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1.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(2): 229-234, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-33829696

RESUMO

Objective: To investigate the effects of morin-regulated NLRP3/Caspase-1 pathway on experimental autoimmune thyroiditis in rats. Methods: The rats were randomly assigned to 6 groups: control group, experimental autoimmune thyroiditis group (EAT), low-, medium- and high-dose morin groups (post-modeling gavage of 50, 100 and 200 mg/kg morin hydrate per day for 6 weeks) and tripterygium wilfordii polyglycosides group (LGT group, post-modeling gavage of 6.25 mg/kg tripterygium wilfordii polyglycosidesper day for 6 weeks). Except for the control group, the rat model of experimental autoimmune thyroiditis was established by subcutaneous injection of 0.1 mL incomplete Freund's adjuvant containing porcine thyroglobulin. The levels of serum thyroglobulin (TgAb), thyroid peroxidase antibody (TPOAb), triiodothyronine (T3) and tetraiodothyronine (T4) in serum were detected by radioimmunoassay. The mRNA levels of interleukin-17 ( IL-17), interleukin-4 ( IL-4) and interferon γ ( INF- γ) were detected by reverse transcription-polymerase chain reaction. The levels of serum protein carbonyl content, 8-hydroxydeoxyguanosine (8-OHdG), and malondialdehyde (MDA) activity were checked with test kits. Expressions of NLRP3, apoptosis-related speck-like protein (ASC), and Caspase-1 were detected by Western blot. Results: Compared with the EAT group, serum levels of TPOAb, TgAb, T3, and T4 in low-, medium- and high-dose Morin groups and LGT group were reduced ( P<0.01) and the mRNA levels of IL-17, INF-γ and IL-4 were increased ( P<0.01), the protein hydroxyl content, MDA activity, and 8-OHdG levels were reduced ( P<0.01). The levels of NLRP3, ASC and Caspase-1 were reduced ( P<0.01), the levels of 8-OHdG were significantly reduced ( P<0.01), and the levels of NLRP3, ASC and Caspase-1 were significantly reduced ( P<0.01). There were statistically significant differences between the data from the low-dose and the medium-dose Morin groups and the data of the LGT group ( P<0.05), while data from the high-dose Morin group showed no significant difference compared with the data of the LGT group. Data from low-, medium- and high-dose Morin groups showed no statistically significant differences ( P<0.05). Conclusion: The findings suggest that Morin improved experimental autoimmune thyroiditis in rats through regulating NLRP3/Caspase-1 pathway.


Assuntos
Tireoidite Autoimune , Animais , Caspase 1/genética , Caspase 1/metabolismo , Flavonoides , Interleucina-1beta/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Carbonilação Proteica , Ratos , Suínos
2.
Science ; 371(6535)2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33542150

RESUMO

HIV-1 has high mutation rates and exists as mutant swarms within the host. Rapid evolution of HIV-1 allows the virus to outpace the host immune system, leading to viral persistence. Approaches to targeting immutable components are needed to clear HIV-1 infection. Here, we report that the caspase recruitment domain-containing protein 8 (CARD8) inflammasome senses HIV-1 protease activity. HIV-1 can evade CARD8 sensing because its protease remains inactive in infected cells before viral budding. Premature intracellular activation of the viral protease triggered CARD8 inflammasome-mediated pyroptosis of HIV-1-infected cells. This strategy led to the clearance of latent HIV-1 in patient CD4+ T cells after viral reactivation. Thus, our study identifies CARD8 as an inflammasome sensor of HIV-1, which holds promise as a strategy for the clearance of persistent HIV-1 infection.


Assuntos
Proteínas Adaptadoras de Sinalização CARD/metabolismo , Infecções por HIV/virologia , Protease de HIV/metabolismo , HIV-1/fisiologia , Inflamassomos/metabolismo , Proteínas de Neoplasias/metabolismo , Piroptose , Alquinos/farmacologia , Fármacos Anti-HIV/farmacologia , Benzoxazinas/farmacologia , Proteínas Adaptadoras de Sinalização CARD/química , Linfócitos T CD4-Positivos/fisiologia , Linfócitos T CD4-Positivos/virologia , Caspase 1/metabolismo , Ciclopropanos/farmacologia , Ativação Enzimática , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Humanos , Macrófagos/fisiologia , Macrófagos/virologia , Proteínas de Neoplasias/química , Inibidores da Transcriptase Reversa/farmacologia , Rilpivirina/farmacologia , Células THP-1 , Latência Viral
3.
Life Sci ; 270: 119123, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33548287

RESUMO

Chronic ulceration of the colon is associated with the activation of TLR4/NF-κB and P2X7R/NLRP3 signaling pathways. We investigated the effect of individual or combined administration of BBG, a P2X7R blocker, and OLT1177, a selective NLRP3 inhibitor, in the dextran sodium sulfate-induced ulcerative colitis (UC) rat model. The ulcerative rats were treated orally with brilliant blue G (BBG) (50 mg/kg/day) or OLT1177 (200 mg/kg/day) or a combination of both. Myd88 and NF-κB levels were measured by ELISA, qRT-PCR, and immunohistochemical staining. Cytokines known to be associated with TLR4/NF-κB or P2X7R/NLRP3 signaling were measured by ELISA. P2X7R and NLRP3 expression were measured by ELISA and qRT-PCR. The administration of BBG or OLT1177 ameliorated the toxic effects of DSS on the colon as they restored normal colonic macroscopic and microscopic morphology. BBG administration, but not OLT1177, reduced the expression of Myd88, NF-κB, IL-6, and TNF-α in addition to lowering P2X7R and oxidative stress levels. Individual BBG or OLT1177 administration decreased NLRP3 inflammasome recruitment and subsequent activation of caspase-1, IL-1ß, and IL-18. However, the combined administration of OLT1177 with BBG potentiated its inhibitory effect on the NLRP3, which was reflected by the additional suppressive effect on caspase-1, IL-1ß, IL-18 levels. In conclusion, BBG/OLT1177 exhibited complementary effects and effectively ameliorated UC. This novel approach provides a basis for the clinical application of this combination for the treatment of IBDs and might also be promising for the pharmacological intervention of other NLRP3 inflammasome-dependent inflammatory conditions.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Nitrilos/farmacologia , Corantes de Rosanilina/farmacologia , Animais , Caspase 1/metabolismo , Colite/induzido quimicamente , Colite Ulcerativa/metabolismo , Citocinas/metabolismo , Sulfato de Dextrana/farmacologia , Inflamassomos/efeitos dos fármacos , Inflamassomos/metabolismo , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Masculino , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Nitrilos/metabolismo , Ratos , Ratos Wistar , Receptores Purinérgicos P2X7/metabolismo , Corantes de Rosanilina/metabolismo , Transdução de Sinais/efeitos dos fármacos
4.
Ecotoxicol Environ Saf ; 212: 112012, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33550074

RESUMO

Microplastics (MPs) considered as a new persistent environmental pollutant could enter into the circulatory system and result in decrease of sperm quantity and quality in mice. However, the effects of Polystyrene MPs (PS MPs) on the ovary and its mechanism in rats remained unclear. In this present study, thirty-two healthy female Wistar rats were exposed to different concentrations of 0.5 µm PS MPs dispersed in deionized water for 90 days. Using hematoxylin-eosin (HE) staining, the number of growing follicles was decreased compared to the control group. In addition, the activity of glutathione peroxidase (GSH-Px), catalase (CAT) and superoxide dismutase (SOD) were decreased while the expression level of malondialdehyde (MDA) was increased in ovary tissue. Confirmed by immunohistochemistry, the integrated optical density of NLRP3 and Cleaved-Caspase-1 had been elevated by 13.9 and 14 in granulosa cells in the 1.5 mg/kg/d group. Furthermore, compared to the control group, the level of AMH had been decreased by 23.3 pg/ml while IL-1ß and IL-18 had been increased by 32 and 18.5 pg/ml in the 1.5 mg/kg/d group using the enzyme-linked immune sorbent assay (ELISA). Besides, the apoptosis of granulosa cells was elevated measured by terminal deoxyribonucleotide transferase-mediated nick end labeling (TUNEL) staining and flow cytometry. Moreover, western blot assays showed that the expressions of NLRP3/Caspase-1 signaling pathway related factors and Cleaved-Caspase-3 were increased. These results demonstrated that PS MPs could induce pyroptosis and apoptosis of ovarian granulosa cells via the NLRP3/Caspase-1 signaling pathway maybe triggered by oxidative stress. The present study suggested that exposure to microplastics had adverse effects on ovary and could be a potential risk factor for female infertility, which provided new insights into the toxicity of MPs on female reproduction.


Assuntos
Apoptose/efeitos dos fármacos , Caspase 1/metabolismo , Microplásticos/toxicidade , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ovário/efeitos dos fármacos , Poliestirenos/toxicidade , Piroptose/efeitos dos fármacos , Animais , Feminino , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Células da Granulosa/patologia , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Malondialdeído/metabolismo , Ovário/metabolismo , Ovário/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Transdução de Sinais
5.
Int J Mol Sci ; 22(2)2021 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33467177

RESUMO

The inflammasome is a three-component (sensor, adaptor, and effector) filamentous signaling platform that shields from multiple pathogenic infections by stimulating the proteolytical maturation of proinflammatory cytokines and pyroptotic cell death. The signaling process initiates with the detection of endogenous and/or external danger signals by specific sensors, followed by the nucleation and polymerization from sensor to downstream adaptor and then to the effector, caspase-1. Aberrant activation of inflammasomes promotes autoinflammatory diseases, cancer, neurodegeneration, and cardiometabolic disorders. Therefore, an equitable level of regulation is required to maintain the equilibrium between inflammasome activation and inhibition. Recent advancement in the structural and mechanistic understanding of inflammasome assembly potentiates the emergence of novel therapeutics against inflammasome-regulated diseases. In this review, we have comprehensively discussed the recent and updated insights into the structure of inflammasome components, their activation, interaction, mechanism of regulation, and finally, the formation of densely packed filamentous inflammasome complex that exists as micron-sized punctum in the cells and mediates the immune responses.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Proteínas Adaptadoras de Sinalização CARD/química , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Caspase 1/química , Caspase 1/metabolismo , Proteínas de Ligação a DNA/química , Humanos , Inflamassomos/química , Proteína 3 que Contém Domínio de Pirina da Família NLR/química , Domínios Proteicos , Multimerização Proteica
6.
Arch Biochem Biophys ; 699: 108753, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33453207

RESUMO

This review takes a closer look at the structural components of the molecules involved in the processes leading to caspase-1 activation. Interleukins 1ß and 18 (IL-1ß, IL-18) are well-known proinflammatory cytokines that are produced following cleavage of their respective precursor proteins by the cysteine protease caspase-1. Active caspase-1 is the final step of the NLRP3 inflammasome, a three-protein intracellular complex involved in inflammation and induction of pyroptosis (a proinflammatory cell-death process). NLRP3 activators facilitate assembly of the inflammasome complex and subsequent activation of caspase-1 by autoproteolysis. However, the definitive structural components of active caspase-1 are still unclear and new data add to the complexity of this process. This review outlines the historical and recent findings that provide supporting evidence for the structural aspects of caspase-1 autoproteolysis and activation.


Assuntos
Caspase 1/metabolismo , Animais , Caspase 1/química , Linhagem Celular Tumoral , Ativação Enzimática/fisiologia , Humanos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Multimerização Proteica/fisiologia , Proteólise
7.
J Agric Food Chem ; 69(3): 982-991, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33427450

RESUMO

Lipopolysaccharide (LPS)-induced liver injury is the main factor in acute liver failure. The current study aims to investigate the protection of limonin, an antioxidant compound from citrus fruit, against LPS-induced liver toxicity and elucidate the potential mechanisms. We found that limonin elevated cell viability and reduced LDH release in LPS-treated HepG2 cells. Limonin also inhibited LPS-induced pyroptosis by inhibiting membrane rupture, reducing ROS generation, and decreasing gasdermin D activation. Moreover, limonin inhibited the formation of a NOD-like receptor protein 3 (NLRP3)/Apoptosis-associated speck-like protein containing a CARD (ASC) complex by reducing the related protein expression and the colocalization cytosolic of NLRP3 and caspase-1 and then suppressed IL-1ß maturation. Ultimately, we established LPS-induced hepatotoxicity in vivo by using C57BL/6 mice administrated LPS (10 mg/kg) intraperitoneally and limonin (50 and 100 mg/kg) orally. We found that limonin dereased the serum ALT and AST activity and LDH release and increased the hepatic GSH amount in LPS-treated mice. Additionally, the liver histological evaluation revealed that limonin protects against LPS-induced liver damage. We further demonstrated that limonin ameliorated LPS-induced hepatotoxicity by inhibiting pyroptosis via the NLRP3/gasdermin D signaling pathway. In summary, this study uncovered the mechanism whereby limonin mitigated LPS-induced hepatotoxicity and documented that limonin might be a promising candidate drug for LPS-induced hepatotoxicity.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteínas de Ligação a Fosfato/metabolismo , Piroptose/efeitos dos fármacos , Animais , Caspase 1/genética , Caspase 1/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/fisiopatologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Limoninas , Lipopolissacarídeos/efeitos adversos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteínas de Ligação a Fosfato/genética
8.
Nat Commun ; 12(1): 189, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420033

RESUMO

NLRP1 and CARD8 are related cytosolic sensors that upon activation form supramolecular signalling complexes known as canonical inflammasomes, resulting in caspase-1 activation, cytokine maturation and/or pyroptotic cell death. NLRP1 and CARD8 use their C-terminal (CT) fragments containing a caspase recruitment domain (CARD) and the UPA (conserved in UNC5, PIDD, and ankyrins) subdomain for self-oligomerization, which in turn form the platform to recruit the inflammasome adaptor ASC (apoptosis-associated speck-like protein containing a CARD) or caspase-1, respectively. Here, we report cryo-EM structures of NLRP1-CT and CARD8-CT assemblies, in which the respective CARDs form central helical filaments that are promoted by oligomerized, but flexibly linked, UPAs surrounding the filaments. Through biochemical and cellular approaches, we demonstrate that the UPA itself reduces the threshold needed for NLRP1-CT and CARD8-CT filament formation and signalling. Structural analyses provide insights on the mode of ASC recruitment by NLRP1-CT and the contrasting direct recruitment of caspase-1 by CARD8-CT. We also discover that subunits in the central NLRP1CARD filament dimerize with additional exterior CARDs, which roughly doubles its thickness and is unique among all known CARD filaments. Finally, we engineer and determine the structure of an ASCCARD-caspase-1CARD octamer, which suggests that ASC uses opposing surfaces for NLRP1, versus caspase-1, recruitment. Together these structures capture the architecture and specificity of the active NLRP1 and CARD8 inflammasomes in addition to key heteromeric CARD-CARD interactions governing inflammasome signalling.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Anquirinas/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Inflamassomos/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/genética , Anquirinas/química , Apoptose , Proteínas Reguladoras de Apoptose/química , Proteínas Reguladoras de Apoptose/genética , Proteínas Adaptadoras de Sinalização CARD/química , Proteínas Adaptadoras de Sinalização CARD/genética , Caspase 1/metabolismo , Domínio de Ativação e Recrutamento de Caspases , Microscopia Crioeletrônica , Proteínas Adaptadoras de Sinalização de Receptores de Domínio de Morte/química , Proteínas Adaptadoras de Sinalização de Receptores de Domínio de Morte/metabolismo , Células HEK293 , Humanos , Inflamassomos/química , Inflamassomos/ultraestrutura , Modelos Moleculares , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Domínios e Motivos de Interação entre Proteínas , Transdução de Sinais
9.
J Agric Food Chem ; 69(4): 1291-1299, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33475360

RESUMO

Lycopene (Lyc) as a natural antioxidant has attracted widespread attention. Di(2-ethylhexyl) phthalate (DEHP) can cause serious spleen injury in animals via the environment and food chain. For investigation of whether Lyc could alleviate DEHP-exerted pyroptosis in spleen through inhibiting the Caspase-1/NLRP3 pathway activation, 140 male mice were randomly divided into 7 groups: control group, vehicle control group, Lyc group (5 mg/kg BW/day), DEHP-exposed group (500 or 1000 mg/kg BW/day, respectively), and DEHP + Lyc groups by daily administration for 28 days. Pathological results showed that the supplementation of Lyc alleviated DEHP-induced inflammatory infiltration. Moreover, the addition of Lyc inhibited DEHP-induced Caspase-1, NLRP3, ASC, NF-κB, IL-1ß, and IL-18 overexpression and GSDMD down-expression. These results indicate that Lyc could inhibit DEHP-induced Caspase-1-dependent pyroptosis and the inflammatory response. Taken together, the study provided new evidence that Lyc may be a strategy to mitigate spleen injury induced by DEHP.


Assuntos
Caspase 1/metabolismo , Dietilexilftalato/toxicidade , Licopeno/administração & dosagem , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose/efeitos dos fármacos , Baço/efeitos dos fármacos , Animais , Caspase 1/genética , Masculino , Camundongos , Camundongos Endogâmicos ICR , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Baço/metabolismo
10.
Life Sci ; 269: 119090, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33465393

RESUMO

AIMS: Pyroptosis and inflammation are involved in the development of chronic obstructive pulmonary disease (COPD). However, the cigarette smoke-mediated mechanism of COPD remains unclear. In this study, we aimed to investigate the role of nucleotide-binding domain-like receptor protein-3 (NLRP3) inflammasome-mediated pyroptosis in the death of human bronchial epithelial (HBE) cells after cigarette smoke extract (CSE) exposure. MAIN METHODS: The protein level of NLRP3 in lung tissue was measured after cigarette smoke exposure in vivo. In vitro, HBE cells were treated with CSE. Subsequently, the activity of caspase-1, lactate dehydrogenase (LDH) release, release of interleukin (IL)-1ß and NLRP3 expression levels were measured. The involvement of reactive oxygen species (ROS) was also explored. KEY FINDINGS: After exposure to CSE, increased release of LDH, the transcriptional and translational upregulation of NLRP3, the caspase-1 activity levels, and enhanced IL-1ß and IL-18 release were observed in 16HBE cells. In addition, NLRP3 was required to activate the caspase-1. Our results suggested that pre-stimulated of 16HBE with a caspase-1 inhibitor, or using NLRP3 siRNA to silence NLRP3 expression, also caused the decrease of IL-1ß release and pyroptosis. SIGNIFICANCES: CSE induced inflammation and contributed to pyroptosis through the ROS/NLRP3/caspase-1 pathway in 16HBE cells. The NLRP3 inflammasome participates in CSE-induced HBE cell damage and pyroptosis, which could provide new insights into COPD.


Assuntos
Brônquios/patologia , Caspase 1/metabolismo , Células Epiteliais/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Doença Pulmonar Obstrutiva Crônica/patologia , Piroptose , Espécies Reativas de Oxigênio/metabolismo , Fumaça/efeitos adversos , Animais , Brônquios/efeitos dos fármacos , Brônquios/metabolismo , Caspase 1/genética , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Inflamassomos/efeitos dos fármacos , Inflamassomos/metabolismo , Inflamação/etiologia , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Estresse Oxidativo/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/etiologia , Doença Pulmonar Obstrutiva Crônica/metabolismo , Transdução de Sinais , Tabaco
11.
Nat Commun ; 12(1): 188, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420028

RESUMO

Nod-like receptor (NLR) proteins activate pyroptotic cell death and IL-1 driven inflammation by assembling and activating the inflammasome complex. Closely related sensor proteins NLRP1 and CARD8 undergo unique auto-proteolysis-dependent activation and are implicated in auto-inflammatory diseases; however, their mechanisms of activation are not understood. Here we report the structural basis of how the activating domains (FIINDUPA-CARD) of NLRP1 and CARD8 self-oligomerize to assemble distinct inflammasome complexes. Recombinant FIINDUPA-CARD of NLRP1 forms a two-layered filament, with an inner core of oligomerized CARD surrounded by an outer ring of FIINDUPA. Biochemically, self-assembled NLRP1-CARD filaments are sufficient to drive ASC speck formation in cultured human cells-a process that is greatly enhanced by NLRP1-FIINDUPA which forms oligomers in vitro. The cryo-EM structures of NLRP1-CARD and CARD8-CARD filaments, solved here at 3.7 Å, uncover unique structural features that enable NLRP1 and CARD8 to discriminate between ASC and pro-caspase-1. In summary, our findings provide structural insight into the mechanisms of activation for human NLRP1 and CARD8 and reveal how highly specific signaling can be achieved by heterotypic CARD interactions within the inflammasome complexes.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Inflamassomos/química , Inflamassomos/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Reguladoras de Apoptose/química , Proteínas Reguladoras de Apoptose/genética , Proteínas Adaptadoras de Sinalização CARD/genética , Caspase 1/metabolismo , Microscopia Crioeletrônica , Células HEK293 , Humanos , Inflamassomos/genética , Inflamação , Simulação de Acoplamento Molecular , Mutação , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Transdução de Sinais
12.
Ecotoxicol Environ Saf ; 207: 111306, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32949934

RESUMO

Although studies have demonstrated that fine particulate matter (PM2.5) induces ocular surface damage, PM2.5 exposure causes cornea toxicity is not entirely clear. The aim of this study is to investigate the role of the nod-like receptor family pyrin domain containing three (NLRP3) inflammasome-mediated pyroptosis in PM2.5-related corneal toxicity. Human corneal epithelial cells (HCECs) were exposed to different concentrations of PM2.5, and the cell viability, expressions of NLRP3 inflammasome mediated pyroptosis axis molecules and intracellular reactive oxygen species (ROS) formation were measured in HCECs. Animal experiments were undertaken to topically apply PM2.5 suspension to mouse eyes for three months and the pyroptosis related molecules in the mouse corneas were measured. RESULTS: Our results showed a dose-dependent decrease of HCEC viability in the PM2.5-treated cells. NLRP3 inflammasome-mediated pyroptosis axis (NLRP3, ASC, GSDMD, caspase-1, IL-1ß, and IL-18) were activated in the PM2.5-treated HCECs, accompanied by increased ROS formation. Further in vivo study confirmed the activation of this pathway in the mouse corneas exposed to PM2.5. In conclusion, this study provids novel evidence that PM2.5 induces corneal toxicity by triggering cell pyroptosis.


Assuntos
Córnea/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Material Particulado/toxicidade , Piroptose/efeitos dos fármacos , Animais , Caspase 1/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Córnea/patologia , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Humanos , Inflamação , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Camundongos , Espécies Reativas de Oxigênio/metabolismo
13.
Front Immunol ; 11: 583373, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33149733

RESUMO

Coronaviruses (CoVs) are members of the genus Betacoronavirus and the Coronaviridiae family responsible for infections such as severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and more recently, coronavirus disease-2019 (COVID-19). CoV infections present mainly as respiratory infections that lead to acute respiratory distress syndrome (ARDS). However, CoVs, such as COVID-19, also present as a hyperactivation of the inflammatory response that results in increased production of inflammatory cytokines such as interleukin (IL)-1ß and its downstream molecule IL-6. The inflammasome is a multiprotein complex involved in the activation of caspase-1 that leads to the activation of IL-1ß in a variety of diseases and infections such as CoV infection and in different tissues such as lungs, brain, intestines and kidneys, all of which have been shown to be affected in COVID-19 patients. Here we review the literature regarding the mechanism of inflammasome activation by CoV infection, the role of the inflammasome in ARDS, ventilator-induced lung injury (VILI), and Disseminated Intravascular Coagulation (DIC) as well as the potential mechanism by which the inflammasome may contribute to the damaging effects of inflammation in the cardiac, renal, digestive, and nervous systems in COVID-19 patients.


Assuntos
Caspase 1/metabolismo , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/patologia , Síndrome da Liberação de Citocina/patologia , Inflamassomos/imunologia , Pneumonia Viral/imunologia , Pneumonia Viral/patologia , Betacoronavirus/imunologia , Coagulação Intravascular Disseminada/patologia , Humanos , Inflamação/patologia , Interleucina-1beta/metabolismo , Pandemias , Síndrome Respiratória Aguda Grave/patologia , Lesão Pulmonar Induzida por Ventilação Mecânica/patologia
14.
J Toxicol Sci ; 45(11): 673-680, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33132241

RESUMO

The epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) have been approved for non-small cell lung cancer. Although EGFR TKIs are less toxic than traditional cytotoxic therapies, they cause many severe idiosyncratic drug reactions. Reactive metabolites can cause cellular damage with the release of danger-associated molecular patterns (DAMPs), which is thought to be involved in immune activation. Inflammasomes can be activated by DAMPs, and this may be a common mechanism by which DAMPs initiate an immune response. We tested the ability of afatinib, dacomitinib, erlotinib, gefitinib, and osimertinib to induce the release of DAMPs that activate inflammasomes. Human hepatocarcinoma functional liver cell-4 (FLC-4) cells were used for bioactivation of drugs, and the detection of inflammasome activation was performed with the human macrophage cell line, THP-1 cells. Gefitinib is known to be oxidized to a reactive iminoquinone metabolite. We found that the supernatant from the incubation of gefitinib with FLC-4 cells for 7 days led to increased caspase-1 activity and production of IL-1ß by THP-1 cells. In the supernatant of FLC-4 cells with gefitinib, the heat shock protein (HSP) 40, 70 and 90 were significantly increased. In addition, activated THP-1 cells secreted high mobility group box 1 (HMGB1) protein. These results support the hypothesis that the reactive iminoquinone metabolite can cause the release of DAMPs from hepatocytes, which in turn, can activate inflammasomes. Inflammasome activation may be an important step in the activation of the immune system by gefitinib, which in some patients, can cause immune-related adverse events.


Assuntos
Meios de Cultura/efeitos adversos , Gefitinibe/efeitos adversos , Hepatócitos , Inflamassomos/imunologia , Ativação de Macrófagos/efeitos dos fármacos , Inibidores de Proteínas Quinases/efeitos adversos , Células THP-1/imunologia , Alarminas/metabolismo , Caspase 1/metabolismo , Linhagem Celular , Gefitinibe/metabolismo , Proteína HMGB1/metabolismo , Humanos , Interleucina-1beta/metabolismo , Inibidores de Proteínas Quinases/metabolismo , Quinonas/efeitos adversos , Quinonas/metabolismo , Células THP-1/metabolismo
15.
J Toxicol Sci ; 45(10): 651-660, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33012733

RESUMO

Inhalation of silica particles leads to pulmonary inflammatory responses. Clara cell protein 16 (CC16) has been reported to played a protective role in inflammatory lung diseases. However, its role on silica particles-induced inflammation has not been fully clarified. In this study, THP-1 macrophages were exposed to 75 µg/cm2 silica particles with or without 2 µg/mL exogenous CC16 (recombinant CC16, rCC16) for 24 hr. The production of inflammatory cytokines, including interleukin (IL)-1ß, tumor necrosis factor (TNF)-α and IL-6, in the cell supernatants of different groups was detected through ELISA kits and real-time RT-PCR, respectively. The nuclear translocation of nuclear factor (NF)-κB, protein levels of pro-IL-1ß, the nucleotide-binding domain-like receptor protein 3 (NLRP3) and caspase-1 were evaluated via immunofluorescence or western blot. Results showed that, at 75 µg/cm2 silica particle concentration, the treatment of rCC16 significantly decreased IL-1ß, TNF-α and IL-6 protein release and mRNA levels in THP-1 macrophages. Compared to those only exposed to silica particles, THP-1 macrophages exposed to both silica particles and rCC16 showed significantly lower nuclear levels and higher cytosol levels of NF-κB p65, as well as lower co-localization coefficients through immunofluorescence. Additionally, the administration of rCC16 significantly attenuated the increase of pro-IL-1ß, NLRP3 and caspase-1 levels induced by silica particle exposure. Our results suggested that exogenous CC16 could inhibit silica particles-induced inflammation in THP-1 macrophages, mainly through suppressing NF-κB pathway and caspase-1 activation.


Assuntos
Caspase 1/metabolismo , Expressão Gênica/efeitos dos fármacos , Inflamação/genética , Macrófagos Alveolares/imunologia , Macrófagos/imunologia , NF-kappa B/metabolismo , Dióxido de Silício/toxicidade , Caspase 1/genética , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Humanos , NF-kappa B/genética , Tamanho da Partícula , Proteínas Recombinantes/farmacologia , Células THP-1 , Uteroglobina/farmacologia
16.
Mol Immunol ; 127: 136-145, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32971400

RESUMO

Sepsis-induced inflammatory damage is a crucial cause of acute kidney injury (AKI), and AKI is an ecumenical fearful complication in approximately half of patients with sepsis. CCAAT/enhancer-binding protein ß (C/EBPß) plays roles in regulating acute phase responses and inflammation. However, the role and mechanism of C/EBPß in AKI are unclear. LPS combined with ATP-treated renal epithelial cells HK2 and cecal ligation-peferation (CLP)-mice were used as models of AKI in vitro and in vivo. Cell damage, the secretion of interleukin-1 beta (IL-1ß), IL-18 and cysteinyl aspartate specific proteinase 1 (caspase-1) activity were tested by LDH, ELISA assay and flow cytometry analysis, respectively. The expression levels of TFAM, C/EBPß, and pyroptosis-related molecules were tested by qRT-PCR and Western blotting. Chromatin immunoprecipitation (ChIP) assessed the interaction between C/EBPß with TFAM. Hematoxylin-Eosin (H&E) staining detected pathological changes of kidney tissues, and immunohistochemistry measured TFAM and C/EBPß in mice kidney tissues. C/EBPß or TFAM were up-regulated in LPS combined with ATP -induced HK2 cells. Knockdown of C/EBPß could suppress cell injury and the secretion of IL-1ß and IL-18 induced by LPS combined with ATP. Furthermore, C/EBPß up-regulated the expression levels of TFAM via directly binding to TFAM promoter. Overexpression of TFAM reversed the effects of C/EBPß deficiency on pyroptosis. Knockdown of C/EBPß could inhibit NLRP3 inflammasome-mediated caspase-1 signaling pathway by inactivating TFAM/RAGE pathway. It was further confirmed in the AKI mice that C/EBPß and TFAM promoted AKI by activating NLRP3-mediated pyroptosis. The interaction of between C/EBPß and TFAM facilitated pyroptosis by activating NLRP3/caspase-1 signal axis, thereby promoting the occurrence of AKI.


Assuntos
Lesão Renal Aguda/metabolismo , Lesão Renal Aguda/patologia , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Grupo de Alta Mobilidade/metabolismo , Inflamassomos/metabolismo , Proteínas Mitocondriais/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose , Fatores de Transcrição/metabolismo , Trifosfato de Adenosina , Animais , Caspase 1/metabolismo , Linhagem Celular , Humanos , Inflamação/patologia , Lipopolissacarídeos , Masculino , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas/genética , Ligação Proteica , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Transdução de Sinais
17.
Nat Commun ; 11(1): 4596, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32929083

RESUMO

Earlier studies indicate that either the canonical or non-canonical pathways of inflammasome activation have a limited role on malaria pathogenesis. Here, we report that caspase-8 is a central mediator of systemic inflammation, septic shock in the Plasmodium chabaudi-infected mice and the P. berghei-induced experimental cerebral malaria (ECM). Importantly, our results indicate that the combined deficiencies of caspases-8/1/11 or caspase-8/gasdermin-D (GSDM-D) renders mice impaired to produce both TNFα and IL-1ß and highly resistant to lethality in these models, disclosing a complementary, but independent role of caspase-8 and caspases-1/11/GSDM-D in the pathogenesis of malaria. Further, we find that monocytes from malaria patients express active caspases-1, -4 and -8 suggesting that these inflammatory caspases may also play a role in the pathogenesis of human disease.


Assuntos
Caspase 8/metabolismo , Inflamação/patologia , Malária Cerebral/enzimologia , Animais , Encéfalo/patologia , Caspase 1/metabolismo , Células Dendríticas/metabolismo , Ativação Enzimática , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica , Humanos , Interferon gama/metabolismo , Interleucina-1beta/metabolismo , Lipopolissacarídeos , Malária Cerebral/genética , Camundongos Endogâmicos C57BL , Monócitos/metabolismo , Plasmodium chabaudi/fisiologia , Baço/metabolismo , Receptores Toll-Like/metabolismo
18.
Nat Commun ; 11(1): 4766, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32958778

RESUMO

Germline telomere maintenance defects are associated with an increased incidence of inflammatory diseases in humans, yet whether and how telomere dysfunction causes inflammation are not known. Here, we show that telomere dysfunction drives pATM/c-ABL-mediated activation of the YAP1 transcription factor, up-regulating the major pro-inflammatory factor, pro-IL-18. The colonic microbiome stimulates cytosolic receptors activating caspase-1 which cleaves pro-IL-18 into mature IL-18, leading to recruitment of interferon (IFN)-γ-secreting T cells and intestinal inflammation. Correspondingly, patients with germline telomere maintenance defects exhibit DNA damage (γH2AX) signaling together with elevated YAP1 and IL-18 expression. In mice with telomere dysfunction, telomerase reactivation in the intestinal epithelium or pharmacological inhibition of ATM, YAP1, or caspase-1 as well as antibiotic treatment, dramatically reduces IL-18 and intestinal inflammation. Thus, telomere dysfunction-induced activation of the ATM-YAP1-pro-IL-18 pathway in epithelium is a key instigator of tissue inflammation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ciclo Celular/metabolismo , Inflamação/patologia , Telômero/patologia , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Antibacterianos/uso terapêutico , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Caspase 1/metabolismo , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/genética , Criança , Colo/metabolismo , Colo/microbiologia , Colo/patologia , Gastroenteropatias/patologia , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/fisiologia , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/microbiologia , Interleucina-18/genética , Interleucina-18/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Camundongos , Camundongos Mutantes , Fosforilação , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Transdução de Sinais , Telomerase/genética , Telomerase/metabolismo
19.
Mol Cell ; 80(1): 43-58.e7, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32937100

RESUMO

Immune cell function depends on specific metabolic programs dictated by mitochondria, including nutrient oxidation, macromolecule synthesis, and post-translational modifications. Mitochondrial adaptations have been linked to acute and chronic inflammation, but the metabolic cues and precise mechanisms remain unclear. Here we reveal that histone deacetylase 3 (HDAC3) is essential for shaping mitochondrial adaptations for IL-1ß production in macrophages through non-histone deacetylation. In vivo, HDAC3 promoted lipopolysaccharide-induced acute inflammation and high-fat diet-induced chronic inflammation by enhancing NLRP3-dependent caspase-1 activation. HDAC3 configured the lipid profile in stimulated macrophages and restricted fatty acid oxidation (FAO) supported by exogenous fatty acids for mitochondria to acquire their adaptations and depolarization. Rather than affecting nuclear gene expression, HDAC3 translocated to mitochondria to deacetylate and inactivate an FAO enzyme, mitochondrial trifunctional enzyme subunit α. HDAC3 may serve as a controlling node that balances between acquiring mitochondrial adaptations and sustaining their fitness for IL-1ß-dependent inflammation.


Assuntos
Ácidos Graxos/metabolismo , Histona Desacetilases/metabolismo , Inflamação/metabolismo , Interleucina-1beta/metabolismo , Mitocôndrias/metabolismo , Adulto , Animais , Caspase 1/metabolismo , Feminino , Humanos , Inflamação/patologia , Metabolismo dos Lipídeos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Mitocôndrias/ultraestrutura , Subunidade alfa da Proteína Mitocondrial Trifuncional/metabolismo , Células Mieloides/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Oxirredução , Fosforilação Oxidativa , Adulto Jovem
20.
Nat Protoc ; 15(10): 3284-3333, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32895525

RESUMO

Inflammasomes are multimeric heterogeneous mega-Dalton protein complexes that play key roles in the host innate immune response to infection and sterile insults. Assembly of the inflammasome complex following infection or injury begins with the oligomerization of the upstream inflammasome-forming sensor and proceeds through a multistep process of well-coordinated events and downstream effector functions. Together, these steps enable elegant experimental readouts with which to reliably assess the successful activation of the inflammasome complex and cell death. Here, we describe a comprehensive protocol that details several in vitro (in bone marrow-derived macrophages) and in vivo (in mice) strategies for activating the inflammasome and explain how to subsequently assess multiple downstream effects in parallel to unequivocally establish the activation status of the inflammasome and cell death pathways. Our workflow assesses inflammasome activation via the formation of the apoptosis-associated speck-like protein containing a CARD (ASC) speck; cleavage of caspase-1 and gasdermin D; release of IL-1ß, IL-18, caspase-1, and lactate dehydrogenase from the cell; and real-time analysis of cell death by imaging. Analyses take up to ~24 h to complete. Overall, our multifaceted approach provides a comprehensive and consistent protocol for assessing inflammasome activation and cell death.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Inflamassomos/metabolismo , Inflamassomos/fisiologia , Animais , Apoptose , Caspase 1/metabolismo , Morte Celular/fisiologia , Feminino , Imunidade Inata , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , L-Lactato Desidrogenase/metabolismo , Macrófagos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Neoplasias/metabolismo
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