GLUTAMATE EXCITOTOXICITY AS A MECHANISM IN MS

谷氨酸兴奋性毒性是多发性硬化症的机制

• 批准号: 6465465
• 负责人: PETER WERNER
• 金额: $ 7.7万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-01-15 至 2004-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6465465
• 关键词: RNase protection assay; axon; calcium channel; calcium channel blockers; chemical structure function; clinical research; cytotoxicity; detoxification; disease /disorder model; experimental allergic encephalomyelitis; glutamate receptor; glutamates; human tissue; kainate; laboratory mouse; laboratory rat; multiple sclerosis; myelination; neurotoxins; oligodendroglia; pathologic process; pharmacokinetics; quinoxalines; relapse /recurrence; remission /regression; tissue /cell culture; tumor necrosis factor alpha

DESCRIPTION (adapted from applicant's abstract): Multiple sclerosis (MS) is a suspected autoimmune disease of the central nervous system characterized by infiltration of immune cells, loss of myelin, oligodendrocyte death and axonal damage. Among the mechanisms suspected in oligodendrocyte death and axonal damage are cell-cell contact and soluble factors such as TNF-alpha, reactive oxygen species, metalloproteinases and autoantibodies. Current therapeutic approaches attempt to modulate or suppress the aberrant immune reaction characteristic for MS and EAE. However, overlooked in most concepts is the fact that activated leukocytes and microglia also release glutamate in large quantities during inflammation. In an animal model of MS, experimental autoimmune encephalomyelitis (EAE), the investigators found that glutamate excitotoxicity plays a significant role in clinical impairment, axonal damage and demise of oligodendrocytes, work which introduced this novel mechanism to the MS problem. The hypothesis to be tested is that glutamate excitotoxicity is a major mechanism of damage in MS. Relevance to MS will be assured by studying MS material alongside EAE throughout. Using pharmacological agents which prevent excitotoxcity, they will test the hypothesis with the following experiments: 1. Dose-response studies with NBQX in EAE. This is to define the optimally protective dose of NBQX and lay the groundwork for 2., Treatment of relapsing-remitting EAE to investigate the long-term benefit of NBQX in EAE. 3. The role of glutamate excitotoxicity in axonal damage, assessed by immunohistochemistry and Western blotting will be addressed by treating EAE with NBQX and by co-localization of glutamate-producing immune cells and axonal damage in MS and EAE. 4. Determination of the developmental stage of oligodendrocytes protected by NBQX in EAE, and effect on remyelination using MBP-isoform-specific antibodies as well as MBP exon-2 RNAse protection assays. Developing oligodendrocytes are more vulnerable to glutamate excitotoxicity than mature cells and this may be important to the repair process following demyelination. 5. Charac-terization of the altered glutamate detoxification in both MS and EAE, assessed by immunohistochemistry, Western blotting and enzyme assays. A suspected role of TNF-alpha in these changes will also be determined in vitro (primary oligodendrocyte cultures) via glutamate uptake studies. 6. EAE experiments using Ca++-antagonists to reduce clinical impairment as well as pathological outcome will address the apparent role of voltage-gated Ca++ channels in excitotoxic damage in autoimmune demyelination. Their proposed work focuses on a new mechanism of CNS damage in MS. By studying the apparent benefit of glutamate antagonist And CA++-antagonists, they hope to take advantage of ongoing research in diseases such as stroke to find new avenues of intervention in the MS patient.

描述（改编自申请人的摘要）：多发性硬化症（MS）是一个 中枢神经系统的怀疑自身免疫性疾病，其特征是 免疫细胞的浸润，髓磷脂的丧失，少突胶质细胞和轴突 损害。在少突胶质细胞死亡和轴突中怀疑的机制中 损坏是细胞 - 细胞接触和可溶性因子，例如TNF-Alpha，反应性 氧，金属蛋白酶和自身抗体。当前的治疗性 试图调节或抑制异常免疫反应的方法 MS和EAE的特征。但是，在大多数概念中被忽视的是事实 激活的白细胞和小胶质细胞也释放谷氨酸 炎症期间的数量。在MS的动物模型中，实验 自身免疫性脑脊髓炎（EAE），研究人员发现谷氨酸 兴奋性毒性在临床障碍，轴突损伤中起着重要作用 和少突胶质细胞的消亡，将这种新型机制引入 MS问题。要检验的假设是谷氨酸兴奋性是 MS损害的主要机制。与MS有关的相关性将通过研究确保 MS材料与EAE一起。使用药理学剂 防止兴奋性毒性，他们将通过以下来检验该假设 实验：1。在EAE中使用NBQX进行剂量反应研究。这是为了定义 NBQX的最佳保护剂量，并为2奠定基础。 复发式EAE研究NBQX在EAE中的长期益处。 3。 谷氨酸兴奋性在轴突损伤中的作用，由 免疫组织化学和蛋白质印迹将通过治疗EAE来解决 与NBQX并通过共定位谷氨酸产生的免疫细胞和轴突 MS和EAE的损坏。 4。确定的发展阶段 在EAE中受NBQX保护的少突胶质细胞，并对使用雷梅尔的影响 MBP - 异型特异性抗体以及MBP Exon-2 RNase保护测定法。 发育的少突胶质细胞更容易受到谷氨酸兴奋性毒性的影响 比成熟的单元格，这对于维修过程可能很重要 脱髓鞘。 5。改变谷氨酸排毒的特性 MS和EAE，通过免疫组织化学，蛋白质印迹和酶进行评估 测定。 TNF-Alpha在这些变化中的可疑作用也将得到确定 通过谷氨酸摄取研究的体外（原发性少突胶质细胞培养物）。 6。 使用Ca ++的EAE实验 - 减少临床障碍以及 病理结果将解决电压门控CA ++的明显作用 自身免疫性脱髓鞘中兴奋性毒性损伤的通道。他们建议的工作 专注于MS中CNS损伤的新机制。通过研究明显 谷氨酸拮抗剂和CA ++的好处 - 拮抗剂，他们希望接受 正在进行的疾病研究的优势，例如中风，以找到新的途径 干预MS患者。