In Vitro Assessment of Cholinesterase Inhibition and Neuroprotective Effects of Elaeocarpus angustifolius Blume Against Amyloid-Beta Peptide-Induced Toxicity in SH-SY5Y and BV-2 Cells.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder primarily characterized by memory impairment and cognitive decline. Pathophysiological mechanisms contributing to AD include oxidative stress, increased acetylcholinesterase activity, neuroinflammation, and the accumulation of hyperphosphorylated tau proteins and amyloid-β (Aβ) plaques in the brain. The shortcomings of existing therapeutic approaches have necessitated the exploration of alternative treatment strategies. Elaeocarpus angustifolius Blume, traditionally used for neurological disorders, has been investigated for its neuroprotective potential through its alkaloid-rich fraction. This study evaluated the acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activities of E. angustifolius alkaloid-rich fraction (EAF) and its protective effects against Aβ_1-42-induced cytotoxicity in human neuron-like SH-SY5Y cells and murine microglial BV-2 cells using the MTT assay. The results demonstrated that for AChE and BuChE, EAF showed significant inhibition with IC50 of 145.1 ± 4.782 µg/mL and 165.8 ± 1.10 µg/mL, respectively. In the MTT assay, EAF effectively mitigated Aβ_1-42-induced cytotoxicity in a dose-dependent manner, with the highest dose (100 µg/mL) restoring viability from 67.91 to 75.31% in SH-SY5Y cells and from 60.29 to 76.01% in BV-2 cells. From these results, it is apparent that EAF has anticholinesterase and neuroprotective properties. However, further research on this may help decipher underlying mechanisms before establishing EAF as an effective alternative in treating AD.