Search results for "nervous system"

An Assay to Determine Mechanisms of Rapid Autoantibody-Induced Neurotransmitter Receptor Endocytosis and Vesicular Trafficking in Autoimmune Encephal…

2019

N-Methyl-D-aspartate (NMDA) receptors (NMDARs) are among the most important excitatory neurotransmitter receptors in the human brain. Autoantibodies to the human NMDAR cause the most frequent form of autoimmune encephalitis involving autoantibody-mediated receptor cross-linking and subsequent internalization of the antibody-receptor complex. This has been deemed to represent the predominant antibody effector mechanism depleting the NMDAR from the synaptic and extra-synaptic neuronal cell membrane. To assess in detail the molecular mechanisms of autoantibody-induced NMDAR endocytosis, vesicular trafficking, and exocytosis we transiently co-expressed rat GluN1-1a-EGFP and GluN2B-ECFP alone or…

Inflammatory demyelination induces ependymal modifications concomitant to activation of adult (SVZ) stem cell proliferation

2017

Ependymal cells (E1/E2) and ciliated B1cells confer a unique pinwheel architecture to the ventricular surface of the subventricular zone (SVZ), and their cilia act as sensors to ventricular changes during development and aging. While several studies showed that forebrain demyelination reactivates the SVZ triggering proliferation, ectopic migration, and oligodendrogenesis for myelin repair, the potential role of ciliated cells in this process was not investigated. Using conventional and lateral wall whole mount preparation immunohistochemistry in addition to electron microscopy in a forebrain-targeted model of experimental autoimmune encephalomyelitis (tEAE), we show an early decrease in num…

Stable and Efficient Genetic Modification of Cells in the Adult Mouse V-SVZ for the Analysis of Neural Stem Cell Autonomous and Non-autonomous Effects

2016

Relatively quiescent somatic stem cells support life-long cell renewal in most adult tissues. Neural stem cells in the adult mammalian brain are restricted to two specific neurogenic niches: the subgranular zone of the dentate gyrus in the hippocampus and the ventricular-subventricular zone (V-SVZ; also called subependymal zone or SEZ) in the walls of the lateral ventricles. The development of in vivo gene transfer strategies for adult stem cell populations (i.e. those of the mammalian brain) resulting in long-term expression of desired transgenes in the stem cells and their derived progeny is a crucial tool in current biomedical and biotechnological research. Here, a direct in vivo method …

Characterization of multiciliated ependymal cells that emerge in the neurogenic niche of the aged zebrafish brain

2016

In mammals, ventricular walls of the developing brain maintain a neurogenic niche, in which radial glial cells act as neural stem cells (NSCs) and generate new neurons in the embryo. In the adult brain, the neurogenic niche is maintained in the ventricular-subventricular zone (V-SVZ) of the lateral wall of lateral ventricles and the hippocampal dentate gyrus. In the neonatal V-SVZ, radial glial cells transform into astrocytic postnatal NSCs and multiciliated ependymal cells. On the other hand, in zebrafish, radial glial cells continue to cover the surface of the adult telencephalic ventricle and maintain a higher neurogenic potential in the adult brain. However, the cell composition of the …

Recommendations for enterovirus diagnostics and characterisation within and beyond Europe

2018

Enteroviruses (EV) can cause severe neurological and respiratory infections, and occasionally lead to devastating outbreaks as previously demonstrated with EV-A71 and EV-D68 in Europe. However, these infections are still often underdiagnosed and EV typing data is not currently collected at European level. In order to improve EV diagnostics, collate data on severe EV infections and monitor the circulation of EV types, we have established European non-polio enterovirus network (ENPEN). First task of this cross-border network has been to ensure prompt and adequate diagnosis of these infections in Europe, and hence we present recommendations for non-polio EV detection and typing based on the co…

Prevention of an increase in cortical ligand binding to AMPA receptors may represent a novel mechanism of endogenous brain protection by G-CSF after …

2016

PURPOSE Using G-CSF deficient mice we recently demonstrated neuroprotective properties of endogenous G-CSF after ischemic stroke. The present follow-up study was designed to check, whether specific alterations in ligand binding densities of excitatory glutamate or inhibitory GABAA receptors may participate in this effect. METHODS Three groups of female mice were subjected to 45 minutes of MCAO: wildtype, G-CSF deficient and G-CSF deficient mice substituted with G-CSF. Infarct volumes were determined after 24 hours and quantitative in vitro receptor autoradiography was performed using [3H]MK-801, [3H]AMPA and [3H]muscimol for labeling of NMDA, AMPA and GABAA receptors, respectively. Ligand b…

Melanin-concentrating hormone axons, but not orexin or tyrosine hydroxylase axons, innervate the claustrum in the rat: An immunohistochemical study

2016

The claustrum is a small, elongated nucleus close to the external capsule and deep in the insular cortex. In rodents, this nucleus is characterized by a dense cluster of parvalbumin labeling. The claustrum is connected with the cerebral cortex. It does not project to the brainstem, but brainstem structures can influence this nucleus. To identify some specific projections from the lateral hypothalamus and midbrain, we analyzed the distribution of projections labeled with antibodies against tyrosine hydroxylase (TH), melanin-concentrating hormone (MCH), and hypocretin (Hcrt) in the region of the claustrum. The claustrum contains a significant projection by MCH axons, whereas it is devoid of T…

CNS Macrophages Control Neurovascular Development via CD95L.

2017

The development of neurons and vessels shares striking anatomical and molecular features, and it is presumably orchestrated by an overlapping repertoire of extracellular signals. CNS macrophages have been implicated in various developmental functions, including the morphogenesis of neurons and vessels. However, whether CNS macrophages can coordinately influence neurovascular development and the identity of the signals involved therein is unclear. Here, we demonstrate that activity of the cell surface receptor CD95 regulates neuronal and vascular morphogenesis in the post-natal brain and retina. Furthermore, we identify CNS macrophages as the main source of CD95L, and macrophage-specific del…

Taurine as an Essential Neuromodulator during Perinatal Cortical Development

2017

A variety of experimental studies demonstrated that neurotransmitters are an important factor for the development of the central nervous system, affecting neurodevelopmental events like neurogenesis, neuronal migration, programmed cell death, and differentiation. While the role of the classical neurotransmitters glutamate and gamma-aminobutyric acid (GABA) on neuronal development is well established, the aminosulfonic acid taurine has also been considered as possible neuromodulator during early neuronal development. The purpose of the present review article is to summarize the properties of taurine as neuromodulator in detail, focusing on the direct involvement of taurine on various neurode…

2019

The effects of ionotropic γ-aminobutyric acid receptor (GABA-A, GABAA) activation depends critically on the Cl−-gradient across neuronal membranes. Previous studies demonstrated that the intracellular Cl−-concentration ([Cl−]i) is not stable but shows a considerable amount of activity-dependent plasticity. To characterize how membrane properties and different molecules that are directly or indirectly involved in GABAergic synaptic transmission affect GABA-induced [Cl−]i changes, we performed compartmental modeling in the NEURON environment. These simulations demonstrate that GABA-induced [Cl−]i changes decrease at higher membrane resistance, revealing a sigmoidal dependency between both par…