Tools for AD Research: Design of BACE2 Ligands

AD 研究工具：BACE2 配体的设计

• 批准号: 7021009
• 负责人: Pavel A Petukhov
• 金额: $ 21.14万
• 依托单位: UNIVERSITY OF ILLINOIS AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-01 至 2008-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7021009
• 关键词: Alzheimer' s disease; amyloid proteins; aspartic endopeptidases; bioassay; brain disorder chemotherapy; cell free system; chemical binding; chemical kinetics; chemical registry /resource; combinatorial chemistry; computational biology; computer simulation; cytotoxicity; drug discovery /isolation; enzyme inhibitors; isozymes; ligands; nanotechnology; small molecule

DESCRIPTION (provided by applicant): This R21 exploratory proposal uses an integrated, target-oriented approach in the rational development of BACE2 inhibitors - chemical tools that can be used to explore the basic biology of BACE2 and improve the selectivity of presently discovered active BACE1 inhibitors that are currently being developed as medications for Alzheimer's disease. There exists a broad consensus in the AD research community that the key to successful treatment of AD lies in the specific inhibition of BACE1. BACE1 is crucial for release of the amyloidogenic fragments that later form the extracellular neuritic amyloid plaques - one of factors in the pathogenesis of AD. Most of the known BACE1 inhibitors are relatively non-selective and target other aspartic proteases including the highly homologous BACE2. It has been shown that BACE2 may serve as an alternative alpha-secretase, another crucial enzyme that plays an important role in degradation of the amyloid precursor protein (APR), inhibition of which is highly undesirable. To better understand the role of BACE2 in human physiology and APP processing, we believe that selective inhibitors of this enzyme are needed as research tools. We hypothesize that it should be possible to design and synthesize inhibitors for BACE2 using an integrated multidisciplinary approach based on the combination of the computer-aided drug design, medicinal chemistry, and biology. Those compounds demonstrating BACE2 activity in the low nanomolar range will be screened at the whole cell level for their ability to alter APP processing. This iterative process is expected to yield several low nanomolar, lead- or drug-like selective inhibitors of BACE2. To achieve this goal, our specific aims are as follow: (1) Identify lead- and drug-like low molecular weight selective inhibitors of BACE2 using computer-aided drug design including de novo/rational drug design, virtual focused combinatorial library (vFCL) generation, and in silico screening of vFCL. To synthesize the best candidates from the de novo/rational design and vFCL approaches; (2) Assay candidate ligands for their inhibition of BACE1 and BACE2 in isolated enzyme assays. Potent, selective BACE2 inhibitors will be used for further optimization of ligand activity and selectivity through iterative molecular modeling, chemical synthesis, and biological tests; (3) For the best ligands, explore their effects on APP processing in cell-based assays. Prioritize inhibitors on the basis of activity, cytotoxicity, and resultant selectivity indices.

描述（由申请人提供）：该R21探索性提案在BACE 2抑制剂的合理开发中使用了一种综合的、以靶向为导向的方法-化学工具，可用于探索BACE 2的基础生物学，并提高目前发现的活性BACE 1抑制剂的选择性，这些抑制剂目前正被开发为阿尔茨海默病的药物。AD研究界存在广泛的共识，即成功治疗AD的关键在于特异性抑制BACE 1。BACE 1对于淀粉样蛋白生成片段的释放至关重要，所述淀粉样蛋白生成片段随后形成细胞外神经炎淀粉样蛋白斑块-AD发病机制中的因素之一。大多数已知的BACE 1抑制剂是相对非选择性的，并且靶向其他天冬氨酸蛋白酶，包括高度同源的BACE 2。已经显示BACE 2可以充当替代的α-分泌酶，这是在淀粉样前体蛋白（APR）的降解中起重要作用的另一种关键酶，其抑制是非常不期望的。为了更好地了解BACE 2在人体生理学和APP加工中的作用，我们认为需要这种酶的选择性抑制剂作为研究工具。我们假设，它应该是可能的设计和合成BACE 2的抑制剂，使用一个综合的多学科方法的基础上结合的计算机辅助药物设计，药物化学和生物学。将在全细胞水平筛选在低纳摩尔范围内显示BACE 2活性的那些化合物，以确定其改变APP加工的能力。这种迭代过程预计将产生几种低纳摩尔，铅或药物样的BACE 2选择性抑制剂。为了实现这一目标，我们的具体目标如下：（1）使用计算机辅助药物设计，包括从头/合理药物设计，虚拟聚焦组合库（vFCL）生成和vFCL的计算机筛选，鉴定先导和药物样低分子量BACE 2选择性抑制剂。从从头/合理设计和vFCL方法合成最佳候选物;（2）在分离的酶测定中测定候选配体对BACE 1和BACE 2的抑制。有效的、选择性的BACE 2抑制剂将用于通过迭代分子建模、化学合成和生物学测试进一步优化配体活性和选择性;（3）对于最佳配体，探索它们在基于细胞的测定中对APP加工的影响。根据活性、细胞毒性和产生的选择性指数对抑制剂进行优先排序。