Section of Nuclear Medicine, Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil; Division of Medical Nutrition, Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
Division of Medical Nutrition, Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
Nutrition. 2020 Nov-Dec;79-80:110888. doi: 10.1016/j.nut.2020.110888. Epub 2020 Jun 2.
Imaging studies have shown brain abnormalities associated with eating behavior (taste perception, food intake, and food reward), neural connectivity, and cognition related to obesity. The aim of this study was to investigate whether obese individuals have changes in regional cerebral blood flow (rCBF) during fasting and rest using single-photon emission computed tomography (SPECT), and whether these differences are associated with body fat and serum levels of leptin, insulin, and glucose.
For this purpose, rCBF assessed by ([99]Tc)-ECD-SPECT was compared between 10 obese women (30 ± 5 y of age, body fat: 38 ± 3 kg) and 10 lean women (30 ± 6 y of age, body fat: 17 ± 5 kg) using statistical parametric mapping. Pearson's coefficient and linear regression were used to search for associations among variables.
The obese women showed antagonic rCBF in the left frontoparietal region and greater rCBF in areas related to the default mode network and the salience network (P = 0.0001). Positive linear correlations of rCBF, body fat, and the serum levels of glucose and insulin were found, but no associations were detected using linear regression.
Obese women showed rCBF differences in areas related to the frontoparietal neural circuit, the default mode network, and the salience network, suggesting loss of cognitive control and a higher perception of physiologic processes, such as hunger. Hyperactivation in these areas might jeopardize the recognition of changes in energy homeostasis.
影像学研究表明，与进食行为（味觉感知、食物摄入和食物奖励）、神经连接以及与肥胖相关的认知有关的大脑异常与肥胖有关。本研究旨在通过单光子发射计算机断层扫描（SPECT）研究肥胖个体在禁食和休息期间的局部脑血流（rCBF）是否发生变化，以及这些差异是否与体脂肪和血清瘦素、胰岛素和葡萄糖水平有关。
为此，使用统计参数映射比较了 10 名肥胖女性（30 ± 5 岁，体脂肪：38 ± 3 kg）和 10 名瘦女性（30 ± 6 岁，体脂肪：17 ± 5 kg）之间由 [99]Tc]-ECD-SPECT 评估的 rCBF。使用 Pearson 系数和线性回归搜索变量之间的关联。
肥胖女性的左额顶区域 rCBF 表现出拮抗作用，与默认模式网络和突显网络相关的区域 rCBF 更大（P = 0.0001）。rCBF、体脂肪和血糖、胰岛素血清水平呈正线性相关，但线性回归未发现相关性。
肥胖女性在与额顶神经回路、默认模式网络和突显网络相关的区域 rCBF 存在差异，这表明认知控制能力下降，对饥饿等生理过程的感知增强。这些区域的过度活跃可能会危及对能量平衡变化的识别。
