Ginkgo Biloba Extract Ameliorates Oxidative Phosphorylation Performance and Rescues Aβ-Induced Failure

Energy deficiency and mitochondrial failure have been recognized as a prominent, early event in Alzheimer's disease (AD). Recently, we demonstrated that chronic exposure to amyloid-beta (Abeta) in human neuroblastoma cells over-expressing human wild-type amyloid precursor protein (APP) resulted in (i) activity changes of complexes III and IV of the oxidative phosphorylation system (OXPHOS) and in (ii) a drop of ATP levels which may finally instigate loss of synapses and neuronal cell death in AD. Therefore, the aim of the present study was to investigate whether standardized Ginkgo biloba extract LI 1370 (GBE) is able to rescue Abeta-induced defects in energy metabolism

Análisis de las Estrategias Metodológicas implementadas por el docente en el desarrollo del proceso de enseñanza- aprendizaje en la disciplina de Geografía e Historia de Nicaragua y su Didáctica en los alumnos/as de Primer año “B” del turno regular de Formación Inicial Docente en la Escuela Normal Central de Managua Alesio Blandón Juárez durante el I semestre del Curso Escolar 2016

El presente trabajo de investigación tiene como finalidad analizar la efectividad que tienen las Estrategias Metodológicas implementadas por el docente en el desarrollo del proceso de enseñanza- aprendizaje en la disciplina de Geografía de Nicaragua y su Didáctica en los alumnos/as de Primer año “B” del turno regular de Formación Inicial Docente en la Escuela Normal Central de Managua Alesio Blandón Juárez durante el I semestre del Curso Escolar 2016. Dicho trabajo de investigación tiene un enfoque naturista o cualitativo, es una vía de transformación social, a través de la cual el ser humano descubre la realidad que le rodea, determina los medios y procedimientos para actuar sobre ella y transformarla de acuerdo a una intensión social. Los procesos de investigación cualitativa, tienen como finalidad primordial la generación y construcción de conocimientos que contribuyen al desarrollo social y personal de cada uno de los miembros de una comunidad. La fase de recolección de los datos de la investigación desarrollada, se realizó de dos formas: una información que se recogió mediante la observación directa del comportamiento de los informantes claves y una información que se obtuvo mediante la interrogación de algunos informantes claves. Para ello, primeramente el investigador realizo una inmersión en el campo de trabajo, con el propósito de identificar los lugares adecuados para recoger y producir la información necesaria y requerid

Stimulation of neurogenesis and synaptogenesis by bilobalide and quercetin via common final pathway in hippocampal neurons

Loss of synapses has been correlated with dementia in Alzheimer's disease (AD) as an early event during the disease progression. Hence, synaptogenesis and neurogenesis in adulthood could serve as a therapeutic target for the prevention and treatment of AD. Recently, we have demonstrated enhanced hippocampal neurogenesis by oral administration of Ginkgo biloba extract (EGb 761) to a mouse model of AD. This study aims to identify the constituents that contribute to EGb 761-induced neurogenesis. Among the constituents tested, bilobalide and quercetin significantly increased cell proliferation in the hippocampal neurons in a dose-dependent manner. Bilobalide and quercetin also enhanced phosphorylation of cyclic-AMP Response Element Binding Protein (CREB) in these cells, and elevated the levels of pCREB and, brain-derived neurotrophic factor in mice brain. Immunofluorescence staining of synaptic markers shows remarkable dendritic processes in hippocampal neurons treated with either quercetin or bilobalide. Furthermore, both constituents restored amyloid-β oligomers (also known as ADDL)-induced synaptic loss and phosphorylation of CREB. The present findings suggest that enhanced neurogenesis and synaptogenesis by bilobalide and quercetin may share a common final signaling pathway mediated by phosphorylation of CREB. Despite a recent report showing that EGb 761 was insufficient in prevent dementia, its constituents still warrant future investigation. © 2009-IOS Press and the authors. All rights reserved.link_to_subscribed_fulltex

Genetic variants of methionine metabolism and X-ALD phenotype generation: results of a new study sample

X-linked adrenoleukodystrophy (X-ALD) is the most common inherited leukodystrophy. Nevertheless, no genotype-phenotype correlation has been established so far. Unidentified modifier genes or other cofactors are suspected to modulate phenotype and prognosis. We recently described polymorphisms of methionine metabolism as possible disease modifiers in X-ALD. To retest these findings, we analyzed 172 new DNA samples of X-ALD patients from different populations (France, Germany, USA, China) by genotyping eight genetic variants of methionine metabolism, including DHFR c.594+59del19bp, CBS c.844_855ins68, MTR c.2756A>G, MTHFR c.677C>T and c.1298A>C, MTRR c.60A>G, RFC1 c.80G>A, and Tc2 c.776C>G. We compared three X-ALD phenotypes: childhood-onset cerebral demyelinating inflammatory type (CCALD; n = 82), adulthood onset with focal cerebral demyelination (ACALD; n = 38), and adulthood onset without cerebral demyelination (AMN; n = 52). The association of genotypes and phenotypes was analyzed with univariate two-sided Pearson's chi(2). In the comparison between AMN and CCALD, the G allele of Tc2 c.776C>G was associated with X-ALD phenotypes (chi(2) = 6.1; P = 0.048). The prevalence of the GG genotype of Tc2 c.776C>G was higher in patients with CNS demyelination compared to those without CNS demyelination (chi(2) = 4.42; P = 0.036). The GG genotype was also more frequent in CCALD compared to AMN (chi(2) = 4.7; P = 0.031). The other polymorphisms did not show any significant associations in this study sample. Whereas the influence of other polymorphisms of methionine metabolism was not confirmed, the present study supports the previously made observation that the Tc2 genotype contributes to X-ALD phenotype generation