Instilación intratraqueal de elastasa en la rata: cambios electroforéticos de la alfa1-AT-antitripsina en el lavado broncoalveolar / Intratracheal instillation of elastase in the rat: electrophoretical changes of alphal-antitrypsin in bronchoalveolar lavage fluid

Introduction: Endogenous alphal-antitrypsin alpha is the main inhibitor of the intratracheally instilled elastase in experimental animals. Objective: To evaluate by electrophoresis and immunodetection using western blot analysis, the different forms of alpha1-AT in bronchoalveolar lavage fluid (BALF) of Sprague Dawley rats after intratracheal instillation of elastase, with the hypothesis that the previously observed increment in antielastase activity is due to high levels of active alpha1-AT. Results: In the first hours after elastase instillation the concentration of alpha1-AT increases more than seven times due to an increase in alveolar-capillary permeability. Alpha 1-AT in BAIF is found as the native protein (~ 52 kDa), as complexes of different molecular sizes (> 75 kDa and > 100 kDa) and as a proteolytic product (< 40 kDa). Conclusion: In spite of a high proportion of alpha1-AT in the inactive form as part of different complexes, the increase in alveolar-capillary permeability after elastase treatment contributes to maintain high levels of active alpha. These results could be of importance in other inflammatory lung processes.

Introducción: la antiproteasa alfa 1-antitripsina alfa constituye el principal inhibidor endógeno de la elastasa instilada por vía intratraqueal en modelos experimentales. Objetivo: Evaluar mediante electroforesis e inmunodetección por western blot, las distintas formas en que se encuentra la alfa1-AT en el lavado broncoalveolar (IBA) de ratas Sprague Dawley después de la instilación de elastasa, con la hipótesis de que el aumento en la actividad antielastasa previamente encontrada se acompaña de niveles altos de alfa1-AT activa. Resultados: En las primeras horas post-elastasa la concentración de alfa1-AT en el IBA aumenta más de 7 veces, debido al aumento de la permeabilidad alvéolo-capilar, encontrándose tanto como proteína nativa (~ 52 kDa), como parte de complejos de mayor tamaño (> 75 kDa y > 100 kDa) y como producto de proteólisis (< 40 kDa). Conclusión: A pesar de existir una alta proporción de alfa1-AT inactiva formando complejos, el aumento de la permeabilidad alvéolo-capilar contribuye a mantener niveles altos de alfa1-AT activa. Estos resultados podrían ser extrapolables a distintos procesos inflamatorios pulmonares.

Degradation of immunoglobulins, protease inhibitors, and interleukin-1 by a secretory proteinase of Acanthamoeba castellanii

The effect of a secretory proteinase from the pathogenic amoebae Acanthamoeba castellanii on hosts defense-oriented or regulatory proteins such as immunoglobulins, interleukin-1, and protease inhibitors was investigated. The enzyme was found to degrade secretory immunoglobulin A (sIgA), IgG, and IgM. It also degraded interleukin-1alpha (IL-1alpha) and IL-1beta. Its activity was not inhibited by endogenous protease inhibitors, such as alpha2-macroglobulin, alpha1-trypsin inhibitor, and alpha2-antiplasmin. Furthermore, the enzyme rapidly degraded those endogenous protease inhibitors as well. The degradation of hosts defense-oriented or regulatory proteins by the Acanthamoeba proteinase suggested that the enzyme might be an important virulence factor in the pathogenesis of Acanthamoeba infection.

Acute myocardial infarction in a 34-year-old HIV-positive female patient while undergoing active antiretroviral therapy containing a protease inhibitor

We describe the case of a young HIV-positive patient undergoing three-drug antiretroviral therapy that included a protease inhibitor for 9 months, who was admitted to the hospital with an acute myocardial infarction. A coronary angiogram revealed occlusion caused by a thrombus in the proximal third of the anterior descending artery. Complete recanalization was obtainedafter an angioplasty was performed. At the time of the infarction, only the triglyceride levels were found to be high. Metabolic alterations associated with the prolonged use of protease inhibitors have been described such as an increase in the triglyceride and the cholesterol serum levels, diabetes, resistence to insulin, lipodystrophy, and pancreatitis. The consequences of chronic hyperlipidemia are well known in the medical literature, especially premature coronary artery disease. No family history of coronary disease was identified in this patient. Whether the genesis of this localized thrombosis was due to a change in the metablism of the vascular endothelium caused by the protease inhibitors, or by related dyslipidemia, is still to be determined. In this case, the data suggest a strong link between coronary insufficiency and prolonged use of the protese inhibitor.

effect of some inducers and inhibitors on protease production by bacillus cereus

Batch cultures of Bacillus cereus grew most luxuriantly with 3% glucose [w/v], 2% tryptone, 0.5% K2HSO4 and 1 mg/ml MnCl2H2O, supplemented to the basal medium with high enzyme activity [biomass 3.06 g/100 ml and enzyme activity 57.19 U/ml, with specific activity 39.44 U/mg protein]. All the tested nitrogen sources, ascorbic acid, ATP, chloramphenicol and vitamins exerted a significant decrease in the enzyme production

Proteinase-inhibitor activity in sera of patients with carcinoma of the cervix uteri

Se ha demostrado claramente la participación de las proteinasas neoplásicas en la progresión de los cánceres; por otra parte se sabe que el inhibidor más abundante de estas enzimas proteolíticas, el inhibidor alfa-1-proteinasa (IAP) está aumentando en los pacientes con diferentes cánceres. Nosotros y otros investigadores hemos demostrado que apesar del aumento cuantitativo de IAP su función inhibitoria está relativamente disminuida. Nuestro objetivo fue el investigar la actividad inhibitoria del IAP en diferentes estadios del carcinoma de cérvix uterino. Se estudiaron pacientes con displasia cervical, con carcinoma in situ y con carcinoma invasor. El IAP se cuantificó con nefelometría Laser y la capacidad inhibitoria de tripsina (CIT), por el método de Liebermann. Se calculó el indice CIT/IAP y se realizó un estudio estadístico de los valores obtenidos. Las displasias no mostraron diferencias estadísticamente significativas con los testigos; sin embargo, 82% de los pacientes con carcinoma in situ y 87.3% de aquellos con carcinoma invasor mostraron valores IAP arriba de 2 D.S. del promedio. No se encontró ninguna diferencia significativa de los valores del CIT en ninguno de los grupos, pero el índice CIT/IAP disminuyó a 0.54 en el carcinoma in situ y a 0.56 en el carcinoma invasor, lo que indica una reducción de casi 50% de la función inhibitoria de la proteolisis. Estos hallazgos sugieren que la disminución relativa de la actividad antiproteolítica observada puede ser un factor determinante en favor de la progresión neoplásica