Abstract
Background: A range of neurodegenerative and related aging diseases, such as Alzheimer’s disease, Parkinson’s disease, and type 2 diabetes, are linked to toxic protein aggregation. Yet the mechanisms of protein aggregation inhibition by small molecule inhibitors remain poorly understood, in part because most protein targets of aggregation assembly are partially unfolded or intrinsically disordered, which hinders detailed structural characterization of protein-inhibitor complexes and structural-based mechanistic elucidation. Methods: Herein we employed a small molecule screening approach to identify inhibitors against three prototype amyloidogenic proteins in neurodegeneration and related proteinopathies: amylin, Ab and tau. We further systematically investigated selected class of inhibitors under aerobic and anaerobic conditions to uncover a key determinant of the inhibitory activities.Results: One remarkable class of inhibitors identified from all three parallel screenings against different amyloidogenic proteins was catechol-containing compounds and redox-related quinones/anthraquinones. Further mechanistic studies determined that the redox state of the broad class of catechol-containing compounds is a key determinant of the amyloid inhibitor activities. Conclusion: Our small molecule library screening platform was able to identify a broad class of amyloid inhibitors. Redox was found to be a key factor not only regulating the inhibitory activities but also involving the mechanism of inhibition. The molecular insights we gained not only explain why a large number of catechol-containing natural compounds, often enriched in healthy diet, have anti-neurodegeneration and anti-aging activities, but also could guide the rational design of therapeutic or nutraceutical strategies to target a broad range of neurodegenerative and related aging diseases.
Author response: Small molecule proteostasis regulators that reprogram the ER to reduce extracellular protein aggregation
