Effects of Clioquinol on Metal-Triggered Amyloid-beta Aggregation Revisited

Abstract

Amyloid-β (Aβ) plaques are largely associated with the neuropathogenesis of Alzheimer's disease (AD). Metal ions such as Cu II and Zn II have been implicated as contributors to their formation and deposition. Metal chelators have been used to modulate metalinduced Aβ aggregation. The bidentate ligand clioqulnol (CQ) presents an effective influence on metal-involved Aβ aggregation, which has been explained through its metal chelation and is generally monitored by fluorescence and turbidity assays in vitro. The studies herein, however, suggest that the effects of CQ on metal-driven Aβ aggregation may not be visualized accurately by both assays. Subsequently, the present work demonstrates that CQ is able to chelate metal ions from metal - Aβ species and to assist, in part, in the disaggregation of Aβ aggregates, but it could not completely hinder the progression of Aβ aggregation.