Natural compounds targeting glial activation in Alzheimer’s disease: a review of curcumin, resveratrol, and luteolin

Abstract

Alzheimer’s disease, a neurodegenerative disease, is caused by the accumulation of amyloid-β (Aβ) protein and hyperphosphorylation of Tau protein in the brain, resulting in decreased cognitive function and memory. Neuroinflammation, which is the body’s defense mechanism in the brain, is one of the factors that can worsen the condition of Alzheimer’s patients. The activity of glial cells, such as microglia and astrocytes, causes the release of proinflammatory cytokines that can damage the neurons. However, currently available therapies can only address the symptoms of Alzheimer’s disease. Therefore, alternative strategies are needed that can be used to overcome Alzheimer’s disease, such as the use of natural compounds that have therapeutic potential. The purpose of this article is to discuss the potential of natural substances, such as curcumin, resveratrol, and luteolin, in modulating neuroinflammation. Curcumin, a compound contained in rhizome plants, has been shown to inhibit neuroinflammation by inhibiting the activation of innate immune signalling pathways and suppressing microglia activity. Resveratrol, a polyphenol in plants, has been reported to reduce neuroinflammation by modulating the Sirtuin 1 signalling pathway and polarizing microglia. Luteolin, a plant secondary metabolite belonging to the flavonoid group, is reported to be effective in reducing the production of reactive astrocytes and inhibits the p38 MAPK pathway to reduce neuroinflammation. Overall, preclinical evidence suggests that these natural substances show potential as therapeutic candidates for Alzheimer’s disease, although further clinical studies are still needed to confirm their efficacy and safety.