Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States.
J Am Chem Soc. 2010 Dec 1;132(47):17015-22. doi: 10.1021/ja107552s. Epub 2010 Nov 9.
The amyloid-β (Aβ) aggregation pathway is a key target in efforts to discover therapeutics that prevent or delay the onset of Alzheimer's disease. Efforts at rational drug design, however, are hampered by uncertainties about the precise nature of the toxic aggregate. In contrast, high-throughput screening of compound libraries does not require a detailed understanding of the structure of the toxic species, and can provide an unbiased method for the discovery of small molecules that may lead to effective therapeutics. Here, we show that small molecule microarrays (SMMs) represent a particularly promising tool for identifying compounds that bind the Aβ peptide. Microarray slides with thousands of compounds immobilized on their surface were screened for binding to fluorescently labeled Aβ. Seventy-nine compounds were identified by the SMM screen, and then assayed for their ability to inhibit the Aβ-induced killing of PC12 cells. Further experiments focused on exploring the mechanism of rescue for one of these compounds: Electron microscopy and Congo red binding showed that the compound enhances fibril formation, and suggest that it may rescue cells by accelerating Aβ aggregation past an early toxic oligomer. These findings demonstrate that the SMM screen for binding to Aβ is effective at identifying compounds that reduce Aβ toxicity, and can reveal potential therapeutic leads without the biases inherent in methods that focus on inhibitors of aggregation.
淀粉样蛋白-β（Aβ）聚集途径是发现预防或延缓阿尔茨海默病发作的治疗方法的关键目标。然而，合理药物设计的努力受到关于有毒聚集体的确切性质的不确定性的阻碍。相比之下，化合物文库的高通量筛选不需要对有毒物质结构有详细的了解，并且可以为发现可能导致有效治疗的小分子提供一种无偏见的方法。在这里，我们表明小分子微阵列（SMM）代表了一种特别有前途的工具，可以识别与 Aβ 肽结合的化合物。在表面固定有数千种化合物的微阵列载玻片上筛选与荧光标记的 Aβ 结合的化合物。通过 SMM 筛选鉴定出 79 种化合物，然后测定它们抑制 Aβ 诱导的 PC12 细胞杀伤的能力。进一步的实验集中在探索其中一种化合物的拯救机制上：电子显微镜和刚果红结合表明该化合物增强了纤维形成，并表明它可能通过加速 Aβ 聚集越过早期有毒寡聚物来拯救细胞。这些发现表明，用于与 Aβ 结合的 SMM 筛选能够有效识别降低 Aβ 毒性的化合物，并且可以在没有关注聚集抑制剂的方法固有的偏见的情况下揭示潜在的治疗线索。
