Weight gain is associated with reduced striatal response to palatable food.
Weight gain is associated with reduced striatal response to palatable food.
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DOI：
10.1523/jneurosci.2105-10.2010
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发表时间：
2010-09-29
期刊：
影响因子：
--
通讯作者：
Bohon C
中科院分区：
文献类型：
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作者：
Stice E;Yokum S;Blum K;Bohon C
与奖励回路功能低下的个体会吃得过多以补偿奖励不足的理论相一致，与瘦人相比，肥胖的人纹状体 D2 受体较少，并且对可口食物摄入的纹状体反应较少，而纹状体对食物摄入的反应较低，预示着那些因多巴胺奖励回路信号减弱而存在遗传风险的人未来体重会增加。然而动物研究表明，摄入美味食物会导致 D2 受体下调、D2 敏感性降低和奖赏敏感性降低，这意味着暴饮暴食可能会导致纹状体反应性降低。因此，我们使用重复测量的功能磁共振成像（fMRI）来测试暴饮暴食是否会导致人类纹状体对可口食物摄入的反应性降低。结果表明，与体重稳定的女性相比，在 6 个月内体重增加的女性表现出纹状体对可口食物消耗的反应减少。总的来说，结果表明，奖励电路的低敏感性会增加暴饮暴食的风险，并且这种暴饮暴食可能会进一步削弱前馈过程中奖励电路的响应性。
Consistent with the theory that individuals with hypo-functioning reward circuitry overeat to compensate for a reward deficit, obese versus lean humans have fewer striatal D2 receptors and show less striatal response to palatable food intake, and low striatal response to food intake predicts future weight gain in those at genetic risk for reduced signaling of dopamine-based reward circuitry. Yet animal studies indicate that intake of palatable food results in down-regulation of D2 receptors, reduced D2 sensitivity, and decreased reward sensitivity, implying that overeating may contribute to reduced striatal responsivity. Thus, we tested whether overeating leads to reduced striatal responsivity to palatable food intake in humans using repeated-measures functional magnetic resonance imaging (fMRI). Results indicated that women who gained weight over a 6-month period showed a reduction in striatal response to palatable food consumption relative to weight stable women. Collectively, results suggest that low sensitivity of reward circuitry increases risk for overeating and that this overeating may further attenuate responsivity of reward circuitry in a feed-forward process.