ABSTRACT
Este estudo buscou investigar o papel do estresse oxidativo e nitrosativo no enfisema pulmonar induzido por elastase. Foram utilizados camundongos machos C57BL/6 submetidos a dois modelos de indução do enfisema por elastase pancreática suína (PPE): intratraqueal (i.t.) e intranasal (i.n.). No modelo intratraqueal a PPE foi instilada nas doses de 0,05 U ou 0,05 U/camundongo para avaliação temporal do enfisema 7, 14 e 21 dias após instilação de PPE. Em outra etapa, o papel da iNOS foi avaliado através da sua inibição farmacológica por aminoguanidina (AMG) 1% na água de beber ou pela sua exclusão genética em camundongos deficientes em iNOS que tiveram o enfisema induzido por 0,5 U PPE i.t. após 21 dias. No modelo intranasal a dose de PPE foi 3 U/camundongo para avaliação temporal do enfisema (1, 7, 14 e 21 dias após PPE). O papel do estresse oxidativo e nitrosativo foi avaliado com diferentes tratamentos antioxidantes na água de beber: tempol, apocinina+alopurinol, n-acetilcisteína, vitamina C+E, e aminoguanidina durante os 21 dias de indução do enfisema. Os grupos controles foram submetidos à instilação de salina. Lavado broncoalveolar, imunoensaios, análises bioquímicas de estresse oxidativo e ensaios morfométricos foram realizados nos pulmões dos animais. O enfisema foi histologicamente alcançado em 21 dias após 0,5 U PPE i.t., evidenciado pelo aumento do diâmetro alveolar médio - Lm e da densidade de volume dos espaços alveolares - Vvair em comparação ao grupo controle. TNF-a foi aumentado em 7 e 14 dias após 0,05 U PPE comparados ao controle, concomitante com a redução de IL-10 nos mesmos períodos, comparados ao controle. O estresse oxidativo foi observado na fase inicial do enfisema, com aumento dos níveis de nitrito, TBARS e superóxido dismutase no grupo 7 dias após 0,5 U PPE (i.t.) quando comparados ao controle ao passo que no modelo intranasal as alterações típicas do estresse foram vistas no grupo 1 dia após 3 U de PPE. Atividade da glutationa ...
This study investigated the role of oxidative and nitrosative stress in elastase-induced pulmonary emphysema. C57BL/6 male mice were used submitted to two models of emphysema induced by porcine pancreatic elastase (PPE): intratracheal (i.t.) and intranasal (i.n.). In the intratracheal model PPE was instilled at doses of 0.05 U or 0.5 U/mouse (i.t.) to temporal evaluation of emphysema 7, 14 and 21 days post-PPE instillation. Others sets of experiments, the role of iNOS was evaluated through its pharmacology inhibition by 1% aminoguanidine (AMG) into the drinking water or bt iNOS genetic exclusion in iNOS-deficient mice which had induced emphysema by 0.5 U PPE i.t. after 21 days. In the intranasal model the PPE dose was 3 U/mouse to temporal evaluation of emphysema (1, 7, 14 and 21 days after PPE). The role of oxidative and nitrosative stress was evaluated using different antioxidant treatments into the drinking water: tempol, apocynin+allopurinol, N-acetylcysteine, vitamin C+E and aminoguanidine during the 21 days of emphysema induction. Control groups were instilled with saline. Bronchoalveolar lavage, immunoassays, biochemical analysis of oxidative stress and morphometric tests were performed in the lungs of animals. The emphysema was histologically reached 21 days after 0.5 U PPE, as evidenced by an increase in alveolar diameter - Lm and volume density of the alveolar spaces - Vvair compared to the control group. TNF-a was increased in 7 and 14 days after 0.5 U PPE compared to the control, concomitant with reduction of IL-10 at the same time-points compared to the control. Oxidative stress was observed in the early stages of emphysema, with increased levels of nitrite, TBARS and superoxide dismutase in group 7 days after 0.5 U PPE (i.t.) compared to the control, while in the intranasal model the typical stress alterations were seen in group 1 day after 3 U PPE. Glutathione peroxidase activity was increased in all PPE groups (i.t.). Exposure to 0.5 U PPE ...
Subject(s)
Animals , Mice , Pulmonary Disease, Chronic Obstructive/chemically induced , Pulmonary Disease, Chronic Obstructive/metabolism , Pancreatic Elastase/administration & dosage , Pancreatic Elastase/metabolism , Pulmonary Emphysema/chemically induced , Pulmonary Emphysema/metabolism , Antioxidants/pharmacology , Oxidative Stress/physiology , Inflammation , Nitric Oxide Synthase/biosynthesis , Nitric Oxide Synthase/metabolism , Lung/pathologyABSTRACT
Introduction: Intratracheal instillation of elastase induces diffuse alveolar damage and emphysema development. However, the Syrian Golden hamster develops more severe emphysema than the Sprague-Dawley rat. Although it is known that early events after elastase instillation determine the magnitude of emphysema development, it is not known if there are species differences in the initial pattern of lung response to elastase. Objective: To evaluate whether rats and hamster differ in the early lung response to elastase, using biochemical markers of acute lung injury. Results: Whereas the rat shows a large increase in alveolar-capillary permeability and few hemorrhagic changes, the hamster shows significant amount of hemorrhage and a small increase in alveolar capillary permeability. Conclusions: There are differences between rats and hamsters in the initial lung response to elastase that could influence the magnitude of emphysema development.
Introducción: El modelo de instilación intratraqueal de elastasa induce daño alveolar difuso y destrucción de la matriz extracelular con desarrollo de enfisema. Sin embargo, el hámster Syrian Golden desarrolla enfisema más severo que el de la rata Sprague-Dawley. Si bien se sabe que los eventos tempranos después de la instilación de elastasa determinan la magnitud del enfisema, se desconoce si existen diferencias entre especies en la respuesta pulmonar temprana. Objetivo: Evaluar si existen diferencias entre ratas y hamsters en la respuesta pulmonar inicial después de la elastasa, mediante el uso de marcadores bioquímicos de daño pulmonar agudo. Resultados: Mientras la rata experimenta un gran aumento de permeabilidad alvéolo-capilar y pocos fenómenos hemorrágicos, el hamster presenta abundante hemorragia y escaso aumento de la permeabilidad. Conclusiones: Existen diferencias entre ratas y hamsters en la respuesta pulmonar inicial frente a la elastasa, que podrían tener relación con las diferencias en magnitud del enfisema.
Subject(s)
Animals , Male , Rats , Pancreatic Elastase/administration & dosage , Emphysema/chemically induced , Bronchoalveolar Lavage , Disease Models, Animal , Dose-Response Relationship, Drug , Pancreatic Elastase/metabolism , Emphysema/enzymology , Hemorrhage/chemically induced , Mesocricetus , Biomarkers , Capillary Permeability , Lung , Lung/enzymology , Rats, Sprague-DawleyABSTRACT
In order to study the colonic intraluminal proteinase-antiproteinase imbalance under inflammatory conditions, we determined proteolytic activity (PA), alpha-1-antitrypsin and the activities of trypsin, chymotrypsin and neutrophil elastase in feces from patients with ulcerative colitis (UC) comparing the results with a control group. A fecal sample was obtained from each of 25 patients with ulcerative colitis and 10 control subjects were studied. The severity of the disease was assessed by the Truelove index. Proteolytic activity was measured lesing azocasein as proteolytic substrate. The fecal concentration of alpha-1-antitrypsin was measured by radial immunodiffusion and the activities of the enzymes were measured using specific substrates. We found an increase in fecal PA, alpha-1-antitrypsin and neutrophil elastase in patients with UC and the correlation between the severity of the disease and the PA was statistically significant (r = 0.62, P < 0.05). We conclude that elevated colonic proteinase activity could contribute to the pathophysiology of ulcerative colitis.
Subject(s)
Humans , alpha 1-Antitrypsin/analysis , Colitis, Ulcerative/enzymology , Serine Proteases/metabolism , Chymotrypsin/metabolism , Colitis, Ulcerative/physiopathology , Pancreatic Elastase/metabolism , Statistics, Nonparametric , Trypsin/metabolismABSTRACT
El déficit de alfa-1 antitripsina (a-1 AT), también llamado inhibidor de proteasa, es un defecto genético asociado al desarrollo de enfisema pulmonar precoz y menos frecuentemente a cirrosis hepática. Los fenotipos asociados son PiZZ y PiZNulo, caracterizados por un nivel de a-1 AT plasmático menor de 40 mg/dl. La enfermedad pulmonar se presenta habitualmente antes de los 40 años y su progresón es lenta pero puede ser acelerada marcadamente por el hábito tabáquico. La hipótesis del desbalance elastasa-antielastasa postula que la a-1 AT protege al pulmón del daño elastolítico producido por la elastada del neutrófilo. Su déficit lo dejaría altamente vulnerable a una destrucción progresiva que culmina en el enfisema clínico. Como la terapia de aumentar la producción endógena de a-1 AT o disminuir la elastasa no han tenido éxito, su enfoque actual se ha centrado en aumentar la a-1 AT en forma exógena con infusiones iv mensuales, lo que se está probando en un estudio multicéntrico europeo. La terapia genética se encuentra aún en fase experimental
Subject(s)
Humans , alpha 1-Antitrypsin/deficiency , Pulmonary Emphysema/etiology , alpha 1-Antitrypsin/administration & dosage , alpha 1-Antitrypsin/therapeutic use , Pancreatic Elastase/metabolism , Phenotype , Pulmonary Emphysema/diagnosis , Pulmonary Emphysema/drug therapy , Pulmonary Emphysema/physiopathology , Smoking/adverse effectsABSTRACT
Treinta y cuatro cepas de Aspergillus fumigatus aisladas del aire, crín de caballo, suelo agrícola y del hombre, fueron examinadas con el fin de evaluar la producción de elastasa. Las cepas de Aspergillus fumigatus fueron cultivadas en un medio sólido con elastina, apreciándose en ella su amplio solubilización por la acción del hongo. Los aislamientos fúngicos provenientes de muestras aisladas del hobre y de suelos agrícolas fueron detectados como los más altos productores de elastasa. Ocho de las 34 cepas fueron desarrollas en 4 diferentes medios líquidos en las cuales se investigó la actividad proteolítica total y específica. Los resultados de este experimento sugieren que la producción de elastasa es inducida por la presencia de elastina como sustrato y que la primera es una enzima semejante a la quimiotripsina. El perfil inhibitorio comprobó que la elastina de A.fumigatus, es una serina-proteinasa
Subject(s)
Aspergillus fumigatus/enzymology , Pancreatic Elastase/metabolism , Elastin/metabolism , Chymotrypsinogen/metabolismABSTRACT
Se cuantificó la actividad proteolítica y elastásicaa de 32 cepas de Psudomonas aeruginosa, provenientes de distintas infecciones en humanos. Se diagramaron métodos fotocolirimétricos con sustratos insolubles derivados de polvo de piel unido covalentemente a azul de remazol (HPA) y elatina coloreada con rojo congo (ERC). El 100% de las cepas presentaron actividad proteolítica sobre HPA y el 56,25% resultaron positivas con el sustrato elastina siendo más elevados los valores de unidad enzimática por ml para el primero