Dulloo A G, Calokatisa R
Department of Physiology, University of Geneva, Switzerland.
Int J Obes. 1991 Jan;15(1):7-16.
Adaptive changes in energy expenditure (EE) in response to low calorie intake were assessed quantitatively in obese mice using techniques that measure EE chronically over weeks (by the comparative carcass method), and also over 24 h (by indirect calorimetry). Grossly obese mice were slimmed (by restricting food to 50 per cent of normal intake) until their body weight reached that of the lean. They were subsequently either maintained in the post-obese state by continued food restriction at 25 per cent below the obese controls, or refed at the same calorie intake as controls. Total EE (assessed over 3 week periods) fell by 30 per cent during weight loss (obese controls 1356 kJ vs obese-slimmed 966 kJ, P less than 0.001), by 25 per cent during maintenance of the post-obese weight (obese control 1443 kJ vs post-obese 1062 kJ, P less than 0.001), and remained diminished by 17 per cent during weight regain upon refeeding (obese control 1443 kJ vs slimmed/refed 1176 kJ, P less than 0.001). Similar reductions in daily oxygen consumption were also obtained by indirect calorimetry, and as a function of lean body mass, 24 h VO2 were lower than controls by 17 per cent, 9 per cent and 10 per cent respectively (P less than 0.01 at least), and remained so under conditions of locomotory restraint. It is calculated that in these obese mice, a metabolic component (unassociated with changes in lean body mass and activity) comprised nearly two-thirds of the adaptive fall in EE during weight loss, and one-half of the change in EE during both phases of post-obese weight maintenance and during weight regain. These studies therefore support the notion that in response to low calorie intake, adaptive changes in the efficiency of cellular energy utilization are of considerable quantitative importance in the resistance to weight loss and in the ease with which the obese condition is rapidly regained after slimming.
利用可在数周内长期测量能量消耗（EE）的技术（通过比较尸体重法）以及在24小时内测量能量消耗的技术（通过间接测热法），对肥胖小鼠因低热量摄入而产生的适应性变化进行了定量评估。严重肥胖的小鼠通过将食物限制在正常摄入量的50%来瘦身，直到其体重达到瘦小鼠的体重。随后，它们要么通过继续将食物摄入量限制在比肥胖对照组低25%的水平来维持肥胖后的状态，要么按照与对照组相同的热量摄入量重新喂食。在体重减轻期间，总能量消耗（在3周期间进行评估）下降了30%（肥胖对照组为1356千焦，肥胖瘦身组为966千焦，P<0.001）；在维持肥胖后体重期间下降了25%（肥胖对照组为1443千焦，肥胖后组为1062千焦，P<0.001）；在重新喂食体重恢复期间仍减少了17%（肥胖对照组为1443千焦，瘦身/重新喂食组为1176千焦，P<0.001）。通过间接测热法也获得了每日氧气消耗量的类似降低，并且作为瘦体重的函数，24小时的耗氧量分别比对照组低17%、9%和10%（至少P<0.01），并且在运动受限的条件下仍然如此。据计算，在这些肥胖小鼠中，一个代谢成分（与瘦体重和活动的变化无关）在体重减轻期间占能量消耗适应性下降的近三分之二，在肥胖后体重维持的两个阶段以及体重恢复期间占能量消耗变化的一半。因此，这些研究支持了这样一种观点，即响应低热量摄入，细胞能量利用效率的适应性变化在抵抗体重减轻以及肥胖状态在瘦身之后迅速恢复的难易程度方面具有相当大的定量重要性。
