title: Effects of wintertime fasting and seasonal adaptation on AMPK and ACC in hypothalamus, adipose tissue and liver of the raccoon dog (Nyctereutes procyonoides).
abstract: The raccoon dog (Nyctereutes procyonoides) is a canid with autumnal fattening and passive wintering strategy. We examined the effects of wintertime fasting and seasonality on AMP-activated protein kinase (AMPK), a regulator of metabolism, and its target, acetyl-CoA carboxylase (ACC) on the species. Twelve farmed raccoon dogs (eleven females/one male) were divided into two groups: half were fasted for ten weeks in December-March (winter fasted) and the others were fed ad libitum (winter fed). A third group (autumn fed, eight females) was fed ad libitum and sampled in December. Total AMPK, ACC and their phosphorylated forms (pAMPK, pACC) were measured from hypothalamus, liver, intra-abdominal (iWAT) and subcutaneous white adipose tissues (sWAT). The fasted animals lost 32% and the fed 20% of their body mass. Hypothalamic AMPK expression was lower and pACC levels higher in the winter groups compared to the autumn fed group. Liver pAMPK was lower in the winter fasted group, with consistently decreased ACC and pACC. AMPK and pAMPK were down-regulated in sWAT and iWAT of both winter groups, with a parallel decline in pACC in sWAT. The responses of AMPK and ACC to fasting were dissimilar to the effects observed previously in non-seasonal mammals and hibernators. Differences between the winter fed and autumn fed groups indicate that the functions of AMPK and ACC could be regulated in a season-dependent manner. Furthermore, the distinctive effects of prolonged fasting and seasonal adaptation on AMPK-ACC pathway could contribute to the wintering strategy of the raccoon dog.
authors.affiliation: Department of Biology, University of Oulu, P.O. Box 3000, FI-90014, University of Oulu, Finland. Electronic address: sanni.kinnunen@oulu.fi.
authors.forename: Sanni
authors.initials: S
authors.lastname: Kinnunen
authors.affiliation: Finnish Institute of Occupational Health, Aapistie 1, FI-90220 Oulu, Finland.
authors.forename: Satu
authors.initials: S
authors.lastname: Mänttäri
authors.affiliation: Institute of Biomedicine, Biocenter Oulu, P.O. Box 5000, FI-90014, University of Oulu, Finland; Medical Research Center Oulu and Oulu University Hospital, Kajaanintie 50, FI-90220 Oulu, Finland.
authors.forename: Karl-Heinz
authors.initials: KH
authors.lastname: Herzig
authors.affiliation: Institute of Biomedicine/Anatomy, School of Medicine, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland; Department of Biology, Faculty of Science and Forestry, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland.
authors.forename: Petteri
authors.initials: P
authors.lastname: Nieminen
authors.affiliation: Institute of Biomedicine/Anatomy, School of Medicine, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio, Finland; Department of Biology, Faculty of Science and Forestry, University of Eastern Finland, P.O. Box 111, FI-80101 Joensuu, Finland.
authors.forename: Anne-Mari
authors.initials: AM
authors.lastname: Mustonen
authors.affiliation: Department of Biology, University of Oulu, P.O. Box 3000, FI-90014, University of Oulu, Finland.
authors.forename: Seppo
authors.initials: S
authors.lastname: Saarela
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000378:metabolism*; D000064:Acclimatization / Q000502:physiology*; D000103:Acetyl-CoA Carboxylase / Q000378:metabolism*; D054392:Adipokines / Q000097:blood; D000273:Adipose Tissue / Q000378:metabolism; D000818:Animals; D004734:Energy Metabolism / Q000502:physiology; D005215:Fasting / Q000097:blood / Q000378:metabolism*; D005260:Female; D006605:Hibernation / Q000502:physiology*; D007031:Hypothalamus / Q000378:metabolism; D007328:Insulin / Q000097:blood; D008099:Liver / Q000378:metabolism; D008297:Male; D046031:Raccoon Dogs / Q000097:blood / Q000378:metabolism*; D012621:Seasons
chemical_list: D054392:Adipokines; D007328:Insulin; D055372:AMP-Activated Protein Kinases; D000103:Acetyl-CoA Carboxylase
keywords: ACC; AMPK; Energy metabolism; Fasting; Seasonality