The Experts below are selected from a list of 141 Experts worldwide ranked by ideXlab platform
Andrei Surguchov - One of the best experts on this subject based on the ideXlab platform.
-
Synucleins in glaucoma: Implication of γ‐synuclein in glaucomatous alterations in the optic nerve
Journal of Neuroscience Research, 2002Co-Authors: Irina Surgucheva, B.k. Mcmahan, Stanislav I. Tomarev, Farid Ahmed, Andrei SurguchovAbstract:: Synucleins are small proteins associated with neurodegenerative diseases and some forms of cancer. They are studied predominantly in the brain; information about their presence and functions in ocular tissues is scarce. Here we describe the localization of three members of the synuclein family in the optic nerve of donors with different types of glaucoma compared with control samples from donors without ocular diseases. We did not find significant differences in the localization of alpha- and beta-synucleins in the optic nerve or retina of glaucoma patients compared with controls, whereas considerable redistribution of gamma-synuclein occurred in the glaucomatous optic nerve compared with control eye without glaucoma. In the optic nerve from control and glaucomatous individuals, nerve bundles are immunopositive for gamma-synuclein; however, a strong gamma-synuclein-immunopositive staining in a subset of glial cells was observed in the lamina and postlamina cribrosa regions of the optic nerve only in glaucoma patients. In the optic nerve of rats with episcleral vein cauterization used as an animal model of glaucoma, the quantity of both gamma-synuclein mRNA and protein was decreased compared with the optic nerves of control animals. Incubation of rat Astrocyte Culture at elevated hydrostatic pressure reduced the amount of gamma-synuclein but did not affect the quantities of actin and glial fibrillary acidic protein. These data suggest that significant changes in the pattern of expression and/or localization occur in the glaucomatous optic nerve for gamma-synuclein but not for alpha- and beta-members of the synuclein family.
Yael Hanein - One of the best experts on this subject based on the ideXlab platform.
-
calcium imaging mea recordings and immunostaining images dataset of neuron Astrocyte networks in Culture under the effect of norepinephrine
GigaScience, 2019Co-Authors: Sivan Kanner, Ari Barzilai, Yael HaneinAbstract:Background Monitoring the activity and morphology of neuron-Astrocyte networks in Culture is a powerful tool for studying dynamics, structure, and communication in neuron-Astrocyte networks independently or as a model of the sub-brain network. These Cultures are known to produce stereotypical patterns of activity, e.g., highly synchronized network bursts resembling sleep or seizure states, thus it enables the exploration of behaviors that can relate to brain function and disease. High-resolution microscopy of calcium imaging combined with simultaneous electrical recording provides a comprehensive overview on the network's dynamics. This setup makes it possible to apply global perturbations of electrical and chemical stimulation on the Cultures during the recording task and to record the effects on network activity on-line. Morphological changes in the Cultures can be obtained to have a complete dataset for structure-function study of neuron-Astrocyte networks in vitro. Findings The 4 TB of data presented here was recorded and imaged as part of an accompanying study looking at in vitro structure-function of neuron-Astrocyte networks. Simultaneous optical (calcium imaging) and electrical (micro-electrode array) recordings lasted 5-12 minutes and included spontaneous activity recording, electrical and chemical stimulation of neuron-Astrocyte, and isolated Astrocyte Cultures. The data include activity recordings of 58 different Cultures, with 1-2 regions of interest recorded for each Culture. Production procedures, experimental protocols, and reuse options are included. The data have been suitable to reveal changes in the activity and morphology of the Cultures and enabled observation and analysis of neuron-Astrocyte and isolated Astrocyte Culture behaviors under the applied perturbations. Conclusions Our dataset is sufficient to show significant changes in activity and morphology of neuron-Astrocyte networks in Culture under the applied stimulations. More than 100 recordings of 58 different Cultures give insight of the observation's significance and led to conclusions about Astrocyte activity and neuron-Astrocyte network communication. Making it available here will allow others to test new tools for calcium imaging analysis and extracellular neuronal voltage recordings.
Wilfried Seifert - One of the best experts on this subject based on the ideXlab platform.
-
glutamate induces the growth factors ngf bfgf the receptor fgf r1 and c fos mrna expression in rat Astrocyte Culture
Neuroscience Letters, 1993Co-Authors: Peter Pechan, Kamal Chowdhury, W Gerdes, Wilfried SeifertAbstract:Abstract The effect of glutamate on primary Cultures of rat cortical Astrocytes was studied using Northern blot hybridization. Incubation with glutamate (100 μM, 15 min) induced nerve growth factor (NGF), basic fibroblast growth factor (bFGF), FGF receptor (FGF-R1) and proto-oncogene c- fos gene expression in a time dependent manner. Maximal induction of NGF, bFGF and FGF-R1 mRNA was reached after 4 h of incubation (7.2-fold induction of NGF, 3-fold increase in bFGF and 3.6-fold induction of FGF-R1 mRNA). The induction kinetics of NGF, bFGF and FGF-R1 mRNA are similar. The rapid (1 h) 77-fold induction of the c- fos transcript preceeds the induction of the other genes tested.
-
free radicals induce gene expression of ngf and bfgf in rat Astrocyte Culture
Neuroreport, 1992Co-Authors: Peter Pechan, Kamal Chowdhury, Wilfried SeifertAbstract:Hydrogen peroxide (H2O2) is a type of active oxygen species produced mainly in blood by inflammation, ischemia or anoxia. Treatment of rat neonatal cortical Astrocytes in Culture with 0.2-1.0 mM H2O2 which is lethal for hippocampal neurons, increases nerve growth factor (NGF) and basic fibroblast growth factor (bFGF) mRNA content in a time dependent manner. H2O2 also increases c-fos mRNA expression, which is probably involved in the gene regulation of both NGF and bFGF. Maximal induction was reached after 6 h of incubation (5.7-fold increase in NGF and 2.4-fold induction of bFGF mRNA). Hydrogen peroxide induced bFGF and NGF gene expression suggests that neurotrophic factors in Astrocytes could be induced by lesion, consistent with their protective function in the CNS.
Raymond A Swanson - One of the best experts on this subject based on the ideXlab platform.
-
female sex hormones inhibit volume regulation in rat brain Astrocyte Culture
American Journal of Physiology-cell Physiology, 1994Co-Authors: C L Fraser, Raymond A SwansonAbstract:To determine whether sex steroids play any role in the increased morbidity associated with acute symptomatic hyponatremia in menstruant females, we studied the actions of estradiol, progesterone, a...
-
zinc toxicity and induction of the 72 kd heat shock protein in primary Astrocyte Culture
Glia, 1992Co-Authors: Raymond A Swanson, Frank R SharpAbstract:Zinc is a potent inducer of the 72 kD heat shock protein (HSP72). In brain, pathological conditions such as ischemia and seizures increase extracellular zinc. The present study examines the effect of zinc on HSP72 expression in rat primary cortical Astrocyte Culture. Astrocytes were grown to confluence and exposed to zinc chloride in CO2-equilibrated Earle's buffered salt solution. Expression of HSP72 was examined using immunocytochemistry. HSP72 was induced with zinc concentrations of 5 to 100 μM after 4 h exposures, or 200 to 300 μM after 15 min exposures. At the lower concentrations expression occurred in small clusters of contiguous cells. At concentrations high enough to cause cell death, HSP72-positive Astrocytes formed a continuous margin around patches of dead cells. These patterns of HSP72 expression are similar to the patterns seen after cerebral ischemia in vivo. Exposure to zinc at 100 μM for 4 h or 400 μM for 15 min caused greater than 90% cell death. Increases in extracellular zinc may contribute to HSP72 induction and Astrocyte death under ischemia and other pathological conditions in brain. © 1992 Wiley-Liss, Inc.
Patricia D Hurn - One of the best experts on this subject based on the ideXlab platform.
-
a novel method for assessing sex specific and genotype specific response to injury in Astrocyte Culture
Journal of Neuroscience Methods, 2008Co-Authors: Mingyue Liu, Esteban A Oyarzabal, Rui Yang, Stephanie J Murphy, Patricia D HurnAbstract:Female Astrocytes sustain less cell death from oxygen-glucose deprivation (OGD) than male Astrocytes. Arimidex, an aromatase inhibitor, abolishes these sex differences. To verify sex-dependent differences in P450 aromatase function in Astrocyte cell death following OGD, we developed a novel method that uses sex-specific and genotype-specific single pup primary Astrocyte Cultures from wild-type (WT) and aromatase-knockout (ArKO) mice. After determining sex by external and internal examination as well as PCR and genotype by PCR amplification of tail cDNA, we established Cultures from 1-3-day-old male and female WT and ArKO mice pups and grew them to confluence in estrogen-free media. Cell death was measured by lactate dehydrogenase (LDH) assay. Our study shows that, while WT female Astrocytes are more resistant to OGD than WT male cells, sex differences disappear in ArKO cells. Cell death is significantly increased in ArKO compared to WT in female Astrocytes but not male cells. Therefore, P450 aromatase appears to be essential in endogenous neuroprotection in females, and this finding may have clinical implications. This innovative technique may also be applied to other in vitro studies of sex-related functional differences.
