title: Detoxification enzyme activities (CYP1A1 and GST) in the skin of humpback whales as a function of organochlorine burdens and migration status.
abstract: The activities of glutathione-s-transferase (GST) and cytochrome P-450 1A1 (CYP1A1) enzymes were measured in freshly extracted epidermis of live-biopsied, migrating, southern hemisphere humpback whales (Megaptera novaeangliae). The two quantified enzyme activities did not correlate strongly with each other. Similarly, neither correlated strongly with any of the organochlorine compound groups previously measured in the superficial blubber of the sample biopsy core, likely reflecting the anticipated low levels of typical aryl-hydrocarbon receptor ligands. GST activity did not differ significantly between genders or between northward (early migration) or southward (late migration) migrating cohorts. Indeed, the inter-individual variability in GST measurements was relatively low. This observation raises the possibility that measured activities were basal activities and that GST function was inherently impacted by the fasting state of the sampled animals, as seen in other species. These results do not support the implementation of CYP1A1 or GST as effective biomarkers of organochlorine contaminant burdens in southern hemisphere populations of humpback whales as advocated for other cetacean species. Further investigation of GST activity in feeding versus fasting cohorts may, however, provide some insight into the fasting metabolism of these behaviourally adapted populations.
authors: Griffith University, School of Environment, Nathan, QLD 4111, Australia. Electronic address: s.bengtsonnash@griffith.edu.au.
authors: S
authors: S
authors: Bengtson Nash
authors: Griffith University, School of Environment, Nathan, QLD 4111, Australia.
authors: A
authors: A
authors: Dawson
authors: Griffith University, School of Environment, Nathan, QLD 4111, Australia.
authors: M
authors: M
authors: Burkhard
authors: University of the Sunshine Coast, Faculty of Science, Health, Education and Engineering, Sippy Downs, QLD 4558, Australia.
authors: C
authors: C
authors: Waugh
authors: Queensland University of Technology, Institute for Health and Biomedical Innovation (IHBI), Kelvin Grove, QLD 4059, Australia.
authors: W
authors: W
authors: Huston
mesh_terms: D000273:Adipose Tissue / Q000737:chemistry; D025041:Animal Migration / Q000502:physiology; D000818:Animals; D019363:Cytochrome P-450 CYP1A1 / Q000235:genetics / Q000378:metabolism*; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism*; D050640:Humpback Whale / Q000378:metabolism*; D006843:Hydrocarbons, Chlorinated / Q000032:analysis*; D008297:Male; D012867:Skin / Q000201:enzymology*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000633:toxicity*
chemical_list: D006843:Hydrocarbons, Chlorinated; D014874:Water Pollutants, Chemical; D019363:Cytochrome P-450 CYP1A1; D005982:Glutathione Transferase
keywords: Antarctica; CYP1A1; Epidermal enzyme activity; GST; Persistent organic pollutants; Southern hemisphere humpback whales (Megaptera novaeangliae)