Role of the Lateral Hypothalamic Area in Leptin Action

下丘脑外侧区在瘦素作用中的作用

• 批准号: 7810340
• 负责人: Martin G Myers
• 金额: $ 23.44万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-01-01 至 2010-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7810340
• 关键词: Accounting; Acute; Alleles; Animals; Arousal; Award; Behavioral; Biological Assay; Body Weight; Brain; Brain region; Cell Nucleus; Cells; Data; Dopamine; Energy Metabolism; Epidemic; Food; Funding; Gene Expression; Genes; Genetic; Genetic Models; Genetic Transcription; Homeostasis; Human; Hypothalamic structure; Injection of therapeutic agent; Lateral; Lateral Hypothalamic Area; Leptin; Location; Mediating; Modeling; Mus; Neurobiology; Neurons; Neuropeptides; Neurophysiology - biologic function; Neurotensin; Neurotransmitters; Nucleus Accumbens; Obesity; Parents; Pathogenesis; Phenotype; Physiological; Play; Population; Preventive Intervention; Recovery; Regulation; Rewards; Rodent; Role; Rosa; Signal Transduction; Site; Structure of nucleus infundibularis hypothalami; Supplementation; System; Technology; Testing; Tracer; Transgenes; Transgenic Animals; United States; United States National Institutes of Health; Ventral Tegmental Area; design; dopamine system; dopaminergic neuron; energy balance; feeding; gamma-Aminobutyric Acid; genetic technology; hedonic; hypocretin; insight; interest; melanin-concentrating hormone; mesolimbic system; motivated behavior; mouse model; nerve supply; novel; obesity treatment; parent grant; prevent; public health emergency; public health relevance; receptor; recombinase; response; therapeutic target; tool

Description (provided by applicant): This is an application for competitive revision of NIH 5R01DK078056 under NOT-OD-09-058, "NIH Announces the Availability of Recovery Act Funds for Competitive Revision Applications."The ongoing epidemic of obesity in the United States represents a public health emergency that remains without specific therapy. To design specific treatments to prevent and treat obesity, we must first understand the mechanisms that regulate feeding and energy expenditure. In the parent award of this application for competitive revision, "Role of the lateral hypothalamic area in leptin action," we have defined and are studying novel LepRb-expressing neurotensin (Nts)-containing neurons in the lateral hypothalamic area (LHA). While Nts and LepRb are each expressed in numerous other locations throughout the CNS, their co-expression (or intersection, as in a Venn diagram) is restricted to these Nts/LHA LepRb neurons. The parent award for this revision application thus proposes to study the action of leptin via Nts/LHA LepRb neurons by deleting LepRb from these neurons using standard Cre/LoxP technology (i.e., Ntscre and Leprfl). Our findings to date suggest that Nts/LHA LepRb neurons modulate dopamine (DA) content in the mesolimbic DA system, and also control feeding and activity. In addition to expressing Nts, Nts/LHA LepRb neurons contain the inhibitory neurotransmitter, GABA. The wide distribution of GABA neurons throughout the brain (including in numerous LepRb populations) prevents the analysis of GABA action via Nts/LHA LepRb neurons by standard Cre/LoxP technology. Other aspects of Nts/LHA LepRb neural function are similarly not possible to study using Cre/LoxP alone. This application for competitive revision of the parent grant thus seeks to: Aim of Competitive Revision: Utilize combined Flp/Frt and Cre/LoxP approaches to activate and deactivate genes of interest in neurons that express both LepRb and Nts. (1) We will generate LeprFlp mice that express Flp recombinase in LepRb neurons. We will use LeprFlp in combination with our existing Ntscre to activate gene expression via a Cre?inducible Rosa locus transgene that we are producing. (2) We will generate NtsNeo-Cre mice, in which Flp (as from LeprFlp) removes a transcription-blocking Frt-Neo cassette to induce the expression of Cre in Nts-expressing LepRb neurons. This system will thus permit the deletion of standard conditional alleles (e.g. Vgatfl) specifically in Nts/LHA LepRb neurons. We will utilize these "intersectional" genetic technologies to more deeply explore the role of Nts/LHA LepRb neurons in energy homeostasis. The information that we will thereby obtain will provide important insight into mechanisms of leptin action and energy balance. This understanding is crucial as we seek to determine the pathogenesis of, and potential therapeutic targets for, the ongoing epidemic of obesity. Additionally, these studies will validate a novel set of tools that can genetically probe intersectional subsets of brain (or other) cells. PUBLIC HEALTH RELEVANCE: The ongoing epidemic of obesity in the United States represents a public health emergency that remains unchecked and without specific therapy. To design specific treatments to prevent and treat obesity, we must first understand the mechanisms that regulate feeding and energy expenditure in order to identify potential therapeutic targets. In this proposal, we will develop new transgenic animals to enable the more precise manipulation and study of specific subsets of neurons, including an important group of lateral hypothalamic neurons that contribute to body energy homeostasis. These studies will help us to define the function of these neurons and the potential therapeutic targets that they represent.

描述（由申请人提供）：这是根据NOT-OD-09-058“NIH宣布恢复法案资金可用于竞争性修订申请”对NIH 5 R 01 DK 078056进行竞争性修订的申请。“美国正在流行的肥胖症代表了一种公共卫生紧急情况，仍然没有具体的治疗方法。为了设计预防和治疗肥胖的具体治疗方法，我们必须首先了解调节进食和能量消耗的机制。在本申请的竞争性修订的父奖中，“外侧下丘脑区在瘦素作用中的作用”，我们已经定义并正在研究外侧下丘脑区（LHA）中新的表达LepRb的神经降压素（Nts）的神经元。虽然Nts和LepRb各自在整个CNS的许多其他位置表达，但它们的共表达（或交叉，如维恩图中所示）仅限于这些Nts/LHA LepRb神经元。因此，该修订申请的母公司奖提出通过使用标准Cre/LoxP技术从这些神经元中删除LepRb来研究瘦素经由Nts/LHA LepRb神经元的作用（即，Ntscre和Leprfl）。迄今为止，我们的研究结果表明，Nts/LHA LepRb神经元调节中脑边缘DA系统中的多巴胺（DA）含量，并控制进食和活动。除了表达Nts外，Nts/LHA LepRb神经元还含有抑制性神经递质GABA。GABA神经元在整个大脑中的广泛分布（包括在许多LepRb群体中）阻止了通过标准Cre/LoxP技术分析经由Nts/LHA LepRb神经元的GABA作用。Nts/LHA LepRb神经功能的其他方面同样无法单独使用Cre/LoxP进行研究。竞争性修订的目的：利用组合的Flp/Frt和Cre/LoxP方法来激活和失活表达LepRb和Nts的神经元中的感兴趣基因。(1)我们将产生在LepRb神经元中表达Flp重组酶的LeprFlp小鼠。我们将使用LeprFlp结合我们现有的Ntscre激活基因表达通过Cre？诱导型Rosa基因座转基因。(2)我们将产生NtsNeo-Cre小鼠，其中Flp（如来自LeprFlp）去除转录阻断Frt-Neo盒以诱导Cre在表达Nts的LepRb神经元中的表达。因此，该系统将允许在Nts/LHA LepRb神经元中特异性地缺失标准条件等位基因（例如Vgatfl）。我们将利用这些“交叉”的遗传技术，更深入地探讨Nts/LHA LepRb神经元在能量稳态中的作用。我们将由此获得的信息将提供重要的深入了解瘦素的作用和能量平衡的机制。这种理解是至关重要的，因为我们试图确定的发病机制，和潜在的治疗目标，正在进行的流行性肥胖。此外，这些研究将验证一套新的工具，可以从基因上探测脑（或其他）细胞的交叉亚群。 公共卫生相关性：美国肥胖症的持续流行代表了一种公共卫生紧急情况，这种情况仍然没有得到控制，也没有具体的治疗方法。为了设计预防和治疗肥胖的具体治疗方法，我们必须首先了解调节进食和能量消耗的机制，以确定潜在的治疗靶点。在这项提案中，我们将开发新的转基因动物，以实现更精确的操作和研究特定的神经元子集，包括一组重要的下丘脑外侧神经元，有助于身体能量稳态。这些研究将帮助我们确定这些神经元的功能以及它们所代表的潜在治疗靶点。