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1.
NPJ Prim Care Respir Med ; 26: 16038, 2016 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-27442488

RESUMO

Inhaled corticosteroid/long-acting ß2-agonist (ICS/LABA) fixed-dose combinations are recommended regular maintenance options for asthma. ICS/LABAs containing formoterol may also be indicated for single maintenance and reliever therapy (SMART). This analysis evaluated the frequency of SMART dosing of budesonide/formoterol fixed-dose combination (BFC) in the United Kingdom. Secondary objectives were to assess adherence and use of short-acting ß2-agonists (SABAs). This was a descriptive analysis of treatment patterns using the UK Clinical Practice Research Datalink-GP OnLine Database data (2009-2013). SMART dosing was determined when prescription instructions contained guidance for daily dosing plus 'and when required'. Treatment and prescription refill patterns of BFC and SABA were described in the year following the index date to identify adherence and SMART dosing instructions versus other dosing regimens. Of 14,818 patients identified, 173 (1.2%) had evidence of prescriptions for SMART dosing at their index BFC prescription. Despite being prescribed SMART dosing, 91 of 173 patients (53%) were additionally dispensed SABA in the year following the index date. The mean number of BFC inhalers used was less than required for daily treatment for SMART and non-SMART dosing groups (4.7 and 4.8, respectively).This analysis suggests that SMART dosing is infrequent when examining dosing instructions. Therefore, results of randomised clinical trials using SMART dosing may not translate to clinical practice in the United Kingdom because of the low level of SMART prescription, concurrent use of SABA, and inadequate refill persistence observed. Further research is needed to understand SMART dosing in real-world clinical practice.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Fidelidade a Diretrizes/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Adolescente , Adulto , Idoso , Antiasmáticos/administração & dosagem , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reino Unido , Adulto Jovem
2.
Lancet Respir Med ; 3(9): 684-691, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26149841

RESUMO

BACKGROUND: Lung delivery of plasmid DNA encoding the CFTR gene complexed with a cationic liposome is a potential treatment option for patients with cystic fibrosis. We aimed to assess the efficacy of non-viral CFTR gene therapy in patients with cystic fibrosis. METHODS: We did this randomised, double-blind, placebo-controlled, phase 2b trial in two cystic fibrosis centres with patients recruited from 18 sites in the UK. Patients (aged ≥12 years) with a forced expiratory volume in 1 s (FEV1) of 50-90% predicted and any combination of CFTR mutations, were randomly assigned, via a computer-based randomisation system, to receive 5 mL of either nebulised pGM169/GL67A gene-liposome complex or 0.9% saline (placebo) every 28 days (plus or minus 5 days) for 1 year. Randomisation was stratified by % predicted FEV1 (<70 vs ≥70%), age (<18 vs ≥18 years), inclusion in the mechanistic substudy, and dosing site (London or Edinburgh). Participants and investigators were masked to treatment allocation. The primary endpoint was the relative change in % predicted FEV1. The primary analysis was per protocol. This trial is registered with ClinicalTrials.gov, number NCT01621867. FINDINGS: Between June 12, 2012, and June 24, 2013, we randomly assigned 140 patients to receive placebo (n=62) or pGM169/GL67A (n=78), of whom 116 (83%) patients comprised the per-protocol population. We noted a significant, albeit modest, treatment effect in the pGM169/GL67A group versus placebo at 12 months' follow-up (3.7%, 95% CI 0.1-7.3; p=0.046). This outcome was associated with a stabilisation of lung function in the pGM169/GL67A group compared with a decline in the placebo group. We recorded no significant difference in treatment-attributable adverse events between groups. INTERPRETATION: Monthly application of the pGM169/GL67A gene therapy formulation was associated with a significant, albeit modest, benefit in FEV1 compared with placebo at 1 year, indicating a stabilisation of lung function in the treatment group. Further improvements in efficacy and consistency of response to the current formulation are needed before gene therapy is suitable for clinical care; however, our findings should also encourage the rapid introduction of more potent gene transfer vectors into early phase trials. FUNDING: Medical Research Council/National Institute for Health Research Efficacy and Mechanism Evaluation Programme.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/administração & dosagem , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/tratamento farmacológico , Terapia Genética/métodos , Plasmídeos/administração & dosagem , Administração por Inalação , Adolescente , Adulto , Criança , Fibrose Cística/genética , Fibrose Cística/fisiopatologia , Método Duplo-Cego , Feminino , Volume Expiratório Forçado/efeitos dos fármacos , Humanos , Lipossomos , Masculino , Mutação , Nebulizadores e Vaporizadores , Reino Unido , Adulto Jovem
4.
Thorax ; 68(6): 532-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23396354

RESUMO

BACKGROUND: Clinical trials in cystic fibrosis (CF) have been hindered by the paucity of well characterised and clinically relevant outcome measures. AIM: To evaluate a range of conventional and novel biomarkers of CF lung disease in a multicentre setting as a contributing study in selecting outcome assays for a clinical trial of CFTR gene therapy. METHODS: A multicentre observational study of adult and paediatric patients with CF (>10 years) treated for a physician-defined exacerbation of CF pulmonary symptoms. Measurements were performed at commencement and immediately after a course of intravenous antibiotics. Disease activity was assessed using 46 assays across five key domains: symptoms, lung physiology, structural changes on CT, pulmonary and systemic inflammatory markers. RESULTS: Statistically significant improvements were seen in forced expiratory volume in 1 s (p<0.001, n=32), lung clearance index (p<0.01, n=32), symptoms (p<0.0001, n=37), CT scores for airway wall thickness (p<0.01, n=31), air trapping (p<0.01, n=30) and large mucus plugs (p=0.0001, n=31), serum C-reactive protein (p<0.0001, n=34), serum interleukin-6 (p<0.0001, n=33) and serum calprotectin (p<0.0001, n=31). DISCUSSION: We identify the key biomarkers of inflammation, imaging and physiology that alter alongside symptomatic improvement following treatment of an acute CF exacerbation. These data, in parallel with our study of biomarkers in patients with stable CF, provide important guidance in choosing optimal biomarkers for novel therapies. Further, they highlight that such acute therapy predominantly improves large airway parameters and systemic inflammation, but has less effect on airway inflammation.


Assuntos
Antibacterianos/administração & dosagem , Fibrose Cística/tratamento farmacológico , Volume Expiratório Forçado/fisiologia , Pneumopatias/tratamento farmacológico , Pulmão/fisiopatologia , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Antibacterianos/uso terapêutico , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Criança , Fibrose Cística/diagnóstico , Fibrose Cística/fisiopatologia , Feminino , Humanos , Injeções Intravenosas , Interleucina-6/sangue , Complexo Antígeno L1 Leucocitário/sangue , Pulmão/diagnóstico por imagem , Pneumopatias/diagnóstico , Pneumopatias/fisiopatologia , Masculino , Recidiva , Resultado do Tratamento , Adulto Jovem
5.
Am J Respir Crit Care Med ; 183(4): 491-9, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20870753

RESUMO

RATIONALE: Bronchiectasis is a chronic debilitating disease with few evidence-based long-term treatments. OBJECTIVES: A randomized controlled trial assessing the efficacy of nebulized gentamicin therapy over 1 year in patients with non-cystic fibrosis bronchiectasis. METHODS: Sixty-five patients were randomized to either twice-daily nebulized gentamicin, 80 mg, or nebulized 0.9% saline, for 12 months. All were reviewed at three-monthly intervals during treatment and at 3 months' follow-up. MEASUREMENTS AND MAIN RESULTS: At each review the following were assessed: quantitative and qualitative sputum bacteriology; sputum purulence and 24-hour volume; FEV(1), FVC, and forced expiratory flow, midexpiratory phase; exercise capacity; Leicester Cough Questionnaire and St. George's Respiratory Questionnaire; and exacerbation frequency. Fifty-seven patients completed the study. At the end of 12 months' treatment, compared with the saline group, in the gentamicin group there was reduced sputum bacterial density with 30.8% eradication in those infected with Pseudomonas aeruginosa and 92.8% eradication in those infected with other pathogens; less sputum purulence (8.7% vs. 38.5%; P < 0.0001); greater exercise capacity (510 [350-690] m vs. 415 [267.5-530] m; P = 0.03); and fewer exacerbations (0 [0-1] vs. 1.5 [1-2]; P < 0.0001) with increased time to first exacerbation (120 [87-161.5] d vs. 61.5 [20.7-122.7] d; P = 0.02). The gentamicin group had greater improvements in Leicester Cough Questionnaire (81.4% vs. 20%; P < 0.01) and St. George's Respiratory Questionnaire (87.5% vs. 19.2%; P < 0.004) score. No differences were seen in 24-hour sputum volume, FEV(1), FVC, or forced expiratory flow, midexpiratory phase. No P. aeruginosa isolates developed resistance to gentamicin. At follow-up, all outcome measures were similar to baseline. CONCLUSIONS: Regular, long-term nebulized gentamicin is of significant benefit in non-cystic fibrosis bronchiectasis but treatment needs to be continuous for its ongoing efficacy. Clinical trial registered with www.clinicaltrials.gov (NCT 00749866).


Assuntos
Antibacterianos/administração & dosagem , Bronquiectasia/tratamento farmacológico , Gentamicinas/administração & dosagem , Administração por Inalação , Aerossóis , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória/métodos , Testes de Função Respiratória/estatística & dados numéricos , Cloreto de Sódio/administração & dosagem , Inquéritos e Questionários , Resultado do Tratamento
6.
Thorax ; 65(8): 747-52, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20581409

RESUMO

The use of a combination inhaler containing budesonide and formoterol as both maintenance and quick relief therapy (SMART) has been recommended as an improved method of using inhaled corticosteroid/long-acting beta agonist (ICS/LABA) therapy. Published double-blind trials show that budesonide/formoterol therapy delivered in SMART fashion achieves better asthma outcomes than budesonide monotherapy or lower doses of budesonide/formoterol therapy delivered in constant dosage. Attempts to compare budesonide/formoterol SMART therapy with regular combination ICS/LABA dosing using other compounds have been confounded by a lack of blinding and unspecified dose adjustment strategies. The asthma control outcomes in SMART-treated patients are poor; it has been reported that only 17.1% of SMART-treated patients are controlled. In seven trials of 6-12 months duration, patients using SMART have used quick reliever daily (weighted average 0.92 inhalations/day), have awakened with asthma symptoms once every 7-10 days (weighted average 11.5% of nights), have suffered asthma symptoms more than half of days (weighted average 54.0% of days) and have had a severe exacerbation rate of one in five patients per year (weighted average 0.22 severe exacerbations/patient/year). These poor outcomes may reflect the recruitment of a skewed patient population. Although improvement from baseline has been attributed to these patients receiving additional ICS therapy at pivotal times, electronic monitoring has not been used to test this hypothesis nor the equally plausible hypothesis that patients who are non-compliant with maintenance medication have used budesonide/formoterol as needed for self-treatment of exacerbations. Although the long-term consequences of SMART therapy have not been studied, its use over 1 year has been associated with significant increases in sputum and biopsy eosinophilia. At present, there is no evidence that better asthma treatment outcomes can be obtained by moment-to-moment symptom-driven use of ICS/LABA therapy than conventional physician-monitored and adjusted ICS/LABA therapy.


Assuntos
Asma/tratamento farmacológico , Broncodilatadores/administração & dosagem , Budesonida/administração & dosagem , Etanolaminas/administração & dosagem , Administração por Inalação , Agonistas Adrenérgicos beta/administração & dosagem , Método Duplo-Cego , Combinação de Medicamentos , Fumarato de Formoterol , Glucocorticoides/administração & dosagem , Humanos , Cooperação do Paciente , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Resultado do Tratamento
7.
Chest ; 137(3): 635-41, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19801580

RESUMO

BACKGROUND: Induced sputum cytology and protein biomarkers can be used to assess airways inflammation. Increases in sputum iron have been described in inflammatory lung disease. We hypothesized that other sputum metals may be affected by airways inflammation and investigated their potential value as biomarkers. METHODS: Sputum was obtained from 20 healthy control subjects and from patients with inflammatory pulmonary diseases (23 with cystic fibrosis [CF], 16 with bronchiectasis, 17 with asthma, and 23 with COPD), and iron, zinc, manganese, and copper were measured. Fourteen patients with CF were also studied through an exacerbation cycle. RESULTS: Sputum zinc and iron were elevated in CF and non-CF bronchiectasis vs controls (P < .001, zinc; P < .01 iron). Manganese was elevated in asthma (P < .01) and bronchiectasis (P < .05) vs controls. Copper was elevated in CF vs controls (P < .05). Zinc decreased (P < .01) following treatment of CF exacerbation. In subjects with CF zinc levels correlated with other biomarkers. CONCLUSIONS: These results suggest a relationship of high concentrations of total zinc and iron with airways inflammation in CF and non-CF bronchiectasis, with longitudinal changes being observed in CF. Further work is required to elucidate potential inflammatory mechanisms related to these observations.


Assuntos
Asma/diagnóstico , Biomarcadores/análise , Bronquiectasia/diagnóstico , Fibrose Cística/diagnóstico , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Escarro/química , Oligoelementos/análise , Adulto , Idoso , Asma/metabolismo , Bronquiectasia/metabolismo , Cobre/análise , Fibrose Cística/metabolismo , Diagnóstico Diferencial , Feminino , Humanos , Ferro/análise , Masculino , Manganês/análise , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/metabolismo , Reprodutibilidade dos Testes , Análise Espectral , Supuração , Zinco/análise
8.
Respir Physiol Neurobiol ; 162(3): 197-203, 2008 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-18625345

RESUMO

S(cond) and S(acin) are derived from analysis of concentration-normalized phase III slopes (Sn(III)) of a multiple breath inert gas washout. Studies in healthy and COPD subjects suggest these reflect ventilation heterogeneity in conducting and acinar airway zones respectively, but similar studies in cystic fibrosis (CF) are lacking. S(cond), S(acin) and lung clearance index (LCI, a measure of overall gas mixing efficiency) were measured in 22 adults and 18 children with CF and 17 adult and 29 child controls. Plethysmography and gas transfer measurements were performed in adults, and spirometry in all subjects. S(cond) was elevated in almost all CF patients, including children with mild disease and normal LCI. However, S(cond) did not correlate with other measurements and appeared to reach a maximum; further increase in ventilation heterogeneity being restricted to S(acin). The nature and/or severity of CF lung disease may invalidate assumptions underlying the ability to separate phase III slope analysis of ventilation heterogeneity into proximal and peripheral components, and LCI may be a better indicator of gas mixing in this population.


Assuntos
Fibrose Cística/diagnóstico , Fibrose Cística/fisiopatologia , Ventilação Pulmonar/fisiologia , Respiração/efeitos dos fármacos , Testes de Função Respiratória/métodos , Adolescente , Adulto , Fatores Etários , Criança , Pré-Escolar , Feminino , Volume Expiratório Forçado , Humanos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pletismografia , Ventilação Pulmonar/efeitos dos fármacos , Adulto Jovem
9.
Am J Respir Crit Care Med ; 178(5): 444-52, 2008 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-18565957

RESUMO

RATIONALE: Markers of inflammatory activity are important for assessment and management of many respiratory diseases. Markers that are currently unrecognized may be more valuable than those presently believed to be useful. OBJECTIVES: To identify potential biomarkers of suppurative and inflammatory lung disease in induced sputum samples. METHODS: Induced sputum was collected from 20 healthy control subjects, 24 patients with asthma, 24 with chronic obstructive pulmonary disease, 28 with cystic fibrosis (CF), and 19 with bronchiectasis. Twelve patients with CF had sputum sampled before and after antibiotic therapy for an infective exacerbation. The fluid phase of induced sputum was analyzed by surface-enhanced laser desorption/ionization time-of-flight (SELDI-TOF) mass spectroscopy on three protein array surfaces. Some protein markers were selected for identification, and relevant ELISA assays sought. For 12 patients with CF, both SELDI-TOF and ELISA monitored changes in inflammatory responses during infective exacerbations. MEASUREMENTS AND MAIN RESULTS: SELDI-TOF identified potential biomarkers that differentiated each of the disease groups from healthy control subjects: at a significance of P < 0.01, there were 105 for asthma, 113 for chronic obstructive pulmonary disease, 381 for CF, and 377 for bronchiectasis. Peaks selected for protein identification yielded calgranulin A, calgranulin B, calgranulin C, Clara cell secretory protein, lysosyme c, proline rich salivary peptide, cystatin s, and hemoglobin alpha. On treatment of an infective CF exacerbation, SELDI-TOF determined falls in levels of calgranulin A and calgranulin B that were mirrored by ELISA-measured falls in calprotectin (heterodimer of calgranulins A and B). CONCLUSIONS: Proteomic screening of sputum yields potential biomarkers of inflammation. The early development of a clinically relevant assay from such data is demonstrated.


Assuntos
Biomarcadores/metabolismo , Broncopatias/diagnóstico , Pneumopatias/diagnóstico , Mapeamento de Peptídeos , Escarro/química , Adulto , Idoso , Asma/diagnóstico , Bronquiectasia/diagnóstico , Estudos de Casos e Controles , Fibrose Cística/diagnóstico , Feminino , Humanos , Inflamação , Complexo Antígeno L1 Leucocitário/metabolismo , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Mapeamento de Peptídeos/métodos , Proteômica , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Supuração
10.
J Cyst Fibros ; 7(5): 352-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18243068

RESUMO

BACKGROUND: For cystic fibrosis (CF) patients there is a lack of good assays of disease activity and response to new therapeutic interventions, including gene therapy. Current measures of airways inflammation severity are insensitive or non-specific. METHODS: Bronchoalveolar lavage fluid from 39 CF children and 38 respiratory disease controls was obtained at bronchoscopy and analysed by surface enhanced laser desorption ionisation time of flight (SELDI-TOF) mass spectrometry. Recognized proteins were assessed for CF disease specificity. Individual protein identification of specific peaks was performed. RESULTS: 1277 proteins/peptides, >4 kDa, were detected using 12 different surfaces and binding conditions. 202 proteins/peptides were differentially expressed in the CF samples (p<0.001), 167 up-regulated and 35 down-regulated. The most discriminatory biomarker had a mass of 5.163 kDa. The most abundant, with a mass of 10.6 kDa, was identified as s100 A8 (calgranulin A). CONCLUSIONS: The application of SELDI-TOF mass spectrometry allows evaluation of proteins in BAL fluid avoiding the limitations of only analysing predetermined proteins and potentially identifying proteins not previously appreciated as biomarkers. Its application to cystic fibrosis should enable appropriate evaluation of evolving illness, of gene therapy and other new therapies.


Assuntos
Biomarcadores/análise , Líquido da Lavagem Broncoalveolar/química , Fibrose Cística/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Broncoscopia , Estudos de Casos e Controles , Criança , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Proteômica
11.
Respir Med ; 102(1): 143-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17869079

RESUMO

BACKGROUND: Treatment of acute asthma is based on rapid reversal of bronchospasm and airway inflammation. Magnesium sulphate (MgSO(4)) is known to have a bronchodilator effect on smooth muscle but studies have shown conflicting results on its efficacy in acute asthma, although its use is recommended in national and international guidelines. AIMS: To determine if intravenous MgSO(4), when used as an adjunct to standard therapy, improves the outcome in acute asthma. METHODS: A double blind, randomised placebo controlled trial comparing 1.2g MgSO(4) with standard therapy in adult patients with acute asthma. Patients had a PEF

Assuntos
Antiasmáticos/administração & dosagem , Asma/tratamento farmacológico , Sulfato de Magnésio/administração & dosagem , Doença Aguda , Adolescente , Adulto , Idoso , Vias de Administração de Medicamentos , Métodos Epidemiológicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Resultado do Tratamento
12.
BMJ ; 327(7420): 891, 2003 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-14563743

RESUMO

OBJECTIVES: To assess the effect of montelukast versus salmeterol added to inhaled fluticasone propionate on asthma exacerbation in patients whose symptoms are inadequately controlled with fluticasone alone. Design and setting A 52 week, two period, double blind, multicentre trial during which patients whose symptoms remained uncontrolled by inhaled corticosteroids were randomised to add montelukast or salmeterol. PARTICIPANTS: Patients (15-72 years; n = 1490) had a clinical history of chronic asthma for > or = 1 year, a baseline forced expiratory volume in one second (FEV1) value 50-90% predicted, and a beta agonist improvement of > or = 12% in FEV1. MAIN OUTCOME MEASURES: The primary end point was the percentage of patients with at least one asthma exacerbation. RESULTS: 20.1% of the patients in the group receiving montelukast and fluticasone had an asthma exacerbation compared with 19.1% in the group receiving salmeterol and fluticasone; the difference was 1% (95% confidence interval -3.1% to 5.0%). With a risk ratio (montelukast-fluticasone/salmeterol-fluticasone) of 1.05 (0.86 to 1.29), treatment with montelukast and fluticasone was shown to be non-inferior to treatment with salmeterol and fluticasone. Salmeterol and fluticasone significantly increased FEV1 before a beta agonist was used and morning peak expiratory flow compared with montelukast and fluticasone (P < or = 0.001), whereas FEV1 after a beta agonist was used and improvements in asthma specific quality of life and nocturnal awakenings were similar between the groups. Montelukast and fluticasone significantly (P = 0.011) reduced peripheral blood eosinophil counts compared with salmeterol and fluticasone. Both treatments were generally well tolerated. CONCLUSION: The addition of montelukast in patients whose symptoms remain uncontrolled by inhaled fluticasone could provide equivalent clinical control to salmeterol.


Assuntos
Acetatos/administração & dosagem , Albuterol/análogos & derivados , Albuterol/administração & dosagem , Androstadienos/administração & dosagem , Antiasmáticos/administração & dosagem , Asma/prevenção & controle , Broncodilatadores/administração & dosagem , Quinolinas/administração & dosagem , Acetatos/efeitos adversos , Adolescente , Adulto , Idoso , Albuterol/efeitos adversos , Androstadienos/efeitos adversos , Antiasmáticos/efeitos adversos , Asma/fisiopatologia , Broncodilatadores/efeitos adversos , Ciclopropanos , Método Duplo-Cego , Quimioterapia Combinada , Fluticasona , Volume Expiratório Forçado/efeitos dos fármacos , Humanos , Pessoa de Meia-Idade , Quinolinas/efeitos adversos , Xinafoato de Salmeterol , Sulfetos , Resultado do Tratamento
13.
Blood ; 100(8): 3008-16, 2002 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-12351415

RESUMO

Neutrophil apoptosis represents a major mechanism involved in the resolution of acute inflammation. In contrast to the effect of hypoxia observed in many other cell types, oxygen deprivation, as we have shown, causes a profound but reversible delay in the rate of constitutive apoptosis in human neutrophils when aged in vitro. This effect was mimicked by exposing cells to 2 structurally unrelated iron-chelating agents, desferrioxamine (DFO) and hydroxypyridines (CP-94), and it appeared specific for hypoxia in that no modulation of apoptosis was observed with mitochondrial electron transport inhibitors, glucose deprivation, or heat shock. The involvement of chelatable iron in the oxygen-sensing mechanism was confirmed by the abolition of the DFO and CP-94 survival effect by Fe(2+) ions. Although hypoxia inducible factor-1alpha (HIF-1alpha) mRNA was identified in freshly isolated neutrophils, HIF-1alpha protein was only detected in neutrophils incubated under hypoxic conditions or in the presence of DFO. Moreover, studies with cyclohexamide demonstrated that the survival effect of hypoxia was fully dependent on continuing protein synthesis. These results indicate that the neutrophil has a ferroprotein oxygen-sensing mechanism identical to that for erythropoietin regulation and results in HIF-1alpha up-regulation and profound but reversible inhibition of neutrophil apoptosis. This finding may have important implications for the resolution of granulocytic inflammation at sites of low-oxygen tension.


Assuntos
Apoptose/fisiologia , Hipóxia Celular/fisiologia , Desferroxamina/farmacologia , Quelantes de Ferro/farmacologia , Neutrófilos/fisiologia , Peptídeos/genética , Adrenomedulina , Apoptose/efeitos dos fármacos , Sequência de Bases , Hipóxia Celular/efeitos dos fármacos , Células Cultivadas , Primers do DNA , Glucose/farmacologia , Humanos , Interleucina-8/sangue , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Peptídeos/sangue , Piridinas/farmacologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica
14.
Chest ; 121(5): 1421-6, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12006423

RESUMO

STUDY OBJECTIVES: To investigate whether differing airway interleukin (IL)-18 levels may be implicated in the pathogenesis of asthma and sarcoidosis. SETTING: University teaching hospital. PATIENTS AND METHODS: IL-18 levels were measured in BAL fluid and in the supernatant of lipopolysaccharide (LPS)-stimulated alveolar macrophages obtained by BAL from 15 patients with sarcoidosis, 11 patients with asthma, and 13 healthy subjects. We also examined the relationship between IL-18 levels and macrophage and lymphocyte concentrations in BAL fluid. IL-18 was measured using an in-house enzyme-linked immunosorbent assay. RESULTS: IL-18 levels were significantly lower in BAL fluid from patients with asthma (median, 0.0 pg/mL; interquartile range, 0.0 to 0.0 pg/mL) compared to patients with sarcoidosis (median, 222.0 pg/10(6); interquartile range, 110 to 340 pg/mL; p = 0.009, Mann Whitney rank-sum test) and healthy control subjects (median, 162 pg/mL; interquartile range, 38 to 203 pg/mL; p = 0.025, Mann Whitney rank-sum test). Individual analyses comparing IL-18 levels with BAL macrophage counts, and IL-18 with lymphocyte counts in the three groups showed no correlation between these indexes. The mean levels of IL-18 in unstimulated macrophage supernatants were 410 pg/10(6) cells for patients with asthma, 723.4 pg/10(6) cells for patients with sarcoidosis, and 734.8 pg/10(6) cells for healthy control subjects (p > 0.05). Stimulated macrophages from patients with sarcoidosis responded with increasing amounts of IL-18 at lower doses of LPS than macrophages from healthy control subjects or patients with asthma. CONCLUSION: Our findings suggest that inherently low levels of IL-18 may be associated with the pathogenesis of asthmatic airway inflammation.


Assuntos
Asma/metabolismo , Líquido da Lavagem Broncoalveolar/química , Interleucina-18/análise , Sarcoidose Pulmonar/metabolismo , Adulto , Líquido da Lavagem Broncoalveolar/citologia , Contagem de Células , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Humanos , Linfócitos , Macrófagos , Macrófagos Alveolares/metabolismo , Pessoa de Meia-Idade
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