Inhibition of NLRP3 Inflammasome Prevents LPS-Induced Inflammatory Hyperalgesia in Mice: Contribution of NF-κB, Caspase-1/11, ASC, NOX, and NOS Isoforms

Inflammation. 2017 Apr;40(2):366-386. doi: 10.1007/s10753-016-0483-3.

Abstract

The nucleotide-binding domain and leucine-rich repeat protein 3 (NLRP3), an intracellular signaling molecule that senses many environmental- and pathogen/host-derived factors, has been implicated in the pathogenesis of several diseases associated with inflammation. It has been suggested that NLRP3 inflammasome inhibitors may have a therapeutic potential in the treatment of NLRP3-related inflammatory diseases. The aim of this study was to determine whether inhibition of NLRP3 inflammasome prevents inflammatory hyperalgesia induced by lipopolysaccharide (LPS) in mice as well as changes in expression/activity of nuclear factor κB (NF-κB), caspase-1/11, nicotinamide adenine dinucleotide phosphate oxidase (NOX), and endothelial/neuronal/inducible nitric oxide synthase (eNOS/nNOS/iNOS) that may regulate NLRP3/apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC)/pro-caspase-1 inflammasome formation and activity by using a selective NLRP3 inflammasome inhibitor, MCC950. Male mice received saline (10 ml/kg; i.p.), LPS (10 mg/kg; i.p.), and/or MCC950 (3 mg/kg; i.p.). Reaction time to thermal stimuli within 1 min was evaluated after 6 h. The mice were killed and the brains, hearts, and lungs were collected for measurement of NF-κB, caspase-1, caspase-11, NLRP3, ASC, NOX subunits (gp91phox; NOX2), and p47phox; NOXO2), nitrotyrosine, eNOS, nNOS, iNOS, and β-actin protein expression, NOS activity, and interleukin (IL)-1β levels. LPS-induced hyperalgesia was associated with a decrease in eNOS, nNOS, and iNOS protein expression and activity as well as an increase in expression of NF-κB p65, caspase-1 p20, caspase-11 p20, NLRP3, ASC, gp91phox, p47phox, and nitrotyrosine proteins in addition to elevated IL-1β levels. The LPS-induced changes were prevented by MCC950. The results suggest that inhibition of NLRP3/ASC/pro-caspase-1 inflammasome formation and activity prevents inflammatory hyperalgesia induced by LPS in mice as well as changes in NF-κB, caspase-11, NOX2, NOXO2, and eNOS/nNOS/iNOS expression/activity.

Keywords: NF-κB; NLRP3 inflammasome; NOS; NOX; inflammatory hyperalgesia; lipopolysaccharide.

MeSH terms

  • Animals
  • Apoptosis Regulatory Proteins / metabolism
  • CARD Signaling Adaptor Proteins
  • Caspase 1 / metabolism
  • Caspases / metabolism
  • Caspases, Initiator
  • Furans
  • Heterocyclic Compounds, 4 or More Rings / administration & dosage
  • Heterocyclic Compounds, 4 or More Rings / therapeutic use*
  • Hyperalgesia / drug therapy*
  • Hyperalgesia / pathology
  • Hyperalgesia / prevention & control
  • Indenes
  • Inflammasomes / antagonists & inhibitors*
  • Inflammasomes / chemistry
  • Inflammasomes / drug effects
  • Inflammation
  • Lipopolysaccharides
  • Male
  • Mice
  • Mice, Inbred BALB C
  • NADPH Oxidases / metabolism
  • NF-kappa B / metabolism
  • NLR Family, Pyrin Domain-Containing 3 Protein / antagonists & inhibitors*
  • NLR Family, Pyrin Domain-Containing 3 Protein / metabolism
  • Nitric Oxide Synthase / metabolism
  • Protein Isoforms / metabolism
  • Sulfonamides
  • Sulfones / administration & dosage
  • Sulfones / therapeutic use*

Substances

  • Apoptosis Regulatory Proteins
  • CARD Signaling Adaptor Proteins
  • Furans
  • Heterocyclic Compounds, 4 or More Rings
  • Indenes
  • Inflammasomes
  • Lipopolysaccharides
  • NF-kappa B
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • Nlrp3 protein, mouse
  • Protein Isoforms
  • Pycard protein, mouse
  • Sulfonamides
  • Sulfones
  • N-(1,2,3,5,6,7-hexahydro-S-indacen-4-ylcarbamoyl)-4-(2-hydroxy-2-propanyl)-2-furansulfonamide
  • Nitric Oxide Synthase
  • NADPH Oxidases
  • Casp4 protein, mouse
  • Caspases
  • Caspases, Initiator
  • Caspase 1