Discovery of Second-Generation NLRP3 Inflammasome Inhibitors: Design, Synthesis, and Biological Characterization

J Med Chem. 2019 Nov 14;62(21):9718-9731. doi: 10.1021/acs.jmedchem.9b01155. Epub 2019 Oct 31.

Abstract

NLRP3 inflammasomes have recently emerged as an attractive drug target for neurodegenerative disorders. In our continuing studies, a new chemical scaffold was designed as selective inhibitors of NLRP3 inflammasomes. Initial characterization of the lead HL16 demonstrated improved, however, nonselective inhibition on the NLRP3 inflammasome. Structure-activity relationship studies of HL16 identified a new lead, 17 (YQ128), with an IC50 of 0.30 ± 0.01 μM. Further studies from in vitro and in vivo models confirmed its selective inhibition on the NLRP3 inflammasome and its brain penetration. Furthermore, pharmacokinetic studies in rats at 20 mg/kg indicated extensive systemic clearance and tissue distribution, leading to a half-life of 6.6 h. However, the oral bioavailability is estimated to be only 10%, which may reflect limited GI permeability and possibly high first-pass effects. Collectively, these findings strongly encourage development of more potent analogues with improved pharmacokinetic properties from this new chemical scaffold.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line
  • Chemistry Techniques, Synthetic
  • Cytokines / biosynthesis
  • Cytokines / blood
  • Drug Design*
  • Inflammasomes / antagonists & inhibitors*
  • Inhibitory Concentration 50
  • Mice
  • NLR Family, Pyrin Domain-Containing 3 Protein / antagonists & inhibitors*
  • Permeability
  • Small Molecule Libraries / chemistry*
  • Small Molecule Libraries / metabolism
  • Small Molecule Libraries / pharmacokinetics
  • Small Molecule Libraries / pharmacology*
  • Structure-Activity Relationship

Substances

  • Cytokines
  • Inflammasomes
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • Small Molecule Libraries