A cell-based screen for inhibitors of intracellular Abeta aggregation

描述（由申请人提供）：有一个新兴的共识，即非纤维胞内Abeta聚集物，而不是不溶性原纤维，是最有害的Abeta物种，可能在阿尔茨海默病（AD）的发病机制中发挥核心作用。因此，一种有吸引力的治疗阿尔茨海默病的方法是通过稳定细胞内的单体形式或破坏寡聚结构来选择性地降低潜在突触毒性的β聚集水平。低分子量药物是抑制β聚集的最有吸引力的治疗方法，因为许多小分子能够穿过血脑屏障（BBB）并穿过细胞膜。然而，从历史上看，蛋白质聚集一直是合成类药物分子的一个极其困难的目标，部分原因是两个相互作用的蛋白质通常覆盖的大表面积以及蛋白质之间的大而平坦的结合表面。另一个挑战是，虽然新型有机化合物在实验室中针对孤立目标进行测试时可能非常有效，但它们可能与期望目标以外的细胞成分发生交叉反应。在自然界中发现的小分子，通常被称为“天然产物”，在进化过程中通常在细胞内度过一段时间，并且不太可能以破坏细胞膜或DMA等细胞成分的方式相互作用。此外，最近有研究表明，许多天然产物在抑制多种蛋白质之间的相互作用方面非常有效。因此，我们正在探索的一个重要问题是，是否可以分离出有效抑制β聚集的天然产物或天然产物样分子，同时又能被活细胞耐受。这项研究的长期目标是鉴定细胞内β聚集的天然产物样抑制剂，这些抑制剂有可能作为治疗阿尔茨海默病的药物。为了实现这一目标，我们已经产生了一种基于细胞的检测方法，用于直接监测细胞内环境中的β折叠。这个特殊的应用程序寻求：(1)配置我们的新型基于细胞的折叠试验，用于组合小分子文库的高通量筛选；(2)从面向多样性的合成文库中分离出能够拮抗β聚集的天然产物样化合物。这些化合物将成为阿尔茨海默病治疗和阐明β折叠在介导神经毒性中的生理作用的生物学研究的先导。

DESCRIPTION (provided by applicant): There is an emerging consensus that non-fibrillar intracellular Abeta aggregates, rather than insoluble fibrils, are the most deleterious Abeta species and may play a central role in Alzheimer's disease (AD) pathogenesis. Thus, an attractive therapeutic approach to AD would be to seletively reduce the levels of potentially synaptotoxic Abeta aggregates by either stabilizing intracellular Abeta in its monomeric form or destabilizing the oligomeric structure. Low molecular weight drugs represent the most attractive therapeutics for inhibiting Abeta aggregation as many small molecules are capable of permeating the blood-brain barrier (BBB) and crossing cell membranes. Historically, however, protein aggregation has been an extremely difficult target to address with synthetic drug-like molecules, owing in part to the large surface area generally covered by two interacting proteins and to the large, flat binding surfaces between the proteins. Another challenge is that while new types of organic compounds may be extremely potent when tested against isolated targets in the laboratory, they may cross-react with cellular components other than the desired target. Small molecules found in nature, often called 'natural products', typically have spent time inside of a cell during the course of evolution and are less likely to interact in a manner that damages cellular components such as membranes or DMA. In addition, it has been shown recently that many natural products are quite effective at inhibiting a diverse array of protein-protein interactions. Thus, an important question that we are exploring is whether natural products or natural product-like molecules can be isolated that effectively inhibit Abeta aggregation and, at the same time, be tolerated by living cells. The long-term goal of this research is to identify natural product-like inhibitors of intracellular Abeta aggregation that have potential as therapeutic agents for treating AD. Towards this goal, we have generated a cell-based assay for directly monitoring Abeta folding in the intracellular environment. This particular application seeks to: (1) configure our novel cell-based folding assay for high-throughput screening of combinatorial small-molecule libraries; and (2) isolate natural product-like compounds from diversity-oriented synthesis libraries that are capable of antagonizing Abeta aggregation. Such compounds will serve as leads for AD therapy and for biological studies that illuminate the physiological role of Abeta folding in mediating neurotoxicity.