PATHOGENESIS OF PHOSPHOLIPASES A2 IN AD

AD 中磷脂酶 A2 的发病机制

• 批准号: 8530658
• 负责人: GRACE Y SUN
• 金额: $ 3.1万
• 依托单位: UNIVERSITY OF MISSOURI-COLUMBIA
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至 2014-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8530658
• 关键词: Age; Agonist; Alzheimer' s Disease; Amyloid; Apoptotic; Arachidonic Acids; Astrocytes; Brain; Cell membrane; Cell model; Cell physiology; Cells; Coculture Techniques; Collaborations; Complementary DNA; Consult; Cytokine Activation; Cytokine Receptors; Cytoplasm; DNA Sequence Rearrangement; Data; Detection; Development; Disease; Disease Progression; Enzymes; Event; Generations; Glutamate Receptor; Glutamates; Goals; Guanosine Triphosphate; Hippocampus (Brain); Human; Impairment; In Vitro; Indiana; Inflammation; Inflammatory; Inflammatory Response; Lead; Link; Lipid Peroxidation; Lipids; Maintenance; Mediating; Membrane; Membrane Proteins; Memory Loss; Microarray Analysis; Microglia; Molecular Biology Techniques; Mus; N-Methylaspartate; NADPH Oxidase; Neuroglia; Neurons; Nitrogen; Nucleotides; Oxidative Stress; Oxygen; P2Y2 receptor; Pathogenesis; Pathway interactions; Peptides; Pharmacotherapy; Phospholipase A2; Phosphorylation; Phosphotransferases; Play; Production; Protein Kinase; Proteins; Rattus; Receptor Signaling; Regulation; Relative (related person); Research Personnel; Role; Sampling; Signal Pathway; Signal Transduction; Slice; Small Interfering RNA; Staging; Statistical Data Interpretation; Synaptic plasticity; Testing; The Sun; Time; Transfection; Transgenic Animals; Transgenic Mice; aspartate receptor; brain cell; brain tissue; cognitive function; cytokine; in vivo Model; inflammatory marker; insight; laser capture microdissection; lipid mediator; mRNA Expression; methyl(arginyl)-lysyl-prolyl-tryptophyl-tert-leucyl-leucine; migration; mouse model; mutant; neuroinflammation; neuron apoptosis; neurotoxic; novel; nucleotide receptor; oxidative damage; peroxidation; prenylation; programs; protein expression; protein function; receptor function; response; tissue preparation

There is strong support for the hypothesis that folding of p-amyloid (AP) peptide into a neurotoxic, oligomeric form is associated with increased oxidative stress that constitutes early events in the neuronal impairment and glial cell-mediated inflammation seen in Alzheimer's disease (AD). Phospholipases A2 (PLA2), including cytosolic cPLA2 and inflammatory secretory sPLA2-IIA, are important enzymes for the production of lipid mediators and the maintenance of membrane integrity. Although these enzymes have been implicated in other diseases, their roles in the pathogenesis of AD have not been explored sufficiently. Our recent studies have obtained novel data indicating that oligomeric Ap42 treatment of neurons enhances ROS production through NADPH oxidase and increases cPLA2 activity through intracellular kinase activation, resulting in membrane peroxidation and alterations in membrane protein function. Other new data show that sPLA2-IIA mRNA and protein expression are elevated in AD brain compared to age-matched controls. The overall goal of this project is to understand mechanisms whereby A|3, NADPH oxidase, cPLA2 and sPLA2-IIA collectively contribute to impairment of neuronal function and induction of glial-cell mediated inflammation, using accepted and novel in vitro and in vivo models of AD.Aim 1tests the hypothesis that Ap-induced cPLA2 and NADPH oxidase activation in neurons serves to modulate N-methyl-D-aspartic acid (NMDA) receptor function and induce neuronal apoptosis. Aim 2 investigates the significance and relevance to AD pathogenesis of the novel preliminary data indicating that sPLA2-IIA is up-regulated in AD and tests the hypothesis that increases in sPLA2-IIA expression caused by oligomeric Ap42 and NADPH oxidase-dependent ROS generation modulate inflammatory responses in glial cells and cause neuronal apoptosis. We will test the hypothesis that NADPH oxidase and cPLA2 up-regulate sPLA2-IIA expression and modulate inflammatory responses in glial cells, thus linking oxidative pathways to neuroinflammation. Proposed studies to evaluate novel roles for PLA2s in neuronal and glial cell functions associated with AD will evaluate responses in primary neurons and astrocytesfrom the TgCRNDS mouse model of AD, NT-2 cells over-expressing the Swedish/Indiana mutant of APP, human AD and non-demented (ND) brain tissue, and brain slices from transgenic mouse models, including TgCRNDS and TgCRNDS x sPLA2-IIA, and mice lacking cPLA2 and gp91phox, a NADPH oxidase subunit. Together, these studies will provide new information about the roles of neuronal cPLA2 in enhancing oxidative stress and impairing glutamatergic signaling in the early stages of AD, and the role of sPLA2-IIA in inflammatory responses in glial cells, information that we believe can lead to novel pharmacotherapies to retard disease progression.

对假设的假设有很大的支持，即将p-淀粉样蛋白（AP）肽折叠为神经毒性，寡聚 形式与构成神经元障碍早期事件的氧化应激增加有关 以及神经胶质细胞介导的炎症（AD）。磷脂酶A2（PLA2），包括 胞质CPLA2和炎症分泌Spla2-IIA是生产脂质的重要酶 介体和膜完整性的维护。尽管这些酶已与 其他疾病，尚未充分探索它们在AD发病机理中的作用。我们最近的研究 已经获得了新的数据，表明寡聚AP42神经元的治疗可增强ROS的产生 通过NADPH氧化酶，通过细胞内激酶激活增加CPLA2活性，导致 膜过氧化和膜蛋白功能的改变。其他新数据显示SPLA2-IIA 与年龄匹配的对照相比，AD脑中的mRNA和蛋白质表达升高。总体 该项目的目标是了解| 3，NADPH氧化酶，CPLA2和SPLA2-IIA的机制 共同有助于神经元功能损害和诱导胶质细胞介导 炎症，使用AD的体外和新颖的体外和体内模型。 神经元中AP诱导的CPLA2和NADPH氧化酶活性可调节N-甲基-D-天冬氨酸 酸（NMDA）受体功能并诱导神经元凋亡。 AIM 2调查了重要性和 与新型初步数据的AD发病机理有关，表明SPLA2-IIA在AD中被上调 并检验了以下假设，即寡聚AP42和NADPH引起的SPLA2-IIA表达增加 氧化酶依赖性ROS产生调节神经胶质细胞的炎症反应并引起神经元 凋亡。我们将测试NADPH氧化酶和CPLA2上调SPLA2-IIA表达的假设 并调节神经胶质细胞的炎症反应，从而将氧化途径与神经炎症联系起来。 拟议的研究评估PLA2在与AD相关的神经元和神经胶质细胞功能中的新作用 将从AD的TGCRNDS小鼠模型NT-2评估原发性神经元和星形胶质细胞的反应 过表达瑞典/印第安纳州APP，人AD和非痴呆（ND）脑组织的细胞， 来自转基因小鼠模型的大脑切片，包括TGCRND和TGCRNDS X SPLA2-IIA，以及小鼠 缺少CPLA2和GP91Phox，一种NADPH氧化酶亚基。这些研究将共同​​提供新的 有关神经元CPLA2在增强氧化应激和损害谷氨酸能的作用的信息 在AD的早期阶段发出信号，以及SPLA2-IIA在神经胶质细胞中炎症反应中的作用， 我们认为可以导致新型药物疗法以延迟疾病进展的信息。