Dietary polyphenol-derived protection against neurotoxic β-amyloid protein: from molecular to clinical.

Polyphenolic compounds derived mainly from plant products have demonstrated neuroprotective properties in a number of experimental settings. Such protective effects have often been ascribed to antioxidant capacity, but specific augmentation of other cellular defences and direct interactions with neurotoxic proteins have also been demonstrated. With an emphasis on neurodegenerative conditions, such as Alzheimer's disease, we highlight recent findings on the neuroprotection ascribed to bioactive polyphenols capable of directly interfering with the Alzheimer's disease hallmark toxic β-amyloid protein (Aβ), thereby inhibiting fibril and aggregate formation. This includes compounds such as the green tea polyphenol (-)-epigallocatechin-3-gallate (EGCG) and the phytoalexin resveratrol. Targeted studies on the biomolecular interactions between dietary polyphenolics and Aβ have not only improved our understanding of the pathogenic role of β-amyloid, but also offer fundamentally novel treatment options for Alzheimer's disease and potentially other amyloidoses.