Docking, molecular dynamics, binding energy-MM-PBSA studies of naphthofuran derivatives to identify potential dual inhibitors against BACE-1 and GSK-3

BACE-1 and GSK-3 both are potential therapeutic drug targets for Alzheimer's disease. Recently, both these targets received attention for designing dual inhibitors. Till now only two scaffolds (triazinone and curcumin) derivatives have been reported as BACE-1 and GSK-3 dual inhibitors. In our previous work, we have reported first in class dual inhibitor for BACE-1 and GSK-3. In this study, we have explored other naphthofuran derivatives for their potential to inhibit BACE-1 and GSK-3 through docking, molecular dynamics, binding energy (MM-PBSA). These computational methods were performed to estimate the binding affinity of naphthofuran derivatives towards the BACE-1 and GSK-3. In the docking results, two derivatives (NS7 and NS9) showed better binding affinity as compared to previously reported inhibitors. Hydrogen bond occupancy of NS7 and NS9 generated from MD trajectories showed good interaction with the flap residues Gln73, Thr72 of BACE-1 and Arg141, Thr138 residues of GSK-3. MM-PBSA and energy decomposition per residue revealed different components of binding energy and relative importance of amino acid involved in binding. The results showed that the binding of inhibitors was majorly governed by the hydrophobic interactions and suggesting that hydrophobic interactions might be the key to design dual inhibitors for BACE1-1 and GSK-3. Distance between important pair of amino acid residues indicated that BACE-1 and GSK-3 adopt closed conformation and become inactive after ligand binding. The results suggested that naphthofuran derivatives might act as dual inhibitor against BACE-1 and GSK-3.