Abstract
Alzheimer’s disease (AD) is a commonly reported neurodegenerative disorder associated
with dementia and cognitive impairment. The pathophysiology of AD comprises Aβ, hyperphosphorylated
tau protein formation, abrupt cholinergic cascade, oxidative stress, neuronal apoptosis, and neuroinflammation.
Recent findings have established the profound role of immunological dysfunction and
microglial activation in the pathogenesis of AD. Microglial activation is a multifactorial cascade encompassing
various signalling molecules and pathways such as Nrf2/NLRP3/NF-kB/p38 MAPKs/
GSK-3β. Additionally, deposited Aβ or tau protein triggers microglial activation and accelerates its
pathogenesis. Currently, the FDA-approved therapeutic regimens are based on the modulation of the
cholinergic system, and recently, one more drug, aducanumab, has been approved by the FDA. On the
one hand, these drugs only offer symptomatic relief and not a cure for AD. Additionally, no targetedbased
microglial medicines are available for treating and managing AD. On the other hand, various
natural products have been explored for the possible anti-Alzheimer effect via targeting microglial activation
or different targets of microglial activation. Therefore, the present review focuses on exploring
the mechanism and associated signalling related to microglial activation and a detailed description of
various natural products that have previously been reported with anti-Alzheimer’s effect via mitigation
of microglial activation. Additionally, we have discussed the various patents and clinical trials related
to managing and treating AD.
Graphical Abstract
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