title: Seasonal variation in the regulation of redox state and some biotransformation enzyme activities in the barn swallow (Hirundo rustica L.).
abstract: Little is known of the normal seasonal variation in redox state and biotransformation activities in birds. In long-distance migratory birds, in particular, seasonal changes could be expected to occur because of the demands of migration and reproduction. In this study, we measured several redox parameters in the barn swallow (Hirundo rustica L.) during the annual cycle. We captured the wintering barn swallows before spring migration in South Africa, and we captured the barn swallows that arrived in spring, bred in summer, and migrated in autumn in Finland. The redox status and biotransformation activities of barn swallows varied seasonally. Wintering birds in South Africa had high biotransformation activities and appeared to experience oxidative stress, whereas in spring and summer, they showed relatively low redox (superoxide dismutase [SOD], catalase [CAT], and glutathione reductase [GR]) and biotransformation enzyme activities. Autumn birds had very low biotransformation enzyme activities and low indication of oxidative stress but high activity of some redox enzymes (GR and glucose 6-phosphate dehydrogenase [G6PDH]). High activities of some redox enzymes (SOD, GR, and G6PDH) seem to be related to migration, whereas low activities of some redox enzymes (SOD, CAT, and GR) may be associated with breeding. Barn swallows in South Africa may experience pollution-related oxidative stress, which may hamper interpretation of normal seasonal variation in redox parameters.
authors.affiliation: Department of Biology, University of Turku, 20014 Turku, Finland. sari.raja-aho@turku.fi
authors.forename: Sari
authors.initials: S
authors.lastname: Raja-aho
authors.forename: Mirella
authors.initials: M
authors.lastname: Kanerva
authors.forename: Tapio
authors.initials: T
authors.lastname: Eeva
authors.forename: Esa
authors.initials: E
authors.lastname: Lehikoinen
authors.forename: Petri
authors.initials: P
authors.lastname: Suorsa
authors.forename: Kai
authors.initials: K
authors.lastname: Gao
authors.forename: Dalene
authors.initials: D
authors.lastname: Vosloo
authors.forename: Mikko
authors.initials: M
authors.lastname: Nikinmaa
mesh_terms: D025041:Animal Migration; D000818:Animals; D001711:Biotransformation; D002374:Catalase / Q000378:metabolism; D005387:Finland; D005954:Glucosephosphate Dehydrogenase / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism*; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D010088:Oxidoreductases / Q000378:metabolism*; D012621:Seasons; D013019:South Africa; D013482:Superoxide Dismutase / Q000378:metabolism; D046388:Swallows / Q000378:metabolism*
chemical_list: D010088:Oxidoreductases; D005954:Glucosephosphate Dehydrogenase; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D005980:Glutathione Reductase; D005982:Glutathione Transferase