Aerobic Exercise Improves Food Reward Systems in Obese Rats via Insulin Signaling Regulation of Dopamine Levels in the Nucleus Accumbens
Aerobic Exercise Improves Food Reward Systems in Obese Rats via Insulin Signaling Regulation of Dopamine Levels in the Nucleus Accumbens
复制标题
DOI：
10.1021/acschemneuro.9b00022
复制
发表时间：
2019-06-01
影响因子：
5
通讯作者：
Hou, Lijuan
中科院分区：
文献类型：
--
作者：
Chen, Wei;Li, Juan;Hou, Lijuan
多巴胺能通路包括从腹侧被盖区到伏核的投射，构成了大脑奖励系统的核心。伏隔核多巴胺信号转导功能障碍导致的食物奖赏不足是肥胖的重要因素，可能与胰岛素信号转导有关。有氧运动对预防和治疗肥胖都有积极的作用。此外，体育锻炼对纹状体多巴胺稳态和改善外周和中枢神经系统的胰岛素敏感性也很重要。因此，我们假设有氧运动可能通过胰岛素信号增加伏隔核中的多巴胺水平，从而改善肥胖患者的食物回报。在本研究中，我们使用了一种高脂饮食诱导的肥胖大鼠模型。肥胖大鼠表现出进食或细胞外胰岛素诱导的伏隔核多巴胺基础浓度降低，胰岛素信号减弱，脂肪偏好增加。有趣的是，一项为期8周的有氧运动疗法扭转了这些症状。此外，我们注意到伏隔核中胰岛素Akt/GSK3-β信号转导显著增加。这些数据表明，有氧运动通过胰岛素信号转导促进伏隔核多巴胺水平的升高，这可能是运动抗肥胖的重要神经生物学机制。
The dopaminergic pathway, comprising projections from the ventral tegmental area to the nucleus accumbens, constitutes the core of the brain reward system. Insufficient food reward caused by dopamine signaling dysfunction in the nucleus accumbens is an important contributor to obesity and may be associated with insulin signaling. Aerobic exercise has a positive effect on both preventing and treating obesity. In addition, physical exercise is important in striatal dopamine homeostasis and improves insulin sensitivity in the peripheral and central nervous system. Therefore, we hypothesized that aerobic exercise may increase dopamine levels in the nucleus accumbens through insulin signaling, thus improving food reward in obesity. In the present study, we used a rat model of obesity, induced by high fat diet. Obese rats exhibited lower basic dopamine concentration in the nucleus accumbens induced by eating or extracellular insulin, attenuated insulin signaling, and increased fat preference. Interestingly, an 8-week aerobic exercise regimen reversed these symptoms. In addition, we noted a significant increase in insulin Akt/GSK3-beta signal transduction in the nucleus accumbens. These data demonstrate that aerobic exercise promotes dopamine levels in the nucleus accumbens through insulin signal transduction, which may constitute an important neurobiological mechanism of exercise against obesity.