Design of bisamide inhibitors of the TASK-1 potassium channel in silico†

Abstract

TWIK-related acid-sensitive potassium channel 1 (TASK-1) is expressed ubiquitously across various tissues and plays a significant role in neural activity and anesthetic modulation, making it a crucial target for pharmaceutical research. The high conservation of binding site residues within the TASK family, particularly between TASK-1 and TASK-3, necessitates the development of selective inhibitors for TASK-1. In this study, we utilized a combination of structure-based drug design (SBDD) and ligand-based drug design (LBDD) approaches. Initially, several bisamide-centered molecules were designed using the program MolAICal, which is recognized for its ability to generate selective inhibitors containing bisamide segments, and conducted preliminary screening via molecular docking. Subsequently, 3D-QSAR models were developed for 56 bisamide derivatives targeting TASK-1 and TASK-3, with the models exhibiting robust predictive capabilities (TASK-1: Q² = 0.61, R²_pred = 0.84; TASK-3: Q² = 0.60, R²_pred = 0.71). Using these models, the candidate molecules were subjected to activity prediction and subsequent filtering. Ultimately, molecular dynamics simulations, coupled with free energy calculations, pinpointed two bisamide-core molecules with favorable ADMET properties as potential selective inhibitors for TASK-1. Furthermore, molecular dynamics simulations revealed the critical role of the key residue Leu122 in conferring selectivity to bisamide compounds for TASK-1 channel proteins.