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BACKGROUND: Injectable daxibotulinumtoxinA (an investigational botulinum toxin, RT002) may offer a more prolonged duration of response-and therefore less frequent dosing-than onabotulinumtoxinA. OBJECTIVES: To perform a phase 2, open-label, dose-escalation study to assess the efficacy and safety of daxibotulinumtoxinA in cervical dystonia. METHODS: Subjects with moderate-to-severe isolated cervical dystonia were enrolled in sequential cohorts to receive a single open-label, intramuscular dose of injectable daxibotulinumtoxinA of up to 200 U (n = 12), 200-300 U (n = 12), or 300-450 U (n = 13; https://clinicaltrials.gov identifier NCT02706795). RESULTS: Overall, 33/37 enrollees completed the trial. DaxibotulinumtoxinA was associated with mean reductions in Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS)-Total score of 16.8 (38%) at week 4, 21.3 (50%) at week 6, and 12.8 (30%) at week 24. The proportion of subjects who were responders (achieved ≥ 20% reduction in TWSTRS-Total score) was 94% at week 6 and 68% at week 24. The median duration of response (time until > 20% of the improvement in TWSTRS-Total score achieved at week 4 was no longer retained or re-treatment was needed) was 25.3 weeks (95% CI, 20.14-26.14 weeks). There were no serious adverse events and there was no apparent dose-related increase in the incidence of adverse events. The most common treatment-related adverse events were dysphagia (14%) and injection site erythema (8%). CONCLUSIONS: Preliminary assessments suggest that injectable daxibotulinumtoxinA at doses up to 450 U is well tolerated and may offer prolonged efficacy in the treatment of cervical dystonia. Further studies involving larger numbers of patients are now warranted.
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OBJECTIVES: We wished to evaluate the effects of an antigranulocyte-macrophage colony-stimulating factor monoclonal antibody (KB003) on forced expiratory volume in 1 s (FEV1), asthma control and asthma exacerbations in adult asthmatics inadequately controlled by long-acting bronchodilators and inhaled/oral corticosteroids. SETTINGS: 47 ambulatory asthma care centres globally. PRIMARY OUTCOME MEASURES: Change in FEV1 at week 24. PARTICIPANTS: 311 were screened, 160 were randomised and 129 completed the study. INTERVENTIONS: 7 intravenous infusions of either 400 mg KB003 or placebo at baseline and weeks 2, 4, 8, 12, 16 and 20. PRIMARY AND SECONDARY OUTCOME MEASURES: FEV1 at week 24, asthma control, exacerbation rates and safety in all participants as well as prespecified subgroups. MAIN RESULTS: In the KB003 treated group, FEV1 at week 24 improved to 118 mL compared with 54 mL in the placebo group (p=0.224). However, FEV1 improved to 253 vs 26 mL at week 24 (p=0.02) in eosinophilic asthmatics (defined as >300 peripheral blood eosinophils/mL at baseline) and comparable improvements were seen at weeks 20 (p=0.034) and 24 (p=0.077) in patients with FEV1 reversibility ≥ 20% at baseline and at weeks 4 (p=0.029), 16 (p=0.018) and 20 (p=0.006) in patients with prebronchodilator FEV1 ≤ 50% predicted at baseline. There were no effects on asthma control or exacerbation rates. The most frequent adverse events in the KB003 group were rhinosinusitis and headache. There was no significant difference in antidrug antibody response between placebo and treated groups. There were no excess infections or changes in biomarkers known to be associated with the development of pulmonary alveolar proteinosis. CONCLUSIONS: Higher doses and/or further asthma phenotyping may be required in future studies with KB003. TRIAL REGISTRATION NUMBER: NCT01603277; Results.
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Antiasmáticos/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Asma/tratamento farmacológico , Volume Expiratório Forçado , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Corticosteroides/uso terapêutico , Adulto , Antiasmáticos/efeitos adversos , Antiasmáticos/farmacologia , Asma/imunologia , Asma/fisiopatologia , Broncodilatadores/uso terapêutico , Eosinófilos/metabolismo , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , FenótipoRESUMO
BACKGROUND: Preclinical studies suggest that interleukin-9 may be a central mediator in the development and maintenance of airway inflammation in asthma. The aim of this study was therefore to evaluate the effects of MEDI-528, an anti-interleukin-9 monoclonal antibody, in adults with confirmed uncontrolled moderate-to-severe asthma. METHODS: In this prospective double-blind, multicenter, parallel-group study, 329 subjects were randomized (1:1:1:1) to subcutaneous placebo or MEDI-528 (30, 100, 300 mg) every 2 weeks for 24 weeks, in addition to their usual asthma medications. The primary endpoint was change in mean Asthma Control Questionnaire-6 (ACQ-6) score at week 13. Secondary endpoints included weighted asthma exacerbation rates and pre-bronchodilator forced expiratory volume in 1 second (FEV1) at weeks 13 and 25, as well as Asthma Quality of Life Questionnaire scores at weeks 12 and 25 and the safety of MEDI-528 throughout the study period. The primary endpoint was analyzed using analysis of covariance. RESULTS: The study population (n = 327) was predominantly female (69%) with a mean age of 43 years (range 18-65). The mean (SD) baseline ACQ-6 score for placebo (n = 82) and combined MEDI-528 (n = 245) was 2.8 (0.7) and 2.8 (0.8); FEV1 % predicted was 70.7% (15.9) and 71.5% (16.7). Mean (SD) change from baseline to week 13 in ACQ-6 scores for placebo vs combined MEDI-528 groups was -1.2 (1.0) vs -1.2 (1.1) (p = 0.86). Asthma exacerbation rates (95% CI) at week 25 for placebo vs MEDI-528 were 0.58 (0.36-0.88) vs 0.49 (0.37-0.64) exacerbations/subject/year (p = 0.52). No significant improvements in FEV1 % predicted were observed between the placebo and MEDI-528 groups. Adverse events were comparable for placebo (82.9%) and MEDI-528 groups (30 mg, 76.5%; 100 mg, 81.9%; 300 mg, 85.2%). The most frequent were asthma (placebo vs MEDI-528, 30.5% vs 33.5%), upper respiratory tract infection (14.6% vs 17.1%), and headache (9.8% vs 9.8%). CONCLUSIONS: The addition of MEDI-528 to existing asthma controller medications was not associated with any improvement in ACQ-6 scores, asthma exacerbation rates, or FEV1 values, nor was it associated with any major safety concerns. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00968669.
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Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Asma/tratamento farmacológico , Asma/fisiopatologia , Interleucina-9/imunologia , Adolescente , Adulto , Idoso , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/farmacologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Volume Expiratório Forçado/efeitos dos fármacos , Volume Expiratório Forçado/fisiologia , Humanos , Injeções Subcutâneas , Interleucina-9/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Qualidade de Vida , Inquéritos e Questionários , Resultado do Tratamento , Adulto JovemRESUMO
Idiopathic pulmonary fibrosis (IPF) is a disease of unknown etiology with considerable morbidity and mortality. Cigarette smoking is one of the most recognized risk factors for development of IPF. Furthermore, recent work suggests that smoking may have a detrimental effect on survival of patients with IPF. The mechanism by which smoking may contribute to the pathogenesis of IPF is largely unknown. However, accumulating evidence suggests that increased oxidative stress might promote disease progression in IPF patients who are current and former smokers. In this review, potential mechanisms by which cigarette smoking affects IPF, the effects of cigarette smoking on accelerated loss of lung function in patients with IPF, key genetic studies evaluating the potential candidate genes and gene-environment (smoking) interaction, diagnosis, and treatment with emphasis on recently closed and ongoing clinical trials are presented.
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Asthma is a complex disease characterized by variable airflow limitation, hyperresponsiveness, and airways inflammation. Despite valuable therapeutic advances to control asthma symptoms in the last decade, a quantifiable proportion of patients with moderate to severe asthma continue to experience inadequate disease control, highlighting an important unmet need. In animal models of asthma, interleukin (IL)-9 regulates the development of airway inflammation, mucus production, airway hyperresponsiveness, and airway fibrosis largely by increasing mast cell numbers and activity in the airways. Mast cells are involved in the pathogenesis of eosinophilic and noneosinophilic asthma. Thus, targeting the IL-9 pathway may provide a new therapeutic modality for asthma. The purpose of this review is to summarize the IL-9-mast cell axis in the pathogenesis of asthma and discuss clinical studies with a humanized anti-IL-9 monoclonal antibody, MEDI-528, in subjects with asthma.
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Asma/imunologia , Asma/terapia , Imunoterapia , Interleucina-9/imunologia , Mastócitos/imunologia , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Asma/fisiopatologia , Ensaios Clínicos como Assunto , Modelos Animais de Doenças , Humanos , Interleucina-9/antagonistas & inibidores , Equilíbrio Th1-Th2/efeitos dos fármacosRESUMO
BACKGROUND: Interleukin-9 (IL-9)-targeted therapies may offer a novel approach for treating asthmatics. Two randomized placebo-controlled studies were conducted to assess the safety profile and potential efficacy of multiple subcutaneous doses of MEDI-528, a humanized anti-IL-9 monoclonal antibody, in asthmatics. METHODS: Study 1: adults (18-65 years) with mild asthma received MEDI-528 (0.3, 1, 3 mg/kg) or placebo subcutaneously twice weekly for 4 weeks. Study 2: adults (18-50 years) with stable, mild to moderate asthma and exercise-induced bronchoconstriction received 50 mg MEDI-528 or placebo subcutaneously twice weekly for 4 weeks. Adverse events (AEs), pharmacokinetics (PK), immunogenicity, asthma control (including asthma exacerbations), and exercise challenge test were evaluated in study 1, study 2, or both. RESULTS: In study 1 (N = 36), MEDI-528 showed linear serum PK; no anti-MEDI-528 antibodies were detected. Asthma control: 1/27 MEDI-528-treated subjects had 1 asthma exacerbation, and 2/9 placebo-treated subjects had a total of 4 asthma exacerbations (one considered a serious AE). In study 2, MEDI-528 (n = 7) elicited a trend in the reduction in mean maximum decrease in FEV1 post-exercise compared to placebo (n = 2) (-6.49% MEDI-528 vs -12.60% placebo; -1.40% vs -20.10%; -5.04% vs -15.20% at study days 28, 56, and 150, respectively). Study 2 was halted prematurely due to a serious AE in an asymptomatic MEDI-528-treated subject who had an abnormal brain magnetic resonance imaging that was found to be an artifact on further evaluation. CONCLUSIONS: In these studies, MEDI-528 showed an acceptable safety profile and findings suggestive of clinical activity that support continued study in subjects with mild to moderate asthma.
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Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/uso terapêutico , Asma/tratamento farmacológico , Interleucina-9/imunologia , Adolescente , Adulto , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados , Asma/fisiopatologia , Asma Induzida por Exercício/tratamento farmacológico , Asma Induzida por Exercício/fisiopatologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Injeções Subcutâneas , Interleucina-9/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Testes de Função Respiratória , Resultado do Tratamento , Adulto JovemRESUMO
AIM: To assess the bioavailability and pharmacokinetics of CAT-354, an anti-IL-13 human monoclonal IgG4 antibody, following subcutaneous (s.c.) and intravenous (i.v.) administration. METHODS: This was a single-dose, randomized, open-label, parallel-group bioavailability study. Healthy male subjects aged 20-54 years were randomly assigned to one of three dose groups (n= 10/group) to receive CAT-354: 150 mg i.v.; 150 mg s.c. or 300 mg s.c. (two 150 mg injections). Serum pharmacokinetics, adverse events (AEs), vital signs, electrocardiograms and laboratory parameters were assessed. RESULTS: CAT-354 showed bioavailability of 62% and 60% after 150 mg and 300 mg s.c. doses, respectively, and linear pharmacokinetics over the dose range tested. Peak serum concentrations in the s.c. groups occurred after 3-9 (median 5) days, with a mean elimination half-life of 19.2 +/- 3.1 days (150 mg) and 19.4 +/- 3.59 days (300 mg) after s.c. and 21.4 +/- 2.46 days after i.v. administration. Volume of distribution at steady state (V(ss)) was 4960 +/- 1440 ml kg(-1) after i.v. (slightly greater than plasma volume). Average apparent clearances (CL/F) were 292 +/- 82.3 and 307 +/- 109 ml day(-1) after 150 and 300 mg s.c., respectively; systemic CL of 188 +/- 84.0 ml day(-1) after i.v. dosing was consistent with endogenous IgG and reticuloendothelial elimination. No severe or serious AEs occurred. Among 40 reported AEs, 25 were headache, sinus disorders/respiratory symptoms and changes in body temperature perception. CONCLUSIONS: CAT-354 exhibited bioavailability of approximately 60% when given s.c. to healthy male subjects.
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Anticorpos Monoclonais/farmacocinética , Adulto , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/imunologia , Área Sob a Curva , Disponibilidade Biológica , Relação Dose-Resposta a Droga , Eletrocardiografia , Meia-Vida , Humanos , Injeções Intravenosas , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: Plasminogen activator inhibitor (PAI)-1 is a key regulator of the fibrinolytic system. PAI-1 levels are markedly elevated in the asthmatic airways. The 4G/5G polymorphism of the PAI-1 gene is associated with allergic asthma. OBJECTIVE: To characterize the mechanisms of the 4G/5G-dependent PAI-1 expression in mast cells (MCs), a major source of PAI-1 and key effector cells in asthma. METHODS: Transcription of PAI-1 was assessed by transiently transfecting human MC line (HMC-1) cells with the luciferase-tagged PAI-1 promoters containing the 4G or 5G allele (4G-PAI-1 or 5G-PAI-1 promoter). Upstream stimulatory factor (USF)-1 and the E-box interactions were studied by electrophoretic mobility shift assays and supershift assays. Expression of USF-1 was determined by Western blot analysis. RESULTS: The 4G-PAI-1 promoter has higher promoter activity than the 5G-PAI-1 promoter in stimulated HMC-1 cells, and the E-box adjacent to the 4G/5G site (E-4G/5G) regulates the genotype-specific PAI-1 transcription. USF-1 binds to the E-4G with greater affinity than to the E-5G. USF-1 level is increased in HMC-1 cells after stimulation, and elevated USF-1 enhances PAI-1 transcription. Overexpression of wild-type USF-1 or dominant-negative USF remedies the 4G/5G-dependent PAI-1 transcription. CONCLUSION: Binding of USF-1 to the E-4G/5G regulates the 4G/5G polymorphism-dependent PAI-1 expression in MCs.
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Alelos , Elementos E-Box/fisiologia , Nucleotídeos de Guanina/genética , Mastócitos/metabolismo , Inibidor 1 de Ativador de Plasminogênio/biossíntese , Inibidor 1 de Ativador de Plasminogênio/genética , Polimorfismo Genético/fisiologia , Fatores Estimuladores Upstream/metabolismo , Asma/genética , Asma/metabolismo , Asma/patologia , Linhagem Celular , Elementos E-Box/genética , Nucleotídeos de Guanina/metabolismo , Humanos , Mastócitos/imunologia , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Ligação Proteica/genética , Regulação para Cima/genética , Fatores Estimuladores Upstream/biossíntese , Fatores Estimuladores Upstream/genéticaRESUMO
Plasminogen activator inhibitor (PAI)-1 promotes development of asthma. PAI-1 mRNA and protein are markedly induced in activated mast cells (MCs), a major effector cell type in asthma. However, regulatory mechanisms of PAI-1 transcription in MCs are unknown. We present first evidence that PAI-1 is transcriptionally regulated in human MCs (hMCs). In addition to three enhancer regions, we demonstrated that the E-box at -566 bp to -561 bp is the negative regulatory element, and the specific and constitutive binding of the upstream stimulating factor-1 to this E-box is the key mechanism of the negative regulation of PAI-1 expression in hMCs.
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Elementos E-Box/genética , Mastócitos/metabolismo , Inibidor 1 de Ativador de Plasminogênio/genética , Fatores Estimuladores Upstream/genética , Linhagem Celular , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Ionomicina/farmacologia , Luciferases/genética , Luciferases/metabolismo , Mastócitos/citologia , Mastócitos/efeitos dos fármacos , Mutagênese Sítio-Dirigida , Fosforilação , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Transcrição Gênica/efeitos dos fármacos , Transfecção , Fatores Estimuladores Upstream/metabolismoRESUMO
Keloids represent a prolonged inflammatory fibrotic state with areas that display distinctive histological features characterized by an abundant extracellular matrix stroma, a local infiltration of inflammatory cells including mast cells, and a milieu of enriched cytokines. Previous studies from our laboratory demonstrated an intrinsic higher level of HIF-1alpha and VEGF protein expression in keloid tissues compared with their adjacent unremarkable skins. To further investigate the mechanisms underlying the elevated expression of HIF-1alpha and VEGF in keloids, we exposed a co-culture of keloid fibroblasts and mast cells (HMC-1) to hypoxic conditions and studied the expression of HIF-1alpha and its target gene, VEGF. Our results showed that hypoxia-dependent HIF-1alpha protein accumulation and VEGF expression is augmented in keloid fibroblasts when co-cultured with HMC-1 cells under the condition where direct cell-cell contact is allowed. But such augmentation is not observed in the transwell co-culture system whereas fibroblasts and HMC-1 cells were separated by a porous membrane. Our results also indicated that the enhancement of hypoxia-mediated activation of ERK1/2 and Akt requires direct cell-cell interaction between mast cells and keloid fibroblasts, and activation of both ERK1/2 and Akt is involved in the hypoxia-dependent HIF-1alpha protein accumulation and VEGF expression in the co-culture system. These findings suggest that under hypoxic conditions mast cells may contribute, at least in part, to an elevated expression of HIF-1alpha and VEGF protein in keloids via direct cell-cell interaction with fibroblasts.
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MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibroblastos/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Queloide , Mastócitos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Comunicação Celular/fisiologia , Hipóxia Celular/fisiologia , Células Cultivadas , Técnicas de Cocultura , Fibroblastos/citologia , Humanos , Queloide/patologia , Mastócitos/citologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Increasing evidence indicates that airway remodeling plays an important part in asthma pathogenesis. However, mechanisms underlying airway remodeling are not yet fully elucidated. Plasminogen activator inhibitor (PAI)-1 is the main inhibitor of the fibrinolytic system and is known to play an essential role in tissue remodeling. Recent evidence indicates that chronic asthma may lead to tissue remodeling such as subepithelial fibrosis and extracellular matrix (ECM) deposition in the airways. Recently, the mast cell (MC), which plays a major role in asthma, is found as a novel source of PAI-1 and a large number of MCs expressing PAI-1 are infiltrated in the airways of patients with severe asthma. Furthermore, PAI-1-deficient mice show reduced ECM deposition in the airways of a murine model of chronic asthma. In a human study, the 4G allele frequency was significantly higher in the asthmatic patients than in the control group. In view of the findings that the 4G allele is associated with elevated plasma PAI-1 level, elevated PAI-1 level in the lung may contribute to the development of airway remodeling. In summary, MCs may play an important role in the pathogenesis of asthma in part by producing PAI-1. Further studies evaluating the mechanisms of PAI-1 action may provide a new paradigm in airway remodeling and lead to the development of a novel therapeutic target.
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Mastócitos/imunologia , Mastócitos/metabolismo , Sistema Respiratório/imunologia , Sistema Respiratório/metabolismo , Animais , Asma/etiologia , Fibrinólise , Regulação da Expressão Gênica , Humanos , Mediadores da Inflamação/metabolismo , Metaloproteinases da Matriz/metabolismo , Camundongos , Inibidor 1 de Ativador de Plasminogênio/deficiência , Inibidor 1 de Ativador de Plasminogênio/genética , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Sistema Respiratório/citologiaRESUMO
BACKGROUND: Amphiregulin is a member of the epidermal growth factor family and has been shown to stimulate the proliferation of human keratinocytes in an autocrine manner. OBJECTIVE: The aim of the present study was to examine the expression change of growth factors, especially amphiregulin, in human mast cells induced by IgE cross-linking. METHODS: Microarray analysis and RT-PCR were used to analyze the gene expression profile of human cord blood-derived mast cells (CBMCs) stimulated with IgE cross-linking. Protein secretion in the supernatants of CBMCs was measured by means of ELISA. Double-immunofluorescence staining was used to analyze the expression in the lung mast cells. RESULTS: Of the 64 different growth factor genes analyzed, 5 were found to be substantially upregulated. Among them, amphiregulin mRNA was induced by 44-fold in CBMCs on activation through IgE cross-linking. Secretion of amphiregulin protein was evident in CBMCs 8 hours after stimulation. Amphiregulin was also expressed in human lung mast cells from patients with asthma, as demonstrated by means of double-immunofluorescence staining. Amphiregulin promoted the proliferation of the primary human lung fibroblasts, and amphiregulin-treated primary human lung fibroblasts showed a marked increase in the expression of c-fos , a proto-oncogene that facilitates or is required for the proliferation of a wide variety of cells. CONCLUSION: Human CBMCs secreted amphiregulin on IgE cross-linking, and the amphiregulin induced proliferation of primary human lung fibroblasts. These data suggest that local release of amphiregulin by human mast cells could play an important role in lung fibrosis by promoting the proliferation of primary human lung fibroblasts.
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Asma/metabolismo , Fibroblastos/citologia , Glicoproteínas/metabolismo , Glicoproteínas/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Pulmão/citologia , Mastócitos/metabolismo , Anfirregulina , Asma/patologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Sistemas Computacionais , Reagentes de Ligações Cruzadas/farmacologia , Família de Proteínas EGF , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica , Glicoproteínas/genética , Humanos , Imunoglobulina E , Peptídeos e Proteínas de Sinalização Intercelular/genética , Pulmão/patologia , Mastócitos/citologia , Miócitos de Músculo Liso/citologia , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , RNA Mensageiro/metabolismo , Proteínas Recombinantes/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
BACKGROUND: Racemic formoterol is an equimolar mixture of (R,R)- and (S,S)-formoterol. Several studies have shown (S,S)-formoterol to have proinflammatory effects. We previously reported that (S)-albuterol increased the secretion of histamine and interleukin (IL)-4 in murine mast cells. We thus hypothesized that (S,S)-formoterol promotes asthma by enhancing IL-4 production in mast cells of the asthmatic airway. METHODS: Murine and human mast cells were stimulated by high affinity IgE receptor (Fc epsilon RI) cross-linking or with phorbol myristate acetate/calcium ionophore A23187 (PMA/A23187). Jurkat T cells were stimulated with PMA. Cells were pretreated with either (R,R)- or (S,S)-formoterol. Ovalbumin (OVA)-sensitized BALB/c mice were pretreated with (R,R)- or (S,S)-formoterol before each intranasal OVA challenge for 10 days. Bronchoalveolar lavage fluid was obtained from the mice. The levels of IL-4, histamine and PGD(2) were measured. Early and late allergic responses (EAR and LAR, respectively) to OVA challenge and airway hyperresponsiveness (AHR) were measured. RESULTS: (S,S)-formoterol enhanced the production of IL-4, histamine, and PGD(2) in mast cells, whereas (R,R)-formoterol had no effect. Neither (S,S)- nor (R,R)-formoterol had effect on IL-4 production in Jurkat T cells. In OVA-challenged mice, (S,S)-formoterol increased IL-4 secretion, whereas (R,R)-formoterol had no effect. Finally, (S,S)-formoterol enhanced the inflammatory changes in the peribronchial and perivascular areas without affecting EAR, LAR or AHR, whereas (R,R)-formoterol reduced EAR, LAR and AHR as well as cellular infiltration in the lung tissue of these mice. CONCLUSION: (S,S)-formoterol may exert adverse effects in asthma control by activating mast cells to produce proinflammatory mediators such as IL-4.
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Asma/imunologia , Broncodilatadores/farmacologia , Etanolaminas/farmacologia , Interleucina-4/biossíntese , Mastócitos/efeitos dos fármacos , Mastócitos/imunologia , Animais , Asma/tratamento farmacológico , Asma/patologia , Testes de Provocação Brônquica , Líquido da Lavagem Broncoalveolar/imunologia , Modelos Animais de Doenças , Fumarato de Formoterol , Liberação de Histamina/efeitos dos fármacos , Liberação de Histamina/imunologia , Histocitoquímica , Humanos , Interleucina-4/imunologia , Interleucina-4/metabolismo , Células Jurkat , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Mastócitos/metabolismo , Mastócitos/patologia , Cloreto de Metacolina/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Prostaglandina D2/imunologia , Prostaglandina D2/metabolismo , Estereoisomerismo , Linfócitos T/imunologia , Linfócitos T/metabolismoRESUMO
Plasminogen activator inhibitor (PAI)-1 is the main inhibitor of the fibrinolytic system and is known to play an essential role in tissue remodeling. Recent evidence indicates that chronic asthma may lead to tissue remodeling such as subepithelial fibrosis and extracellular matrix (ECM) deposition in the airways. However, the role of PAI-1 in asthma is unknown. Recently the mast cell (MC), which plays a major role in asthma, was found as a novel source of PAI-1, and a large number of MCs expressing PAI-1 are infiltrated in the airways of patients with severe asthma. Furthermore, PAI-1-deficient mice show reduced ECM deposition in the airways of a murine model of chronic asthma by inhibiting MMP-9 activity and fibrinolysis. In a human study, the 4G allele frequency was significantly higher in the asthmatic patients than in the control group. In view of the findings that the 4G allele is associated with elevated plasma PAI-1 level, elevated PAI-1 level in the lung may contribute to the development of asthma. In summary, PAI-1 may play an important role in the pathogenesis of asthma and further studies evaluating the mechanisms of PAI-1 action may lead to the development of a novel therapeutic target for the treatment and prevention of asthma.
Assuntos
Asma/patologia , Inibidor 1 de Ativador de Plasminogênio/fisiologia , Animais , Asma/genética , Asma/imunologia , Asma/metabolismo , Fibrinólise/efeitos dos fármacos , Humanos , Desequilíbrio de Ligação/genética , Mastócitos/imunologia , Mastócitos/metabolismo , Mastócitos/patologia , Metaloendopeptidases/metabolismo , Ativadores de Plasminogênio/antagonistas & inibidores , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologiaRESUMO
Activin A, a homodimeric protein (betaAbetaA) and a member of the TGF-beta superfamily, is involved in the inflammatory repair process. Using cDNA microarray analysis, we discovered strong induction of the activin betaA gene in human mast cells (MC) on stimulation with PMA and calcium ionophore (A23187). Activin betaA mRNA was also highly induced in primary cultured murine bone marrow MC (BMMC) after stimulation by IgE receptor cross-linking. Secretion of activin A was evident in human mast cell-1 line cells 3 h after stimulation and progressively increased over time. Activin A was present in the cytoplasm of activated but not unstimulated murine bone marrow MC as demonstrated by immunofluorescence studies, suggesting that secretion of activin A by MC was due to de novo synthesis rather than secretion of preformed protein. Activin A also colocalized with human lung MC from patients with asthma by double-immunofluorescence staining. Furthermore, secretion of activin A was significantly increased in the airway of wild-type mice after OVA sensitization followed by intranasal challenge. Secretion of activin A, however, was greatly reduced in MC-deficient WBB6F(1)-W/W(v) mice as compared with wild-type mice, indicating that MC are an important contributor of activin A in the airways of a murine asthma model. Additionally, activin A promoted the proliferation of human airway smooth muscle cells. Taken together, these data suggest that MC-derived activin A may play an important role in the process of airway remodeling by promoting the proliferation of airway smooth muscle.
Assuntos
Ativinas/biossíntese , Asma/metabolismo , Subunidades beta de Inibinas/biossíntese , Pulmão/citologia , Pulmão/fisiologia , Mastócitos/metabolismo , Músculo Liso/citologia , Músculo Liso/fisiologia , Ativinas/genética , Ativinas/metabolismo , Ativinas/fisiologia , Animais , Asma/patologia , Northern Blotting , Células da Medula Óssea/química , Líquido da Lavagem Broncoalveolar/química , Divisão Celular/fisiologia , Linhagem Celular , Células Cultivadas , Citoplasma/metabolismo , Ensaio de Imunoadsorção Enzimática , Regulação da Expressão Gênica/fisiologia , Humanos , Subunidades beta de Inibinas/genética , Subunidades beta de Inibinas/metabolismo , Subunidades beta de Inibinas/fisiologia , Leucopenia/genética , Leucopenia/metabolismo , Leucopenia/patologia , Pulmão/metabolismo , Pulmão/patologia , Mastócitos/patologia , Camundongos , Camundongos Mutantes , Microscopia Confocal , Análise de Sequência com Séries de Oligonucleotídeos , Ovalbumina/administração & dosagem , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Mast cells not only function as effector cells but also influence nearly every other cell involved in causing allergic rhinitis. Mast cell-derived mediators such as histamine, bradykinin, tryptase, and the arachidonic acid derivatives produce the symptoms of the early-phase reaction of allergic rhinitis and also attract and activate other leukocytes involved in the late-phase reaction. In addition, activated mast cells are known to secrete a number of cytokines, both preformed and newly synthesized, that can modulate T- and B-cell function, propagate the early- and late-phase reactions, and contribute to tissue remodeling. Most currently available therapies work by antagonizing the mediators secreted by mast cells and other leukocytes. With the possible exception of immunotherapy, these therapies do not provide long-term protection against allergic disorders. Exciting new developments in gene-based therapies seem promising in both reducing and reversing the development of allergic rhinitis.
Assuntos
Grânulos Citoplasmáticos/enzimologia , Mastócitos/enzimologia , Rinite Alérgica Perene/etiologia , Rinite Alérgica Sazonal/etiologia , Serina Endopeptidases/fisiologia , Animais , Ácido Araquidônico/metabolismo , Quimases , Histamina/fisiologia , Humanos , Interleucinas/fisiologia , Rinite Alérgica Perene/tratamento farmacológico , Rinite Alérgica Sazonal/tratamento farmacológico , TriptasesRESUMO
Dysregulation of matrix metalloproteinases (MMPs) and ineffective fibrinolysis are associated with the deposition of extracellular matrix (ECM). We hypothesized that elevated plasminogen activator inhibitor (PAI)-1 promotes ECM deposition in the asthmatic airway by inhibiting MMP-9 activity and fibrinolysis. Degree of airway inflammation was similar in PAI-1(-/-) and wild type (WT) mice after ovalbumin (OVA) challenge. PAI-1 production, deposition of collagen and fibrin, and MMP-9 activity in the lung tissue or airways were greater after OVA challenge compared with saline challenge. However, in PAI-1(-/-) mice, collagen deposition was 2-fold less, fibrin deposition was 4-fold less, and MMP-9 activity was 3-fold higher. This is the first direct evidence that the plasmin system regulates ECM deposition in the airways of a murine asthma model, independently of the effect of PAI-1 on inflammatory cells. The results suggest that the PAI-1-dependent inhibition of MMP-9 activity and fibrinolysis is a major mechanism by which ECM deposition occurs.