An Improved Screening Model To Identify Inhibitors Targeting Zinc-Enhanced Amyloid Aggregation

摘要

Zinc, which is abundant in senile plaques consisting mainly of fibrillar beta-amyloid (A(beta)), plays a critical role in the pathogenesis of Alzheimer's disease. Treatment with zinc chelators such as clioquinol has been used to prevent A(beta) aggregation in Alzheimer's patients; however, clioquinol produces severe side effects. A simple, easy, inexpensive, and versatile screen to identify zinc chelators for inhibition of A(beta) aggregation is currently unavailable. We thus developed a high-throughput screen that identifies zinc chelators with anti-A(beta) aggregation activity. The recombinant A(beta) peptides, aggregated on solid-phase microplates, formed A(beta)-immunopositive beta-sheet-containing structures in the presence of zinc. Formation of these A(beta) fibrils was specifically blocked by metal ion chelators. This screening model improves identification of zinc-enhanced A(beta) fibrils and anti-A(beta) aggregation mediated by zinc chelating. The convenient system could qualitatively and quantitatively assay a large sample pool for A(beta) aggregation inhibition and dissolution of A(beta) aggregates. This screen is practical, reliable, and versatile for comprehensive detection of amyloid fibrillation and identification of inhibitors of A(beta) aggregation.