Bariatric surgery induces alterations in effective connectivity between the orbitofrontal cortex and limbic regions in obese patients
Bariatric surgery induces alterations in effective connectivity between the orbitofrontal cortex and limbic regions in obese patients
复制标题
减肥手术导致肥胖患者眶额皮质和边缘区域之间有效连接的改变
DOI：
10.1007/s11432-019-2817-x
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发表时间：
2020-05-27
影响因子：
8.8
通讯作者：
Zhang, Yi
中科院分区：
文献类型：
--
作者：
Duan, Shijun;Ji, Gang;Zhang, Yi
肥胖受试者在动机和奖励神经回路中表现出增强的大脑反应，包括感觉和躯体整合-拦截、动机-奖励（纹状体）、情绪和记忆过程，这些过程在食物提示时减弱额叶区域的激活。减肥手术（BS）是治疗病态肥胖唯一可靠的方法。不幸的是，目前还不清楚BS是如何影响减肥后的神经回路的。我们的目的是研究BS对涉及奖励和动机处理、情绪、记忆和肠-脑相互作用的脑区基础活动的影响。我们将静息状态fMRI与低频波动幅度（ALFF）和格兰杰因果分析（GCA）相结合，评估了16名肥胖受试者（OB）和22名正常体重受试者（NW）额叶-中脑边缘回路区域之间的相互作用。OB组在基线和BS后1个月进行研究。比较OB与NW，以及BS前后ALFF在驱动（尾状核、眶额皮质（OFC））、唤醒（丘脑）和条件反射/记忆（杏仁核、海马）相关区域的差异有统计学意义（P < 0.05， FDR校正）。GCA显示，在OB组中，OFC与边缘区域（杏仁核、海马体和内侧丘脑）和尾状核有更大的连通性。BS后，OFC与边缘区域的连通性下降，而杏仁核和海马体与尾状核和丘脑的连通性增强，特别是在体重指数（BMI）较低的受试者中。OB组的OFC激活与术前BMI相关，术后OFC的变化与BMI的变化相关。总的来说，OFC的功能连通性明显下降。由于OFC对显著性归因很重要，并且与BS后参与情绪反应和条件反射的边缘脑区域相连，因此其与BMI变化的显著关联表明OFC变化对术后饮食行为控制的改善有贡献。
Obese subjects show enhanced brain responses in motivation and reward neurocircuitry encompassing sensory and somatic integration-interception, motivation-reward (striatal), emotion, and memory processes, which attenuate frontal region activation during food cues. Bariatric surgery (BS) is the only reliable treatment for morbid obesity. Unfortunately, it is unknown how BS affects neurocircuitry after weight loss. We aimed to examine effects of BS on the basal activity of brain areas involved in reward and motivation processing, emotion, memory, and gut-brain interaction. We combined resting-state fMRI with amplitude of low-frequency fluctuation (ALFF) and Granger causality analysis (GCA) to assess interactions between regions within the frontal-mesolimbic circuitry in 16 obese subjects (OB) and 22 normal-weight (NW) subjects. The OB group was studied at baseline and 1 month post BS. Comparisons between OB and NW, and pre-and post BS showed significant differences in ALFF in areas involved in drive (caudate, orbitofrontal cortex (OFC)), arousal (thalamus), and conditioning/memory (amygdala, hippocampus) (P < 0.05, FDR correction). GCA revealed that in the OB group, the OFC had greater connectivity to limbic regions (amygdala, hippocampus, and medial thalamus) and the caudate. Post BS, the connectivity of the OFC to limbic regions decreased, whereas the connectivity from the amygdala and hippocampus to the caudate and thalamus was enhanced, particularly in subjects with lower body mass index (BMI). OFC activation in the OB group was associated with BMI prior to surgery, and changes in OFC post surgery were associated with alterations in BMI. Overall, the functional connectivity of the OFC was significantly decreased. As it is important for salience attribution and connected to limbic brain regions involved with emotional reactivity and conditioning after BS, its significant association with BMI changes indicates the contribution of OFC changes to the improved control of eating behavior after surgery.