Identification and investigation of hits targeting the N-methyl-D-aspartate receptor via drug repurposing: A plausible approach for anti-Alzheimer drug discovery

Abstract

The effective treatment of neurological diseases, particularly Alzheimer's disease (AD), is a significant source of frustration for drug discovery scientists. The lengthy process of drug discovery further makes this task exceedingly challenging. To enable a rapid stride in drug discovery, we focused on the drug repurposing strategy to identify new N-methyl-D-aspartate receptor (NMDAR) inhibitors from the pool of 1827 approved USFDA drugs. The high throughput virtual screening (HTVS) followed by molecular docking and molecular mechanics studies enabled us to identify two drugs, Ertugliflozin (Dock Score: −9.43 kcal/mol, MMGBSA: −104.50 kcal/mol) and Selpercatinib (Dock Score: 8.11 kcal/mol, MMGBSA: 83.62 kcal/mol), with a high affinity towards the NMDAR. The molecular dynamics analysis on these identified drugs led us to choose Ertugliflozin for its better stability as a lead for further studies. The corroboration of in silico findings led us to deduce that Ertugliflozin can inhibit NMDAR with an IC₅₀ of 613.19 nM. These results were confirmed by the anti-NMDAR ELISA-based analysis, which was further deduced via western blotting. The work is further supported by strong literature evidence that concludes the impact of antidiabetic molecules on AD progression, along with the evidence that Ertugliflozin possesses efficacy against AD with unequivocal evidence on the biological target and the mechanism. Further work, however, is required to establish this association in the in vivo or suitable model that could mimic the AD microenvironment as a part of future research.