Hussain_2025_Eur.J.Med.Chem_287_117327

Alzheimer's disease (AD) is marked by low neurotransmitter levels, inflammation, increased oxidative stress, and the aggregation of amyloid-beta and tau proteins. The development of hybrid compounds acting as multi-target-directed ligands (MTDLs) is a novel and contemporary approach in Alzheimer's disease therapeutics. The objective of our current research focuses on identifying compounds with balanced, even moderate inhibition potential against multiple targets associated with cholinergic deficit and neuroinflammation. Inspired by our previous study, the thiazolidinedione-thiazole-based framework has been employed to design and synthesize a series of new hybrids. The inhibitory effects of the synthesized compounds on selected enzymes were investigated by employing in-vitro methods. The synergistic inhibition of acetylcholinesterase (AChE), monoamine oxidase-B (MAO-B), beta-secretase (BACE-1), cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LOX) by compound 49 is believed to have a more potent effect in treating Alzheimer's disease. Enzyme kinetic studies and their effect on substrate-enzyme interactions of the compounds with significant inhibitory potency for AChE and MAO-B were also investigated. Central nervous system (CNS) penetration was determined using in-vitro PAMPA assay. A neurotoxicity test on neuroblastoma cell lines (SH-SY5Y) showed that the compounds were non-toxic. Compound 49 showed an excellent neuroprotective effect by significantly reducing H(2)O(2)-induced oxidative stress. Antioxidant enzymes were studied in an in-vivo experiment in the brains of male BALB/c mice. Compound 49 showed its ability to reduce the oxidative stress. Furthermore, molecular docking studies and 100 ns MD simulations performed on the AChE, MAO-B, and COX-2 ligand-protein complexes revealed stable conformations of the ligand-protein interactions throughout the simulations.