Institute of Human Nutrition, Columbia University Irving Medical Center, New York, United States.
Department of Comparative Medicine, Yale University School of Medicine, New Haven, United States.
Elife. 2021 Mar 9;10:e64351. doi: 10.7554/eLife.64351.
The hypothalamic orexigenic Agouti-related peptide (AgRP)-expressing neurons are crucial for the regulation of whole-body energy homeostasis. Here, we show that fasting-induced AgRP neuronal activation is associated with dynamin-related peptide 1 (DRP1)-mediated mitochondrial fission and mitochondrial fatty acid utilization in AgRP neurons. In line with this, mice lacking in adult AgRP neurons (Drp1 cKO) show decreased fasting- or ghrelin-induced AgRP neuronal activity and feeding and exhibited a significant decrease in body weight, fat mass, and feeding accompanied by a significant increase in energy expenditure. In support of the role for mitochondrial fission and fatty acids oxidation, Drp1 cKO mice showed attenuated palmitic acid-induced mitochondrial respiration. Altogether, our data revealed that mitochondrial dynamics and fatty acids oxidation in hypothalamic AgRP neurons is a critical mechanism for AgRP neuronal function and body-weight regulation.
下丘脑食欲肽 Agouti 相关肽 (AgRP) 表达神经元对于全身能量稳态的调节至关重要。在这里,我们表明,饥饿诱导的 AgRP 神经元激活与 DRP1 介导的线粒体裂变和 AgRP 神经元中的线粒体脂肪酸利用有关。与此一致的是,成年 AgRP 神经元中缺失 dynamin-related peptide 1 (Drp1 cKO) 的小鼠表现出饥饿或胃饥饿素诱导的 AgRP 神经元活性和摄食减少,并表现出体重、脂肪量和摄食的显著减少,伴随着能量消耗的显著增加。支持线粒体裂变和脂肪酸氧化的作用,Drp1 cKO 小鼠显示出减弱的棕榈酸诱导的线粒体呼吸。总的来说,我们的数据表明,下丘脑 AgRP 神经元中的线粒体动力学和脂肪酸氧化是 AgRP 神经元功能和体重调节的关键机制。