The endocrine regulation of feeding in fish

在所有脊椎动物中，食物摄入的调节涉及由大脑和外周组织产生的复杂的食欲调节因子（ARFs）网络。arf影响大脑的进食中枢，刺激或抑制进食。尽管最近取得了进展，但我们目前对鱼类摄食调节的理解是有限的，并且基于少数模式物种，例如金鱼。然而，鱼类的种类和饮食/摄食习惯的多样性表明，在摄食的内分泌调节中存在物种特异性机制。我的研究通过研究几种海洋鱼类（如康纳鱼和鳐鱼）和淡水鱼类（如金鱼、鲤鱼）的arf，建立了鱼类摄食控制的综合互动模型。我正在进行的长期研究目标是识别和表征调节鱼类食欲和食物摄入的分子和生理机制，并研究它们如何受到营养状况、饮食、环境线索和生殖事件的调节。迄今为止，我的研究已经提供了令人信服的新证据，表明主要的种间差异发生在这些因子的结构、产生位点和作用机制上。我的项目是独一无二的，因为它是世界上为数不多的使用综合（从整个动物到基因）比较方法来研究淡水和海洋鱼类喂养的内分泌调节的项目之一。我们还使用各种互补技术，包括体内（注射，行为观察）和体外（克隆，qPCR, RNAseq，组织培养，酶测定，原位杂交）方法。我们的短期目标是：(1)表征温带和热带鱼的ARFs并评估ARFs之间的相互作用(2)研究禁食、饮食和运动对摄食和ARFs的影响；(3)研究肠道菌群与ARFs之间的相互作用；(4)研究环境变化和气候变化引起的潜在变化对取食和ARFs的影响；(5)评估ARFs在调节摄食和繁殖中的相互作用。这项研究将使我们能够建立一个通用的模型来阐明鱼类和脊椎动物摄食的内分泌调节及其对生长和繁殖的影响，为管理和提高鱼类的生长和繁殖提供新的方法，并了解不同鱼类如何应对具有生态重要性的环境压力（如全球变暖）。我们的结果将非常有益，并可能对当地和多国渔业和水产养殖业产生影响。

In all vertebrates, the regulation of food intake involves intricate networks of appetite-regulating factors (ARFs) produced by both brain and peripheral tissues. ARFs affect feeding centres in the brain, and either stimulate or inhibit feeding. Despite recent advances, our current understanding of the regulation of feeding in fish is limited and based on few model species, e.g. goldfish. However, the diversity in species and diets/feeding habits in fish suggests the existence of species-specific mechanisms in the endocrine regulation of feeding. My research has established comprehensive and interactive models of feeding control in fish by examining ARFs in several marine (i.e. cunner and skate) and freshwater (i.e. goldfish, characids) fish. The ongoing long-term goal of my research is to identify and characterize molecules and physiological mechanisms regulating appetite and food intake in fish, and to examine how they are modulated by nutritional status, diet, environmental cues and reproductive events. To date, my research has provided compelling new evidence that major interspecific differences occur in the structure, sites of production and mechanisms of action of these factors. My program is unique in that it is one of the few worldwide to use an integrative (from whole animal to genes) comparative approach to examine the endocrine regulation of feeding in both freshwater and marine fish. We also use a variety of complementary techniques, which include in vivo (injections, behavioral observations) and in vitro (cloning, qPCR, RNAseq, tissue culture, enzyme assays, in situ hybridization) methods. Our short-term objectives are to: (1) characterize ARFs in temperate and tropical fish and assess the interactions between ARFs (2) examine the effects of fasting, diets and exercise on feeding and ARFs; (3) examine the interactions between gut microbiota and ARFs; (4) examine the effects of environmental changes and potential climate change-induced variations on feeding and ARFs; (5) assess the interactions of ARFs in the regulation of feeding and reproduction. This research will allow us to establish a general model elucidating the endocrine regulation of feeding in fish and vertebrates and its impact on growth and reproduction, provide new approaches to manage and enhance growth and reproduction in fish and to understand how different fish species deal with environmental stressors of ecological importance (e.g. global warming). Our results will be highly beneficial and likely to have impact in the local and multi-national fishing and aquaculture industries.