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BACKGROUND: Studies on the association between preserved ratio impaired spirometry (PRISm) and dementia are limited. Indeed, PRISm has often been overlooked or ignored as an index of lung function impairment. Therefore, we investigated the association of PRISm with the risk for the development of dementia in an older Japanese population. METHODS: A total of 1202 community-dwelling, older Japanese participants aged ≥65 years without dementia were followed up for a median of 5.0 years. Participants were categorized by spirometry as follows: normal spirometry (FEV1/FVC ≥0.70 and FEV1 ≥80% predicted), PRISm (≥0.70 and <80%), airflow limitation (AFL) Global Initiative for Chronic Obstructive Lung Disease (GOLD) 1 (<0.70 and ≥80%), and AFL GOLD 2 to 4 (<0.70 and <80%). Hazard ratios (HRs) and their 95% confidence intervals (CIs) were computed using a Cox proportional hazards model. RESULTS: During the follow-up period, 122 participants developed dementia. The age- and sex-adjusted incidences of dementia in the participants with normal spirometry, PRISm, AFL GOLD 1, and AFL GOLD 2 to 4 were 20.5, 37.0, 18.4, and 28.6 per 1000 person-years, respectively. Participants with PRISm had a higher risk of dementia (HR 2.04 [95%CI, 1.19-3.49]) than those with normal spirometry after adjusting for confounders. Moreover, both reduced FEV1% predicted values and FVC% predicted values were associated with the risk for dementia. CONCLUSION: PRISm was associated with an increased risk of dementia in a general older Japanese population.
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Rationale: Several Western studies have reported that participants with preserved ratio impaired spirometry (PRISm) have higher risks of airflow limitation (AFL) and death. However, evidence in East Asian populations is limited. Objectives: To investigate the relationship between PRISm and the risks of death and incident AFL in a Japanese population. Methods: A total of 3,032 community-dwelling Japanese participants aged ⩾40 years were seen in follow-up for a median of 5.3 years by annual spirometry examinations. Participants were classified into lung function categories at baseline as follows: normal spirometry (FEV1/FVC ⩾0.70 and FEV1 ⩾80% predicted), PRISm (⩾0.70 and <80%), AFL Global Initiative for Chronic Obstructive Lung Disease 1 (<0.70 and ⩾80%), and AFL Global Initiative for Chronic Obstructive Lung Disease 2-4 (<0.70 and <80%). Hazard ratios (HRs) and their 95% confidence intervals were computed using a Cox proportional hazards model. Measurements and Main Results: During the follow-up period, 131 participants died, 22 of whom died of cardiovascular disease, and 218 participants developed AFL. When examining the prognosis of each baseline lung function category, participants with PRISm had higher risks of all-cause death (HR, 2.20; 95% confidence interval, 1.35-3.59) and cardiovascular death (HR, 4.07; 1.07-15.42) than those with normal spirometry after adjusting for confounders. Moreover, the multivariable-adjusted risk of incident AFL was greater in participants with PRISm than in those with normal spirometry (HR, 2.48; 1.83-3.36). Conclusions: PRISm was associated with higher risks of all-cause and cardiovascular death and a greater risk of the development of AFL in a Japanese community.
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Pulmão , Doença Pulmonar Obstrutiva Crônica , Idoso , Volume Expiratório Forçado , Humanos , Japão/epidemiologia , Testes de Função Respiratória , Fatores de Risco , Espirometria , Capacidade VitalRESUMO
BACKGROUND: Airway epithelial barrier function is maintained by the formation of tight junctions (TJs) and adherens junctions (AJs). Inhalation of cigarette smoke causes airway epithelial barrier dysfunction and may contribute to the pathogenesis of chronic lung diseases such as asthma and chronic obstructive pulmonary disease (COPD). We assessed the effects of cigarette smoke on barrier function and expression of multiple TJ and AJ proteins in the bronchial epithelium. We also examined whether treatment with glucocorticosteroids (GCSs), long-acting ß2-agonists (LABAs), and human cathelicidin LL-37 can protect against cigarette smoke extract (CSE)-induced barrier dysfunction. METHODS: Calu-3 cells cultured at the air-liquid interface were pretreated with or without GCSs, LABAs, GCSs plus LABAs, or LL-37, and subsequently exposed to CSE. Barrier function was assessed by transepithelial electronic resistance (TEER) measurements. Gene and protein expression levels of TJ and AJ proteins were analyzed by quantitative PCR and western blotting, respectively. Immunofluorescence staining of TJ and AJ proteins was performed. RESULTS: CSE decreased TEER and increased permeability in a concentration-dependent manner. CSE suppressed gene expression of claudin-1, claudin-3, claudin-4, claudin-7, claudin-15, occludin, E-cadherin, junctional adhesion molecule-A (JAM-A) and zonula occludens-1 (ZO-1) within 12 h post-CSE exposure, while suppressed protein expression levels of occludin at 12 h. CSE-treated cells exhibited discontinuous or attenuated immunostaining for claudin-1, claudin-3, claudin-4, occludin, ZO-1, and E-cadherin compared with untreated cells. GCS treatment partially restored CSE-induced TEER reduction, while LABA treatment had no effect. GCS and LABA combination treatment had no additive effect on CSE-induced TEER reduction and gene suppression of TJ and AJ proteins. Human cathelicidin LL-37 counteracted CSE-induced TEER reduction and prevented disruption of occludin and ZO-1. LL-37 also attenuated CSE-induced decreases in gene and protein expression levels of occludin. CONCLUSIONS: CSE caused airway epithelial barrier dysfunction and simultaneously downregulated multiple TJ and AJ proteins. GCS and LABA combination treatment had no additive effect on CSE-induced TEER reduction. LL-37 counteracted CSE-induced TEER reduction and prevented disruption of occludin and ZO-1. Use of LL-37 to counteract airway epithelial barrier dysfunction may have significant benefits for respiratory diseases such as asthma and COPD.
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Peptídeos Catiônicos Antimicrobianos/farmacologia , Brônquios/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Fumaça/efeitos adversos , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/efeitos dos fármacos , Produtos do Tabaco/efeitos adversos , Brônquios/metabolismo , Linhagem Celular , Impedância Elétrica , Células Epiteliais/metabolismo , Regulação da Expressão Gênica , Humanos , Permeabilidade , Transdução de Sinais , Proteínas de Junções Íntimas/genética , Junções Íntimas/genética , Junções Íntimas/metabolismo , CatelicidinasRESUMO
Double-stranded RNA derived from viruses induces host immune responses. PD-L1, also known as B7-H1, is an immune-checkpoint molecule associated with the escape of viruses from host immune systems, which plays a role in the persistence of viral infection, resulting in exacerbations of underlying diseases such as asthma and chronic obstructive pulmonary disease. Interleukin (IL)-22 is produced from various immune cells and has protective properties on mucosal tissue. The binding of IL-22 to IL-22 receptor induces STAT3 activation. We investigated the effect of IL-22 on the expression in airway epithelial cells in vitro and in mouse lungs in vivo after the stimulation with an analog of viral double-stranded RNA, polyinosinic-polycytidylic acid (poly I:C). Stimulation with poly I:C upregulated PD-L1 expression on BEAS-2B cells. This upregulation of PD-L1 was attenuated by IL-22 administration. STAT3 phosphorylation was induced by IL-22 and poly I:C. Treatment of cells with STAT3 siRNA abolished the effect of IL-22 on the poly I:C-induced upregulation of PD-L1. This upregulation of PD-L1 was also attenuated by IL-11, a cytokine inducing STAT3 phosphorylation, in BEAS-2B cells. In mouse lung cells in vivo, IL-22 suppressed poly I:C-induced upregulation of PD-L1. These results suggest that IL-22 attenuates virus-induced upregulation of PD-L1 in airway epithelial cells via a STAT3-dependent mechanism.
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Antígeno B7-H1/metabolismo , Interleucinas/metabolismo , RNA Viral/imunologia , Mucosa Respiratória/imunologia , Mucosa Respiratória/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Linhagem Celular , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Técnicas de Silenciamento de Genes , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Poli I-C/imunologia , Receptores de Interleucina/metabolismo , Mucosa Respiratória/virologia , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/genética , Regulação para Cima , Interleucina 22RESUMO
BACKGROUND: There has been no large-scale observational study examining the association between chronic obstructive pulmonary disease (COPD) or airflow limitation and carotid atherosclerosis in the general population across a wide range of generations in Asia. In the present study we assessed the association between airflow limitation and carotid intima-media thickness (IMT) in a general Japanese population, with consideration of a comprehensive array of cardiovascular risk factors.MethodsâandâResults:In all, 2,099 community-dwelling Japanese subjects were included in the study. Airflow limitation was defined by spirometry. Maximum and mean IMT values were measured using carotid ultrasonography. Among the subjects, 352 (16.8%) had airflow limitation. The geometric mean values of maximum IMT and mean IMT were significantly higher in subjects with than without airflow limitation (1.27 vs. 1.18 mm, respectively, for maximum IMT; 0.73 mm vs. 0.72 mm, respectively, for mean IMT) and increased with the severity of airflow limitation after adjustment for conventional risk factors, including smoking habits and serum high-sensitivity C-reactive protein. It should be noted that the magnitude of these associations was greater in the middle-aged (40-64 years) than elderly (≥65 years) subgroup. CONCLUSIONS: The findings of the present study suggest that airflow limitation is a significant risk factor for carotid atherosclerosis, especially in midlife, in the general Japanese population.
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Doenças das Artérias Carótidas/fisiopatologia , Espirometria , Adulto , Fatores Etários , Idoso , Povo Asiático , Espessura Intima-Media Carotídea , Humanos , Pessoa de Meia-Idade , Fatores de Risco , UltrassonografiaRESUMO
Spirometry in health checkup may contribute to early diagnosis of chronic obstructive pulmonary disease (COPD) and asthma. Although post-bronchodilator airflow limitation is essential for definite diagnosis of COPD and post-bronchodilator normalization of airflow is suggestive of asthma, this test has not been prevailed in health checkup. The objective of this study was to estimate the prevalence of airflow limitation defined by pre- and post-bronchodilator spirometry in health checkup. Post-bronchodilator spirometry was conducted for participants with airflow limitation in a town-wide health checkup for residents aged 40 years and older in Hisayama, a town in the western part of Japan. The prevalence of pre- and post-bronchodilator airway limitation defined by FEV1/FVC < 70% were estimated. A total of 2,232 participants underwent pre-bronchodilator spirometry. In males, the age of current smokers was significantly younger than those of never smokers and former smokers. In females, the ages of current- and former smokers were significantly younger than never smokers. The values of %FEV1 and %FVC in current smokers were significantly lower than those in former smokers and never smokers. Two hundred sixty nine subjects, 85% of total subjects with a pre-bronchodilator FEV1/FVC < 70%, completed post-bronchodilator spirometry. The prevalence of pre-bronchodilator airflow limitation was 14.6% in males and 13.7% in females, and the prevalence of post-bronchodilator airway limitation was 8.7% and 8.7%, respectively. Post-bronchodilator spirometry in health checkup would reduce the number of subjects with probable COPD to two-third. Recommendation for those examinees to take further evaluations may pave the way for early intervention.
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Broncodilatadores/farmacologia , Saúde , Ventilação Pulmonar/efeitos dos fármacos , Características de Residência , Idoso , Feminino , Volume Expiratório Forçado/efeitos dos fármacos , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Prevalência , EspirometriaRESUMO
IL-9 is a pleiotropic cytokine that can regulate autoimmune and allergic responses. Th9 cells can develop from naive T cells or Th2 cells through stimulation by TGF-ß in vitro. In this study, we demonstrated that Smad2 and Smad3 are necessary for IL-9 production from T cells in an OVA-induced asthma model using T cell-specific Smad2- and Smad3-deficient mice. Smad2 and Smad3 were also redundantly essential for TGF-ß signaling to induce histone modifications for Il9 transcription. Although Smad2/3 was recruited to the Il9 promoter by TGF-ß stimulation, they are not sufficient to activate the Il9 promoter. By the screening the transcription factors, we found that IFN regulatory factor 4 (IRF4) was essential for the Smad2/3-mediated Il9 promoter activation. In addition, Smad2/3 physically interacted with IRF4, and Smad2/3 did not bind to the Il9 promoter and could not induce Th9 in IRF4-deficient T cells. Similarly, IRF4 could not stimulate Il9 transcription in the absence of Smad2/3, and TGF-ß enhanced IRF4 recruitment to the Il9 promoter in a Smad2/3-dependent manner. We propose that Smad2/3 and IRF4 cooperatively transactivate the Il9 promoter and play an important role in regulating allergic immune responses by inducing Th9 cells.
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Fatores Reguladores de Interferon/imunologia , Interleucina-9/imunologia , Ativação Linfocitária/imunologia , Proteína Smad2/imunologia , Proteína Smad3/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Western Blotting , Imunoprecipitação da Cromatina , Modelos Animais de Doenças , Citometria de Fluxo , Hipersensibilidade/imunologia , Fatores Reguladores de Interferon/metabolismo , Interleucina-9/biossíntese , Interleucina-9/genética , Ativação Linfocitária/genética , Camundongos , Camundongos Knockout , Reação em Cadeia da Polimerase em Tempo Real , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Subpopulações de Linfócitos T/metabolismo , Ativação TranscricionalRESUMO
BACKGROUND: Chronic obstructive pulmonary disease (COPD) is highly prevalent worldwide. COPD is a treatable disease and it is important to identify COPD subjects, highlighting the need for an efficient screening measure. Although the COPD screening questionnaire (COPD Population Screener, COPD-PS) was developed as a screening tool, its validity is not clear in population-based studies. This study determines the validity of the COPD-PS in the general Japanese population. METHODS: All registered residents living in the town of Hisayama aged above 40 were solicited to participate in a health check-up in 2012. All subjects aged 40-79 without physician-diagnosed asthma or lung resection were recruited, and 2357 subjects with the COPD-PS recorded and valid spirometry measurements were analyzed. Persistent airflow obstruction (AO) was defined by post-bronchodilator FEV1/FVC < 0.7. The sensitivity and specificity of the COPD-PS score for identifying AO was assessed by logistic regression analysis. RESULTS: The prevalence of AO in this population was 6.5%. The overall area under the receiver operating characteristic (ROC) curve for the continuous COPD-PS score was 0.748. A cut-point of 4-points is recommended, resulting in a sensitivity of 67.1% and specificity of 72.9% with an area under the ROC curve of 0.70. The positive predictive value was 14.6% and negative predictive value was 97.0%. CONCLUSIONS: The COPD-PS appears to be an adequate measure for large scale screening of possible airflow obstruction requiring further testing with spirometry.
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Povo Asiático , Programas de Rastreamento , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Testes de Função Respiratória , Inquéritos e Questionários , Adulto , Idoso , Feminino , Volume Expiratório Forçado , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Razão de Chances , Vigilância da População , Prevalência , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Curva ROC , Valores de Referência , Reprodutibilidade dos Testes , Fatores de Risco , EspirometriaRESUMO
BACKGROUND: CD86-CD28 interaction has been suggested as the principal costimulatory pathway for the activation and differentiation of naïve T cells in allergic inflammation. However, it remains uncertain whether this pathway also has an essential role in the effector phase. We sought to determine the contribution of CD86 on dendritic cells in the reactivation of allergen-specific Th2 cells. METHODS: We investigated the effects of the downregulation of CD86 by short interfering RNAs (siRNAs) on Th2 cytokine production in the effector phase in vitro and on asthma phenotypes in ovalbumin (OVA)-sensitized and -challenged mice. RESULTS: Treatment of bone marrow-derived dendritic cells (BMDCs) with CD86 siRNA attenuated LPS-induced upregulation of CD86. CD86 siRNA treatment impaired BMDCs' ability to activate OVA-specific Th2 cells. Intratracheal administration of CD86 siRNA during OVA challenge downregulated CD86 expression in the airway mucosa. CD86 siRNA treatment ameliorated OVA-induced airway eosinophilia, airway hyperresponsiveness, and the elevations of OVA-specific IgE in the sera and IL-5, IL-13, and CCL17 in the bronchoalveolar lavage fluid, but not the goblet cell hyperplasia. CONCLUSION: These results suggest that local administration of CD86 siRNA during the effector phase ameliorates lines of asthma phenotypes. Targeting airway dendritic cells with siRNA suppresses airway inflammation and hyperresponsiveness in an experimental model of allergic asthma.
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Asma/prevenção & controle , Antígeno B7-2/metabolismo , Hiper-Reatividade Brônquica/prevenção & controle , Pulmão/metabolismo , Terapêutica com RNAi , Células Th2/metabolismo , Animais , Asma/genética , Asma/imunologia , Asma/metabolismo , Asma/fisiopatologia , Antígeno B7-2/genética , Hiper-Reatividade Brônquica/genética , Hiper-Reatividade Brônquica/imunologia , Hiper-Reatividade Brônquica/metabolismo , Hiper-Reatividade Brônquica/fisiopatologia , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/imunologia , Broncoconstrição , Células Cultivadas , Técnicas de Cocultura , Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Imunoglobulina E/sangue , Pulmão/imunologia , Pulmão/fisiopatologia , Ativação Linfocitária , Camundongos Endogâmicos BALB C , Ovalbumina , Fenótipo , Eosinofilia Pulmonar/genética , Eosinofilia Pulmonar/imunologia , Eosinofilia Pulmonar/metabolismo , Eosinofilia Pulmonar/prevenção & controle , Interferência de RNA , Células Th2/imunologia , TransfecçãoRESUMO
Efferocytosis, which is the homeostatic phagocytosis of apoptotic cells, prevents the release of toxic intracellular contents and subsequent tissue damage. Impairment of efferocytosis was reported in alveolar macrophages (AMs) of patients with chronic obstructive pulmonary disease (COPD), a common disease caused by smoking. In COPD, histone deacetylase (HDAC) activity is reduced in AMs. We investigated whether the reduction of HDAC activity is associated with the impairment of efferocytosis. Murine AMs were collected by bronchoalveolar lavage and their ability to efferocytose apoptotic human polymorphonuclear leukocytes was assessed. Pre-treatment of AMs with cigarette smoke extract (CSE) or trichostatin A (TSA), an HDAC inhibitor, suppressed efferocytosis and CSE reduced HDAC activity. TSA inhibited the activity of Rac, a key mediator of efferocytosis. These TSA-induced impairments were restored by treatment of AMs with aminophylline, a potent activator of HDAC. To further elucidate the underlying mechanism, we explored a role of CD9 in TSA-induced impairment of efferocytosis. CD9 is a transmembrane protein of the tetraspanin family that facilitates the uptake of several pathogens and other material. TSA profoundly down-regulated the expression of CD9 on AMs. The expression of CD9 was partly down-regulated by the Rac inhibitor. Pretreatment with an anti-CD9 mAb or CD9 small interfering RNA inhibited efferocytosis, which was attributable to the reduced binding of AMs to apoptotic cells. These results suggest that smoking impairs efferocytosis via inhibition of HDAC/Rac/CD9 pathways. Aminophylline/theophylline is effective in restoring the impairment of efferocytosis and might have benefit for the treatment of patients with COPD.
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Apoptose/imunologia , Histona Desacetilases/metabolismo , Macrófagos Alveolares/patologia , Neutrófilos/citologia , Fagocitose/imunologia , Fumar/efeitos adversos , Tetraspanina 29/antagonistas & inibidores , Proteínas rac de Ligação ao GTP/antagonistas & inibidores , Animais , Voluntários Saudáveis , Histona Desacetilases/imunologia , Humanos , Macrófagos Alveolares/enzimologia , Macrófagos Alveolares/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/enzimologia , Neutrófilos/imunologia , Fumar/imunologia , Tetraspanina 29/imunologia , Tetraspanina 29/metabolismo , Proteínas rac de Ligação ao GTP/imunologia , Proteínas rac de Ligação ao GTP/metabolismoRESUMO
Leukotriene B4 (LTB4) has been implicated in the pathogenesis of allergic diseases. BLT2, a low-affinity LTB4 receptor, is activated by LTB4 and 12(S)-hydroxyheptadeca-5Z,8E,10E-trienoic acid (12-HHT). Although the high-affinity LTB4 receptor BLT1 has been shown to exert proinflammatory roles, the role of BLT2 in allergic inflammation has not been clarified. To study the function of BLT2 in development of asthma, we used mice model of ovalbumin (OVA)-induced allergic airway disease. The 12-HHT levels were elevated in bronchoalveolar lavage (BAL) fluids of OVA-sensitized/challenged wild-type mice. BLT2-deficient mice exhibited enhanced eosinophilia in BAL fluids after OVA exposure. Interleukin (IL)-13 levels in BAL fluids and IL-13-producing CD4(+) T cells in the lungs were elevated in BLT2-deficient mice compared to wild-type mice, whereas the levels of IL-4, IL-5, and interferon (IFN)-γ in BAL fluids and serum OVA-specific IgE were comparable. Transfection of BLT2-specific small interfering RNA enhanced IL-13 production in CD4(+) T cells in vitro. Expression of BLT2 mRNA in CD4(+) T cells was significantly reduced in patients with asthma compared to healthy control subjects. These findings indicate that BLT2 has a protective role in allergic airway inflammation and that diminished BLT2 expression in CD4(+) T cells may contribute to the pathophysiology of asthma.
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Asma/imunologia , Eosinofilia/imunologia , Pulmão/imunologia , Receptores do Leucotrieno B4/imunologia , Adulto , Idoso , Animais , Asma/genética , Asma/metabolismo , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Células CHO , Cálcio/imunologia , Cálcio/metabolismo , Cricetinae , Cricetulus , Citocinas/imunologia , Citocinas/metabolismo , Eosinofilia/genética , Eosinofilia/metabolismo , Ácidos Graxos Insaturados/imunologia , Ácidos Graxos Insaturados/metabolismo , Humanos , Leucotrieno B4/imunologia , Leucotrieno B4/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Interferência de RNA , Receptores do Leucotrieno B4/deficiência , Receptores do Leucotrieno B4/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto JovemRESUMO
Pulmonary surfactant is essential for maintaining proper lung function. Alveolar epithelial type II (AE2) cells secrete surfactants via lamellar bodies (LBs). In tidal loading during each breath, the physiological cyclic stretching of AE2 cells promotes surfactant secretion. Excessive stretching inhibits surfactant secretion, which is considered to contribute to the development of lung damage. However, its precise mechanism remains unknown. This study tested whether actin polymerization and intracellular transport are required for pulmonary surfactant secretion and the association of actin polymerization and transport in identical human AE2-derived A549 cells using live-cell imaging, not in the bulk cells population. We found that overstretching approximately doubled actin polymerization into filaments (F-actin) and suppressed LB secretion by half in the fluorescent area ratio, compared with physiological stretching (F-actin: 1.495 vs 0.643 (P < 0.01); LB: 0.739 vs 0.332 (P < 0.01)). An inhibitor of actin polymerization increased LB secretion. Intracellular tracking using fluorescent particles revealed that cyclic stretching shifted the particle motion perpendicularly to the direction of stretching according to the orientation of the F-actin (proportion of perpendicular axis motion prior particle: 0h 40.12 % vs 2h 63.13 % (P < 0.01)), and particle motion was restricted over time in the cells subjected to overstretching, indicating that overstretching regulates intracellular transport dynamics (proportion of stop motion particle: 0h 1.01 % vs 2h 11.04 % (P < 0.01)). These findings suggest that overstretching changes secretion through the cytoskeleton: overstretching AE2 cells inhibits pulmonary surfactant secretion, at least through accelerating actin polymerization and decreasing intracellular trafficking, and the change in actin orientation would modulate intracellular trafficking.
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Airway viral infection disturbs the health-related quality of life. B7-H1 (also known as PD-L1) is a coinhibitory molecule associated with the escape of viruses from the mucosal immunity, leading to persistent infection. Most respiratory viruses generate double-stranded (ds) RNA during replication. The stimulation of cultured airway epithelial cells with an analog of viral dsRNA, polyinosinic-polycytidylic acid (poly IC) upregulates the expression of B7-H1 via activation of the nuclear factor κB(NF-κB). The mechanism of upregulation was investigated in association with phosphatidylinositol 3-kinases (PI3Ks). Poly IC-induced upregulation of B7-H1 was profoundly suppressed by a pan-PI3K inhibitor and partially by an inhibitor or a small interfering (si)RNA for PI3Kδ in BEAS-2B cells. Similar results were observed in the respiratory syncytial virus-infected cells. The expression of p110δ was detected by Western blot and suppressed by pretreatment with PI3Kδ siRNA. The activation of PI3Kδ is typically induced by oxidative stress. The generation of reactive oxygen species was increased by poly IC. Poly IC-induced upregulation of B7-H1 was attenuated by N-acetyl-L-cysteine, an antioxidant, or by oxypurinol, an inhibitor of xanthine oxidase. Poly IC-induced activation of NF-κB was suppressed by a pan-PI3K inhibitor but not by a PI3Kδ inhibitor. These results suggest that PI3Kδ mediates dsRNA-induced upregulation of B7-H1 without affecting the activation of NF-κB.
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Antígeno B7-H1/biossíntese , DNA Viral/metabolismo , Células Epiteliais/citologia , Células Epiteliais/metabolismo , RNA de Cadeia Dupla/metabolismo , Mucosa Respiratória/citologia , Mucosa Respiratória/metabolismo , Linhagem Celular , DNA Viral/administração & dosagem , DNA Viral/genética , Humanos , RNA de Cadeia Dupla/administração & dosagem , RNA de Cadeia Dupla/genética , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genéticaRESUMO
BACKGROUND: Clinical studies showed the contribution of viral infection to the development of asthma. Although mast cells have multiple roles in the pathogenesis of allergic asthma, their role of in the virus-associated pathogenesis of asthma remains unknown. Most respiratory viruses generate double-stranded (ds) RNA during their replication. dsRNA provokes innate immune responses. We recently showed that an administration of polyinocinic polycytidilic acid (poly IC), a mimetic of viral dsRNA, during allergen sensitization augments airway eosinophilia and hyperresponsiveness in mice via enhanced production of IL-13. METHODS: The effect of poly IC on allergen-induced airway eosinophilia was investigated for mast cell-conserved Kit+/+ mice and -deficient KitW/KitW-v mice. The outcome of mast cell reconstitution was further investigated. RESULTS: Airway eosinophilia and IL-13 production were augmented by poly IC in Kit+/+ mice but not in KitW/KitW-v mice. When KitW/KitW-v mice were reconstituted with bone marrow-derived mast cells (BMMCs), the augmentation was restored. The augmentation was not induced in the mice systemically deficient for TIR domain-containing adaptor-inducing IFN-ß (TRIF) or interferon regulatory factor (IRF)-3, both mediate dsRNA-triggered innate immune responses. The augmentation was, however, restored in KitW/KitW-v mice reconstituted with TRIF-deficient or IRF-3-deficient BMMCs. Although leukotriene B4 and prostaglandin D2 are major lipid mediators released from activated mast cells, no their contribution was shown to the dsRNA-induced augmentation of airway eosinophilia. CONCLUSIONS: We conclude that mast cells contribute to dsRNA-induced augmentation of allergic airway inflammation without requiring direct activation of mast cells with dsRNA or involvement of leukotriene B4 or prostaglandin D2.
Assuntos
Asma/patologia , Hiper-Reatividade Brônquica/patologia , Modelos Animais de Doenças , Eosinofilia/patologia , Mastócitos/patologia , RNA de Cadeia Dupla/genética , Animais , Asma/induzido quimicamente , Asma/genética , Hiper-Reatividade Brônquica/induzido quimicamente , Hiper-Reatividade Brônquica/genética , Células Cultivadas , Eosinofilia/genética , Eosinofilia/imunologia , Mastócitos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Poli I-C/toxicidadeRESUMO
The effects of tiotropium, an inhaled long-acting anti-cholinergic agent, on lung function were investigated in obstructed severe asthmatics with and without emphysematous changes despite maximal recommended treatments with high-dose of inhaled glucocorticoids and inhaled long-acting ß(2)-agonists. We conducted a double-blind, placebo-controlled study of an inhaled single-dose of tiotropium in 18 asthmatics with emphysema and 18 without emphysema in a crossover manner. The primary efficacy outcome was the relative change in forced expiratory volume in 1 s (FEV(1)) from baseline to 60 min, and the secondary outcome was a relative change in FEV(1) from baseline to 12 h. Subsequently, the patients were treated with tiotropium inhaled once daily for 12 weeks in an open label manner, and lung function and symptoms were evaluated. At baseline, patients with or without emphysema had a mean FEV(1) of 55.9% before tiotropium and 56.8% before placebo, or 77.4% before tiotropium and 77.6% before placebo of the predicted value and were taking a mean dose of inhaled glucocorticoids of 1444 or 1422 µg/day. Among patients with emphysema, the increase from baseline FEV(1) was 12.6 percentage points higher at 60 min after tiotropium than after placebo. Among patients without emphysema, the increase from baseline FEV(1) was 5.4 percentage points higher at 60 min after tiotropium than after placebo. Tiotropium resulted in improved lung function and symptoms in asthmatics with and without emphysema. These findings suggest that tiotropium will provide a new strategy for the treatment of bronchial asthma and of overlapping asthma and COPD.
Assuntos
Asma/tratamento farmacológico , Broncodilatadores/uso terapêutico , Volume Expiratório Forçado/efeitos dos fármacos , Derivados da Escopolamina/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Asma/fisiopatologia , Estudos Cross-Over , Método Duplo-Cego , Enfisema , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Derivados da Escopolamina/farmacologia , Brometo de Tiotrópio , Capacidade Vital/efeitos dos fármacosRESUMO
Activation of innate immunity against viruses in the respiratory tracts affects the development of asthma. Most respiratory viruses generate double-stranded (ds)RNA during their replication. We recently showed that a low-dose administration of polyinosinic polycytidylic acid (poly IC), a mimetic of viral dsRNA, during allergen sensitization augments airway eosinophilia and hyperresponsiveness in mice via enhanced production of IL-13 from T cells. However, a phenotype of asthma under severer load of dsRNA remains unknown. d-galactosamine (d-GalN) is known as a strong sensitizer of poly IC. Mice were treated with poly IC plus d-GalN during allergen sensitization. A sublethal dose of poly IC/d-GalN augmented airway eosinophilia and CD4(+) T-cell accumulation in the lungs but not airway hyperresponsiveness. The augmented inflammation was associated with decreased IL-10 in the bronchoalveolar lavage fluid and decreased Foxp3(+) regulatory T cells in the lungs. Serum IL-6 was prominently higher in the mice treated with poly IC/d-GalN than in that with poly IC alone or d-GalN alone. Poly IC/d-GalN did not affect IL-17-producing T cells in the lungs. Poly IC/d-GalN failed to augment airway eosinophilia after anti-IL-10 receptor monoclonal antibody treatment during allergen challenge. Finally, anti-IL-6 receptor monoclonal antibody treatment before poly IC/d-GalN completely prevented the decrease of IL-10 and Foxp3(+) regulatory T cells and the augmentation of airway inflammation. These results indicate that enhanced production of IL-6 by poly IC/d-GalN induces the augmentation of allergic inflammation via suppression of Foxp3(+) regulatory T-cell/IL-10 axis. IL-6 may be a target for preventing asthma augmentation related to severe virus infection.
Assuntos
Fatores de Transcrição Forkhead/imunologia , Hipersensibilidade/imunologia , Inflamação/imunologia , Interleucina-10/imunologia , Interleucina-6/biossíntese , RNA de Cadeia Dupla/fisiologia , Linfócitos T/imunologia , Animais , Asma/imunologia , Citometria de Fluxo , CamundongosRESUMO
Suppressor of cytokine signaling (SOCS)3 is a major negative feedback regulator of signal transducer and activator of transcription (STAT)3-activating cytokines. Transgenic mouse studies indicate that high levels of SOCS3 in T cells result in type 2 T helper cell (Th2) skewing and lead to hypersensitivity to allergic diseases. To define the physiological roles of SOCS3 in T cells, we generated T cell-specific SOCS3 conditional knockout mice. We found that the mice lacking SOCS3 in T cells showed reduced immune responses not only to ovalbumin-induced airway hyperresponsiveness but also to Leishmania major infection. In vitro, SOCS3-deficient CD4+ T cells produced more transforming growth factor (TGF)-beta1 and interleukin (IL)-10, but less IL-4 than control T cells, suggesting preferential Th3-like differentiation. We found that STAT3 positively regulates TGF-beta1 promoter activity depending on the potential STAT3 binding sites. Furthermore, chromatin immunoprecipitation assay revealed that more STAT3 was recruited to the TGF-beta1 promoter in SOCS3-deficient T cells than in control T cells. The activated STAT3 enhanced TGF-beta1 and IL-10 expression in T cells, whereas the dominant-negative form of STAT3 suppressed these. From these findings, we propose that SOCS3 regulates the production of the immunoregulatory cytokines TGF-beta1 and IL-10 through modulating STAT3 activation.
Assuntos
Regulação para Baixo/imunologia , Interleucina-10/biossíntese , Proteínas Supressoras da Sinalização de Citocina/deficiência , Proteínas Supressoras da Sinalização de Citocina/genética , Linfócitos T Auxiliares-Indutores/metabolismo , Fator de Crescimento Transformador beta/biossíntese , Animais , Diferenciação Celular/imunologia , Leishmania major/imunologia , Leishmaniose Cutânea/genética , Leishmaniose Cutânea/imunologia , Leishmaniose Cutânea/metabolismo , Camundongos , Camundongos Knockout , Regiões Promotoras Genéticas , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/fisiologia , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina/fisiologia , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Auxiliares-Indutores/imunologia , Células Th2/imunologia , Células Th2/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta1 , Regulação para Cima/genética , Regulação para Cima/imunologiaRESUMO
CD4(+) T cells, particularly T helper (Th) 2 cells, play a pivotal role in the pathophysiology of allergic asthma. Suppressor of cytokine signaling (SOCS) proteins control the balance of CD4(+) T cell differentiation. Mice that lack SOCS3 in T cells by crossing SOCS3-floxed mice with Lck-Cre-transgenic mice have reduced allergen-induced eosinophilia in the airways. Here, we studied the effects of SOCS3 silencing with small interfering (si) RNA in primary CD4(+) T cells on Th2 cell differentiation and on asthmatic responses in mice. Th2 cells were generated from ovalbumin (OVA)-specific T cell receptor-transgenic mice in vitro and transferred into recipient mice. Transfection of SOCS3-specific siRNA attenuated Th2 response in vitro. Adoptive transfer of SOCS3-siRNA T cells exhibited markedly suppressed airway hyperresponsiveness and eosinophilia after OVA challenge, with a concomitant decrease in OVA-specific CD4(+) T cell accumulation in the airways. To investigate the mechanism of this impaired CD4(+) T cell accumulation, we inactivated SOCS3 of T cells by crossing SOCS3-floxed (SOCS3(flox/flox)) mice with CD4-Cre transgenic mice. CD4-Cre × SOCS3(flox/flox) mice exhibited fewer IL-4-producing cells and more reduced eosinophil infiltration in bronchoalveolar lavage fluids than control mice in a model of OVA-induced asthma. Expression of CCR3 and CCR4 in CD4(+) T cells was decreased in CD4-Cre × SOCS3(flox/flox) mice. CCR4 expression was also decreased in CD4(+) T cells after transfer of SOCS3 siRNA-treated T cells. These findings suggest that the therapeutic modulation of SOCS3 expression in CD4(+) T cells might be effective in preventing the development of allergic asthma.
Assuntos
Asma/imunologia , Asma/fisiopatologia , Hiper-Reatividade Brônquica/imunologia , Linfócitos T CD4-Positivos/metabolismo , RNA Interferente Pequeno/metabolismo , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Transferência Adotiva , Animais , Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular , Modelos Animais de Doenças , Regulação para Baixo , Heterozigoto , Depleção Linfocítica , Camundongos , Receptores CCR3/metabolismo , Receptores CCR4/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas , Células Th2/citologia , Células Th2/imunologiaRESUMO
Clinical and epidemiological studies have shown the contribution of viral infection to the development of allergic asthma. Many RNA viruses, pathogenic for the respiratory tract, generate double-stranded (ds)RNA during their replication. Typical innate immune responses triggered by dsRNA involve the endosomal and cytoplasmic pathways. The former is mediated by Toll/IL-1R domain-containing adaptor inducing IFN-ß (TRIF), and the latter by IFN-ß promoter stimulator 1 (IPS-1). We explored the effect of polyinocinic polycytidilic acid, a synthetic dsRNA, on the development of an asthma phenotype in mice. Administration of dsRNA during ovalbumin sensitization augmented airway eosinophilia and airway hyperresponsiveness after an antigen challenge, which was associated with enhanced induction of IL-13-producing CD8(+) T cells. The augmentation was induced in IPS-1-deficient mice but not in TRIF-deficient mice. The interactions between dendritic cells (DCs) and T cells are regulated by B7-family costimulatory molecules, including B7-H1 (also known as PD-L1), a putative ligand for programmed death-1 (PD-1). Treatment of bone marrow-derived DCs with dsRNA enhanced B7-H1 expression in a TRIF-dependent manner. Additionally, dsRNA increased B7-H1 expression on DCs in the draining lymph nodes of ovalbumin-sensitized mice. The augmentation of the asthma phenotype was prevented by the treatment of mice with anti-B7-H1 mAb but not with anti-PD-1 mAb. The augmentation was not induced in B7-H1-deficient mice. These results suggest that dsRNA-triggered activation of the innate immune system in sensitization leads to augmentation of the asthma phenotype via IL-13 mainly from CD8(+) T cells. B7-H1 plays a crucial role in the process without requiring interaction with PD-1.
Assuntos
Asma/induzido quimicamente , Asma/imunologia , Antígeno B7-1/imunologia , Imunidade Inata/efeitos dos fármacos , Imunidade Inata/imunologia , Glicoproteínas de Membrana/imunologia , Peptídeos/imunologia , RNA de Cadeia Dupla/efeitos adversos , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/genética , Proteínas Adaptadoras de Transporte Vesicular/imunologia , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Asma/genética , Asma/metabolismo , Asma/patologia , Antígeno B7-1/biossíntese , Antígeno B7-1/genética , Antígeno B7-H1 , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Células Dendríticas/patologia , Interleucina-13/biossíntese , Interleucina-13/genética , Interleucina-13/imunologia , Glicoproteínas de Membrana/biossíntese , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Knockout , Ovalbumina/efeitos adversos , Ovalbumina/farmacologia , Peptídeos/genética , Fenótipo , Eosinofilia Pulmonar/induzido quimicamente , Eosinofilia Pulmonar/genética , Eosinofilia Pulmonar/imunologia , Eosinofilia Pulmonar/patologia , RNA de Cadeia Dupla/farmacologiaRESUMO
Neuromedin U (NMU) is a neuropeptide that is expressed in the gastrointestinal tract and central nervous system. NMU interacts with two G protein-coupled receptors, NMU-R1 and NMU-R2. Whereas NMU-R2 localizes predominantly to nerve cells, NMU-R1 is expressed in peripheral tissues including lymphocytes and monocytes, suggesting a role of NMU in immunoregulation. However, the functions of NMU in peripheral tissues have not been clarified. In this study, using NMU-deficient mice, we first demonstrated that NMU plays an important role in mast cell-mediated inflammation. Complete Freund's adjuvant-induced mast cell degranulation as well as edema and neutrophil infiltration, which occurred weakly in mast cell-deficient WBB6F(1)-W/W(v) mice, did not occur in NMU-deficient mice. Moreover, intraplantar injection of NMU into paws induced early inflammatory responses such as mast cell degranulation, vasodilation, and plasma extravasation in WT mice but not in WBB6F(1)-W/W(v) mice. NMU-R1 was highly expressed in primary mast cells, and NMU induced Ca(2+) mobilization and degranulation in peritoneal mast cells. These data indicate that NMU promotes mast cell-mediated inflammation; therefore, NMU receptor antagonists could be a novel target for pharmacological inhibition of mast cell-mediated inflammatory diseases.