Regulation of in vitro Aβ1-40 aggregation mediated by small molecules.

It is well known that the transient and prolonged misfolding nature of amyloid-β (Aβ) makes it difficult to perform proper in vitro studies and obtain consistent results. From monomers to fibrils, the aggregated forms of Aβ are significant hallmarks in the Alzheimer's disease (AD) cascade and become the valuable targets for early diagnosis and therapy for AD. Thus, development of optimized in vitro fibrillogenic conditions to induce the desired Aβ states is essential to AD research. In this study, fifteen organic amino acid compounds (glycine, taurine, tramiprosate, and their derivatives) were employed to induce different fibrillogenic conditions for Aβ. The fibrillogenic patterns of Aβ peptides in these compounds were analyzed by thioflavin T assay and SDS-PAGE with photoinduced cross-linking of unmodified proteins protocols, then were analyzed and compared to those obtained via transmission electron microscopy and neuronal cell viability assays. Our study suggests various compounds capable of inducing different levels of in vitro Aβ1-40 fibrillogenesis, potentially useful tools in the study of Aβ for AD.