Identification of a novel GSK-3β inhibitor for Alzheimer's disease using In-Silico prediction and experiment cycling, validated in a streptozotocin-induced Alzheimer's disease mouse model.

GSK-3β has been a key target in Alzheimer's disease (AD) research for over two decades. To identify novel GSK-3β inhibitors, 333 compounds from the National Cancer Institute (NCI) database were screened using a validated ligand-based pharmacophore model with four essential features (two hydrogen bond acceptors, one hydrophobic, and one aromatic ring). After tapering screening with refined boundaries, two top compounds (NSC 275 and NSC 3198) were identified. Molecular docking and simulation studies confirmed their strong binding affinity to GSK-3β. ELISA analysis revealed that their half maximal inhibitory concentration (IC50) values were comparable to the standard GSK-3β inhibitor, CHIR99021. Subsequent in-vivo studies assessed the efficacy of these chemical entities in tested mouse model. Acute toxicity studies demonstrated no observed adverse effect level (NOAEL). Whereas behavioral tests, using the Morris water maze, the tested compounds (5 mg/kg and 10 mg/kg) exhibited cognitive improvements comparable to those of the donepezil group (1 mg/kg), an approved AD treatment. Further analysis of oxidative stress, histopathology, and immune responses in the hippocampus (CA1) indicated that the NSC 275 and NSC 3198 reversed cognitive deficits similarly to the donepezil treated group. The results suggested that combination of in-silico, in-vitro, and in-vivo approaches demonstrates the potential of NSC 275 and NSC 3198 as promising GSK-3β inhibitors for AD treatment.