Role of Dietary Polyphenols on Adult Neurogenesis and Cognition during Aging

Abstract

The formation of new neurons in adults is an important function that occurs only in specific brain regions. Adult neurogenesis plays an important role in maintaining normal brain homeostasis, replacing damaged neurons, neuronal plasticity, and cognitive functions. The generation of new neurons from Neuronal Stem Cells (NSCs) occurs throughout postnatal stages; however, the process is affected during aging. The decline of the Neuronal Progenitor Cell (NPC) population and the rate of differentiation of NPCs into neurons leads to decreased adult neurogenesis and cognitive functions during aging. Several factors that contribute to the age-associated decline of adult neurogenesis are changes in hormonal and neurotransmitter levels, formation of Amyloid β (Aβ) protein plaque aggregates, oxidative stress, and neuroinflammation. Due to anti-apoptotic, antioxidant, anti-inflammatory properties and other health benefits, plant polyphenols have been widely used to recover cognitive functions in animal models as well as in human subjects. Several studies show that intake of dietary polyphenols such as resveratrol, curcumin, grapeseed, blueberry extract, etc., induces adult neurogenesis and improves learning and memory in different animal models. The present article discussed the significance of dietary polyphenols and their effects on adult neurogenesis and cognition during aging.