Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
Department of Psychology, University of Pennsylvania, Philadelphia, PA 19104, USA.
Nutrients. 2021 May 13;13(5):1642. doi: 10.3390/nu13051642.
The mesencephalic trigeminal nucleus (Mes5) processes oral sensory-motor information, but its role in the control of energy balance remains unexplored. Here, using fluorescent in situ hybridization, we show that the Mes5 expresses the melanocortin-4 receptor. Consistent with MC4R activation in other areas of the brain, we found that Mes5 microinjection of the MC4R agonist melanotan-II (MTII) suppresses food intake and body weight in the mouse. Furthermore, NTS POMC-projecting neurons to the Mes5 can be chemogenetically activated to drive a suppression in food intake. Taken together, these findings highlight the Mes5 as a novel target of melanocortinergic control of food intake and body weight regulation, although elucidating the endogenous role of this circuit requires future study. While we observed the sufficiency of Mes5 MC4Rs for food intake and body weight suppression, these receptors do not appear to be necessary for food intake or body weight control. Collectively, the data presented here support the functional relevance of the NTS POMC to Mes5 projection pathway as a novel circuit that can be targeted to modulate food intake and body weight.
中脑三叉神经核 (Mes5) 处理口腔感觉运动信息，但它在能量平衡控制中的作用仍未被探索。在这里，我们使用荧光原位杂交技术表明 Mes5 表达了黑皮质素 4 受体。与大脑其他区域的 MC4R 激活一致，我们发现 Mes5 内注射 MC4R 激动剂黑素细胞刺激素-II (MTII) 可抑制小鼠的食物摄入和体重。此外，可化学遗传激活 NTS 投射到 Mes5 的 POMC 神经元以驱动食物摄入抑制。综上所述，这些发现强调了 Mes5 作为黑皮质素能控制食物摄入和体重调节的新靶点，尽管阐明该回路的内源性作用需要进一步研究。虽然我们观察到 Mes5 MC4R 足以抑制食物摄入和体重，但这些受体似乎不是食物摄入或体重控制所必需的。总的来说，这里呈现的数据支持 NTS POMC 到 Mes5 投射途径作为一种可以作为调节食物摄入和体重的新途径的功能相关性。
