Integrated Research and Treatment Center (IFB) AdiposityDiseases, University Medical Center, Leipzig, Germany.
Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany.
Eur J Nucl Med Mol Imaging. 2018 Jul;45(9):1618-1625. doi: 10.1007/s00259-018-4002-7. Epub 2018 Apr 7.
Although the mechanisms by which the central noradrenaline (NA) system influences appetite and controls energy balance are quite well understood, its relationship to changes in body weight remains largely unknown. The main goal of this study was to further clarify whether the brain NA system is a stable trait or whether it can be altered by dietary intervention.
We aimed to compare central NA transporter (NAT) availability in ten obese, otherwise healthy individuals with a body mass index (BMI) of 42.4 ± 3.7 kg/m (age 34 ± 9 years, four women) and ten matched non-obese, healthy controls (BMI 23.9 ± 2.5 kg/m, age 33 ± 10 years, four women) who underwent PET with the NAT-selective radiotracer (S,S)-[C]O-methylreboxetine (MRB) before and 6 months after dietary intervention.
MRI-based individual volume-of-interest analyses revealed an increase in binding potential (BP) in the insula and the hippocampus of obese individuals, which correlated well with changes in BMI (-3.3 ± 5.3%; p = 0.03) following completion of the dietary intervention. Furthermore, voxel-wise regression analyses showed that lower BP in these regions, but also in the midbrain and the prefrontal cortex, at baseline was associated with higher achieved weight loss (e.g., hippocampal area R = 0.80; p < 0.0001). No changes were observed in non-obese controls.
These first longitudinal interventional data on NAT availability in highly obese individuals indicate that the central NA system is modifiable. Our findings suggest that NAT availability before intervention could help predict the amount and success of weight loss in obese individuals and help adjust treatment options individually by allowing prediction of the benefit of a dietary intervention.
尽管中枢去甲肾上腺素（NA）系统影响食欲和控制能量平衡的机制已相当清楚，但它与体重变化的关系仍知之甚少。本研究的主要目的是进一步阐明中枢 NA 系统是稳定的特征还是可以通过饮食干预来改变。
我们旨在比较 10 名肥胖者（BMI 为 42.4±3.7kg/m²，年龄 34±9 岁，4 名女性）和 10 名匹配的非肥胖健康对照者（BMI 为 23.9±2.5kg/m²，年龄 33±10 岁，4 名女性）的中枢去甲肾上腺素转运体（NAT）的可用性。这些参与者在接受（S，S）-[C]O-甲基麦角环肽（MRB）的正电子发射断层扫描（PET）之前和饮食干预 6 个月后接受了 MRI 个体容积感兴趣区分析。
基于 MRI 的个体容积感兴趣区分析显示，肥胖者的岛叶和海马体的结合势（BP）增加，这与饮食干预完成后 BMI 的变化（-3.3±5.3%；p=0.03）很好地相关。此外，体素回归分析显示，这些区域（包括中脑和前额叶皮层）基线时的 BP 较低与实现的体重减轻幅度较大相关（例如，海马体面积 R=0.80；p<0.0001）。非肥胖对照组未观察到变化。
这些关于高度肥胖个体中 NAT 可用性的首个纵向干预性数据表明，中枢 NA 系统是可调节的。我们的研究结果表明，干预前的 NAT 可用性可以帮助预测肥胖个体的体重减轻量和成功率，并通过预测饮食干预的益处来帮助个体调整治疗方案。
