ABSTRACT
Oxidative stress is considered to be a key mechanism underlying the pathophysiology of various diseases, like cancers, neurodegenerative diseases, cardiovascular diseases, neurological disorders, diabetes, and aging etc. Alzheimer’s disease (AD) is the most common cause of dementia (irreversible) and accounts for most of the dementia cases. Oxidative stress is found to enhance the aggregation of Aβ and increases tau protein phosphorylation and polymerization. Depletion of antioxidant enzymes during oxidative stress increases the risk of AD through Aβ oligomerization and aggravated memory dysfunction. It has been hypothesized that α-secretase activity/expression is negatively associated with oxidative stress, whereas β- and γ-secretase activities are positively associated with oxidative stress. Exogenous antioxidants, available in plants, are always helpful in scavenging excess reactive oxygen species and act in synergy with endogenous antioxidants. The role of antioxidant phytochemicals in prevention and management of AD is a key focus of the current research described in this review. Antioxidants have been found to attenuate Aβ-induced apoptosis, to reduce Aβ production and aggregation, inhibit tau aggregation, inhibit oxidative stress-induced DNA/RNA/lipid/protein modifications, and lipid peroxidation, etc. This chapter focus on the role of traditional medicinal plants and their antioxidant phytochemicals in the treatment of AD, along with the probable mechanism of action of selected antioxidant phytochemicals, and the future strategy for research in this area.
