Imidazoline-1 receptor ligands as apoptotic agents: pharmacophore modeling and virtual docking study

Comb Chem High Throughput Screen. 2013 May;16(4):298-319. doi: 10.2174/1386207311316040004.

Abstract

The group of imidazoline-1 receptors (I(1)-IR) agonists encompasses drugs are currently used in treatment of high blood pressure and hyperglycemia. The I(1)-IR protein structures have not been determined yet, but Nischarin protein that binds numerous imidazoline ligands inducing initiation of various cell-signaling cascades, including apoptosis, is identified as strong I(1)-IR candidate. In this study we examined apoptotic activity of rilmenidine (potent I(1)-IR agonist), moxonidine (moderate I(1)-IR agonist), and efaroxan (I(1)-IR partial agonist) on cancer cell line (K562) expressing Nischarin. The Nischarine domains mapping was performed by use of the Informational Spectrum Method (ISM). The 3D-Quantitative Structure-Activity Relationship (3D-QSAR) and virtual docking studies of 29 I(1)-IR ligands (agonists, partial agonists, and antagonists) were carried out on I(1)-IR receptors binding affinities. The 3D-QSAR study defined 3D-pharmacophore models for I(1)-IR agonistic and I(1)-IR antagonistic activity and created regression model for prediction of I(1)-IR activity of novel compounds. The 3D-QSAR models were applied for design and evaluation of novel I(1)-IR agonists and I(1)-IR antagonists. The most promising I(1)-IR ligands with enhanced activities than parent compounds were proposed for synthesis. The results of 3D-QSAR, ISM, and virtual docking studies were in perfect agreement and allowed precise definition of binding mode of I(1)-IR agonists (Arg 758, Arg 866, Val 981, and Glu 1057) and significantly different binding modes of I(1)-IR antagonists or partial I(1)-IR agonists. The performed theoretical study provides reliable system for evaluation of I(1)-IR agonistic and I(1)-IR antagonistic activity of novel I(1)-IR ligands, as drug candidates with anticancer activities.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / pharmacology*
  • Apoptosis / drug effects*
  • Benzofurans / chemistry
  • Benzofurans / pharmacology*
  • Cell Proliferation / drug effects
  • Dose-Response Relationship, Drug
  • Drug Screening Assays, Antitumor
  • Humans
  • Imidazoles / chemistry
  • Imidazoles / pharmacology*
  • Imidazoline Receptors / agonists*
  • Imidazoline Receptors / antagonists & inhibitors*
  • K562 Cells
  • Ligands
  • Models, Molecular
  • Molecular Docking Simulation*
  • Oxazoles / chemistry
  • Oxazoles / pharmacology*
  • Quantitative Structure-Activity Relationship
  • Rilmenidine
  • Tumor Cells, Cultured

Substances

  • Antineoplastic Agents
  • Benzofurans
  • Imidazoles
  • Imidazoline Receptors
  • Ligands
  • Oxazoles
  • imidazoline I1 receptors
  • moxonidine
  • efaroxan
  • Rilmenidine