Peripheral Degradation of Amyloid Beta-Protein

β-淀粉样蛋白的外周降解

基本信息

批准号：
7013584
负责人：
MALCOLM A LEISSRING
金额：
$ 16.64万
依托单位：
SCRIPPS FLORIDA
依托单位国家：
美国
项目类别：
财政年份：
2005
资助国家：
美国
起止时间：
2005-02-15 至 2007-10-05
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7013584
关键词：
aging amyloid proteins drug discovery /isolation drug receptors endopeptidases enzyme activity enzyme linked immunosorbent assay genetically modified animals high throughput technology laboratory mouse molecular site neprilysin neural degeneration peripheral nervous system protease inhibitor small molecule

项目摘要

DESCRIPTION (provided by applicant): Steady-state levels of the amyloid beta-protein (ABeta), which accumulates abnormally in Alzheimer's disease (AD), reflect the balance between the key processes of production, via the beta- and gamma- secretases, and proteolytic degradation, by one or more proteases. While therapies based on pharmacological blockade of the secretases have been extensively studied, very little work has examined the complimentary approach of activating or disinhibiting ABeta degrading proteases. Recent evidence shows that molecules that bind tightly to ABeta in the periphery (e.g., antibodies, gelsolin) can decrease levels of ABeta in the brain in a reaction akin to dialysis, indicating that central and peripheral pools of ABeta exist in rapid equilibrium. By extension, we hypothesize that enhancing degradation of ABeta in the periphery will also lower brain ABeta levels, an idea we call the "peripheral degradation hypothesis." To test this new hypothesis, and to identify novel drug targets and small molecule pharmacophores acting on peripheral ABeta degradation, we propose the following Aims. First, to directly test the peripheral degradation hypothesis, ABeta-degrading proteases will be overexpressed exclusively in the periphery of APP transgenic mice by using adenovirus with liver-specific promoters. Second, to identify the principal ABeta-degrading proteases in the periphery in vivo, the rate of clearance of intravenously administered AB3eta will be compared in wildtype mice and in mice lacking specific ABeta-degrading proteases. In addition, the major ABeta-degrading proteases in human serum will be identified using protease-specific inhibitors. Third, in collaboration with the Laboratory for Drug Discovery in Neurodegeneration, a high throughput ABeta-degradation assay will be performed on approximately 60,000 small molecule pharmacophores using human serum or recombinant proteases as the source of ABeta degrading activity. Collectively, the studies outlined in this proposal will evaluate--and potentially enhance--the potential of peripheral ABeta-degrading proteases as novel therapeutic targets in AD.

描述（由申请人提供）：淀粉样蛋白β-蛋白质（ABETA）的稳态水平，在阿尔茨海默氏病（AD）中累积异常，反映了通过β-和伽马分泌酶和蛋白水解的生产过程之间的平衡，以及蛋白水解的蛋白酶蛋白酶，或多个蛋白酶。虽然已经对基于药理阻滞的疗法进行了广泛的研究，但很少有工作检查了激活或抑制Abeta降解蛋白酶的免费方法。最近的证据表明，与透析类似的反应中的ABETA的分子（例如抗体，凝胶蛋白）在外围与ABETA紧密结合的分子可以降低大脑中Abeta的水平，类似于透析，表明快速平衡中存在ABETA的中央和周围池。通过扩展，我们假设增强Abeta在外围的降解也将降低脑Abeta水平，这一想法称为“外围降解假设”。为了检验这一新的假设，并确定作用于外周abeta降解的新型药物靶标和小分子药物团，我们提出了以下目的。首先，为了直接检验周围降解假设，通过将腺病毒与肝脏特异性启动子一起使用腺病毒，将仅在APP转基因小鼠的外围过度表达Abeta降解蛋白酶。其次，为了鉴定体内周围的主abeta降解蛋白酶，将在野生型小鼠和缺乏特定Abeta降解蛋白酶的小鼠中比较静脉内给予AB3ETA的清除率。此外，将使用蛋白酶特异性抑制剂鉴定人血清中主要的Abeta降解蛋白酶。第三，通过与神经退行性的药物发现实验室合作，将使用人血清或重组蛋白酶作为Abeta降解活性的来源，对大约60,000个小分子药理进行高吞吐量的Abeta降解测定法。总的来说，该提案中概述的研究将评估并有可能增强周围降解蛋白酶作为AD中新型治疗靶标的潜力。