The effect of brain derived neurotrophic factor on presynaptic function

脑源性神经营养因子对突触前功能的影响

• 批准号: 10534078
• 负责人: Camille Wang
• 金额: $ 3.2万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10534078
• 关键词: Action Potentials; Acute; Affect; Affinity; Antidepressive Agents; Bathing; Binding; Biological; Biology; Brain; Brain-Derived Neurotrophic Factor; Calcium; Calcium Signaling; Cell Culture Techniques; Characteristics; Chelating Agents; Chronic; Clinical; Communication; Critical Thinking; Data; Development; Disease; Down-Regulation; Drug Targeting; Egtazic Acid; Environment; Event; Excitatory Synapse; Fluorescent Probes; Functional disorder; Glutamates; Goals; Growth Factor; Hippocampus (Brain); Imaging Techniques; In Vitro; Individual; Institutes; K 252a; Knockout Mice; Left; Light; Link; Major Depressive Disorder; Measures; Mental Depression; Mental disorders; Molecular; Mus; Neuraxis; Neurons; Neurotrophic Tyrosine Kinase Receptor Type 2; Noise; Optics; Pathway interactions; Pharmacology; Phosphotransferases; Physiological; Physiology; Play; Presynaptic Terminals; Prevention; Probability; Property; Proteins; Psychiatry; Publishing; Regulation; Research; Research Training; Role; Schizophrenia; Selective Serotonin Reuptake Inhibitor; Signal Pathway; Signal Transduction; Slice; Source; Stress; Synapses; Synaptic Transmission; Synaptic Vesicles; Synaptic plasticity; System; Technical Expertise; Techniques; Technology; Testing; Therapeutic; Training; Treatment Factor; Tropomyosin; Vesicle; Viral; Visualization; Work; antidepressant effect; base; collaborative environment; conditional knockout; genetic approach; genetic manipulation; improved; inhibitor; insight; neural circuit; neuropsychiatric disorder; neuropsychiatry; neurotransmission; neurotransmitter release; neurotrophic factor; novel; novel therapeutics; optical imaging; postsynaptic; presynaptic; receptor; response; skills; spatiotemporal; supportive environment; tool; trafficking

PROJECT SUMMARY Brain derived neurotrophic factor (BDNF) is a prevalent neurotrophin that modulates synaptic physiology and plasticity in the central nervous system. Multiple lines of evidence point towards its involvement in mental health disorders such as depression and schizophrenia, as well as the biological basis for an antidepressant effect. Yet despite its demonstrated involvement in neuropsychiatric diseases, very few studies have investigated how BDNF affects the presynaptic terminal, despite it being a fundamental component of neurotransmission. This is in part due to the difficulty of studying the presynapse and the lack of available technology to do so until more recently. Previously published work using viral manipulation in hippocampal slices demonstrates that BDNF acts upon the high affinity TrkB receptor at the presynapse to increase release probability, or the likelihood that a vesicle will be release in response to an action potential. With the resulting hypothesis that BDNF signaling specifically targets presynaptic function via TrkB signaling pathways, this proposal aims to investigate the molecular basis of BDNF’s effect at the presynapse. This will be done through the following: first, examining the effect of BDNF on excitatory neurotransmission (subaim 1.1). Preliminary data from subaim 1.1 show that in dissociated hippocampal cultures, release probability at excitatory synapses is increased in response to acute BDNF treatment in a manner dependent on TrkB activation. Subaim 1.2 will dissect the potential mechanisms underlying this effect through using pharmacological approaches to screen for potential downstream pathways that are involved in this effect. Because the spatiotemporal context of BDNF activity is critical in its effect, I will also use cTrkB KO hippocampal cultures to examine the spontaneous and evoked release events as a result of endogenous BDNF manipulation (subaim 1.3). Local calcium transients at synapses are strongly linked to neurotransmitter release, especially evoked release. I will thus investigate how presynaptic calcium transients are affected by exogenous BDNF (subaim 2.1), endogenous BDNF using cTrkB cultures (subaim 2.2), and whether BDNF utilizes calcium to modulate neurotransmission (subaim 2.3). The proposed studies will involve optical imaging of in vitro neuron cultures transfected or infected with fluorescent probes to study the presynase, as well as pharmacological and genetic manipulation tools to provide further mechanistic insight into findings. This research will further current understanding of the fundamental role of BDNF at the synapse, with implications for improving current therapeutics such as for antidepressants. The proposed research will be accomplished through a thoughtfully developed training plan that involves opportunities to further critical thinking skills, technical expertise, and scientific communication. Additionally, the research environment provided by the MSTP, Vanderbilt Brain Institute, and Department of Psychiatry is ideal for the proposed research and training plan, a collaborative and supportive environment, and focus on trainee development.

项目概要 脑源性神经营养因子 (BDNF) 是一种常见的神经营养因子，可调节突触生理学 和中枢神经系统的可塑性。多种证据表明它与心理有关 抑郁症和精神分裂症等健康疾病以及抗抑郁药的生物学基础 影响。然而，尽管它被证明与神经精神疾病有关，但很少有研究对其进行调查 BDNF 如何影响突触前末梢，尽管它是神经传递的基本组成部分。 这部分是由于研究突触前的困难以及缺乏可用的技术，直到 最近。先前发表的在海马切片中使用病毒操作的工作表明 BDNF 作用于突触前的高亲和力 TrkB 受体以增加释放概率，或 囊泡将响应动作电位而释放。由此得出的假设是 BDNF 信号传导 通过 TrkB 信号通路专门针对突触前功能，该提案旨在研究 BDNF 在突触前作用的分子基础。这将通过以下方式完成：首先，检查 BDNF 对兴奋性神经传递的影响（subaim 1.1）。 subaim 1.1 的初步数据表明， 分离的海马培养物，兴奋性突触的释放概率因急性刺激而增加 BDNF 治疗的方式依赖于 TrkB 激活。 Subaim 1.2将剖析潜在机制 通过使用药理学方法筛选潜在的下游途径来揭示这种效应 参与这种效应的。因为 BDNF 活动的时空背景对其影响至关重要，所以我将 还使用 cTrkB KO 海马培养物来检查由于 内源性 BDNF 操作（subaim 1.3）。突触处的局部钙瞬变与 神经递质释放，尤其是诱发释放。因此，我将研究突触前钙瞬变如何 受到外源性 BDNF (subaim 2.1)、使用 cTrkB 培养物的内源性 BDNF (subaim 2.2) 的影响，以及 BDNF 是否利用钙来调节神经传递（subaim 2.3）。拟议的研究将涉及 用荧光探针转染或感染的体外神经元培养物的光学成像以研究前联酶， 以及药理学和基因操作工具，为研究结果提供进一步的机制洞察。 这项研究将进一步加深目前对 BDNF 在突触中的基本作用的理解，并具有重要意义 用于改善当前的治疗方法，例如抗抑郁药。拟议的研究将完成 通过精心制定的培训计划，其中包括提高批判性思维技能的机会， 技术专长和科学交流。此外，MSTP提供的研究环境， 范德比尔特脑研究所和精神病学系非常适合拟议的研究和培训计划， 协作和支持的环境，并注重学员的发展。