A novel, broad-spectrum inhibitor of enterovirus replication that targets host cell factor phosphatidylinositol 4-kinase IIIβ

Antimicrob Agents Chemother. 2013 Oct;57(10):4971-81. doi: 10.1128/AAC.01175-13. Epub 2013 Jul 29.

Abstract

Despite their high clinical and socioeconomic impacts, there is currently no approved antiviral therapy for the prophylaxis or treatment of enterovirus infections. Here we report on a novel inhibitor of enterovirus replication, compound 1, 2-fluoro-4-(2-methyl-8-(3-(methylsulfonyl)benzylamino)imidazo[1,2-a]pyrazin-3-yl)phenol. This compound exhibited a broad spectrum of antiviral activity, as it inhibited all tested species of enteroviruses and rhinoviruses, with 50% effective concentrations ranging between 4 and 71 nM. After a lengthy resistance selection process, coxsackievirus mutants resistant to compound 1 were isolated that carried substitutions in their 3A protein. Remarkably, the same substitutions were recently shown to provide resistance to inhibitors of phosphatidylinositol 4-kinase IIIβ (PI4KIIIβ), a lipid kinase that is essential for enterovirus replication, suggesting that compound 1 may also target this host factor. Accordingly, compound 1 directly inhibited PI4KIIIβ in an in vitro kinase activity assay. Furthermore, the compound strongly reduced the PI 4-phosphate levels of the Golgi complex in cells. Rescue of coxsackievirus replication in the presence of compound 1 by a mutant PI4KIIIβ carrying a substitution in its ATP-binding pocket revealed that the compound directly binds the kinase at this site. Finally, we determined that an analogue of compound 1, 3-(3-fluoro-4-methoxyphenyl)-2-methyl-N-(pyridin-4-ylmethyl)imidazo[1,2-a]pyrazin-8-amine, is well tolerated in mice and has a dose-dependent protective activity in a coxsackievirus serotype B4-induced pancreatitis model.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 1-Phosphatidylinositol 4-Kinase / metabolism*
  • Animals
  • Antiviral Agents / pharmacology*
  • Antiviral Agents / therapeutic use*
  • Enterovirus / drug effects*
  • Enterovirus / metabolism*
  • Enterovirus / pathogenicity
  • Enzyme Activation / drug effects
  • Fluorescent Antibody Technique
  • HeLa Cells
  • Humans
  • Male
  • Mice
  • Molecular Structure
  • Pancreatitis / drug therapy
  • Pancreatitis / metabolism
  • Virus Replication / drug effects

Substances

  • Antiviral Agents
  • 1-Phosphatidylinositol 4-Kinase