RESUMO
Cigarette smoke (CS) is a major risk factor for chronic lung diseases and promotes activation of pattern recognition receptors in the bronchial epithelium. NOD-like receptor family, pyrin domain-containing 3 (NLRP3) is a pattern recognition receptor whose activation leads to caspase-1 cleavage, maturation/release of IL-1ß and IL-18, and eventually pyroptosis. Whether the NLRP3 inflammasome participates in CS-induced inflammation in bronchial epithelial cells is still unclear. Herein, we evaluated the involvement of NLRP3 in CS-induced inflammatory responses in human primary bronchial epithelial cells. To this purpose, human primary bronchial epithelial cells were stimulated with CS extracts (CSE) and lytic cell death, caspase activation (-1, -8, -3/7), cytokine release (IL-1ß, IL-18, and IL-8), NLRP3, pro-IL-1ß/pro-IL-18 mRNA, and protein expression were measured. The impact of inhibitors of NLRP3 (MCC950), caspases, and the effect of the antioxidant N-acetyl cysteine were evaluated. We found that CSE increased pro-IL-1ß expression and induced activation of caspase-1 and release of IL-1ß and IL-18. These events were independent of NLRP3 and we found that NLRP3 was not expressed. N-acetyl cysteine reverted CSE-induced caspase-1 activation. Overall, our findings support that the bronchial epithelium may play a central role in the release of IL-1 family cytokines independently of NLRP3 in the lungs of smokers.
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Mechanisms and consequences of gasdermin D (GSDMD) activation in cigarette smoke (CS)-associated inflammation and lung disease are unknown. GSDMD is a downstream effector of caspase-1, -8, and -4. Upon cleavage, GSDMD generates pores into cell membranes. Different degrees of GSDMD activation are associated with a range of physiological outputs ranging from cell hyperactivation to pyroptosis. We have previously reported that in human monocyte-derived macrophages CS extract (CSE) inhibits the NLRP3 inflammasome and shifts the response to lipopolysaccharide (LPS) towards the TLR4-TRIF axis leading to activation of caspase-8, which, in turn, activates caspase-1. In the present work, we investigated whether other ASC-dependent inflammasomes could be involved in caspase activation by CSE and whether caspase activation led to GSDMD cleavage and other downstream effects. Presented results demonstrate that CSE promoted ASC-independent activation of caspase-1 leading to GSDMD cleavage and increased cell permeability, in the absence of cell death. GSDMD cleavage was strongly enhanced upon stimulation with LPS+CSE, suggesting a synergistic effect between the two stimuli. Noteworthy, CSE promoted LPS internalization leading to caspase-4 activation, thus contributing to increased GSDMD cleavage. Caspase-dependent GSDMD cleavage was associated with mitochondrial superoxide generation. Increased cleaved GSDMD was found in lung macrophages of smokers compared to ex-smokers and non-smoking controls. Our findings revealed that ASC-independent activation of caspase-1, -4, and -8 and GSDMD cleavage upon exposure to CS may contribute to macrophage dysfunction and feed the chronic inflammation observed in the smokers' lung.
Assuntos
Caspases Iniciadoras/metabolismo , Fumar Cigarros , Inflamassomos , Proteínas de Ligação a Fosfato/metabolismo , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Caspase 1/metabolismo , Caspases/metabolismo , Humanos , Inflamassomos/metabolismo , Inflamação/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/toxicidade , Macrófagos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Nicotiana/metabolismoRESUMO
Exposure of the airways epithelium to environmental insults, including cigarette smoke, results in increased oxidative stress due to unbalance between oxidants and antioxidants in favor of oxidants. Oxidative stress is a feature of inflammation and promotes the progression of chronic lung diseases, including Chronic Obstructive Pulmonary Disease (COPD). Increased oxidative stress leads to exhaustion of antioxidant defenses, alterations in autophagy/mitophagy and cell survival regulatory mechanisms, thus promoting cell senescence. All these events are amplified by the increase of inflammation driven by oxidative stress. Several models of bronchial epithelial cells are used to study the molecular mechanisms and the cellular functions altered by cigarette smoke extract (CSE) exposure, and to test the efficacy of molecules with antioxidant properties. This review offers a comprehensive synthesis of human in-vitro and ex-vivo studies published from 2011 to 2021 describing the molecular and cellular mechanisms evoked by CSE exposure in bronchial epithelial cells, the most used experimental models and the mechanisms of action of cellular antioxidants systems as well as natural and synthetic antioxidant compounds.
Assuntos
Fumar Cigarros/efeitos adversos , Células Epiteliais/efeitos dos fármacos , Estresse Oxidativo , Animais , Brônquios/efeitos dos fármacos , Brônquios/metabolismo , Brônquios/fisiopatologia , Células Epiteliais/metabolismo , Células Epiteliais/fisiologia , Humanos , InflamaçãoRESUMO
The NLRP3 inflammasome is formed by the sensor NLRP3, the adaptor ASC, and pro-caspase-1. Assembly and activation of the inflammasome trigger caspase-1-dependent cleavage of pro-IL-1ß and pro-IL-18 into their secreted forms. Cigarette smoke is a risk factor for chronic inflammatory diseases and is associated with macrophage dysfunction. The impact of cigarette smoke on NLRP3-dependent responses in macrophages is largely unknown. Herein, we investigated the effects of cigarette smoke extract (CSE) on the NLRP3 inflammasome in human monocyte-derived macrophages (MDMs) and THP-1 cells stimulated with lipopolysaccharide (LPS) and LPS plus the NLRP3 inflammasome activator ATP. We found that CSE inhibited the release of IL-1ß and IL-18 as well as the expression of NLRP3 acting mainly at the transcriptional level. Interestingly, we found that CSE increased the caspase-1 activity via an NLRP3-independent and TLR4-TRIF-caspase-8-dependent pathway. Activation of caspase-1 by CSE led to a reduction of the basal glycolytic flux and impaired glycolytic burst in response to LPS. Overall, our findings unveil novel pathways leading to immune-metabolic alterations in human macrophages exposed to cigarette smoke. These mechanisms may contribute to macrophage dysfunction and increased risk of infection in smokers.
Assuntos
Caspase 1/metabolismo , Inflamassomos/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fumaça/efeitos adversos , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Caspase 8/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos/farmacologia , Fumar/efeitos adversos , Células THP-1 , Nicotiana/efeitos adversos , Receptor 4 Toll-Like/metabolismoRESUMO
The NLRP3 inflammasome is a multi-protein complex that initiates innate immunity responses when exposed to a wide range of stimuli, including pathogen-associated molecular patterns (PAMPs) and danger-associated molecular patterns (DAMPs). Inflammasome activation leads to the release of the pro-inflammatory cytokines interleukin (IL)-1ß and IL-18 and to pyroptotic cell death. Over-activation of NLRP3 inflammasome has been associated with several chronic inflammatory diseases. A deep knowledge of NLRP3 inflammasome biology is required to better exploit its potential as therapeutic target and for the development of new selective drugs. To this purpose, in the past few years, several tools have been developed for the biological characterization of the multimeric inflammasome complex, the identification of the upstream signaling cascade leading to inflammasome activation, and the downstream effects triggered by NLRP3 activation. In this review, we will report cellular models and cellular, biochemical, and biophysical assays that are currently available for studying inflammasome biology. A special focus will be on those models/assays that have been used to identify NLRP3 inhibitors and their mechanism of action.
Assuntos
Inflamassomos/metabolismo , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Alarminas/metabolismo , Animais , Humanos , Imunidade Inata , Modelos Biológicos , Moléculas com Motivos Associados a Patógenos/metabolismo , Piroptose , Transdução de SinaisRESUMO
NLRP3 (NOD-like receptor family, pyrin domain-containing protein 3) activation has been linked to several chronic pathologies, including atherosclerosis, type-II diabetes, fibrosis, rheumatoid arthritis, and Alzheimer's disease. Therefore, NLRP3 represents an appealing target for the development of innovative therapeutic approaches. A few companies are currently working on the discovery of selective modulators of NLRP3 inflammasome. Unfortunately, limited structural data are available for this target. To date, MCC950 represents one of the most promising noncovalent NLRP3 inhibitors. Recently, a possible region for the binding of MCC950 to the NLRP3 protein was described but no details were disclosed regarding the key interactions. In this communication, we present an in silico multiple approach as an insight useful for the design of novel NLRP3 inhibitors. In detail, combining different computational techniques, we propose consensus-retrieved protein residues that seem to be essential for the binding process and for the stabilization of the protein-ligand complex.
Assuntos
Inflamassomos/metabolismo , Mutação , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Sítios de Ligação , Humanos , Ligação de Hidrogênio , Inflamassomos/antagonistas & inibidores , Ligantes , Conformação Molecular , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/química , Ligação Proteica , Relação Estrutura-AtividadeRESUMO
Inflammation and ageing are intertwined in chronic obstructive pulmonary disease (COPD). The histone deacetylase SIRT1 and the related activation of FoxO3 protect from ageing and regulate inflammation. The role of SIRT1/FoxO3 in COPD is largely unknown. This study evaluated whether cigarette smoke, by modulating the SIRT1/FoxO3 axis, affects airway epithelial pro-inflammatory responses. Human bronchial epithelial cells (16HBE) and primary bronchial epithelial cells (PBECs) from COPD patients and controls were treated with/without cigarette smoke extract (CSE), Sirtinol or FoxO3 siRNA. SIRT1, FoxO3 and NF-κB nuclear accumulation, SIRT1 deacetylase activity, IL-8 and CCL20 expression/release and the release of 12 cytokines, neutrophil and lymphocyte chemotaxis were assessed. In PBECs, the constitutive FoxO3 expression was lower in patients with COPD than in controls. Furthermore, CSE reduced FoxO3 expression only in PBECs from controls. In 16HBE, CSE decreased SIRT1 activity and nuclear expression, enhanced NF-κB binding to the IL-8 gene promoter thus increasing IL-8 expression, decreased CCL20 expression, increased the neutrophil chemotaxis and decreased lymphocyte chemotaxis. Similarly, SIRT1 inhibition reduced FoxO3 expression and increased nuclear NF-κB. FoxO3 siRNA treatment increased IL-8 and decreased CCL20 expression in 16HBE. In conclusion, CSE impairs the function of SIRT1/FoxO3 axis in bronchial epithelium, dysregulating NF-κB activity and inducing pro-inflammatory responses.
Assuntos
Proteína Forkhead Box O3/genética , Inflamação/genética , Doença Pulmonar Obstrutiva Crônica/metabolismo , Sirtuína 1/genética , Brônquios/efeitos dos fármacos , Brônquios/metabolismo , Brônquios/patologia , Quimiocina CCL20/genética , Fumar Cigarros/efeitos adversos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Imunidade Celular/efeitos dos fármacos , Inflamação/induzido quimicamente , Inflamação/patologia , Interleucina-8/genética , NF-kappa B/genética , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/patologia , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Nicotiana/efeitos adversos , Nicotiana/químicaRESUMO
BACKGROUND: 17-Oxo-DHA is an endogenous electrophilic derivative of the omega-3 fatty acid docosahexaenoic acid (DHA) which is generated in activated macrophages by the action of cyclooxygenase-2. METHODS: The ability of 17-oxo-DHA to control inflammation and oxidative stress was tested in human macrophages (THP-1) and bronchial epithelial cell line (16HBE) stimulated with cigarette smoke extract (CSE) and lipopolysaccharide (LPS). All data were further confirmed using primary bronchial epithelial cells, alveolar macrophages and peripheral blood mononuclear cells. RESULTS: 17-Oxo-DHA was a strong inducer of the anti-oxidant response promoting Nrf2 nuclear accumulation, leading to the expression of heme oxygenase 1 and more than doubling glutathione levels. This resulted in suppression of CSE-induced ROS generation in macrophages. In macrophages, 17-oxo-DHA potently suppressed TNFα release in response to LPS, CSE and IL-1ß acting at transcriptional level via a mechanism independent of Nrf2. Externally supplemented 17-oxo-DHA displayed the same effects in the presence of the Cox-inhibitor indomethacin. The non-electrophilic 17-oxo-DHA precursor DHA did not show any biological actions, indicating that the electrophilic moiety was required for this compound to become bioactive. CONCLUSIONS: 17-Oxo-DHA promotes cytoprotective actions both in immune and structural cells. In immune cells, 17-oxo-DHA is effective in contrasting CSE- and LPS-induced oxidative damage and inflammation acting via multiple independent pathways. GENERAL SIGNIFICANCE: Herein we provide insights on how the novel endogenous electrophilic DHA-derivative 17-oxo-DHA promotes anti-oxidant and anti-inflammatory actions. Data herein reported indicate that 17-oxo-DHA is an attractive lead compound for the development of new treatments for cigarette smoke-related airway inflammatory disorders.
Assuntos
Anti-Inflamatórios/farmacologia , Ciclo-Oxigenase 2/metabolismo , Ácidos Docosa-Hexaenoicos/farmacologia , Inflamação/tratamento farmacológico , Antioxidantes/farmacologia , Linhagem Celular , Ciclo-Oxigenase 2/genética , Ácidos Docosa-Hexaenoicos/análogos & derivados , Células Epiteliais/efeitos dos fármacos , Humanos , Inflamação/induzido quimicamente , Leucócitos Mononucleares/efeitos dos fármacos , Lipopolissacarídeos/toxicidade , Macrófagos/efeitos dos fármacos , Fumar/efeitos adversosRESUMO
In this study, we investigated the beneficial effects of grapefruit IntegroPectin, derived from industrial waste grapefruit peels via hydrodynamic cavitation, on microglia cells exposed to oxidative stress conditions. Grapefruit IntegroPectin fully counteracted cell death and the apoptotic process induced by cell exposure to tert-butyl hydroperoxide (TBH), a powerful hydroperoxide. The protective effects of the grapefruit IntegroPectin were accompanied with a decrease in the amount of ROS, and were strictly dependent on the activation of the phosphoinositide 3-kinase (PI3K)/Akt cascade. Finally, IntegroPectin treatment inhibited the neuroinflammatory response and the basal microglia activation by down-regulating the PI3K- nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB)- inducible nitric oxide synthase (iNOS) cascade. These data strongly support further investigations aimed at exploring IntegroPectin's therapeutic role in in vivo models of neurodegenerative disorders, characterized by a combination of chronic neurodegeneration, oxidative stress and neuroinflammation.
Assuntos
Citrus paradisi , Microglia , Humanos , Microglia/metabolismo , Citrus paradisi/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/metabolismo , Linhagem CelularRESUMO
Hydrogen peroxide (H2O2) is a biomarker relevant for oxidative stress monitoring. Most chronic airway diseases are characterized by increased oxidative stress. To date, the main methods for the detection of this analyte are expensive and time-consuming laboratory techniques such as fluorometric and colorimetric assays. There is a growing interest in the development of electrochemical sensors for H2O2 detection due to their low cost, ease of use, sensitivity and rapid response. In this work, an electrochemical sensor based on gold nanowire arrays has been developed. Thanks to the catalytic activity of gold against hydrogen peroxide reduction and the high surface area of nanowires, this sensor allows the quantification of this analyte in a fast, efficient and selective way. The sensor was obtained by template electrodeposition and consists of gold nanowires about 5 µm high and with an average diameter of about 200 nm. The high active surface area of this electrode, about 7 times larger than a planar gold electrode, ensured a high sensitivity of the sensor (0.98 µA µM-1cm-2). The sensor allows the quantification of hydrogen peroxide in the range from 10 µM to 10 mM with a limit of detection of 3.2 µM. The sensor has excellent properties in terms of reproducibility, repeatability and selectivity. The sensor was validated by quantifying the hydrogen peroxide released by human airways A549 cells exposed or not to the pro-oxidant compound rotenone. The obtained results were validated by comparing them with those obtained by flow cytometry after staining the cells with the fluorescent superoxide-sensitive Mitosox Red probe giving a very good concordance.
Assuntos
Peróxido de Hidrogênio , Nanofios , Humanos , Peróxido de Hidrogênio/química , Nanofios/química , Ouro/química , Reprodutibilidade dos Testes , Técnicas Eletroquímicas/métodos , Células Epiteliais , EletrodosRESUMO
Multiple sclerosis (MS) is a complex autoimmune disease with multiple players. In particular, peripheral (myelin-reactive CD4+ T lymphocytes) and central immune cells (microglia) are involved in the neuroinflammatory process and are found in MS brain lesions. New nanotechnological approaches that can cross the blood-brain barrier and specifically target the key players in the disease using biocompatible nanomaterials with low immunoreactivity represent an important challenge. To this end, nanoparticles and nanovesicles have been studied to induce immune tolerance to a wide range of myelin-derived antigens as potential approaches against MS. To this aim, we extracted myelin from bovine brain and produced myelin-based nanovesicles (MyVes) by nanoprecipitation. MyVes have a diameter of about 100 nm, negative zeta potential and contain the typical proteins of the myelin sheath. The results showed that MyVes are not cytotoxic, are hemocompatibile and do not induce an inflammatory response. In vitro experiments showed that MyVes are specifically taken up by microglial cells and are able to induce the expression of the anti-inflammatory cytokine IL-4. In addition, we have used biodistribution experiments to show that MyVes are able to reach the brain after intranasal administration. Finally, MyVes induced the production of the anti-inflammatory cytokines IL-10 and IL-4 in peripheral blood mononuclear cells isolated from MS patients. Taken together, these data provide proof of concept that MyVes may represent a safe nanosystem capable of promoting anti-inflammatory effects by modulating both central and peripheral immune cells to treat neuroinflammation in MS. STATEMENT OF SIGNIFICANCE: Recently, nanoparticles and nanovesicles have been investigated as potential approaches for the treatment of neurodegenerative diseases. We propose the use of myelin nanovesicles (MyVes) as a potential application to counteract neuroinflammation in multiple sclerosis (MS). Approximately 2.8 million people worldwide are estimated to live with MS. It is an autoimmune disease directed toward various myelin-derived antigens. Both peripheral immune cells (lymphocytes) and central immune cells (microglia) actively contribute to MS brain lesions. MyVes, due to their myelin nature, specific characteristics (size, zeta potential, and presence of myelin proteins), biocompatibility, and ability to cross the blood-brain barrier, could represent the first nanosystem capable of promoting anti-inflammatory actions by modulating both central and peripheral immune cells to treat neuroinflammation in MS.
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Airway epithelium represents a physical barrier against toxic substances and pathogens but also presents pattern recognition receptors on the epithelial cells that detect pathogens leading to molecule release and sending signals that activate both the innate and adaptive immune responses. Thus, impaired airway epithelial function and poor integrity may increase the recurrence of infections. Probiotic use in respiratory diseases as adjuvant of traditional therapy is increasingly widespread. There is growing interest in the use of non-viable heat-killed bacteria, such as tyndallized bacteria (TB), due to safety concerns and to their immunomodulatory properties. This study explores in vitro the effects of a TB blend on the immune activation of airway epithelium. 16HBE bronchial epithelial cells were exposed to different concentrations of TB. Cell viability, TB internalization, TLR2 expression, IL-6, IL-8 and TGF-ßl expression/release, E-cadherin expression and wound healing were assessed. We found that TB were tolerated, internalized, increased TLR2, E-cadherin expression, IL-6 release and wound healing but decreased both IL-8 and TGF-ßl release. In conclusion, TB activate TLR2 pathway without inducing a relevant pro-inflammatory response and improve barrier function, leading to the concept that TB preserve epithelial homeostasis and could be used as strategy to prevent and to manage respiratory infection, exacerbations included.
Assuntos
Brônquios , Células Epiteliais , Imunidade Inata , Receptor 2 Toll-Like , Humanos , Receptor 2 Toll-Like/metabolismo , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Brônquios/citologia , Brônquios/imunologia , Interleucina-6/metabolismo , Probióticos , Mucosa Respiratória/imunologia , Caderinas/metabolismo , Expressão Gênica , Células Cultivadas , Interleucina-8/metabolismo , Infecções Respiratórias/imunologia , Infecções Respiratórias/microbiologia , Sobrevivência CelularRESUMO
BACKGROUND: Chronic bronchitis (CB) is a risk factor in chronic obstructive pulmonary disease (COPD) for accelerated lung function decline and increased mortality. The lung and systemic inflammatory and immunological profile of COPD patients with CB which acutely experience respiratory failure upon a disease exacerbation is unknown. METHODS: In this study, we explored the expression of Foxp3 by western blot analysis, TLR4 by immunocytochemistry and the concentrations of IP-10 and IL-8 by ELISA in the mini-bronchoalveolar lavages (mini-BAL) and in the peripheral blood of patients with respiratory failure requiring intubation and mechanical ventilation. The recruited subjects were separated into three different groups: smokers with CB and COPD (COPD, n = 18), smokers with CB but without COPD (S, n = 8) and patients without CB and without COPD (C, n = 10). RESULTS: In mini-BAL of COPD group, Foxp3 and IP-10 were significantly reduced while TLR4 was significantly increased in comparison to C. TLR4 was also increased in mini-BAL of S. In COPD peripheral blood, Foxp3 was reduced in comparison to C but no significant differences were observed for TLR4 and for IP-10. No significant differences were observed for IL-8 concentrations in the mini-BAL and in the blood of the recruited patients. The mini-BAL TLR4 expression correlated with the Clinical Infective Pulmonary Score. CONCLUSIONS: In exacerbated COPD patients with respiratory failure, lung and systemic reduced immune regulatory events (low Foxp3 expression) and lung increased innate immunity responses (high TLR4 expression) occur. These events may contribute to the increased inflammatory events leading to respiratory failure.
Assuntos
Bronquite Crônica/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Doença Pulmonar Obstrutiva Crônica/complicações , Receptor 4 Toll-Like/metabolismo , Idoso , Idoso de 80 Anos ou mais , Bronquite Crônica/sangue , Bronquite Crônica/complicações , Líquido da Lavagem Broncoalveolar , Quimiocina CXCL10/metabolismo , Feminino , Fatores de Transcrição Forkhead/sangue , Humanos , Interleucina-8/metabolismo , Contagem de Leucócitos , Masculino , Neutrófilos , Doença Pulmonar Obstrutiva Crônica/metabolismo , Respiração Artificial , Fumar , Estatísticas não Paramétricas , Receptor 4 Toll-Like/sangue , Regulação para CimaRESUMO
Macrophage polarization is a dynamic process through which macrophages acquire specific features whose extremes are represented by M1 and M2 polarization. Interleukin (IL)-6, IL-1ß, IL-12 and IL-8 belong to M1 macrophages while transforming growth factor-beta (TGF-ß belongs to M2 cytokines. M2 polarization prevalence is observed in allergic diseases. Tyndallization is a thermal process able to inactivate microorganisms and to allow their use for chronic respiratory disease treatment via immune response modulation. The present study explores the effects of a blend of tyndallized bacteria (TB) on macrophage polarization. THP-1-derived macrophages were exposed to different concentrations of TB (106, 5 × 106, 107, 5 × 107, 108 CFU/mL) and then cell viability and TB phagocytosis, and IL-8, IL-1ß, IL-6, IL-12 and TGF-ß1 gene expression and release were assessed. TB were tolerated, phagocyted and able to increase IL-8, IL-1ß and IL-6 gene expression and release IL-12 gene expression, as well as decrease TGF-ß1 gene expression and release. The effects on IL-8, IL-6 and TGF-ß1 release were confirmed in human monocyte-derived macrophages (hMDMs) exposed to TB. In conclusion, TB promote M1 polarization, and this mechanism might have valuable potential in controlling allergic diseases and infections, possibly preventing disease exacerbations.
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BACKGROUND: Lysine demethylase enzymes (KDMs) are an emerging class of therapeutic targets, that catalyse the removal of methyl marks from histone lysine residues regulating chromatin structure and gene expression. KDM4A isoform plays an important role in the epigenetic dysregulation in various cancers and is linked to aggressive disease and poor clinical outcomes. Despite several efforts, the KDM4 family lacks successful specific molecular inhibitors. RESULTS: Herein, starting from a structure-based fragments virtual screening campaign we developed a synergic framework as a guide to rationally design efficient KDM4A inhibitors. Commercial libraries were used to create a fragments collection and perform a virtual screening campaign combining docking and pharmacophore approaches. The most promising compounds were tested in-vitro by a Homogeneous Time-Resolved Fluorescence-based assay developed for identifying selective substrate-competitive inhibitors by means of inhibition of H3K9me3 peptide demethylation. 2-(methylcarbamoyl)isonicotinic acid was identified as a preliminary active fragment, displaying inhibition of KDM4A enzymatic activity. Its chemical exploration was deeply investigated by computational and experimental approaches which allowed a rational fragment growing process. The in-silico studies guided the development of derivatives designed as expansion of the primary fragment hit and provided further knowledge on the structure-activity relationship. CONCLUSIONS: Our study describes useful insights into key ligand-KDM4A protein interaction and provides structural features for the development of successful selective KDM4A inhibitors.
Assuntos
Histona Desmetilases com o Domínio Jumonji , Lisina , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Lisina/metabolismo , Metilação de DNA , Histonas/metabolismo , Relação Estrutura-AtividadeRESUMO
Cigarette smoking impairs the lung innate immune response making smokers more susceptible to infections and severe symptoms. Dysregulation of cell death is emerging as a key player in chronic inflammatory conditions. We have recently reported that short exposure of human monocyte-derived macrophages (hMDMs) to cigarette smoke extract (CSE) altered the TLR4-dependent response to lipopolysaccharide (LPS). CSE caused inhibition of the MyD88-dependent inflammatory response and activation of TRIF/caspase-8/caspase-1 pathway leading to Gasdermin D (GSDMD) cleavage and increased cell permeability. Herein, we tested the hypothesis that activation of caspase-8 by CSE increased pro-inflammatory cell death of LPS-stimulated macrophages. To this purpose, we measured apoptotic and pyroptotic markers as well as the expression/release of pro-inflammatory mediators in hMDMs exposed to LPS and CSE, alone or in combination, for 6 and 24 h. We show that LPS/CSE-treated hMDMs, but not cells treated with CSE or LPS alone, underwent lytic cell death (LDH release) and displayed apoptotic features (activation of caspase-8 and -3/7, nuclear condensation, and mitochondrial membrane depolarization). Moreover, the negative regulator of caspase-8, coded by CFLAR gene, was downregulated by CSE. Activation of caspase-3 led to Gasdermin E (GSDME) cleavage. Notably, lytic cell death caused the release of the damage-associated molecular patterns (DAMPs) heat shock protein-60 (HSP60) and S100A8/A9. This was accompanied by an impaired inflammatory response resulting in inhibited and delayed release of IL6 and TNF. Of note, increased cleaved caspase-3, higher levels of GSDME and altered expression of cell death-associated genes were found in alveolar macrophages of smoker subjects compared to non-smoking controls. Overall, our findings show that CSE sensitizes human macrophages to cell death by promoting pyroptotic and apoptotic pathways upon encountering LPS. We propose that while the delayed inflammatory response may result in ineffective defenses against infections, the observed cell death associated with DAMP release may contribute to establish chronic inflammation. CS exposure sensitizes human macrophages to pro-inflammatory cell death. Upon exposure to LPS, CS inhibits the TLR4/MyD88 inflammatory response, downregulating the pro-inflammatory genes TNF and IL6 and the anti-apoptotic gene CFLAR, known to counteract caspase-8 activity. CS enhances caspase-8 activation through TLR4/TRIF, with a partial involvement of RIPK1, resulting on the activation of caspase-1/GSDMD axis leading to increased cell permeability and DAMP release through gasdermin pores [19]. At later timepoints caspase-3 becomes strongly activated by caspase-8 triggering apoptotic events which are associated with mitochondrial membrane depolarization, gasdermin E cleavage and secondary necrosis with consequent massive DAMP release.
Assuntos
Fumar Cigarros , Doença Pulmonar Obstrutiva Crônica , Humanos , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Caspase 3/metabolismo , Caspase 8/metabolismo , Morte Celular , Gasderminas , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Macrófagos/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Nicotiana/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismoRESUMO
Electrophilic fatty acids are generated during inflammation by non-enzymatic reactions and can modulate inflammatory responses. We used a new mass spectrometry-based electrophile capture strategy to reveal the formation of electrophilic oxo-derivatives (EFOX) from the omega-3 fatty acids docosahexaenoic acid (DHA) and docosapentaenoic acid (DPA). These EFOX were generated by a cyclooxygenase-2 (COX-2)-catalyzed mechanism in activated macrophages. Modulation of COX-2 activity by aspirin increased the rate of EFOX production and their intracellular levels. Owing to their electrophilic nature, EFOX adducted to cysteine and histidine residues of proteins and activated Nrf2-dependent anti-oxidant gene expression. We confirmed the anti-inflammatory nature of DHA- and DPA-derived EFOX by showing that they can act as peroxisome proliferator-activated receptor-gamma (PPAR gamma) agonists and inhibit pro-inflammatory cytokine and nitric oxide production, all within biological concentration ranges. These data support the idea that EFOX are signaling mediators that transduce the beneficial clinical effects of omega-3 fatty acids, COX-2 and aspirin.
Assuntos
Anti-Inflamatórios/síntese química , Ciclo-Oxigenase 2/metabolismo , Ácidos Graxos Ômega-3/metabolismo , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/farmacologia , Boroidretos/farmacologia , Linhagem Celular , Membrana Celular/metabolismo , Ácidos Docosa-Hexaenoicos/química , Ácidos Docosa-Hexaenoicos/metabolismo , Ácidos Graxos Insaturados/metabolismo , Ácidos Graxos Insaturados/farmacologia , Glutationa/metabolismo , Humanos , Hidroxilação , Interleucina-10/genética , Interleucina-6/genética , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , PPAR gama/metabolismo , PPAR gama/farmacologiaRESUMO
Cigarette smoke (CS) induces oxidative stress and chronic inflammation in airway epithelium. It is a major risk factor for respiratory diseases, characterized by epithelial injury. The impact of CS on airway epithelial repair, which involves epithelial-mesenchymal transition (EMT) and the Notch-1 pathway, is incompletely understood. In this study, we used primary bronchial epithelial cells (PBECs) to evaluate the effect of CS on epithelial repair and these mechanisms. The effect of CS and/or TGF-beta1 on wound repair, various EMT and Notch-1 pathway markers and epithelial cell markers (TP63, SCGB1A) was assessed in PBECs cultured submerged, at the air-liquid interface (ALI) alone and in co-culture with fibroblasts. TGF-beta1 increased epithelial wound repair, activated EMT (shown by decrease in E-cadherin, and increases in vimentin, SNAIL1/SNAIL2/ZEB1), and increased Notch-1 pathway markers (NOTCH1/JAGGED1/HES1), MMP9, TP63, SCGB1A1. In contrast, CS decreased wound repair and vimentin, NOTCH1/JAGGED1/HES1, MMP9, TP63, SCGB1A1, whereas it activated the initial steps of the EMT (decrease in E-cadherin and increases in SNAIL1/SNAIL2/ZEB1). Using combined exposures, we observed that CS counteracted the effects of TGF-beta1. Furthermore, Notch signaling inhibition decreased wound repair. These data suggest that CS inhibits the physiological epithelial wound repair by interfering with the normal EMT process and the Notch-1 pathway.
RESUMO
Notch-1 pathway plays an important role in lung carcinoma, stem cell regulation, cellular communication, growth and differentiation. Cigarette smoke is involved in the regulation of Notch signaling. However, current data regarding the impact of cigarette smoke on the Notch pathway in lung cancer progression are limited. The present study aimed to explore whether cigarette smoke exposure altered Notch-1 pathway in ex-vivo (surgical samples of lung parenchyma from non-smoker and smoker patients with lung adenocarcinoma) and in vitro (adenocarcinoma A549 cell line) approaches. The expression of Notch-1, Jagged-1 and CD133 in surgical samples was evaluated by immunohistochemistry. A549 were exposed to cigarette smoke extracts (2.5 % and 5 % CSE for 6, 24 and 48 h) and the expression of Notch-1, Jagged-1 and Hes-1 was evaluated by Real-Time PCR and Western Blot (nuclear fractions). Expression and localization of Notch-1, Hes-1, CD133 and ABCG2 were assessed by immunofluorescence. The expression of survivin and Ki-67 was assessed by flow cytometry following CSE exposure and inhibition of Notch-1 signaling. Smokers lung parenchyma exhibited higher expression of Notch-1. CSE exposure increased Notch-1 and Hes-1 gene and nuclear protein expression in A549. Immunofluorescence confirmed higher expression of nuclear Hes-1 in CSE-stimulated A549 cells. CSE increased both survivin and Ki-67 expression and this effect was reverted by inhibition of the Notch-1 pathway. In conclusion, these data show that cigarette smoke may promote adenocarcinoma progression by activating the Notch-1 pathway thus supporting its role as hallmark of lung cancer progression and as a new target for lung cancer treatment.
Assuntos
Adenocarcinoma de Pulmão/metabolismo , Fumar Cigarros , Pulmão/metabolismo , Receptor Notch1/metabolismo , Células A549 , Antígeno AC133/genética , Antígeno AC133/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Western Blotting , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , Pulmão/efeitos dos fármacos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptor Notch1/genética , Transdução de Sinais , Fumantes , Survivina/genética , Survivina/metabolismo , Fatores de Transcrição HES-1/genética , Fatores de Transcrição HES-1/metabolismo , Regulação para CimaRESUMO
Immunoglobulin G (IgG), a type of antibody, represents approximately 75% of serum antibodies in humans, and is the most common type of antibody found in blood circulation. Consequently, the development of simple, fast and reliable systems for IgG detection, which can be achieved using electrochemical sandwich-type immunosensors, is of considerable interest. In this study we have developed an immunosensor for human (H)-IgG using an inexpensive and very simple fabrication method based on ZnO nanorods (NRs) obtained through the electrodeposition of ZnO. The ZnO NRs were treated by electrodepositing a layer of reduced graphene oxide (rGO) to ensure an easy immobilization of the antibodies. On Indium Tin Oxide supported on Polyethylene Terephthalate/ZnO NRs/rGO substrate, the sandwich configuration of the immunosensor was built through different incubation steps, which were all optimized. The immunosensor is electrochemically active thanks to the presence of gold nanoparticles tagging the secondary antibody. The immunosensor was used to measure the current density of the hydrogen development reaction which is indirectly linked to the concentration of H-IgG. In this way the calibration curve was constructed obtaining a logarithmic linear range of 10-1000 ng/mL with a detection limit of few ng/mL and good sensitivity.