BACE1 as a Therapeutic Target for Alzheimer's Disease

降低β水平和减少大脑中的淀粉样蛋白沉积可能对阿尔茨海默病（AD）有效。β是淀粉样斑块的主要成分，并且β(42)与AD相关。-分泌酶BACE1是启动-生成的酶，因此它（和-分泌酶）是阿尔茨海默病的主要药物靶点。p3肽（Abeta17-40/42）是γ分泌酶裂解的产物，是AD早期形成的弥漫性淀粉样斑块的主要成分。P3被认为是非淀粉样变性的，但这还没有经过严格的体内测试。我们将使用BACE1缺陷小鼠来研究这个问题，这些小鼠大脑中p3水平高，缺乏β。原则上，联合抑制BACE1和7-secretase可能比单独抑制任何一种酶更有效地降低β水平和淀粉样蛋白沉积。我们将通过分析具有复合BACE1和早老素杂合零突变的小鼠来验证这一假设。最后，BACE1作为药物靶点的价值取决于BACE1抑制是否无毒副作用，而毒副作用又取决于BACE1的生理功能。为了阐明BACE1的功能，我们将使用基因组学和蛋白质组学方法确定BACE1的途径和底物。我们的总体假设是BACE1是AD的有效药物靶点。该项目的长期目标是提供证据，证明BACE1抑制可能对阿尔茨海默病的治疗有益且毒性低。具体目标如下：1。确定体内p3是否淀粉样变性；2. 确定联合基因减少BACE1和早老素是否比单独减少任何一种酶更有效地减少β产生和淀粉样蛋白沉积；3. 利用基因组学和蛋白质组学策略鉴定BACE1的生理功能和底物。我们将使用转基因和基因敲除小鼠和培养的原代神经元作为模型系统。分析方法将包括分子（Northern， RTPCR, Western，免疫沉淀，ELISA，基因微阵列，2D-PAGE，蛋白质指纹）和细胞（免疫组织化学/光镜，免疫荧光/共聚焦显微镜）技术。这些目标将验证我们关于BACE1是有效药物靶点的总体假设，我们期望我们的结果将加强BACE1和AD -分泌酶抑制剂开发的概念基础。

Lowering Abeta levels and reducing amyloid deposition in the brain may be efficacious for Alzheimer's disease (AD). Abeta is the main component of amyloid plaques, and Abeta(42) correlates with AD. The beta-secretase, BACE1, is the enzyme that initiates Abeta generation and therefore it (and gamma-secretase) is a prime drug target for AD. The p3 peptide (Abeta17-40/42), the product alpha of gamma-secretase cleavage, is a major component of diffuse amyloid plaques that form early in AD. p3 is assumed to be non-amyloidogenic, however this has not been rigorously tested in vivo. We will study this question using BACE1 deficient mice, which have high levels of p3 and lack Abeta in the brain. In principle, the combined inhibition of both BACE1 and 7-secretase may more effectively reduce Abeta levels and amyloid deposition than inhibition of either enzyme alone. We will test this hypothesis by analyzing mice with compound BACE1 and presenilin heterozygous null mutations. Finally, the value of BACE1 as a drug target depends on whether BACE1 inhibition is free of toxic side effects, which in turn depends on the physiological functions of BACE1. To elucidate BACE1 functions, we will determine pathways and substrates of BACE1 using genomic and proteomic approaches. Our overall hypothesis is that BACE1 is a valid drug target for AD. The long-term goal of this project is to provide evidence that BACE1 inhibition is likely to be beneficial and have low toxicity for the treatment of AD. The Specific Aims are the following: 1. Determine whether p3 is amyloidogenic in vivo; 2. Determine whether combined genetic reduction of BACE1 and presenilin is more effective for decreasing Abeta production and amyloid deposition than reduction of either enzyme alone; 3. Identify BACE1 physiological functions and substrates using genomic and proteomic strategies. We will use transgenic and knockout mice and cultured primary neurons as model systems. Analytical approaches will include molecular (Northern, RTPCR, Western, immunoprecipitation, ELISA, gene microarray, 2D-PAGE, protein fingerprinting) and cellular (immunohistochemistry/light microscopy, immunofluoescence/confocal microscopy) techniques. These Aims will test our overall hypothesis that BACE1 is a valid drug target, and we expect our results will strengthen the conceptual foundation for the development of BACE1 and gamma-secretase inhibitors for AD.