Selective NLRP3 (Pyrin Domain-Containing Protein 3) Inflammasome Inhibitor Reduces Brain Injury After Intracerebral Hemorrhage

Stroke. 2018 Jan;49(1):184-192. doi: 10.1161/STROKEAHA.117.018904. Epub 2017 Dec 6.

Abstract

Background and purpose: Intracerebral hemorrhage (ICH) is a devastating disease without effective treatment. As a key component of the innate immune system, the NOD-like receptor (NLR) family, NLRP3 (pyrin domain-containing protein 3) inflammasome, when activated after ICH, promotes neuroinflammation and brain edema. MCC950 is a potent, selective, small-molecule NLRP3 inhibitor that blocks NLRP3 activation at nanomolar concentrations. Here, we examined the effect of MCC950 on brain injury and inflammation in 2 models of ICH in mice.

Methods: In mice with ICH induced by injection of autologous blood or bacterial collagenase, we determined the therapeutic potential of MCC950 and its mechanisms of neuroprotection.

Results: MCC950 reduced IL-1β (interleukin-1β) production and attenuated neurodeficits and perihematomal brain edema after ICH induction by injection of either autologous blood or collagenase. In mice with autologous blood-induced ICH, the protection of MCC950 was associated with reduced leukocyte infiltration into the brain and microglial production of IL-6. MCC950 improved blood-brain barrier integrity and diminished cell death. Notably, the protective effect of MCC950 was abolished in mice depleted of either microglia or Gr-1+ myeloid cells.

Conclusions: These results indicate that the NLRP3 inflammasome inhibitor, MCC950, attenuates brain injury and inflammation after ICH. Hence, NLRP3 inflammasome inhibition is a potential therapy for ICH that warrants further investigation.

Keywords: brain edema; cell death; inflammation; neuroprotection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain Injuries / drug therapy*
  • Brain Injuries / etiology
  • Brain Injuries / metabolism
  • Brain Injuries / pathology
  • Cerebral Hemorrhage / complications
  • Cerebral Hemorrhage / drug therapy*
  • Cerebral Hemorrhage / metabolism
  • Cerebral Hemorrhage / pathology
  • Female
  • Interleukin-1beta / metabolism
  • Male
  • Mice
  • NLR Family, Pyrin Domain-Containing 3 Protein / antagonists & inhibitors*
  • NLR Family, Pyrin Domain-Containing 3 Protein / metabolism

Substances

  • IL1B protein, mouse
  • Interleukin-1beta
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • Nlrp3 protein, mouse