E-Prostanoid Receptor Subtype 2 (EP2) Regulation of Microglial Activation

E-前列腺素受体亚型 2 (EP2) 对小胶质细胞激活的调节

• 批准号: 7744758
• 负责人: Patrick J. Cimino
• 金额: $ 3.31万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-12-01 至 2012-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7744758
• 关键词: Ablation; Alzheimer' s Disease; Alzheimer' s disease model; Amyloid beta-Protein; Bone Marrow Transplantation; Brain; Candidate Disease Gene; Cell Line; Cells; Data; Deposition; Dinoprostone; Elements; Exhibits; Genes; Genetic; Goals; HIV encephalitis; Hematopoietic; Hippocampus (Brain); Human; Immune; Immune response; In Vitro; Inflammatory; Injection of therapeutic agent; Kinesis; Knockout Mice; Laboratories; Link; Lymphocyte; Maps; Mediating; Messenger RNA; Methods; Microglia; Mus; Neurodegenerative Disorders; Neurons; Nitrogen; Oxygen; Parkinson Disease; Peptides; Phagocytosis; Pharmacologic Substance; Phenotype; Physiology; Poison; Production; Prostaglandins; Protein Family; Regulation; Reporting; Role; Signal Pathway; Signal Transduction; Surveys; Testing; Transgenic Mice; Validation; Ventricular; Wild Type Mouse; aged; base; brain cell; cell type; cytokine; in vivo; member; migration; mouse model; mutant; neurotoxic; neurotoxicity; oxidative damage; paracrine; prostaglandin EP2 receptor; protein expression; receptor; response; small hairpin RNA

DESCRIPTION (provided by applicant): Activation of innate immune response in microglia is associated with the initiation or progression of several neurodegenerative diseases. Perhaps best studied in models of Alzheimer's disease (AD), innate immune activation has been shown to have both beneficial and deleterious effects on neurons. Beneficial effects are related to the clearance of nerurotoxic species of Abeta peptides, while paracrine damage to neurons results from the elaboration of a variety of toxic substances including reactive oxygen and nitrogen species. A major goal of many academic and pharmaceutical laboratories is to identify means to augment or maintain the beneficial actions of innate immune activation while suppressing paracrine neurotoxicity. Recently we demonstrated that genetic ablation of the EP2 receptor from primary mouse microglia resulted in the highly desirable dual phenotype of an increase in phagocytosis of Abeta species and complete blockade of paracrine neurotoxicity. Others have validated our findings using different methods. Taken together, these data strongly support EP2 receptor as a highly promising target for manipulating microglial innate immune response in AD and perhaps other neurodegenerative diseases. The mechanisms by which EP2-mediated signaling is related to Abeta phagocytosis and paracrine neurotoxicity are not known. Our Preliminary Data of mouse primary microglia expression identified a candidate gene that is tightly associated to EP2. We are aware of no report on the actions of this gene in any brain cells, including microglia. However, given emerging data we hypothesize that its expression and activity are mechanistically linked to EP2 signaling and that it may be a key element by which ablation of EP2 generated the highly desirable dual phenotype of enhanced Abeta phagocytosis and reduced paracrine neurotoxicity. We will test this hypothesis through the following Specific Aims: 1) Perform in vitro validation of our candidate mRNA and protein expression in wild type and EP2-/- primary mouse microglia before and after Abeta treatment. 2) Map the in vivo regional and cellular brain distribution in wild type mice and a transgenic mouse model of AD before and after following bone-marrow transplantation from either wild type or EP2-/- mice. 3) Determine the functionality of its expression in the context of the EP2-/- dual phenotype in both knockout mice and a microglial cell line using shRNA knockdown.

描述（由申请方提供）：小胶质细胞中先天免疫应答的激活与几种神经退行性疾病的发生或进展相关。也许在阿尔茨海默病（AD）模型中研究得最好，先天免疫激活已被证明对神经元既有有益的作用，也有有害的作用。有益作用与Abeta肽的神经毒性物质的清除有关，而对神经元的旁分泌损伤是由多种有毒物质（包括活性氧和氮物质）的产生引起的。许多学术和制药实验室的主要目标是确定增强或维持先天免疫激活的有益作用同时抑制旁分泌神经毒性的方法。最近，我们证明，从原代小鼠小胶质细胞的EP 2受体的基因消融导致了非常理想的双重表型的增加吞噬Abeta物种和完全阻断旁分泌神经毒性。其他人使用不同的方法验证了我们的发现。总之，这些数据强烈支持EP 2受体作为一个非常有前途的目标，在AD和其他神经退行性疾病中操纵小胶质细胞的先天免疫反应。EP 2介导的信号传导与Abeta吞噬作用和旁分泌神经毒性相关的机制尚不清楚。我们的小鼠初级小胶质细胞表达的初步数据确定了与EP 2紧密相关的候选基因。我们知道没有关于该基因在任何脑细胞（包括小胶质细胞）中作用的报道。然而，鉴于新出现的数据，我们假设它的表达和活性与EP 2信号传导机制相关，并且它可能是EP 2消融产生非常理想的增强的Abeta吞噬作用和降低的旁分泌神经毒性的双重表型的关键因素。我们将通过以下具体目的来测试该假设：1）在Abeta处理之前和之后，在野生型和EP 2-/-原代小鼠小胶质细胞中进行我们的候选mRNA和蛋白质表达的体外验证。2)绘制野生型小鼠和AD转基因小鼠模型在野生型或EP 2-/-小鼠骨髓移植前后的体内区域和细胞脑分布图。3)在敲除小鼠和小胶质细胞系中，使用shRNA敲低确定其在EP 2-/-双重表型背景下表达的功能性。