Identification and characterization of a novel elastase inhibitor from Hirudinaria manillensis / 中国天然药物

A large number of protease inhibitors have been found from leeches, which are essential in various physiological and biological processes. In the curret study, a novel elastase inhibitor was purified and characterized from the leech of Hirudinaria manillensis, which was named HMEI-A. Primary structure analysis showed that HMEI-A belonged to a new family of proteins. HMEI-A exerted inhibitory effects on elastase and showed potent abilities to inhibit elastase with an inhibition constant (K

Carum copticum and Thymus vulgaris oils inhibit virulence in Trichophyton rubrum and Aspergillus spp

Emergence of drug-resistant strains has demanded for alternative means of combating fungal infections. Oils of Carum copticum and Thymus vulgaris have long been used in ethnomedicine for ailments of various fungal infections. Since their activity has not been reported in particular against drug-resistant fungi, this study was aimed to evaluate the effects of oils of C. copticum and T. vulgaris on the growth and virulence of drug-resistant strains of Aspergillus spp. and Trichophyton rubrum. The gas chromatography-mass spectrometry analysis revealed thymol constituting 44.71% and 22.82% of T. vulgaris and C. copticum, respectively. Inhibition of mycelial growth by essential oils was recorded in the order of thymol > T. vulgaris > C. copticum against the tested strains. RBC lysis assay showed no tested oils to be toxic even up to concentration two folds higher than their respective MFCs. Thymol exhibited highest synergy in combination with fluconazole against Aspergillus fumigatus MTCC2550 (FICI value 0.187) and T. rubrum IOA9 (0.156) as determined by checkerboard method. Thymol and T. vulgaris essential oil were equally effective against both the macro and arthroconidia growth (MIC 72 µg/mL). A > 80% reduction in elastase activity was recorded for A. fumigatus MTCC2550 by C. copticum, T. vulgaris oils and thymol. The effectiveness of these oils against arthroconidia and synergistic interaction of thymol and T. vulgaris with fluconazole can be exploited to potentiate the antifungal effects of fluconazole against drug-resistant strains of T. rubrum and Aspergillus spp.

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.

Biochemical and histopathological changes in respiratory system of rats following exposure to diesel exhaust.

Effect of exposure to diesel exhaust (DE) for different durations was evaluated using histopathological and biochemical parameters in respiratory system of the rats. Animals were exposed to 1 part DE diluted with 5 parts of clean air in a simulation chamber for 15 min/day for 1, 7, 14 and 21 days. After completion of various exposures, biochemical parameters including elastase inhibitory capacity (EIC) and protein content of the bronchial airway lavage (BAL) and histopathological changes along with lung/body weight ratio were assessed. The elastase inhibitory capacity (an index of the protection against destruction of elastin, a lung connective tissue) was maximum at 1 week indicating thereby that the body renders protection against injury by increasing EIC levels in the initial phase. However, protein content in the BALF increased after 1 week and reached maximum at 2 weeks. Histopathological changes followed similar time course of pattern with accumulation of macrophages and protein exudation. Prolonged exposure up to 3 weeks, however was accompanied by chronic inflammatory changes and thickening of alveolar septa and blood vessels. Changes in lung/body weight ratio and suspended particulate matter (SPM) deposited on filters (simulation chamber) correlated well with EIC, protein content in BALF and histopathological changes. The biochemical findings accompanied with chronic structural changes in the lungs of rats following exposure to DE could be relevant to the clinical observation of increased incidence of chronic lung diseases after continued DE exposure.