Molecular aspects of intestinal calcium absorption

Intestinal Ca2+ absorption is a crucial physiological process for maintaining bone mineralization and Ca2+ homeostasis. It occurs through the transcellular and paracellular pathways. The first route comprises 3 steps: the entrance of Ca2+ across the brush border membranes (BBM) of enterocytes through epithelial Ca2+ channels TRPV6, TRPV5, and Cav1.3; Ca2+ movement from the BBM to the basolateral membranes by binding proteins with high Ca2+ affinity (such as CB9k); and Ca2+ extrusion into the blood. Plasma membrane Ca2+ ATPase (PMCA1b) and sodium calcium exchanger (NCX1) are mainly involved in the exit of Ca2+ from enterocytes. A novel molecule, the 4.1R protein, seems to be a partner of PMCA1b, since both molecules colocalize and interact. The paracellular pathway consists of Ca2+ transport through transmembrane proteins of tight junction structures, such as claudins 2, 12, and 15. There is evidence of crosstalk between the transcellular and paracellular pathways in intestinal Ca2+ transport. When intestinal oxidative stress is triggered, there is a decrease in the expression of several molecules of both pathways that inhibit intestinal Ca2+ absorption. Normalization of redox status in the intestine with drugs such as quercetin, ursodeoxycholic acid, or melatonin return intestinal Ca2+ transport to control values. Calcitriol [1,25(OH)2D3] is the major controlling hormone of intestinal Ca2+ transport. It increases the gene and protein expression of most of the molecules involved in both pathways. PTH, thyroid hormones, estrogens, prolactin, growth hormone, and glucocorticoids apparently also regulate Ca2+ transport by direct action, indirect mechanism mediated by the increase of renal 1,25(OH)2D3 production, or both. Different physiological conditions, such as growth, pregnancy, lactation, and aging, adjust intestinal Ca2+ absorption according to Ca2+ demands. Better knowledge of the molecular details of intestinal Ca2+ absorption could lead to the development of nutritional and medical strategies for optimizing the efficiency of intestinal Ca2+ absorption and preventing osteoporosis and other pathologies related to Ca2+ metabolism.Fil: Díaz de Barboza, Gabriela. Universidad Nacional de Cordoba. Facultad de Medicina. Catedra de Bioquimica y Biologia Molecular; ArgentinaFil: Guizzardi, Solange Natali. Universidad Nacional de Cordoba. Facultad de Medicina. Catedra de Bioquimica y Biologia Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Tolosa, Nori Graciela. Universidad Nacional de Cordoba. Facultad de Medicina. Catedra de Bioquimica y Biologia Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Glutathione depleting drugs, antioxidants and intestinal calcium absorption

Glutathione (GSH) is a tripeptide that constitutes one of the main intracellular reducing compounds. The normal content of GSH in the intestine is essential to optimize the intestinal Ca2+ absorption. The use of GSH depleting drugs such as DL-buthionine-S,R-sulfoximine, menadione or vitamin K3, sodium deoxycholate or diets enriched in fructose, which induce several features of the metabolic syndrome, produce inhibition of the intestinal Ca2+ absorption. The GSH depleting drugs switch the redox state towards an oxidant condition provoking oxidative/nitrosative stress and inflammation, which lead to apoptosis and/or autophagy of the enterocytes. Either the transcellular Ca2+ transport or the paracellular Ca2+ route are altered by GSH depleting drugs. The gene and/or protein expression of transporters involved in the transcellular Ca2+ pathway are decreased. The flavonoids quercetin and naringin highly abrogate the inhibition of intestinal Ca2+ absorption, not only by restoration of the GSH levels in the intestine but also by their anti-apoptotic properties. Ursodeoxycholic acid, melatonin and glutamine also block the inhibition of Ca2+ transport caused by GSH depleting drugs. The use of any of these antioxidants to ameliorate the intestinal Ca2+ absorption under oxidant conditions associated with different pathologies in humans requires more investigation with regards to the safety, pharmacokinetics and pharmacodynamics of them.Fil: Moine, Luciana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Rivoira, Maria Angelica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Díaz de Barboza, Gabriela Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Pérez, Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Tolosa, Nori Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentin

Spermatocyte apoptosis, which involves both intrinsic and extrinsic pathways, explains the sterility of Graomys griseoflavus Graomys centralis male hybrids

Spermatogenic impairment and the apoptotic pathways involved in establishing sterility of male hybrids obtained from crossing Graomys griseoflavus females with Graomys centralis males were studied. Testes from G. centralis, G. griseoflavus and hybrids were compared at different ages. Terminal transferase-mediated dUTP nick-end labelling assay (TUNEL), Fas, Bax and cytochrome c labelling were used for apoptosis evaluation, and calbindin D 28k staining as an anti-apoptotic molecule. In 1-month-old animals, spermatocytes were positive for all apoptotic markers, but moderate TUNEL (+) spermatocyte frequency was only found in G. centralis. At subsequent ages, the apoptotic markers were downregulated in testes from parental cytotypes, but not in hybrid testes. TUNEL (+) spermatocytes were present at 78% and 44% per tubule cross-section in 2- and 3-month-old hybrid animals, respectively. Pachytene spermatocyte death in adult hybrids occurs via apoptosis, as revealed by high caspase-3 expression. Calbindin was highly expressed in spermatocytes of adult hybrids, in which massive cell death occurs via apoptosis. Calbindin co-localisation with TUNEL or Fas, Bax and cytochrome c was very limited, suggesting an inverse regulation of calbindin and apoptotic markers. Hybrid sterility is due to breakdown of spermatogenesis at the pachytene spermatocyte stage. Both extrinsic and intrinsic pathways are involved in apoptosis of spermatocytes, which are the most sensitive cell type to apoptotic stimuli.Fil: Rodriguez, Valeria. Universidad Nacional de Córdoba. Facultad de Medicina. Cátedra de Bioquímica y Biología Molecular; ArgentinaFil: Díaz de Barboza, Gabriela Edith. Universidad Nacional de Córdoba. Facultad de Medicina. Cátedra de Bioquímica y Biología Molecular; ArgentinaFil: Ponce, Rubén Hugo. Universidad Nacional de Córdoba. Facultad de Odontología; ArgentinaFil: Merico, Valeria. Universita degli Studi di Pavia; ItaliaFil: Garagna, Silvia. Universita degli Studi di Pavia; ItaliaFil: Tolosa, Nori Graciela. Universidad Nacional de Córdoba. Facultad de Medicina. Cátedra de Bioquímica y Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentin

The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the Extended Baryon Oscillation Spectroscopic Survey and from the Second Phase of the Apache Point Observatory Galactic Evolution Experiment

The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14). This release makes the data taken by SDSS-IV in its first two years of operation (2014–2016 July) public. Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey; the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data-driven machine-learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from the SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS web site (www.sdss.org) has been updated for this release and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020 and will be followed by SDSS-V

Proyecto, investigación e innovación en urbanismo, arquitectura y diseño industrial

Actas de congresoLas VII Jornadas de Investigación “Encuentro y Reflexión” y I Jornadas de Investigación de becarios y doctorandos. Proyecto, investigación e innovación en Urbanismo, Arquitectura y Diseño Industrial se centraron en cuatro ejes: el proyecto; la dimensión tecnológica y la gestión; la dimensión social y cultural y la enseñanza en Arquitectura, Urbanismo y Diseño Industrial, sustentados en las líneas prioritarias de investigación definidas epistemológicamente en el Consejo Asesor de Ciencia y Tecnología de esta Universidad Nacional de Córdoba. Con el objetivo de afianzar continuidad, formación y transferencia de métodos, metodología y recursos se incorporó becarios y doctorandos de los Institutos de investigación. La Comisión Honoraria la integraron las tres Secretarias de Investigación de la Facultad, arquitectas Marta Polo, quien fundó y María del Carmen Franchello y Nora Gutiérrez Crespo quienes continuaron la tradición de la buena práctica del debate en la cotidianeidad de la propia Facultad. Los textos que conforman las VII Jornadas son los avances y resultados de las investigaciones realizadas en el bienio 2016-2018.Fil: Novello, María Alejandra. Universidad Nacional de Córdoba. Facultad de Arquitectura, Urbanismo y Diseño; ArgentinaFil: Repiso, Luciana. Universidad Nacional de Córdoba. Facultad de Arquitectura, Urbanismo y Diseño; ArgentinaFil: Mir, Guillermo. Universidad Nacional de Córdoba. Facultad de Arquitectura, Urbanismo y Diseño; ArgentinaFil: Brizuela, Natalia. Universidad Nacional de Córdoba. Facultad de Arquitectura, Urbanismo y Diseño; ArgentinaFil: Herrera, Fernanda. Universidad Nacional de Córdoba. Facultad de Arquitectura, Urbanismo y Diseño; ArgentinaFil: Períes, Lucas. Universidad Nacional de Córdoba. Facultad de Arquitectura, Urbanismo y Diseño; ArgentinaFil: Romo, Claudia. Universidad Nacional de Córdoba. Facultad de Arquitectura, Urbanismo y Diseño; ArgentinaFil: Gordillo, Natalia. Universidad Nacional de Córdoba. Facultad de Arquitectura, Urbanismo y Diseño; ArgentinaFil: Andrade, Elena Beatriz. Universidad Nacional de Córdoba. Facultad de Arquitectura, Urbanismo y Diseño; Argentin

Oxidative stress, antioxidants and intestinal calcium absorption

The disequilibrium between the production of reactive oxygen (ROS) and nitrogen (RNS) species and their elimination by protective mechanisms leads to oxidative stress. Mitochondria are the main source of ROS as by-products of electron transport chain. Most of the time the intestine responds adequately against the oxidative stress, but with aging or under conditions that exacerbate the ROS and/or RNS production, the defenses are not enough and contribute to developing intestinal pathologies. The endogenous antioxidant defense system in gut includes glutathione (GSH) and GSH-dependent enzymes as major components. When the ROS and/or RNS production is exacerbated, oxidative stress occurs and the intestinal Ca2+ absorption is inhibited. GSH depleting drugs such as DLbuthionine-S,R-sulfoximine, menadione and sodium deoxycholate inhibit the Ca2+ transport from lumen to blood by alteration in the protein expression and/or activity of molecules involved in the Ca2+ transcellular and paracellular pathways through mechanisms of oxidative stress, apoptosis and/or autophagy. Quercetin, melatonin, lithocholic and ursodeoxycholic acids block the effect of those drugs in experimental animals by their antioxidant, anti-apoptotic and/or anti-autophagic properties. Therefore, they may become drugs of choice for treatment of deteriorated intestinal Ca2+ absorption under oxidant conditions such as aging, diabetes, gut inflammation and other intestinal disorders.Fil: Díaz de Barboza, Gabriela Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Guizzardi, Solange Natali. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Moine, Luciana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Tolosa, Nori Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentin

Association of cellular and molecular alterations in Leydig cells with apoptotic changes in germ cells from testes of Graomys griseoflavus × Graomys centralis male hybrids

Spermatogenesis is disrupted in Graomys griseoflavus × Graomys centralis male hybrids. This study was aimed to determine whether morphological alterations in Leydig cells from hybrids accompany the arrest of spermatogenesis and cell death of germ cells and whether apoptotic pathways are also involved in the response of these interstitial cells. We used three groups of 1-, 2- and 3-month-old male animals: (1) G. centralis, (2) G. griseoflavus and (3) hybrids obtained by crossing G. griseoflavus females with G. centralis males. Testicular ultrastructure was analyzed by transmission electron microscopy. TUNEL was studied using an in situ cell death detection kit and the expression of apoptotic molecules by immunohistochemistry. The data confirmed arrest of spermatogenesis and intense apoptotic processes of germ cells in hybrids. These animals also showed ultrastructural alterations in the Leydig cells. Fas, FasL and calbindin D28k overexpression without an increase in DNA fragmentation was detected in the Leydig cells from hybrids. In conclusion, the sterility of Graomys hybrids occurs with ultrastructural changes in germ and Leydig cells. The enhancement of Fas and FasL is not associated with cell death in the Leydig cells. Probably the apoptosis in these interstitial cells is inhibited by the high expression of the antiapoptotic molecule calbindin D28k.Fil: Díaz de Barboza, Gabriela. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas; ArgentinaFil: Rodriguez, Valeria Andrea. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas; ArgentinaFil: Ponce, Rubén Hugo. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas; ArgentinaFil: Theiler, Gerardo. Universidad Nacional de Cordoba. Facultad de Odontologia; ArgentinaFil: Maldonado, Cristina Alicia. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas; ArgentinaFil: Tolosa, Nori Graciela. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Instituto de Investigaciones en Ciencias de la Salud; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas; Argentin

Glutamine protects both transcellular and paracellular pathways of chick intestinal calcium absorption under oxidant conditions

Glutamine (GLN) avoids the inhibition of the intestinal Ca2+ absorption caused by menadione (MEN) through oxidative stress. The purpose of this study was to elucidate whether molecules of transcellular and/or paracellular pathways of intestinal Ca2+ absorption are involved in the GLN action and underlying mechanisms. One-month old chicks were divided in four groups: 1) controls, 2) MEN treated, 3) GLN treated and 4) GLN + MEN treated. The morphology of intestinal villi, the intestinal Ca2+ absorption and the molecules involved in the transcellular and paracellular pathways were analyzed. Markers of autophagy and inflammation were also evaluated. The data demonstrated that GLN protected both transcellular and paracellular pathways. GLN avoided morphological changes in the intestine caused by MEN. GLN protected the gene expression of transporters involved in the transcellular pathway and the gene and protein expression of molecules belonging to the paracellular pathways altered by MEN. GLN increased the LC3-II protein expression and the number of acidic vesicular organelles, markers of autophagy, and blocked an increase in the NFkB protein expression in the nuclei and in the IL-6 gene expression caused by MEN. In conclusion, GLN protects both transcellular and paracellular pathways of intestinal Ca2+ absorption by increasing autophagy and blocking inflammation.Fil: Moine, Luciana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Perez, Adriana del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Maldonado, Cristina Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Tolosa, Nori Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Díaz de Barboza, Gabriela Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentin

Glutamine protects intestinal calcium absorption against oxidative stress and apoptosis

The aim of this study was to investigate whether glutamine (GLN) could block the inhibition of the intestinal Ca2+ absorption caused by menadione (MEN), and elucidate the underlying mechanisms. To do this, one-month old chicks were divided in four groups: 1) controls, 2) MEN treated, 3) GLN treated and 4) GLN treated before or after MEN treatment. Intestinal Ca2+ absorption as well as protein expression of molecules involved in the transcellular Ca2+ pathway were determined. Glutathione (GSH) and superoxide anion and activity of enzymes of the antioxidant system were evaluated. Apoptosis was measured by the TUNEL technique, the expression of FAS and FASL and the caspase-3 activity. A previous dose of 0.5 g GLN/kg of b.w. was necessary to show its protector effect and a dose of 1 g/kg of b.w. could restore the intestinal Ca2+ absorption after MEN treatment. GLN alone did not modify the protein expression of calbindin D28k and plasma membrane Ca2+-ATPase, but blocked the inhibitory effect of the quinone. GLN avoided changes in the intestinal redox state provoked by MEN such as a decrease in the GSH content, and increases in the superoxide anion and in the SOD and CAT activities. GLN abrogated apoptotic effects caused by MEN in intestinal mucosa, as indicated by the reduction of TUNEL (+) cells and the FAS/FASL/caspase-3 pathway. In conclusion, GLN could be an oral nutritional supplement to normalize the redox state and the proliferation/cell death ratio in the small intestine improving the intestinal Ca2+ absorption altered by oxidative stress.Fil: Moine, Luciana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Díaz de Barboza, Gabriela Edith. Universidad Nacional de Córdoba. Facultad de Medicina. Cátedra de Bioquímica y Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Pérez, Adriana del Carmen. Universidad Nacional de Córdoba. Facultad de Medicina. Cátedra de Bioquímica y Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; ArgentinaFil: Benedetto, Maria Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Química Biológica de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Centro de Investigaciones en Química Biológica de Córdoba; ArgentinaFil: Tolosa, Nori Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Ciencias de la Salud. Universidad Nacional de Córdoba. Instituto de Investigaciones en Ciencias de la Salud; Argentin