Clinical Nutrition Research Centre, Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore; National University Health System, Centre for Translational Medicine, Yong Loo Lin School of Medicine National University of Singapore, Singapore.
Clinical Nutrition Research Centre, Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore; Department of Biochemistry Yong Loo Lin School of Medicine National University of Singapore, Singapore.
Nutrition. 2019 Apr;60:6-10. doi: 10.1016/j.nut.2018.08.015. Epub 2018 Sep 7.
It has been demonstrated that leptin influences the energy balance by regulating appetite and increasing energy expenditure (EE). However, the relationship between circulating leptin and EE is confounded owing to variations in body composition. The aim of this study was to determine the role of circulating leptin in energy regulation and to examine whether the leptin-mediated changes in EE are associated with adiposity among healthy adults living in Singapore.
We conducted a cross-sectional study of 300 participants (112 men). Resting metabolic rate (RMR) was measured by indirect calorimetry. Body composition (i.e., fat mass [FM] and fat-free mass [FFM]) was measured by dual-energy x-ray absorptiometry. Serum leptin levels were determined by radioimmunoassay.
There were strong correlations between circulating leptin levels, FM, and RMR in healthy men and women. After normalization of RMR by a power function model (kcal·kg FFM·d), the influence of FFM can be effectively removed. The normalized RMR was significantly associated with both FM (r = 0.28, P < 0.001) and log leptin (r = 0.35, P < 0.001). In the stepwise multiple regression analysis, leptin level is the major predictor for normalized RMR, accounting for 12% of the variation. In contrast, FM did not explain any variation in normalized RMR.
Leptin may be a more significant predictor of normalized RMR than FM per se. The contribution of FM to RMR could be via a mechanism that is related to leptin-dependent responses involved in energy homeostasis.
研究表明，瘦素通过调节食欲和增加能量消耗（EE）来影响能量平衡。然而，由于身体成分的变化，循环瘦素与 EE 之间的关系变得复杂。本研究旨在确定循环瘦素在能量调节中的作用，并检查健康成年人中瘦素介导的 EE 变化是否与肥胖有关。
我们对 300 名参与者（112 名男性）进行了横断面研究。通过间接测热法测量静息代谢率（RMR）。通过双能 X 射线吸收法测量身体成分（即脂肪量 [FM] 和去脂体重 [FFM]）。通过放射免疫法测定血清瘦素水平。
在健康男性和女性中，循环瘦素水平、FM 和 RMR 之间存在很强的相关性。通过幂函数模型（kcal·kg FFM·d）对 RMR 进行归一化后，可以有效地去除 FFM 的影响。归一化 RMR 与 FM（r=0.28，P<0.001）和 log 瘦素（r=0.35，P<0.001）均显著相关。在逐步多元回归分析中，瘦素水平是归一化 RMR 的主要预测因子，占变异的 12%。相比之下，FM 不能解释归一化 RMR 的任何变异。
与 FM 本身相比，瘦素可能是归一化 RMR 的更重要预测因子。FM 对 RMR 的贡献可能是通过与瘦素依赖性反应相关的机制来实现的，这些反应涉及能量稳态。
