Regulator of calcineurin 1 (Rcan1) has a protective role in brain ischemia/reperfusion injury

<p>Abstract</p> <p>Background</p> <p>An increase in intracellular calcium concentration [Ca²⁺]_iis one of the first events to take place after brain ischemia. A key [Ca²⁺]_i-regulated signaling molecule is the phosphatase calcineurin (CN), which plays important roles in the modulation of inflammatory cascades. Here, we have analyzed the role of endogenous regulator of CN 1 (Rcan1) in response to experimental ischemic stroke induced by middle cerebral artery occlusion.</p> <p>Methods</p> <p>Animals were subjected to focal cerebral ischemia with reperfusion. To assess the role of Rcan1 after stroke, we measured infarct volume after 48 h of reperfusion in <it>Rcan1 </it>knockout (KO) and wild-type (WT) mice. <it>In vitro </it>studies were performed in astrocyte-enriched cortical primary cultures subjected to 3% oxygen (hypoxia) and glucose deprivation (HGD). Adenoviral vectors were used to analyze the effect of overexpression of Rcan1-4 protein. Protein expression was examined by immunohistochemistry and immunoblotting and expression of mRNA by quantitative real-time Reverse-Transcription Polymerase Chain Reaction (real time qRT-PCR).</p> <p>Results</p> <p>Brain ischemia/reperfusion (I/R) injury <it>in vivo </it>increased mRNA and protein expression of the calcium-inducible Rcan1 isoform (Rcan1-4). I/R-inducible expression of Rcan1 protein occurred mainly in astroglial cells, and in an <it>in vitro </it>model of ischemia, HGD treatment of primary murine astrocyte cultures induced Rcan1-4 mRNA and protein expression. Exogenous Rcan1-4 overexpression inhibited production of the inflammatory marker cyclo-oxygenase 2. Mice lacking Rcan1 had higher expression of inflammation associated genes, resulting in larger infarct volumes.</p> <p>Conclusions</p> <p>Our results support a protective role for Rcan1 during the inflammatory response to stroke, and underline the importance of the glial compartment in the inflammatory reaction that takes place after ischemia. Improved understanding of non-neuronal mechanisms in ischemic injury promises novel approaches to the treatment of acute ischemic stroke.</p

Robust and accurate modeling approaches for migraine Per-Patient prediction from ambulatory data

Migraine is one of the most wide-spread neurological disorders, and its medical treatment represents a high percentage of the costs of health systems. In some patients, characteristic symptoms that precede the headache appear. However, they are nonspecific, and their prediction horizon is unknown and pretty variable; hence, these symptoms are almost useless for prediction, and they are not useful to advance the intake of drugs to be effective and neutralize the pain. To solve this problem, this paper sets up a realistic monitoring scenario where hemodynamic variables from real patients are monitored in ambulatory conditions with a wireless body sensor network (WBSN). The acquired data are used to evaluate the predictive capabilities and robustness against noise and failures in sensors of several modeling approaches. The obtained results encourage the development of per-patient models based on state-space models (N4SID) that are capable of providing average forecast windows of 47 min and a low rate of false positives

Rosiglitazone-induced CD36 up-regulation resolves inflammation by PPARγ and 5-LO-dependent pathways.

PPARγ-achieved neuroprotection in experimental stroke has been explained by the inhibition of inflammatory genes, an action in which 5-LO, Alox5, is involved. In addition, PPARγ is known to promote the expression of CD36, a scavenger receptor that binds lipoproteins and mediates bacterial recognition and also phagocytosis. As phagocytic clearance of neutrophils is a requisite for resolution of the inflammatory response, PPARγ-induced CD36 expression might help to limit inflammatory tissue injury in stroke, an effect in which 5-LO might also be involved. Homogenates, sections, and cellular suspensions were prepared from brains of WT and Alox5(-/-) mice exposed to distal pMCAO. BMMs were obtained from Lys-M Cre(+) PPARγ(f/f) and Lys-M Cre(-) PPARγ(f/f) mice. Stereological counting of double-immunofluorescence-labeled brain sections and FACS analysis of cell suspensions was performed. In vivo and in vitro phagocytosis of neutrophils by microglia/macrophages was analyzed. PPARγ activation with RSG induced CD36 expression in resident microglia. This process was mediated by the 5-LO gene, which is induced in neurons by PPARγ activation and at least by one of its products--LXA4--which induced CD36 independently of PPARγ. Moreover, CD36 expression helped resolution of inflammation through phagocytosis, concomitantly to neuroprotection. Based on these findings, in addition to a direct modulation by PPARγ, we propose in brain a paracrine model by which products generated by neuronal 5-LO, such as LXA4, increase the microglial expression of CD36 and promote tissue repair in pathologies with an inflammatory component, such as stroke.This work was supported by grants from the Spanish Ministry of Economy and Competitiveness CSD2010-00045 (to M.A.M.) SAF2009-08145 and SAF2012-33216 (to M.A.M.), SAF2011-23354 (toI.L.), SAF2009-07466 and SAF2012-31483 (to M.R.), from Fondo Europeo de Desarrollo Regional (FEDER) “Instituto de Salud Carlos III” RETICS RD12/0014/0003 (to I.L. and from the local govern-ment of Madrid S2010/BMD-2336 (to M.A.M.) and S2010/BMD-2349 (to I.L.). I.B. and M.I.C. are fellows of the Spanish Ministry ofEconomy and Competitiveness. The authors thank Tamara Atanesand Roberto Cañadas for their technical assistance.S

Aplicació Mascoteando, puedo entrar?

Aquest projecte sorgeix de la necessitats de molts propietaris de mascotes, principalment gossos, que en algun moment han volgut sortir a dinar, de compres o a donar un passeig amb els seus gossos i no sabien on anar tranquil·lament sense entrar a algun espai i li diguessin que no s'admetien gossos. Per aquest motiu, vaig decidir posar solució a aquestes situacions creant una aplicació per a tothom que vulgui anar acompanyat dels seus gossos a qualsevol lloc, on poder consultar els locals, establiments i espais diversos que tinguessin més a prop per poder anar sense cap preocupació. A més, que els mateixos usuaris tinguessin la possibilitat de valorar les seves experiències dins d'aquests espais o poder compartir-ne de nous per facilitar aquesta informació a la resta d'usuaris. Amb l'aplicació Mascoteando, no només es crearà una xarxa d'informació entre propietaris de gossos, sinó que es crearà una comunitat de gossos on els usuaris registrats no seran persones, sinó que seran els propis gossos amb la seva imatge, la seva raça, la seva mida, el seu propietari... tot un perfil sencer pels nostres gossos. Això ens podrà permetre saber quin tipus de gos a entrat a cada establiment i les possibilitats d'accedir amb gossos més grans o més petits en funció de cadascun i les seves aportacions.Este proyecto surge de la necesidades de muchos propietarios de mascotas, principalmente perros, que en algún momento han querido salir a comer, de compras o a dar un paseo con sus perros y no sabían donde ir tranquilamente sin entrar a algún espacio y le dijeran que no se admitían perros. Por este motivo, decidí poner solución a estas situaciones creando una aplicación para todo el mundo que quiera ir acompañado de sus perros a cualquier lugar, donde poder consultar los locales, establecimientos y espacios diversos que tuvieran más cerca para poder ir sin ninguna preocupación. Además, que los mismos usuarios tuvieran la posibilidad de valorar sus experiencias dentro de estos espacios o poder compartir de nuevos para facilitar esta información al resto de usuarios. Con la aplicación Mascoteando, no sólo se creará una red de información entre propietarios de perros, sino que se creará una comunidad de perros donde los usuarios registrados no serán personas, sino que serán los propios perros con su imagen, su raza, su medida, su propietario... todo un perfil entero por nuestros perros. Esto nos podrá permitir saber qué tipo de perro a entrado a cada establecimiento y las posibilidades de acceder con perros más grandes o más pequeños en función de cada uno y sus aportaciones.This project arises from the needs of many pet owners, specially dog owners, who at some point have wanted to go out for lunch, go shopping or take a walk with their dogs and didn¿t know where to go without the fear of going somewhere and being told that their dog is not allowed there. That's why I decided to avoid these situations creating an application for everyone who wants to go anywhere with their dog, where users can look up what store, establishments and others spaces near them they can visit without worrying about their pets being a problem. In addition, the users will have the possibility to rate their experiences within these spaces or add new ones to share the information with the rest of users. That's why I decided to avoid these situations creating an application for everyone who wants to go anywhere with their dog, where users can look up what store, establishments and others spaces near them they can visit without worrying about their pets being a problem. In addition, the users will have the possibility to rate their experiences within these spaces or add new ones to share the information with the rest of users

Combinación farmacológica y neuroprotección en isquemia cerebral focal y en rodajas de hipocampo de rata

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid. Facultad de Medicina. Departamento de Farmacología y Terapéutica. Fecha de lectura: 2 de Noviembre de 200

Neuroprotection afforded by nicotine against oxygen and glucose deprivation in hippocampal slices is lost in α7 nicotinic receptor knockout mice

Although α7-receptors are considered the main target for neuroprotection, other receptor subtypes (α4β2 or α3β4) have also been implicated. Hence, we have used α7-transgenic mice, to study the hypothesis that α7-receptors play a dominant role in mediating neuroprotection in an in vitro model of ischemia. We have used rat and mouse hippocampal slices to establish the model of nicotinic neuroprotection against oxygen and glucose deprivation (OGD). Neuronal damage caused by OGD during 1 h plus 3 h re-oxygenation, was quantified by measuring lactate dehydrogenase (LDH) release from hippocampal slices. In rat hippocampal slices, OGD increased over twofold basal LDH release. Such increase was reduced when treated with 10-100 μM nicotine; maximal protection afforded by nicotine amounted to 46%. This neuroprotection was antagonized by the non-selective nicotinic receptor for acetylcholine (nAChR) blocker mecamylamine (10 μM). In hippocampal slices from wild-type control mice, nicotine (100 μM) decreased by 54.4% LDH release evoked by OGD plus re-oxygenation. In contrast, nicotine failed to exert neuroprotection in α7 knockout mice. This finding reinforces the view that the hippocampal neuroprotective effects of nicotine are predominantly linked to α7 receptors. © 2007 IBRO.We acknowledge the financial support of Fundación La Caixa, Barcelona, and Comunidad Autónoma de Madrid to A.G.G. and from Ministerio de Ciencia y Tecnología SAF2006-08540 to M.G.L.Peer Reviewe

Galantamine postischemia provides neuroprotection and memory recovery against transient global cerebral ischemia in gerbils

Galantamine, currently used in Alzheimer's patients, has shown neuroprotection in hippocampal slices subjected to oxygen-glucose deprivation. Here, we present an in vivo study to evaluate the potential neuroprotective effects of galantamine in a transient global cerebral ischemia model in gerbils. Three treatment protocols were used. In the pretreatment protocol, gerbils were treated before ischemia and for 3 consecutive days thereafter. Eight groups of animals were included: sham operation plus placebo, 10 mg/kg mecamylamine and 10 mg/kg galantamine, respectively; and ischemia plus placebo, 10 mg/kg mecamylamine, 1 mg/kg galantamine, and 10 mg/kg galantamine and 10 mg/kg mecamylamine plus galantamine, respectively. Postischemia protocols included three groups of animals: sham operation, ischemia plus placebo, and ischemia plus 10 mg/kg galantamine; substances were administered 3 or 6 h after ischemia and for 2 consecutive days thereafter. Pyramidal neurons surviving in the cornus ammonis 1 region of the hippocampus were evaluated 72 h after reperfusion, terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) histochemistry, caspase-3 and superoxide dismutase (SOD)-2 immunohistochemistries, and Western blottings were performed, and object placement tests were carried out. Galantamine significantly increased the number of living pyramidal neurons after ischemia-reperfusion injury. Galantamine significantly reduced TUNEL, active caspase-3, and SOD-2 immunoreactivity. The nicotinic antagonist mecamylamine blocked the protective effects of galantamine. The neuroprotective effects of galantamine were preserved even when first administered at 3 h postischemia. These results correlated with the performance in the object placement test. This study shows that galantamine provides in vivo neuroprotection and memory recovery against global cerebral ischemia, even when administration begins 3 h postischemia. Copyright © 2007 by The American Society for Pharmacology and Experimental Therapeutics.This study was supported in part by the Dirección General de Investigación Científica y Técnica (Grant SAF2006-08540 to M.G.L.), by the Dirección General de Investigación Científica y Técnica (Grant SAF2006-03589), by the Spanish Ministry of Health (Instituto de Salud Carlos III) (Grant RETICSRD06/0026), and by Comunidad Autónoma de Madrid (Grant SAL2006/0275).Peer Reviewe

Kidins220/ARMS downregulation by excitotoxic activation of NMDARs reveals its involvement in neuronal survival and death pathways

12 pages, 7 figures.Functional and protein interactions between the N-methyl-D-aspartate type of glutamate receptor (NMDAR) and neurotrophin or ephrin receptors play essential roles in neuronal survival and differentiation. A shared downstream effector for neurotrophin- and ephrin-receptor signaling is kinase D-interacting substrate of 220 kDa (Kidins220), also known as ankyrin repeat-rich membrane spanning (ARMS). Because this molecule is obligatory for neurotrophin-induced differentiation, we investigated whether Kidins220/ARMS and NMDAR functions were related. Here, we identify an association between these proteins and discover that excitotoxicity, a specific form of neuronal death induced by NMDAR overstimulation, dramatically decreases Kidins220/ARMS levels in cortical neurons and in a model of cerebral ischemia. Kidins220/ARMS downregulation is triggered by overactivation of NMDARs containing NR2B subunits and subsequent Ca2+ influx, and involves a dual mechanism: rapid cleavage by the Ca2+-dependent protease calpain and calpain-independent silencing of Kidins220/Arms gene transcription. Additionally, Kidins220/ARMS knockdown decreases ERK activation and basal neuronal viability, and enhances neuronal death under excitotoxic conditions. Our results demonstrate Kidins220/ARMS participation in neuronal life and death pathways, and constitute the first report of its regulation under pathological conditions.This work was supported by grants BFU2007-67695 from `Ministerio de Ciencia e Innovación and `Fundación Mutua Madrileña' to M.D.-G.; and SAF2008-01951 from `Ministerio de Ciencia e Innovación', CAM S-SAL-0202-2006-01 from `Comunidad de Madrid' and CIBERNED from `Instituto de Salud Carlos III' to T.I. C.L.-M. and S.G. were recipients of a research contract and a predoctoral fellowship, respectively, funded by `Comunidad de Madrid'.Peer reviewe