"Role of CXCR2 in beta-amyloid Induced Neurodegeneration"

“CXCR2 在 β-淀粉样蛋白诱导的神经变性中的作用”

• 批准号: 7503352
• 负责人: GUO-HUANG FAN
• 金额: $ 32.04万
• 依托单位: MEHARRY MEDICAL COLLEGE
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7503352
• 关键词: Alzheimer' s Disease; Amyloid; Amyloid beta-Protein; Amyloid beta-Protein Precursor; Animal Model; Astrocytes; Behavior assessment; Brain; Brain region; Cessation of life; Clinical; Excitatory Amino Acids; Exhibits; Failure; Glutamates; Hippocampus (Brain); Human; IL8RB gene; Impairment; In Vitro; Inflammatory; Infusion procedures; Interleukin-8B Receptor; Interruption; Irritants; Knock-out; Knockout Mice; Ligands; MEKs; Mediating; Microglia; Mus; Mutant Strains Mice; N-Methylaspartate; Natural regeneration; Nerve Degeneration; Neurodegenerative Disorders; Neurofibrillary Tangles; Neuroglia; Neuronal Injury; Neurons; Numbers; Pathogenesis; Pathway interactions; Patients; Peptides; Phosphorylation; Prevention; Protein Overexpression; Recycling; Role; Signal Pathway; Signal Transduction; Testing; Therapeutic; Therapeutic Intervention; Toxic effect; Transgenic Mice; Wild Type Mouse; attenuation; base; chemokine; chemokine receptor; cytokine; desensitization; extracellular; in vivo; mutant; neuron loss; neuroprotection; neurotoxic; neurotoxicity; receptor; receptor sensitivity; research study; response; tool

Chemokines are up-regulated in the brain of Alzheimer's disease patients and are produced after amyloid-beta stimulation of glial cells.Based on these initial findings, we propose the following hypothesis: 1) some (if not all) chemokines produced by the reactive glial cells protect neurons against the toxicity of amyloid-b peptide through activation of the cognate chemokine receptors. 2) Specific signaling pathways initiated by the chemokine receptors are involved in the chemokine receptor-mediated neuroprotection. 3) Chemokine receptors in the inflamed CNS become constitutively desensitized due to the over-stimulation of the receptors by the excessive chemokines and excitatory amino acids produced by the activated astrocytes and microglial cells, thus resulting in attenuation of the chemokine receptor-mediated neuroprotection in clinical settings, such as those occuring in Alzheimer's disease. I propose the following specific aims to test these hypotheses. Aim 1. To determine whether CXCR2 is involved in the protection against amyloid-b peptide-induced neuronal death using CXCR2 knock-out mice and a selective CXCR2 antagonist in transgenic mice overexpressing human mutant human amyloid precursor protein as experimental tools. Aim 2. To determine the signaling pathways of CXCR2 involved in the receptor-mediated neuroprotection against amyloid-b peptide -induced neuronal damage. . To examine the contribution of glutamate- and chemokine-induced receptor desensitization and impairment of receptor resensitization to the failure of CXCR2 overexpression in AD to protect against neurodegeneration: Several important fundamental understandings will result from our studies, all of which have signficance for the understanding of the pathogenesis of neurodegenerative disease and its therapeutic interruption or prevention. First, we will clarify the role of the CXCR2 receptor in neuroprotection from pathways activated by b-Amyloid protein, in vitro and in vivo, utilizing complementary morphological, functional and behavioral assessments. Second, we will test the hypothesis that chemokinemediated signaling relevant for neuroprotection is counteracted by NMDA via mechanisms related to interruption of CXCR2 recycling and regeneration of receptor sensitivity to endogenous chemokines produced in excess in pathological settings, providing evidence for useful strategies for therapeutic intervention in AD and other neurodegenerative diseases.

趋化因子在阿尔茨海默病患者的大脑中上调，并在淀粉样β蛋白产生后产生 基于这些初步发现，我们提出了以下假设：1)一些(如果 不是所有的)由反应性胶质细胞产生的趋化因子保护神经元免受淀粉样蛋白B的毒性 通过激活同源趋化因子受体的多肽。2)特定的信号通路由 趋化因子受体参与趋化因子受体介导的神经保护。3)趋化因子 炎症的中枢神经系统中的受体由于过度刺激而结构性地脱敏 由激活的星形胶质细胞产生的过量趋化因子和兴奋性氨基酸引起的受体 小胶质细胞，从而导致趋化因子受体介导的临床神经保护作用减弱 环境，例如在阿尔茨海默病中发生的那些。我提出了以下具体目标来测试这些 假设。目的1.确定CXCR2是否参与了对淀粉样蛋白b肽诱导的保护作用 CXCR2基因敲除小鼠和转基因小鼠选择性CXCR2拮抗剂诱导的神经元死亡 过表达人突变人淀粉样前体蛋白作为实验工具。目标2.确定 CXCR2信号通路参与受体介导的抗淀粉样蛋白B神经保护作用 多肽诱导的神经元损伤。。检测谷氨酸和趋化因子诱导的作用 受体失敏和受体再增敏对CXCR2过表达失败的影响 预防神经退行性变的AD：几个重要的基本理解将从我们的 这些研究对于了解神经退行性变的发病机制具有重要意义。 疾病及其治疗中断或预防。首先，我们将阐明CXCR2受体在 利用互补性在体外和体内对b-淀粉样蛋白激活的通路的神经保护作用 形态、功能和行为评估。第二，我们将检验趋化运动中介的假说 NMDA通过与神经保护相关的机制来抵消与神经保护相关的信号 阻断CXCR2循环和受体对内源性趋化因子敏感性的再生 在病理环境中过量产生，为有效的治疗策略提供证据 干预AD和其他神经退行性疾病。