The function and mechanisms of voltage-gated proton channel Hv1 in spinal cord injury

电压门控质子通道Hv1在脊髓损伤中的作用及机制

• 批准号: 10164879
• 负责人: Junfang Wu
• 金额: $ 47.42万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-05-15 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10164879
• 关键词: Acidosis; Acute; Address; Affect; Astrocytes; Attenuated; Brain; Brain Injuries; Brain Ischemia; Cell Death; Charge; Chronic; Clinical; Complex; Contusions; Coupling; Cytoplasm; Data; Development; Electrons; Failure; Financial compensation; Functional disorder; Future; Generations; Genetic; Goals; Hyperesthesia; Immune system; Impairment; In Vitro; Inflammation; Inflammatory; Injury; Interferons; Intervention; Ion Channel; Knockout Mice; Lead; Mediating; Microglia; Modeling; Molecular; Molecular Genetics; Mus; NADP; NADPH Oxidase; Neuraxis; Neuroglia; Neurologic; Neurologic Dysfunctions; Neurological outcome; Neurons; Pathologic; Pathway interactions; Phagocytes; Pharmacology; Phenotype; Process; Production; Protons; Reactive Oxygen Species; Recovery; Recovery of Function; Reporting; Research; Respiratory Burst; Rest; Role; Signal Pathway; Signal Transduction; Spinal Cord Contusions; Spinal cord injury; Testing; Therapeutic Intervention; Transgenic Mice; Up-Regulation; base; effective therapy; functional outcomes; gene therapy; genetic approach; improved; in vivo; inhibitor/antagonist; innovative technologies; insight; mouse model; neuroinflammation; neuron loss; neuroprotection; neurotoxic; new therapeutic target; novel; novel therapeutics; painful neuropathy; voltage

Project Summary Despite considerable research over the past 30 years, there is still no established effective treatment to improve recovery following spinal cord injury (SCI). In part, this reflects incomplete understanding of the complex secondary pathobiological mechanisms involved. The aim of our research is to understand the cellular and molecular mechanisms responsible for post-injury neuroinflammation in order to allow future development of novel therapies. The voltage-gated proton channel Hv1 is a newly discovered ion channel, highly expressed in resting microglia of the brain. Under pathological conditions, microglial Hv1 is required for NADPH oxidase (NOX)-dependent generation of ROS (reactive oxygen species) by providing charge compensation for exported electrons and relieving intracellular acidosis. Thus, Hv1 is a unique target for controlling multiple NOX activities and ROS production. However, neither the precise signaling mechanisms underlying this finding nor critical role of Hv1 in the pathophysiology of SCI are fully understood. Based on our preliminary data, we will test the hypothesis that microglial Hv1 functions as a key mechanism in neuroinflammation, through altered NOX2/ROS/IFN- signaling that modulates microglia-astrocyte interaction, thus affecting long-term neurological outcomes after SCI. We will use systemic or microglial Hv1 KO, microglial NOX2 KO transgenic mice and in vivo and in vitro innovatively technologies to determine the mechanisms of SCI-triggered Hv1 elevation on post-injury neuroinflammation. Aim 1 will determine the function and mechanisms of the Hv1 in neuroinflammation after SCI. Multiple quantitative assessments of microglia-mediated neuroinflammation will be combined with genetic or pharmacological intervention targeting Hv1 to test the hypothesis that SCI-induced microglial Hv1 activation mediates detrimental neuroinflammation and functional deficits through altered microglial NOX2/ROS signaling. Aim 2 will elucidate the role of microglial NOX2 in post-injury neuroinflammation. We will utilize genetic intervention to delete Hv1-dependent up-regulation of NOX2 in microglia, and evaluate the effects on microglial NOX2 coupling to Hv1 on neuroinflammation after SCI. Aim 3 will identify critical role of Hv1/NOX2-derived ROS/IFN- in SCI-chronic neuroinflammation through microglia-astrocyte interaction. Complimentary cellular, molecular, and genetic approaches will be used to test the hypothesis that Hv1/NOX2-mediated microglial ROS activates pro-inflammatory astrocytes resulting in secreting IFN that in turn reinforces microglial inflammation, thus contributes to astrocytes dysfunction and neuronal damage. Our study will be the first to implicate microglial Hv1/NOX2/ROS/IFN- signaling in the pathophysiology of SCI, leading to novel treatment approaches for SCI. Given the proposed roles for Hv1 in other inflammatory models, Hv1 signaling represents a generic mechanism relevant to other neuroinflammatory states.

项目摘要 尽管在过去30年中进行了大量研究，但仍未建立有效的治疗方法 改善脊髓损伤（SCI）后的恢复。在某种程度上，这反映了对 复杂的二级病理生物学机制涉及。我们研究的目的是了解细胞 以及负责伤害后神经炎症的分子机制，以便将来发展 新型疗法。电压门控质子通道HV1是一个新发现的离子通道，高度表达 在静止的小胶质细胞中。在病理条件下，NADPH氧化物需要小胶质细胞HV1 （NOX）依赖性的ROS（活性氧）通过提供电荷补偿 导出电子并缓解细胞内酸中毒。这是HV1是控制多个NOX的独特目标 活动和ROS生产。但是，这一发现的基本信号机制既不 HV1在SCI的病理生理学中的关键作用已充分理解。根据我们的初步数据，我们将 通过改变，测试小胶质细胞HV1作为神经炎症的关键机制的假设 NOX2/ROS/IFN-信号传导调节小胶质细胞相互作用，从而影响长期 科学后的神经结局。 我们将使用全身或小胶质的HV1 KO，小胶质细胞NOX2 KO转基因小鼠以及体内和体外 创新的技术，以确定伤害后SCI触发的HV1高程的机制 神经炎症。 AIM 1将确定HV1在神经炎症中的功能和机制 科幻之后。小胶质细胞介导的神经炎症的多次定量评估将与 针对HV1的遗传学或药理干预措施测试了SCI诱导的小胶质细胞HV1的假设 激活通过改变的小胶质细胞介导有害的神经炎症和功能缺陷 NOX2/ROS信令。 AIM 2将阐明小胶质细胞NOX2在伤害后神经炎症中的作用。 我们将利用遗传干预来删除小胶质细胞中NOX2的HV1依赖性上调，并评估 SCI后对小胶质细胞NOX2耦合对HV1的影响。 AIM 3将确定关键 HV1/NOX2衍生的ROS/IFN-在通过小胶质细胞 - 肌细胞中的Sci chronic神经炎症中的作用 相互作用。免费的细胞，分子和遗传方法将用于检验假设 HV1/NOX2介导的小胶质细胞ROS激活促炎的星形胶质细胞，导致分泌Ifn 进而增强小胶质细胞的注射，从而导致星形胶质细胞功能障碍和神经元损伤。 我们的研究将是第一个牵涉到病理生理学中的小胶质细胞HV1/NOX2/ROS/IFN-信号。 SCI，导致SCI的新型治疗方法。鉴于HV1在其他炎症中提出的作用 模型，HV1信号传导代表与其他神经炎症状态相关的通用机制。