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2.
Artículo en Inglés | MEDLINE | ID: mdl-29956665

RESUMEN

BACKGROUND: Cough is a common feature of asthma, which is often resistant to inhaled corticosteroids (ICSs). The pathophysiology of this refractoriness may differ between daytime and nighttime asthmatic cough. We sought to identify factors contributing to ICS-refractory daytime and nighttime asthmatic cough. METHODS: Sixty-seven patients with asthma presenting solely or predominantly with chronic cough were prospectively enrolled from April 2012 to December 2014. At baseline and 12 weeks after ICS treatment, the capsaicin cough threshold (C2, C5) and methacholine airway sensitivity and reactivity were examined. A visual analog scale (VAS) and numeric scores were used to evaluate daytime and nighttime cough symptoms separately. The Japanese version of the Leicester Cough Questionnaire was also completed. When either the VAS or numeric scores showed an improvement of ≥50% or ≥2 points, patients were considered responders to ICS treatment. RESULTS: Fifty-five patients were eligible for evaluation. Subjective cough indices improved significantly at 12 weeks after ICS treatment (P<.001). Multivariate analysis revealed that lower C2 significantly contributed to residual daytime cough (P=.04). Meanwhile, methacholine hyperreactivity and lower IgE levels were predictors of the nighttime residual cough (P=.002 and P=.03, respectively). CONCLUSIONS: Heightened cough reflex sensitivity is an independent factor of daytime asthmatic cough that is refractory to ICSs. In contrast, airway hyperreactivity and less atopic status contribute to ICS-refractory nighttime cough.


Asunto(s)
Asma/complicaciones , Tos/etiología , Administración por Inhalación , Corticoesteroides/uso terapéutico , Adulto , Anciano , Antiasmáticos/uso terapéutico , Asma/tratamiento farmacológico , Tos/tratamiento farmacológico , Resistencia a Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores de Tiempo
3.
Clin Exp Allergy ; 47(8): 998-1006, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28326636

RESUMEN

BACKGROUND: Genetic markers of susceptibility to asthma exacerbations in adults remain unclear. OBJECTIVE: To identify genetic markers of asthma exacerbations, particularly in patients with type-2 inflammatory endotype. METHODS: In this observational study of patients enrolled in the Kinki Hokuriku Airway disease Conference multicenter study, frequency of exacerbations requiring systemic corticosteroids during 2 years after enrolment and associated risk factors was determined. For genetic marker analysis, interleukin-4 receptor α (IL4RA) rs8832 and a disintegrin and metalloprotease 33 (ADAM33) S_2 (rs528557), T_1 (rs2280091), T_2 (rs2280090), and V_4 (rs2787094) variants were included. Elevated serum periostin levels at enrolment (≥95 ng/mL, defined as type-2 inflammatory endotype) were considered in the analysis. RESULTS: Among 217 patients who were successfully followed up for 2 years after enrolment, 60 patients showed at least one asthma exacerbation during the 2 years. Airflow limitation (%FEV1 <80%) and recent exacerbations but not genetic variants were identified as risk markers of exacerbations. A total of 27 patients showed type-2 inflammatory endotype (serum periostin ≥95 ng/mL at enrolment) and subsequent exacerbations; risk factors in these patients were airflow limitation (odds ratio, 6.51; 95% confidence interval (CI): 2.37-18.6; P=.0003), GG genotype of IL4RA rs8832 (odds ratio, 4.01; 95% CI: 1.47-11.0; P=.007), and A allele of ADAM33 T_2 (odds ratio, 2.81; 95% CI: 1.05-7.67; P=.04) by multivariate analysis. In addition, GG genotype of IL4RA rs8832 was associated with type-2 endotype, whereas A allele of ADAM33 T_2 was associated with mixed type of eosinophilic/type-2 and neutrophilic inflammations. CONCLUSIONS AND CLINICAL RELEVANCE: IL4RA and ADAM33 variants may be risk markers of asthma exacerbations in type-2 inflammatory endotype. Precise endotyping may facilitate the identification of genetic risk markers of asthma exacerbations.


Asunto(s)
Proteínas ADAM , Asma/sangre , Asma/genética , Subunidad alfa del Receptor de Interleucina-4 , Proteínas ADAM/sangre , Proteínas ADAM/genética , Adulto , Anciano , Asma/tratamiento farmacológico , Estudios de Seguimiento , Marcadores Genéticos , Humanos , Subunidad alfa del Receptor de Interleucina-4/sangre , Subunidad alfa del Receptor de Interleucina-4/genética , Persona de Mediana Edad , Factores de Riesgo
4.
Allergy ; 71(10): 1472-9, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27113353

RESUMEN

BACKGROUND: Omalizumab, a humanized anti-IgE monoclonal antibody, has demonstrated efficacy in patients with severe allergic asthma. However, treatment responses vary widely among individuals. Despite a lack of data, free serum IgE levels following omalizumab treatment have been proposed as a marker of treatment responsiveness. METHODS: In this prospective, observational study, we assessed the utility of biomarkers of type 2 inflammation in predicting omalizumab treatment responses, as determined by the absence of asthma exacerbation during the first year of treatment. Free serum IgE levels were monitored for 2 years to examine their association with baseline biomarker levels and the number of exacerbations. RESULTS: We enrolled thirty patients who had been treated with omalizumab for at least 1 year, of whom 27 were treated for 2 years. Baseline serum periostin levels and blood eosinophil counts were significantly higher in patients without exacerbations during the first year of treatment than in patients with exacerbations. Baseline serum periostin levels, but not eosinophil counts, were negatively associated with free serum IgE levels after 16 or 32 weeks of treatment. Reduced free serum IgE levels during treatment from those at baseline were associated with reduced exacerbation numbers at 2 years. In 14 patients who continued to have exacerbations during the first year of treatment, exacerbation numbers gradually and significantly decreased over the 2-year study period, with concurrent significant reductions in free serum IgE levels. CONCLUSION: Baseline serum periostin levels and serum free IgE levels during treatment follow-up may be useful in evaluating responses to omalizumab treatment.


Asunto(s)
Antiasmáticos/uso terapéutico , Asma/sangre , Asma/tratamiento farmacológico , Moléculas de Adhesión Celular/sangre , Inmunoglobulina E/sangre , Omalizumab/uso terapéutico , Adulto , Anciano , Antiasmáticos/farmacología , Asma/diagnóstico , Asma/inmunología , Biomarcadores , Progresión de la Enfermedad , Femenino , Humanos , Inmunoglobulina E/inmunología , Masculino , Persona de Mediana Edad , Omalizumab/farmacología , Curva ROC , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
5.
Allergy ; 71(7): 1031-6, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26991116

RESUMEN

BACKGROUND: Allergic rhinitis, a known risk factor for asthma onset, often accompanies mouth breathing. Mouth breathing may bypass the protective function of the nose and is anecdotally considered to increase asthma morbidity. However, there is no epidemiological evidence that mouth breathing is independently associated with asthma morbidity and sensitization to allergens. In this study, we aimed to clarify the association between mouth breathing and asthma morbidity and allergic/eosinophilic inflammation, while considering the effect of allergic rhinitis. METHODS: This community-based cohort study, the Nagahama Study, contained a self-reporting questionnaire on mouth breathing and medical history, blood tests, and pulmonary function testing. We enrolled 9804 general citizens of Nagahama City in the Shiga Prefecture, Japan. RESULTS: Mouth breathing was reported by 17% of the population and was independently associated with asthma morbidity. The odds ratio for asthma morbidity was 1.85 (95% CI, 1.27-2.62) and 2.20 (95% CI, 1.72-2.80) in subjects with mouth breathing alone and allergic rhinitis alone, which additively increased to 4.09 (95% CI, 3.01-5.52) when mouth breathing and allergic rhinitis coexisted. Mouth breathing in nonasthmatics was a risk for house dust mite sensitization, higher blood eosinophil counts, and lower pulmonary function after adjusting for allergic rhinitis. CONCLUSION: Mouth breathing may increase asthma morbidity, potentially through increased sensitization to inhaled allergens, which highlights the risk of mouth-bypass breathing in the 'one airway, one disease' concept. The risk of mouth breathing should be well recognized in subjects with allergic rhinitis and in the general population.


Asunto(s)
Asma/epidemiología , Asma/etiología , Respiración por la Boca , Adulto , Anciano , Asma/diagnóstico , Biomarcadores , Estudios de Cohortes , Femenino , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Morbilidad , Oportunidad Relativa , Vigilancia de la Población , Pruebas de Función Respiratoria , Factores de Riesgo , Autoinforme
6.
Allergy ; 69(5): 668-73, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24673601

RESUMEN

BACKGROUND: In steroid-naive patients with asthma, several gene variants are associated with a short-term response to inhaled corticosteroid (ICS) treatment; this has mostly been observed in Caucasians. However, not many studies have been conducted for other ethnicities. Here, we aimed to determine the relationship between the annual decline in forced expiratory flow volume in one second (FEV1 ) and the variant of the glucocorticoid-induced transcript 1 gene (GLCCI1) in Japanese patients with asthma receiving long-term ICS treatment, taking into account the effect of high serum periostin levels, a known association factor of pulmonary function decline and a marker of refractory eosinophilic/Th2 inflammation. METHODS: In this study, 224 patients with asthma receiving ICS treatment for at least 4 years were enrolled. The effects of single-nucleotide polymorphisms (SNPs) in GLCCI1, stress-induced phosphoprotein 1 (STIP1), and T gene on the decline in FEV1 of 30 ml/year or greater were determined. RESULTS: Besides the known contributing factors, that is, the most intensive treatment step, ex-smoking, and high serum periostin levels (≥95 ng/ml), the GG genotype of GLCCI1 rs37973, and not other SNPs, was independently associated with a decline in FEV1 of 30 ml/year or greater. When patients were stratified according to their serum periostin levels, the GG genotype of rs37973 was significantly associated with blood eosinophilia (≥250/µl) in the high serum periostin group. CONCLUSIONS: A GLCCI1 variant is a risk factor of pulmonary function decline in Japanese patients with asthma receiving long-term ICS treatment. Thus, GLCCI1 may be associated with response to ICS across ethnicities.


Asunto(s)
Asma/genética , Asma/fisiopatología , Variación Genética , Receptores de Glucocorticoides/genética , Administración por Inhalación , Corticoesteroides/administración & dosificación , Corticoesteroides/uso terapéutico , Anciano , Asma/tratamiento farmacológico , Asma/inmunología , Moléculas de Adhesión Celular/sangre , Eosinófilos/inmunología , Femenino , Volumen Espiratorio Forzado , Estudios de Asociación Genética , Proteínas de Choque Térmico/genética , Humanos , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Pruebas de Función Respiratoria , Factores de Riesgo
7.
Clin Exp Allergy ; 43(6): 608-15, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23711122

RESUMEN

BACKGROUND: Epidemiological studies have shown that smoking increases the propensity for atopy and asthma. However, the effects of smoking on atopy and eosinophilic inflammation in asthmatics, including the elderly, remain unknown. OBJECTIVE: To determine the effects of smoking on serum immunoglobulin E (IgE) levels and eosinophilic inflammation in asthmatics of all ages. METHODS: The associations of serum IgE levels, blood eosinophil counts and fractional exhaled nitric oxide (FeNO) levels with smoking and age in steroid-naive asthmatics were cross-sectionally assessed (n = 307). Levels of sputum eosinophil and thymic stromal lymphopoietin (TSLP) that promotes Th2 inflammation were also analysed. Current smokers were excluded when analysing contributing factors of FeNO. RESULTS: Levels of serum IgE, blood eosinophil and FeNO decreased with increasing age in never-smokers, whereas decrease in serum IgE levels with increasing age was not observed in current smokers. In addition, current smoking was associated with higher blood eosinophil counts. In atopic asthmatics, age-related declines in serum IgE levels were less steep in ex-smokers than in never-smokers, and atopic ex-smokers with asthma showed higher blood eosinophil counts and higher FeNO irrespective of age. Lastly, sputum TSLP levels were associated with sputum eosinophil proportions and pack-years. Current and ex-smokers had higher TSLP levels than never-smokers. CONCLUSIONS AND CLINICAL RELEVANCE: In steroid-naive asthmatics, smoking may attenuate the age-related decrease in IgE levels and maintain eosinophilic inflammation, in which TSLP may be involved.


Asunto(s)
Eosinófilos/inmunología , Inmunoglobulina E/inmunología , Inflamación/inmunología , Fumar , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Asma/inmunología , Asma/metabolismo , Estudios Transversales , Citocinas/metabolismo , Espiración , Femenino , Compuestos Férricos/sangre , Humanos , Inmunoglobulina E/sangre , Inflamación/sangre , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Nitratos/sangre , Óxido Nítrico , Esputo/metabolismo , Adulto Joven , Linfopoyetina del Estroma Tímico
8.
Artículo en Inglés | MEDLINE | ID: mdl-21462801

RESUMEN

BACKGROUND: Effects of long-term treatment with inhaled corticosteroids (ICSs) on airway-wall thickness in patients with asthma remain unknown. OBJECTIVES: To determine whether airway-wall thickness consistently decreases after long-term ICS treatment, and to analyze factors contributing to long-term airway-wall changes in asthmatics. METHODS: A retrospective analysis of long-term changes in airway-wall thickness using computed tomography was performed in 14 patients with asthma. Wall area corrected by body surface area (WA/BSA) was examined at baseline, 12 weeks after the commencement of ICSs (second measurement), and at least 2 years (mean +/- SEM. 4.2 +/- 0.5) after the second measurement (third measurement). Mean +/- SEM changes in WA/BSA from the second to the third measurements were analyzed. RESULTS: The mean change in WA/BSA was not significant between the second and the third measurements (-0.27 +/- 0.59 mm2/m2/y). Overall, the changes were significantly associated with disease duration but not with other clinical indices. When the 14 patients were divided into 2 groups using a cutoff value of 0.32 mm2/m2/y for the mean change in WA/BSA, for the 5 patients whose WA/BSA exceeded this cutoff, daily ICS doses were not reduced and both forced expiratory volume in the first second (FEV1) and forced vital capacity decreased significantly. For the remaining 9 patients, daily ICS doses were reduced and long-term FEV1 values did not change. CONCLUSIONS: Despite long-term treatment with ICSs, airway-wall thickness did not consistently decrease. One possible mechanism underlying poor response to long-term treatment may be long-standing asthma.


Asunto(s)
Corticoesteroides/efectos adversos , Asma/diagnóstico por imagen , Sistema Respiratorio/patología , Tomografía Computarizada por Rayos X , Administración por Inhalación , Corticoesteroides/uso terapéutico , Adulto , Anciano , Asma/tratamiento farmacológico , Femenino , Humanos , Cuidados a Largo Plazo , Masculino , Persona de Mediana Edad , Sistema Respiratorio/efectos de los fármacos , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
9.
Clin Exp Allergy ; 39(2): 236-45, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19134015

RESUMEN

BACKGROUND: Isoprostanes are prostaglandin (PG)-like compounds synthesized by oxidative stress, not by cyclooxygenase, and increase in bronchoalveolar lavage fluid of patients with asthma. The airway inflammation implicated in this disease may be amplified by oxidants. Although isoprostanes are useful biomarkers for oxidative stress, the action of these agents on airways has not been fully elucidated. OBJECTIVE: This study was designed to determine the intracellular mechanisms underlying the effects of oxidative stress on airway smooth muscle, focused on Ca(2+) signalling pathways involved in the effect of 8-iso-PGF(2 alpha). METHODS: Using simultaneous recording of isometric tension and F(340)/F(380) (an indicator of intracellular concentrations of Ca(2+), [Ca(2+)]i, we examined the correlation between tension and [Ca(2+)]i in response to 8-iso-PGF(2 alpha) in the fura-2 loaded tracheal smooth muscle. RESULTS: Augmented tension and F(340)/F(380) by 8-iso-PGF(2 alpha) were attenuated by ICI-192605, an antagonist of thromboxane A(2) receptors (TP receptors). Moreover, D609, an antagonist of phosphatidylcholine-specific phospholipase C, markedly reduced both the tension and F(340)/F(380) induced by 8-iso-PGF(2 alpha), whereas U73122, an antagonist of phosphatidylinositol-specific phospholipase C, modestly inhibited them by 8-iso-PGF(2 alpha). SKF96365, a non-selective antagonist of Ca(2+) channels, markedly reduced both tension and F(340)/F(380) by 8-iso-PGF(2 alpha). However, diltiazem and verapamil, voltage-dependent Ca(2+) channel inhibitors, modestly attenuated tension although their reduction of F(340)/F(380) was not different from that by SKF96365. Y-27632, an inhibitor of Rho-kinase, significantly attenuated contraction induced by 8-iso-PGF(2 alpha) without reducing F(340)/F(380), whereas GF109203X and Go6983, protein kinase C inhibitors, did not markedly antagonize them although reducing F(340)/F(380) with a potency similar to Y-27632. CONCLUSION: 8-iso-PGF(2 alpha) causes airway smooth muscle contraction via activation of TP receptors. Ca(2+) mobilization by SKF96365- and D609-sensitive Ca(2+) influx and Ca(2+) sensitization by Rho-kinase contribute to the intracellular mechanisms underlying the action of 8-iso-PGF(2 alpha). Rho-kinase may be a therapeutic target for the physiologic abnormalities induced by oxidative stress in airways.


Asunto(s)
Señalización del Calcio/fisiología , Dinoprost/análogos & derivados , Músculo Liso/efectos de los fármacos , Tráquea/efectos de los fármacos , Tráquea/fisiología , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacología , Amidas/farmacología , Animales , Hidrocarburos Aromáticos con Puentes/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Señalización del Calcio/efectos de los fármacos , Diltiazem/farmacología , Dinoprost/farmacología , Dioxanos/farmacología , Inhibidores Enzimáticos/farmacología , Estrenos/farmacología , Cobayas , Imidazoles/farmacología , Técnicas In Vitro , Indoles/farmacología , Masculino , Maleimidas/farmacología , Contracción Muscular/efectos de los fármacos , Contracción Muscular/fisiología , Músculo Liso/fisiología , Norbornanos , Piridinas/farmacología , Pirrolidinonas/farmacología , Receptores de Tromboxano A2 y Prostaglandina H2/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Tiocarbamatos , Tionas/farmacología , Fosfolipasas de Tipo C/antagonistas & inhibidores , Vasoconstrictores/farmacología , Verapamilo/farmacología , Quinasas Asociadas a rho/antagonistas & inhibidores
10.
Artículo en Inglés | MEDLINE | ID: mdl-18564632

RESUMEN

BACKGROUND: Transforming growth factor (TGF) beta1 is considered to play central roles in the pathogenesis of airway remodeling in asthma. This notion is based primarily on the results of experimental studies; clinical evidence is limited. OBJECTIVES: To ascertain the involvement of TGF-beta1 in asthma. METHODS: We studied 27 patients with moderate-to-severe, but stable, asthma treated with inhaled corticosteroids and 8 healthy controls. Helical computed tomography scans were acquired at full inspiration. Airway wall thickness (WT) was assessed on the basis of wall area corrected for body surface area (WA/BSA) and absolute WT corrected for BSA (WT/square root of BSA) according to a validated method. Induced sputum concentrations of TGF-beta1 were measured by enzyme-linked immunosorbent assay. Pulmonary function was evaluated. RESULTS: Indices of expiratory airflow were significantly lower in the asthmatic patients than in the controls. WA/BSA, WT/square root of square root of BSA, and sputum concentrations of TGF-beta1 were significantly higher in the asthmatic patients. Sputum TGF-beta1 concentrations correlated positively with WA/BSA and WT/square root of BSA and negatively with forced expiratory volume in 1 second in both asthmatic and control subjects. CONCLUSIONS: Levels of TGF-beta1 in induced sputum are elevated in asthmatic patients despite treatment with inhaled corticosteroids and are associated with airflow obstruction and airway wall thickening. TGF-beta1 is involved in the pathogenesis of airway remodeling and resultant functional impairment and it may be a target for specific medical treatment.


Asunto(s)
Corticoesteroides/uso terapéutico , Asma/metabolismo , Esputo/química , Factor de Crecimiento Transformador beta1/análisis , Adulto , Anciano , Antiasmáticos/uso terapéutico , Asma/diagnóstico por imagen , Asma/tratamiento farmacológico , Asma/patología , Femenino , Volumen Espiratorio Forzado , Humanos , Pulmón/diagnóstico por imagen , Pulmón/patología , Masculino , Persona de Mediana Edad , Tomografía Computarizada Espiral
11.
Clin Exp Allergy ; 38(1): 135-44, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18028457

RESUMEN

BACKGROUND: Recent studies have revealed that in asthma, mast cells infiltrate to the smooth muscle layer and release tryptase, an enzymatic activator of protease-activated receptor 2 (PAR2). This phenomenon, mast cell myositis, is proposed as a new feature of asthma. However, little is known about the involvement of mast cell myositis in the pathophysiology of asthma. OBJECTIVE: This study was designed to determine whether mast cell degranulation has any functional impact on beta-adrenoceptors via PAR2 in airway smooth muscle. Moreover, we focused on Ca(2+) signalling as a mechanism underlying alteration of smooth muscle tone and responsiveness. METHODS: Isometric tension and F(340)/F(380), an indicator of the concentration of intracellular Ca(2+) ([Ca(2+)](i)), were simultaneously measured using fura-2-loaded tissues isolated from guinea-pig tracheal smooth muscle. RESULTS: Tryptase (1-100 nm) caused tension with elevated F(340)/F(380), and after exposure to tryptase for 15 min the inhibitory effect of isoprenaline (ISO) against methacholine was attenuated without elevating F(340)/F(380) in a concentration-dependent manner. Tryptase (<1 nm) had a modest effect on tension, but prolonged treatment (

Asunto(s)
Calcio/metabolismo , Mastocitos/enzimología , Músculo Liso/metabolismo , Receptores Adrenérgicos beta/metabolismo , Tráquea/metabolismo , Triptasas/metabolismo , Agonistas Adrenérgicos beta/farmacología , Animales , Señalización del Calcio/efectos de los fármacos , Cobayas , Humanos , Masculino , Mastocitos/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Receptor PAR-2/metabolismo , Tráquea/efectos de los fármacos , Quinasas Asociadas a rho/metabolismo
12.
Clin Exp Allergy ; 37(6): 893-900, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17517103

RESUMEN

BACKGROUND: The release of adenosine triphosphate (ATP) from the airway epithelial cells during the inflammatory process is considered to play an important role in the pathophysiology of asthma and chronic obstructive pulmonary disease. OBJECTIVE: This study was designed to determine whether extracellular ATP is involved in the bronchial hyperresponsiveness as an interaction between epithelium and smooth muscle in the airways. METHODS: We examined the contractile response to methacholine (MCh) before and after exposure to low concentrations (< or = 10 microm) of ATP in isolated, epithelium-denuded guinea-pig tracheal smooth muscle by measuring isometric tension. Intracellular Ca2+ concentrations ([Ca2+]i) were assessed by fluorescent intensities of fura-2. RESULTS: MCh-induced contractile force was increased with no change in [Ca2+]i after exposure to 10 microm ATP for 15 min. The ability of ATP to enhance the MCh-induced contraction was markedly attenuated by suramin, a non-selective P2 receptor inhibitor. Pre-incubation with ATPgammaS, a non-hydrolysable analogue of ATP and alpha,beta-meATP, a P2X agonist, also enhanced the MCh-induced contraction. In contrast, uracil triphosphate, a P2Y agonist, did not affect the MCh-induced contraction. Y-27632, a Rho-kinase inhibitor, suppressed the ability of ATP to enhance the MCh-induced contraction. Moreover, PP1 and PP2, Src tyrosin kinase inhibitors, suppressed the enhancement of MCh-induced contraction by ATP. CONCLUSION: Pre-treatment with ATP induces hyperresponsiveness to MCh mediated by Ca2+ sensitization via the P2X receptor in airway smooth muscle. The present findings suggest the possible involvement of both the Rho-kinase and Src pathways in the intracellular mechanism of this phenomenon.


Asunto(s)
Adenosina Trifosfato/farmacología , Bronquios/metabolismo , Hiperreactividad Bronquial/metabolismo , Señalización del Calcio , Miocitos del Músculo Liso/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Agonistas del Receptor Purinérgico P2 , Mucosa Respiratoria/metabolismo , Adenosina Trifosfato/agonistas , Adenosina Trifosfato/análogos & derivados , Adenosina Trifosfato/inmunología , Adenosina Trifosfato/metabolismo , Amidas/farmacología , Animales , Bronquios/inmunología , Bronquios/patología , Hiperreactividad Bronquial/inmunología , Hiperreactividad Bronquial/patología , Broncoconstrictores/agonistas , Broncoconstrictores/farmacología , Calcio/inmunología , Calcio/metabolismo , Señalización del Calcio/inmunología , Células Cultivadas , Sinergismo Farmacológico , Inhibidores Enzimáticos/farmacología , Cobayas , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular/inmunología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Contracción Isométrica/efectos de los fármacos , Contracción Isométrica/inmunología , Masculino , Cloruro de Metacolina/agonistas , Cloruro de Metacolina/farmacología , Miocitos del Músculo Liso/inmunología , Miocitos del Músculo Liso/patología , Técnicas de Cultivo de Órganos , Fosfoproteínas Fosfatasas/antagonistas & inhibidores , Fosfoproteínas Fosfatasas/inmunología , Fosfoproteínas Fosfatasas/metabolismo , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/inmunología , Proteínas Serina-Treonina Quinasas/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/inmunología , Enfermedad Pulmonar Obstructiva Crónica/patología , Piridinas/farmacología , Receptores Purinérgicos P2/inmunología , Receptores Purinérgicos P2/metabolismo , Receptores Purinérgicos P2X , Mucosa Respiratoria/inmunología , Mucosa Respiratoria/patología , Factores de Tiempo , Quinasas Asociadas a rho , Familia-src Quinasas/antagonistas & inhibidores , Familia-src Quinasas/inmunología , Familia-src Quinasas/metabolismo
13.
Clin Exp Allergy ; 36(2): 183-91, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16433855

RESUMEN

BACKGROUND: It is well known that beta-adrenoceptor agonists (beta-agonists) cause relaxation in airway smooth muscle mediated by a reduction in the concentration of intracellular Ca2+ ([Ca2+](i)). However, little is currently known regarding whether reduced sensitization to Ca2+ is involved in the beta-adrenergic relaxation. OBJECTIVE: This study was designed to determine the intracellular mechanisms underlying suppression of Ca2+ sensitization in beta-adrenergic relaxation (Ca(2+)-independent relaxation by beta-agonists). Methods Isometric tension and [Ca2+](i) were simultaneously measured in fura-2-loaded strips isolated from guinea-pig tracheal smooth muscles. The relationships between tension and [Ca2+](i) were examined in the inhibitory action of isoprenaline (ISO) and other cAMP-related agents against methacholine-induced contraction. RESULTS: The concentration-inhibition curve for ISO against methacholine in tension was significantly dissociated from the curve for ISO in [Ca2+](i). In ISO-induced relaxation, a reduction in tension was significantly greater than that in [Ca2+](i.) This phenomenon was mimicked by other cAMP-related agents: forskolin and dibutyryl-cAMP. In contrast, the inhibitory action of SKF-96365, a non-selective inhibitor of Ca(2+) channels, was associated with that in [Ca2+](i). In the presence of Rp-cAMPS, an inhibitor of protein kinase A (PKA), ISO caused an equivalent relaxation with less reduction in [Ca2+](i). The effects of ISO were not affected by Y-27632, an inhibitor of Rho-kinase, or by bisindolylmaleimide, an inhibitor of protein kinase C. ISO failed to inhibit contraction elicited by calyculin A, an inhibitor of myosin phosphatase. Conclusion beta-Adrenergic action antagonizes not only Ca2+ mobilization but also Ca2+ sensitization in methacholine-induced contraction. The cAMP/PKA-independent, G(s)-direct action is more potent in Ca(2+)-independent relaxation by beta-agonists than the cAMP/PKA-dependent pathway. Moreover, myosin phosphatase is a fundamentally affected protein in the reduced response to Ca2+ mediated by beta-agonist. Our results may provide evidence that this Ca2+ desensitization is a novel target for a reliever medication using rapid-acting beta-agonists in acute asthma management.


Asunto(s)
Agonistas Adrenérgicos beta/farmacología , Calcio/metabolismo , Isoproterenol/farmacología , Músculo Liso/efectos de los fármacos , Amidas/farmacología , Animales , Asma/tratamiento farmacológico , Bucladesina/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Colforsina/farmacología , Proteína Receptora de AMP Cíclico/farmacología , Proteínas Quinasas Dependientes de AMP Cíclico/antagonistas & inhibidores , Depresión Química , Fura-2 , Cobayas , Imidazoles/farmacología , Técnicas In Vitro , Indoles/farmacología , Péptidos y Proteínas de Señalización Intracelular , Masculino , Maleimidas/farmacología , Toxinas Marinas , Cloruro de Metacolina/farmacología , Contracción Muscular/efectos de los fármacos , Músculo Liso/metabolismo , Fosfatasa de Miosina de Cadena Ligera/antagonistas & inhibidores , Oxazoles/farmacología , Proteína Quinasa C/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Piridinas/farmacología , Tráquea , Quinasas Asociadas a rho
14.
Ann Oncol ; 15(4): 671-9, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15033678

RESUMEN

BACKGROUND: TZT-1027 is a synthetic dolastatin 10 analog with antineoplastic properties in various cell lines and tumor xenografts. The purpose of this phase I study was to evaluate the safety and toxicity, maximum tolerated dose, pharmacokinetics and pharmacodynamics, clinical and metabolic antitumor activity of TZT-1027 when given as a 1-h intravenous infusion every 3 weeks in patients with refractory solid tumors. PATIENTS AND METHODS: Patients had a histologically verified refractory tumor with measurable disease, were > or = 18 years old, had an Eastern Cooperative Oncology Group performance status <2 and adequate bone marrow, liver, renal and cardiac function. Dose-limiting toxicity was defined as platelets <25 x 10(9)/l, neutrophils <0.5 x 10(9)/l for >5 days, febrile neutropenia > or = 38.5 degrees C with grade 4 (National Cancer Institute-common toxicity criteria) neutropenia, or grade 3/4 non-hematological toxicity excluding nausea and vomiting. The last dose was the dose where > or = 2 out of six patients experienced dose-limiting toxicity in cycle one. The maximum tolerated dose was one dose level below with less than two of six patients with dose-limiting events. RESULTS: Twenty-one non-selected, fully evaluable patients were enrolled. The majority were male (19) and the median age was 55 years (range 39-67). Dose levels of TZT-1027 ranged from 1.35 to 3.0 mg/m(2). The median number of cycles was two (range 1-4). Dose-limiting toxicities were observed in three patients at the 3.0 mg/m(2) dose level, including neutropenia, fatigue and a short lasting, reversible peripheral neurotoxic syndrome. The most common toxicities per patient were fatigue, anorexia, alopecia, nausea, constipation, leukopenia and neutropenia. Based on RECIST criteria, the best response was stable disease in seven patients. The pharmacokinetic evaluation revealed a T(1/2) of approximately 7 h and linear kinetics. CONCLUSIONS: The recommended dose of TZT-1027 for the 3-weekly administration is 2.7 mg/m(2). Neutropenia, fatigue and a reversible peripheral neurotoxic syndrome are dose-limiting with this schedule. TZT-1027 may be associated with neurological side-effects in patients previously exposed to neurotoxic compounds such as oxaliplatin.


Asunto(s)
Antineoplásicos/farmacocinética , Neoplasias/tratamiento farmacológico , Oligopéptidos/farmacocinética , Adulto , Anciano , Alopecia/inducido químicamente , Anorexia/inducido químicamente , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Área Bajo la Curva , Estreñimiento/inducido químicamente , Depsipéptidos , Relación Dosis-Respuesta a Droga , Fatiga/inducido químicamente , Femenino , Humanos , Infusiones Intravenosas , Leucopenia/inducido químicamente , Masculino , Persona de Mediana Edad , Náusea/inducido químicamente , Neoplasias/metabolismo , Neutropenia/inducido químicamente , Oligopéptidos/efectos adversos , Oligopéptidos/síntesis química , Oligopéptidos/química , Oligopéptidos/uso terapéutico
15.
Cancer Chemother Pharmacol ; 50(3): 230-6, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12203105

RESUMEN

PURPOSE: To predict the optimal dosage for nedaplatin ( cis-diammineglycolatoplatinum), an anticancer drug and a platinum derivative like cisplatin and carboplatin, a simple formula was developed based on renal function in Japanese adult cancer patients. PATIENTS AND METHODS: Unbound platinum concentrations in plasma after intravenous infusion of nedaplatin were measured for 187 courses in 145 patients with lung, esophageal, and cervical and ovarian cancer undergoing clinical treatment. The data were divided into two sets, a model development data set of 94 courses and a validation data set of 93 courses. Regression analysis was applied to the relationship between the unbound platinum clearance (CL) of nedaplatin and the patients' renal function. The predictability and usefulness of this formula were assessed by validation using the external data set of 93 courses obtained from 75 patients. RESULTS: A simple formula was obtained for predicting the platinum clearance using the creatinine clearance (CLcr): CL=0.0836xCLcr+3.45. Indices for the predictive performance for CL and the area under the plasma concentration curve (AUC) in the validation data were almost the same as those for the model development data. CONCLUSIONS: A formula for predicting the CL of unbound platinum after nedaplatin administration was developed, and only CLcr was found to be a significant covariate of the CL. This formula was useful for estimating the CL for the second as well as the first treatment with nedaplatin.


Asunto(s)
Antineoplásicos/administración & dosificación , Riñón/fisiología , Modelos Teóricos , Compuestos Organoplatinos/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/farmacocinética , Área Bajo la Curva , Relación Dosis-Respuesta a Droga , Femenino , Predicción , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Compuestos Organoplatinos/farmacocinética , Análisis de Regresión
17.
Horm Metab Res ; 34(1): 27-31, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11832998

RESUMEN

The aim of the present study was to investigate the effects of short-term physical exercise that did not change body mass on insulin sensitivity, insulin secretion, and glucose and lipid metabolism in 39 non-obese Japanese type 2 diabetic patients. Insulin sensitivity and insulin secretion were estimated with homeostasis model assessment insulin resistance (HOMA-IR) and HOMA-B-cell function proposed by Matthews et al., respectively. All patients were hospitalized and were engaged in low-intensity exercise that consisted of walking and dumbbell exercise for successive 7 days. There were no changes in hospital diet and the dose of any medications used throughout the study. Fasting glucose, insulin, and lipids were measured before and after exercise. After exercise, serum triglyceride levels significantly decreased, but no significant changes were observed in total and HDL cholesterol concentrations. Fasting glucose, insulin, and HOMA-IR levels significantly decreased after exercise, but HOMA-B-cell function did not change during the study. There was no significant difference between BMI levels before and after exercise. From these results, it can be concluded that short-term (7 days) low-intensity physical exercise combined with hospital diet reduces serum triglycerides, insulin resistance, and fasting glucose levels without affecting BMI in non-obese Japanese type 2 diabetic patients.


Asunto(s)
Diabetes Mellitus Tipo 2/fisiopatología , Ejercicio Físico/fisiología , Glucosa/metabolismo , Resistencia a la Insulina/fisiología , Insulina/metabolismo , Metabolismo de los Lípidos , Adulto , Anciano , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/metabolismo , Femenino , Homeostasis/fisiología , Humanos , Insulina/sangre , Insulina/fisiología , Secreción de Insulina , Japón , Lípidos/sangre , Masculino , Persona de Mediana Edad , Triglicéridos/sangre
18.
Clin Cancer Res ; 7(10): 3056-64, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11595695

RESUMEN

PURPOSE: A Phase I study of exatecan, a new water-soluble camptothecin derivative, was conducted to determine the maximum tolerated dose and a recommended dose, according to an internationally standardized core protocol. Pharmacological profiles of lactone and total (lactone + carboxylate) exatecan were also investigated. PATIENTS AND METHODS: Fifteen patients with advanced solid malignancies were treated with 3, 5, and 6.65 mg/m(2) of exatecan infused over 30 min every 3 weeks. Concentrations of lactone, total drug, and a metabolite in plasma and urine were determined during the first course. RESULTS: Dose-limiting neutropenia and liver dysfunction were observed in two of six patients at 6.65 mg/m(2), but no grade 3 or worse diarrhea was observed. Emesis was moderate, and no grade 3 or worse nausea and vomiting were observed at a recommended dose of 5 mg/m(2), with prophylactic use of granisetron. Pharmacokinetics were linear and had moderate variability; clearances of lactone and total drug were 6.8 +/- 2.8 and 2.1 +/- 1.1 (mean +/- SD) l/h/m(2), respectively. The ratio of lactone concentration to total drug concentration in plasma decreased from 0.81 +/- 0.06 at the end of infusion to 0.15 +/- 0.06 10 h after the infusion. The lactone:total ratio of drug exposure was 0.30 +/- 0.08, ranging from 0.16 to 0.43. Neutropenia was related to the drug exposure of both lactone and total drug. CONCLUSIONS: The recommended dose of exatecan infused over 30 min every 3 weeks is 5 mg/m(2), with a favorable toxicity profile of mild and infrequent diarrhea. Interpatient variability of pharmacokinetics was similar to or smaller than that with other camptothecin derivatives.


Asunto(s)
Antineoplásicos Fitogénicos/uso terapéutico , Camptotecina/uso terapéutico , Neoplasias/tratamiento farmacológico , Adulto , Anciano , Anemia/inducido químicamente , Antineoplásicos Fitogénicos/efectos adversos , Antineoplásicos Fitogénicos/farmacocinética , Área Bajo la Curva , Camptotecina/análogos & derivados , Camptotecina/farmacocinética , Diarrea/inducido químicamente , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Náusea/inducido químicamente , Neutropenia/inducido químicamente , Trombocitopenia/inducido químicamente , Factores de Tiempo , Resultado del Tratamiento , Vómitos/inducido químicamente
20.
Biomed Chromatogr ; 15(5): 356-62, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11507718

RESUMEN

We established a highly sensitive quantitative analytical method for chondroitin/dermatan sulfates by LC/MS method. By this method, the unsaturated disaccharides produced after the enzymatic digestion of chondroitin/dermatan sulfates can be determined in the amounts as low as 0.5 pmol levels. The use of tetrabutylammonium hydroxide as an ion-pair reagent for LC/MS allowed us to separate unsaturated 4-sulfated disaccharide and unsaturated 6-sulfated disaccharide. Furthermore, the peak areas of unsaturated disaccharides were increased almost 10 times by the postcolumn addition of acetonitrile. We applied this LC/MS method to the analyses of unsaturated disaccharides from chondroitin/dermatan sulfates in the tissues sections on glass slides, which were prepared from MethA tumor-bearing mice. This method brought about considerable reduction in the time distance from sample collection to preparation of analytical results.


Asunto(s)
Sulfatos de Condroitina/análisis , Cromatografía Líquida de Alta Presión/métodos , Dermatán Sulfato/análisis , Espectrometría de Masas/métodos , Neoplasias/química , Neoplasias/patología , Reproducibilidad de los Resultados
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