Identifying GSK-3 beta kinase inhibitors of Alzheimer's disease: Virtual screening, enzyme, and cell assays

摘要

Glycogen synthase kinase 3 beta (GSK-3 beta) is widely known as a critical target protein for treating Alzheimer's disease (AD). We utilized virtual screening to search databases for compounds with the potential to be used in drugs targeting GSK-3 beta kinase, and kinase as well as cell assays to investigate top-scored, selected compounds. Virtual screening of >1.1 million compounds in the ZINC and in-house databases was conducted using an optimized computational protocol in the docking program GOLD. Of the top-ranked compounds, 16 underwent a luminescent kinase assay and a cell assay using HEK293 cells expressing DsRed-tagged Delta K280 in the repeat domain of tau (tauRD). The compounds VB-003 (a potent GSK-3 beta inhibitor) and VB-008 (AM404, an anandamide transport inhibitor), with determined IC50 values of 0.25 and 5.4 mu M, respectively, were identified as reducing tau aggregation. Both compounds increased expression of phospho-GSK-3 beta (Ser9) and reduced endogenous tau phosphorylation at the sites of Ser202, Thr231, and Ser396. In the Delta K280 tau(RD)-DsRed SH-SY5Y cells, VB-008, but not VB-003, enhanced HSPB1 and GRP78 expression, increased Delta K280 tau(RD)-DsRed solubility, and promoted neurite outgrowth. Thus VB-008 performed best to the end of the present study. The identified compound VB-008 may guide the identification and synthesis of potential inhibitors analogous to this compound. (C) 2016 Elsevier B.V. All rights reserved.