BACE1 x BCHE

The development of multi-target directed ligands (MTDLs) amassed great attention to combat the multifactorial nature of Alzheimer's disease (AD). The present study showcases the synthesis of a novel series of 3-hydrazinyl indole phenacetamide derivatives aimed at addressing AD and neuroinflammation by targeting acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and β-secretase (BACE1) enzymes. The primarily in vivo anti-inflammatory screening nominated derivatives 5a-f, 5h, 5j and 5o for the initial in vitro screening against AChE. Compounds 5a-c, 5j, and 5o, exhibited the most potent inhibitory activity against AChE and BChE, were subsequently subjected to further in vivo biological evaluations. Also, 5a-c were inspected for their impact on hallmarks of AD and histopathological changes. N-phenylacetamide indole derivative bearing unsubstituted phenylhydrazinyl side chain 5a depicted the most cognitive enhancement compared to the reference standard donepezil and significantly improved spatial memory capabilities, mitigated histopathological alterations, reduced AD hallmarks, AChE, BACE1, amyloid beta (Aβ), and p-tubulin associated unit (p-Tau), and modulated oxidative and inflammatory markers, GSH and IL-1β. Moreover, in vitro BACE1 enzyme inhibition assay revealed moderate BACE1 inhibitory activity for derivatives 5a-c. Further, in silico docking studies for the most active derivatives 5a-c in AChE and BACE1 binding pockets evidenced interacting with key amino acid residues supporting their remarkable biological activity. Furthermore, molecular dynamics simulations confirmed the stability of derivative 5a within the AChE and BACE1 binding sites throughout the simulation period. Collectively, N-phenylacetamide indole derivative bearing unsubstituted phenylhydrazinyl side chain 5a represents a promising multi-target candidate, combining AChE, BChE and BACE1 inhibition and can be considered as a lead compound for further development in AD therapy.

Alzheimer's disease is age-related multifactorial neurodegenerative disease manifested by gradual loss of memory, cognitive decline and changes in personality. Due to rapid and continuous growth of its prevalence, the treatment of Alzheimer's disease calls for development of new and efficacies drugs, especially those that could be able to simultaneously act on more than one of possible targets of action. Aminoquinolines have proven to be a highly promising structural scaffold in the design of such a drug as cholinesterases and β-secretase 1 inhibitors. In this study, we synthesised twenty-two new 4-aminoquinolines with different halogen atom and its position in the terminal N-benzyl group or with a trifluoromethyl or a chlorine as C(7)-substituents on the quinoline moiety. All compounds were evaluated as multi-target-directedligands by determining their inhibition potency towards human acetylcholinesterase, butyrylcholinesterase and β-secretase 1. All of the tested derivatives were very potent inhibitors of human acetylcholinesterase and butyrylcholinesterase with inhibition constants (K_i) in the nM to low μM range. Most were estimated to be able to cross the blood-brain barrier by passive transport and were nontoxic toward cells that represented the main models of individual organs.

Argemone mexicana L. is a medicinal plant, but its impact on Alzheimer's disease (AD) is right now undetermined. We intended to investigate the in-vitro anti-AD potential of leaves and flowers of A. mexicana methanol, ethanol, and ethyl extracts and to identify multi-modal anti-AD phytochemicals by computational approaches. Molecular docking of 196 phytochemicals identified three hit phytochemicals (protoberberine, protopine, and codeine) with higher binding affinity and multi-targeting ability toward AChE, BChE, BACE-1, and GSK-3β. Further MM-GBSA assays confirmed the integrity of these phytochemicals as the hit phytochemicals. However, these phytochemicals demonstrated favorable pharmacokinetics (PK) and drugable properties having no toxicity. Molecular dynamics simulations confirmed the binding strength of the hit phytoconstituents in the active pockets of AChE, BChE, BACE-1, and GSK-3β with multi-targeting inhibitory activities. All the extracts exhibited dose-dependent antioxidant and anti-cholinesterase activities supporting the in silico results in the context of oxidative stress and cholinergic pathways. Our results offer scientific validation of the anti-AD properties of Argemone mexicana L. and identified protoberberine, protopine, and codeine that could be used for the development of multi-modal inhibitors of AChE, BChE, BACE-1, and GSK-3β to combat AD. Additional in vivo validation is recommended to ensure a thorough assessment in the present research.