Investigation of Three Flavonoids as Potent Tau Aggregation Inhibitors and In vivo Demonstration of Myricetin

Neurodegenerative disorders, including Alzheimer's disease (AD), are characterized by the formation and propagation of neurotoxic tau aggregates, which arise from the misfolding and subsequent aggregation of tau proteins into fibrillary structures. While tau-targeting agents represent a promising therapeutic strategy for the prevention and treatment of various neurodegenerative diseases, they currently constitute a limited subset of the treatments undergoing clinical trials. In this study, we report the potent anti-aggregation and filament disassembly effects of three flavonols: myricetin, quercetagetin, gossypetin. We observed remarkable nanomolar-to-low-micromolar 50% inhibitory concentrations (0.57-1.21μM) and low 50% disassembly concentrations (7.5-14μM) using tau seeds derived from AD mouse model brains. Furthermore, we validated that myricetin treatment was associated with a reduction in overall phosphorylated tau (p-Tau) burden in vivo in the 3xTg AD mouse model. Notably, these reductions were associated with enhanced performance in Y-maze assessments of spatial learning and memory, supporting further preclinical evaluation, including direct brain pharmacokinetic studies and mechanism-driven investigations relevant to tauopathy therapy.