Neuroprotective effects of EpoL against oxidative stress induced by soluble oligomers of Aß peptide.

Erythropoietin is a glycoproteic hormone that regulates hematopoiesis by acting on its specific receptor (EpoR). The expression of EpoR in the central nervous system (CNS) suggests a role for this hormone in the brain. Recently, we developed a new Epo variant without hematopoietic activity called EpoL, which showed marked neuroprotective effects against oxidative stress in brain ischemia related models. In this study, we have evaluated the neuroprotective effects of EpoL against oxidative stress induced by chronic treatment with Aß. Our results show that EpoL was neuroprotective against Aß-induced toxicity by a mechanism that implicates EpoR, reduction in reactive oxygen species, and reduction in astrogliosis. Furthermore, EpoL treatment improved calcium handling and SV2 levels. Interestingly, the neuroprotective effect of EpoL against oxidative stress induced by chronic Aß treatment was achieved at a concentration 10 times lower than that of Epo. In conclusion, EpoL, a new variant of Epo without hematopoietic activity, is of potential interest for the treatment of diseases related to oxidative stress in the CNS such as Alzheimer disease.

El factor de crecimiento endotelial vascular (VEGF) y el fragmento N-terminal de la proteína relacionada con la parathormona (PTHrP) regulan la proliferación de células madre mesenquimales humanas / Vascular endothelial growth factor (VEGF) and the N-terminal portion of parathyroid hormone-related protein (PTHrP) regulate the proliferation of human mesenchymal stem cells

El tejido adiposo contiene un gran número de células madre mesenquimales (Adipose Stem Cells, ASCs) que residen en su estroma vascular. Aunque existe controversia acerca de la capacidad de generar tejido óseo de estas células in vivo, in vitro constituyen un buen modelo de diferenciación osteogénica debido a su semejanza fenotípica con las células estromales de la médula ósea (Bone Marrow Stromal Cells, BMSCs) en cultivo. La diferenciación de las poblaciones osteoprogenitoras de la médula ósea está intensamente regulada por factores locales, como el factor de crecimiento endotelial vascular (VEGF) y la proteína relacionada con la parathormona (PTHrP), que modulan la proliferación de estas poblaciones en distintos estadios de diferenciación. Tanto el VEGF como el fragmento N-terminal de la PTHrP ejercen efectos osteogénicos. En este estudio hipotetizamos que sus efectos sobre la proliferación celular de los osteoprogenitores son dependientes del estadio de diferenciación osteoblástica. Tras confirmar su capacidad de diferenciación in vitro por expresión génica de Runx2 y acumulación de calcio, se analizó la respuesta proliferativa a estímulos con VEGF o PTHrP(1-36) de ASCs sometidas o no a inducción osteogénica. VEGF pero no PTHrP(1-36) estimuló la capacidad proliferativa de las ASCs no inducidas mientras que PTHrP(1-36), pero no VEGF, estimuló la proliferación de las ASCs inducidas, corroborando el papel diferencial de estos factores de crecimiento en distintos estadios de diferenciación (AU)

Adipose tissue contains a large number of mesenchymal stem cells (ASCs) residing in their vascular stroma. Although there is controversy regarding the ability to generate bone tissue from these cells in vivo, the in vitro cells offer a good model of osteogenic differentiation due to its phenotypic similarity with the bone marrow stromal cells (BMSCs) in culture. The differentiation of osteo-progenitor populations of bone marrow is intensely regulated by local factors, such as vascular endothelial growth factor (VEGF) and parathyroid hormone-related protein (PTHrP), which modulate these populations' proliferation in different stages of differentiation. Both the VEGF and the N-terminal fragment of the PTHrP exert osteogenic effects. In this study, we posited that its effects on proliferation of osteo-progenitors are stage dependent of osteoblastic differentiation. After confirming its capacity to in vitro differentiation by Runx2 gene expression and accumulation of calcium, the proliferative response to stimuli was analyzed with VEGF or PTHrP (1-36) of ASCs submitted or not to osteogenic induction. VEGF, but not PTHrP (1- 36), stimulated the proliferative capacity of uninduced ASCs, whereas BMSCs, but not VEGF, stimulated the proliferation of induced ASCs, corroborating the differential role of this growth in different stages of differentiation (AU)

ConBr, A Lectin Purified from the Seeds of Canavalia brasiliensis, Protects Against Ischemia in Organotypic Culture of Rat Hippocampus: Potential Implication of Voltage-Gated Calcium Channels.

Lectins are proteins that bind cellular glycans and can modulate various neuronal functions. We have evaluated the neuroprotective effect of ConBr, a lectin purified from the seeds of Canavalia brasiliensis in a model of rat organotypic hippocampal cultures (OHCs) exposed to oxygen and glucose deprivation (OGD). OGD for 15 min followed by 24 h re-oxygenation significantly increased cell death, caused mitochondrial depolarization and increased reactive oxygen species (ROS) in CA1 region of OHCs. ConBr (0.1 µg/mL) added during the re-oxygenation period counteracted cell death, mitochondrial depolarization and overproduction of ROS induced by OGD. Moreover, ConBr restored the levels of Akt and ERK1 phosphorylation that were reduced by OGD. Modulation of intracellular Ca2+ by ConBr was evaluated in isolated hippocampal neurons loaded with the fluorescent calcium dye Fluo-4/AM. ConBr (0.1 and 1 µg/mL) reduced by 25-30 % the Ca2+ increment induced by 70 mM K+. A sub effective concentration of ConBr (0.01 µg/mL) together with a sub effective concentration of the L-type calcium channel antagonist nifedipine (0.3 µM) conferred a synergic neuroprotective effect in OHCs subjected to OGD. In conclusion, ConBr provides OHCs neuroprotection against OGD. The mechanism was not fully addressed but it may involve modulation of L-type voltage-gated Ca2+ channels by ConBr.

Subthreshold Concentrations of Melatonin and Galantamine Improves Pathological AD-Hallmarks in Hippocampal Organotypic Cultures.

Melatonin is a neurohormone whose levels are significantly reduced or absent in Alzheimer's disease (AD) patients. In these patients, acetylcholinesterase inhibitors (AChEI) are the major drug class used for their treatment; however, they present unwanted cholinergic side effects and have provided limited efficacy in clinic. Because combination therapy is being extensively used to treat different pathological diseases such as cancer or acquired immune deficiency syndrome, we posed this study to evaluate if melatonin in combination with an AChEI, galantamine, could provide beneficial properties in a novel in vitro model of AD. Thus, we subjected organotypic hippocampal cultures (OHCs) to subtoxic concentrations of ß-amyloid (0.5 µM ßA) plus okadaic acid (1 nM OA), for 4 days. This treatment increased by 95 % cell death, which was mainly apoptotic as shown by positive TUNEL staining. In addition, the combination of ßA/OA increased Thioflavin S aggregates, hyperphosphorylation of Tau, oxidative stress (increased DCFDA fluorescence), and neuroinflammation (increased IL-1ß and TNFα). Under these experimental conditions, melatonin (1-1000 nM) and galantamine (10-1000 nM), co-incubated with the toxic stimuli, caused a concentration-dependent neuroprotection; maximal neuroprotective effect was achieved at 1 µM of melatonin and galantamine. Most effective was the finding that combination of sub-effective concentrations of melatonin (1 nM) and galantamine (10 nM) provided a synergic anti-apoptotic effect and reduction of most of the AD-related pathological hallmarks observed in the ßA/OA model. Therefore, we suggest that supplementation of melatonin in combination with lower doses of AChEIs could be an interesting strategy for AD patients.

Small synthetic hyaluronan disaccharides afford neuroprotection in brain ischemia-related models.

High molecular weight (HMW) glycosaminoglycanes of the extracellular matrix have been implicated in tissue repair. The aim of this study was to evaluate if small synthetic hyaluronan disaccharides with different degrees of sulfation (methyl 2-acetamido-2-deoxy-3-O-(ß-d-glucopyranosyluronic acid)-O-sulfo-α-d-glucopyranoside, sodium salt (di0S), methyl 2-acetamido-2-deoxy-3-O-(ß-d-glucopyranosyluronic acid)-6-di-O-sulfo-α-d-glucopyranoside, disodium salt (di6S) and methyl 2-acetamido-2-deoxy-3-O-(ß-d-glucopyranosyluronic acid)-4,6-di-O-sulfo-α-d-glucopyranoside, trisodium salt (di4,6S)) could improve cell survival in in vitro and in vivo brain ischemia-related models. Rat hippocampal slices subjected to oxygen and glucose deprivation and a photothrombotic stroke model in mice were used. The three hyaluran disaccharides, incubated during the oxygen and glucose deprivation (15min) and re-oxygenation periods (120min), reduced cell death of hippocampal slices measured as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction, being the most potent di4,6S; in contrast, high molecular hyaluronan was ineffective. The protective actions of di4,6S against oxygen and glucose deprivation were related to activation of the PI3K/Akt survival pathway, reduction of p65 translocation to the nucleus, inhibition of inducible nitric oxide oxidase induction and reactive oxygen species production, and to an increase in glutathione levels. Administered 1h post-stroke, di4,6S reduced cerebral infarct size and improved motor activity in the beam walk test. In conclusion, di4,6S affords neuroprotection in in vitro and in vivo models of ischemic neuronal damage. Our results suggest that its neuroprotective effect could be exerted through its capability to reduce oxidative stress during ischemia. Its small molecular size makes it a more potential druggable drug to target the brain as compared with its HMW parent compound hyaluronan.

Biodegradability of meat industry wastes under anaerobic and aerobic conditions.

In this study the biodegradation kinetics and the different biologically degradable fractions (readily, slowly and inert fractions) of the organic wastes generated in a meat industry have been estimated under both anaerobic and aerobic conditions. Three of these could be degraded under both conditions, whereas one (pig/cow waste slurries) could only be aerobically degraded since the high ammonia concentration caused inhibition in anaerobic experiments. Mathematical models for anaerobic and aerobic degradations were used to estimate the readily (S(S)) and slowly (X) biodegradable fractions of the meat industry wastes. Using these models, a good agreement was observed between the calculated S(S) fractions for each waste under anaerobic and aerobic conditions, while the calculated X fractions in the aerobic tests were lower than in the anaerobic tests. The experiments, in combination with the modelling, showed that aerobic respirometric test may be used for predicting readily biodegradable fractions under both anaerobic and aerobic conditions provided that ammonia concentration is not significantly high. Thus, for complex organic wastes the length of experiments for estimating biodegradable fractions may be considerably reduced (in this case by 10-12 days).

Anaerobic co-digestion of winery wastewater.

The operational performance of anaerobic batch reactors treating winery wastewater (WW) combined with waste activated sludge (WAS) in different proportions was investigated under mesophilic conditions. In these experiments it was shown that for anaerobic digestion of WW alone, methane production rate was lower than the rates achieved when WW and WAS were treated together. When WW was mixed with WAS at a concentration of 50% WW resulted in the highest methane production rates. A simplified anaerobic model was used to determine the main kinetic parameters; maximum COD reduction rate (q(DA)) and maximum methane generation rate (k(max)). The maximum values of q(DA) and k(max) were 16.50 kgCOD COD(-1) d(-1) and 14.34 kgCOD kgCOD(-1) d(-1), respectively.

Re-use of winery wastewaters for biological nutrient removal.

The aim of this study was to evaluate the feasibility of the re-use of the winery wastewater to enhance the biological nutrient removal (BNR) process. In batch experiments it was observed that the addition of winery wastewater mainly enhanced the nitrogen removal process because of the high denitrification potential (DNP), of about 130 mg N/g COD, of the contained substrates. This value is very similar to that obtained by using pure organic substrates such as acetate. The addition of winery wastewater did not significantly affect either phosphorus or COD removal processes. Based on the experimental results obtained, the optimum dosage to remove each mg of N-NO3 was determined, being a value of 6.7 mg COD/mg N-NO3. Because of the good properties of the winery wastewater to enhance the nitrogen removal, the viability of its continuous addition in an activated sludge pilot-scale plant for BNR was studied. Dosing the winery wastewater to the pilot plant a significant increase in the nitrogen removal was detected, from 58 to 75%. The COD removal was slightly increased, from 89 to 95%, and the phosphorus removal remained constant.

Guía para la solicitud de Acreditación de una actividad de Formación Continuada en Alergología / Guidelines for requesting accreditation of an ongoing training activity in Allergology

En una medicina sometida a constantes cambios, la formación médica continuada (FMC) constituye una herramienta fundamental para el profesional de la medicina. En España, durante las últimas décadas la FMC ha sido preocupación constante de múltiples colectivos, sin embargo, no ha sido hasta principios de los 90 cuando han surgido las primeras iniciativas de acreditación. La FMC es una preocupación ampliamente asumida por los profesionales sanitarios, al tiempo que un compromiso y una obligación de la Administración. Recientemente, con el fin de regular la Acreditación de este tipo de actividades en el ámbito de todo el Estado Español, se ha creado la Comisión de Formación Continuada del Sistema Nacional de Salud, mediante la utilización de la figura de Conferencia Sectorial, prevista en los artículos 5 y 8 de la Ley de Régimen Jurídico de las Administraciones Públicas y del Procedimiento Administrativo Común, como Superior Órgano Técnico en la materia. En el presente manuscrito, se describen los pasos que se deben dar para solicitar la acreditación de una actividad de Formación Médica Continuada en Alergología, explicando los diferentes ítems del "modelo oficial de solicitud", perfilando los fundamentos sobre los cuales se valoran las actividades a efectos de acreditación, con el fin de garantizar que la actividad formativa cumple los más altos índices de calidad para que así se consigan los objetivos. Finalmente, se hace una sucinta revisión de la FMC en el mundo (AU)