SELECTIVE VULNERABILITY OF SPORADIC NEURODEGENERATIVE DISEASE

散发性神经退行性疾病的选择性脆弱性

• 批准号: 6098188
• 负责人: Stanley H. Appel
• 金额: $ 7.96万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-08-01 至 2003-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6098188
• 关键词: Alzheimer's disease; Xenopus oocyte; amyloid proteins; amyotrophic lateral sclerosis; calcium binding protein; calcium channel; calcium flux; cytotoxicity; neural degeneration; tissue /cell culture; voltage gated channel

The neurodegenerative diseases - Amyotrophic Lateral Sclerosis (ALS), Parkinson's disease, and Alzheimer's disease - are devastating clinical disorders that result in selective neuronal injury and death. Our general hypothesis is that increased intracellular calcium, and limited calcium buffering capacity, may be critically important in neurodegenerative cell injury. Our specific studies in ALS have documented the presence of antibodies to voltage-gated calcium channels (VGCC), which lead to increased intracellular calcium and cytotoxicity in vitro; and our studies in Alzheimer's disease have documented that beta amyloid peptide also increases intracellular calcium, albeit by a different mechanism, leading to cytoxicity in vitro. ALS IgG enhance calcium current of different neuronal VGCC (e.g. P-type channels in Purkinje cells and lipid bilayers; N-type channels in Xenopus oocytes expressing rat brain VGCC; and P-type or Q-type channels in a motor neuron cell line [VSC 4.1]). In VSC 4.1, the ALS IgG-mediated increase in calcium current leads to increased intracellular calcium and to cell death. This cell system as well as Xenopus oocytes injected with VGCC and rat brain mRNA will allow us to use calcium imaging and electrophysiological techniques to characterize the effects of ALS IgG on different VGCC and on calcium homeostasis and to examine the contribution to cytotoxicity of second messenger systems, including G proteins, protein kinases and phosphatases, and the calcium binding proteins calbindin D28K and parvalbumin. Factors mediating selective vulnerability in sporadic Alzheimer's disease are not well defined. Our recent studies document that beta amyloid leads to increased intracellular calcium and cell death of a substantia nigra cell line. Removal of extracellular calcium attenuates cytotoxicity, but VGCC antagonists have not effect. Aurintricarboxylic acid, an inhibitor of apoptosis, completely blocks cell death. This cell system will permit us to employ the same calcium imaging, electrophysiological and pharmacological techniques to define how beta amyloid leads to increased intracellular calcium, and to determine the role of increased intracellular calcium in mediating beta amyloid-induced cytoxicity and the influence of calcium binding proteins, calbindin D28K and/or parvalbumin on cell injury. Such studies should provide insight into the roles played by increasing intracellular calcium and altered calcium buffering on selective neuronal vulnerability in sporadic neurodegenerative disorders.

神经退行性疾病 - 肌萎缩侧索硬化症 (ALS)、 帕金森病和阿尔茨海默病 - 具有毁灭性的临床意义 导致选择性神经元损伤和死亡的疾病。 我们的将军 假设是细胞内钙增加，而钙有限 缓冲能力，对于神经退行性细胞可能至关重要 受伤。 我们对 ALS 的具体研究记录了以下因素的存在： 电压门控钙通道 (VGCC) 抗体，这会导致 增加细胞内钙和体外细胞毒性；和我们的研究 在阿尔茨海默病中，β淀粉样肽也 增加细胞内钙，尽管是通过不同的机制，导致 体外细胞毒性。 ALS IgG 增强不同钙电流 神经元 VGCC（例如浦肯野细胞和脂质双层中的 P 型通道； 表达大鼠脑 VGCC 的非洲爪蟾卵母细胞中的 N 型通道；和 P 型或 运动神经元细胞系中的 Q 型通道 [VSC 4.1]）。 在 VSC 4.1 中， ALS IgG 介导的钙电流增加导致 细胞内钙和细胞死亡。 该细胞系统以及 非洲爪蟾卵母细胞注射 VGCC 和大鼠脑 mRNA 将使我们能够使用 钙成像和电生理技术来表征 ALS IgG 对不同 VGCC 和钙稳态的影响 检查第二信使系统对细胞毒性的贡献， 包括 G 蛋白、蛋白激酶和磷酸酶以及钙 结合蛋白钙结合蛋白 D28K 和小清蛋白。 介导散发性阿尔茨海默病选择性脆弱性的因素 没有明确定义。 我们最近的研究表明，β 淀粉样蛋白会导致 增加细胞内钙和黑质细胞死亡 细胞系。 去除细胞外钙会减弱细胞毒性，但 VGCC拮抗剂没有作用。 金精三羧酸，一种抑制剂 细胞凋亡，完全阻止细胞死亡。 这个细胞系统将允许我们 采用相同的钙成像、电生理学和 确定 β 淀粉样蛋白如何导致增加的药理学技术 细胞内钙，并确定增加细胞内钙的作用 钙介导β淀粉样蛋白诱导的细胞毒性及其影响 钙结合蛋白、钙结合蛋白 D28K 和/或小清蛋白对细胞损伤的影响。 此类研究应该能够深入了解增加 细胞内钙和选择性神经元的钙缓冲改变 散发性神经退行性疾病的脆弱性。