Enzyme activity and liver tissue PCB concentrations of chicks of northern fulmars (F. glacialis) and black-legged kittiwakes (R. tridactyla) from Kongsfjorden

• Main Authors: Helgason, Lisa Bjørnsdatter, Arukwe, Augustine, Gabrielsen, Geir W, Harju, Mikael, Hegseth, Marit Nøst, Heimstad, Eldbjørg S, Jørgensen, Even H, Mortensen, Anne S, Wolkers, Johannes
• Format: Other/Unknown Material
• Language: English
• Published: PANGAEA 2010
• Subjects: Biological sample; BIOS; International Polar Year (2007-2008); IPY; Kongsfjorden_2006_BIOS; Kongsfjorden; Spitsbergen; Arctic; Black-legged Kittiwake; Fulmarus glacialis; International Polar Year; Kongsfjord*; Northern Fulmar; rissa tridactyla; Svalbard
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.811083; https://doi.org/10.1594/PANGAEA.811083

Arctic seabirds are exposed to a wide range of halogenated organic contaminants (HOCs). Exposure occurs mainly through food intake, and many pollutants accumulate in lipid-rich tissues. Little is known about how HOCs are biotransformed in arctic seabirds. In this study, we characterized biotransformation enzymes in chicks of northern fulmars (Fulmarus glacialis) and black-legged kittiwakes (Rissa tridactyla) from Kongsfjorden (Svalbard, Norway). Phase I and II enzymes were analyzed at the transcriptional, translational and activity levels. For gene expression patterns, quantitative polymerase chain reactions (qPCR), using gene-sequence primers, were performed. Protein levels were analyzed using immunochemical assays of western blot with commercially available antibodies. Liver samples were analyzed for phase I and II enzyme activities using a variety of substrates including ethoxyresorufin (cytochrome (CYP)1A1/1A2), pentoxyresorufin (CYP2B), methoxyresorufin (CYP1A), benzyloxyresorufin (CYP3A), testosterone (CYP3A/CYP2B), 1-chloro-2,4-nitrobenzene (CDNB) (glutathione S-transferase (GST)) and 4-nitrophenol (uridine diphosphate glucuronyltransferase (UDPGT)). In addition, the hydroxylated (OH-) polychlorinated biphenyls (PCBs) were analyzed in the blood, liver and brain tissue, whereas the methylsulfone (MeSO2-) PCBs were analyzed in liver tissue. Results indicated the presence of phase I (CYP1A4/CYP1A5, CYP2B, and CYP3A) and phase II (GST and UDPGT) enzymes at the activity, protein and/or mRNA level in both species. Northern fulmar chicks had higher enzyme activity than black-legged kittiwake chicks. This in combination with the higher XOH-PCB to parent PCB ratios suggests that northern fulmar chicks have a different biotransformation capacity than black-legged kittiwake chicks.