The Effects of Chronic Manipulation of Proopiomelanocortin Neurons in Animal Models

项目摘要 这项建议旨在培养一名双学位DVM-博士学生，为她在职业生涯中取得成功做好准备。 独立的临床医生兼科学家。申请者将获得生物医学博士学位，同时 获得一张数字录像机。这项拟议的研究试图确定前阿片黑素皮质素(POMC)神经元在 下丘脑是能量平衡调节障碍潜在治疗的可行靶点， 包括肥胖和饮食失调。鉴于美国35%-40%的人患有肥胖症，2%-5%的人患有 对于饮食失调来说，我们更好地了解大脑如何调节能量是至关重要的 动态平衡。这项提议的长期目标是确定慢性操纵 下丘脑POMC神经元将纠正动物模型摄食量和体重的紊乱 能量平衡失调。将解决以下具体目标：1)确定长期的 在肥胖动物模型中刺激POMC神经元。2)确定长期抑制的影响 厌食症动物模型中的POMC神经元。慢性刺激对饲喂安慰剂的小鼠POMC神经元的影响 肥胖饮食(AIM 1)与活动型小鼠POMC神经元的慢性抑制 厌食行为分析(目标2)将使用化学遗传学(专门设计受体)来实现 由设计药物(DREADD)技术激活)。腺相关病毒技术将用于 向POMC神经元特异性递送刺激性hM3Dq(Aim 1)或抑制性hM4Di(Aim 2)DREADD 在下丘脑。氯氮平-n-氧化物，一种仅激活DREADDS的惰性配体，将被给予 通过可植入的、可编程的微输液泵，小鼠在离散的团注中。除了监控之外 生理终点，如体重和食物摄入量，RNAScope将用于确定程度 POMC神经元的激活或抑制。免疫组织化学将用于验证是否有足够的DREADD 在POMC神经元中表达。总之，这项研究提案将决定慢性操纵是否 POMC神经元将纠正在啮齿动物模型中观察到的摄食量和体重失调 肥胖和厌食症。此外，这项建议的结果将对今后旨在 开发能量平衡失调的治疗方法。

Project Summary This proposal seeks to train a dual degree, DVM-PhD, student to prepare her for success in a career as an independent clinician-scientist. The applicant will earn a PhD in Biomedical Sciences while simultaneously earning a DVM. The proposed research seeks to determine whether proopiomelanocortin (POMC) neurons in the hypothalamus are a viable target for potential therapies for disorders of energy balance regulation, including obesity and eating disorders. Given that 35-40% of people in the US are obese and 2-5% suffer from eating disorders, it is critically important that we better understand how the brain regulates energy homeostasis. The long-term objective of this proposal is to determine whether chronic manipulation of hypothalamic POMC neurons will correct disturbances in food intake and bodyweight in animal models of energy balance disorders. The following specific aims will be addressed: 1) Determine the impact of chronically stimulating POMC neurons in an animal model of obesity. 2) Determine the impact of chronically inhibiting POMC neurons in an animal model of anorexia. Chronic stimulation of POMC neurons in mice fed an obesogenic diet (Aim 1) and chronic inhibition of POMC neurons in mice undergoing the activity-based anorexia behavioral assay (Aim 2) will be achieved using chemogenetic (Designer Receptors Exclusively Activated by Designer Drugs (DREADD)) technology. Adeno-associated virus technology will be used to deliver either stimulatory hM3Dq (Aim 1) or inhibitory hM4Di (Aim 2) DREADDs specifically to POMC neurons in the hypothalamus. Clozapine-n-oxide, an inert ligand that only activates DREADDs, will be administered to mice in discrete boluses via implantable, programmable microinfusion pumps. In addition to monitoring physiological endpoints such as bodyweight and food intake, RNAscope will be used to determine the degree of POMC neuron activation or inhibition. Immunohistochemistry will be used to verify adequate DREADD expression in POMC neurons. Altogether, this research proposal will determine whether chronic manipulation of POMC neurons will correct the food intake and bodyweight disturbances observed in rodent models of obesity and anorexia. In addition, the results of this proposal will be of value for future studies aimed at developing therapies for energy balance disorders.