Kinnunen Sanni, Mänttäri Satu, Herzig Karl-Heinz, Nieminen Petteri, Mustonen Anne-Mari, Saarela Seppo
Department of Biology, University of Oulu, P.O. Box 3000, FI-90014, University of Oulu, Finland.
Finnish Institute of Occupational Health, Aapistie 1, FI-90220 Oulu, Finland.
Comp Biochem Physiol A Mol Integr Physiol. 2016 Feb;192:44-51. doi: 10.1016/j.cbpa.2015.11.010. Epub 2015 Nov 18.
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.
貉（Nyctereutes procyonoides）是一种具有秋季育肥和被动越冬策略的犬科动物。我们研究了冬季禁食和季节性对代谢调节因子腺苷酸活化蛋白激酶（AMPK）及其靶点乙酰辅酶A羧化酶（ACC）在该物种上的影响。12只养殖貉（11只雌性/1只雄性）被分为两组：一半在12月至3月禁食10周（冬季禁食组），另一半自由采食（冬季采食组）。第三组（秋季采食组，8只雌性）自由采食并于12月取样。从下丘脑、肝脏、腹部内脏白色脂肪组织（iWAT）和皮下白色脂肪组织（sWAT）中测量总AMPK、ACC及其磷酸化形式（pAMPK、pACC）。禁食的动物体重减轻了32%，采食的动物体重减轻了20%。与秋季采食组相比，冬季组下丘脑AMPK表达较低，pACC水平较高。冬季禁食组肝脏pAMPK较低，ACC和pACC持续下降。两个冬季组的sWAT和iWAT中AMPK和pAMPK均下调，sWAT中pACC平行下降。AMPK和ACC对禁食的反应与之前在非季节性哺乳动物和冬眠动物中观察到得影响不同。冬季采食组和秋季采食组之间的差异表明，AMPK和ACC的功能可能以季节依赖性方式受到调节。此外，长期禁食和季节适应对AMPK-ACC途径的独特影响可能有助于貉的越冬策略。
