Duke Lemur Center, Durham, NC, USA.
Department of Biology, Duke University, Durham, NC, USA.
Proc Biol Sci. 2022 Jun 8;289(1976):20220598. doi: 10.1098/rspb.2022.0598. Epub 2022 Jun 15.
Fat-storing hibernators rely on fatty acids from white adipose tissue (WAT) as an energy source to sustain hibernation. Whereas arctic and temperate hibernators preferentially recruit dietary polyunsaturated fatty acids (PUFAs), tropical hibernators can rely on monounsaturated fatty acids that produce fewer lipid peroxides during oxidation. Nevertheless, compositional data on WAT from tropical hibernators are scant and questions remain regarding fat recruitment and metabolism under different environmental conditions. We analyse fatty acid profiles from the WAT of captive dwarf lemurs () subjected to high-sugar or high-fat diets during fattening and cold or warm conditions during hibernation. Dwarf lemurs fed high-sugar (compared to high-fat) diets displayed WAT profiles more comparable to wild lemurs that fatten on fruits and better depleted their fat reserves during hibernation. One PUFA, linoleic acid, remained elevated before hibernation, potentially lingering from the diets provisioned prior to fattening. That dwarf lemurs preferentially recruit the PUFA linoleic acid from diets that are naturally low in availability could explain the discrepancy between captive and wild lemurs' WAT. While demonstrating that minor dietary changes can produce major changes in seasonal fat deposition and depletion, our results highlight the complex role for PUFA metabolism in the ecology of tropical hibernators.
储能型冬眠动物依赖白色脂肪组织(WAT)中的脂肪酸作为能量来源来维持冬眠。而北极和温带的冬眠动物优先招募膳食多不饱和脂肪酸(PUFA),热带的冬眠动物则可以依赖单不饱和脂肪酸,这些脂肪酸在氧化过程中产生的脂质过氧化物较少。然而,关于热带冬眠动物 WAT 的组成数据很少,关于在不同环境条件下脂肪募集和代谢的问题仍然存在。我们分析了在育肥期间接受高糖或高脂肪饮食以及在冬眠期间接受冷或热条件的圈养侏儒狐猴()的 WAT 中的脂肪酸图谱。与高脂肪饮食相比,高糖饮食组的侏儒狐猴的 WAT 图谱更类似于在水果上育肥的野生狐猴,并且在冬眠期间更好地消耗了脂肪储备。一种多不饱和脂肪酸,亚油酸,在冬眠前仍然升高,可能是由于育肥前提供的饮食中残留的。侏儒狐猴优先从自然供应不足的饮食中招募多不饱和脂肪酸亚油酸,这可以解释圈养和野生狐猴 WAT 之间的差异。虽然我们的研究结果表明,饮食的微小变化可以对季节性脂肪沉积和消耗产生重大影响,但也强调了多不饱和脂肪酸代谢在热带冬眠动物生态学中的复杂作用。