Title:Role of Polyphenols in Alleviating Alzheimer’s Disease: A Review
Volume: 30
Issue: 35
Author(s): Tharsius Raja William Raja, Veeramuthu Duraipandiyan*, Savarimuthu Ignacimuthu, Udaiyappan Janakiraman and Soosaimanickam Maria Packiam
Affiliation:
- Division of Phytochemistry and Ethnopharmacology, Entomology Research Institute, Loyola College, Chennai-
600034, Tamil Nadu, India
Keywords:
Polyphenol, Alzheimer’s disease, amyloid-β, tau protein, free radical scavenging, oxidative stress.
Abstract: Alzheimer’s Disease (AD) is a successive neurodegenerative disorder in the
aged population. Many chemicals and phytochemicals are used to treat AD. Polyphenols
which occur widely in various fruits, vegetables, beverages, and some other plant sources
are gaining importance in AD treatment. Polyphenols comprise various subcategories,
such as phenolic acids, lignans, tannins, stilbenes, hydroxybenzoic acid, hydroxycinnamic
acid, and flavonoids. These compounds, as sole entities or in combination, can be used
for treating AD because they have an abundance of antioxidants that are reported to be effective
in free radical scavenging, metal ion chelating, and anti-inflammatory activities.
Polyphenols of various plant origins have been studied, and these have been supported
by in vitro assays and in vivo studies in rodents. These molecules protect neurons against
oxidative stress and deposition of amyloid-β (Aβ) and tau proteins which play a vital role
in the pathogenesis of AD. Consumption of wine and other foods rich in polyphenols has
a beneficial effect on the neuronal signaling pathways, playing a vital role in shielding
neuronal cells from neurodegeneration. Their ability to reduce free radicals and chelate
metals are of great advantage. In this review, we highlight the various polyphenols that inhibit
neuronal damage and progression of AD while also providing a cure. Some of the
polyphenols covered are hesperidin, resveratrol, curcumin, catechin, kaempferol, and
quercetin. The mechanisms of the actions of three polyphenols are also elaborated.