Search results for " Oligodendrocyte"

Cytoprotective and antioxidant properties of organic selenides for the myelin-forming cells, oligodendrocytes.

2018

Abstract Here a new series of twenty-one organoselenides, of potential protective activity, were synthesized and tested for their intrinsic cytotoxicity, anti-apoptotic and antioxidant capacities in oligodendrocytes. Most of the organoselenides were able to decrease the ROS levels, revealing antioxidant properties. Compounds 5b and 7b showed a high glutathione peroxidase (GPx)-like activities, which were 1.5 folds more active than ebselen. Remarkably, compound 5a diminished the formation of the oligodendrocytes SubG1 peak in a concentration-dependent manner, indicating its anti-apoptotic properties. Furthermore, based on the SwissADME web interface, we performed an in-silico structure-activ…

Ultrastructural characterization of human oligodendrocytes and their progenitor cells by pre-embedding immunogold.

2021

Oligodendrocytes are the myelinating cells of the central nervous system. They provide trophic, metabolic, and structural support to neurons. In several pathologies such as multiple sclerosis (MS), these cells are severely affected and fail to remyelinate, thereby leading to neuronal death. The gold standard for studying remyelination is the g-ratio, which is measured by means of transmission electron microscopy (TEM). Therefore, studying the fine structure of the oligodendrocyte population in the human brain at different stages through TEM is a key feature in this field of study. Here we study the ultrastructure of oligodendrocytes, its progenitors, and myelin in 10 samples of human white …

Role of the epigenetic factor Sirt7 in neuroinflammation and neurogenesis.

2017

Epigenetic regulators are increasingly recognized as relevant modulators in the immune and nervous system. The class of sirtuins consists of NAD+-dependent histone deacetylases that regulate transcription. Sirtuin family member Sirt1 has already been shown to influence the disease course in an animal model of autoimmune neuroinflammation (experimental autoimmune encephalomyelitis (EAE). A role of Sirt7, a related epigenetic regulator, on immune system regulation has been proposed before, as these mice are more susceptible to develop inflammatory cardiomyopathy. Sirt7-/- animals showed no differences in clinical score compared to wild-type littermates after EAE induction with myelin oligoden…

2018

In this study we analysed the effects of prophylactic biolistic DNA vaccination with plasmids encoding the encephalitogenic protein myelin oligodendrocyte glycoprotein (MOG) on the severity of a subsequently MOGp35-55-induced EAE and on the underlying immune response. We compared the outcome of vaccination with MOG-encoding plasmids alone or in combination with vectors encoding the regulatory cytokines IL-10 and TGF-s1, respectively. MOG expression was restricted to skin dendritic cells (DCs) by the use of the DC-specific promoter of the fascin1 gene (pFscn-MOG). For comparison, the strong and ubiquitously active CMV promoter was employed (pCMV-MOG), which allows MOG expression in all trans…

Retinal myelinated nerve fibers associated with macular pseudohole

2008

We report the case of a 24-year-old woman who presented unilateral extensive peripapillary myelinated nerve fibers associated with macular pseudohole and bilateral low myopia. Visual acuity, slit lamp biomicroscopy, automated perimetry, fundus color photography, and optical coherence tomography (Stratus® OCT) were performed. We discuss the clinical findings and diagnostic details of unilateral extensive peripapillary myelinated nerve fibers associated with macular pseudohole.

B7‐H1 and CD8+Treg: The enigmatic role of B7‐H1 in peripheral tolerance

2009

The interaction between B7-H1 (PD-L1) expressed on APC with PD-1 expressed by T cells was shown previously to result in inhibition of T-cell activation and autoimmune diseases. A paper in this issue of the European Journal of Immunology demonstrates that DC B7-H1 expression can in fact enhance autoimmunity, rather than suppress it. Using a model of direct injection of self antigen-loaded DC into the CNS, the authors demonstrate that DC with intact B7-H1 expression exacerbate CNS autoimmune disease. Importantly, the improved disease outcome in animals treated with B7-H1(-/-) DC is a result of a population of CD8(+) Treg cells that expand at the site of autoimmune inflammation.

Cross-recognition of a myelin peptide by CD8+ T cells in the CNS is not sufficient to promote neuronal damage.

2015

Multiple sclerosis (MS) is an inflammatory disease of the CNS thought to be driven by CNS-specific T lymphocytes. Although CD8+T cells are frequently found in multiple sclerosis lesions, their distinct role remains controversial because direct signs of cytotoxicity have not been confirmedin vivo. In the present work, we determined that murine ovalbumin-transgenic (OT-1) CD8+T cells recognize the myelin peptide myelin oligodendrocyte glycoprotein 40–54 (MOG40–54) bothin vitroandin vivo. The aim of this study was to investigate whether such cross-recognizing CD8+T cells are capable of inducing CNS damagein vivo. Using intravital two-photon microscopy in the mouse model of multiple sclerosis, …

A novel plasmid DNA electroporation method allows transfection of murine DC.

2007

Under steady state conditions dendritic cells (DC) exert tolerogenic function, but acquire potent immunogenic function due to strong upregulation of costimulatory molecules and proinflammatory cytokines. In numerous studies the potential of modified DC to induce tolerance or immune reactions towards a distinct antigen has been demonstrated. However, DC are refractory to transfection with plasmid DNA by non-viral methods. In this study we have tested the suitability of a newly developed electroporation device to transfect immature murine bone-marrow derived DC (BM-DC). Transfected BM-DC expressed reporter molecules at considerable extent which renders this method suitable to perform all kind…

In Vivo Imaging of Partially Reversible Th17 Cell-Induced Neuronal Dysfunction in the Course of Encephalomyelitis

2010

SummaryNeuronal damage in autoimmune neuroinflammation is the correlate for long-term disability in multiple sclerosis (MS) patients. Here, we investigated the role of immune cells in neuronal damage processes in animal models of MS by monitoring experimental autoimmune encephalomyelitis (EAE) by using two-photon microscopy of living anaesthetized mice. In the brainstem, we detected sustained interaction between immune and neuronal cells, particularly during disease peak. Direct interaction of myelin oligodendrocyte glycoprotein (MOG)-specific Th17 and neuronal cells in demyelinating lesions was associated with extensive axonal damage. By combining confocal, electron, and intravital microsc…

Involvement of Kv3.1 potassium chanels in 7-ketocholesterol, 24S-hydroxycholesterol and C24 : 0-induced lipotoxicity on 158N and BV-2 cells : relatio…

2017

Potassium (K+) is involved in the regulation of cellular excitability, cell cycle regulation, cell viability, neuroprotection and maintenance of microglial and oligodendrocytic functions. Potassium dysfunction, described in several neurodegenerative diseases such as Alzheimer's Disease (AD), multiple sclerosis (MS), Parkinson's disease and Huntington's disease, may be a potential therapeutic target. The underlying toxic mechanisms of these neurodegenerative pathologies involve oxysterols, which are oxidized cholesterol derivatives, and fatty acids including those associated with peroxisomal metabolism. 7-ketocholesterol (7KC), 24S-hydroxycholesterol (24S-OHC) and tetracosanoic acid (C24:0),…