NEUROPROTECTIVE SIGNAL TRANSDUCTION AND ALZHEIMER'S DISEASE

神经保护信号转导与阿尔茨海默病

• 批准号: 6295319
• 负责人: MARK P MATTSON
• 金额: $ 20.18万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-01 至 1999-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6295319
• 关键词: Alzheimer's disease; adenosinetriphosphatase; amyloid proteins; biological signal transduction; enzyme activity; laboratory mouse; laboratory rat; neuroprotectants; nuclear factor kappa beta; oxidative stress; tissue /cell culture; tumor necrosis factor alpha

This proposal tests the hypothesis that tumor necrosis factors (TNFs) and secreted forms of beta-amyloid precursor protein (sAPPs) protect neurons against amyloid beta-peptide (Abeta) toxicity by a mechanism involving the transcription factor NFkappaB and induction of antioxidant enzymes. The neurotoxicity of Abeta is mediated by reactive oxygen species (ROS) and calcium, and preliminary data showed that TNFs and sAPPs can protect hippocampal neurons against Abeta toxicity and induce NFkappaB DNA binding activity. The specific aims of this project are: 1) To test the hypothesis that TNFs and sAPPs protect cultured hippocampal neurons against Abeta toxicity by inducing activation of NFkappaB. We will characterize induction of NFkappaB DNA binding activity by TNFs and sAPPs, determine whether other agents known to activate NFkappaB are neuroprotective, and employ antisense oligonucleotides (AODNs) to IkappaB (inhibitory subunit of NFkappaB) or p50 (transcription factor subunit). 2) To test the hypothesis that activation of NFkappaB by TNFs and sAPPs prevents Abeta-induced accumulation of ROS, impairment of ion-motive ATPase activities, and elevation of [Ca2+]i. Roles of specific ROS will be examined using assays of peroxides, hydroxyl radical, superoxide and protein carbonyl. 3) To test the hypothesis that activation of the NFkappaB signaling system by TNFs and sAPPs protects neurons by inducing the expression of antioxidant enzymes and the calcium-binding protein calbindin. This will be accomplished using antioxidant enzyme activity assays, RNAse protection assays and Western blot analysis. 4) To determine whether intraventricular administration of TNFs and sAPPs to adult rat protects hippocampal synaptosomes from Abeta-induced damage. NFkappaB activity, antioxidant enzyme activities and calbindin levels following infusion of TNF and sAPPs will be quantified and correlated with effects of TNFs and sAPPs on vulnerability of synaptosomes to Abeta. 5) To test the hypothesis that the NFkappaB signaling system is activated in AD brain in a regional pattern related to selective vulnerability. NFkappaB activity will be quantified in tissue from vulnerable brain regions (middle temporal gyrus, hippocampus, inferior parietal cortex) and relatively nonvulnerable brain regions (cerebellum, occipital pole) from AD brains and age-matched "control" brains. This research will identify fundamental mechanisms of neuronal injury and neuroprotection relevant to the pathogenesis of Alzheimer's disease.

该提案检验了肿瘤坏死因子 (TNF) 和 β-淀粉样前体蛋白 (sAPP) 的分泌形式可保护神经元 通过涉及的机制对抗淀粉样β-肽（Abeta）毒性 转录因子 NFkappaB 和抗氧化酶的诱导。 Abeta 的神经毒性是由活性氧 (ROS) 介导的 和钙，初步数据表明TNFs和sAPPs可以保护 海马神经元对抗 ​​Abeta 毒性并诱导 NFkappaB DNA 结合活性。 该项目的具体目标是： 1) 测试 TNF 和 sAPP 保护培养的海马神经元的假设 通过诱导 NFkappaB 的激活来对抗 Abeta 毒性。 我们将 表征 TNF 诱导 NFkappaB DNA 结合活性， sAPPs，确定是否有其他已知激活 NFkappaB 的药物 神经保护，并使用 IkappaB 的反义寡核苷酸 (AODN) （NFkappaB 的抑制亚基）或 p50（转录因子亚基）。 2) 检验 TNF 和 sAPP 激活 NFkappaB 的假设 防止 Abeta 诱导的 ROS 积累、离子动力损害 ATP 酶活性和 [Ca2+]i 升高。 特定ROS的角色将 使用过氧化物、羟自由基、超氧化物和 蛋白质羰基。 3）检验激活的假设 TNF 和 sAPP 的 NFkappaB 信号系统通过诱导 抗氧化酶和钙结合蛋白的表达 卡尔宾定。 这将通过抗氧化酶活性来实现 分析、RNAse 保护分析和蛋白质印迹分析。 4) 至 确定脑室内给予 TNF 和 sAPP 是否可以 成年大鼠保护海马突触体免受 Abeta 诱导的损伤。 NFkappaB 活性、抗氧化酶活性和钙结合蛋白水平 TNF 和 sAPP 输注后将被量化和关联 TNF 和 sAPP 对突触体对 Abeta 的脆弱性的影响。 5) 检验NFkappaB信号系统被激活的假设 AD 大脑中与选择性脆弱性相关的区域模式。 脆弱大脑组织中的 NFkappaB 活性将被量化 区域（颞中回、海马、顶下皮质） 以及相对不易受影响的大脑区域（小脑、枕极） 来自 AD 大脑和年龄匹配的“控制”大脑。 这项研究将 确定神经元损伤和神经保护的基本机制 与阿尔茨海默病的发病机制有关。