30 research outputs found

    Cytochrome P4504A inhibitors attenuate the exaggerated natriuretic response to volume expansion in thyroidectomized rats

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    Thyroidectomy augments the natriuretic response to volume expansion; however, the mechanism remains unknown. This study assessed the role of 20-hydroxyeicosatetraenoic acid (20-HETE) in the natriuretic response to an acute volume expansion in hypothyroid rats. Urine flow (1.9-fold), sodium excretion (2.4-fold), fractional sodium excretion (3.8-fold), and distal delivery of sodium (4.1-fold) increased to a greater extent in thyroidectomized rats (TX) than in sham-operated controls (SHAM) following i.v. infusion of isotonic saline (5% body weight) over 60 min. This was associated with inhibition of both proximal and distal tubular reabsorption of sodium. Administration of two mechanistic and chemical dissimilar inhibitors of the synthesis of 20- HETE, 1-aminobenzotriazole (ABT), and N-hydroxy-N?-(-4-butyl-2-methylphenyl) formamidine (HET0016) decreased the natriuretic response in TX rats. Glomerular filtration rate was lower in TX than in SHAM rats and was not altered by the CYP4A inhibitors. The expression, intrarenal distribution, and the formation of 20-HETE and expoxygenase metabolites of arachidonic acid were similar in the cortex and medulla of SHAM and TX rats. These results suggest that CYP4A-derived metabolites of arachidonic acid play an important role in the enhanced natriuretic response to volume expansion in hypothyroid rats even though TX did not alter the expression or activity of these enzymes.Fil: Colombero Rivas, Cecilia Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas; ArgentinaFil: Venara, Marcela Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas; ArgentinaFil: Gonzalez, Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas; ArgentinaFil: Roman, Richard J.. University Of Mississippi; Estados UnidosFil: Nowicki, Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas; Argentin

    Intracellular signaling pathways triggered by the stimulation of the G-coupled Protein Receptor GPR75 by 20-hydroxyeicosatetraenoic acid (20-HETE) in androgen independent prostate cancer cells

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    20-HETE, the product of 20-hydroxylation of arachidonic acid by cytochrome P450 isoforms (CYP4F2 and CYP4A11), has a role in the oncogenesis of several human tumors. Recently, the GPR75 receptor has been identified as the target for 20-HETE. We have shown that androgen independent prostate cancer cells (PC-3) express GPR75. The aim of this study was to identify intracellular signaling molecules activated upon GPR75 stimulation by 20-HETE in PC-3 cells.Cells were incubated with 20-HETE (0.1 nM) in the presence or absence of the antagonist of the 20-HETE receptor, AAA (5 or 10 uM). Protein expression of the inducible focal adhesion protein Hydrogen Peroxide Inducible Clone-5 (HIC-5), the phosphorylated and total form of NF-kB, AKT, p38 MAP-Kinase (p38) and EGFR were assessed by western blot. Intracellular localization of p-AKT, NF-kB and PKCa were determined by immunofluorescence and subcellular fractionation. Migration of PC-3 cells incubated with diferentes inhibitors were evaluated by scratch wound healing assay. Results were analyzed using one-way ANOVA followed by Dunnet?s.Incubation with 20-HETE (2 h) increased the phosphorylation of EGFR, NF-kB and AKT by 146, 172 and 219%, respectively (vs control, p<0.01 for NF-kB, and p<0.001 for EGFR and AKT, n=3), and this was inhibited by AAA (vs 20-HETE alone, p<0.05 for NF-kB, p<0.01 for AKT and p<0.001 for EGFR). AAA alone increased p-38 phosphorylation by 248% (p<0.001 vs control, n=3). 20-HETE (1 h) induced the translocation of p-AKT to the nuclei (p<0.001, n=3) and promoted the redistribution of PKCa out of the nuclei (p<0.05, n=3) to the plasma membrane (p<0.001). Both effects were inhibited by AAA (vs 20-HETE, p<0.01 for AKT and p<0.05 for PKCa). AAA alone reduced the nuclear signal of p-AKT and NF-kB usually activated in tumoral cells (p<0.001 for both, n=3). Additionally, 20-HETE (12 h) increased by 150% the protein expression of Hic-5 (p<0.0001, n=5) and this was abolished by AAA (p<0.001).Our results show that 20-HETE modulates signaling pathways known to be deregulated in malignant cells through the GPR75-axis.Fil: Cardenas, Sofía. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Colombero, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Panelo, Laura Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Dakarapu, Rambabu. University of Texas. Southwestern Medical Center; Estados UnidosFil: Falck, John. University of Texas. Southwestern Medical Center; Estados UnidosFil: Costas, Monica Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Nowicki, Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaReunión anual de las Sociedades de BiocienciaMar del PlataArgentinaSociedad Argentina de Investigación ClínicaAsociación Argentina de Farmacología ExperimentalSociedad Argentina de BiologíaAsociación Argentina de Ciencia y Tecnología de Animales de LaboratorioSociedad Argentina de Protozoologí

    Economía, Sociedad y Procesos Hegemónicos en la Provincia de Misiones (ESOHE). 16H328

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    Actividades desarrolladas durante el período: Desde mediados de año se ha instalado un Taller Continuo que funciona los días viernes destinado a la puesta en común de información y la discusión de la marcha general del proyecto. El taller, se ha constituido en caja de resonancia de los avances y dificultades que se presentan y como el espacio donde se distribuyen tareas y responsabilices, se analizan las actividades y los aportes personales o de los integrantes de cada grupo responsable de alguna línea de investigación y se incorporan ideas y señalamientos. En este marco, se ha programado también un Ciclo de Lecturas teóricas y metodológicas que colaboran en la construcción de un lenguaje y una mirada común, necesaria para armonizar la labor de investigadores y becarios de postgrado con trayectorias disciplinares y experiencias muy disímiles; En la investigación sobre la historia económica de Misiones se ha avanzado en los siguientes puntos: Construcción de una periodización basada en ciclos económicos. Se trabaja en el reconocimiento y exploración de repositorios y fuentes escritas existentes a nivel local. exhaustivo relevamiento de las tesis de grado y postgrado, tanto en historia como en Antropología, existentes en las bibliotecas de la UNaM, referidas a temas empresariales y o al funcionamiento de las elites del poder. Se ha tomado contacto y accedido a ámbitos empresariales como las cámaras de la construcción, que en Misiones son 5, de PyMES y la Delegación Provincial de la Cámara Argentina de la Construcción que reúne a grandes empresas; Un grupo de investigadores y auxiliares del ESOHE está investigando los procesos de transformación del sistema educativo provincial (incluyendo tanto la componente pública como la privada), entendiendo que el sistema escolar es una de las instancias donde se socializa ideológicamente a la población y se promueven “sentidos de la realidad”; Entre las tareas en ejecución cabe mencionar: Lectura y fichaje de materia bibliográfico destinado a la actualización reajuste del encuadre teórico-metodológico. Identificación y caracterización de diferentes actores: funcionarios gubernamentales, empresas constructoras, e inmobiliarias, medios de comunicación, asociaciones civiles y otras organizaciones, grupos de interés y afectados por las obras que intervienen en la producción, disputa, apropiación y uso del espacio urbano en las ciudades de Encarnación y Posadas, Garupá y Candelaria. Elección y contacto de informantes calificados. Relevamiento de políticas y/o programas de intervención urbana a ambos lados de la frontera y sus procesos resultantes. Geo-referenciamiento de áreas de revalorización urbana, comerciales, de relegación y desplazamiento, así como de asentamientos precarios y zonas residenciales para sectores de alto poder adquisitivo. El trabajo realizado en esta primera etapa ha permitido avanzar en: Revisión bibliográfica; Redefinición del marco teórico de la investigación; Análisis de algunas relaciones concretas establecidas entre el estado y el sector civil organizado, en particular en el campo de las actividades económicas del tercer sector y en el marco de la implementación de planes y programas públicos; Análisis de las tensiones entre prácticas políticas y económicas que se desatan en el proceso de generación y funcionamiento de los emprendimientos productivos auto-gestionados y cooperativas de trabajo

    Design and baseline characteristics of the finerenone in reducing cardiovascular mortality and morbidity in diabetic kidney disease trial

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    Background: Among people with diabetes, those with kidney disease have exceptionally high rates of cardiovascular (CV) morbidity and mortality and progression of their underlying kidney disease. Finerenone is a novel, nonsteroidal, selective mineralocorticoid receptor antagonist that has shown to reduce albuminuria in type 2 diabetes (T2D) patients with chronic kidney disease (CKD) while revealing only a low risk of hyperkalemia. However, the effect of finerenone on CV and renal outcomes has not yet been investigated in long-term trials. Patients and Methods: The Finerenone in Reducing CV Mortality and Morbidity in Diabetic Kidney Disease (FIGARO-DKD) trial aims to assess the efficacy and safety of finerenone compared to placebo at reducing clinically important CV and renal outcomes in T2D patients with CKD. FIGARO-DKD is a randomized, double-blind, placebo-controlled, parallel-group, event-driven trial running in 47 countries with an expected duration of approximately 6 years. FIGARO-DKD randomized 7,437 patients with an estimated glomerular filtration rate >= 25 mL/min/1.73 m(2) and albuminuria (urinary albumin-to-creatinine ratio >= 30 to <= 5,000 mg/g). The study has at least 90% power to detect a 20% reduction in the risk of the primary outcome (overall two-sided significance level alpha = 0.05), the composite of time to first occurrence of CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure. Conclusions: FIGARO-DKD will determine whether an optimally treated cohort of T2D patients with CKD at high risk of CV and renal events will experience cardiorenal benefits with the addition of finerenone to their treatment regimen. Trial Registration: EudraCT number: 2015-000950-39; ClinicalTrials.gov identifier: NCT02545049

    L-Dopa uptake and dopamine production in proximal tubular cells are regulated by β\u3csub\u3e2\u3c/sub\u3e-adrenergic receptors

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    This study assessed the role of adrenergic receptors on the regulation of the uptake of L-dopa and the production of dopamine by renal tubular cells. Scatchard analysis showed two L-dopa uptake sites with different affinities (K(m) 0.316 vs 1.53 μM). L-Dopa uptake was decreased by the nonselective adrenergic agonists epinephrine or norepinephrine (40%), by the β-selective agonist isoproterenol or the β2-selective agonist terbutaline (60%), but not by α-selective agonists (all 1 μM). The effect of norepinephrine, isoproterenol, or terbutaline was unaffected by addition of the β1-antagonist atenolol, abolished by ICI-118,551, a β2-antagonist (both 0.1 μM), and mimicked by the addition of dibutyryl-cAMP (1 μM). Preincubation with terbutaline decreased the number of high-affinity uptake sites (V(max) = 1.10 ± 0.3 vs. 0.5 ± 0.1 pmol · mg protein-1 · min-1) without changing their affinity. Norepinephrine or terbutaline decreased dopamine production by isolated cells, and this effect was abolished by ICI-118,551 (0.1 μM). In vivo administration of ICI-118,551 reduced the urinary excretion of L-dopa and increased the excretion of 3,4-dihydroxyphenylacetic acid without significant changes in plasma L-dopa concentrations. These results demonstrate that stimulation of β2-adrenergic receptors decreases the number of high-affinity L-dopa uptake sites in isolated tubular cells resulting in a reduction of the uptake of L-dopa and the production of dopamine and provide evidence for the presence of this mechanism in the intact animal

    Signaling cascade of insulin-induced stimulation of L-dopa uptake in renal proximal tubule cells

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    The inward L-dihydroxyphenylalanine (L-dopa) transport supplies renal proximal tubule cells (PTCs) with the precursor for dopamine synthesis. We have previously described insulin-induced stimulation of L-dopa uptake into PTCs. In the present paper we examined insulinrelated signaling pathways involved in the increase of L-dopa transport into isolated rat PTCs. Insulin (50?500 U/ml) increased L-dopa uptake by PTCs, reaching the maximal increment (60% over the control) at 200 U/ml. At this concentration, insulin also increased insulin receptor tyrosine phosphorylation. Both effects were abrogated by the tyrosine kinase inhibitor genistein (5 M). In line, inhibition of the protein tyrosine phosphatase by pervanadate (0.2?100 M) caused a concentration-dependent increase in both the uptake of L-dopa (up to 400%) and protein tyrosine phosphorylation. A synergistic effect between pervanadate and insulin on L-dopa uptake was observed only when threshold (0.2 M), but not maximal (5 M), concentrations of pervanadate were assayed. Insulin-induced stimulation of L-dopa uptake was also abolished by inhibition of phosphatidylinositol 3-kinase (PI3K; 100 nM wortmannin, and 25 M LY-294002) and protein kinase C (PKC; 1 M RO-318220). Insulin-induced activation of PKC- was confirmed in vitro by its translocation from the cytosol to the membrane fraction, and in vivo by immunohistochemistry studies. Insulin caused a wortmannin-sensitive increase in Akt/protein kinase B (Akt/PKB) phosphorylation and a dose-dependent translocation of Akt/PKB to the membrane fraction. Our findings suggest that insulin activates PKC- , and Akt/PKB downstream of PI3K, and that these pathways contribute to the insulin-induced increase of L-dopa uptake into PTCs.Fil: Carranza, Maria Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Musolino, Patricia L.. Universidad Austral. Facultad de Ciencias Biomédicas; ArgentinaFil: Villar, Marcelo Jose. Universidad Austral. Facultad de Ciencias Biomédicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Nowicki, Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; Argentin

    Distribution and characterization of nitric oxide synthase in the nervous system of Triatoma infestans (insecta: heteroptera)

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    The biochemical characterization of nitric oxide synthase (NOS) and its distribution in the central nervous system (CNS) were studied in the heteropteran bug Triatoma infestans. NOS-like immunoreactivity was found in the brain, subesophageal ganglion, and thoracic ganglia by using immunocytochemistry. In the protocerebrum, NOS-immunoreactive (IR) somata were detected in the anterior, lateral, and posterior soma rinds. In the optic lobe, numerous immunostained somata were observed at the level of the first optic chiasma, around the lobula, and in the proximal optic lobe. In the deutocerebrum, NOS-IR perikarya were mainly observed in the lateral soma rind, surrounding the sensory glomeruli, and a few cell bodies were seen in association with the antennal mechanosensory and motor neuropil. No immunostaining could be detected in the antennal nerve. The subesophageal and prothoracic ganglia contained scattered immunostained cell bodies. NOS-IR somata were present in all the neuromeres of the posterior ganglion. Western blotting showed that a universal NOS antiserum recognized a band at 134 kDa, in agreement with the expected molecular weight of the protein. Analysis of the kinetics of nitric oxide production revealed a fully active enzyme in tissue samples of the CNS of T. infestans.Fil: Settembrini, Beatriz Patricia. Universidad Austral. Facultad de Ciencias Biomédicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Coronel, Maria Florencia. Universidad Austral. Facultad de Ciencias Biomédicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Nowicki, Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Nighorn, Alan J.. University of Arizona; Estados UnidosFil: Villar, Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigación en Biomedicina de Buenos Aires - Instituto Partner de la Sociedad Max Planck; Argentina. Universidad Austral. Facultad de Ciencias Biomédicas; Argentin

    Inhibitors of 20-hydroxyeicosatetraenoic acid (20-HETE) formation attenuate the natriuretic effect of dopamine

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    Endogenous renal dopamine is a major physiological regulator of renal ion transport; however its intracellular signaling pathways are not thoroughly understood. The present study examined the role of 20-hydroxyeicosatetraenoic acid (20-HETE), the major cytochrome P450 (CYP4A) metabolite of arachidonic acid formed in the renal cortex, on the natriuretic response to dopamine in Sprague Dawley rats. Infusion of dopamine (1.5 μg/kg/min, i.v.) increased urine flow (1.9 fold over basal), sodium excretion (UNaV, 2.7 fold), fractional sodium excretion (FENa, 3.3 fold) and proximal and distal delivery of sodium by 1.5- and 2-fold respectively. Administration of two inhibitors of the synthesis of 20-HETE, 1-aminobenzotriazole (ABT) and N-hydroxy-N′-(-4-butyl-2- methylphenyl)formamidine (HET0016) reduced the response to dopamine by 65%. Induction of the renal expression of CYP4A enzymes with clofibrate did not alter the response to dopamine. The natriuretic response to dopamine was lower in Dahl salt-sensitive rats in comparison to an SS.BN5 consomic strain in which transfer of chromosome 5 from Brown Norway to Dahl salt-sensitive rats upregulates the renal expression of CYP4A protein and the production of 20-HETE. Treatment with HET0016 blocked the renal effects of dopamine in SS.BN5 rats. We also examined the influence of 20-HETE in the natriuretic response to acute volume expansion that is in part mediated via the release of endogenous dopamine. The increase in urine flow, UNaV, FENa and distal FENa following volume expansion was markedly reduced in rats treated with ABT. These results suggest that 20-HETE plays at least a permissive role in the natriuretic response to dopamine.Fil: Federik Fernandez, Maria M.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Gonzalez, Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; ArgentinaFil: Williams, Jan M.. University of Mississippi; Estados UnidosFil: Roman, Richard J.. University of Mississippi; Estados UnidosFil: Nowicki, Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Gobierno de la Ciudad de Buenos Aires. Centro de Investigaciones Endocrinológicas "Dr. César Bergada". Fundación de Endocrinología Infantil. Centro de Investigaciones Endocrinológicas "Dr. César Bergada"; Argentin
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