Annexin-A1 tripeptide attenuates surgery-induced neuroinflammation and memory deficits through regulation of the NLRP3 inflammasome

AbstractNeuroinflammation is a growing hallmark of perioperative neurocognitive disorders (PNDs), including delirium and longer-lasting cognitive deficits. We have developed a clinically-relevant orthopedic mouse model to study the impact of a common surgical procedure on the vulnerable brain. The mechanism underlying PNDs remain unknown. Here we evaluated the impact of surgical trauma on the NLRP3 inflammasome signaling, including the expression of apoptosis-associated speck-like protein containing a CARD (ASC), caspase-1, and IL-1β in the hippocampus of C57BL6/J male mice, adult (3-months) and aged (>18-months). Surgery triggered ASC specks formation in CA1 hippocampal microglia, but without inducing significant morphological changes in NLRP3 and ASC knockout mice. Since no therapies are currently available to treat PNDs, we assessed the neuroprotective effects of a biomimetic peptide derived from the endogenous inflammation-ending molecule, Annexin-A1 (ANXA1). We tested the hypothesis that this peptide (ANXA1sp) inhibits NLRP3 inflammasome activation, thus preventing microglial activation and hippocampal-dependent memory deficits. Together these results uncover a previously underrecognized role of the NLRP3 inflammasome in triggering postoperative neuroinflammation and offer a new target for advancing treatment of PNDs through resolution of inflammation.

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Role of Annexin A1 in NLRP3 Inflammasome Activation in Murine Neutrophils

Cells ◽

10.3390/cells10010121 ◽

2021 ◽

Vol 10 (1) ◽

pp. 121

Author(s):

José Marcos Sanches ◽

Rebeca D. Correia-Silva ◽

Gustavo H. B. Duarte ◽

Anna Maria A. P. Fernandes ◽

Salvador Sánchez-Vinces ◽

...

Keyword(s):

Knockout Mice ◽

Nlrp3 Inflammasome ◽

Cell Stress ◽

Lipid Biomarkers ◽

Inflammasome Activation ◽

Annexin A1 ◽

Wild Type ◽

Caspase 1 ◽

Nlrp3 Inflammasome Activation

This study evaluated the role of endogenous and exogenous annexin A1 (AnxA1) in the activation of the NLRP3 inflammasome in isolated peritoneal neutrophils. C57BL/6 wild-type (WT) and AnxA1 knockout mice (AnxA1-/-) received 0.3% carrageenan intraperitoneally and, after 3 h, the peritoneal exudate was collected. WT and AnxA1-/- neutrophils were then stimulated with lipopolysaccharide, followed by the NLRP3 agonists nigericin or ATP. To determine the exogenous effect of AnxA1, the neutrophils were pretreated with the AnxA1-derived peptide Ac2-26 followed by the NLRP3 agonists. Ac2-26 administration reduced NLRP3-derived IL-1β production by WT neutrophils after nigericin and ATP stimulation. However, IL-1β release was impaired in AnxA1-/- neutrophils stimulated by both agonists, and there was no further impairment in IL-1β release with Ac2-26 treatment before stimulation. Despite this, ATP- and nigericin-stimulated AnxA1-/- neutrophils had increased levels of cleaved caspase-1. The lipidomics of supernatants from nigericin-stimulated WT and AnxA1-/- neutrophils showed potential lipid biomarkers of cell stress and activation, including specific sphingolipids and glycerophospholipids. AnxA1 peptidomimetic treatment also increased the concentration of phosphatidylserines and oxidized phosphocholines, which are lipid biomarkers related to the inflammatory resolution pathway. Together, our results indicate that exogenous AnxA1 negatively regulates NLRP3-derived IL-1β production by neutrophils, while endogenous AnxA1 is required for the activation of the NLRP3 machinery.

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Ethyl Pyruvate Attenuates Microglial NLRP3 Inflammasome Activation via Inhibition of HMGB1/NF-κB/miR-223 Signaling

Antioxidants ◽

10.3390/antiox10050745 ◽

2021 ◽

Vol 10 (5) ◽

pp. 745

Author(s):

Melis Olcum ◽

Kemal Ugur Tufekci ◽

Devrim Yagmur Durur ◽

Bora Tastan ◽

Irem Nur Gokbayrak ◽

...

Keyword(s):

Nlrp3 Inflammasome ◽

Ethyl Pyruvate ◽

Metabolic Effects ◽

Inflammasome Activation ◽

Neuroprotective Effects ◽

Cellular Models ◽

Nlrp3 Inflammasome Activation ◽

Parkinson’S Diseases ◽

Anti Inflammatory ◽

The Impact

Ethyl pyruvate is a molecule with anti-inflammatory and pro-metabolic effects. Ethyl pyruvate has been shown to ameliorate the clinical and pathological findings of neurodegenerative diseases such as Alzheimer’s and Parkinson’s Diseases in rodents. Its anti-inflammatory and neuroprotective effects are widely investigated in animal and cellular models. Our study aimed to investigate the mechanism of the impact of Ethyl pyruvate on NLRP3 inflammasome activation in the N9 microglial cell line. Our results indicated that ethyl pyruvate significantly suppressed LPS and ATP-induced NLRP3 inflammasome activation, decreased active caspase-1 level, secretion of IL-1β and IL-18 cytokines, and reduced the level of pyroptotic cell death resulting from inflammasome activation. Furthermore, ethyl pyruvate reduced the formation of total and mitochondrial ROS and suppressed inflammasome-induced HMGB1 upregulation and nuclear NF-κB translocation and reversed the inflammasome activation-induced miRNA expression profile for miR-223 in N9 cells. Our study suggests that ethyl pyruvate effectively suppresses the NLRP3 inflammasome activation in microglial cells regulation by miR-223 and NF-κB/HMGB1 axis.

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Annexin A1 Regulates NLRP3 Inflammasome Activation and Modifies Lipid Release Profile in Isolated Peritoneal Macrophages

Cells ◽

10.3390/cells9040926 ◽

2020 ◽

Vol 9 (4) ◽

pp. 926 ◽

Cited By ~ 5

Author(s):

José Marcos Sanches ◽

Laura Migliari Branco ◽

Gustavo Henrique Bueno Duarte ◽

Sonia Maria Oliani ◽

Karina Ramalho Bortoluci ◽

...

Keyword(s):

Nlrp3 Inflammasome ◽

Peritoneal Macrophages ◽

Lipid Mediator ◽

Inflammasome Activation ◽

Annexin A1 ◽

Wild Type ◽

Inflammatory Protein ◽

Nlrp3 Inflammasome Activation ◽

Macrophage Viability

Annexin A1 (AnxA1) is a potent anti-inflammatory protein that downregulates proinflammatory cytokine release. This study evaluated the role of AnxA1 in the regulation of NLRP3 inflammasome activation and lipid release by starch-elicited murine peritoneal macrophages. C57bl/6 wild-type (WT) and AnxA1-null (AnxA1-/-) mice received an intraperitoneal injection of 1.5% starch solution for macrophage recruitment. NLRP3 was activated by priming cells with lipopolysaccharide for 3 h, followed by nigericin (1 h) or ATP (30 min) incubation. As expected, nigericin and ATP administration decreased elicited peritoneal macrophage viability and induced IL-1β release, more pronounced in the AnxA1-/- cells than in the control peritoneal macrophages. In addition, nigericin-activated AnxA1-/- macrophages showed increased levels of NLRP3, while points of co-localization of the AnxA1 protein and NLRP3 inflammasome were detected in WT cells, as demonstrated by ultrastructural analysis. The lipidomic analysis showed a pronounced release of prostaglandins in nigericin-stimulated WT peritoneal macrophages, while ceramides were detected in AnxA1-/- cell supernatants. Different eicosanoid profiles were detected for both genotypes, and our results suggest that endogenous AnxA1 regulates the NLRP3-derived IL-1β and lipid mediator release in macrophages.

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Faculty Opinions recommendation of The role of lysosomal cysteine cathepsins in NLRP3 inflammasome activation.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.735165969.793559816 ◽

2019 ◽

Author(s):

Paras Anand

Keyword(s):

Nlrp3 Inflammasome ◽

Inflammasome Activation ◽

Cysteine Cathepsins ◽

Nlrp3 Inflammasome Activation

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Porphyromonas Gingivalis Infection Induces Synaptic Failure via Increased IL-1β Production in Leptomeningeal Cells

Journal of Alzheimer s Disease ◽

10.3233/jad-210031 ◽

2021 ◽

pp. 1-17

Author(s):

Wanyi Huang ◽

Fan Zeng ◽

Yebo Gu ◽

Muzhou Jiang ◽

Xinwen Zhang ◽

...

Keyword(s):

Porphyromonas Gingivalis ◽

Nlrp3 Inflammasome ◽

Cortical Neurons ◽

Inflammasome Activation ◽

Memory Decline ◽

Periodontal Bacteria ◽

Nlrp3 Inflammasome Activation ◽

Synaptic Failure ◽

Pre Treatment ◽

The Impact

Background: Studies have reported that synaptic failure occurs before the Alzheimer’s disease (AD) onset. The systemic Porphyromonas gingivalis (P. gingivalis) infection is involved in memory decline. We previously showed that leptomeningeal cells, covering the brain, activate glial cells by releasing IL-1β in response to systemic inflammation. Objective: In the present study, we focused on the impact of leptomeningeal cells on neurons during systemic P. gingivalis infection. Methods: The responses of leptomeningeal cells and cortical neurons to systemic P. gingivalis infection were examined in 15-month-old mice. The mechanism of IL-1β production by P. gingivalis infected leptomeningeal cells was examined, and primary cortical neurons were treated with P. gingivalis infected leptomeningeal cells condition medium (Pg LCM). Results: Systemic P. gingivalis infection increased the expression of IL-1β in leptomeninges and reduced the synaptophysin (SYP) expression in leptomeninges proximity cortex in mice. Leptomeningeal cells phagocytosed P. gingivalis resulting in lysosomal rupture and Cathepsin B (CatB) leakage. Leaked CatB mediated NLRP3 inflammasome activation inducing IL-1β secretion in leptomeningeal cells. Pg LCM decreased the expression of synaptic molecules, including SYP, which was inhibited by an IL-1 receptor antagonist pre-treatment. Conclusion: These observations demonstrate that P. gingivalis infection is involved in synaptic failure by inducing CatB/NLRP3 inflammasome-mediated IL-1β production in leptomeningeal cells. The periodontal bacteria-induced synaptic damage may accelerate the onset and cognitive decline of AD.

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The NLRP3 Inflammasome as a Novel Player of the Intercellular Crosstalk in Metabolic Disorders

Mediators of Inflammation ◽

10.1155/2013/678627 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 48

Author(s):

Elisa Benetti ◽

Fausto Chiazza ◽

Nimesh S. A. Patel ◽

Massimo Collino

Keyword(s):

Chronic Inflammation ◽

Nlrp3 Inflammasome ◽

Metabolic Disorders ◽

Inflammasome Activation ◽

Nucleotide Binding Domain ◽

Metabolic Inflammation ◽

Nlrp3 Inflammasome Activation ◽

Leucine Rich Repeat Protein

The combination of obesity and type 2 diabetes is a serious health problem, which is projected to afflict 300 million people worldwide by 2020. Both clinical and translational laboratory studies have demonstrated that chronic inflammation is associated with obesity and obesity-related conditions such as insulin resistance. However, the precise etiopathogenetic mechanisms linking obesity to diabetes remain to be elucidated, and the pathways that mediate this phenomenon are not fully characterized. One of the most recently identified signaling pathways, whose activation seems to affect many metabolic disorders, is the “inflammasome,” a multiprotein complex composed of NLRP3 (nucleotide-binding domain and leucine-rich repeat protein 3), ASC (apoptosis-associated speck-like protein containing a CARD), and procaspase-1. NLRP3 inflammasome activation leads to the processing and secretion of the proinflammatory cytokines interleukin- (IL-) 1βand IL-18. The goal of this paper is to review new insights on the effects of the NLRP3 inflammasome activation in the complex mechanisms of crosstalk between different organs, for a better understanding of the role of chronic inflammation in metabolic disease pathogenesis. We will provide here a perspective on the current research on NLRP3 inflammasome, which may represent an innovative therapeutic target to reverse the detrimental metabolic consequences of the metabolic inflammation.

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Progesterone Attenuates Stress-Induced NLRP3 Inflammasome Activation and Enhances Autophagy Following Ischemic Brain Injury

International Journal of Molecular Sciences ◽

10.3390/ijms21113740 ◽

2020 ◽

Vol 21 (11) ◽

pp. 3740 ◽

Cited By ~ 3

Author(s):

Claudia Espinosa-Garcia ◽

Fahim Atif ◽

Seema Yousuf ◽

Iqbal Sayeed ◽

Gretchen N. Neigh ◽

...

Keyword(s):

Brain Injury ◽

Nlrp3 Inflammasome ◽

Molecular Mechanisms ◽

Global Ischemia ◽

Inflammasome Activation ◽

Ischemic Brain Injury ◽

Primary Microglia ◽

Ischemic Brain ◽

Nlrp3 Inflammasome Activation ◽

The Impact

NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome inhibition and autophagy induction attenuate inflammation and improve outcome in rodent models of cerebral ischemia. However, the impact of chronic stress on NLRP3 inflammasome and autophagic response to ischemia remains unknown. Progesterone (PROG), a neuroprotective steroid, shows promise in reducing excessive inflammation associated with poor outcome in ischemic brain injury patients with comorbid conditions, including elevated stress. Stress primes microglia, mainly by the release of alarmins such as high-mobility group box-1 (HMGB1). HMGB1 activates the NLRP3 inflammasome, resulting in pro-inflammatory interleukin (IL)-1β production. In experiment 1, adult male Sprague-Dawley rats were exposed to social defeat stress for 8 days and then subjected to global ischemia by the 4-vessel occlusion model, a clinically relevant brain injury associated with cardiac arrest. PROG was administered 2 and 6 h after occlusion and then daily for 7 days. Animals were killed at 7 or 14 days post-ischemia. Here, we show that stress and global ischemia exert a synergistic effect in HMGB1 release, resulting in exacerbation of NLRP3 inflammasome activation and autophagy impairment in the hippocampus of ischemic animals. In experiment 2, an in vitro inflammasome assay, primary microglia isolated from neonatal brain tissue, were primed with lipopolysaccharide (LPS) and stimulated with adenosine triphosphate (ATP), displaying impaired autophagy and increased IL-1β production. In experiment 3, hippocampal microglia isolated from stressed and unstressed animals, were stimulated ex vivo with LPS, exhibiting similar changes than primary microglia. Treatment with PROG reduced HMGB1 release and NLRP3 inflammasome activation, and enhanced autophagy in stressed and unstressed ischemic animals. Pre-treatment with an autophagy inhibitor blocked Progesterone’s (PROG’s) beneficial effects in microglia. Our data suggest that modulation of microglial priming is one of the molecular mechanisms by which PROG ameliorates ischemic brain injury under stressful conditions.

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The gut microbial metabolite trimethylamine N-oxide aggravates GVHD by inducing M1 macrophage polarization in mice

Blood ◽

10.1182/blood.2019003990 ◽

2020 ◽

Vol 136 (4) ◽

pp. 501-515 ◽

Cited By ~ 8

Author(s):

Kunpeng Wu ◽

Yan Yuan ◽

Huihui Yu ◽

Xin Dai ◽

Shu Wang ◽

...

Keyword(s):

Nlrp3 Inflammasome ◽

Macrophage Polarization ◽

Short Chain Fatty Acids ◽

Inflammasome Activation ◽

Microbial Metabolites ◽

M1 Macrophage ◽

The Impact

Abstract The diversity of the human microbiome heralds the difference of the impact that gut microbial metabolites exert on allogenic graft-versus-host (GVH) disease (GVHD), even though short-chain fatty acids and indole were demonstrated to reduce its severity. In this study, we dissected the role of choline-metabolized trimethylamine N-oxide (TMAO) in the GVHD process. Either TMAO or a high-choline diet enhanced the allogenic GVH reaction, whereas the analog of choline, 3,3-dimethyl-1-butanol reversed TMAO-induced GVHD severity. Interestingly, TMAO-induced alloreactive T-cell proliferation and differentiation into T-helper (Th) subtypes was seen in GVHD mice but not in in vitro cultures. We thus investigated the role of macrophage polarization, which was absent from the in vitro culture system. F4/80+CD11b+CD16/32+ M1 macrophage and signature genes, IL-1β, IL-6, TNF-α, CXCL9, and CXCL10, were increased in TMAO-induced GVHD tissues and in TMAO-cultured bone marrow–derived macrophages (BMDMs). Inhibition of the NLRP3 inflammasome reversed TMAO-stimulated M1 features, indicating that NLRP3 is the key proteolytic activator involved in the macrophage’s response to TMAO stimulation. Consistently, mitochondrial reactive oxygen species and enhanced NF-κB nuclear relocalization were investigated in TMAO-stimulated BMDMs. In vivo depletion of NLRP3 in GVHD recipients not only blocked M1 polarization but also reversed GVHD severity in the presence of TMAO treatment. In conclusion, our data revealed that TMAO-induced GVHD progression resulted from Th1 and Th17 differentiation, which is mediated by the polarized M1 macrophage requiring NLRP3 inflammasome activation. It provides the link among the host choline diet, microbial metabolites, and GVH reaction, shedding light on alleviating GVHD by controlling choline intake.

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