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1.
Adv Exp Med Biol ; 1209: 109-123, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31728867

RESUMO

Inflammasome is a molecular platform that mediates the activation of caspases, maturation of interleukin-1 (IL-1) family members, and leads to inflammatory cell death called pyroptosis. It is vital for innate immune responses, providing protection against infectious agents, sterile environmental insults, and host cell damages. Aberrant activation of inflammasome is closely correlated with numerous hereditary and acquired inflammatory disorders. Therefore, a better understanding of how inflammasome is regulated may provide more promising therapeutics for controlling inflammasome-associated diseases. In recent years, it becomes apparent that autophagy, a cellular machinery essential for the recycling of intracellular components and maintenance of cellular homeostasis, acts as a key player in the activation and regulation of inflammasome, and ameliorates symptoms of inflammasome-related diseases. This review will discuss the recent insights into inflammasome activation and regulation mediated by autophagy.


Assuntos
Autofagia , Inflamassomos , Autofagia/imunologia , Caspases/metabolismo , Ativação Enzimática , Humanos , Imunidade Inata/imunologia , Inflamassomos/imunologia , Interleucina-1/imunologia , Piroptose/imunologia
2.
Adv Exp Med Biol ; 1172: 119-141, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31628654

RESUMO

The nucleotide-binding domain (NBD) and leucine-rich repeat (LRR) containing (NLR) proteins are a large family of intracellular immune receptors conserved in both animals and plants. Mammalian NLRs function as pattern recognition receptors (PRRs) to sense pathogen-associated molecular patterns (PAMPs) or host-derived danger associated molecular patterns (DAMPs). PAMP or DAMP perception activates NLRs which consequently recruit pro-caspase-1 directly or indirectly. These sequential events result in formation of large multimeric protein complexes termed inflammasomes that mediate caspase-1 activation for pyroptosis and cytokine secretion. Recent structural and biochemical studies provide significant insights into the acting mechanisms of NLR proteins. In this chapter, we review and discuss these studies concerning autoinhibition, ligand recognition, activation of NLRs, and assembly of NLR inflammasomes.


Assuntos
Inflamassomos , Proteínas NLR , Animais , Inflamassomos/biossíntese , Inflamassomos/imunologia , Proteínas NLR/química , Proteínas NLR/imunologia , Plantas , Receptores de Reconhecimento de Padrão
3.
Adv Exp Med Biol ; 1172: 143-155, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31628655

RESUMO

AIM2 (absent in melanoma 2) is a cytoplasmic sensor of double-stranded DNA from pathogens or damaged cellular organelles. It recruits ASC (apoptosis-associated specklike protein containing a CARD) and caspase-1 to form the AIM2 inflammasome, activate caspase-1, and elicit inflammatory responses via cytokine maturation and pyroptotic cell death. Structural studies from X-ray crystallography, NMR, and cryo-EM have revealed many details in AIM2 inflammasome activation, assembly, and regulation. Many principles learned from AIM2 inflammasome also apply to other inflammasomes. In this chapter, we discuss the interactions between dsDNA and AIM2-like receptors, between AIM2 and adaptor protein ASC, and between ASC and caspase-1 with the focus on helical filament assembly formed by PYD and CARD domains.


Assuntos
Proteínas de Ligação a DNA , Inflamassomos , Transdução de Sinais , Animais , Caspase 1 , DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Humanos , Inflamassomos/biossíntese , Inflamassomos/imunologia , Ligação Proteica
4.
EMBO J ; 38(20): e101266, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31544965

RESUMO

Inflammasomes are cytosolic protein complexes, which orchestrate the maturation of active IL-1ß by proteolytic cleavage via caspase-1. Although many principles of inflammasome activation have been described, mechanisms that limit inflammasome-dependent immune responses remain poorly defined. Here, we show that the thiol-specific peroxidase peroxiredoxin-4 (Prdx4) directly regulates IL-1ß generation by interfering with caspase-1 activity. We demonstrate that caspase-1 and Prdx4 form a redox-sensitive regulatory complex via caspase-1 cysteine 397 that leads to caspase-1 sequestration and inactivation. Mice lacking Prdx4 show an increased susceptibility to LPS-induced septic shock. This effect was phenocopied in mice carrying a conditional deletion of Prdx4 in the myeloid lineage (Prdx4-ΔLysMCre). Strikingly, we demonstrate that Prdx4 co-localizes with inflammasome components in extracellular vesicles (EVs) from inflammasome-activated macrophages. Purified EVs are able to transmit a robust IL-1ß-dependent inflammatory response in vitro and also in recipient mice in vivo. Loss of Prdx4 boosts the pro-inflammatory potential of EVs. These findings identify Prdx4 as a critical regulator of inflammasome activity and provide new insights into remote cell-to-cell communication function of inflammasomes via macrophage-derived EVs.


Assuntos
Caspase 1/metabolismo , Vesículas Extracelulares/metabolismo , Inflamassomos/imunologia , Macrófagos/imunologia , Peroxirredoxinas/fisiologia , Choque Séptico/prevenção & controle , Animais , Caspase 1/genética , Citocinas/metabolismo , Feminino , Inflamassomos/metabolismo , Lipopolissacarídeos/toxicidade , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Choque Séptico/induzido quimicamente , Choque Séptico/imunologia , Choque Séptico/patologia , Transdução de Sinais
5.
BMC Complement Altern Med ; 19(1): 216, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31412862

RESUMO

BACKGROUND: Breast cancer is still the most common malignant tumor that threatens the female's life in the world, especially triple-negative breast cancer (TNBC), one of the most difficult subtypes. Lack of targeted therapies brings about urgent demand for novel treatments. In this study we aim to investigate the anti-tumor activity of Berberine (BBR), a Chinese plant-derived alkaloid, against the TNBC cell line MDA-MB-231 and elucidate its mechanism referring to anti-inflammation. METHODS: Cell inhibition rate was measured by Cell Proliferation Assay, the cytotoxic effects was detected by Lactate dehydrogenase (LDH) leakage assay, the colony formation and migration potential were evaluated by colony formation assay and wound healing assay, the release of inflammatory cytokines was detected by EMD multifactor detection, and alterations of proteins and genes related to the NLR family pyrin domain containing 3 (NLRP3) inflammasome pathway were analyzed using western blotting and real-time Polymerase Chain Reaction (PCR). RESULTS: BBR reduce the viability of MDA-MB-231 cells and increased the release of LDH from the cells in a dose-dependent manner, with and inhibition of colony formation potential and migration of the cells. BBR also caused a marked reduction in the secretion of proinflammatory cytokines, Interleukin-1α (IL-1α), Interleukin-1ß (IL-1ß), Interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). Besides, a down-regulated behavior was observed with the expression of P2X purinoceptor 7 (P2X7), NLRP3, pro-caspase-1, apoptosis-associated speck-like protein containing a caspase-activation and recruitment domain (ASC), caspase-1 p20, Interleukin-18 (IL-18), IL-1ß proteins and NLRP3, Caspase-1 and ASC mRNAs in the NLRP3 inflammasome cascade. CONCLUSIONS: Our results confirmed that BBR can effectively affect both tumor outgrowth and spontaneous metastasis in TNBC, and that we identified a new mechanism associated with inhibition the NLRP3 inflammasome pathway, suggesting its potential therapeutic relevance in clinical use.


Assuntos
Berberina/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Inflamassomos/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Neoplasias de Mama Triplo Negativas/imunologia , Apoptose/efeitos dos fármacos , Caspase 1/genética , Caspase 1/imunologia , Feminino , Humanos , Inflamassomos/genética , Inflamassomos/imunologia , Interleucina-18/genética , Interleucina-18/imunologia , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/fisiopatologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
6.
Cell Physiol Biochem ; 53(2): 355-365, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31385664

RESUMO

BACKGROUND/AIMS: NLRP3 inflammasome activation has been reported to be an early mechanism responsible for glomerular inflammation and injury in obese mice. However, the precise mechanism of obesity-induced NLRP3 inflammasome activation remains unknown. The present study explored whether adipokine visfatin mediates obesity-induced NLRP3 inflammasome activation and consequent podocyte injury. METHODS: Inflammasome formation and immunofluorescence expressions were quantified by confocal microscopy. Caspase-activity, IL-1ß production and VEGF concentrations were measured by ELISA. RESULTS: Confocal microscopic analysis showed that visfatin treatment increased the colocalization of Nlrp3 with Asc or Nlrp3 with caspase-1 in podocytes indicating the formation of NLRP3 inflammasomes. This visfatin-induced NLRP3 inflammasome formation was abolished by pretreatment of podocytes with Asc siRNA. Correspondingly, visfatin treatment significantly increased the caspase-1 activity and IL-1ß production in podocytes, which was significantly attenuated by Asc siRNA transfection. Further RT-PCR and confocal microscopic analysis demonstrated that visfatin treatment significantly decreased the podocin expression (podocyte damage). Podocytes pretreatment with Asc siRNA or caspase-1 inhibitor, WEHD attenuated this visfatin-induced podocin reduction. Furthermore, Asc siRNA transfection was found to preserve podocyte morphology by maintaining the distinct arrangement of F-actin fibers normally lost in response to visfatin. It also prevented podocyte dysfunction by restoring visfatin-induced suppression of VEGF production and secretion. CONCLUSION: Visfatin induces NLRP3 inflammasome activation in podocytes and thereby resulting in podocyte injury.


Assuntos
Adipocinas/imunologia , Inflamassomos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Nicotinamida Fosforribosiltransferase/imunologia , Podócitos/imunologia , Animais , Linhagem Celular , Inflamação/imunologia , Inflamação/patologia , Interleucina-1beta/imunologia , Camundongos , Obesidade/imunologia , Obesidade/patologia , Podócitos/citologia , Podócitos/patologia , Fator A de Crescimento do Endotélio Vascular/imunologia
7.
Immunology ; 158(3): 240-251, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31429483

RESUMO

The clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated systems (CRISPR-Cas) systems in prokaryotes function at defending against foreign DNAs, providing adaptive immunity to maintain homeostasis. CRISPR-Cas may also influence immune regulation ability in mammalian cells through alterations of pathogenic extent and nature. Recent research has implied that Type I CRISPR-Cas systems of Pseudomonas aeruginosa strain UCBPP-PA14 impede recognition by Toll-like receptor 4, and decrease pro-inflammatory responses both in vitro and in vivo. However, the molecular mechanism by which CRISPR-Cas systems affect host immunity is largely undemonstrated. Here, we explored whether CRISPR-Cas systems can influence autophagy to alter the activation of inflammasome. Using the wild-type PA14 and total CRISPR-Cas region deletion (∆TCR) mutant strain, we elucidated the role and underlying mechanism of Type I CRISPR-Cas systems in bacterial infection, and showed that CRISPR-Cas systems impacted the release of mitochondrial DNA and induction of autophagy. CRISPR-Cas deficiency led to an increase of mitochondrial DNA release, a decrease in autophagy, an increase of inflammasome activation and, ultimately, an elevation of pro-inflammatory response. Our findings illustrate a new important mechanism by which Type I CRISPR-Cas systems control their virulence potency to evade host defense.


Assuntos
/imunologia , Sistemas CRISPR-Cas/imunologia , Evasão da Resposta Imune , Inflamassomos/imunologia , Infecções por Pseudomonas/imunologia , Pseudomonas aeruginosa , Animais , Linhagem Celular , Feminino , Masculino , Camundongos , Infecções por Pseudomonas/patologia , Pseudomonas aeruginosa/imunologia , Pseudomonas aeruginosa/patogenicidade
8.
Life Sci ; 234: 116773, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31422095

RESUMO

AIMS: NLRP3 inflammasome activation is essential for the development and prognosis of diabetic cardiomyopathy (DCM). The anti-aging protein Klotho is suggested to modulate tissue inflammatory responses. The aim of the present study was to examine the protective effects of Klotho on DCM. MAIN METHODS: A streptozotocin-induced diabetes mouse model was established to assess the effects of Klotho in vivo, which was administered for 12 weeks. The characteristics of type 1 DCM were evaluated by general status, echocardiography, and histopathology. The expression of associated factors was determined by RT-qPCR and western blotting. Parallel experiments to determine the molecular mechanism through which Klotho prevents DCM were performed using H9C2 cells exposed to high glucose (35 mM). KEY FINDINGS: Diabetes-induced increases in serum creatine kinase-muscle/brain and lactate dehydrogenase levels, cardiac fibrosis, cardiomyocyte apoptosis, and cardiac dysfunction were ameliorated by Klotho. Additionally, Klotho suppressed TXNIP expression, NLRP3 inflammasome activation, and expression of the inflammatory cytokines tumor necrosis factor ɑ, interleukin-1ß, and interleukin-18 in vivo. In high glucose-cultured cardiomyocytes, Klotho and N-acetylcysteine significantly downregulated intracellular reactive oxygen species generation and TXNIP/NLRP3 inflammasome activation. Pretreatment of H9C2 cells with NLRP3 siRNA or Klotho prevented high glucose-induced inflammation and apoptosis in H9C2 cells. SIGNIFICANCE: Our results demonstrate that the protective effect of Klotho on diabetes-induced cardiac injury is associated with inhibition of the NLRP3 inflammasome pathway, suggesting its therapeutic potential for DCM.


Assuntos
Diabetes Mellitus Experimental/imunologia , Cardiomiopatias Diabéticas/imunologia , Glucuronidase/imunologia , Inflamassomos/imunologia , Inflamação/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Animais , Anti-Inflamatórios/imunologia , Anti-Inflamatórios/uso terapêutico , Cardiotônicos/imunologia , Cardiotônicos/uso terapêutico , Linhagem Celular , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/patologia , Cardiomiopatias Diabéticas/tratamento farmacológico , Cardiomiopatias Diabéticas/etiologia , Cardiomiopatias Diabéticas/patologia , Glucuronidase/uso terapêutico , Inflamação/tratamento farmacológico , Inflamação/etiologia , Inflamação/patologia , Masculino , Camundongos Endogâmicos C57BL , Ratos , Espécies Reativas de Oxigênio/imunologia
9.
EMBO J ; 38(21): e101365, 2019 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-31468569

RESUMO

Inflammasomes are potent innate immune signalling complexes that couple cytokine release with pro-inflammatory cell death. However, pathogens have evolved strategies to evade this cell autonomous system. Here, we show how antibodies combine with innate sensors in primary human macrophages to detect viral infection and activate the inflammasome. Our data demonstrate that antibody opsonisation of virions can activate macrophages in multiple ways. In the first, antibody binding of adenovirus causes lysosomal damage, activating NLRP3 to drive inflammasome formation and IL-1ß release. Importantly, this mechanism enhances virion capture but not infection and is accompanied by cell death, denying the opportunity for viral replication. Unexpectedly, we also find that antibody-coated viruses, which successfully escape into the cytosol, trigger a second system of inflammasome activation. These viruses are intercepted by the cytosolic antibody receptor TRIM21 and the DNA sensor cGAS. Together, these sensors stimulate both NLRP3 inflammasome formation and NFκB activation, driving dose-dependent IL-1ß and TNF secretion, without inducing cell death. Our data highlight the importance of cooperativity between multiple sensing networks to expose viruses to the inflammasome pathway, which is particularly important for how our innate immune system responds to infection in the presence of pre-existing immunity.


Assuntos
Infecções por Adenoviridae/imunologia , Anticorpos Antivirais/imunologia , Inflamassomos/imunologia , Macrófagos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Nucleotidiltransferases/metabolismo , Ribonucleoproteínas/metabolismo , Replicação Viral/imunologia , Adenoviridae/genética , Adenoviridae/imunologia , Infecções por Adenoviridae/metabolismo , Infecções por Adenoviridae/virologia , Animais , Células Cultivadas , Humanos , Inflamassomos/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Macrófagos/virologia , Camundongos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Nucleotidiltransferases/genética , Ribonucleoproteínas/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
10.
Mar Drugs ; 17(8)2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31374828

RESUMO

Excessive exposure to ultraviolet (UV) radiation is the main risk factor to develop skin pathologies or cancer because it encourages oxidative condition and skin inflammation. In this sense, strategies for its prevention are currently being evaluated. Natural products such as carotenoids or polyphenols, which are abundant in the marine environment, have been used in the prevention of oxidative stress due to their demonstrated antioxidant activities. Nevertheless, the anti-inflammatory activity and its implication in photo-prevention have not been extensively studied. Thus, we aimed to evaluate the combination of fucoxanthin (FX) and rosmarinic acid (RA) on cell viability, apoptosis induction, inflammasome regulation, and anti-oxidative response activation in UVB-irradiated HaCaT keratinocytes. We demonstrated for the first time that the combination of FX and RA (5 µM RA plus 5 µM FX, designated as M2) improved antioxidant and anti-inflammatory profiles in comparison to compounds assayed individually, by reducing UVB-induced apoptosis and the consequent ROS production. Furthermore, the M2 combination modulated the inflammatory response through down-regulation of inflammasome components such as NLRP3, ASC, and Caspase-1, and the interleukin (IL)-1ß production. In addition, Nrf2 and HO-1 antioxidant genes expression increased in UVB-exposed HaCaT cells pre-treated with M2. These results suggest that this combination of natural products exerts photo-protective effects by down-regulating NRLP3-inflammasome and increasing Nrf2 signalling pathway.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Cinamatos/farmacologia , Depsídeos/farmacologia , Envelhecimento da Pele/efeitos dos fármacos , Xantofilas/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Sinergismo Farmacológico , Humanos , Inflamassomos/efeitos dos fármacos , Inflamassomos/imunologia , Inflamassomos/metabolismo , Queratinócitos/efeitos dos fármacos , Queratinócitos/imunologia , Queratinócitos/efeitos da radiação , Fator 2 Relacionado a NF-E2/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Transdução de Sinais/efeitos da radiação , Pele/citologia , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Envelhecimento da Pele/efeitos da radiação , Raios Ultravioleta/efeitos adversos
11.
Nat Commun ; 10(1): 3493, 2019 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375698

RESUMO

Hydrogen peroxide (H2O2) has a major function in host-microbial interactions. Although most studies have focused on the endogenous H2O2 produced by immune cells to kill microbes, bacteria can also produce H2O2. How microbial H2O2 influences the dynamics of host-microbial interactions is unclear. Here we show that H2O2 released by Streptococcus pneumoniae inhibits inflammasomes, key components of the innate immune system, contributing to the pathogen colonization of the host. We also show that the oral commensal H2O2-producing bacteria Streptococcus oralis can block inflammasome activation. This study uncovers an unexpected role of H2O2 in immune suppression and demonstrates how, through this mechanism, bacteria might restrain the immune system to co-exist with the host.


Assuntos
Coinfecção/imunologia , Peróxido de Hidrogênio/metabolismo , Tolerância Imunológica , Imunidade Inata , Inflamassomos/imunologia , Animais , Proteínas Adaptadoras de Sinalização CARD/genética , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Coinfecção/microbiologia , Modelos Animais de Doenças , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Peróxido de Hidrogênio/imunologia , Inflamassomos/metabolismo , Camundongos , Camundongos Knockout , Streptococcus oralis/imunologia , Streptococcus oralis/metabolismo , Streptococcus oralis/patogenicidade , Streptococcus pneumoniae/imunologia , Streptococcus pneumoniae/metabolismo , Streptococcus pneumoniae/patogenicidade
12.
Mol Immunol ; 114: 41-48, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31336248

RESUMO

Viral myocarditis, mainly caused by enteroviruses specially coxsackievirus B3 (CVB3) infection, is a common clinical cardiovascular disease and characterized by cardiac massive inflammation. Our previous study showed that CVB3-induced myocardial NLRP3 contributed to the development of viral myocarditis. In this study, we found that beside of being up-regulated in myocardiocytes, NLPR3 was also obviously increased in the cardiac infiltrating macrophages. While whether this accumulated NLRP3 influences, macrophage inflammatory responses remains unknown. By adoptive transfer assays, we found that mice receiving NLRP3 up-regulated macrophages showed much more abundant cardiac IL-1ß production and more severe myocardial inflammation, while those receiving NLRP3 down-regulated macrophages showed much less IL-1ß production and milder myocarditis, indicating that NLRP3 up-regulated macrophages played a pathological role in CVB3-induced myocarditis. In addition, we further found that it was CVB3 capsid proteins VP1 (predominant) and VP2, but not viral RNAs, robustly triggered macrophage NLRP3 up-regulation and activation. Our study demonstrated macrophage NLRP3 inflammasome could be efficiently be activated by CVB3 capsid proteins, and contributed to the pathogenesis of viral myocarditis. It might provide some clues to the development of new therapeutic strategies based on macrophage NLRP3 modulation.


Assuntos
Proteínas do Capsídeo/imunologia , Infecções por Coxsackievirus/imunologia , Enterovirus/imunologia , Inflamassomos/imunologia , Macrófagos/imunologia , Miocardite/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Transferência Adotiva/métodos , Animais , Linhagem Celular , Linhagem Celular Tumoral , Regulação para Baixo/imunologia , Células HeLa , Coração/virologia , Humanos , Inflamação/imunologia , Macrófagos/virologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Miocardite/virologia , Miocárdio/imunologia , Células RAW 264.7 , Regulação para Cima/imunologia , Viroses/imunologia , Viroses/virologia
13.
Vet Res ; 50(1): 53, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300043

RESUMO

Our previous studies demonstrated that matrine directly acts on the replication process of porcine reproductive and respiratory syndrome virus (PRRSV). Matrine inhibits viral replication and is also associated with the NF-κB signalling pathway. These results suggest that matrine has antiviral and anti-inflammatory effects. However, the specific anti-inflammatory mechanism of matrine is still unclear. In this study, we investigated the anti-IL-1ß mechanism of matrine, as IL-1ß is a major inflammatory cytokine, in porcine alveolar macrophages (PAMs) stimulated with 4 µg PRRSV 5'-untranslated region (UTR) RNA and 1 µg/mL LPS. After 5'UTR RNA and LPS co-stimulation of PAMs for 12 h, the expression of IL-1ß, IL-6, IL-8 and TNF-α was significantly increased. The results also showed that co-stimulation induced the expression of MyD88, and activated the NF-κB signalling pathway and NLRP3 inflammasome. Furthermore, matrine treatment downregulated MyD88, NLRP3 and caspase-1 expression, inhibited ASC speck formation, suppressed IκBα phosphorylation, and interfered with the translocation of NF-κB from the cytoplasm to the nucleus. These results suggest that matrine plays an important role in PAMs co-stimulated with PRRSV 5'UTR RNA and LPS via its effect on NF-κB and the NLRP3 inflammasome. These findings lay the foundation for the exploration of the clinical application of matrine in PRRSV disease.


Assuntos
Alcaloides/farmacologia , Inflamassomos/imunologia , Interleucina-1beta/metabolismo , Macrófagos/efeitos dos fármacos , NF-kappa B/imunologia , Quinolizinas/farmacologia , Animais , Lipopolissacarídeos/farmacologia , Macrófagos/imunologia , Fator 88 de Diferenciação Mieloide/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , RNA Viral/genética , Transdução de Sinais/imunologia , Sus scrofa , Transfecção/veterinária
14.
J Food Sci ; 84(7): 1920-1928, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31264720

RESUMO

Vanillin, a kind of phenolic compound, is naturally found in food and beverage and widely used as a flavoring agent. In view of the safety and universality of vanillin, exploring the functions of vanillin on human is of great value. Thus, lipopolysaccharide (LPS)-activated THP-1 cells were selected as the cell model to evaluate the anti-inflammatory effect of vanillin in this study. On the basis of the results, vanillin markedly suppressed the expression of inflammatory cytokines (that is, TNF-α, IL-1ß, IL-6, and IL-8), mediators (NO, iNOS, PGE2, and COX-2), and NLRP3 inflammasome (that is, NLRP3, ASC, and caspase-1), blocked the LPS-induced activation of the NF-κB/IκBα/AP-1 signaling pathway, and activated the gene expression of the Nrf2/HO-1 signaling pathway. In addition, it was confirmed that vanillin was unable to react with LPS due to the results of quantification by HS-SPME-GC-MS. Hence, vanillin could effectively attenuate LPS-induced inflammatory response by regulating the expression of intracellular signaling pathways in THP-1 cells. It is a potent anti-inflammatory component found in food and beverage. These findings might contribute to the overall understanding of the potential health benefits of vanillin for food application. PRACTICAL APPLICATION: In this study, the anti-inflammatory effect of vanillin (VA) was evaluated by ELISA, real-time PCR, and western blot in LPS-induced THP-1 cells. The hypothesis that VA could react with LPS was excluded due to the results of quantification by HS-SPME-GC-MS. On the basis of the result, vanillin could effectively attenuate LPS-induced inflammatory response in THP-1 cells and was a potent anti-inflammatory component natural in food and beverage. These findings might contribute to the overall understanding of the potential health benefits of vanillin for food application.


Assuntos
Anti-Inflamatórios/farmacologia , Benzaldeídos/farmacologia , Lipopolissacarídeos/farmacologia , Monócitos/efeitos dos fármacos , Ciclo-Oxigenase 2/imunologia , Humanos , Inflamassomos/efeitos dos fármacos , Inflamassomos/imunologia , Interleucina-1beta/imunologia , Lipopolissacarídeos/imunologia , Monócitos/imunologia , Fator 2 Relacionado a NF-E2/imunologia , NF-kappa B/imunologia , Óxido Nítrico Sintase Tipo II/imunologia , Células THP-1
15.
PLoS Pathog ; 15(6): e1007872, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31194844

RESUMO

Innate recognition of invading intracellular pathogens is essential for regulating robust and rapid CD4+ T cell effector function, which is critical for host-mediated immunity. The intracellular apicomplexan parasite, Toxoplasma gondii, is capable of infecting almost any nucleated cell of warm-blooded animals, including humans, and establishing tissue cysts that persist throughout the lifetime of the host. Recognition of T. gondii by TLRs is essential for robust IL-12 and IFN-γ production, two major cytokines involved in host resistance to the parasite. In the murine model of infection, robust IL-12 and IFN-γ production have been largely attributed to T. gondii profilin recognition by the TLR11 and TLR12 heterodimer complex, resulting in Myd88-dependent IL-12 production. However, TLR11 or TLR12 deficiency failed to recapitulate the acute susceptibility to T. gondii infection seen in Myd88-/- mice. T. gondii triggers inflammasome activation in a caspase-1-dependent manner resulting in cytokine release; however, it remains undetermined if parasite-mediated inflammasome activation impacts IFN-γ production and host resistance to the parasite. Using mice which lack different inflammasome components, we observed that the inflammasome played a limited role in host resistance when TLR11 remained functional. Strikingly, in the absence of TLR11, caspase-1 and -11 played a significant role for robust CD4+ TH1-derived IFN-γ responses and host survival. Moreover, we demonstrated that in the absence of TLR11, production of the caspase-1-dependent cytokine IL-18 was sufficient and necessary for CD4+ T cell-derived IFN-γ responses. Mechanistically, we established that T. gondii-mediated activation of the inflammasome and IL-18 were critical to maintain robust CD4+ TH1 IFN-γ responses during parasite infection in the absence of TLR11.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Imunidade Inata , Inflamassomos/imunologia , Interferon gama/imunologia , Receptores Toll-Like/imunologia , Toxoplasma/imunologia , Toxoplasmose Animal/imunologia , Animais , Linfócitos T CD4-Positivos/parasitologia , Linfócitos T CD4-Positivos/patologia , Caspase 1/genética , Caspase 1/imunologia , Caspases/genética , Caspases/imunologia , Inflamassomos/genética , Interferon gama/genética , Interleucina-18/genética , Interleucina-18/imunologia , Camundongos , Camundongos Knockout , Receptores Toll-Like/genética , Toxoplasmose Animal/genética , Toxoplasmose Animal/patologia
16.
PLoS Pathog ; 15(6): e1007795, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31170267

RESUMO

Infection with the Streptococcus suis (S. suis) epidemic strain can cause Streptococcal toxic shock-like syndrome (STSLS), which is characterized by a cytokine storm, dysfunction of multiple organs and a high incidence of mortality despite adequate treatment. Despite some progress concerning the contribution of the inflammatory response to STSLS, the precise mechanism underlying STSLS development remains elusive. Here, we use a murine model to demonstrate that caspase-1 activity is critical for STSLS development. Furthermore, we show that inflammasome activation by S. suis is mainly dependent on NLRP3 but not on NLRP1, AIM2 or NLRC4. The important role of NLRP3 activation in STSLS is further confirmed in vivo with the NLRP3 inhibitor MCC950 and nlrp3-knockout mice. By comparison of WT strain with isogenic strains with mutation of various virulence genes for inflammasome activation, Suilysin is essential for inflammasome activation, which is dependent on the membrane perforation activity to cause cytosolic K+ efflux. Moreover, the mutant strain msly (P353L) expressing mutagenic SLY without hemolytic activity was unable to activate the inflammasome and does not cause STSLS. In summary, we demonstrate that the high membrane perforation activity of the epidemic strain induces a high level of NLRP3 inflammasome activation, which is essential for the development of the cytokine storm and multi-organ dysfunction in STSLS and suggests NLRP3 inflammasome as an attractive target for the treatment of STSLS.


Assuntos
Citocinas/imunologia , Inflamassomos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Choque Séptico/imunologia , Infecções Estreptocócicas/imunologia , Streptococcus suis/imunologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/imunologia , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/imunologia , Citocinas/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Inflamassomos/genética , Camundongos , Camundongos Endogâmicos BALB C , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Choque Séptico/genética , Choque Séptico/patologia , Infecções Estreptocócicas/genética , Infecções Estreptocócicas/patologia
17.
J Neuroinflammation ; 16(1): 121, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31174550

RESUMO

The NLRP3 (nucleotide-binding oligomerization domain-like receptor [NLR] family pyrin domain-containing 3) inflammasome is a member of the NLR family of innate immune cell sensors. These are crucial regulators of cytokine secretions, which promote ischemic cell death and insulin resistance. This review summarizes recent progress regarding the NLRP3 inflammasome as a potential treatment for ischemic stroke in patients with diabetes, two complicated diseases that often occur together. Stroke worsens glucose metabolism abnormalities, and the outcomes after stroke are more serious for diabetic patients compared with those without diabetes. Inflammation contributes to organ injury after ischemic stroke and diabetes. Recent research has focused on inhibiting the activation of inflammasomes and thus reducing the maturation of proinflammatory cytokines such as interleukin (IL)-1ß and IL-18. Studies suggest that inhibition of NLRP3 prevents or alleviates both ischemic stroke and diabetes. Targeting against the assembly and activity of the NLRP3 inflammasome is a potential and novel therapy for inflammasome-associated diseases, including ischemic stroke concomitant with diabetes.


Assuntos
Isquemia Encefálica/metabolismo , Complicações do Diabetes/metabolismo , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Acidente Vascular Cerebral/metabolismo , Animais , Isquemia Encefálica/complicações , Isquemia Encefálica/imunologia , Complicações do Diabetes/imunologia , Diabetes Mellitus/imunologia , Diabetes Mellitus/metabolismo , Humanos , Inflamassomos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/imunologia
18.
Free Radic Res ; 53(7): 780-790, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31185753

RESUMO

Oxidative stress is a key mechanism underlying ozone-induced lung injury. Mitochondria can release mitochondrial reactive oxidative species (mtROS), which may lead to the activation of NLRP3 inflammasome. The goal of this study was to examine the roles of mtROS and NLRP3 inflammasome in acute ozone-induced airway inflammation and bronchial hyperresponsiveness (BHR). C57/BL6 mice (n = 8/group) were intraperitoneally treated with vehicle (phosphate buffered saline, PBS) or mitoTEMPO (mtROS inhibitor, 20 mg/kg), or orally treated with VX-765 (caspse-1 inhibitor, 100 mg/kg) 1 h before the ozone exposure (2.5 ppm, 3 h). Compared to the PBS-treated ozone-exposed mice, mitoTEMPO reduced the level of total malondialdehyde in bronchoalveolar lavage (BAL) fluid and increased the expression of mitochondrial complexes II and IV in the lung 24 h after single ozone exposure. VX-765 inhibited ozone-induced BHR, BAL total cells including neutrophils and eosinophils, and BAL inflammatory cytokines including IL-1α, IL-1ß, KC, and IL-6. Both mitoTEMPO and VX-765 reduced ozone-induced mtROS and inhibited capase-1 activity in lung tissue whilst VX-765 further inhibited DRP1 and MFF expression, increased MFN2 expression, and down-regulated caspase-1 expression in the lung tissue. These results indicate that acute ozone exposure induces mitochondrial dysfunction and NLRP3 inflammasome activation, while the latter has a critical role in the pathogenesis of ozone-induced airway inflammation and BHR.


Assuntos
Hiper-Reatividade Brônquica/metabolismo , Inflamassomos/metabolismo , Inflamação/metabolismo , Mitocôndrias/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Hiper-Reatividade Brônquica/imunologia , Modelos Animais de Doenças , Inflamassomos/imunologia , Inflamação/imunologia , Masculino , Camundongos , Mitocôndrias/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Espécies Reativas de Oxigênio/imunologia
19.
PLoS Pathog ; 15(6): e1007886, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31251782

RESUMO

Inflammasomes are cytosolic multi-protein complexes that detect infection or cellular damage and activate the Caspase-1 (CASP1) protease. The NAIP5/NLRC4 inflammasome detects bacterial flagellin and is essential for resistance to the flagellated intracellular bacterium Legionella pneumophila. The effectors required downstream of NAIP5/NLRC4 to restrict bacterial replication remain unclear. Upon NAIP5/NLRC4 activation, CASP1 cleaves and activates the pore-forming protein Gasdermin-D (GSDMD) and the effector caspase-7 (CASP7). However, Casp1-/- (and Casp1/11-/-) mice are only partially susceptible to L. pneumophila and do not phenocopy Nlrc4-/-mice, because NAIP5/NLRC4 also activates CASP8 for restriction of L. pneumophila infection. Here we show that CASP8 promotes the activation of CASP7 and that Casp7/1/11-/- and Casp8/1/11-/- mice recapitulate the full susceptibility of Nlrc4-/- mice. Gsdmd-/- mice exhibit only mild susceptibility to L. pneumophila, but Gsdmd-/-Casp7-/- mice are as susceptible as the Nlrc4-/- mice. These results demonstrate that GSDMD and CASP7 are the key substrates downstream of NAIP5/NLRC4/CASP1/8 required for resistance to L. pneumophila.


Assuntos
Proteínas Reguladoras de Apoptose/imunologia , Proteínas de Ligação ao Cálcio/imunologia , Caspase 1/imunologia , Caspase 7/imunologia , Caspase 8/imunologia , Inflamassomos/imunologia , Legionella pneumophila/imunologia , Doença dos Legionários/imunologia , Proteína Inibidora de Apoptose Neuronal/imunologia , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas de Ligação ao Cálcio/genética , Caspase 1/genética , Caspase 7/genética , Caspase 8/genética , Inflamassomos/genética , Doença dos Legionários/genética , Doença dos Legionários/patologia , Camundongos , Camundongos Knockout , Proteína Inibidora de Apoptose Neuronal/genética
20.
Nat Commun ; 10(1): 2711, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221993

RESUMO

Sepsis is characterized by a systemic inflammatory response followed by immunosuppression of the host. Metabolic defects and mitochondrial failure are common in immunocompromised patients with sepsis. The NLRP3 inflammasome is important for establishing an inflammatory response after activation by the purinergic P2X7 receptor. Here, we study a cohort of individuals with intra-abdominal origin sepsis and show that patient monocytes have impaired NLRP3 activation by the P2X7 receptor. Furthermore, most sepsis-related deaths are among patients whose NLRP3 activation is profoundly altered. In monocytes from sepsis patients, the P2X7 receptor is associated with mitochondrial dysfunction. Furthermore, activation of the P2X7 receptor results in mitochondrial damage, which in turn inhibits NLRP3 activation by HIF-1α. We show that mortality increases in a mouse model of sepsis when the P2X7 receptor is activated in vivo. These data reveal a molecular mechanism initiated by the P2X7 receptor that contributes to NLRP3 impairment during infection.


Assuntos
Inflamassomos/imunologia , Monócitos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Sepse/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Modelos Animais de Doenças , Feminino , Seguimentos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/imunologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Inflamassomos/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Mitocôndrias/imunologia , Mitocôndrias/metabolismo , Dinâmica Mitocondrial/imunologia , Monócitos/citologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Receptores Purinérgicos P2X7/imunologia , Sepse/sangue , Sepse/microbiologia , Sepse/mortalidade , Regulação para Cima/imunologia
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