NLRP3 inflammasome-mediated neutrophil recruitment and hypernociception depend on leukotriene B(4) in a murine model of gout.

Abstract

OBJECTIVE:

Deposition of monosodium urate monohydrate (MSU) crystals in the joints promotes an intense inflammatory response and joint dysfunction. This study evaluated the role of the NLRP3 inflammasome and 5-lipoxygenase (5-LOX)-derived leukotriene B(4) (LTB(4) ) in driving tissue inflammation and hypernociception in a murine model of gout.

METHODS:

Gout was induced by injecting MSU crystals into the joints of mice. Wild-type mice and mice deficient in NLRP3, ASC, caspase 1, interleukin-1β (IL-1β), IL-1 receptor type I (IL-1RI), IL-18R, myeloid differentiation factor 88 (MyD88), or 5-LOX were used. Evaluations were performed to assess neutrophil influx, LTB(4) activity, cytokine (IL-1β, CXCL1) production (by enzyme-linked immunosorbent assay), synovial microvasculature cell adhesion (by intravital microscopy), and hypernociception. Cleaved caspase 1 and production of reactive oxygen species (ROS) were analyzed in macrophages by Western blotting and fluorometric assay, respectively.

RESULTS:

Injection of MSU crystals into the knee joints of mice induced neutrophil influx and neutrophil-dependent hypernociception. MSU crystal-induced neutrophil influx was CXCR2-dependent and relied on the induction of CXCL1 in an NLRP3/ASC/caspase 1/IL-1β/MyD88-dependent manner. LTB(4) was produced rapidly after injection of MSU crystals, and this was necessary for caspase 1-dependent IL-1β production and consequent release of CXCR2-acting chemokines in vivo. In vitro, macrophages produced LTB(4) after MSU crystal injection, and LTB(4) was relevant in the MSU crystal-induced maturation of IL-1β. Mechanistically, LTB(4) drove MSU crystal-induced production of ROS and ROS-dependent activation of the NLRP3 inflammasome.

CONCLUSION:

These results reveal the role of the NLRP3 inflammasome in mediating MSU crystal-induced inflammation and dysfunction of the joints, and highlight a previously unrecognized role of LTB(4) in driving NLRP3 inflammasome activation in response to MSU crystals, both in vitro and in vivo.

• Authors: Flávio A Amaral, Vivian V Costa, Livia D Tavares, Daniela Sachs, Fernanda M Coelho, Caio T Fagundes, Frederico M Soriani, Tatiana N Silveira, Larissa D Cunha, Dario S Zamboni, Valerie Quesniaux, Raphael S Peres, Thiago M Cunha, Fernando Q Cunha, Bernhard Ryffel, Daniele G Souza, Mauro M Teixeira
• Journal: Arthritis and rheumatism (Arthritis Rheum) Vol. 64 Issue 2 Pg. 474-84 (Feb 2012) ISSN: 1529-0131 [Electronic] United States
• PMID: 21952942 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2012 by the American College of Rheumatology.

Chemical References

• Carrier Proteins
• Cytokines
• Inflammasomes
• Interleukin-1beta
• NLR Family, Pyrin Domain-Containing 3 Protein
• Nlrp3 protein, mouse
• Reactive Oxygen Species
• Leukotriene B4
• Uric Acid
• Caspase 1

Topics

• Animals
• Carrier Proteins (metabolism)
• Caspase 1 (metabolism)
• Cytokines (metabolism)
• Gout (chemically induced, immunology, metabolism)
• Hyperalgesia (immunology, metabolism)
• Inflammasomes (immunology, metabolism)
• Inflammation (immunology, metabolism)
• Interleukin-1beta (metabolism)
• Leukotriene B4 (immunology, metabolism)
• Macrophages (immunology, metabolism)
• Male
• Mice
• Mice, Knockout
• NLR Family, Pyrin Domain-Containing 3 Protein
• Neutrophil Infiltration (physiology)
• Neutrophils (immunology, metabolism)
• Reactive Oxygen Species (metabolism)
• Synovial Membrane (immunology, metabolism)
• Uric Acid (pharmacology)