RESUMEN
Airway epithelial cells (AECs) secrete innate immune cytokines that regulate adaptive immune effector cells. In allergen-sensitized humans and mice, the airway and alveolar microenvironment is enriched with colony stimulating factor-1 (CSF1) in response to allergen exposure. In this study we found that AEC-derived CSF1 had a critical role in the production of allergen reactive-IgE production. Furthermore, spatiotemporally secreted CSF1 regulated the recruitment of alveolar dendritic cells (DCs) and enhanced the migration of conventional DC2s (cDC2s) to the draining lymph node in an interferon regulatory factor 4 (IRF4)-dependent manner. CSF1 selectively upregulated the expression of the chemokine receptor CCR7 on the CSF1R+ cDC2, but not the cDC1, population in response to allergen stimuli. Our data describe the functional specification of CSF1-dependent DC subsets that link the innate and adaptive immune responses in T helper 2 (Th2) cell-mediated allergic lung inflammation.
Asunto(s)
Alérgenos/inmunología , Células Dendríticas/inmunología , Factor Estimulante de Colonias de Macrófagos/inmunología , Receptores CCR7/biosíntesis , Mucosa Respiratoria/citología , Mucosa Respiratoria/inmunología , Animales , Línea Celular , Movimiento Celular/inmunología , Células Dendríticas/clasificación , Células Epiteliales/citología , Células Epiteliales/inmunología , Humanos , Inmunidad Innata/inmunología , Inmunoglobulina E/inmunología , Factores Reguladores del Interferón/inmunología , Ganglios Linfáticos/citología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Células RAW 264.7 , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/antagonistas & inhibidores , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Células Th2/inmunología , Regulación hacia Arriba/inmunologíaRESUMEN
The prevalence of electronic cigarette (EC) use among adult with asthma has continued to increase over time, in part due to the belief of being less harmful than smoking. However, the extent of their toxicity and the involved mechanisms contributing to the deleterious impact of EC exposure on patients with preexisting asthma have not been delineated. In the present project, we tested the hypothesis that EC use contributes to respiratory damage and worsening inflammation in the lungs of patients with asthma. To define the consequences of EC exposure in established asthma, we used a mouse model with/without preexisting asthma for short-term exposure to EC aerosols. C57/BL6J mice were sensitized and challenged with a DRA (dust mite, ragweed, Aspergillus fumigates, 200 µg/mL) mixture and exposed daily to EC with nicotine (2% nicotine in 30:70 propylene glycol: vegetable glycerin) or filtered air for 2 wk. The mice were evaluated at 24 h after the final EC exposure. After EC exposure in asthmatic mice, lung inflammatory cell infiltration and goblet cell hyperplasia were increased, whereas EC alone did not cause airway inflammation. Our data also show that mitochondrial DNA (mtDNA) content and a key mtDNA regulator, mitochondrial transcription factor A (TFAM), are reduced in asthmatic EC-exposed mice in a sex-dependent manner. Together, these results indicate that TFAM loss in lung epithelium following EC contributes to male-predominant sex pathological differences, including mitochondrial damage, inflammation, and remodeling in asthmatic airways.NEW & NOTEWORTHY Respiratory immunity is dysregulated in preexisting asthma, and further perturbations by EC use could exacerbate asthma severity. However, the extent of their toxicity and the involved mechanisms contributing to the deleterious impact of EC exposure on patients with preexisting asthma have not been delineated. We found that EC has unique biological impacts in lungs and potential sex differences with loss of TFAM, a key mtDNA regulator, in lung epithelial region from our animal EC study.
Asunto(s)
Asma , Sistemas Electrónicos de Liberación de Nicotina , Neumonía , Humanos , Adulto , Masculino , Femenino , Ratones , Animales , Nicotina/toxicidad , Aerosoles y Gotitas Respiratorias , Asma/patología , Pulmón/patología , Neumonía/patología , Inflamación/patología , Modelos Animales de Enfermedad , ADN MitocondrialRESUMEN
Transcriptional profiling studies have identified several protective genes upregulated in tubular epithelial cells during acute kidney injury (AKI). Identifying upstream transcriptional regulators could lead to the development of therapeutic strategies augmenting the repair processes. SOX9 is a transcription factor controlling cell-fate during embryonic development and adult tissue homeostasis in multiple organs including the kidneys. SOX9 expression is low in adult kidneys; however, stress conditions can trigger its transcriptional upregulation in tubular epithelial cells. SOX9 plays a protective role during the early phase of AKI and facilitates repair during the recovery phase. To identify the upstream transcriptional regulators that drive SOX9 upregulation in tubular epithelial cells, we used an unbiased transcription factor screening approach. Preliminary screening and validation studies show that zinc finger protein 24 (ZFP24) governs SOX9 upregulation in tubular epithelial cells. ZFP24, a Cys2-His2 (C2H2) zinc finger protein, is essential for oligodendrocyte maturation and myelination; however, its role in the kidneys or in SOX9 regulation remains unknown. Here, we found that tubular epithelial ZFP24 gene ablation exacerbated ischemia, rhabdomyolysis, and cisplatin-associated AKI. Importantly, ZFP24 gene deletion resulted in suppression of SOX9 upregulation in injured tubular epithelial cells. Chromatin immunoprecipitation and promoter luciferase assays confirmed that ZFP24 bound to a specific site in both murine and human SOX9 promoters. Importantly, CRISPR/Cas9-mediated mutation in the ZFP24 binding site in the SOX9 promoter in vivo led to suppression of SOX9 upregulation during AKI. Thus, our findings identify ZFP24 as a critical stress-responsive transcription factor protecting tubular epithelial cells through SOX9 upregulation.
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Lesión Renal Aguda , Factor de Transcripción SOX9 , Animales , Humanos , Ratones , Lesión Renal Aguda/prevención & control , Células Epiteliales/metabolismo , Riñón/metabolismo , Factor de Transcripción SOX9/genética , Factor de Transcripción SOX9/metabolismo , Regulación hacia Arriba , Dedos de ZincRESUMEN
Damage associated molecular patterns (DAMPs) are molecules released from dead/dying cells following toxicant and/or environmental exposures that activate the immune response through binding of pattern recognition receptors (PRRs). Excessive production of DAMPs or failed clearance leads to chronic inflammation and delayed inflammation resolution. One category of DAMPs are oxidized phospholipids (oxPLs) produced upon exposure to high levels of oxidative stress, such as following ozone (O3) induced inflammation. OxPLs are bound by multiple classes of PRRs that include scavenger receptors (SRs) such as SR class B-1 (SR-BI) and toll-like receptors (TLRs). Interactions between oxPLs and PRRs appear to regulate inflammation; however, the role of SR-BI in oxPL-induced lung inflammation has not been defined. Therefore, we hypothesize that SR-BI is critical in protecting the lung from oxPL-induced pulmonary inflammation/injury. To test this hypothesis, C57BL/6J (WT) female mice were dosed with oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphatidylcholine (oxPAPC) by oropharyngeal aspiration which increased pulmonary SR-BI expression. Following oxPAPC exposure, SR-BI deficient (SR-BI-/-) mice exhibited increased lung pathology and inflammatory cytokine/chemokine production. Lipidomic analysis revealed that SR-BI-/- mice had an altered pulmonary lipidome prior to and following oxPAPC exposure, which correlated with increased oxidized phosphatidylcholines (PCs). Finally, we characterized TLR4-mediated activation of NF-κB following oxPAPC exposure and discovered that SR-BI-/- mice had increased TLR4 mRNA expression in lung tissue and macrophages, increased nuclear p65, and decreased cytoplasmic IκBα. Overall, we conclude that SR-BI is required for limiting oxPAPC-induced lung pathology by maintaining lipid homeostasis, reducing oxidized PCs, and attenuating TLR4-NF-κB activation, thereby preventing excessive and persistent inflammation.
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Fosfolípidos , Neumonía , Animales , Femenino , Ratones , Proteínas Portadoras , Inflamación/inducido químicamente , Ratones Endogámicos C57BL , FN-kappa B/metabolismo , Neumonía/inducido químicamente , Neumonía/prevención & control , Receptores Depuradores/genética , Receptores Depuradores/metabolismo , Receptor Toll-Like 4/metabolismoRESUMEN
INTRODUCTION: Although the greater popularity of electronic cigarettes (EC) among asthmatics is alarming, there is limited knowledge of the long-term consequences of EC exposure in asthmatics. AIMS AND METHODS: Mild asthmatic C57/BL6J adult male and female mice were established by intranasal insufflation with three combined allergens. The asthmatic and age and sex-matched' naïve mice were exposed to air, nicotine-free (propylene glycol [PG]/vegetable glycerin [VG]-only), or PG/VG+Nicotine, 4 hours daily for 3 months. The effects of EC exposure were accessed by measuring cytokines in bronchoalveolar lavage, periodic acid-schiff (PAS) staining, mitochondrial DNA copy numbers (mtCN), and the transcriptome in the lung. Significance was false discovery rate <0.2 for transcriptome and 0.05 for the others. RESULTS: In asthmatic mice, PG/VG+Nicotine increased PAS-positive cells and IL-13 compared to mice exposed to air and PG/VG-only. In naïve mice exposed to PG/VG+Nicotine and PG/VG-only, higher INF-γ was observed compared to mice exposed only to air. PG/VG-only and PG/VG+Nicotine had significantly higher mtCN compared to air exposure in asthmatic mice, while the opposite pattern was observed in non-asthmatic naïve mice. Different gene expression patterns were profoundly found for asthmatic mice exposed to PG/VG+Nicotine compared to PG/VG-only, including genes involved in mitochondrial dysfunction, oxidative phosphorylation, and p21-activated kinase (PAK) signaling. CONCLUSIONS: This study provides experimental evidence of the potential impact of nicotine enhancement on the long-term effects of EC in asthmatics compared to non-asthmatics. IMPLICATIONS: The findings from this study indicate the potential impact of EC in asthmatics by addressing multiple biological markers. The long-term health outcomes of EC in the susceptible group can be instrumental in supporting policymaking and educational campaigns and informing the public, healthcare providers, and EC users about the underlying risks of EC use.
Asunto(s)
Asma , Sistemas Electrónicos de Liberación de Nicotina , Masculino , Ratones , Femenino , Animales , Nicotina/efectos adversos , Asma/etiología , Pulmón , Propilenglicol/farmacología , Glicerol/farmacología , VerdurasRESUMEN
Idiopathic pulmonary fibrosis is a deadly disease characterized by excessive extracellular matrix deposition in the lungs, resulting in decreased pulmonary function. Although epithelial cells and fibroblasts have long been the focus of idiopathic pulmonary fibrosis research, the role of various subpopulations of macrophages in promoting a fibrotic response is an emerging target. Healthy lungs are composed of two macrophage populations, tissue-resident alveolar macrophages and interstitial macrophages, which help to maintain homeostasis. After injury, tissue-resident alveolar macrophages are depleted, and monocytes from the bone marrow (BM) traffic to the lungs along a CCL2/CCR2 axis and differentiate into monocyte-derived alveolar macrophages (Mo-AMs), which is a cell population implicated in murine models of pulmonary fibrosis. In this study, we sought to determine how IL-1R-associated kinase-M (IRAK-M), a negative regulator of TLR signaling, modulates monocyte trafficking into the lungs in response to bleomycin. Our data indicate that after bleomycin challenge, mice lacking IRAK-M have decreased monocyte trafficking and reduced Mo-AMs in their lungs. Although IRAK-M expression did not regulate differences in chemokines, cytokines, or adhesion molecules associated with monocyte recruitment, IRAK-M was necessary for CCR2 upregulation following bleomycin challenge. This finding prompted us to develop a competitive BM chimera model, which demonstrated that expression of BM-derived IRAK-M was necessary for monocyte trafficking into the lung and for subsequent enhanced collagen deposition. These data indicate that IRAK-M regulates monocyte trafficking by increasing the expression of CCR2, resulting in enhanced monocyte translocation into the lung, Mo-AM differentiation, and development of pulmonary fibrosis.
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Antibacterianos/uso terapéutico , Bleomicina/uso terapéutico , Fibrosis Pulmonar Idiopática/tratamiento farmacológico , Quinasas Asociadas a Receptores de Interleucina-1/metabolismo , Monocitos/inmunología , Animales , Movimiento Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Humanos , Fibrosis Pulmonar Idiopática/inmunología , Quinasas Asociadas a Receptores de Interleucina-1/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Monocitos/efectos de los fármacos , Receptores CCR2/metabolismo , Transducción de Señal , Regulación hacia ArribaRESUMEN
The incidence of asthma has increased from 5.5% to near 8% of the population, which is a major health concern. The hallmarks of asthma include eosinophilic airway inflammation that is associated with chronic airway remodeling. Allergic airway inflammation is characterized by a complex interplay of resident and inflammatory cells. MicroRNAs (miRNAs) are small noncoding RNAs that function as posttranscriptional modulators of gene expression. However, the role of miRNAs, specifically miR-451, in the regulation of allergic airway inflammation is unexplored. Our previous findings showed that oxidant stress regulates miR-451 gene expression in macrophages during an inflammatory process. In this paper, we examined the role of miR-451 in regulating macrophage phenotype using an experimental poly-allergenic murine model of allergic airway inflammation. We found that miR-451 contributes to the allergic induction of CCL17 in the lung and plays a key role in proasthmatic macrophage activation. Remarkably, administration of a Sirtuin 2 (Sirt2) inhibitor diminished alternate macrophage activation and markedly abrogated triple-allergen [dust mite, ragweed, Aspergillus fumigatus (DRA)]-induced lung inflammation. These data demonstrate a role for miR-451 in modulating allergic inflammation by influencing allergen-mediated macrophages phenotype.
Asunto(s)
Asma/genética , Macrófagos Alveolares/inmunología , MicroARNs/genética , Neumonía/genética , Sirtuina 2/genética , Alérgenos/administración & dosificación , Animales , Antiinflamatorios/farmacología , Antígenos de Plantas/administración & dosificación , Aspergillus/química , Aspergillus/inmunología , Asma/inducido químicamente , Asma/patología , Asma/terapia , Quimiocina CCL17/genética , Quimiocina CCL17/inmunología , Modelos Animales de Enfermedad , Hongos/química , Hongos/inmunología , Furanos/farmacología , Regulación de la Expresión Génica , Pulmón/efectos de los fármacos , Pulmón/inmunología , Pulmón/patología , Activación de Macrófagos/efectos de los fármacos , Macrófagos Alveolares/efectos de los fármacos , Macrófagos Alveolares/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , MicroARNs/inmunología , Extractos Vegetales/administración & dosificación , Neumonía/inducido químicamente , Neumonía/patología , Neumonía/terapia , Pyroglyphidae/química , Pyroglyphidae/inmunología , Quinolinas/farmacología , Transducción de Señal , Sirtuina 2/antagonistas & inhibidores , Sirtuina 2/inmunologíaRESUMEN
BACKGROUND: The pathogenesis of asthma and airway obstruction is the result of an abnormal response to different environmental exposures. The scientific premise of our study was based on the finding that FoxO1 expression is increased in lung macrophages of mice after allergen exposure and human asthmatic patients. Macrophages are capable of switching from one functional phenotype to another, and it is important to understand the mechanisms involved in the transformation of macrophages and how their cellular function affects the peribronchial stromal microenvironment. METHODS: We employed a murine asthma model, in which mice were treated by intranasal insufflation with allergens for 2-8 weeks. We used both a pharmacologic approach using a highly specific FoxO1 inhibitor and genetic approaches using FoxO1 knockout mice (FoxO1fl/fl LysMcre). Cytokine level in biological fluids was measured by ELISA and the expression of encoding molecules by NanoString assay and qRT-PCR. RESULTS: We show that the levels of FoxO1 gene are significantly elevated in the airway macrophages of patients with mild asthma in response to subsegmental bronchial allergen challenge. Transcription factor FoxO1 regulates a pro-asthmatic phenotype of lung macrophages that is involved in the development and progression of chronic allergic airway disease. We have shown that inhibition of FoxO1 induced phenotypic conversion of lung macrophages and downregulates pro-asthmatic and pro-fibrotic gene expression by macrophages, which contribute to airway inflammation and airway remodeling in allergic asthma. CONCLUSION: Targeting FoxO1 with its downstream regulator IRF4 is a novel therapeutic target for controlling allergic inflammation and potentially reversing fibrotic airway remodeling.
Asunto(s)
Asma/etiología , Asma/metabolismo , Proteína Forkhead Box O1/genética , Regulación Neoplásica de la Expresión Génica , Activación de Macrófagos/inmunología , Macrófagos/inmunología , Macrófagos/metabolismo , Traslado Adoptivo , Alérgenos/inmunología , Animales , Asma/diagnóstico , Asma/terapia , Pruebas de Provocación Bronquial , Broncoscopía , Modelos Animales de Enfermedad , Femenino , Citometría de Flujo , Proteína Forkhead Box O1/metabolismo , Humanos , Ratones , Células Th2/inmunología , Células Th2/metabolismoRESUMEN
Although alveolar macrophages (AMs) from patients with asthma are known to be functionally different from those of healthy individuals, the mechanism by which this transformation occurs has not been fully elucidated in asthma. The goal of this study was to define the mechanisms that control AM phenotypic and functional transformation in response to acute allergic airway inflammation. The phenotype and functional characteristics of AMs obtained from human subjects with asthma after subsegmental bronchoprovocation with allergen was studied. Using macrophage-depleted mice, the role and trafficking of AM populations was determined using an acute allergic lung inflammation model. We observed that depletion of AMs in a mouse allergic asthma model attenuates Th2-type allergic lung inflammation and its consequent airway remodeling. In both human and mouse, endobronchial challenge with allergen induced a marked increase in monocyte chemotactic proteins (MCPs) in bronchoalveolar fluid, concomitant with the rapid appearance of a monocyte-derived population of AMs. Furthermore, airway allergen challenge of allergic subjects with mild asthma skewed the pattern of AM gene expression toward high levels of the receptor for MCP1 (CCR2/MCP1R) and expression of M2 phenotypic proteins, whereas most proinflammatory genes were highly suppressed. CCL2/MCP-1 gene expression was prominent in bronchial epithelial cells in a mouse allergic asthma model, and in vitro studies indicate that bronchial epithelial cells produced abundant MCP-1 in response to house dust mite allergen. Thus, our study indicates that bronchial allergen challenge induces the recruitment of blood monocytes along a chemotactic gradient generated by allergen-exposed bronchial epithelial cells.
Asunto(s)
Remodelación de las Vías Aéreas (Respiratorias)/inmunología , Asma/inmunología , Quimiocina CCL2/fisiología , Macrófagos Alveolares/inmunología , Animales , Antígenos Dermatofagoides/inmunología , Asma/metabolismo , Línea Celular , Quimiotaxis , Femenino , Humanos , Masculino , Ratones Endogámicos C57BL , Pyroglyphidae/inmunología , TranscriptomaRESUMEN
RATIONALE: Bioactive lipid mediators, derived from membrane lipid precursors, are released into the airway and airspace where they bind high-affinity cognate receptors and may mediate asthma pathogenesis. Lysophosphatidic acid (LPA), a bioactive lipid mediator generated by the enzymatic activity of extracellular autotaxin (ATX), binds LPA receptors, resulting in an array of biological actions on cell proliferation, migration, survival, differentiation, and motility, and therefore could mediate asthma pathogenesis. OBJECTIVES: To define a role for the ATX-LPA pathway in human asthma pathogenesis and a murine model of allergic lung inflammation. METHODS: We investigated the profiles of LPA molecular species and the level of ATX exoenzyme in bronchoalveolar lavage fluids of human patients with asthma subjected to subsegmental bronchoprovocation with allergen. We interrogated the role of the ATX-LPA pathway in allergic lung inflammation using a murine allergic asthma model in ATX-LPA pathway-specific genetically modified mice. MEASUREMENTS AND MAIN RESULTS: Subsegmental bronchoprovocation with allergen in patients with mild asthma resulted in a remarkable increase in bronchoalveolar lavage fluid levels of LPA enriched in polyunsaturated 22:5 and 22:6 fatty acids in association with increased concentrations of ATX protein. Using a triple-allergen mouse asthma model, we showed that ATX-overexpressing transgenic mice had a more severe asthmatic phenotype, whereas blocking ATX activity and knockdown of the LPA2 receptor in mice produced a marked attenuation of Th2 cytokines and allergic lung inflammation. CONCLUSIONS: The ATX-LPA pathway plays a critical role in the pathogenesis of asthma. These preclinical data indicate that targeting the ATX-LPA pathway could be an effective antiasthma treatment strategy.
Asunto(s)
Asma/fisiopatología , Inflamación/fisiopatología , Lisofosfolípidos/fisiología , Hidrolasas Diéster Fosfóricas/fisiología , Alérgenos/farmacología , Animales , Asma/inducido químicamente , Asma/etiología , Líquido del Lavado Bronquioalveolar/química , Modelos Animales de Enfermedad , Humanos , Inflamación/etiología , Masculino , Ratones , Ratones Transgénicos , Hidrolasas Diéster Fosfóricas/análisis , Transducción de Señal/fisiologíaRESUMEN
Our previous research demonstrated that PU.1 regulates expression of the genes involved in inflammation in macrophages. Selective knockdown of PU.1 in macrophages ameliorated LPS-induced acute lung injury (ALI) in bone marrow chimera mice. Inhibitors that block the transcriptional activity of PU.1 in macrophages have the potential to mitigate the pathophysiology of LPS-induced ALI. However, complete inactivation of PU.1 gene disrupts normal myelopoiesis. Although the green tea polyphenol Epigallocatechin gallate (EGCG) has been shown to regulate inflammatory genes in various cell types, it is not known if EGCG alters the transcriptional activity of PU.1 protein. Using Schrodinger Glide docking, we have identified that EGCG binds with PU.1 protein, altering its DNA-binding and self-dimerization activity. In silico analysis shows that EGCG forms Hydrogen bonds with Glutamic Acid 209, Leucine 250 in DNA binding and Lysine 196, Tryptophan 193, and Leucine 182 in the self-dimerization domain of the PU.1 protein. Experimental validation using mouse bone marrow-derived macrophages (BMDM) confirmed that EGCG inhibits both DNA binding by PU.1 and self-dimerization. Importantly, EGCG had no impact on expression of the total PU.1 protein levels but significantly reduced expression of various inflammatory genes and generation of ROS. In summary, we report that EGCG acts as an inhibitor of the PU.1 transcription factor in macrophages.
Asunto(s)
Catequina , Catequina/análogos & derivados , Macrófagos , Proteínas Proto-Oncogénicas , Transactivadores , Catequina/farmacología , Animales , Transactivadores/metabolismo , Transactivadores/genética , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas/genética , Ratones , Ratones Endogámicos C57BL , Simulación del Acoplamiento Molecular , Unión Proteica , ADN/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Lipopolisacáridos/farmacologíaRESUMEN
Extracellular vesicles mediate intercellular communication by transporting biologically active macromolecules. Our prior studies have demonstrated that the nuclear factor of activated T cell cytoplasmic member 3 (NFATc3) is activated in mouse pulmonary macrophages in response to lipopolysaccharide (LPS). Inhibition of NFATc3 activation by a novel cell-permeable calcineurin peptide inhibitor CNI103 mitigated the development of acute lung injury (ALI) in LPS-treated mice. Although pro-inflammatory lipid mediators are known contributors to lung inflammation and injury, it remains unclear whether the calcineurin-NFATc pathway regulates extracellular vesicle (EV) lipid content and if this content contributes to ALI pathogenesis. In this study, EVs from mouse bronchoalveolar lavage fluid (BALF) were analyzed for their lipid mediators by liquid chromatography in conjunction with mass spectrometry (LC-MS/MS). Our data demonstrate that EVs from LPS-treated mice contained significantly higher levels of arachidonic acid (AA) metabolites, which were found in low levels by prior treatment with CNI103. The catalytic activity of lung tissue cytoplasmic phospholipase A2 (cPLA2) increased during ALI, correlating with an increased amount of arachidonic acid (AA) in the EVs. Furthermore, ALI is associated with increased expression of cPLA2, cyclooxygenase 2 (COX2), and lipoxygenases (5-LOX, 12-LOX, and 15-LOX) in lung tissue, and pretreatment with CNI103 inhibited the catalytic activity of cPLA2 and the expression of cPLA2, COX, and LOX transcripts. Furthermore, co-culture of mouse pulmonary microvascular endothelial cell (PMVEC) monolayer and NFAT-luciferase reporter macrophages with BALF EVs from LPS-treated mice increased the pulmonary microvascular endothelial cell (PMVEC) monolayer barrier permeability and luciferase activity in macrophages. However, EVs from CNI103-treated mice had no negative impact on PMVEC monolayer barrier integrity. In summary, BALF EVs from LPS-treated mice carry biologically active NFATc-dependent, AA-derived lipids that play a role in regulating PMVEC monolayer barrier function.
RESUMEN
Forkhead box class O 3a (FOXO3) is a member of the FoxO transcription factor subfamily, which regulates the expression of target genes not only through DNA binding as a transcription factor, but also through protein-protein interaction. Although FoxO3 is a well-known transcription factor involved in diverse biological processes, the role of FoxO3 in cigarette smoke (CS)-induced lung inflammation and injury has not been studied. It is, therefore, hypothesized that deficiency of FoxO3 leads to increased susceptibility to CS-induced lung inflammatory response and airspace enlargement. In this article, we show that the levels of FOXO3 are significantly decreased in lungs of smokers and patients with chronic obstructive pulmonary disease, as well as in lungs of mice exposed to CS. Genetic ablation of FoxO3 led to pulmonary emphysema and exaggerated inflammatory response in lungs of mice exposed to CS. We further showed that CS induced the translocation of FoxO3 into the nucleus where FoxO3 interacted with NF-κB and disrupted NF-κB DNA-binding ability, leading to inhibition of its activity. Targeted disruption of FoxO3 also resulted in downregulation of antioxidant genes in mouse lungs in response to CS exposure. These results suggest that FoxO3 plays a pivotal role in regulation of lung inflammatory response and antioxidant genes, and deficiency of FoxO3 results in development of chronic obstructive pulmonary disease/emphysema.
Asunto(s)
Factores de Transcripción Forkhead/deficiencia , Predisposición Genética a la Enfermedad , Enfermedad Pulmonar Obstructiva Crónica/inmunología , Enfermedad Pulmonar Obstructiva Crónica/patología , Enfisema Pulmonar/inmunología , Enfisema Pulmonar/patología , Fumar/inmunología , Fumar/patología , Animales , Regulación hacia Abajo/genética , Regulación hacia Abajo/inmunología , Proteína Forkhead Box O3 , Factores de Transcripción Forkhead/antagonistas & inhibidores , Factores de Transcripción Forkhead/genética , Humanos , Inflamación/genética , Inflamación/inmunología , Inflamación/patología , Pulmón/inmunología , Pulmón/metabolismo , Pulmón/patología , Ratones , Ratones de la Cepa 129 , Ratones Noqueados , Ratones Transgénicos , Enfermedad Pulmonar Obstructiva Crónica/genética , Enfisema Pulmonar/genética , Fumar/genéticaRESUMEN
Extracellular superoxide dismutase (ECSOD or SOD3) is highly expressed in lungs and functions as a scavenger of O(2)(*-). ECM fragmentation, which can be triggered by oxidative stress, participates in the pathogenesis of chronic obstructive pulmonary disease (COPD) through attracting inflammatory cells into the lungs. The level of SOD3 is significantly decreased in lungs of patients with COPD. However, the role of endogenous SOD3 in the development/progression of emphysema is unknown. We hypothesized that SOD3 protects against emphysema by attenuating oxidative fragmentation of ECM in mice. To test this hypothesis, SOD3-deficient, SOD3-transgenic, and WT C57BL/6J mice were exposed to cigarette smoke (CS) for 3 d (300 mg total particulate matter/m(3)) to 6 mo (100 mg/m(3) total particulate matter) or by intratracheal elastase injection. Airspace enlargement, lung inflammation, lung mechanical properties, and exercise tolerance were determined at different time points during CS exposure or after elastase administration. CS exposure and elastase administration caused airspace enlargement as well as impaired lung function and exercise capacity in SOD3-null mice, which were improved in mice overexpressing SOD3 and by pharmacological SOD mimetic. These phenomena were associated with SOD3-mediated protection against oxidative fragmentation of ECM, such as heparin sulfate and elastin, thereby attenuating lung inflammatory response. In conclusion, SOD3 attenuates emphysema and reduces oxidative fragmentation of ECM in mouse lung. Thus, pharmacological augmentation of SOD3 in the lung may have a therapeutic potential in the intervention of COPD/emphysema.
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Matriz Extracelular/metabolismo , Estrés Oxidativo , Enfisema Pulmonar/enzimología , Superóxido Dismutasa/metabolismo , Animales , Líquido del Lavado Bronquioalveolar/citología , Elastina/metabolismo , Heparitina Sulfato/metabolismo , Immunoblotting , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pulmón/fisiopatología , Rendimiento Pulmonar/efectos de los fármacos , Metaloporfirinas/administración & dosificación , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Neutrófilos/citología , Neutrófilos/efectos de los fármacos , Elastasa Pancreática/administración & dosificación , Enfisema Pulmonar/genética , Enfisema Pulmonar/fisiopatología , Humo , Superóxido Dismutasa/genética , Porcinos , Factores de Tiempo , Nicotiana/químicaRESUMEN
Asthma is phenotypically heterogeneous with several distinctive pathological mechanistic pathways. Previous studies indicate that neutrophilic asthma has a poor response to standard asthma treatments comprising inhaled corticosteroids. Therefore, it is important to identify critical factors that contribute to increased numbers of neutrophils in asthma patients whose symptoms are poorly controlled by conventional therapy. Leukocytes release chromatin fibers, referred to as extracellular traps (ETs) consisting of double-stranded (ds) DNA, histones, and granule contents. Excessive components of ETs contribute to the pathophysiology of asthma; however, it is unclear how ETs drive asthma phenotypes and whether they could be a potential therapeutic target. We employed a mouse model of severe asthma that recapitulates the intricate immune responses of neutrophilic and eosinophilic airway inflammation identified in patients with severe asthma. We used both a pharmacologic approach using miR-155 inhibitor-laden exosomes and genetic approaches using miR-155 knockout mice. Our data show that ETs are present in the bronchoalveolar lavage fluid of patients with mild asthma subjected to experimental subsegmental bronchoprovocation to an allergen and a severe asthma mouse model, which resembles the complex immune responses identified in severe human asthma. Furthermore, we show that miR-155 contributes to the extracellular release of dsDNA, which exacerbates allergic lung inflammation, and the inhibition of miR-155 results in therapeutic benefit in severe asthma mice. Our findings show that targeting dsDNA release represents an attractive therapeutic target for mitigating neutrophilic asthma phenotype, which is clinically refractory to standard care.
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Asma , Eosinofilia , MicroARNs , Neumonía , Animales , Modelos Animales de Enfermedad , Granulocitos , Humanos , Ratones , MicroARNs/metabolismo , Neutrófilos , Neumonía/tratamiento farmacológico , Neumonía/metabolismoRESUMEN
BACKGROUND: Mitochondrial DNA copy number (mtCN) maintains cellular function and homeostasis, and is linked to nuclear DNA methylation and gene expression. Increased mtCN in the blood is associated with smoking and respiratory disease, but has received little attention for target organ effects for smoking or electronic cigarette (EC) use. METHODS: Bronchoscopy biospecimens from healthy EC users, smokers (SM), and never-smokers (NS) were assessed for associations of mtCN with mtDNA point mutations, immune responses, nuclear DNA methylation and gene expression using linear regression. Ingenuity pathway analysis was used for enriched pathways. GEO and TCGA respiratory disease datasets were used to explore the involvement of mtCN-associated signatures. FINDINGS: mtCN was higher in SM than NS, but EC was not statistically different from either. Overall there was a negative association of mtCN with a point mutation in the D-loop but no difference within groups. Positive associations of mtCN with IL-2 and IL-4 were found in EC only. mtCN was significantly associated with 71,487 CpGs and 321 transcripts. 263 CpGs were correlated with nearby transcripts for genes enriched in the immune system. EC-specific mtCN-associated-CpGs and genes were differentially expressed in respiratory diseases compared to controls, including genes involved in cellular movement, inflammation, metabolism, and airway hyperresponsiveness. INTERPRETATION: Smoking may elicit a lung toxic effect through mtCN. While the impact of EC is less clear, EC-specific associations of mtCN with nuclear biomarkers suggest exposure may not be harmless. Further research is needed to understand the role of smoking and EC-related mtCN on lung disease risks. FUNDING: The National Cancer Institute, the National Heart, Lung, and Blood Institute, the Food and Drug Administration Center for Tobacco Products, the National Center For Advancing Translational Sciences, and Pelotonia Intramural Research Funds.
Asunto(s)
ADN Mitocondrial , Sistemas Electrónicos de Liberación de Nicotina , Humanos , ADN Mitocondrial/genética , Fumadores , Variaciones en el Número de Copia de ADN , Biomarcadores , Metilación de ADN , Pulmón , Transcripción GenéticaRESUMEN
Emerging data support the pivotal role of extracellular vesicles (EVs) in normal cellular physiology and disease conditions. However, despite their abundance, there is much less information about the lipid mediators carried in EVs, especially in the context of acute lung injury (ALI). Our data demonstrate that C57BL/6 mice subjected to intranasal Escherichia coli lipopolysaccharide (LPS)-induced ALI release, a higher number of EVs into the alveolar space, compared to saline-treated controls. EVs released during ALI originated from alveolar epithelial cells, macrophages, and neutrophils and carry a diverse array of lipid mediators derived from ω-3 and ω-6 polyunsaturated fatty acids (PUFA). The eicosanoids in EVs correlated with cellular levels of arachidonic acid, expression of cytosolic phospholipase A2, cyclooxygenase (COX), lipoxygenase (LOX), and cytochrome epoxygenase p450 proteins in pulmonary macrophages. Furthermore, EVs from LPS-toll-like receptor 4 knockout (TLR4-/-) mice contained significantly lower amounts of COX and LOX catalyzed eicosanoids and ω-3 PUFA metabolites. More importantly, EVs from LPS-treated wild-type mice increased TNF-α release by macrophages and reduced alveolar epithelial monolayer barrier integrity compared to EVs from LPS-treated TLR4-/- mice. In summary, our study demonstrates for the first time that the EV carried PUFA metabolite profile in part depends on the inflammatory status of the lung macrophages and modulates pulmonary macrophage and alveolar epithelial cell function during LPS-induced ALI.
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Lesión Pulmonar Aguda , Vesículas Extracelulares , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/metabolismo , Animales , Líquido del Lavado Bronquioalveolar , Vesículas Extracelulares/metabolismo , Lipidómica , Lipopolisacáridos/farmacología , Pulmón/metabolismo , Ratones , Ratones Endogámicos C57BL , Receptor Toll-Like 4/metabolismoRESUMEN
Sirtuin1 (SIRT1) deacetylase levels are decreased in chronic inflammatory conditions and aging where oxidative stress occurs. We determined the mechanism of SIRT1 redox post-translational modifications leading to its degradation. Human lung epithelial cells exposed to hydrogen peroxide (150-250 microM), aldehyde-acrolein (10-30 microM), and cigarette smoke extract (CSE; 0.1-1.5%) in the presence of intracellular glutathione-modulating agents at 1-24 h, and oxidative post-translational modifications were assayed in cells, as well as in lungs of mice lacking and overexpressing glutaredoxin-1 (Glrx1), and wild-type (WT) mice in response to cigarette smoke (CS). CSE and aldehydes dose and time dependently decreased SIRT1 protein levels, with EC(50) of 1% for CSE and 30 microM for acrolein at 6 h, and >80% inhibition at 24 h with CSE, which was regulated by modulation of intracellular thiol status of the cells. CS decreased the lung levels of SIRT1 in WT mice, which was enhanced by deficiency of Glrx1 and prevented by overexpression of Glrx1. Oxidants, aldehydes, and CS induced carbonyl modifications on SIRT1 on cysteine residues concomitant with decreased SIRT1 activity. Proteomics studies revealed alkylation of cysteine residue on SIRT1. Our data suggest that oxidants/aldehydes covalently modify SIRT1, decreasing enzymatic activity and marking the protein for proteasomal degradation, which has implications in inflammatory conditions.
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Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Nicotiana/efectos adversos , Oxidantes/farmacología , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Sirtuina 1/metabolismo , Humo/efectos adversos , Acroleína/farmacología , Animales , Línea Celular , Glutarredoxinas/metabolismo , Humanos , Peróxido de Hidrógeno/farmacología , Immunoblotting , Masculino , Ratones , Ratones Endogámicos C57BL , Oxidación-Reducción/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Carbonilación Proteica/efectos de los fármacos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
Pulmonary macrophages play a critical role in the recognition of pathogens, initiation of host defense via inflammation, clearance of pathogens from the airways, and resolution of inflammation. Recently, we have shown a pivotal role for the nuclear factor of activated T-cell cytoplasmic member 3 (NFATc3) transcription factor in modulating pulmonary macrophage function in LPS-induced acute lung injury (ALI) pathogenesis. Although the NFATc proteins are activated primarily by calcineurin-dependent dephosphorylation, here we show that LPS induces posttranslational modification of NFATc3 by polyADP-ribose polymerase 1 (PARP-1)-mediated polyADP-ribosylation. ADP-ribosylated NFATc3 showed increased binding to iNOS and TNFα promoter DNA, thereby increasing downstream gene expression. Inhibitors of PARP-1 decreased LPS-induced NFATc3 ribosylation, target gene promoter binding, and gene expression. LPS increased NFAT luciferase reporter activity in lung macrophages and lung tissue that was inhibited by pretreatment with PARP-1 inhibitors. More importantly, pretreatment of mice with the PARP-1 inhibitor olaparib markedly decreased LPS-induced cytokines, protein extravasation in bronchoalveolar fluid, lung wet-to-dry ratios, and myeloperoxidase activity. Furthermore, PARP-1 inhibitors decreased NF-кB luciferase reporter activity and LPS-induced ALI in NF-кB reporter mice. Thus, our study demonstrates that inhibiting NFATc3 and NF-кB polyADP-ribosylation with PARP-1 inhibitors prevented LPS-induced ALI pathogenesis.
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Lesión Pulmonar Aguda/metabolismo , Inflamación/genética , Pulmón/inmunología , Macrófagos/inmunología , FN-kappa B/metabolismo , Factores de Transcripción NFATC/metabolismo , Edema Pulmonar/inmunología , Lesión Pulmonar Aguda/inmunología , Animales , Células Cultivadas , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Humanos , Lipopolisacáridos/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Poli ADP RibosilaciónRESUMEN
Tumor suppressive microRNAs (miRNAs) are increasingly implicated in the development of anti-tumor therapy by reprogramming gene network that are aberrantly regulated in cancer cells. This study aimed to determine the therapeutic potential of putative tumor suppressive miRNA, miR-138, against glioblastoma (GBM). Whole transcriptome and miRNA expression profiling analyses on human GBM patient tissues identified miR-138 as one of the significantly downregulated miRNAs with an inverse correlation with CD44 expression. Transient overexpression of miR-138 in GBM cells inhibited cell proliferation, cell cycle, migration, and wound healing capability. We unveiled that miR-138 negatively regulates the expression of CD44 by directly binding to the 3' UTR of CD44. CD44 inhibition by miR-138 resulted in an inhibition of glioblastoma cell proliferation in vitro through cell cycle arrest as evidenced by a significant induction of p27 and its translocation into nucleus. Ectopic expression of miR-138 also increased survival rates in mice that had an intracranial xenograft tumor derived from human patient-derived primary GBM cells. In conclusion, we demonstrated a therapeutic potential of tumor suppressive miR-138 through direct downregulation of CD44 for the treatment of primary GBM.