CLEC5A knockdown protects against the cardiac dysfunction after Myocardial infarction by suppressing macrophage polarization, NLRP3 inflammasome activation and pyroptosis

2021 ◽  
Author(s):  
Xin Wang ◽  
Yu Hu ◽  
Yaguang Wang ◽  
Dapeng Shen ◽  
Guizhou Tao
Keyword(s):  
Myocardial Infarction ◽  
Nlrp3 Inflammasome ◽  
Cardiac Dysfunction ◽  
Macrophage Polarization ◽  
Left Ventricular ◽  
Receptor Protein ◽  
Inflammasome Activation ◽  
M1 Polarization

Increasing evidence has shown that NOD-like receptor protein 3 (NLRP3) inflammasome and pyroptotic cell death play vital roles in the pathophysiology of myocardial infarction (MI), a common cardiovascular disease characterized with cardiac dysfunction. C-type lectin member 5A (CLEC5A) is reported to strongly associate with activation of NLRP3 inflammasome and pyroptosis. In this study, in vivo MI model was established by the ligation of left anterior descending coronary artery on male C57BL/6 mice, and CLEC5A knockdown was further achieved by intra-myocardial injection of adenovirus delivering shRNA-CLEC5A. CLEC5A was found to be highly expressed in left ventricular of MI mice, while CLEC5A knockdown conversely alleviated the cardiac dysfunction in MI mice. Besides, MI-induced classical activation of macrophages was significantly inhibited after CLEC5A silencing. Additionally, CLEC5A knockdown dramatically inhibited MI-triggered activation of NLRP3 inflammasome, pyroptosis and NF-κB signaling in left ventricular of mice. In vitro experiment further validated that CLEC5A knockdown suppressed M1 polarization in LPS/IFNγ-stimulated RAW264.7 cells, and inhibited the polarized RAW264.7-induced activation of NLRP3 inflammasome/pyroptosis signaling in co-cultured cardiomyocytes. In conclusion, CLEC5A knockdown protects against the MI-induced cardiac dysfunction by regulating macrophage polarization, NLRP3 inflammasome and cell pyroptosis.

Kaempferol Alleviates Corneal Transplantation Rejection by Inhibiting NLRP3 Inflammasome Activation and Macrophage M1 Polarization via Promoting Autophagy

2021 ◽  
Author(s):  
Huiwen Tian ◽  
Shumei Lin ◽  
Jing Wu ◽  
Ming Ma ◽  
Jian Yu ◽  
...  
Keyword(s):  
Nlrp3 Inflammasome ◽  
Macrophage Polarization ◽  
Corneal Transplantation ◽  
Inflammasome Activation ◽  
M1 Polarization ◽  
Nlrp3 Inflammasome Activation ◽  
M1 Macrophage ◽  
Transplantation Rejection

Abstract Corneal transplantation rejection remains a major threat to the success rate in high-risk patients. Given the many side effects presented by traditional immunosuppressants, there is an urgency to clarify the mechanism of corneal transplantation rejection and to identify new therapeutic targets. Kaempferol is a natural flavonoid that has been proven in various studies to possess anti-inflammatory, antioxidant, anticancer, and neuroprotective properties. However, the relationship between kaempferol and corneal transplantation remains largely unexplored. To address this, both in vivo and in vitro, we established a model of corneal allograft transplantation in Wistar rats and an LPS-induced inflammatory model in THP-1 derived human macrophages. In the transplantation experiments, we observed an enhancement in the NLRP3 / IL-1 β axis and in M1 macrophage polarization post-operation. In groups to which kaempferol intraperitoneal injections were administered, this response was effectively reduced. However, the effect of kaempferol was reversed after the application of autophagy inhibitors. Similarly, in the inflammatory model, we found that different concentrations of kaempferol can reduce the LPS-induced M1 polarization and NLRP3 inflammasome activation. Moreover, we confirmed that kaempferol induced autophagy and that autophagy inhibitors reversed the effect in macrophages. In conclusion, we found that kaempferol can inhibit the activation of the NLRP3 inflammasomes by inducing autophagy, thus inhibiting macrophage polarization, and ultimately alleviating corneal transplantation rejection. Thus, our study suggests that kaempferol could be used as a potential therapeutic agent in the treatment of allograft rejection.

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

Blood ◽  
2020 ◽  
Vol 136 (4) ◽  
pp. 501-515 ◽  
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.

scholarly journals Koumine Suppresses IL-1β Secretion and Attenuates Inflammation Associated With Blocking ROS/NF-κB/NLRP3 Axis in Macrophages

2021 ◽  
Vol 11 ◽  
Author(s):  
Yufei Luo ◽  
Bojun Xiong ◽  
Haiping Liu ◽  
Zehong Chen ◽  
Huihui Huang ◽  
...  
Keyword(s):  
Nlrp3 Inflammasome ◽  
Inflammatory Diseases ◽  
Inhibitory Effect ◽  
Receptor Protein ◽  
Mechanistic Study ◽  
Inflammasome Activation ◽  
Nlrp3 Inflammasome Activation ◽  
Underlying Mechanisms

Koumine (KM), one of the primary constituents of Gelsemium elegans, has been used for the treatment of inflammatory diseases such as rheumatoid arthritis, but whether KM impacts the activation of the NOD-like receptor protein 3 (NLRP3) inflammasome remains unknown. This study aimed to explore the inhibitory effect of KM on NLRP3 inflammasome activation and the underlying mechanisms both in vitro using macrophages stimulated with LPS plus ATP, nigericin or monosodium urate (MSU) crystals and in vivo using an MSU-induced peritonitis model. We found that KM dose-dependently inhibited IL-1β secretion in macrophages after NLRP3 inflammasome activators stimulation. Furthermore, KM treatment efficiently attenuated the infiltration of neutrophils and suppressed IL-1β production in mice with MSU-induced peritonitis. These results indicated that KM inhibited NLRP3 inflammasome activation, and consistent with this finding, KM effectively inhibited caspase-1 activation, mature IL-1β secretion, NLRP3 formation and pro-IL-1β expression in LPS-primed macrophages treated with ATP, nigericin or MSU. The mechanistic study showed that, KM exerted a potent inhibitory effect on the NLRP3 priming step, which decreased the phosphorylation of IκBα and p65, the nuclear localization of p65, and the secretion of TNF-α and IL-6. Moreover, the assembly of NLRP3 was also interrupted by KM. KM blocked apoptosis-associated speck-like protein containing a CARD (ASC) speck formation and its oligomerization and hampered the NLRP3-ASC interaction. This suppression was attributed to the ability of KM to inhibit the production of reactive oxygen species (ROS). In support of this finding, the inhibitory effect of KM on ROS production was completely counteracted by H2O2, an ROS promoter. Our results provide the first indication that KM exerts an inhibitory effect on NLRP3 inflammasome activation associated with blocking the ROS/NF-κB/NLRP3 signal axis. KM might have potential clinical application in the treatment of NLRP3 inflammasome-related diseases.

scholarly journals UAF1 deubiquitinase complexes facilitate NLRP3 inflammasome activation by promoting NLRP3 expression

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Hui Song ◽  
Chunyuan Zhao ◽  
Zhongxia Yu ◽  
Qizhao Li ◽  
Rongzhen Yan ◽  
...  
Keyword(s):  
Nlrp3 Inflammasome ◽  
Inflammatory Diseases ◽  
Receptor Protein ◽  
Inflammasome Activation ◽  
Danger Signals ◽  
Nlrp3 Inflammasome Activation ◽  
Microbial Infections ◽  
Nlrp3 Expression

AbstractNOD-like receptor protein 3 (NLRP3) detects microbial infections or endogenous danger signals and activates the NLRP3 inflammasome, which has important functions in host defense and contributes to the pathogenesis of inflammatory diseases, and thereby needs to be tightly controlled. Deubiquitination of NLRP3 is considered a key step in NLRP3 inflammasome activation. However, the mechanisms by which deubiquitination controls NLRP3 inflammasome activation are unclear. Here, we show that the UAF1/USP1 deubiquitinase complex selectively removes K48-linked polyubiquitination of NLRP3 and suppresses its ubiquitination-mediated degradation, enhancing cellular NLRP3 levels, which are indispensable for subsequent NLRP3 inflammasome assembly and activation. In addition, the UAF1/USP12 and UAF1/USP46 complexes promote NF-κB activation, enhance the transcription of NLRP3 and proinflammatory cytokines (including pro-IL-1β, TNF, and IL-6) by inhibiting ubiquitination-mediated degradation of p65. Consequently, Uaf1 deficiency attenuates NLRP3 inflammasome activation and IL-1β secretion both in vitro and in vivo. Our study reveals that the UAF1 deubiquitinase complexes enhance NLRP3 and pro-IL-1β expression by targeting NLRP3 and p65 and licensing NLRP3 inflammasome activation.

scholarly journals Cicadidae Periostracum Attenuates Atopic Dermatitis Symptoms and Pathology via the Regulation of NLRP3 Inflammasome Activation

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Gunhyuk Park ◽  
Byeong Cheol Moon ◽  
Seung Mok Ryu ◽  
Wook Jin Kim ◽  
Hye-Sun Lim
Keyword(s):  
Atopic Dermatitis ◽  
House Dust ◽  
House Dust Mite ◽  
Nlrp3 Inflammasome ◽  
Receptor Protein ◽  
Inflammasome Activation ◽  
Nlrp3 Inflammasome Activation ◽  
Dust Mite

Atopic dermatitis (AD) is a multifactorial inflammatory skin disease of complex etiology. Despite its increasing prevalence, treatment for AD is still limited. Crude drugs, including herbal extracts or natural resources, are being used to treat AD symptoms, with minimum side effects. Cicadidae Periostracum (CP), derived from the slough of insects belonging to the family Cicadidae, is a commonly used crude drug in traditional Asian medicine to treat/control epilepsy, shock, and edema. However, the effect of CP on AD-like skin lesions is unknown. In this study, we examined the effect of a CP water extract on AD disease development in vivo, using a house dust mite-induced AD mouse model, and in vitro, using HaCaT keratinocytes and a 3D human skin equivalent system. Importantly, CP administration alleviated house dust mite-induced AD-like symptoms, suggested by the quantified dermatitis scores, animal scratching behaviors, skin moisture retention capacity, and skin lesion and ear thickness. Furthermore, histopathological analysis demonstrated that CP decreased intralesional mast cell infiltration. In addition, CP treatments decreased the systemic levels of immunoglobulin E, histamine, and thymic stromal lymphopoietin (TSLP) and the local mRNA expression of TSLP and several Th1/Th2 cytokines. Our data suggest that these effects were mediated by the inhibition of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome activation. In vivo and in vitro CP treatments resulted in the downregulation of inflammasome components, such as ASC and cleaved caspase-1, as well as related mediators such as IL-1β and reactive oxygen species. Collectively, our results suggest that CP is a potential therapeutic agent for AD, controlling inflammatory responses through the suppression of NLRP3 inflammasome activation.

scholarly journals H3 Relaxin Alleviates Migration, Apoptosis and Pyroptosis Through P2X7R-Mediated Nucleotide Binding Oligomerization Domain-Like Receptor Protein 3 Inflammasome Activation in Retinopathy Induced by Hyperglycemia

2020 ◽  
Vol 11 ◽  
Author(s):  
Kelaier Yang ◽  
Jiannan Liu ◽  
Xiaohui Zhang ◽  
Ziqi Ren ◽  
Lei Gao ◽  
...  
Keyword(s):  
Nlrp3 Inflammasome ◽  
Inhibitory Effect ◽  
Receptor Protein ◽  
Inflammasome Activation ◽  
Sprague Dawley ◽  
Nlrp3 Inflammasome Activation ◽  
Underlying Mechanisms ◽  
And Migration

Introduction: P2X7R excitation-interrelated NLRP3 inflammasome activation induced by high glucose contributes to the pathogenesis of diabetic retinopathy (DR). Relaxin-3 is a bioactive peptide with a structure similar to insulin, which has been reported to be effective in diabetic cardiomyopathy models in vivo and in vitro. However, it is not known whether relaxin-3 has a beneficial impact on DR, and the underlying mechanisms of the effect are also remain unknown.Methods and Results: The retinas of male streptozotocin (STZ)-induced diabetic Sprague-Dawley (SD) rats were characterized. Human retinal microvascular endothelial cells (HRMECs) were used to evaluate the anti-inflammatory, antiapoptotic, antipyroptotic and anti-migration effects of H3 relaxin by transmission electron microscopy, wound-healing assay, transwell assay, flow cytometry, cytokine assays and western-blot analysis. After H3 relaxin treatment, changes of the ultrastructure and expression of NLRP3 inflammasome related proteins in the retinas of rats were compared with those in the diabetic group. In vitro, H3 relaxin played a beneficial role that decreased cell inflammation, apoptosis, pyroptosis and migration stimulated by advanced glycation end products (AGEs). Moreover, inhibition of P2X7R and NLRP3 inflammasome activation decreased NLRP3 inflammasome-mediated injury that similar to the effects of H3 relaxin. H3 relaxin suppressed the stimulation of apoptosis, pyroptosis and migration of HRMECs in response to AGEs mediated by P2X7R activation of the NLRP3 inflammasome.Conclusion: Our findings provide new insights into the mechanisms of the inhibitory effect of H3 relaxin on AGE-induced retinal injury, including migration, apoptosis and pyroptosis, mediated by P2X7R-dependent activation of the NLRP3 inflammasome in HRMECs.

scholarly journals The Role of Melatonin on NLRP3 Inflammasome Activation in Diseases

Antioxidants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1020
Author(s):  
Burak Ibrahim Arioz ◽  
Emre Tarakcioglu ◽  
Melis Olcum ◽  
Sermin Genc
Keyword(s):  
Nlrp3 Inflammasome ◽  
Intracellular Signaling ◽  
Metabolic Diseases ◽  
Metabolic Stress ◽  
Clinical Importance ◽  
Rapid Identification ◽  
In Vivo Studies ◽  
Inflammasome Activation

NLRP3 inflammasome is a part of the innate immune system and responsible for the rapid identification and eradication of pathogenic microbes, metabolic stress products, reactive oxygen species, and other exogenous agents. NLRP3 inflammasome is overactivated in several neurodegenerative, cardiac, pulmonary, and metabolic diseases. Therefore, suppression of inflammasome activation is of utmost clinical importance. Melatonin is a ubiquitous hormone mainly produced in the pineal gland with circadian rhythm regulatory, antioxidant, and immunomodulatory functions. Melatonin is a natural product and safer than most chemicals to use for medicinal purposes. Many in vitro and in vivo studies have proved that melatonin alleviates NLRP3 inflammasome activity via various intracellular signaling pathways. In this review, the effect of melatonin on the NLRP3 inflammasome in the context of diseases will be discussed.

scholarly journals Adropin-based dual treatment enhances the therapeutic potential of mesenchymal stem cells in rat myocardial infarction

2021 ◽  
Vol 12 (6) ◽  
Author(s):  
HuiYa Li ◽  
DanQing Hu ◽  
Guilin Chen ◽  
DeDong Zheng ◽  
ShuMei Li ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Therapeutic Potential ◽  
Left Ventricular ◽  
Left Ventricular Ejection ◽  
Paracrine Factors ◽  
Dual Treatment

AbstractBoth weak survival ability of stem cells and hostile microenvironment are dual dilemma for cell therapy. Adropin, a bioactive substance, has been demonstrated to be cytoprotective. We therefore hypothesized that adropin may produce dual protective effects on the therapeutic potential of stem cells in myocardial infarction by employing an adropin-based dual treatment of promoting stem cell survival in vitro and modifying microenvironment in vivo. In the current study, adropin (25 ng/ml) in vitro reduced hydrogen peroxide-induced apoptosis in rat bone marrow mesenchymal stem cells (MSCs) and improved MSCs survival with increased phosphorylation of Akt and extracellular regulated protein kinases (ERK) l/2. Adropin-induced cytoprotection was blocked by the inhibitors of Akt and ERK1/2. The left main coronary artery of rats was ligated for 3 or 28 days to induce myocardial infarction. Bromodeoxyuridine (BrdU)-labeled MSCs, which were in vitro pretreated with adropin, were in vivo intramyocardially injected after ischemia, following an intravenous injection of 0.2 mg/kg adropin (dual treatment). Compared with MSCs transplantation alone, the dual treatment with adropin reported a higher level of interleukin-10, a lower level of tumor necrosis factor-α and interleukin-1β in plasma at day 3, and higher left ventricular ejection fraction and expression of paracrine factors at day 28, with less myocardial fibrosis and higher capillary density, and produced more surviving BrdU-positive cells at day 3 and 28. In conclusion, our data evidence that adropin-based dual treatment may enhance the therapeutic potential of MSCs to repair myocardium through paracrine mechanism via the pro-survival pathways.

Pharmacological Blocker of NF-κb and Mitochondrial Ros Restrict NLRP3 Inflammasome Activation and Rescue Dopaminergic Neurons in Vitro and in Vivo Parkinson’s Disease

2021 ◽  
Author(s):  
Sahabuddin Ahmed ◽  
Samir Ranjan Panda ◽  
Mohit Kwatra ◽  
Bidya Dhar Sahu ◽  
VGM Naidu
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Free Radicals ◽  
Nlrp3 Inflammasome ◽  
Nuclear Translocation ◽  
Inflammasome Activation ◽  
Mitochondrial Ros ◽  
Nlrp3 Inflammasome Activation

Abstract Several activators of NLRP3 inflammasome have been described; however, the central mechanisms of NLRP3 inflammasome activation in brain microglia, especially at the activating step through free radical generation, still require further clarification. Hence the present study aimed to investigate the role of free radicals in activating NLRP3 inflammasome driven neurodegeneration and elucidated the neuroprotective role of perillyl alcohol (PA) in vitro and in vivo models of Parkinson’s disease. Initial priming of microglial cells with lipopolysaccharide (LPS) following treatment with hydrogen peroxide (H2O2) induces NF-κB translocation to nucleus with robust generation of free radicals that act as Signal 2 in augmenting NLRP3 inflammasome assembly and its downstream targets. PA treatment suppresses nuclear translocation of NF-κB and maintains cellular redox homeostasis in microglia that limits NLRP3 inflammasome activation along with processing active caspase-1, IL-1β and IL-18. To further correlates the in vitro study with in vivo MPTP model, treatment with PA also inhibits the nuclear translocation of NF-κB and downregulates the NLRP3 inflammasome activation. PA administration upregulates various antioxidant enzymes levels and restored the level of dopamine and other neurotransmitters in the striatum of the mice brain with improved behavioural activities. Additionally, treatment with Mito-TEMPO (a mitochondrial ROS inhibitor) was also seen to inhibit NLRP3 inflammasome and rescue dopaminergic neuron loss in the mice brain. Therefore, we conclude that NLRP3 inflammasome activation requires a signal from damaged mitochondria for its activation. Further pharmacological scavenging of free radicals restricts microglia activation and simultaneously supports neuronal survival via targeting NLRP3 inflammasome pathway in Parkinson’s disease.

Abstract P259: Endothelial Acid Sphingomyelinase Gene Determines Inflammasome Activation and Atherosclerotic Lesions in Carotid Arteries During Hypercholesterolemia

Hypertension ◽  
2015 ◽  
Vol 66 (suppl_1) ◽  
Author(s):  
Min Xia ◽  
Krishna M Bioni ◽  
Yang Chen ◽  
Xiang Li ◽  
Ashley L Pitzer ◽  
...  
Keyword(s):  
Carotid Arteries ◽  
Acid Sphingomyelinase ◽  
Receptor Protein ◽  
Inflammasome Activation ◽  
Neointimal Formation ◽  
Atherosclerotic Lesions ◽  
Junction Protein ◽  
Nlrp3 Inflammasomes

Nucleotide oligomerization domain (NOD)-like receptor protein with pyrin domain containing 3 (Nlrp3) inflammasome has been reported to be activated by atherogenic factors, thereby triggering endothelial injury and consequent atherosclerotic lesions in the arterial wall. However, the mechanism activating and regulating Nlrp3 inflammasomes remains poorly understood. The present study tested whether membrane raft (MR) signaling platforms associated with acid sphingomyelinase (ASM) and its product ceramide (Ce) importantly contribute to the activation of Nlrp3 inflammasomes and atherosclerotic lesions during hypercholesterolemia (HC). By confocal microscopy and biochemical analyses, we demonstrated the formation and activation of Nlrp3 inflammasomes in the intima of the carotid arteries of Asm +/+ mice with HC (as shown by a 2-fold increase in caspase-1 activity and a 6-fold enhancement of IL-1β positive stain areas), but not in Asm -/- mice. In endothelium-specific ASM transgenic mice (EC-Asm trg ), this inflammasome formation and activation were enhanced. Correspondingly, HC-induced increases in IL-1β production, ASM expression, Ce level and MR-gp91 phox clustering in the carotid intima were abolished in Asm -/- mice, but enhanced in EC-Asm trg mice. Functionally, endothelium-dependent vasodilation (EDVD) in carotid arteries in vivo (by ultrasound flowmetry) and in vitro (in perfused artery) was impaired by HC in Asm +/+ mice by 33% and 54%, respectively. This endothelial dysfunction was not observed in Asm -/- mice. The endothelial tight junction protein, ZO-1 was reduced by HC in both Asm +/+ and EC-Asm trg mice, but not in Asm -/- mice. It was also found that HC-increased neointimal formation, T-cell infiltration, and fibrosis in 2-week partially ligated carotid arteries (PLCA) occurred in Asm +/+ mice, but not in Asm -/- mice with HC. EC-Asm trg mice even exhibited more severe inflammatory and atherosclerotic lesions. All these results suggest that Asm gene and related MR clustering are essential to endothelial inflammasome activation and dysfunction in carotid arteries, ultimately determining the extent of atherosclerotic lesions.

Sign in / Sign up

Export Citation Format

Share Document