Study on the Interactions of Two Isomer Selaginellins as Novel Small Molecule Inhibitors Targeting PTP1B by Docking and Molecular Dynamics Simulations

Abstract

Protein Tyrosine Phosphatase 1B (PTP1B) plays a key role in down-regulation of insulin and leptin signaling pathways. Therefore, development of novel inhibitors of PTP1B has becoming research focus in reducing blood sugar levels for Diabetes Mellitus and Obesity. Hence, we selected two isomer Selaginellins (1 and 2) to explain and analyze the binding mechanism of the two potential inhibitors against the PTP1B by molecule docking and molecular dynamics simulations. Firstly, the two isomers (1 and 2) and the initial ligand 19 were docked to the receptor of PTP1B by using molecular docking technology. Secondly, taken the 19 as an indicator, molecular dynamic (MD) simulations and molecular mechanics/generalized born surface area (MM/GBSA) methods were requested to assess the binding affinity and complex stability of the two chemicals towards PTP1B. Finally, we explained that the interactions of compound 1 and 2 take up the active binding site PTP1B. Simultaneously, energy decomposition analysis recognized several amino acid residues situated in substrate-binding site that might provide clues for future inhibitor exploitation towards PTP1B. In conclusion, these results may explain the reasons of differences of optical isomer biological activity and provide valuable information for developing novel inhibitors targeting PTP1B-mediated glucose transport and metabolism for Diabetes Mellitus and Obesity therapeutics.