Search results for "nervous system"
showing 10 items of 3271 documents
La alteración de la mielina en la enfermedad de Alexander
2018
Resumen: Introducción: La enfermedad de Alexander (AxD) es una leucodistrofia. Su base patológica, junto a la pérdida de mielina, es la aparición de los cuerpos de Rosenthal, que son inclusiones citoplasmáticas en células astrocitarias. Mutaciones en el gen que codifica la GFAP se han identificado como una base genética para AxD. Sin embargo, no se conoce el mecanismo por el cual estas variantes producen la enfermedad. Desarrollo: La hipótesis más extendida es que AxD se desarrolla por un mecanismo por ganancia de función debido al incremento de GFAP. Sin embargo, este mecanismo no explica la pérdida mielínica, dado que los modelos experimentales que expresan GFAP normal o mutada no generan…
Functions of histone modifications and histone modifiers in Schwann cells.
2019
Schwann cells (SCs) are the main glial cells present in the peripheral nervous system (PNS). Their primary functions are to insulate peripheral axons to protect them from the environment and to enable fast conduction of electric signals along big caliber axons by enwrapping them in a thick myelin sheath rich in lipids. In addition, SCs have the peculiar ability to foster axonal regrowth after a lesion by demyelinating and converting into repair cells that secrete neurotrophic factors and guide axons back to their former target to finally remyelinate regenerated axons. The different steps of SC development and their role in the maintenance of PNS integrity and regeneration after lesion are c…
Exposure to a Highly Caloric Palatable Diet During Pregestational and Gestational Periods Affects Hypothalamic and Hippocampal Endocannabinoid Levels…
2016
Journal Article; Exposure to unbalanced diets during pre-gestational and gestational periods may result in long-term alterations in metabolism and behavior. The contribution of the endocannabinoid system to these long-term adaptive responses is unknown. In the present study, we investigated the impact of female rat exposure to a hypercaloric-hypoproteic palatable diet during pre-gestational, gestational and lactational periods on the development of male offspring. In addition, the hypothalamic and hippocampal endocannabinoid contents at birth and the behavioral performance in adulthood were investigated. Exposure to a palatable diet resulted in low weight offspring who exhibited low hypotha…
AMPA receptor complex constituents: Control of receptor assembly, membrane trafficking and subcellular localization
2018
Fast excitatory transmission at synapses of the central nervous system is mainly mediated by AMPA receptors (AMPARs). Synaptic AMPAR number and function correlates with synaptic strength. AMPARs are thus key proteins of activity-dependent plasticity in neuronal communication. Up- or down-regulation of synaptic AMPAR number is a tightly controlled dynamic process that involves export of receptors from the endoplasmic reticulum (ER) and Golgi apparatus, exocytosis and endocytosis as well as lateral diffusion of the receptors in the cell membrane. The four AMPAR subunits are embedded into a dynamic network of more than 30 interacting proteins. Many of these proteins are known to modulate recep…
Prox1 Is Required for Oligodendrocyte Cell Identity in Adult Neural Stem Cells of the Subventricular Zone
2016
Abstract Adult neural stem cells with the ability to generate neurons and glia cells are active throughout life in both the dentate gyrus (DG) and the subventricular zone (SVZ). Differentiation of adult neural stem cells is induced by cell fate determinants like the transcription factor Prox1. Evidence has been provided for a function of Prox1 as an inducer of neuronal differentiation within the DG. We now show that within the SVZ Prox1 induces differentiation into oligodendrocytes. Moreover, we find that loss of Prox1 expression in vivo reduces cell migration into the corpus callosum, where the few Prox1 deficient SVZ-derived remaining cells fail to differentiate into oligodendrocytes. Thu…
Role of IL-17-producing lymphocytes in severity of multiple sclerosis upon natalizumab treatment.
2016
Objective: Natalizumab is known to prevent T-helper cells entering the central nervous system (CNS). We hypothesize that more pathogenic T-helper cells are present outside the CNS and a possible relationship to disease severity. Methods: Characterization and enrichment of human CD4+IL-17+ cells were performed ex vivo using peripheral blood mononuclear cells from natalizumab-treated relapsing-remitting multiple sclerosis (RRMS) patients ( n = 33), untreated RRMS patients ( n = 13), and healthy controls ( n = 33). Magnetic resonance imaging (MRI) scans were performed routinely for patients. Results: Lymphocytes were elevated in peripheral blood of natalizumab-treated patients compared to untr…
Human hippocampal neurogenesis drops sharply in children to undetectable levels in adults.
2018
New neurons continue to be generated in the subgranular zone of the dentate gyrus of the adult mammalian hippocampus(1-5). This process has been linked to learning and memory, stress and exercise, and is thought to be altered in neurological disease(6-10). In humans, some studies have suggested that hundreds of new neurons are added to the adult dentate gyrus every day(11), whereas other studies find many fewer putative new neurons(12-14). Despite these discrepancies, it is generally believed that the adult human hippocampus continues to generate new neurons. Here we show that a defined population of progenitor cells does not coalesce in the subgranular zone during human fetal or postnatal …
Rescuing Over-activated Microglia Restores Cognitive Performance in Juvenile Animals of the Dp(16) Mouse Model of Down Syndrome.
2020
Microglia are brain-resident immune cells and regulate mechanisms essential for cognitive functions. Down syndrome (DS), the most frequent cause of genetic intellectual disability, is caused by a supernumerary chromosome 21, containing also genes related to the immune system. In the hippocampus of the Dp(16) mouse model of DS and DS individuals, we found activated microglia, as assessed by their morphology; activation markers; and, for DS mice, electrophysiological profile. Accordingly, we found increased pro-inflammatory cytokine levels and altered interferon signaling in Dp(16) hippocampi. DS mice also showed decreased spine density and activity of hippocampal neurons and hippocampus-depe…
Cortical network fingerprints predict deep brain stimulation outcome in dystonia.
2018
AbstractBackgroundDeep brain stimulation (DBS) is an effective evidence-based therapy for dystonia. However, no unequivocal predictors of therapy responses exist. We investigate whether patients optimally responding to DBS present distinct brain network organization and structural patterns.MethodsBased on a German multicentre cohort of eighty-two dystonia patients with segmental and generalized dystonia, who received DBS implantation in the globus pallidus internus patients were classified based on the clinical response 36 months after DBS, as superior-outcome group or moderate-outcome group, as above or below 70% motor improvement, respectively. Fifty-one patients met MRI-quality and treat…
Prediction of unfavorable outcomes in West Nile virus neuroinvasive infection - Result of a multinational ID-IRI study
2019
Background: WNV causes 1.4% of all central nervous system infections and is the most common cause of epidemic neuro-invasive disease in humans. Objectives: Our main objective was to investigate retrospectively West Nile virus neuroinvasive disease (WNND) cases hospitalized during 2010–2017 and identified factors that can influence prognosis. Study design: We documented the demographic, epidemiologic, clinical and laboratory data of WNND and identified factors that can influence prognosis. The data were recruited through Infectious Diseases International Research Initiative (ID-IRI), which serves as a network for clinical researches. Results: We investigated 165 patients with WNND in 10 coun…