, Vetsuisse Faculty, Centre for Fish and Wildlife Health, Länggassstrasse 12, CH-3012 Bern, Switzerland.
authors.forename: Helmut
authors.initials: H
authors.lastname: Segner
mesh_terms: D000064:Acclimatization; D000222:Adaptation, Physiological; D000818:Animals; D000864:Antarctic Regions; D001564:Benzo(a)pyrene / Q000378:metabolism / Q000493:pharmacokinetics*; D057231:Climate Change; D003080:Cold Temperature; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism*; D005260:Female; D005982:Glutathione Transferase / Q000378:metabolism*; D008658:Inactivation, Metabolic; D008099:Liver / Q000378:metabolism*; D008297:Male; D017686:Oncorhynchus mykiss / Q000378:metabolism; D010473:Perciformes / Q000378:metabolism* / Q000502:physiology; D014874:Water Pollutants, Chemical / Q000493:pharmacokinetics; D015262:Xenobiotics / Q000378:metabolism / Q000493:pharmacokinetics
chemical_list: D014874:Water Pollutants, Chemical; D015262:Xenobiotics; D001564:Benzo(a)pyrene; D019363:Cytochrome P-450 CYP1A1; D005982:Glutathione Transferase