Kisspeptin Synaptic Input to POMC Neurons

Kisspeptin 对 POMC 神经元的突触输入

• 批准号: 8783527
• 负责人: Casey C Nestor
• 金额: $ 5.33万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-12-01 至 2015-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8783527
• 关键词: Address; Animals; Anorexia; Cachexia; Cations; Cells; Complex; Confocal Microscopy; Cues; Development; Disease; Dynorphins; Eating; Electrophysiology (science); Energy Metabolism; Family; Fasting; Feeding behaviors; Fiber; Food; Food Energy; Future; Gene Expression; Genetic; Goals; Harvest; Homeostasis; Hormones; Hour; Hypothalamic structure; Individual; Insulin; Insulin Receptor; Investigation; Ion Channel; KISS1R gene; Leptin; Light; Link; Mediating; Metabolic; Metabolic syndrome; Molecular; Molecular Biology; Mus; Neurokinin B; Neurons; Neurotransmitters; Pathway interactions; Peptides; Perikaryon; Peripheral; Physiological; Play; Pro-Opiomelanocortin; Regimen; Regulation; Reporter; Research; Reverse Transcriptase Polymerase Chain Reaction; Role; Signal Transduction; Signaling Molecule; Structure of nucleus infundibularis hypothalami; Synapses; Techniques; Testing; Therapeutic; Therapeutic Intervention; Time; Transgenic Organisms; adeno-associated viral vector; arginylphenylalaninamide; cellular targeting; design; disorder risk; feeding; innovation; kisspeptin; leptin receptor; male; mouse model; optogenetics; photoactivation; prevent; public health relevance; receptor; tool

DESCRIPTION (provided by applicant): The long-term goal of the proposed research is to understand the role of kisspeptin in the regulation of energy homeostasis through its modulation of hypothalamic anorexigenic neurons that control food intake and energy expenditure. Abnormalities in the central signaling of peripheral metabolic cues such as leptin and insulin have led to disorders in energy homeostasis such as the metabolic syndrome and anorexia-cachexia. Pro- opiomelanocortin (POMC) neurons play a critical role in energy homeostasis and mediate, at least in part, the central signaling of these two metabolic hormones. In addition, kisspeptin neurons have been shown to express leptin and insulin receptors, and kisspeptin administration directly stimulates POMC neurons. Therefore, kisspeptin neurons may play an integral role in the control of energy homeostasis through their synaptic input to POMC neurons. The central hypothesis of this proposal is that arcuate kisspeptin neurons, also known as KNDy (kisspeptin/neurokinin B/dynorphin) neurons, directly excite POMC cells in the arcuate nucleus through activation of canonical transient receptor potential (TRPC) channels, and this excitation is reduced in the fasted state. To address this hypothesis, I have designed two specific aims, which include a creative combination of transgenic and optogenetic tools in conjunction with molecular biology (aim 1) and electrophysiology (aim 2). In aim 1, I will elucidate the kisspeptin signalng components in POMC neurons of fed and food restricted POMC-EGFP male mice by dispersing and harvesting pools of POMC neurons for quantitative PCR analysis. Our lab has been in the forefront in the development and implementation of this technique, which gives us an extremely powerful tool to characterize signaling molecules (e.g., receptors and ion channels) in neurons. In aim 2, I will interrogate the functional connection between KNDy neurons and POMC neurons in the arcuate nucleus by using the innovative tool of optogenetics to selectively photoactivate KNDy neurons while simultaneously recording from arcuate POMC neurons. By using selective antagonists I will determine if the kisspeptin-induced activation of POMC neurons occurs via TRPC channels, as we have shown for kisspeptin-induced activation of other hypothalamic neurons (i.e., GnRH neurons). Together, the investigation of the gene expression and cellular pathways specific to th functional connectivity between KNDy and POMC neurons will help identify cellular targets for therapeutic interventions to counteract disorders associated with energy homeostasis.

描述（由申请人提供）：拟议研究的长期目标是了解kisspeptin通过调节控制食物摄入和能量消耗的下丘脑促性腺激素神经元在调节能量稳态中的作用。外周代谢信号（如瘦素和胰岛素）的中枢信号传导异常导致能量稳态紊乱，如代谢综合征和厌食-恶病质。前阿黑皮素（POMC）神经元在能量稳态中起关键作用，并至少部分介导这两种代谢激素的中枢信号传导。此外，kisspeptin神经元已被证明表达瘦素和胰岛素 受体，kisspeptin给药直接刺激POMC神经元。因此，kisspeptin神经元可能发挥不可或缺的作用，通过其突触输入POMC神经元的能量稳态的控制。该提议的中心假设是弓状kisspeptin神经元，也称为KNDy（kisspeptin/神经激肽B/强啡肽）神经元，通过激活典型瞬时受体电位（TRPC）通道直接兴奋弓状核中的POMC细胞，并且这种兴奋在激活后降低。 禁食状态。为了解决这个假设，我设计了两个具体的目标，其中包括转基因和光遗传学工具与分子生物学（目标1）和电生理学（目标2）的创造性组合。在目的1中，我将阐明kisspeptin信号成分的POMC神经元的喂养和食物限制的POMC-EGFP雄性小鼠的POMC神经元的分散和收获池的定量PCR分析。我们的实验室在这项技术的开发和实施方面一直走在前列，这为我们提供了一个非常强大的工具来表征信号分子（例如，受体和离子通道）。在目标2中，我将询问弓状核中KNDy神经元和POMC神经元之间的功能连接，通过使用光遗传学的创新工具来选择性地光激活KNDy神经元，同时记录弓状POMC神经元。通过使用选择性拮抗剂，我将确定Kisspeptin诱导的POMC神经元的激活是否通过TRPC通道发生，正如我们已经显示的Kisspeptin诱导的其他下丘脑神经元的激活（即， GnRH神经元）。总之，对KNDy和POMC神经元之间功能连接特异性的基因表达和细胞途径的研究将有助于确定治疗干预的细胞靶点，以抵消与能量稳态相关的疾病。