Therapeutic Potential of Natural Chalcones Against Alzheimer's Disease: A Mechanistic Insight

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by cognitive deficits, amyloid-beta (Aβ) plaque deposition, tau hyperphosphorylation, oxidative stress, and chronic neuroinflammation. Therapeutic strategies are at present mainly symptomatic and do not modify the course of the disorder. Natural chalcones, precursors of flavonoids, are emerging as multi-target agents for neuroprotection since they have the ability to protect neurons and exert anti-inflammatory and antioxidant activities.

A systematic literature search was performed in PubMed, Scopus, Web of Science, and Google Scholar utilizing keywords that associate chalcones with Alzheimer's disease. Studies were included if they reported in silico docking, in vitro assays, or mechanistic insights on AD-related targets (AChE, BACE1, GSK-3β, NF-κB). Data extraction included information about the compound's identity, structural changes, docking scores, enzyme inhibition, oxidative stress, and cytokine modulation. The findings were synthesized both qualitatively and quantitatively, with structure-activity relationship (SAR) analysis emphasizing patterns of hydroxylation and methoxylation. These helped in the rational design of chalcone derivatives, which showed potential as multi-target agents against AD pathology.

Several chalcones exhibited potent inhibition against AChE and BACE1, besides reducing reactive oxygen species (ROS) generation and preventing the release of pro-inflammatory cytokines. These findings demonstrate their potential to mitigate cholinergic deficits and neuroinflammatory signaling. SAR studies revealed a significant enhancement in bioactivity for certain hydroxylation and methoxylation substituents. This provides insights into the rational design of improved chalcone derivatives.

Chalcones display multifunctional properties and are able to modulate several AD pathological signatures, suggesting potential application in the prevention of AD symptoms. Their therapeutic importance is emphasized by their combined ability to target cholinergic dysfunction, oxidative stress, and neuroinflammation. The SAR analysis further supports the focused development of chalcone-based derivatives with improved potency.

The present study provides insights into the mechanistic basis of the neuroprotective activity of chalcones and paves the way for subsequent preclinical evaluation. The chalconebased strategy holds promise for the development of potential drug candidates for the treatment of neurodegenerative diseases such as Alzheimer's disease by addressing the multi-target nature of this complex disease.