Department of Human Biology, NUTRIM School for Nutrition, Toxicology and Metabolism, Maastricht University Medical Center+ Maastricht, The Netherlands.
Am J Clin Nutr. 2013 Jul;98(1):57-64. doi: 10.3945/ajcn.113.059022. Epub 2013 May 29.
Studies in rodents have shown that brown adipose tissue (BAT) is activated on food intake, thereby reducing metabolic efficiency.
The current study investigated whether a single high-calorie, carbohydrate-rich meal activates BAT in lean human adults.
BAT activity was studied in 11 lean adult men [age: 23.6 ± 2.1 y; body mass index (BMI; in kg/m(2)): 22.4 ± 2.1] after consumption of a high-calorie, carbohydrate-rich meal (1622 ± 222 kcal; 78% carbohydrate, 12% protein, 10% fat). BAT activity during 2 h of mild cold exposure served as a positive control experiment. BAT activity was assessed by [(18)F]fluorodeoxyglucose (FDG)-positron emission tomography-computed tomography. Energy expenditure was measured by indirect calorimetry.
Postprandial [(18)F]FDG uptake was significantly higher in BAT [1.65 ± 0.99 mean standard uptake value (SUVmean)] than in subcutaneous (0.35 ± 0.15 SUVmean; P < 0.05) and visceral (0.49 ± 0.24 SUVmean; P < 0.05) white adipose tissue and liver (0.95 ± 0.28 SUVmean; P < 0.05). Postprandial BAT activity was lower than cold-induced BAT activity (7.19 ± 2.09 SUVmean). However, postprandial BAT activity may have been underestimated because of high postprandial [(18)F]FDG uptake in skeletal muscle compared with cold (1.36 ± 0.31 compared with 0.59 ± 0.07 SUVmean, P < 0.05), which reduces [(18)F]FDG bioavailability for BAT and other tissues. No direct relation was found between BAT and diet-induced thermogenesis (DIT).
Glucose uptake in BAT increases after a meal in humans, which indicates a role for BAT in reducing metabolic efficiency. However, the quantitative contribution of BAT to DIT relative to other tissues, such as skeletal muscle, remains to be investigated. This trial was registered at www.controlled-trials.com as ISRCTN21413505.
研究表明，在进食时，啮齿动物的棕色脂肪组织（BAT）会被激活，从而降低代谢效率。
本研究旨在探讨高热量、富含碳水化合物的一餐是否会激活瘦人成年人的 BAT。
本研究共纳入 11 名瘦成年男性（年龄：23.6±2.1 岁；体重指数（BMI；kg/m2）：22.4±2.1），在摄入高热量、富含碳水化合物的餐后（1622±222 千卡；碳水化合物 78%，蛋白质 12%，脂肪 10%），检测其 BAT 活性。在轻度寒冷暴露下 2 小时内的 BAT 活性作为阳性对照实验。通过[18]F-氟脱氧葡萄糖（FDG）-正电子发射断层扫描-计算机断层扫描评估 BAT 活性。通过间接热量测定法测量能量消耗。
与皮下（0.35±0.15 SUVmean；P＜0.05）和内脏（0.49±0.24 SUVmean；P＜0.05）白色脂肪组织和肝脏（0.95±0.28 SUVmean；P＜0.05）相比，餐后 BAT 的[18]F-FDG 摄取量明显更高（1.65±0.99 平均标准摄取值（SUVmean））。餐后 BAT 活性低于寒冷诱导的 BAT 活性（7.19±2.09 SUVmean）。然而，由于与寒冷（1.36±0.31 比 0.59±0.07 SUVmean，P＜0.05）相比，餐后骨骼肌中摄取的[18]F-FDG 更高，可能低估了餐后 BAT 活性，这会降低 BAT 和其他组织中[18]F-FDG 的生物利用度。未发现 BAT 与饮食诱导产热（DIT）之间存在直接关系。
人类进食后 BAT 葡萄糖摄取增加，表明 BAT 在降低代谢效率方面发挥作用。然而，BAT 相对于其他组织（如骨骼肌）对 DIT 的贡献程度仍有待研究。本试验在 www.controlled-trials.com 上注册为 ISRCTN21413505。
