Search results for "Astrocyte"
showing 10 items of 209 documents
Neurogenesis in adult subventricular zone
2002
Much excitement has been generated by the identification of adult brain regions harboring neural stem cells and their continual generation of new neurons throughout life. This is an important departure from traditional views of the germinal potential of the postnatal brain. However, a more profound
Sodium dynamics: another key to astroglial excitability?
2012
Astroglial excitability is largely mediated by fluctuations in intracellular ion concentrations. In addition to generally acknowledged Ca 2+ excitability of astroglia, recent studies have demonstrated that neuronal activity triggers transient increases in the cytosolic Na + concentration ([Na + ] i ) in perisynaptic astrocytes. These [Na + ] i transients are controlled by multiple Na + -permeable channels and Na + -dependent transporters; spatiotemporally organized [Na + ] i dynamics in turn regulate diverse astroglial homeostatic responses such as metabolic/signaling utilization of lactate and glutamate, transmembrane transport of neurotransmitters and K + buffering. In particular, near-me…
Oligodendrocyte ablation triggers central pain independently of innate or adaptive immune responses in mice.
2014
Mechanisms underlying central neuropathic pain are poorly understood. Although glial dysfunction has been functionally linked with neuropathic pain, very little is known about modulation of pain by oligodendrocytes. Here we report that genetic ablation of oligodendrocytes rapidly triggers a pattern of sensory changes that closely resemble central neuropathic pain, which are manifest before overt demyelination. Primary oligodendrocyte loss is not associated with autoreactive T- and B-cell infiltration in the spinal cord and neither activation of microglia nor reactive astrogliosis contribute functionally to central pain evoked by ablation of oligodendrocytes. Instead, light and electron micr…
“Super p53” Mice Display Retinal Astroglial Changes
2013
Tumour-suppressor genes, such as the p53 gene, produce proteins that inhibit cell division under adverse conditions, as in the case of DNA damage, radiation, hypoxia, or oxidative stress (OS). The p53 gene can arrest proliferation and trigger death by apoptosis subsequent to several factors. In astrocytes, p53 promotes cell-cycle arrest and is involved in oxidative stress-mediated astrocyte cell death. Increasingly, astrocytic p53 is proving fundamental in orchestrating neurodegenerative disease pathogenesis. In terms of ocular disease, p53 may play a role in hypoxia due to ischaemia and may be involved in the retinal response to oxidative stress (OS). We studied the influence of the p53 ge…
Swelling, Acidosis, and Irreversible Damage of Glial Cells from Exposure to Arachidonic Acid in vitro
1994
Swelling and damage of C6 glioma cells and of primary cultured astrocytes were analyzed in vitro during incubation with arachidonic acid (AA; 20:4). The cells were suspended in a physiological medium supplemented with AA at concentrations of 0.001–1.0 m M. Cell swelling was quantified by flow cytometry with hydrodynamic focusing. Flow cytometry was also utilized for assessment of cell viability by exclusion of the fluorescent dye propidium iodide and for measurement of the intracellular pH (pHi) by 2′,7′-bis-(2-carboxyethyl)−5(and −6)carboxyfluorescein. Administration of AA caused an immediate dose-dependent swelling of C6 glioma cells, even at a concentration of 0.01 m M. At this level cel…
Refining in vitro neurotoxicity testing--the development of blood-brain barrier models.
2003
The purpose of this paper is to review the current state of development of advanced in vitro blood–brain barrier (BBB) models. The BBB is a special capillary bed that separates the blood from the central nervous system (CNS) parenchyma. Astrocytes maintain the integrity of the BBB, and, without astrocytic contacts, isolated brain capillary endothelial cells in culture lose their barrier characteristics. Therefore, when developing in vitro BBB models, it is important to add astrocytic factors into the culture system. Recently, novel filter techniques and co-culture methods have made it possible to develop models which resemble the in vivo functions of the BBB in an effective way. With a BBB…
Neuronal and BBB damage induced by sera from patients with secondary progressive multiple sclerosis.
2009
An important component of the pathogenic process of multiple sclerosis (MS) is the blood-brain barrier (BBB) damage. We recently set an in vitro model of BBB, based on a three-cell-type co-culture system, in which rat neurons and astrocytes synergistically induce brain capillary endothelial cells to form a monolayer with permeability properties resembling those of the physiological BBB. Herein we report that the serum from patients with secondary progressive multiple sclerosis (SPMS) has a damaging effect on isolated neurons. This finding suggests that neuronal damaging in MS could be a primary event and not only secondary to myelin damage, as generally assumed. SPMS serum affects the perme…
Activation of Neurogenesis in Multipotent Stem Cells Cultured In Vitro and in the Spinal Cord Tissue After Severe Injury by Inhibition of Glycogen Sy…
2020
AbstractThe inhibition of glycogen synthase kinase-3 (GSK-3) can induce neurogenesis, and the associated activation of Wnt/β-catenin signaling via GSK-3 inhibition may represent a means to promote motor function recovery following spinal cord injury (SCI) via increased astrocyte migration, reduced astrocyte apoptosis, and enhanced axonal growth. Herein, we assessed the effects of GSK-3 inhibition in vitro on the neurogenesis of ependymal stem/progenitor cells (epSPCs) resident in the mouse spinal cord and of human embryonic stem cell–derived neural progenitors (hESC-NPs) and human-induced pluripotent stem cell–derived neural progenitors (hiPSC-NPs) and in vivo on spinal cord tissue regenera…
Possible Role of Glymphatic System of the Brain in the Pathogenesis of High-Altitude Cerebral Edema
2018
Simka, Marian, Paweł Latacz, and Joanna Czaja. Possible role of glymphatic system of the brain in the pathogenesis of high-altitude cerebral edema. High Alt Med Biol. 19:394–397, 2018.—In this article, we suggest that the glymphatic system of the brain can play an important role in the pathogenesis of high-altitude cerebral edema (HACE). Water enters the intercellular space of the brain primarily through aquaporin-4 (AQP-4) water channels, the main component of the glymphatic system, whereas acetazolamide, pharmacological agent used in the prevention of HACE, is the blocker of the AQP-4 molecule. In animal experiments, cerebral edema caused by hypobaric hypoxia was associated with an increa…
3D cultures of rat astrocytes and brain capillary endothelial cells on Poly-L-lactic acid scaffolds
2016
Tissue engineering is an emerging multidisciplinary field that aims at reproducing in vitro and/or in vivo tissues with morphological and functional features similar to the biological tissue of the human body. In this communication we report setting of three-dimensional structures able to mimic the extracellular matrix of the nervous system: we prepared Poly-L-Lactic Acid (PLLA) porous scaffolds via thermally induced phase separation (TIPS), and investigated the parameters that influence porosity, average pore size and degree of interconnection, i.e. polymer concentration, temperature and time of process. Astrocytes and brain capillary endothelial cells (BCECs) were cultured on these three-…