Aldosterona e IL-17 en la génesis de la hipertensión arterial mineralocorticoídea, un estudio ex vivo / Aldosterone and il-17 in the genesis of mineralocorticoid arterial hypertension: an ex vivo study

Background: Treatment of dendritic cells (DC) with aldosterone induces the secretion of IL-6 and TGF-beta. The polarization of naïve T cells to helper 17 T lymphocytes with DCs pre-incubated with aldosterone, has been described in vivo, generating an IL-17 hyper-secreting phenotype, a cytokine associated with cardiac and renal fibrosis. There are mineralocorticoid receptors (MR) in immune cells and their activation may determine the inflammatory (M1) or adaptive (M2) macrophage phenotype. Aldosterone levels could regulate immunogenic gene expression in these cells, modulating the liberation of specific cytokines. Aim: To assess in humans the association of aldosterone levels and IL-17 with inflammatory markers in peripheral blood mononuclear cells (PBMC). Material and Methods: In blood samples of 176 participants aged 18 to 67 years (61 percent women) with a body mass index of 27.1 +/- 4.8 kg/m2, aldosterone, plasma renin activity (ARP), cortisol, C reactive protein, andIL-17 were measured. mRNA was isolated from PBMCs to measure the expression of MR RAC-1, HO-1, TLR-4, CD-14, NGAL and IL-17 by real time polymerase chain reaction. Results: Aldosterone correlated positively with ARP and the expression of CD-14 in PBMCs. Plasma levels of IL-17 were positively associated with the expression of MR, Rac1a and NGAL. Conclusions: Aldosterone and IL-17 levels were associated with inflammatory activation markers in PBMC, which could activate MRand promote a subclinical inflammatory status inducing hypertension.

Pérdida de glutatión desde pulmones de conejo en solución de preservación para trasplante: efectos clínicos y funcionales a corto plazo / Loss of glutathione from rabbit lungs in transplant preservation solution

Introduction: Ischemia-reperfusion injury causes morbidity and mortality in lung transplant patients. It is unknown if the usual lung preservation solution favors antioxidant deficiency and thus, increased oxidative stress in the receptor. Objective: To evaluate if there is any loss of glutathione from rabbit lungs to the preservation solution. Results: We found a decrease in lung total glutathione content, without an increase in the oxidized form of this antioxidant. At the same time, we were able to measure increasing levels of glutathione in the preservation solution from 30 min on. Conclusions: There is loss of glutathione from the lung to the preservation solution that is not mediated by glutathione oxidation and likely due to passage of the reduced form along the concentration gradient, rendering the tissue vulnerable to oxidative stress once in the receptor.

El daño por isquemia-reperfusión es causa de morbimortalidad en pacientes con trasplante pulmonar. Se desconoce si la solución de preservación habitual del pulmón puede contribuir a la deficiencia de antioxidantes, favoreciendo el estrés oxidativo en el receptor. Objetivo: Evaluar si existe pérdida de glutatión desde pulmones de conejo a la solución de preservación para trasplante. Resultados: Encontramos una disminución en el contenido de glutatión total del pulmón, sin aumento en el contenido de glutatión oxidado. Esto se asoció a la aparición y aumento sostenido de glutatión en la solución de preservación desde los 30 min. Conclusiones: Existe salida de glutatión desde el pulmón no mediada por oxidación de éste y posiblemente favorecida por el gradiente de concentración de glutatión reducido. Esta pérdida deja al tejido vulnerable frente a las condiciones de estrés oxidativo en el receptor.

Magnitud del enfisema inducido por elastasa: posible relación con el tipo de daño agudo pulmonar / Elastase induced emphysema: possible relationship with the type of acute lung injury

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.

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.

El colágeno de la reestenosis post angioplastia con stent: ¿se origina en la íntima o en la adventicia? / Origin of collagen in restenosis post stenting: intima or adventitia?

Background: Restenosis post stenting is due to the deposit of extracellular matrix, mainly collagen in the neointima. Controversy exists regarding if collagen is generated locally or by immigration from the adventitia. Aim: To study the fibrocellular response after stent implantation in rabbit iliac arteries. To observe, by immunohistochemistry and in situ hybridization, if collagen type I mRNA is expressed in the neointima, in the media or in the adventitia. Material and methods: Thirty eight white rabbits (New Zealand) of 4 kg received an hypercholesterolemic diet during 1 month. After this period, in all but 6 of them, an angioplasty with stent implantation was performed via right carotid artery in both iliac arteries, using a 1:1.3 relationship regarding the reference vessel. Angiograms were performed at day 0, 4, 21, and 40, followed by paraffin fixation of the injured segments, immunohistochemistry for a-actin and in situ hybridization to detect procollagen type I (a1R1) mRNA. Results: No hybridization was observed in non injured arteries or at day 0 (n= 6). Expression of a1R1 mRNA was observed in the neointima starting at day 4 after stenting (n= 8). At day 21 (n= 8) hybridization of procollagen type I was not only observed in the neointima, but also in the media, which became equally intense in both areas. At day 40 (n= 6) hybridization was observed similarly in the media and adventitia. Conclusions: In this model, hybridization of procollagen type I started in the neointima, then involved the media and finally the adventitia. This finding might be useful for designing therapies to be delivered locally at the end of an angioplasty to prevent collagen deposition in the neointima