RESUMO
BACKGROUND: Current techniques used to obtain lung samples have significant limitations and do not provide reproducible biomarkers of inflammation. We have developed a novel technique that allows multiple sampling methods from the same area (or multiple areas) of the lung under direct bronchoscopic vision. It allows collection of mucosal lining fluid and bronchial brushing from the same site; biopsy samples may also be taken. The novel technique takes the same time as standard procedures and can be conducted safely. METHODS: Eight healthy smokers aged 40-65 years were included in this study. An absorptive filter paper was applied to the bronchial mucosa under direct vision using standard bronchoscopic techniques. Further samples were obtained from the same site using bronchial brushings. Bronchoalveolar lavage (BAL) was obtained using standard techniques. Chemokine (C-C Motif) Ligand 20 (CCL20), CCL4, CCL5, Chemokine (C-X-C Motif) Ligand 1 (CXCL1), CXCL8, CXCL9, CXCL10, CXCL11, Interleukin 1 beta (IL-1ß), IL-6, Vascular endothelial growth factor (VEGF), Matrix metalloproteinase 8 (MMP-8) and MMP-9 were measured in exudate and BAL. mRNA was collected from the bronchial brushings for gene expression analysis. RESULTS: A greater than 10 fold concentration of all the biomarkers was detected in lung exudate in comparison to BAL. High yield of good quality RNA with RNA integrity numbers (RIN) between 7.6 and 9.3 were extracted from the bronchial brushings. The subset of genes measured were reproducible across the samples and corresponded to the inflammatory markers measured in exudate and BAL. CONCLUSIONS: The bronchoabsorption technique as described offers the ability to sample lung fluid direct from the site of interest without the dilution effects caused by BAL. Using this method we were able to successfully measure the concentrations of biomarkers present in the lungs as well as collect high yield mRNA samples for gene expression analysis from the same site. This technique demonstrates superior sensitivity to standard BAL for the measurement of biomarkers of inflammation. It could replace BAL as the method of choice for these measurements. This method provides a systems biology approach to studying the inflammatory markers of respiratory disease progression. TRIAL REGISTRATION: NHS Health Research Authority (13/LO/0256).
Assuntos
Broncoscopia/métodos , Mediadores da Inflamação/análise , Pulmão/patologia , Pneumonia/patologia , Fumar/efeitos adversos , Fumar/patologia , Manejo de Espécimes/métodos , Absorção Fisico-Química , Adulto , Idoso , Biomarcadores/análise , Líquido da Lavagem Broncoalveolar/química , Broncoscopia/instrumentação , Feminino , Perfilação da Expressão Gênica , Humanos , Pulmão/química , Masculino , Pessoa de Meia-Idade , Papel , Pneumonia/genética , Pneumonia/metabolismo , RNA Mensageiro/análise , Fumar/genética , Fumar/metabolismo , Manejo de Espécimes/instrumentaçãoRESUMO
BACKGROUND: SH2-containing inositol-5'-phosphatase 1 (SHIP1) is an endogenous inhibitor of the phosphoinositide-3-kinase pathway that is involved in the activation and chemotaxis of inflammatory cells. AQX-1125 is a first-in-class, oral SHIP1 activator with a novel anti-inflammatory mode of action. OBJECTIVE: To evaluate the effects of AQX-1125 on airway responses to allergen challenge in mild-to-moderate asthmatic patients. METHODS: A randomized, double-blind, placebo-controlled, two-way crossover study was performed in 22 steroid-naïve mild-to-moderate asthmatics with a documented late-phase response to inhaled allergen (LAR). AQX-1125 (450 mg daily) or placebo was administered orally for 7 days. Allergen challenge was performed on day 6 (2 h postdose), followed by methacholine challenge (day 7), and induced sputum collection and fractional exhaled nitric oxide (FeNO). RESULTS: AQX-1125 significantly attenuated the late-phase response compared with placebo (FEV1 4-10 h: mean difference 150 mL, 20%; P = 0.027) and significantly increased the minimum FEV1 during LAR (mean difference 180 mL; P = 0.014). AQX-1125 had no effect on the early-phase response. AQX-1125 showed a trend in reduction of sputum eosinophils, neutrophils and macrophages although this did not achieve significance as there were only 11 paired samples for analysis. There was no effect on methacholine responsiveness or FeNO. Pharmacokinetic data showed AQX-1125 was rapidly absorbed with geometric mean Cmax and AUC0-24 h values of 1417 ng/mL and 16 727 h ng/mL, respectively. AQX-1125 was well tolerated, but mild GI side-effects (dyspepsia, nausea and abdominal pain) were described in 4/22 subjects on active treatment. These side-effects were mild self-limiting, required no further treatment and did not lead to discontinuation of therapy. CONCLUSION AND CLINICAL RELEVANCE: AQX-1125, a novel oral SHIP1 activator, significantly reduces the late response to allergen challenge, with a trend to reduce airway inflammation. AQX-1125 was safe and well tolerated and merits further investigation in inflammatory disorders.
Assuntos
Alérgenos/imunologia , Asma/tratamento farmacológico , Asma/imunologia , Cicloexanóis/farmacologia , Cicloexanóis/uso terapêutico , Indanos/farmacologia , Indanos/uso terapêutico , Adulto , Alérgenos/administração & dosagem , Análise de Variância , Antiasmáticos/farmacologia , Antiasmáticos/uso terapêutico , Asma/diagnóstico , Asma/metabolismo , Testes de Provocação Brônquica , Estudos Cross-Over , Expiração , Feminino , Volume Expiratório Forçado , Humanos , Inositol Polifosfato 5-Fosfatases , Masculino , Óxido Nítrico/metabolismo , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases , Fosfatidilinositóis/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Fatores de Risco , Índice de Gravidade de Doença , Transdução de Sinais , Escarro , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: CRTH2 is a G-protein-coupled receptor on T helper2 cells that mediates pro-inflammatory effects of prostaglandin D2 in allergic responses. OBJECTIVE: To investigate the tolerability and pharmacokinetics of setipiprant (ACT-129968), a selective orally active CRTH2 antagonist, in allergic asthmatics and to assess the protective effects of multiple doses of this drug against allergen-induced airway responses. METHODS: In this 3-centre, double-blinded, placebo-controlled, cross-over study, 18 allergic asthmatic males were randomized to setipiprant 1000 mg or matching placebo b.i.d. for 5 consecutive days. Study periods were separated by a washout of ≥ 3 weeks. On study day 4, subjects underwent a standardized allergen challenge and airway response was recorded by FEV1 until 10 h post-allergen. Airway responsiveness to methacholine and exhaled nitric oxide (eNO) were measured pre- and post-dosing. The effects of both treatments on the allergen-induced airway responses were compared by a paired Student's t-test. RESULTS: Fifteen subjects completed the study per-protocol and were included in the analysis. Overall, setipiprant was well tolerated and no clinically relevant adverse events occurred. Trough plasma concentrations showed a high inter-subject variability. Compared with placebo, setipiprant significantly reduced the allergen-induced late asthmatic response (LAR), inhibiting the area under the response vs. time curve (AUC(3-10 h) ) by on average 25.6% (P = 0.006) and significantly protected against the allergen-induced airway hyperresponsiveness (AHR) to methacholine (P = 0.0029). There was no difference in the early asthmatic response (EAR) or in allergen-induced changes in eNO between treatments. CONCLUSION AND CLINICAL RELEVANCE: Setipiprant at multiple oral doses was well tolerated and reduced both the allergen-induced LAR and the associated AHR in allergic asthmatics. Our findings confirm that CRTH2 may be a promising target for the treatment of allergic disorders.
Assuntos
Alérgenos/imunologia , Asma/tratamento farmacológico , Asma/imunologia , Indóis/farmacologia , Indóis/uso terapêutico , Naftalenos/farmacologia , Naftalenos/uso terapêutico , Receptores Imunológicos/antagonistas & inibidores , Receptores de Prostaglandina/antagonistas & inibidores , Adulto , Antiasmáticos/farmacologia , Antiasmáticos/uso terapêutico , Asma/diagnóstico , Testes de Provocação Brônquica , Expiração , Volume Expiratório Forçado/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Testes de Função Respiratória , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: GSK2190915, a potent 5-lipoxygenase-activating protein inhibitor, prevents the synthesis of leukotrienes and 5-oxo-6,8,11,14-eicosatetraenoic acid (5-oxo-ETE). OBJECTIVE: To assess the effect of GSK2190915 on the allergen-induced asthmatic responses. METHODS: Nineteen eligible male subjects with mild asthma were enrolled in and completed this four-centre, double-blind, two-way crossover study (ClinicalTrials.gov NCT00748306). Subjects took GSK2190915 100 mg and placebo orally once daily for 5 days in randomized order. On Day 1 and 4 they had a methacholine challenge, on Day 3 they had an inhaled allergen challenge, and on Days 4 and 6 they had sputum induction. RESULTS: GSK2190915 attenuated the early (0-2 h) and late (4-10 h) asthmatic responses to inhaled allergen compared with placebo. There was a statistically significant attenuation of the early asthmatic response (EAR) by GSK2190915; treatment difference of GSK2190915 vs. placebo for the minimum FEV(1) EAR was 0.408 L (0.205, 0.611). There was a statistically significant attenuation of the late asthmatic response (LAR) by GSK2190915; the treatment difference of GSK2190915 vs. placebo for the minimum FEV(1) LAR was 0.229 L (0.041, 0.417). There was a statistically significant attenuation of allergen-induced sputum eosinophil count on Day 4 following GSK2190915: mean treatment difference (95% CI) between GSK2190915 and placebo was -9.95% (-18.15%, -1.77%). Compared with placebo, GSK2190915 100 mg reduced median sputum LTB(4) by > 90% on Days 4 and 6. There was no effect on methacholine PC(20) post allergen. GSK2190915 was generally well tolerated. CONCLUSION AND CLINICAL RELEVANCE: GSK2190915 shows potential as a treatment for patients with asthma.
Assuntos
Inibidores da Proteína Ativadora de 5-Lipoxigenase/uso terapêutico , Alérgenos/efeitos adversos , Asma/tratamento farmacológico , Indóis/metabolismo , Indóis/uso terapêutico , Ácidos Pentanoicos/metabolismo , Ácidos Pentanoicos/uso terapêutico , Inibidores da Proteína Ativadora de 5-Lipoxigenase/farmacologia , Adulto , Alérgenos/administração & dosagem , Asma/imunologia , Testes de Provocação Brônquica , Humanos , Indóis/administração & dosagem , Leucotrieno B4/sangue , Leucotrieno B4/urina , Masculino , Ácidos Pentanoicos/administração & dosagem , Testes de Função Respiratória , Escarro/imunologia , Resultado do Tratamento , Adulto JovemRESUMO
Bronchial mucosal CD8(+) cells are implicated in chronic obstructive pulmonary disease (COPD) pathogenesis, but there are few data on their functional properties. We have developed a novel technique to outgrow these cells from COPD patients in sufficient numbers to examine effector functions. Endobronchial biopsies from 15 COPD smokers and 12 ex-smokers, 11 control smokers and 10 non-smokers were cultured with anti-CD3/interleukin (IL)-2 ± IL-15. Outgrown CD3(+) T cells were characterized in terms of phenotype (expression of CD4, 8, 25, 28, 69 and 56), cytotoxicity and expression of COPD-related cytokines. Compared with IL-2 alone, additional IL-15 increased the yield and viability of biopsy-derived CD3(+) T cells (12-16-day culture without restimulation) without alteration of CD4(+) /CD8(+) ratios or expression of accessory/activation molecules. Biopsy-derived T cells, principally CD8(+)/CD56(+) cells, exhibited statistically significantly greater cytotoxic activity in current or ex-smokers with COPD compared with controls (P < 0·01). Elevated percentages of CD8(+) T cells expressed interferon (IFN)-γ, tumour necrosis factor (TNF)-α and IL-13 (P < 0·01) in current COPD smokers compared with all comparison groups. It is possible to perform functional studies on bronchial mucosal T cells in COPD. We demonstrate increased CD8(+)CD56(+) T cell cytotoxic activity and expression of remodelling cytokines in smokers who develop COPD.
Assuntos
Citocinas/imunologia , Citotoxicidade Imunológica/imunologia , Doença Pulmonar Obstrutiva Crônica/imunologia , Linfócitos T/imunologia , Adulto , Idoso , Biópsia , Brônquios/imunologia , Brônquios/patologia , Complexo CD3/imunologia , Complexo CD3/metabolismo , Técnicas de Cultura de Células/métodos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Feminino , Citometria de Fluxo , Humanos , Imunofenotipagem , Interleucina-12/farmacologia , Interleucina-15/farmacologia , Células K562 , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/patologia , Mucosa Respiratória/imunologia , Mucosa Respiratória/patologia , Fumar , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismoRESUMO
BACKGROUND: The combination of salmeterol and fluticasone propionate (SFC) and tiotropium bromide (TIO) are commonly used treatments in chronic obstructive pulmonary disease (COPD) but there are few data on their effectiveness when used together. We compared the effects of SFC 50/500 microg twice daily in addition to TIO 18 microg once daily with the individual treatments alone. METHODS: 41 patients with COPD participated in a randomised, double blind, double dummy, three way crossover study with 2 week washout periods between treatments. Lung function assessment included plethysmography and spirometry. The primary end point was post-dose specific airways conductance (sGaw) area under the curve (AUC(0-4 h)) on day 14. RESULTS: AUC(0-4 h) sGaw was significantly higher on day 14 after SFC+TIO compared with TIO (22%) or SFC alone (27%) (both p<0.001). SFC+TIO significantly improved trough forced expiratory volume in 1 s compared with TIO alone (212 ml, p<0.001) and SFC alone (110 ml, p = 0.017) on day 14. Inspiratory capacity measurements also showed significant benefits for triple therapy over individual components on day 14. Subjects receiving SFC+TIO had clinically relevant improvements in Transition Dyspnoea Index (TDI) total score of 2.2 compared with TIO alone (p<0.001) (but not SFC alone, 0.7; NS) and used significantly less rescue medication (1.0 occasion less daily than TIO (p<0.001) and 0.6 less than SFC (p = 0.01)). CONCLUSION: SFC+TIO triple therapy led to greater improvements in bronchodilation compared with TIO and SFC alone. The advantages of triple therapy are observed across a range of physiologically important parameters, including airway conductance and lung volumes. Triple therapy also led to patient related benefits by improving TDI and use of rescue medication.
Assuntos
Albuterol/análogos & derivados , Androstadienos/uso terapêutico , Broncodilatadores/uso terapêutico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Derivados da Escopolamina/uso terapêutico , Adulto , Idoso , Albuterol/uso terapêutico , Estudos Cross-Over , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Fluticasona , Volume Expiratório Forçado/fisiologia , Humanos , Medidas de Volume Pulmonar/métodos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Xinafoato de Salmeterol , Brometo de Tiotrópio , Resultado do Tratamento , Capacidade Vital/fisiologiaRESUMO
Asthmatics, unlike healthy subjects, experience bronchoconstriction in response to inhaled adenosine, and extracellular adenosine concentrations are elevated in the bronchoalveolar lavage fluid and exhaled breath condensate of asthmatic subjects. However, little is known about the location and expression of adenosine receptors in asthmatic airways. The aim of the present study was to investigate the distribution of adenosine A(1) receptors in bronchial biopsy specimens from mildly asthmatic steroid-naïve subjects and then compare the degree of expression with that of healthy subjects. Biopsy sections were immunostained using an adenosine A(1) receptor antibody, the selectivity of which was validated in specific experiments. Image analysis was then performed in order to determine differences in immunostaining intensity. Immunostaining of biopsy sections from the asthmatic subjects revealed strong expression of the A(1) receptor, located predominantly in the bronchial epithelium and bronchial smooth muscle. In comparison, very weak immunostaining was observed in biopsy specimens obtained from healthy subjects. Image analysis revealed that the intensity of positive staining of the asthmatic bronchial epithelium and smooth muscle regions was significantly greater than that observed for the healthy epithelium and smooth muscle. In conclusion, the sensitivity of asthmatics to inhaled adenosine coupled with increased adenosine A(1) receptor expression implies that these receptors play a role in the pathophysiology of this disease.
Assuntos
Asma/fisiopatologia , Brônquios/patologia , Hiper-Reatividade Brônquica/diagnóstico , Receptor A1 de Adenosina/metabolismo , Adenosina/administração & dosagem , Administração por Inalação , Asma/patologia , Biomarcadores/análise , Biópsia por Agulha , Testes de Provocação Brônquica , Estudos de Casos e Controles , Feminino , Volume Expiratório Forçado , Humanos , Imuno-Histoquímica , Masculino , Prognóstico , Receptor A1 de Adenosina/análise , Valores de Referência , Testes de Função Respiratória , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Medição de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Regulação para CimaRESUMO
BACKGROUND AND PURPOSE: The glycosaminoglycan heparin has anti-inflammatory activity and is exclusively found in mast cells, which are localized within airway smooth muscle (ASM) bundles of asthmatic airways. Interleukin (IL)-13 induces the production of multiple inflammatory mediators from ASM including the eosinophil chemoattractant chemokine, eotaxin-1. Heparin and related glycosaminoglycan polymers having structurally heterogeneous polysaccharide side chains that varied in molecular weight, sulphation and anionic charge were used to identify features of the heparin molecule linked to anti-inflammatory activity. EXPERIMENTAL APPROACH: Cultured human ASM cells were stimulated with interleukin (IL)-13 in the absence or presence of heparin and related polymers. Eotaxin-1 was quantified using chemokine antibody arrays and ELISA. KEY RESULTS: Unfractionated heparin attenuated IL-13-dependent eotaxin-1 production and this effect was reproduced with low molecular weight heparins (3 and 6 kDa), demonstrating a minimum activity fragment of at least 3 kDa. N-desulphated, 20% re-N-acetylated heparin (anticoagulant) was ineffective against IL-13-dependent eotaxin-1 production compared with 90% re-N-acetylated (anticoagulant) or O-desulphated (non-anticoagulant) heparin, suggesting a requirement for N-sulphation independent of anticoagulant activity. Other sulphated molecules with variable anionic charge and molecular weight exceeding 3 kDa (dextran sulphate, fucoidan, chondroitin sulphate B) inhibited IL-13-stimulated eotaxin-1 release to varying degrees. However, non-sulphated dextran had no effect. CONCLUSIONS: Inhibition of IL-13-dependent eotaxin-1 release by heparin involved but did not depend upon sulphation, though loss of N-sulphation reduced the attenuating activity, which could be restored by N-acetylation. This anti-inflammatory effect was also partially dependent on anionic charge, but independent of molecular size above 3 kDa and the anticoagulant action of heparin.
Assuntos
Anti-Inflamatórios/farmacologia , Anticoagulantes/farmacologia , Quimiocina CCL11/efeitos dos fármacos , Heparina/farmacologia , Miócitos de Músculo Liso/efeitos dos fármacos , Adulto , Idoso , Ânions/química , Anti-Inflamatórios/química , Anticoagulantes/química , Células Cultivadas , Quimiocina CCL11/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Heparina/química , Heparina de Baixo Peso Molecular/química , Heparina de Baixo Peso Molecular/farmacologia , Humanos , Interleucina-13/farmacologia , Masculino , Pessoa de Meia-Idade , Peso Molecular , Sulfatos/químicaRESUMO
BACKGROUND: Inhaled endotoxin or lipopolysaccharide (LPS) is implicated in the pathogenesis of pulmonary diseases. We investigated the inhalation effects of two different doses of LPS in healthy human subjects. METHODS: Eighteen healthy non-atopic human subjects inhaled either 15 microg (n=10) or 50 microg (n=8)Escherichia coli LPS in an open study. As control, each subject had isotonic saline inhalation 1 week before (baseline) and after LPS inhalation. Data collected included those of clinical parameter, induced sputum and peripheral blood CD4+ and CD8+ T cells. RESULTS: Acute flu-like symptoms and pyrexia were significantly greater in the 50 microg than 15 microg LPS group. Similarly, the increase in sputum and blood total cell and neutrophil counts at 6h following inhaled LPS were greater in the 50 microg group. Myeloperoxidase, human neutrophil elastase and interleukin-8 in sputum sol, but not blood, showed a trend towards greater increase following 50 microg LPS. All these changes were resolved at one week. In the 50 microg dose group alone, there was a reduction in the proportion of peripheral blood interferon (IFN)-gamma-producing CD4+ and CD8+ T cells at 6h followed by an increase at 1 week after inhaled LPS. CONCLUSIONS: The airway and systemic effects of inhaled LPS are dose-related and predominantly neutrophilic. The changes in the proportions of circulating CD4+ and CD8+ T cells suggests preferential recruitment of IFN-gamma-producing T cells into tissue from inhaled 50 microg LPS, followed by reappearance of these cells in blood 1 week later.
Assuntos
Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Lipopolissacarídeos/efeitos adversos , Administração por Inalação , Adulto , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Relação Dose-Resposta a Droga , Feminino , Humanos , Lipopolissacarídeos/administração & dosagem , Contagem de Linfócitos , Masculino , Escarro/citologiaRESUMO
To study the nature of endotoxin or lipopolysaccharide (LPS) induced inflammation, we developed a method of quantifying intracellular human neutrophil elastase (HNE) in lysed sputum polymorphs as a means to study the degranulation status of LPS-recruited neutrophils. Induced sputum, blood and exhaled nitric oxide (NO) were collected from 10 healthy non-atopic human subjects after inhaling a single 15 microg dose of Escherichia coil LPS in an open study. At 6 hours, LPS inhalation caused significant increase of sputum and blood neutrophils but without parallel increase in myeloperoxidase, HNE or interleukin-8 (IL-8) in sputum sol and blood, or exhaled NO. Intracellular HNE in lysed sputum polymorphs or purified blood neutrophils did not show any significant changes between inhaled LPS and saline, nor was there any appreciable change in percentage HNE release induced by N-Formyl-Met-Leu-Phe (fMLP) in vitro. We concluded that in healthy humans, the transient neutrophilic inflammation induced by a single dose of inhaled 15 microg LPS is mainly characterized by cell recruitment, not enhanced secretion of granular mediators or increased exhaled NO based on our experimental conditions.
Assuntos
Degranulação Celular/efeitos dos fármacos , Endotoxinas/farmacologia , Neutrófilos/fisiologia , Administração por Inalação , Adulto , Movimento Celular , Técnicas Citológicas/métodos , Endotoxinas/administração & dosagem , Escherichia coli , Humanos , Inflamação , Elastase de Leucócito/análise , Lipopolissacarídeos/administração & dosagem , Lipopolissacarídeos/farmacologia , Masculino , Neutrófilos/efeitos dos fármacos , Neutrófilos/enzimologia , Óxido Nítrico/análise , EscarroRESUMO
Hyperresponsiveness of airway smooth muscle accounts for the susceptibility of asthmatic subjects to diverse bronchoconstrictor agents. It is widely presumed that hyperresponsiveness is not spasmogen selective. Hence, inhalation of methacholine is used routinely for clinical assessment of asthma and for evaluation of anti-asthma drugs. Comparative studies employing multiple spasmogens have revealed hyperresponsiveness to be markedly spasmogen selective. Because of this pronounced heterogeneity of hyperresponsiveness, sensitivity to methacholine cannot provide a reliable index of responsiveness. Development of exceptional hyperresponsiveness to bradykinin and to peptidoleukotrienes during allergic and other reactions could warrant the development of specific antagonists for asthma therapy. These issues are discussed here by Brian O'Connor, Simon Crowther, John Costello and John Morley.
Assuntos
Asma/fisiopatologia , Hiper-Reatividade Brônquica/induzido quimicamente , Broncoconstritores/farmacologia , Albuterol/farmacologia , Animais , Asma/tratamento farmacológico , Bradicinina , Hiper-Reatividade Brônquica/fisiopatologia , Broncoconstritores/uso terapêutico , Broncodilatadores/farmacologia , Humanos , Leucotrieno C4 , Cloreto de MetacolinaRESUMO
Sputum induction with nebulized hypertonic saline is increasingly being used to evaluate airway inflammation. We investigated the procedure-associated risk in 16 asthmatics that were still symptomatic despite on high doses of regular corticosteroid (CS) therapy (7 on daily inhaled CS > or = 800 microg budesonide or equivalent; 9 on additional daily oral CS) and their sputum cellular profile. For comparison, 12 mild stable asthmatics and 10 normal healthy subjects were included. All subjects inhaled 3%, 4% and 5% hypertonic saline sequentially via ultrasonic nebulizer as a means to induce sputum. Maximal percentage fall of Forced Expiratory Volume on One Second (FEV1) during sputum induction was significantly greater in CS-dependent asthmatics (median % [IQR]: 16.0 [11.0-32.3]) than in mild asthmatics (5.3 [4.2-10.8], p = 0.002] and in normal subjects (4.6 [3.4-6.4]), p = 0.0001). The maximal percentage FEV1 fall was inversely correlated with baseline FEV1 (Rs= -0.69; p < 0.0001). Compared to mild asthmatics, induced sputum from CS-dependant asthmatics had proportionately fewer eosinophils (2.2 [0.8-7.0] versus 23.3% [10.7-46.3], p = 0.003) and greater neutrophils (64.2 [43.9-81.2] versus 28.7 [19.0-42.6], p = 0.009). Sputum neutrophils showed a significant inverse correlation to FEV1 (Rs = -0.51, p = 0.01). We concluded that sputum induction using nebulized hypertonic saline should be performed with caution in CS-dependant asthmatics. The airway cellular profile observed suggests that the immunopathology underlying CS-dependant asthmatics may be different or a consequence of CS therapy.
Assuntos
Asma/imunologia , Broncodilatadores/uso terapêutico , Budesonida/uso terapêutico , Solução Salina Hipertônica/administração & dosagem , Escarro/citologia , Corticosteroides/uso terapêutico , Adulto , Anti-Inflamatórios/uso terapêutico , Asma/tratamento farmacológico , Asma/fisiopatologia , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Nebulizadores e VaporizadoresRESUMO
1. The aim of the present study was to investigate the role of adenosine A2b receptors in the anti-proliferative action of theophylline in human peripheral blood mononuclear cells (HPBMC) from healthy and asthmatic subjects. 2. Theophylline significantly inhibited PHA-induced proliferation of HPBMC from both healthy and asthmatic donors but only at relatively high concentrations at 1 mM (P<0.05). Enprophylline, a drug which also acts as a non-selective phosphodiesterase (PDE) inhibitor and is a selective A2b receptor antagonist, had no significant effect on proliferation of cells from either group at concentrations up to 10 microM (P>0.05; n=6). 3. Adenosine deaminase (2 u ml(-1)), which metabolizes adenosine, had no significant effect on PHA-induced HPBMC proliferation over a range of concentrations (0 - 8 microg ml(-1)) in cells from either healthy or asthmatic subjects. 4. The adenosine receptor agonists N(6)-cyclopentyladenosine (CPA, A1-selective) and 5'-N-ethylcarboxamidoadenosine (NECA, A1/A2) produced a small but significant inhibition of PHA-induced proliferation of HPBMC from healthy and asthmatic subjects (10 microM, P<0.05; n=6). In contrast, 5'-N-ethylcarboxamido-2-[4-(2-]carboxyethyl)phenethyl]adenosine (CGS21680, A2a-selective) was without significant effect (P>0.05; n=6). 5. The adenosine receptor antagonist alloxazine (A2b-selective) had no significant effect, while 8(3-chlorostyryl)caffeine,(CSC, A2a-selective) significantly inhibited PHA-induced proliferation of HPBMC from both groups (P<0.05; n=6). 6. Our results suggest that endogenous or exogenous adenosine has little effect on the proliferation of HPBMC obtained from healthy or asthmatic subjects. Thus it would appear that the effect of high concentrations of theophylline is not related to adenosine receptor antagonism.
Assuntos
Asma/metabolismo , Monócitos/metabolismo , Agonistas do Receptor Purinérgico P1 , Antagonistas de Receptores Purinérgicos P1 , Teofilina/farmacologia , Adenosina Desaminase/farmacologia , Divisão Celular/efeitos dos fármacos , Humanos , Técnicas In Vitro , Monócitos/efeitos dos fármacos , Inibidores de Fosfodiesterase/farmacologia , Fito-Hemaglutininas/farmacologia , Receptor A2B de AdenosinaRESUMO
In the present study, for the first time, PDE4 subtypes were identified and semi-quantified in both CD4 and CD8 lymphocytes from healthy and asthmatic individuals. CD4 and CD8 lymphocytes from healthy and mild asymptomatic asthmatic subjects (receiving beta-agonist therapy only) were isolated from peripheral venous blood using appropriate antibody coated paramagnetic beads. PDE4 subtypes and beta-actin were identified by digoxigenin (DIG)-labelling reverse transcriptase-polymerase chain reaction and semi-quantified by DIG-detection enzyme-linked immunosorbance assay. In CD4 and CD8 lymphocytes PDE4A, PDE4B and PDE4D were detected, with no significant differences observed between healthy and asthmatic groups. In CD8 lymphocytes, enzyme subtype expression was lower and showed more intersubject variability. In functional studies investigating the effects of various PDE inhibitors on PHA-induced proliferation of mononuclear cells from healthy and asthmatic subjects, CDP840 (0.03 - 10 microM), rolipram (0.1 - 10 microM) and theophylline (10 microM - 1 mM) inhibited PHA-induced proliferation of mononuclear cells from healthy and asthmatic subjects in a concentration-dependent manner, although no significant difference was observed between the groups investigated. In additional studies, total monocyte cyclic AMP PDE activity was investigated in cells isolated from asthmatic subjects both prior to and 24 h after allergen challenge. Total monocyte cyclic AMP PDE activity remained unaffected following challenge of asthmatic subjects with either house dust mite or cat dander and was inhibited in a concentration-dependent manner by rolipram (0.01 - 100 microM) both before and after allergen challenge.
Assuntos
3',5'-AMP Cíclico Fosfodiesterases/metabolismo , Asma/enzimologia , Linfócitos T CD4-Positivos/enzimologia , Linfócitos T CD8-Positivos/enzimologia , 3',5'-AMP Cíclico Fosfodiesterases/efeitos dos fármacos , 3',5'-AMP Cíclico Fosfodiesterases/genética , Adolescente , Adulto , Alérgenos/farmacologia , Divisão Celular/efeitos dos fármacos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3 , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4 , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Feminino , Regulação Enzimológica da Expressão Gênica , Humanos , Isoenzimas/efeitos dos fármacos , Isoenzimas/genética , Isoenzimas/metabolismo , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Masculino , Inibidores de Fosfodiesterase/farmacologia , Fito-Hemaglutininas/farmacologia , Piridinas/farmacologia , RNA/genética , RNA/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rolipram/farmacologia , Teofilina/farmacologiaRESUMO
The mandatory requirement to eliminate chlorofluorocarbons (CFCs) as propellants in pharmaceutical aerosols has provided the opportunity to enhance significantly the delivery of aerosol drugs to the respiratory tract. This randomized, parallel-group, double-blind, double-dummy, multicentre study was undertaken to assess whether beclomethasone dipropionate (BDP) in hydrofluoroalkane-134a (HFA) provided equivalent control of moderately severe asthma to BDP in CFC but at approximately half the total daily dose, as might be expected from the improved lung deposition of the HFA-BDP extrafine aerosol. The novel study design included a 10-12 day run-in period to confirm that patients met established criteria of moderately severe asthma and were symptomatic on current therapy (inhaled beta-agonist plus CFC-BDP 400-800 micrograms day-1). This run-in period was followed by a short course of oral steroid therapy (prednisolone 30 mg day-1 for 7-13 days) to demonstrate steroid responsiveness [> or = 15% improvement in morning peak expiratory flow (PEF)] and to provide a within-study baseline of improved asthma control. A total of 233 patients were randomized to treatment for 12 weeks with HFA-BDP 800 micrograms day-1 (116 patients) or CFC-BDP 1500 micrograms day-1 (117 patients). The mean change from oral steroid treatment in morning PEF with HFA-BDP was equivalent to that seen with CFC-BDP at all time intervals. Changes in other measures of pulmonary function, asthma symptom scores and beta-agonist use were equivalent in the two treatment groups throughout the 12 week treatment period. The safety profile of HFA-BDP compared favourably with that of CFC-BDP with no unexpected adverse events reported. Fewer patients on HFA-BDP than on CFC-BDP had plasma cortisol levels below the normal reference range after 12 weeks of therapy (5.1% vs. 17.3%, respectively). In conclusion, HFA-BDP extrafine aerosol was found to provide equivalent control of moderately severe asthma to CFC-BDP at approximately half the daily dose with a favourable safety profile, suggesting an improved therapeutic ratio.
Assuntos
Propelentes de Aerossol , Anti-Inflamatórios/administração & dosagem , Asma/tratamento farmacológico , Beclometasona/administração & dosagem , Hidrocarbonetos Fluorados , Administração por Inalação , Agonistas Adrenérgicos beta/uso terapêutico , Adulto , Aerossóis , Idoso , Anti-Inflamatórios/uso terapêutico , Asma/sangue , Beclometasona/uso terapêutico , Clorofluorcarbonetos , Método Duplo-Cego , Esquema de Medicação , Quimioterapia Combinada , Humanos , Hidrocortisona/sangue , Pessoa de Meia-IdadeRESUMO
In inflammatory cells, the low K(m) cyclic adenosine monophosphate (cAMP)-specific phosphodiesterase (PDE) 4 subtype is predominant in terms of expression and function, although more recently it has been suggested that PDE 7 may also play a role in regulating inflammatory cell activity. In the present study, PDE 4 and PDE 7 subtype messenger ribonucleic acid (mRNA) transcripts in CD4 and CD8 lymphocytes from healthy (n=10) and asthmatic (n=10) subjects and polymorphonuclear neutrophils (PMNs) and CD8 lymphocytes obtained from healthy (n=10) and chronic obstructive pulmonary disease (COPD) (n=7) subjects were identified and quantified. PDE 4A, PDE 4B, PDE 4D and PDE 7A mRNA were present in similar quantities in both CD4 and CD8 lymphocytes obtained from healthy and asthmatic subjects and in CD8 lymphocytes obtained from healthy and COPD subjects. Expression of PDE 4C and PDE 7B mRNA was also observed, although transcript levels were low and variable between individuals. In addition, the effects of selective PDE 7 inhibition on both phytohaemagluttinin (PHA)-induced human peripheral blood mixed mononuclear cell (HPBMNC) proliferation and fMLP-induced neutrophil elastase (NE) release were studied. HPBMNC and human neutrophils, isolated from the venous blood of healthy volunteers (n=6) were treated with either a novel selective PDE 7 inhibitor PF 0332040 alone or in combination with rolipram. Proliferation of HPBMNC was stimulated by PHA (2microgml(-1)) and assessed by [(3)H]-thymidine incorporation, while fMLP-induced (100nM) NE release was determined using a chromogenic substrate. Both rolipram (0.003-10microM) and PF 0332040 (0.003-10microM) significantly inhibited PHA-stimulated proliferation of HPBMNC ((**)P<0.01). Co-administration of rolipram (0.3-10microM) and PF 0332040 (0.003-10microM) significantly increased the degree of inhibition observed, compared to when either drug was administered alone ((**)P<0.01). PF 0332040 (0.003-10microM) had no inhibitory effect on NE release from human peripheral blood neutrophils stimulated with fMLP (100nM), while rolipram (0.003-10microM) significantly inhibited neutrophil degranulation ((**)P<0.01). These findings suggest no evidence of altered PDE 4 or PDE 7 mRNA transcript levels in inflammatory cells isolated from the peripheral venous blood of mild asymptomatic asthmatic subjects or stable COPD subjects, however, inhibition of PDE 7 may influence mononuclear cell function.
Assuntos
3',5'-AMP Cíclico Fosfodiesterases/genética , Asma/sangue , Leucócitos/metabolismo , Doença Pulmonar Obstrutiva Crônica/sangue , 3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , 3',5'-AMP Cíclico Fosfodiesterases/metabolismo , Adulto , Idoso , Benzamidas/farmacologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Proliferação de Células/efeitos dos fármacos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4 , Nucleotídeo Cíclico Fosfodiesterase do Tipo 7 , Relação Dose-Resposta a Droga , Feminino , Humanos , Elastase de Leucócito/genética , Elastase de Leucócito/metabolismo , Leucócitos/citologia , Leucócitos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Inibidores de Fosfodiesterase/farmacologia , Fito-Hemaglutininas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Rolipram/farmacologia , Tiadiazóis/farmacologiaRESUMO
In many countries the majority of patients with asthma are now treated with inhaled beta 2-agonists as required and regular inhaled steroids. Compliance with asthma medication is poor, particularly for inhaled steroids, which do not give immediate relief of symptoms. An inhaler combining a beta 2-agonist and a steroid may improve compliance and give better control of asthma. We have studied the effect of a fixed combination dry powder inhaler (Turbuhaler) containing terbutaline (250 micrograms) with budesonide (200 micrograms) compared with each drug given alone in a double-blind, crossover study in 74 patients with mild to moderate asthma. This was a multicenter study performed in general practice. After a 1-wk run-in period with placebo inhaler, each treatment was given twice daily for 4 wk in randomized order. Patients measured symptom scores and rescue inhaled beta 2-agonist use and recorded peak expiratory flow (PEF) twice daily. In nine patients recruited to a hospital center, airway responsiveness was measured by the concentration of methacholine required to produce a fall in FEV1 of 20% (PC20) at the end of each treatment period. Of 74 patients randomized, 68 completed all three treatment periods. Their mean age was 37 (18-60) yr and PEF 80 (43-116) % predicted. Combination treatment gave a significant improvement in morning and evening PEF budesonide or terbutaline treatment periods (p < 0.01), and a significant reduction in asthma symptom scores and rescue beta 2-agonist use (p < 0.05). There was a significant patient preference for the combination inhaler.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Asma/tratamento farmacológico , Broncodilatadores/uso terapêutico , Pregnenodionas/uso terapêutico , Terbutalina/uso terapêutico , Adolescente , Adulto , Budesonida , Estudos Cross-Over , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do PacienteRESUMO
Nonalcoholic steatohepatitis (NASH) is the term used for a common form of fatty liver presenting in adults with varied clinical manifestations. The most common presentation is asymptomatic elevation of liver enzymes (AST or SGOT and ALT or SGPT), which can be discovered incidentally in the course of an annual checkup, life insurance examination, or as part of surrogate screening before blood donation. At the other end of the clinical spectrum is the patient with complications from cryptogenic cirrhosis, who also shows a lack of evidence of alcohol as an etiological factor in pathogenesis. Clinical associations of probable relevance include gender (female), obesity, diabetes, and hyperlipidemia, but many patients do not conform to any of these stereotypes (e.g., young men of normal weight with normal fasting glucose and lipid levels). Liver biopsy confirms the diagnosis of NASH, the association of steatosis with an inflammatory response being the sine qua non for the condition and "creeping fibrosis" being a variable but possibly sinister feature. Newer imaging techniques may provide convincing evidence of steatosis, but they give little insight into ongoing fibrosis, and liver biopsy therefore remains the gold standard. The mainstay of treatment remains judicious weight loss coupled with positive dietary advice, including the ingestion of adequate but not excessive vitamins. After initial encouraging data. the assessment of ursodeoxycholic acid currently being studied under randomized controlled conditions is eagerly awaited.
Assuntos
Fígado Gorduroso , Adulto , Causalidade , Fígado Gorduroso/diagnóstico , Fígado Gorduroso/epidemiologia , Fígado Gorduroso/terapia , Feminino , Humanos , Fígado/patologia , Masculino , Prevalência , SíndromeRESUMO
There has been controversy about possible beneficial effects of beta agonists on airway function in asthma, in addition to their effects on airway smooth muscle. We compared the protective effects of terbutaline on bronchoconstrictor responses to methacholine, which constricts smooth muscle directly, adenosine 5'-monophosphate (AMP), which acts indirectly by mast cell activation, and sodium metabisulfite (MBS), which stimulates sensory nerves, in 15 mild asthmatic subjects in a randomized double-blind study carried out in two phases. In the first phase 12 subjects inhaled two doses of 0.5 and 2.5 mg terbutaline or placebo administered as a dry power (Tubohaler) 20 min before challenge with methacholine and AMP. Each subject received increasing doubling doses of methacholine and AMP nebulized from a dosimeter. Challenges were terminated when FEV1 fell by 20% from baseline (PC20). In the second phase 10 subjects (seven of whom had participated in Phase 1) inhaled 0.5 mg terbutaline or placebo before similar challenge with methacholine and MBS. In Phase 1 terbutaline inhibited the bronchoconstrictor response to methacholine by 2.1 and 3.3 doubling doses but caused a significantly greater inhibition of the response to AMP of 3.4 and 4.8 doubling doses after 0.5 and 2.5 mg, respectively. In the second phase 0.5 mg terbutaline had equivalent effects on responses to both methacholine and MBS of 2.6 and 2.2 doubling dilutions, respectively. This effect on methacholine and MBS implies functional antagonism of airway smooth muscle. The enhanced effect on AMP implies an additional non-smooth muscle action that may involve suppression of airway mast cell function.