The Cyclopentenone Prostaglandin 15d-PGJ2 Inhibits the NLRP1 and NLRP3 Inflammasomes This information is current as Nolan K. Maier, Stephen H. Leppla and Mahtab Moayeri of October 1, 2021. J Immunol 2015; 194:2776-2785; Prepublished online 13 February 2015; doi: 10.4049/jimmunol.1401611 http://www.jimmunol.org/content/194/6/2776 Downloaded from Supplementary http://www.jimmunol.org/content/suppl/2015/02/13/jimmunol.140161 Material 1.DCSupplemental References This article cites 69 articles, 25 of which you can access for free at: http://www.jimmunol.org/ http://www.jimmunol.org/content/194/6/2776.full#ref-list-1 Why The JI? Submit online. • Rapid Reviews! 30 days* from submission to initial decision • No Triage! Every submission reviewed by practicing scientists by guest on October 1, 2021 • Fast Publication! 4 weeks from acceptance to publication *average Subscription Information about subscribing to The Journal of Immunology is online at: http://jimmunol.org/subscription Permissions Submit copyright permission requests at: http://www.aai.org/About/Publications/JI/copyright.html Email Alerts Receive free email-alerts when new articles cite this article. Sign up at: http://jimmunol.org/alerts The Journal of Immunology is published twice each month by The American Association of Immunologists, Inc., 1451 Rockville Pike, Suite 650, Rockville, MD 20852 All rights reserved. Print ISSN: 0022-1767 Online ISSN: 1550-6606. The Journal of Immunology The Cyclopentenone Prostaglandin 15d-PGJ2 Inhibits the NLRP1 and NLRP3 Inflammasomes Nolan K. Maier, Stephen H. Leppla, and Mahtab Moayeri Inflammasomes are cytosolic protein complexes that respond to diverse danger signals by activating caspase-1. The sensor components of the inflammasome, often proteins of the nucleotide-binding oligomerization domain–like receptor (NLR) family, 12,14 detect stress, danger stimuli, and pathogen-associated molecular patterns. We report that the eicosanoid 15-deoxy-D –PGJ2 (15d-PGJ2) and related cyclopentenone PGs inhibit caspase-1 activation by the NLR family leucine-rich repeat protein (NLRP)1 and NLRP3 inflammasomes. This inhibition was independent of the well-characterized role of 15d-PGJ2 as a peroxisome pro- liferator receptor-g agonist, its activation of NF erythroid 2–related factor 2, or its anti-inflammatory function as an inhibitor of NF-kB. Instead, 15d-PGJ2 prevents the autoproteolytic activation of caspase-1 and the maturation of IL-1b through induction of a cellular state inhibitory to caspase-1 proteolytic function. The eicosanoid does not directly modify or inactivate the caspase-1 enzyme. Rather, inhibition is dependent on de novo protein synthesis. In a mouse peritonitis model of gout, using monosodium Downloaded from urate crystals to activate NLRP3, 15d-PGJ2 caused a significant inhibition of cell recruitment and associated IL-1b release. Furthermore, in a murine anthrax infection model, 15d-PGJ2 reversed anthrax lethal toxin-mediated NLRP1-dependent resis- tance. The findings reported in this study suggest a novel mechanism for the anti-inflammatory properties of the cyclopentenone PGs through inhibition of caspase-1 and the inflammasome. The Journal of Immunology, 2015, 194: 2776–2785. he inflammasome is a multiprotein complex that forms in The PGs are lipid signaling molecules derived from arachidonic http://www.jimmunol.org/ response to a variety of danger signals. Upon activation, acid that have diverse functions. Production of PGs depends on T the sensor protein, often of the nucleotide-binding oligo- the action of the cyclooxygenase (COX) enzymes of which there merization domain–like receptor (NLR) family, recruits caspase-1 are two isoforms. COX-1 is expressed constitutively and predomi- (formerly IL-cleavage enzyme). Caspase-1 undergoes autopro- nantly produces prostanoids with housekeeping functions. COX-2 teolytic activation and cleaves the zymogen forms of the proin- is induced following inflammatory stimuli and is the dominant flammatory cytokines IL-1b and IL-18 to their mature forms, source of PGs during the inflammatory response. Most PGs exert which are then secreted from the cell. Caspase-1 activation also their effects through activation of specific transmembrane G pro- leads to a rapid form of lytic cell death termed pyroptosis (1). tein–coupled receptors. These receptors activate a varied set of by guest on October 1, 2021 Inflammasome function plays a key role in the innate immune intracellular signaling pathways that lead to diverse biological response to infection (2), and the mechanisms by which pathogens activities (3). Many PGs have demonstrated proinflammatory activate and evade inflammasome detection are an active area effects, but anti-inflammatory effects have been reported for of study. However, inflammasome signaling and the associated cyclopentenone PGs. Cyclopentenone PGs contain a highly re- cytokine responses or tissue necrosis are also associated with active a,b-unsaturated carbonyl that can form covalent attach- numerous inflammatory disorders, including type 2 diabetes, ments with thiol groups on proteins, thus altering their function Alzheimer’s disease, arthritis, macular degeneration, and asthma (4). These PGs inhibit proinflammatory NF-kB activity through (1). For this reason, discovery of novel inflammasome inhibitors is covalent modification of IKK as well as direct inhibition of NF-kB of clinical importance. binding to DNA (5–7). They also upregulate and activate anti- inflammatory heat shock proteins (HSPs) such as HSP70 (8). 12,14 15-Deoxy-D –PGJ2 (15d-PGJ2) is the best studied anti- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Dis- inflammatory PG. It is formed as a dehydration product of eases, National Institutes of Health, Bethesda, MD 20892 PGD (9) and was the first identified endogenous ligand of the Received for publication June 25, 2014. Accepted for publication January 8, 2015. 2 nuclear receptor peroxisome proliferator–activated receptor g This work was supported by the Intramural Research Program of the National Insti- tute of Allergy and Infectious Diseases. (PPARg) (10, 11). 15d-PGJ2 also activates the transcription factor NF erythroid 2–related factor 2 (NRF2) through formation of Address correspondence and reprint requests to Dr. Mahtab Moayeri, National In- stitutes of Health, Building 33, Room 1W20B, Bethesda, MD 20892. E-mail address: adducts with the NRF2 inhibitor KEAP1 (12). Both PPARg and [email protected] NRF2 are known to have anti-inflammatory roles (13, 14). It is The online version of this article contains supplemental material. through these actions that this lipid mediator can alter expression Abbreviations used in this article: BMDM, bone marrow–derived macrophage; COX, of cytokine, chemokine, and proinflammatory genes (15). A 12,14 cyclooxygenase; 15d-PGJ2, 15-deoxy-D –PGJ2; FlaTox, combination of anthrax number of studies have shown that 15d-PGJ has therapeutic po- protective Ag and fusion protein of N-terminal domain of anthrax lethal factor to 2 flagellin; FP59, fusion protein of N-terminal domain of anthrax lethal factor to the tential in animal models of inflammatory disease (for review, see ADP-ribosylating domain of Pseudomonas aeruginosa exotoxin A; HSP, heat shock Ref. 15). protein; LF, anthrax lethal factor; LFn-Fla, fusion protein of N-terminal domain of In this study, we report on a novel mechanism for the anti- anthrax lethal factor to flagellin; LT, anthrax lethal toxin (combination of anthrax protective Ag and anthrax lethal factor); MSU, monosodium urate; NLR, nucleotide- inflammatory actions of 15d-PGJ2 and related cyclopentenone binding oligomerization domain–like receptor; NLRP, nucleotide-binding oligomer- PGs. Our studies show that these PGs are potent inhibitors of the ization domain–like receptor family leucine-rich repeat protein; NRF2, NF erythroid 2–related factor 2; PA, anthrax protective Ag; PPARg, peroxisome proliferator– anthrax lethal toxin (LT) activation of the NLR family leucine-rich activated receptor g. repeat protein (NLRP)1 inflammasome and nigericin-mediated www.jimmunol.org/cgi/doi/10.4049/jimmunol.1401611 The Journal of Immunology 2777 activation of the NLRP3 inflammasome. These PGs inhibit in- with PBS (6 ml/mouse). Infiltrating cells were counted following eryth- flammasome-mediated activation of caspase-1 and, as a conse- rocyte lysis using ACK buffer (Life Technologies). IL-1b measurements in quence, prevent maturation and release of IL-1b, both in vitro and lavage fluids were made using an ELISA kit from R&D Systems (Min- neapolis, MN). in vivo, in a manner independent of effects on NF-kB. Our find- For sensitization of anthrax spore–resistant NLRP1bS-expressing mice, ings confirm the role of these lipid mediators as anti-inflammatory 15d-PGJ2 or vehicle was administered to BALB/cJ, C57BL/6J, C57BL/ agents and support their development as therapeutic agents for the 6NTac Nlrp1bS/S, or C57BL/6NTac Nlrp1bR;R mice (100 mg, 200 ml, s.c., 3 treatment of inflammatory diseases. at 5 min and 1 h after spore infection). Animals were infected with 2–4 107 A35 spores (200 ml, s.c.) and monitored for 7 d postinfection for signs of malaise or death. Materials and Methods All animal experiments were performed in strict accordance with Reagents guidelines from the National Institutes of Health and the Animal Welfare Act, approved by the Animal Care and Use Committee of the National 15d-PGJ2, CAY10410 (9,10-dihydro–15d-PGJ2), PGD2, PGE2, PGF2a, Institute of Allergy and Infectious Diseases, National Institutes of Health. rosiglitazone,