Jessica Tijero

A New Experimental Model of Acid and Endotoxin-Induced Acute Lung Injury in Rats

The majority of the animal models of acute lung injury (ALI) are focused on the acute phase. This limits the studies of the mechanisms involved in later phases and the effects of long-term treatments. Thus the goal of this study was to develop an experimental ALI model of aspiration pneumonia, in which diffuse alveolar damage continues for 72 h. Rats were intratracheally instilled with one dose of HCl (0.1 mol/l) followed by another instillation of one dose of LPS (0, 10, 20, 30, or 40 μg/g body weight) 2 h later, which models aspiration of gastric contents that progresses to secondary lung injury from bacteria or bacterial products. The rats were euthanized at 24, 48, and 72 h after the last instillation. The results showed that HCl and LPS at all doses caused activation of inflammatory responses, increased protein permeability and apoptosis, and induced mild hypoxemia in rat lungs at 24 h postinstillation. However, this lung damage was present at 72 h only in rats receiving HCl and LPS at the doses of 30 and 40 μg/g body wt. Mortality (∼50%) occurred in the first 48 h and only in the rats treated with HCl and LPS at the highest dose (40 μg/g body wt). In conclusion, intratracheal instillation of HCl followed by LPS at the dose of 30 μg/g body wt results in severe diffuse alveolar damage that continues at least 72 h. This rat model of aspiration pneumonia-induced ALI will be useful for testing long-term effects of new therapeutic strategies in ALI.

Role of heparin in pulmonary cell populations in an in-vitro model of acute lung injury.

BackgroundIn the early stages of acute respiratory distress syndrome (ARDS), pro-inflammatory mediators inhibit natural anticoagulant factors and initiate an increase in procoagulant activity. Previous studies proved the beneficial effects of heparin in pulmonary coagulopathy, which derive from its anticoagulant and anti-inflammatory activities, although it is uncertain whether heparin works. Understanding the specific effect of unfractioned heparin on cell lung populations would be of interest to increase our knowledge about heparin pathways and to treat ARDS.MethodsIn the current study, the effect of heparin was assessed in primary human alveolar macrophages (hAM), alveolar type II cells (hATII), and fibroblasts (hF) that had been injured with LPS.ResultsHeparin did not produce any changes in the Smad/TGFß pathway, in any of the cell types evaluated. Heparin reduced the expression of pro-inflammatory markers (TNF-α and IL-6) in hAM and deactivated the NF-kß pathway in hATII, diminishing the expression of IRAK1 and MyD88 and their effectors, IL-6, MCP-1 and IL-8.ConclusionsThe current study demonstrated that heparin significantly ameliorated the cells lung injury induced by LPS through the inhibition of pro-inflammatory cytokine expression in macrophages and the NF-kß pathway in alveolar cells. Our results suggested that a local pulmonary administration of heparin through nebulization may be able to reduce inflammation in the lung; however, further studies are needed to confirm this hypothesis.

Nebulized Heparin Attenuates Pulmonary Coagulopathy and Inflammation through Alveolar Macrophages in a Rat Model of Acute Lung Injury

Objective  Alveolar macrophages play a key role in the development and resolution of acute respiratory distress syndrome (ARDS), modulating the inflammatory response and the coagulation cascade in lungs. Anti-coagulants may be helpful in the treatment of ARDS. This study investigated the effects of nebulized heparin on the role of alveolar macrophages in limiting lung coagulation and inflammatory response in an animal model of acute lung injury (ALI). Methods  Rats were randomized to four experimental groups. In three groups, ALI was induced by intratracheal instillation of lipopolysaccharide (LPS) and heparin was nebulized at constant oxygen flow: the LPS/Hep group received nebulized heparin 4 and 8 hours after injury; the Hep/LPS/Hep group received nebulized heparin 30 minutes before and 4 and 8 hours after LPS-induced injury; the LPS/Sal group received nebulized saline 4 and 8 hours after injury. The control group received only saline. Animals were exsanguinated 24 hours after LPS instillation. Lung tissue, bronchoalveolar lavage fluid (BALF) and alveolar macrophages isolated from BALF were analysed. Results  LPS increased protein concentration, oedema and neutrophils in BALF as well as procoagulant and proinflammatory mediators in lung tissue and alveolar macrophages. In lung tissue, nebulized heparin attenuated ALI through decreasing procoagulant (tissue factor, thrombin–anti-thrombin complexes, fibrin degradation products) and proinflammatory (interleukin 6, tumour necrosis factor alpha) pathways. In alveolar macrophages, nebulized heparin reduced expression of procoagulant genes and the effectors of transforming growth factor beta (Smad 2, Smad 3) and nuclear factor kappa B (p-selectin, CCL-2). Pre-treatment resulted in more pronounced attenuation. Conclusion  Nebulized heparin reduced pulmonary coagulopathy and inflammation without producing systemic bleeding, partly by modulating alveolar macrophages.

Intratracheal instillation of alveolar type II cells enhances recovery from acute lung injury in rats

BACKGROUND Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are characterized by excess production of inflammatory factors. Alveolar type II (ATII) cells help repair damaged lung tissue, rapidly proliferating and differentiating into alveolar type I cells after epithelial cell injury. In ALI, the lack of viable ATII favors progression to more severe lung injury. ATII cells regulate the immune response by synthesizing surfactant and other anti-inflammatory proteins and lipids. Cross-talk between ATII and other cells such as macrophages may also be part of the ATII function. The aim of this study was to test the anti-inflammatory and reparative effects of ATII cells in an experimental model of ALI. METHODS In this study ATII cells (2.5 × 106 cells/animal) were intratracheally instilled in rats with HCl and lipopolysaccharide (LPS)-induced ALI and in healthy animals to check for side effects. The specific effect of ATII cells was compared with fibroblast transplantation. RESULTS ATII cell transplantation promoted recovery of lung function, decrease mortality and lung inflammation of the animals with ALI. The primary mechanisms for benefit were paracrine effects of prostaglandin E2 (PGE2) and surfactant protein A (SPA) released from ATII cells that modulate alveolar macrophages to an anti-inflammatory phenotype. To our knowledge, these data are the first to provide evidence that ATII cells secrete PGE2 and SPA, reducing pro-inflammatory macrophage activation and ALI. CONCLUSION ATII cells and their secreted molecules have shown an ability to resolve ALI, thereby highlighting a potential novel therapeutic target.

Effects of nebulized heparin on pulmonary inflammation in a rat model of acute lung injury

Introduction: Sepsis is a mayor cause of acute respiratory distress syndrome (ARDS). In sepsis, the anticoagulant system is impaired. Nebulization of anticoagulants might allow for higher pulmonary concentration and reduce the risk of systemic bleeding. Objectives: To assess the effects of nebulized heparin in a rat model of acute lung injury. Methods: Adult male Sprague-Dawley rats (250-300 g; n=8/group) were subjected to intratracheal administration (IA) of LPS (10 μg/g b.w.). Saline or heparin (1000 IU/kg) were nebulized at 4 and 8h after LPS instillation. Animals were sacrificed 24h after the injury. Inflammatory cells and total proteins were assessed in bronchoalveaolar lavage fluid (BALF). IL-6, GROKC and TNFA were measured in lung homogenate by multiplex assay. Data are reported as mean±SD. One-way ANOVA was used for multigroup comparisons. Results: In BALF, nebulized heparin significantly reduced neutrophils in animals instilled with LPS (12±4x107 cells/ml) compared to animals administrated with LPS and nebulized with saline (18±6x107 cells/ml, p Conclusions: Our results showed that nebulized heparin administration reduced pulmonary inflammatory response in a rat model of acute lung injury.

Novel experimental model of maintained acute lung injury

Resumen del poster presentado al 50th Inner Ear Biology Workshop, celebrado en Alcala de Henares-Madrid (Espana) del 10 al 13 de septiembre de 2013.Resumen del trabajo presentado al 15o Congreso Nacional de la Sociedad Espanola de Neurociencia (SENC) celebrado en Oviedo del 25 al 27 de septiembre de 2013.Resumen del poster presentado al CIBERDEM Annual Meeting, celebrado en Cerdanyola del Valles, Barcelona (Espana) del 11 al 13 de mayo de 2016.-- et al.Resumen del trabajo presentado al XXXVIII Congreso de la Sociedad Espanola de Ciencias Fisiologicas (SECF), celebrado en Zaragoza del 13 al 16 de septiembre de 2016.Poster presentado en el XI European Meeting on Glial Cells in Health and Disease, celebrado los dias 3 al 6 de julio de 2013 en Berlin (Alemania)Memoria presentada para optar al grado de Doctor por la Licenciada en Biologia Angela Prieto Folgado y realizada en el Instituto de Investigaciones Biomedicas Alberto Sols.La realizacion de este trabajo ha sido posible gracias a la financiacion otorgada por el FIS al proyecto de investigacion 96/1803.Grant Funding Source: Supported by the Fondo de Investigaciones Sanitarias (PI0011406) to MF.The chemotherapeutic study of a limited series of steroidal sapogenins from several endemic species of the flora of the Canary Islands is presented here. On the whole, they possess a very weak antibacterial activity, a slight antifungal effect and one of them, vespertilin, displays interesting cytostatic activity (ID50 = 5 micrograms/ml). A pharmacodynamic screening carried out on this product mainly revealed very slight toxicity, antihistaminic activity and a light tranquilizing effect. The data obtained justify further research.The purpose of this study was to characterize the role of ions other than Ca2+ in hepatic responses to alpha 1-adrenergic stimulation. We report that the alpha 1-adrenoreceptor activation of hepatic functions is accompanied by extracellular acidification and an increase in intracellular pH. These effects are dependent on extracellular Na+ concentration and are inhibited by the Na+/H+ antiporter blocker 5-(N-ethyl-N-isopropyl) amiloride under conditions that preclude antagonistic effects on agonist binding. Thus, the activation of plasma membrane Na+/H+ exchange is an essential feature of the hepatic alpha-adrenoreceptor-coupled signaling pathway. The following observations indicate that the sustained hepatic alpha 1-adrenergic actions rely on a functional coupling between the plasma membrane Na+/H+ and Na+/Ca2+ exchangers, resulting in the stimulation of Ca2+ influx. 1) Inhibition of the Na+/K(+)-ATPase does not prevent the alpha 1-adrenergic effects. However, alpha 1-adrenoreceptor stimulation fails to induce intracellular alkalinization and to acidify the extracellular medium in the absence of extracellular Ca2+. 2) A non-receptor-induced increase in intracellular Na+ concentration, caused by the ionophore monensin, stimulates Ca2+ influx and increases vascular resistance. 3) Inhibition of Na+/Ca2+ exchange prevents, in a concentration-dependent manner, most of the alpha 1-agonist-induced responses. 4) The actions of Ca(2+)-mobilizing vasoactive peptide receptors or alpha 2-adrenoreceptors, which produce neither sustained extracellular acidification nor release of Ca2+, are insensitive to Na+/H+ exchange blockers.Poster presentado en la VII Reunion Anual de la Red Tematica de Investigacion Cooperativa en Cancer (RTICC), celebrada en Salamanca el 24 de septiembre de 2014Resumen del trabajo presentado al VI Meeting de la Red Espanola de Canales Ioniocs (RECI), celebrado en Santiago de Compostela del 6 al 8 de septiembre de 2017.Tesis Doctoral presentada por Laura Jimenez Perez para optar al grado de doctor por la Universidad de Valladolid, Departamento de Bioquimica y Biologia Molecular y FisiologiaPoster presentado en la VII Reunion Anual de la Red Tematica de Investigacion Cooperativa en Cancer (RTICC), celebrada en Salamanca el 24 de septiembre de 2014Resumen del trabajo presentado al XXXXVIII Congreso de la Sociedad Espanola de Bioquimica y Biologia Molecular (SEBBM), celebrado en Valencia del 7 al 10 de septiembre de 2015.Esta Tesis Doctoral fue realizada en el Centro Andaluz de Biologia del Desarrollo por la licenciada Briseida Beli Cacho Valadez para optar al grado de Doctor por la Universidad Pablo de Olavide.Rat liver S-adenosylmethionine (AdoMet) synthetase appears as high-M(r) (tetramer) and low-M(r) (dimer) forms. Both are inhibited in the presence of GSSG at pH 8. The calculated Ki values are 2.14 and 4.03 mM for the high- and low-M(r) forms, respectively. No effect on enzyme activity was observed in the presence of GSH, but modulation of inhibition by GSSG can be obtained by addition of GSH. At a total glutathione concentration (GSH + GSSG) of 10 mM, a KOX of 1.74 was calculated for the high-M(r) form, whereas this constant was 2.85 for the low-M(r) AdoMet synthetase. No incorporation of [35S]GSSG was observed in either of the enzyme forms, and inhibition of enzyme activity was correlated with dissociation of both AdoMet synthetases to a monomer. The data obtained in the presence of GSSG seem to suggest that oxidation leads to the formation of an intrasubunit disulfide. The possible regulation of AdoMet synthetase activity by the GSH/GSSG ratio is discussed, as well as its in vivo significance.Trabajo presentado en el XI Simposi de Neurobiologia: Future technical advances, organizado por la Socitat Catalana de Biologia, en Barcelona, los dias 12 y 13 de noviembre de 2018El estudio de la relacion entre componentes de la dieta y la salud/enfermedad utiliza metodos de valoracion de la ingesta dietetica, del estatus nutricional y de marcadores de funcion o de efecto. En concreto, en el estudio de los carotenoides y la salud ocular, interesa el estudio de dos carotenoides sin actividad provitamina A, la luteina y la zeaxantina, por su posible papel en la optimizacion de la funcion visual y en la prevencion de enfermedades cronicas asociadas a la edad, y de tres carotenoides con actividad provitamina A: -caroteno, -caroteno y -criptoxantina, por ser precursores de retinol, nutriente del que depende el ciclo visual para una vision normal. En el presente trabajo se ha llevado a cabo el estudio de los carotenoides de la dieta mas relevantes para la salud ocular humana considerando de forma simultanea parametros relacionados con la ingesta, el estatus y la funcion visual, asi como diversas variables que pueden modificar el estatus nutricional, como son la concentracion de lipidos en sangre, y la bioaccesibilidad de los carotenoides a partir de alimentos de amplio consumo...Fetal rat hepatocytes treated with transforming growth factor beta (TGF-beta) die by apoptosis. However, a subpopulation of them survives and undergoes an epithelial mesenchymal transition (EMT). This transition also occurs upon incubation with fetal bovine serum. We have isolated the subpopulations that undergo EMT (TGF-beta-treated-fetal hepatocytes: TbetaT-FH; serum-treated-fetal hepatocytes: ST-FH) and show that they present high levels of vimentin and Snail expression and lack cytokeratin 18 and E-cadherin. Both TbetaT-FH and ST-FH cells require mitogens to grow and maintain the response to TGF-beta in terms of growth inhibition. However, they lack differentiation markers such as the liver-enriched transcription factors hepatocyte nuclear factor 4 (HNF-4) or HNF-1alpha and express the progenitor marker OV-6. Interestingly, the EMT process confers them resistance to the apoptotic effect of TGF-beta, with cells showing higher levels of active AKT and Bcl-x(L) than fetal hepatocytes. In summary, these cells are refractory to the apoptotic effects of TGF-beta, showing characteristics of liver progenitors and of some hepatocellular carcinoma cells.Memoria de tesis presentada por Luis Vazquez Fonseca, Licenciado en Bioquimica para optar al grado de Doctor. Esta Tesis Doctoral ha sido realizada bajo el programa de doctorado de Biotecnologia y Tecnologia Quimica en el grupo de investigacion del CIBERER U729 en el Centro Andaluz de Biologia del Desarrollo, Area de Biologia Celular del Departamento de Fisiologia, Anatomia y Biologia Celular de la Universidad Pablo de Olavide y bajo la direccion del Dr. Carlos Santos Ocana y el Dr. Placido NavasResumen del poster presentado al Joint FEPS & XXXVI Spanish Physiological Society Congress (Sociedad Espanola de Ciencias Fisiologicas) celebrado en Santiago de Compostela (Espana) del 8 al 11 de septiembre de 2012.Poster presentado al 17o Congreso Nacional de la Sociedad Espanola de Neurociencia, celebrado en Alicante del 27 al 30 de septiembre de 2017.The mutations at the bithorax locus produce a transformation of anterior haltere into anterior wing. The bx1 allele presents unusual features when compared with other bx alleles. The phenotype of bx1 homozygotes is temperature sensitive but only with regard to the distal and not to the proximal transformation, thus suggesting two different components in the bithorax transformation. The phenotype of bx1 homozygotes is stronger than that of bx1 over the deletion of the gene, suggesting a trans interaction of the bx1 chromosomes which results in mutual partial inactivation. We show by temperature shift and clonal analysis experiments that the decision on whether to differentiate haltere or wing structures is taken at the end of the proliferation period of the mutant disc.Poster presentado al XXXVII Congreso de la Sociedad Espanola de Bioquimica y Biologia Molecular, celebrado en Granada del 9 al 12 de septiembre de 2014.Poster presentado al XXVII Congreso Nacional de la Asociacion Espanola de Genetica Humana celebrado en Madrid del 10 al 12 de abril de 2013.Poster presentado al XXXVII Congreso de la Sociedad Espanola de Bioquimica y Biologia Molecular, celebrado en Granada del 9 al 12 de septiembre de 2014.Poster presentado en el XI European Meeting on Glial Cells in Health and Disease, celebrado los dias 3 al 6 de julio de 2013 en Berlin (Alemania)Resumen del trabajo presentado al Spanish Society of Biochemistry and Molecular Biology (SEBBM), celebrado en Madrid del 16 al 19 de julio de 2019.Poster presentado en el XII European Meeting on Glial Cells in Health and Disease, celebrado los dias 15 a 18 de julio de 2015 en Bilbao (Espana)Trabajo presentado en el XL Congreso de la Sociedad Espanola de Bioquimica y Biologia Molecular. FEBS3+1st Joint Meeting of the French-Portuguese-Spanish Biochemical and Molecular, celebrado en Barcelona (Espana), del 23 al 26 de octubre de 2017Resumen del poster presentado al Joint FEPS & XXXVI Spanish Physiological Society Congress (Sociedad Espanola de Ciencias Fisiologicas) celebrado en Santiago de Compostela (Espana) del 8 al 11 de septiembre de 2012.Trabajo presentado en el XII GEIRLI Meeting: New trends in redox biology: a multidisciplinary approach, celebrado en Barcelona (Espana), los dias 4 y 5 de julio de 2019Treatment of nucleosomal particles with dimethylmaleic anhydride, a reagent for protein amino groups, is accompanied by a biphasic release of histones H2A plus H2B; one H2A.H2B dimer is more easily released than the other. This behavior allows the preparation of nucleosomal particles containing only one H2A.H2B dimer, which were complemented with 125I-labeled H2A.H2B. These reconstituted particles, which contain one labeled and one unlabeled H2A.H2B dimer, were treated with the amount of reagent needed to release one of the two H2A.H2B dimers. Radioactivity was equally distributed between residual particles and released proteins, which is consistent with equivalent binding sites in the nucleosomal particle for H2A.H2B dimers, rather than with intrinsically different sites. The asymmetric release of H2A.H2B dimers would be caused by a change in the binding site of one dimer following the release of the other. This behavior might be related to the structural dynamics of nucleosomes.Resumen del trabajo presentado al European Society of Cardiology (ESC) Congress, celebrado en Barcelona (Espana) del 26 al 30 de agosto de 2017.Resumen del poster presentado al 49th European Association for the Study of Diabetes Annual Meeting, celebrado en Barcelona (Espana) del 23 al 27 de septiembre de 2013.-- et al.Trabajo doctoral realizado por Da Rebeca Lapresa Ruiz de Gauna, para optar al grado de doctor por la Universidad de Salamanca.Rationale: Several animal models have been developed to study acute lung injury (ALI); however the majority of these studies are focused on different mechanisms within the acute phase. These models do not allow studying the mechanisms in the later phases or testing any possible long-term treatment. The aim of this study was to develop an experimental ALI model simulating bronchial aspiration of gastric contents with bacterial superinfection with alveolar epithelial damage persisting over time. Methods: Sprague-Dawley rats (200-250g) were anesthetized with isofluorane. ALI was induced by intratracheal instillation of HCl (1 µl/g, 0.1 mol/L pH=1.4) followed by instillation of LPS from Escherichia coli O55:B5 (0, 10, 20, 30 or 40µg/g b.w.) two hours later. Control rats were treated with intratracheal instillations of saline. After 72h, the animals were sacrificed and bronchoalveolar lavage fluid (BALF) was sampled for further analysis of total protein concentration by bicinchoninic acid method. Results: At 72 h, rats suffered a significant loss of weight proportional to the administered dose of LPS (5.6% with 10µg/g b.w, 12.6% with 20µg/g b.w, 14.2% with 30µg/g b.w and 17.7% with 40µg/g b.w). Control rats gained in weight at 72h. LPS at 10, 20, 30 and 40µg/g b.w induced a 1.7, 2.5, 2.9 and 3.4 fold increase in total protein concentration in BAL fluid, respectively, reflecting a substantial increase proportional to the LPS dose. Conclusion: The degree of weight loss and the increase of total protein concentration in BAL fluid in the current model may reflect disease severity and progression. This model would be useful in future for new therapeutical options. Grant acknowledgements: FIS-PI12/02548 and Fundacio Parc Tauli.Resumen del trabajo presentado al European Respiratory Society (ERS) International Congress, celebrado en Paris (Francia) del 15 al 19 de septiembre de 2018.Resumen del trabajo presentado a las 5as Jornadas de Formacion del CIBERES celebradas en Bunyola (Mallorca) del 18 al 19 de octubre de 2012.Resumen del poster presentado al Joint FEPS & XXXVI Spanish Physiological Society Congress (Sociedad Espanola de Ciencias Fisiologicas) celebrado en Santiago de Compostela (Espana) del 8 al 11 de septiembre de 2012.Resumen del trabajo presentado al XIII Congreso de la Sociedad Espanola del Dolor, celebrado en Pamplona del 2 al 4 de junio de 2016.This work was supported by grants FIS-01/1048 and FIS-02/1199 from the Fondo de Investigacion Sanitaria and grant SA-087/01 from Junta de Castilla y Leon.Resumen del poster presentado al Joint Meeting of the American Physiological Society and the Physiological Society, celebrado en Dublin (Irlanda) del 29 al 31 de julio de 2016.Trabajo presentado al 5th International Conference on Phospholipase A2 Mediated Signaling in Translational Medicine celebrado en New Orleans (US) del 20 al 21 de mayo de 2013.Tesis Doctoral presentada por Rebeca Torres Merino para optar al grado de Doctora por la Universidad de Valladolid, Facultad de Medicina: Dpto. de Bioquimica y Biologia Molecular y Fisiologia.Poster presentado al Annual Meeting of the Association for Research in Vision and Ophthalmology (ARVO), celebrado en Seattle, Washington (US) del 1 al 5 de mayo de 2016.Resumen del trabajo presentado al 63rd Annual Meeting Biophysical Society, celebrado en Baltimore, Maryland (USA) del 2 al 6 de marzo de 2019.Poster presentado al XXXVII Congreso de la Sociedad Espanola de Bioquimica y Biologia Molecular, celebrado en Granada del 9 al 12 de septiembre de 2014.Resumen del poster presentado a la 5th Conference on Advances in Molecular Mechanisms Underlying Neurological Disorders (Joint conference of the European Society for Neurochemistry and the Biochemical Society) en la University of Bath (UK) del 23 al 26 de junio de 2013.-- Tambien presentado al 15o Congreso Nacional de la Sociedad Espanola de Neurociencia (SENC) celebrado en Oviedo del 25 al 27 de septiembre de 2013.Resumen del trabajo presentado al XXXVI Congreso de la Sociedad Espanola de Bioquimica y Biologia Molecular celebrado en Madrid del 4 al 6 de septiembre de 2013.Resumen del trabajo presentado a la 5th Conference on Advances in Molecular Mechanisms Underlying Neurological Disorders (Joint conference of the European Society for Neurochemistry and the Biochemical Society) en la University of Bath (UK) del 23 al 26 de junio de 2013.Resumen del poster presentado al XXVIII Congreso Nacional de la Sociedad Espanola de diabetes, celebrado en Bilbao del 20 al 22 de abril de 2016.SAF2016-77703-C2-2-R of the Ministerio de Economia y Competitividad, Spain and the European Regional Development Fund (ERDF); AGAUR 2017-SGR106 and the CERCA Programme of the Generalitat de Catalunya; C. Sanfeliu belong to Group 05 of CIBER Epidemiologia y Salud Publica (CIBERESP) of the Instituto de Salud Carlos III, Ministerio de Sanidad y Consumo, Spain