Chong P K, Jung R T, Scrimgeour C M, Rennie M J
Department of Medicine, Ninewells Hospital and Medical School, Dundee, Scotland.
Clin Endocrinol (Oxf). 1994 May;40(5):577-81. doi: 10.1111/j.1365-2265.1994.tb03007.x.
Weight gain had previously been thought to be due to increased calorie intake alone though no information on its effect on total energy expenditure is available in humans. We therefore assessed whether weight gain associated with glucocorticoids is due to a reduction in energy expenditure.
We performed an open study with 1 mg of betamethasone given orally twice a day for 21 days.
Seven healthy female volunteers, age range 26-55 years, body mass index 19 to 40, mean 27 kg/m2.
Total free living energy expenditure was measured by the doubly labelled water method (D2 18O), resting metabolic rate by ventilated hood indirect calorimetry and fat free mass from the dilution volume of oxygen-18 labelled water. Body composition and components of energy expenditure were assessed before and during the final 14 days of betamethasone administration.
Weight increased by a mean of 1.2 kg (P < 0.05) because of a significant rise in fat mass (1.5 kg) with no change in fat free mass. Resting metabolic rate remained unaltered on betamethasone but total energy expenditure increased in all subjects with a significant mean rise of 26% from 11.7 to 14.7 MJ/24 h (P < 0.05). The energy component of physical activity with thermogenesis increased on average 52% (from 5.8 to 8.9 MJ/24 h; P < 0.05). The rise in energy expenditure was still apparent after correction for the increase in body weight. Fasting respiratory quotient (RQ) increased from 0.81 to 0.86 with no change in fasting blood glucose. Betamethasone did not result in an energy sparing effect on the two components of energy expenditure studied.
Body weight increased on betamethasone entirely due to an increase in fat mass. This occurred despite a rise in total energy expenditure which involved specifically that component accounted for by physical activity plus thermogenesis. The most likely explanation is that betamethasone increased dietary energy intake significantly in excess of expenditure. We estimate that an average extra energy intake of 2.8 MJ/day would have had to be consumed for this rise in fat mass to occur even before taking into account the energy intake cost of the rise in expenditure.
以往认为体重增加仅归因于热量摄入增加，然而尚无关于其对人类总能量消耗影响的相关信息。因此，我们评估了与糖皮质激素相关的体重增加是否是由于能量消耗减少所致。
我们开展了一项开放性研究，让受试者每天口服1毫克倍他米松，每日两次，共服用21天。
7名健康女性志愿者，年龄在26至55岁之间，体重指数为19至40，平均为27kg/m²。
采用双标记水法（D2¹⁸O）测量自由生活状态下的总能量消耗，通过通风橱间接测热法测量静息代谢率，利用¹⁸O标记水的稀释体积测量去脂体重。在倍他米松给药的最后14天之前及期间评估身体成分和能量消耗的组成部分。
体重平均增加1.2千克（P<0.05），原因是脂肪量显著增加（1.5千克）而去脂体重未变。倍他米松治疗期间静息代谢率保持不变，但所有受试者的总能量消耗均增加，平均显著升高26%，从11.7 MJ/24小时增至14.7 MJ/24小时（P<0.05）。身体活动与产热的能量成分平均增加52%（从5.8 MJ/24小时增至8.9 MJ/24小时；P<0.05）。校正体重增加后，能量消耗的增加仍然明显。空腹呼吸商（RQ）从0.81增至0.86，空腹血糖无变化。倍他米松对所研究的两种能量消耗成分未产生能量节省效应。
服用倍他米松后体重增加完全是由于脂肪量增加。尽管总能量消耗增加，特别是身体活动加产热所占的能量消耗成分增加，但体重仍出现了增加。最可能的解释是倍他米松使饮食能量摄入显著增加，超过了能量消耗。我们估计，即使不考虑能量消耗增加所带来的能量摄入成本，脂肪量增加也需要平均每天额外摄入2.8 MJ的能量。
