Design, synthesis and biological activities of benzo[d]imidazo[1,2-a]imidazole derivatives as TRPM2-specfic inhibitors

Eur J Med Chem. 2021 Dec 5:225:113750. doi: 10.1016/j.ejmech.2021.113750. Epub 2021 Aug 14.

Abstract

Transient receptor potential melastatin 2 (TRPM2) channel is associated with ischemia/reperfusion injury, inflammation, cancer and neurodegenerative diseases. However, the lack of specific inhibitors impedes the development of TRPM2 targeted therapeutic agents. To develop a selective TRPM2 inhibitor, three-dimensional similarity-based screening strategy was employed using the energy-minimized conformation of non-selective TRPM2 inhibitor 2-APB as the query structure, which resulted in the discovery of a novel tricyclic TRPM2 inhibitor Z-4 with benzo[d]imidazo[1,2-a]imidazole skeleton. A series of Z-4 derivatives were subsequently synthesized and evaluated using calcium imaging and electrophysiology approaches. Among them, preferred compounds ZA10 and ZA18 inhibited the TRPM2 channel with micromolar half-maximal inhibitory concentration values and exhibited TRPM2 selectivity over the TRPM8 channel, TRPV1 channel, InsP3 receptor and Orai channel. The analysis of structure-activity relationship provides valuable insights for further development of selective TRPM2 inhibitors. Neuroprotection assay showed that ZA10 and ZA18 could effectively reduce the mortality of SH-SY5Y cells induced by H2O2. These findings enrich the structure types of existing TRPM2 inhibitors and might provide a new tool for the study of TRPM2 function in Reactive oxygen species (ROS) -related diseases.

Keywords: 2-APB; Inhibitors; SAR; Transient receptor potential melastatin 2 (TRPM2) channel; benzo[d]imidazo[1,2-a]imidazole.

MeSH terms

  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Dose-Response Relationship, Drug
  • Drug Design*
  • HEK293 Cells
  • Humans
  • Hydrogen Peroxide / antagonists & inhibitors
  • Hydrogen Peroxide / pharmacology
  • Imidazoles / chemical synthesis
  • Imidazoles / chemistry
  • Imidazoles / pharmacology*
  • Molecular Structure
  • Neuroprotective Agents / chemical synthesis
  • Neuroprotective Agents / chemistry
  • Neuroprotective Agents / pharmacology*
  • Structure-Activity Relationship
  • TRPM Cation Channels / antagonists & inhibitors*
  • TRPM Cation Channels / metabolism

Substances

  • Imidazoles
  • Neuroprotective Agents
  • TRPM Cation Channels
  • TRPM2 protein, human
  • imidazole
  • Hydrogen Peroxide