Role of enteric glia in the death of neurons during gut inflammation

肠神经胶质细胞在肠道炎症期间神经元死亡中的作用

基本信息

批准号：
9269069
负责人：
BRIAN D. GULBRANSEN
金额：
$ 42.41万
依托单位：
MICHIGAN STATE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-07-15 至 2020-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9269069
关键词：
5&apos -Nucleotidase ATP Hydrolysis Ablation Acute Adenosine Affect Agonist Anti-inflammatory Astrocytes Behavior Biological Assay Biological Neural Networks Biosensing Techniques Biosensor Brain Calcium Cells Cessation of life Communication Complex Connexin 43 Cyclic AMP Data Development Disease Drug usage Enteral Enteric Nervous System Enzyme-Linked Immunosorbent Assay Event Flow Cytometry Fluorescent Probes Functional disorder Gastrointestinal Motility Glial Fibrillary Acidic Protein Gliosis Goals Human Immune Immunohistochemistry Impairment In Situ In Vitro Inflammation Inflammation Mediators Inflammatory Inflammatory Bowel Diseases Inflammatory Infiltrate Inflammatory disease of the intestine Intervention Intestines Knockout Mice Lead Link Measures Mediating Mediator of activation protein Mus Muscle Neuroglia Neuronal Dysfunction Neurons Neuropathy Neurotransmitters Outcome Pathogenesis Pathway interactions Patients Peristalsis Pharmaceutical Preparations Phase Phenotype Physiological Physiology Process Purinergic P1 Receptors Purines Receptor Activation Recruitment Activity Reflex action Regulation Resolution Role Secondary to Signal Transduction Signaling Molecule Supporting Cell Testing Therapeutic Tissues Transgenic Mice Work cell motility experimental study extracellular gastrointestinal glial activation human tissue improved in vivo in vivo Model live cell imaging motility disorder neuron loss neurotoxic new therapeutic target novel novel therapeutics public health relevance purinoceptor P2Y1 receptor response vector

项目摘要

DESCRIPTION (provided by applicant): Reflex behaviors of the intestine including peristalsis are orchestrated by the enteric nervous system (ENS); a complex neural network embedded in the gut wall. Inflammation profoundly alters ENS circuits controlling motility by promoting enteric ganglionitis; an inflammatory neuropathy characterized by the death of enteric neurons. Neuropathy is increasingly recognized as a trigger for persistent gut dysfunction in gastrointestinal (GI) motility and functional bowel disorders but the mechanisms that regulate neuropathy are not understood. This proposal investigates the role of enteric glial cells, astrocyte-like cells that surround neurons in the ENS, in the regulation of enteric neuropathy. The proposed studies will use in vivo models of GI inflammation, transgenic mice, immunohistochemistry, live-cell imaging with fluorescent probes, biosensing assays and functional tests to study neuron-glia interactions. The central hypothesis is that purinergic activation of enteric glial cells differentially regulates neuron survival depending on glial activation by ADP or adenosine. There are 2 specific aims in this proposal, each with three sub-aims. Each aim will link in vitro mechanistic studies in tissue from humans and mice with in vivo functional studies in transgenic mice. Aim 1 will test the hypothesis that glial Ca2+ responses driven by ADP cause reactive gliosis, neuron death and gut dysfunction. Specific aim 1A will test how activation of glial Ca2+ responses in GFAP:hM3Dq mice or human tissue transduced with glial- specific vectors affects the induction of reactive gliosis and neuron death. Aim 1B wil test whether glial cells directly drive neuron death by releasing neurotoxic substances or if glial driven neuron death requires immune cell recruitment. Mice with an inducible ablation of connexin-43 or MHC-II in glia will be used to specifically interfere with gliotransmitter release o immune cell recruitment, respectively. Aim 1C will test how manipulation of gliosis using the transgenic mice listed above affects in vivo and ex vivo intestinal function. Aim 2 will test the hypothesis that adenosine inhibits reactive gliosis and stimulates protective mechanisms in glia to preserve ENS function. Aim 2A will use drugs and CD73 null mice to test if activation of glial adenosine receptors is necessary and/or sufficient to reverse reactive gliosis. Aim 2B will test whether the neuroprotective actions of glial A2BR activation are mediated by altering the release of glial mediators or by decreasing the inflammatory infiltrate following in vivo inflammation in CD73 null mice. Aim 2C will use in vivo inflammation, drugs and CD73 null mice to determine how manipulation of glial adenosine signaling impacts in vivo and ex vivo assays of gut function following acute inflammation. Significance: Intestinal inflammation can drive enteric neuropathy, leading to persistent gut dysfunction in GI motility disorders. Understanding how glial mechanisms both promote, and limit enteric neuropathies is important because it could lead to the discovery of novel therapeutic targets and a common causative mechanism of neuron death in GI motility disorders, functional bowel disorders and inflammatory bowel disease.

描述（由申请人提供）：肠道的反射行为（包括蠕动）是由肠神经系统（ENS）精心策划的；炎症通过促进肠壁来深刻改变控制蠕动的 ENS 回路。神经节炎；以肠神经元死亡为特征的炎症性神经病越来越多地被认为是胃肠道（GI）运动和功能性肠病中持续性肠道功能障碍的触发因素，但调节神经病的机制尚不清楚。肠神经胶质细胞，围绕肠神经元的星形胶质细胞，在肠神经病变的调节中拟议的研究将使用胃肠道炎症的体内模型，转基因小鼠，免疫组织化学、荧光探针活细胞成像、生物传感测定和功能测试来研究神经元-神经胶质细胞的相互作用。核心假设是，肠神经胶质细胞的嘌呤能激活根据 ADP 或腺苷的神经胶质激活来差异调节神经元存活。该提案中的每个目标都有三个子目标，每个目标都将人类和小鼠组织的体外机制研究与转基因小鼠的体内功能研究联系起来。 1 将测试 ADP 驱动的神经胶质 Ca2+ 反应导致反应性神经胶质增生、神经元死亡和肠道功能障碍这一假设。具体目标 1A 将测试用神经胶质特异性载体转导的 GFAP:hM3Dq 小鼠或人体组织中神经胶质 Ca2+ 反应的激活如何影响诱导。目标 1B 将测试神经胶质细胞是否通过释放神经毒性物质直接驱动神经元死亡。驱动神经元死亡需要免疫细胞募集，在神经胶质细胞中诱导消融连接蛋白 43 或 MHC-II 将分别用于特异性干扰神经胶质递质释放或免疫细胞募集，Aim 1C 将测试如何使用转基因操纵神经胶质细胞增生。上面列出的小鼠影响体内和离体肠道功能，目的 2 将测试腺苷抑制反应性神经胶质细胞增生并刺激神经胶质细胞的保护机制以保持 ENS 功能的假设。目标 2A 将使用药物和 CD73 缺失小鼠来测试神经胶质腺苷受体的激活是否必要和/或足以逆转反应性神经胶质增生，目标 2B 将测试神经胶质 A2BR 激活的神经保护作用是否是通过改变神经胶质介质的释放来介导的。通过减少 CD73 缺失小鼠体内炎症后的炎症浸润，Aim 2C 将使用体内炎症、药物和 CD73 缺失小鼠来确定如何。神经胶质腺苷信号传导的操纵影响急性炎症后肠道功能的体内和离体测定。意义：肠道炎症可导致肠神经病变，导致胃肠道运动障碍中持续的肠道功能障碍。重要的是，它可能导致发现新的治疗靶点以及胃肠道运动障碍、功能性肠病和炎症性肠病中神经元死亡的常见致病机制。