Lips Mirjam A, Wijngaarden Marjolein A, van der Grond Jeroen, van Buchem Mark A, de Groot Gerrit H, Rombouts Serge A R B, Pijl Hanno, Veer Ilya M
From the Departments of Endocrinology & Metabolism (MAL, MAW, and HP) and Radiology (JvdG, MAvB, and SARBR), Leiden University Medical Center, Leiden, Netherlands; the Leiden Institute for Brain and Cognition (MAvB, SARBR, and IMV) and the Institute of Psychology (SARBR), Leiden University, Leiden, Netherlands; the Department of Gastroenterology, Rode Kruis Ziekenhuis, Beverwijk, Netherlands (GHdG); and the Division of Mind and Brain Research, Department of Psychiatry and Psychotherapy, Charité Universitätsmedizin Berlin, Berlin, Germany (IMV).
Am J Clin Nutr. 2014 Aug;100(2):524-31. doi: 10.3945/ajcn.113.080671. Epub 2014 Jun 25.
The brain is crucial for the control of food intake, reward, and energy homeostasis.
We hypothesized that 1) brain circuits involved in energy homeostasis and reward show different functional connectivity patterns between obese and lean individuals and 2) food intake affects functional connectivity differentially in obese and lean individuals. Therefore, we compared the connectivity of the hypothalamus, amygdala, and posterior cingulate cortex, each probing a distinct network related to energy homeostasis and reward, between obese subjects and lean subjects in the fasting state and after meal ingestion.
We acquired 3 Tesla resting-state functional magnetic resonance imaging scans after an overnight fast and after ingestion of a liquid mixed meal in 46 obese female participants [19 with normal glucose tolerance and 27 with type 2 diabetes mellitus (T2DM)] and 12 lean subjects. Functional connectivity of our regions of interest was assessed by using a seed-based correlation approach.
No significant differences between normal-glucose-tolerant and T2DM subjects were observed. In the fasting state, the total obese group had stronger hypothalamic connectivity with the medial prefrontal cortex and the dorsal striatum than did the lean subjects. The amygdala was differentially connected to the right insula in obese compared with lean subjects. Food intake dampened hypothalamic connectivity with the frontal regions in lean subjects, whereas these connections were barely affected in obese subjects.
Our results indicate that functional connectivity in several brain networks, particularly the homeostatic and cognitive control network and the reward network, was different between obese and lean subjects. In the fasting state, obesity appears to be associated with stronger functional connectivity between brain areas involved in cognitive control, motivation, and reward, whereas these connections are largely unaffected by food intake in obese compared with lean subjects.
大脑对于食物摄入、奖赏和能量平衡的控制至关重要。
我们假设：1）参与能量平衡和奖赏的脑回路在肥胖个体和瘦个体之间表现出不同的功能连接模式；2）食物摄入对肥胖个体和瘦个体的功能连接有不同影响。因此，我们比较了肥胖受试者和瘦受试者在禁食状态和进食后，下丘脑、杏仁核和后扣带回皮质的连接情况，每个脑区都探测了一个与能量平衡和奖赏相关的独特网络。
我们对46名肥胖女性参与者[19名糖耐量正常者和27名2型糖尿病（T2DM）患者]以及12名瘦受试者在禁食一夜后和摄入混合流食后进行了3特斯拉静息态功能磁共振成像扫描。通过基于种子点的相关方法评估感兴趣区域的功能连接。
糖耐量正常者和T2DM患者之间未观察到显著差异。在禁食状态下，肥胖组整体与内侧前额叶皮质和背侧纹状体的下丘脑连接比瘦受试者更强。与瘦受试者相比，肥胖者的杏仁核与右侧脑岛的连接存在差异。食物摄入减弱了瘦受试者下丘脑与额叶区域的连接，而肥胖受试者的这些连接几乎未受影响。
我们的结果表明，肥胖和瘦受试者之间几个脑网络的功能连接存在差异，特别是内稳态和认知控制网络以及奖赏网络。在禁食状态下，肥胖似乎与参与认知控制、动机和奖赏的脑区之间更强的功能连接有关，而与瘦受试者相比，这些连接在肥胖者中基本不受食物摄入的影响。
