Role of polyphenols in Alzheimer’s disease

Alzheimer's disease (AD) is a complex and multifactorial neurodegenerative condition.The complex pathology of this disease includes oxidative stress, metal deposition, formation of aggregates of amyloid and tau, enhanced immune responses, and alter cholinesterase levels.Drugs targeted toward the reduction of amyloidal load have been discovered, but there is no effective pharmacological treatment for combating the disease so far.Natural products have become an important avenue for drug discovery research.Polyphenols are natural products that have been shown to be effective in the modulation of the type of neurodegenerative changes found in AD, suggesting a possible therapeutic role.This article focuses on the role of polyphenols in modulating the most important, i.e., amyloid precursor protein (APP) processing.We also provide new hypotheses on how these therapeutic molecules may modulate APP processing, prevent Ab aggregation, and favor disruption of preformed fibrils.Finally, the role of polyphenols in modulating Alzheimer's pathology is discussed.