Institute of Food and Nutrition Development, Ministry of Agriculture and Rural Affairs, Beijing, China.
Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China.
Front Endocrinol (Lausanne). 2022 Nov 1;13:1010472. doi: 10.3389/fendo.2022.1010472. eCollection 2022.
Agouti-related protein (AgRP) is a neuropeptide synthesized by AgRP/NPY neurons and transcribed as 132 amino acids in humans and 142 amino acids (AgRP1) in Japanese seabass () fish. AgRP neurons are activated by hormonal signals of energy deficits and inhibited by signals of energy surpluses and have been demonstrated to have the ability to sense the dynamics of blood glucose concentrations as the "glucose sensor" in mammals. It is widely recognized that AgRP is an endogenous antagonist of the melanocortin-3 and -4 receptors (MC3R and MC4R) in the hypothalamus, exhibiting potent orexigenic activity and control of energy homeostasis. Most fish, especially carnivorous fish, cannot make efficient use of carbohydrates. When carbohydrates like corn or wheat bran are added as energy sources, they often cause feeding inhibition and metabolic diseases. When fishmeal is replaced by plant protein, this does not completely eliminate carbs, limiting the utilization of carbohydrates and plant proteins in aquaculture. Our previous study showed that AgRP, and not neuropeptide Y (NPY) is the principal protein molecule that correlates well with feeding behavior in Japanese seabass from anorexia to adaptation. The Ghrelin/Leptin-mTOR-S6K1-NPY/AgRP/POMC feed intake regulatory pathway responds to the plant-oriented protein which contains glucose. However, its regulatory function and mechanism are still not clear. This review offers an integrative overview of how glucose signals converge on a molecular level in AgRP neurons of the arcuate nucleus of the hypothalamus. This is in order to control fish food intake and energy homeostasis.
阿黑皮素原（Agouti-related protein，AgRP）是一种由 AgRP/NPY 神经元合成的神经肽，在人类中被转录为 132 个氨基酸，在日本鲈鱼（）中被转录为 142 个氨基酸（AgRP1）。AgRP 神经元被能量缺乏的激素信号激活，被能量过剩的信号抑制，并被证明具有感知血糖浓度动态的能力，作为哺乳动物的“葡萄糖传感器”。人们普遍认为，AgRP 是下丘脑黑皮质素-3 和 -4 受体（MC3R 和 MC4R）的内源性拮抗剂，具有强烈的食欲刺激活性和能量稳态控制作用。大多数鱼类，特别是肉食性鱼类，不能有效地利用碳水化合物。当玉米或麦麸等碳水化合物作为能量来源添加时，它们往往会引起摄食抑制和代谢疾病。当用植物蛋白替代鱼粉时，这并不能完全消除碳水化合物，限制了碳水化合物和植物蛋白在水产养殖中的利用。我们之前的研究表明，AgRP 而不是神经肽 Y（neuropeptide Y，NPY），是与日本鲈鱼从厌食到适应的摄食行为密切相关的主要蛋白质分子。Ghrelin/Leptin-mTOR-S6K1-NPY/AgRP/POMC 摄食调节途径对含有葡萄糖的植物蛋白做出反应。然而，其调节功能和机制尚不清楚。本综述综合概述了葡萄糖信号如何在下丘脑弓状核的 AgRP 神经元在分子水平上汇聚，以控制鱼类的摄食和能量稳态。
