Acetylcholinesterase (AChE) holds significance in Alzheimer's disease (AD), where cognitive impairment correlates with insufficient acetylcholine levels. AChE's role involves the breakdown of acetylcholine, moderating cholinergic neuron activity to prevent overstimulation and signal termination. Hence, inhibiting AChE emerges as a potential treatment avenue for AD. A library of 2500 compounds, derived from 25 traditionally used medicinal plants, was constructed using the IMPAAT database of traditional medicinal plants. The canonical SMILES of these compounds were collected and underwent virtual screening based on physicochemical properties, with subsequent determination of IC₅₀ values for the screened compounds followed by analysis using machine learning (ML). Subsequently, a molecular docking study elucidated both binding affinity and interactions between these compounds and AChE. The top three compounds, exhibiting robust binding affinities, underwent MM-GBSA analysis for molecular docking validation, succeeded by pharmacokinetics and toxicity evaluations to gauge safety and efficacy. These three compounds underwent MD simulation studies to assess protein–ligand complex conformational stability. Additionally, Density Functional Theory (DFT) was employed to ascertain HOMO, LUMO, energy gap, and molecular electrostatic potential. Among 2500 compounds, physicochemical properties-based virtual screening identified 80 with good properties, of which 32 showed promising IC₅₀ values. Molecular docking studies of these 32 compounds revealed various binding energies with AChE, with the best three compounds (CID 102267534, CID 15161648, CID 12441) selected for further analysis. MM-GBSA studies confirmed the promising binding energies of these three compounds, validating the molecular docking study. Further, the MD simulation studies have confirmed the structural and conformational stability of these three protein–ligand complexes. Finally, DFT calculations revealed favorable chemical features of these compounds. Thus, we can conclude that these three compounds (CID 102267534, CID 15161648, CID 12441) may inhibit the activity of AChE and can be useful as a treatment for Alzheimer's disease.

Microglia, the unique and motile immune cells of the central nervous system (CNS), function as a security guard in maintaining CNS homeostasis, primarily through calcium signaling. The calcium dynamics in microglia control important functions such as phagocytosis, cytokine release, and migration. Calcium dysregulation in microglia has been linked to several CNS disorders, like Alzheimer’s disease (AD), Parkinson’s disease (PD), multiple sclerosis (MS), and ischemic stroke (IS). Calcium entering through channels such as voltage-gated calcium channels (VGCCs), store-operated calcium entry (SOCE), and transient receptor potential (TRP) channels is essential for microglial activation and pro-inflammatory responses. Under pathological conditions, like the formation of amyloid-β plaques in AD, aggregation of α-synuclein in PD, and oxidative stress in MS, calcium dysregulation exacerbates neuroinflammation, mitochondrial dysfunction, and neurodegeneration. Therapeutic strategies targeting calcium signaling pathways, using calcium channel blockers and antioxidant interventions, show promise for alleviating microglial activation and slowing down disease progression. This review summarizes the underlying mechanisms of microglial calcium dysregulation and potential therapeutic benefits for restoring microglial calcium balance in CNS disorders.

Alzheimer’s disease (AD) is a progressive neurodegenerative condition that causes a substantial decline in cognitive functions and affects memory, thinking abilities, and daily behavior. The most prominent hallmark of AD pathogenesis is the formation of amyloid-β plaques, among other associated pathways such as neurofibrillary tangles, mitochondrial dysfunction, neuroinflammation, and oxidative stress. Butyrylcholinesterase (BuChE), an acetylcholine-degrading enzyme, plays a critical role in the progression of Alzheimer’s disease, particularly through its involvement in amyloid-β plaque formation. Thus, the inhibition of BuChE is considered a valuable therapeutic strategy for the management of AD. The present study aimed to identify potential bioactive chemicals from naturally occurring dietary compounds that could improve neurocognitive function and appear as a viable treatment for AD by inhibiting the function of BuChE. A small library of 44 natural dietary chemicals from a variety of dietary plants was subjected to comprehensive in silico studies, including molecular docking, molecular mechanics generalized born surface area (MM-GBSA) calculations, pharmacokinetics assessments, toxicity profiles, molecular dynamics (MD) simulation, and density functional theory (DFT) analysis. These studies revealed that CID 129886986 and CID 115269 showed stronger binding affinities with drug-likeness and no toxicity than the FDA-approved standard drug, Donepezil. Additionally, they exhibited strong structural stability with fewer fluctuations throughout the simulation, making them promising candidates for Alzheimer’s disease treatment.