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Neural Stem Cells (neural + stem_cell)
Kinds of Neural Stem Cells Terms modified by Neural Stem Cells Selected AbstractsNeural Stem Cells and AlcoholALCOHOLISM, Issue 2 2003F. T. Crews This article summarizes the proceedings of a symposium held at the 2002 Research Society on Alcoholism Meeting in San Francisco, California. The aim of this symposium was to review research on the effects of ethanol on neural stems cells and neurogenesis. Ethanol is known to alter neurogenesis during development; however, recent studies indicate that the brain forms new neurons from stem cells throughout life. Furthermore, stem cells can be transplanted into the brain, creating exciting new possibilities to study brain function. The symposium covered these research areas. Dr. Michael W. Miller reviewed knowledge on the effects of ethanol on stem cell proliferation and differentiation during development. Dr. Wu Ma described studies in culture indicating that (1) neural stem cells express functional muscarinic acetylcholine receptors (mAchR), (2) mAchR-mediated proliferation involves Ca2+ signaling and mitogen-activated protein kinase phosphorylation, and (3) phosphoinositol-3 kinase is a downstream effector for mAchR-mediated cell proliferation via activation of Akt. Drs. Kim Nixon and Fulton T. Crews followed with in vivo studies on ethanol's effects on adult neural stem cell proliferation and differentiation. Dr. W. Michael Zawada described studies directed at dopamine neuron cell transplants into mammalian central nervous system. These studies clearly establish that ethanol has significant effects on stem cells. [source] A Novel Approach to Align Adult Neural Stem Cells on Micropatterned Conduits for Peripheral Nerve Regeneration: A Feasibility StudyARTIFICIAL ORGANS, Issue 1 2009Shan-hui Hsu Abstract There is a strong need for nerve-tissue engineering using the guide conduit and Schwann cells or neural stem cells (NSCs) with regeneration potential for injured peripheral nerves. In this study, micropatterned poly(d,l -lactide) (PLA) conduits were fabricated by microlithography and solvent-casting. The PLA conduits were seeded with the novel green fluorescent protein (GFP)-positive adult mouse NSCs obtained using the patented method of one of the authors. About 85% of the seeded NSCs were successfully aligned on the micropatterned conduits within 72 h and expressed the genes related to the production of neurotrophic factors. Gene expressions for the neurotrophic factors, such as nerve growth factor and brain-derived neurotrophic factor were upregulated by the micropatterned conduits at 72 h. The micropatterned PLA conduits seeded with the aligned NSCs were used to bridge the 10-mm sciatic nerve gaps in rats and were found to facilitate nerve repair and functional recovery during a period of 6 weeks compared with the nonseeded group. This model can be used to study the role of adult NSCs in peripheral-nerve regeneration in the future. [source] Effect of Neural Stem Cells on Apoptosis of PC12 Cells Induced by Serum DeprivationBIOTECHNOLOGY PROGRESS, Issue 4 2007Xiangqin Li Neural stem cells (NSCs) have a bright application prospect to be used to treat neurodegenerative diseases due to their capacity to give rise to the appropriate cell types when they are grafted. At present, however, the function of NSCs after transplantation is not quite ensured, whether to replace the degenerative cells or to secrete nutrient factors. On the other hand, pheochromocytoma cell line 12 (PC12) cells have been widely used for investigating Parkinsonapos;s disease (PD) since their apoptosis is similar to that of dopaminergic neuron cells. Therefore, the possible cytoprotective effects of NSCs on the apoptosis of PC12 cells induced by serum deprivation were investigated in this paper. PC12 cells were cocultured with NSCs in DMEM/F12 medium free of serum, and their morphologies, viabilities, and survival were observed with an inverted microscope and assessed with a CCK-8 assay. In addition, the concentrations of glial derived neurotrophic factor (GDNF) in different medium were detected with a GDNF Elisa kit, and the mechanism of NSCapos;s protective effect on PC12 cell apoptosis induced by serum deprivation was analyzed. The results showed that (1) PC12 cell apoptosis induced by serum deprivation increased with time, and only about 44.25% PC12 cells survived after 72 h; (2) NSCs culture medium protected against PC12 cell apoptosis insignificantly; (3) NSCs' supernatant and NSCs mildly prevented PC12 cells from apoptosis; (4) the amount of GDNF secreted by NSCs increased after the coculture with the apoptotic PC12 cells induced by serum deprivation. It can be concluded that there exists clear interaction between NSCs and apoptotic PC12 cells, and that GDNF secretion from NSCs is one of the important mechanisms to prevent the apoptosis of PC12 cells. [source] Passaging Protocols for Mammalian Neural Stem Cells in Suspension BioreactorsBIOTECHNOLOGY PROGRESS, Issue 2 2002Arindom Sen Mammalian neural stem cells (NSC) offer great promise as therapeutic agents for the treatment of central nervous system disorders. As a consequence of the large numbers of cells that will be needed for drug testing and transplantation studies, it is necessary to develop protocols for the large-scale expansion of mammalian NSC. Neural stem cells and early progenitor cells can be expanded in vitro as aggregates in controlled bioreactors using carefully designed media. The first objective of this study was to determine if it is possible to maintain a population of murine neural stem and progenitor cells as aggregates in suspension culture bioreactors over extended periods of time. We discovered that serial passaging of a mixture of aggregates sizes resulted in high viabilities, high viable cell densities, and good control of aggregate diameter. When the NSC aggregates were serially subcultured three times without mechanical dissociation, a total multiplication ratio of 2.9 × 103 was achieved over a period of 12 days, whereas the aggregate size was controlled (mean diameter less than 150 ,m) below levels at which necrosis would occur. Moreover, cell densities of 1.0 × 106 cells/mL were repeatedly achieved in batch culture with viabilities exceeding 80%. The second objective was to examine the proliferative potential of single cells shed from the surface of these aggregates. We found that the single cells, when subcultured, retained the capacity to generate new aggregates, gave rise to cultures with high viable cell densities and were able to differentiate into all of the primary cell phenotypes in the central nervous system. [source] Caspase inhibition increases survival of neural stem cells in the gastrointestinal tractNEUROGASTROENTEROLOGY & MOTILITY, Issue 4 2005M.-a . Micci Abstract, Neural stem cell (NSC) transplantation is a promising tool for the restoration of the enteric nervous system in a variety of motility disorders. Post-transplant survival represents a critical limiting factor for successful repopulation. The aim of this study was to determine the role of both immunological as well as non-immune-mediated mechanisms on post-transplant survival of NSC in the gut. Mouse CNS-derived NSC (CNS-NSC) were transplanted into the pylorus of recipient mice with and without the addition of a caspase-1 inhibitor (Ac-YVAD-cmk) in the injection media. In a separate experiment, CNS-NSC were transplanted in the pylorus of mice that were immunosuppressed by administration of cyclosporin A (CsA). Apoptosis and proliferation of the implanted cells was assessed 1 and 7 days post-transplantation. Survival was assessed 1 week post-transplantation. The degree of immunoresponse was also measured. The addition of a caspase-1 inhibitor significantly reduced apoptosis, increased proliferation and enhanced survival of CNS-NSC. CsA-treatment did not result in improved survival. Our results indicate that caspase-1 inhibition, but not immunosuppression, improves survival of CNS-NSC in the gut. Pre-treatment with a caspase-1 inhibitor may be a practical method to enhance the ability of transplanted CNS-NSC to survive in their new environment. [source] Nucleotides and epidermal growth factor induce parallel cytoskeletal rearrangements and migration in cultured adult murine neural stem cellsACTA PHYSIOLOGICA, Issue 2 2010I. Grimm Abstract Aim:, The adult subventricular zone (SVZ) contains neural stem cells that generate neuroblasts migrating to the olfactory bulb (OB) and differentiating into interneurones. The molecular cues controlling essential functions within the neurogenesis pathway such as proliferation, short and long distance migration, functional integration and cell survival are poorly understood. We have previously shown that cultured adult neural stem cells express a considerable variety of nucleotide receptors and that nucleotides and epidermal growth factor (EGF) induce converging intracellular signalling pathways that carry potential for synergism in the control of neural stem cell proliferation and cell survival. Here we investigate the role of EGF and the nucleotides ATP, ADP,S and UTP in neural stem cell migration. Methods:, Neural stem cells were prepared from adult mice and subjected to adherent culture. Labelling of F-actin was performed with tetramethylrhodamine isothiocyanate-phalloidin. Images were processed for quantitative evaluation of fluorescence labelling. Agonist-induced phosphorylation of AKT and focal adhesion kinase was analysed by quantitative Western blotting. Agonist-dependent cell migration was assayed using 48-well microchemotaxis chambers. Results:, Nucleotides and EGF induce the formation of stress fibres, an increase in the cortical actin cytoskeleton and in cell spreading. This is associated with increased phosphorylation of AKT and focal adhesion kinase. Using microchemotaxis chambers we demonstrate a parallel increase in cell migration. Conclusion:, Our results suggest that nucleotides and EGF acting as paracrine or autocrine signalling substances can be of relevance for structuring and maintaining the cytoarchitecture of the SVZ and the stream of neuroblasts migrating to the OB. [source] Neural stem cells for the treatment of disorders of the enteric nervous system: Strategies and challengesDEVELOPMENTAL DYNAMICS, Issue 1 2007Maria-Adelaide Micci Abstract The main goal of this review is to summarize the status of the research in the field of stem cells transplantation, as it is applicable to the treatment of gastrointestinal motility. This field of research has advanced tremendously in the past 10 years, and recent data produced in our laboratories as well as others is contributing to the excitement on the use of neural stem cells (NSC) as a valuable therapeutic approach for disorders of the enteric nervous system characterized by a loss of critical neuronal subpopulations. There are several sources of NSC, and here we describe therapeutic strategies for NSC transplantation in the gut. These include using NSC as a relatively nonspecific cellular replacement strategy in conditions where large populations of neurons or their subsets are missing or destroyed. As with many other recent "breakthroughs" stem cell therapy may eventually prove to be overrated. However, at the present time, it does appear to provide the hope for a true cure for many currently intractable diseases of both the central and the peripheral nervous system. Certainly more extensive research is needed in this field. We hope that our review will encourage new investigators in entering this field of research ad contribute to our knowledge of the potentials of NSC and other cells for the treatment of gastrointestinal dysmotility. Developmental Dynamics 236:33,43, 2007. © 2006 Wiley-Liss, Inc. [source] Absence of hematopoiesis from transplanted olfactory bulb neural stem cellsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2004Marķa J. Yusta-Boyo Abstract Neural stem cells giving rise to neurons and glia cells have been isolated from the embryonic and adult central nervous system. The extent to which they are able to differentiate into cells of non-neural lineages, such as the hematopoietic lineage, is nonetheless unclear. We previously reported the isolation of stem cells from the mouse olfactory bulb neuroepithelium. In the present study, we analysed whether olfactory bulb stem cells (OBSC) can generate cells with hematopoietic features. Cells were prepared from the olfactory bulbs of transgenic mice expressing enhanced green fluorescent protein (EGFP). In culture, transgenic cells proliferated with the same kinetics as wild-type cells. Following mitogen removal, both cell types gave rise to similar numbers of neurons, astrocytes and oligodendrocytes, indicating that EGFP overexpression does not alter OBSC proliferation and differentiation patterns. When these cells were injected into the tail vein of irradiated mice, no hematopoietic cells derived from the OBSC could be recovered in their peripheral blood, spleen or bone marrow. By contrast, when OBSC were transplanted into the adult brain, EGFP-positive cells were found in the striatum and corpus callosum; differentiated cells expressed antigenic markers of neurons and astrocytes. These results suggest that embryonic olfactory bulb stem cells are not endowed with the potential to produce hematopoiesis. [source] Ultrastructural and antigenic properties of neural stem cells and their progeny in adult rat subventricular zoneGLIA, Issue 2 2009Alexandre I. Danilov Abstract Neural stem cells (NSCs) in the subventricular zone (SVZ) continuously generate olfactory bulb interneurons in the adult rodent brain. Based on their ultrastructural and antigenic properties, NSCs, transient amplifying precursor cells, and neuroblasts (B, C, and A cells, respectively) have been distinguished in mouse SVZ. Here, we aimed to identify these cell types in rat SVZ ultrastructurally and at the light microscopy level, and to determine the antigenic properties of each cell type using gold and fluorescence immunolabeling. We found astrocytes with single cilia (NSCs, correspond to B cells) and neuroblasts (A cells). We also observed mitotic cells, ependymal cells, displaced ependymal cells, and mature astrocytes. In contrast, transient amplifying precursor cells (C cells) were not detected. The NSCs and neuroblasts had epidermal growth factor receptor (EGFR) and platelet-derived growth factor receptor alpha (PDGFR,) expressed on the ciliary apparatus and were the only cell types incorporating the proliferation marker BrdU. Throughout mitosis, EGFR and PDGFR, were associated with the microtubule of the mitotic spindle. Ependymal and displaced ependymal cells also expressed EGFR and PDGFR, on their cilia but did not incorporate BrdU. Our findings indicate that the NSCs in adult rat SVZ give rise directly to neuroblasts. During mitosis, the NSCs disassemble the primary cilium and symmetrically distribute EGFR and PDGFR, among their progeny. © 2008 Wiley-Liss, Inc. [source] Neural stem cells improve neuronal survival in cultured postmortem brain tissue from aged and Alzheimer patientsJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 5a 2008L. Wu Abstract Neurodegenerative diseases are progressive and incurable and are becoming ever more prevalent. To study whether neural stem cell can reactivate or rescue functions of impaired neurons in the human aging and neurodegenerating brain, we co-cultured postmortem slices from Alzheimer patients and control participants with rat embryonic day 14 (E14) neural stem cells. Viability staining based on the exclusion of ethidium bromide by intact plasma membranes showed that there were strikingly more viable cells and fewer dead cells in slices co-cultured with neural stem cells than in untreated slices. The presence of Alzheimer pathology in the brain slices did not influence this effect, although the slices from Alzheimer patients, in general, contained fewer viable cells. Co-culturing with rat E14 fibroblasts did not improve the viability of neurons in the human brain slices. Since the human slices and neural stem cells were separated by a membrane during co-culturing our data show for the first time that neural stem cells release diffusible factors that may improve the survival of aged and degenerating neurons in human brains. [source] Adult cerebrospinal fluid inhibits neurogenesis but facilitates gliogenesis from fetal rat neural stem cellsJOURNAL OF NEUROSCIENCE RESEARCH, Issue 14 2009Judith Buddensiek Abstract Neural stem cells (NSCs) are a promising source for cell replacement therapies for neurological diseases. Administration of NSCs into the cerebrospinal fluid (CSF) offers a nontraumatic transplantation method into the brain. However, cell survival and intraparenchymal migration of the transplants are limited. Furthermore, CSF was recently reported to be an important milieu for controlling stem cell processes in the brain. We studied the effects of adult human leptomeningeal CSF on the behavior of fetal rat NSCs. CSF increased survival of NSCs compared with standard culture media during stem cell maintenance and differentiation. The presence of CSF enhanced NSC differentiation, leading to a faster loss of self-renewal capacity and faster and stronger neurite outgrowth. Some of these effects (mainly cell survival, neurite brancing) were blocked by addition of the bone morphogenic protein (BMP) inhibitor noggin. After differentiation in CSF, significantly fewer MAP2ab+ neurons were found, but there were more GFAP+ astroglia compared with standard media. By RT-PCR analysis, we determined a decrease of mRNA of the NSC marker gene Nestin but an increase of Gfap mRNA during differentiation up to 72 hr in CSF compared with standard media. Our data demonstrate that adult human leptomeningeal CSF enhances cell survival of fetal rat NSCs during proliferation and differentiation. Furthermore, CSF provides a stimulus for gliogenesis but inhibits neurogenesis from fetal NSCs. Our data suggest that CSF contains factors such as BMPs regulating NSC behavior, and we hypothesize that fast differentiation of NSCs in CSF leads to a rapid loss of migration capacity of intrathecally transplanted NSCs. © 2009 Wiley-Liss, Inc. [source] Generation of spinal motor neurons from human fetal brain-derived neural stem cells: Role of basic fibroblast growth factorJOURNAL OF NEUROSCIENCE RESEARCH, Issue 2 2009Paivi M. Jordan Abstract Neural stem cells (NSCs) have some specified properties but are generally uncommitted and so can change their fate after exposure to environmental cues. It is unclear to what extent this NSC plasticity can be modulated by extrinsic cues and what are the molecular mechanisms underlying neuronal fate determination. Basic fibroblast growth factor (bFGF) is a well-known mitogen for proliferating NSCs. However, its role in guiding stem cells for neuronal subtype specification is undefined. Here we report that in-vitro-expanded human fetal forebrain-derived NSCs can generate cholinergic neurons with spinal motor neuron properties when treated with bFGF within a specific time window. bFGF induces NSCs to express the motor neuron marker Hb9, which is blocked by specific FGF receptor inhibitors and bFGF neutralizing antibodies. This development of spinal motor neuron properties is independent of selective proliferation or survival and does not require high levels of MAPK activation. Thus our study indicates that bFGF can play an important role in modulating plasticity and neuronal fate of human NSCs and presumably has implications for exploring the full potential of brain NSCs for clinical applications, particularly in spinal motor neuron regeneration. © 2008 Wiley-Liss, Inc. [source] Kainic acid triggers oligodendrocyte precursor cell proliferation and neuronal differentiation from striatal neural stem cellsJOURNAL OF NEUROSCIENCE RESEARCH, Issue 6 2007Carolina Redondo Abstract Glutamate is an excitatory amino acid that serves important functions in mammalian brain development through ,-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA)/ kainate receptor stimulation. Neural stem cells with self-renewal and multilineage potential are a useful tool to study the signals involved in the regulation of brain development. We have investigated the role played by AMPA/kainate receptors during the differentiation of neural stem cells derived from fetal rat striatum. The application of 1 and 10 ,M kainic acid increased significantly the phosphorylation of the cyclic AMP response element binding protein (CREB), raised bromodeoxyuridine incorporation in O4-positive oligodendrocyte precursors, and increased the number of O1-positive cells in the cultures. Increased CREB phosphorylation and proliferation were prevented by the AMPA receptor antagonist 4-4(4-aminophenyl)-1,2-dihydro-1-methyl-2-propylcarbamoyl-6,7-methylenedioxyphthalazine (SYM 2206) and by protein kinase A and protein kinase C inhibitors. Cultures treated with 100 ,M kainic acid showed decreased proliferation, a lower proportion of O1-positive cells, and apoptosis of O4-positive cells. None of these effects were prevented by SYM 2206, suggesting that kainate receptors take part in these events. We conclude that AMPA receptor stimulation by kainic acid promotes the proliferation of oligodendrocyte precursors derived from neural stem cells through a mechanism that requires the activation of CREB by protein kinase A and C. In the neurons derived from these cells, either AMPA or kainate receptor stimulation produces neuritic growth and larger cell bodies. © 2007 Wiley-Liss, Inc. [source] Stem cell biology of the central nervous systemJOURNAL OF NEUROSCIENCE RESEARCH, Issue 6 2002Hideyuki Okano Abstract Neural stem cells (NSCs) are multipotential progenitor cells that have self-renewal activities. A single NSC is capable of generating various kinds of cells within the central nervous system (CNS), including neurons, astrocytes, and oligodendrocytes. Because of these characteristics, there is increasing interest in NSCs and neural progenitor cells from the aspects of both basic developmental biology and therapeutic applications to the damaged brain. This special issue, dedicated to understanding the nature of the NSCs present in the CNS, presents an introduction to several avenues of research that may lead to feasible strategies for manipulating cells in situ to treat the damaged brain. The topics covered by these studies include the extracellular factors and signal transduction cascades involved in the differentiation and maintenance of NSCs, the population dynamics and locations of NSCs in embryonic and adult brains, prospective identification and isolation of NSCs, the induction of NSCs to adopt particular neuronal phenotypes, and their transplantation into the damaged CNS. © 2002 Wiley-Liss, Inc. [source] Amphiregulin is a mitogen for adult neural stem cellsJOURNAL OF NEUROSCIENCE RESEARCH, Issue 6 2002Anna Falk Abstract Neurons are continuously generated from stem cells in the hippocampus and along the lateral ventricles in the adult brain. Neural stem cells can be propagated in vitro in the presence of epidermal growth factor (EGF) or fibroblast growth factor-2. We report here that amphiregulin, a growth factor related to EGF, is a mitogen for adult mouse neural stem cells in vitro and displays potency similar to that of EGF. Neural stem cell cultures can be initiated and the cells propagated as efficiently in the presence of amphiregulin only as with EGF. Furthermore, we show that amphiregulin is expressed in the choroid plexus of the ventricular system and in the hippocampus in the adult brain, suggesting that amphiregulin may participate in the regulation of neural stem cell proliferation and neurogenesis in the adult brain. © 2002 Wiley-Liss, Inc. [source] Patterns of laminins and integrins in the embryonic ventricular zone of the CNSTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 6 2007Justin D. Lathia Abstract The extracellular matrix (ECM) provides both a physical framework and a microenvironment that supplies instructive signals from the earliest stages of multicellular development. As a first step toward understanding the role of the ECM in regulating the behavior of neural stem cells (NSCs), here we show the localization of laminins, a heterotrimeric family of ECM molecules expressed in many different stem cell microenvironments, and their corresponding receptors in the embryonic murine ventricular zone (VZ) within which the NSCs undergo symmetrical and asymmetrical divisions required for cortical development. In addition to the presence of laminins containing both the ,2 and ,4 chains, we find distinct patterns of ECM receptor expression in the VZ and in the overlying cortex. Neural stem cells derived from the VZ express high levels of the integrin laminin receptor ,6,1. At developmental stages at which NSCs undergo asymmetrical divisions, integrin ,1 was unevenly distributed in some mitotic pairs at the ventricular wall. These results suggest a significant role in the regulation of NSC fate for laminin/integrin signaling within the microenvironment of the VZ and provide a framework for future molecular and cellular analyses of the role of the ECM in neural development. J. Comp. Neurol. 505:630,643, 2007. © 2007 Wiley-Liss, Inc. [source] Neural stem cells: Mechanisms of fate specification and nuclear reprogramming in regenerative medicineBIOTECHNOLOGY JOURNAL, Issue 12 2008Carsten W. Lederer Abstract Recently, intense interest in the potential use of neural stem cells (NSC) in the clinical therapy of brain disease and injury has resulted in rapid progress in research on the properties of NSC, their innate and directed differentiation potential and the induced reprogramming of differentiated somatic cells to revert to a pluripotent NSC-like state. The aim of this review is to give an overview of our current operational definitions of the NSC lineage, the growing understanding of extrinsic and intrinsic mechanisms, including heritable but reversible epigenetic chromatin modifications that regulate the maintenance and differentiation of NSC in vivo, and to emphasize ground-breaking efforts of cellular reprogramming with the view to generating patient-specific stem cells for cell replacement therapy. This is set against a summary of current practical procedures for the isolation, research and application of NSC, and of the state of the art in NSC-based regenerative medicine of the nervous system. Both provide the backdrop for the translation of recent findings into innovative clinical applications, with the hope of increasing the safety, efficiency and ethical acceptability of NSC-based therapies in the near future. [source] Effect of Neural Stem Cells on Apoptosis of PC12 Cells Induced by Serum DeprivationBIOTECHNOLOGY PROGRESS, Issue 4 2007Xiangqin Li Neural stem cells (NSCs) have a bright application prospect to be used to treat neurodegenerative diseases due to their capacity to give rise to the appropriate cell types when they are grafted. At present, however, the function of NSCs after transplantation is not quite ensured, whether to replace the degenerative cells or to secrete nutrient factors. On the other hand, pheochromocytoma cell line 12 (PC12) cells have been widely used for investigating Parkinsonapos;s disease (PD) since their apoptosis is similar to that of dopaminergic neuron cells. Therefore, the possible cytoprotective effects of NSCs on the apoptosis of PC12 cells induced by serum deprivation were investigated in this paper. PC12 cells were cocultured with NSCs in DMEM/F12 medium free of serum, and their morphologies, viabilities, and survival were observed with an inverted microscope and assessed with a CCK-8 assay. In addition, the concentrations of glial derived neurotrophic factor (GDNF) in different medium were detected with a GDNF Elisa kit, and the mechanism of NSCapos;s protective effect on PC12 cell apoptosis induced by serum deprivation was analyzed. The results showed that (1) PC12 cell apoptosis induced by serum deprivation increased with time, and only about 44.25% PC12 cells survived after 72 h; (2) NSCs culture medium protected against PC12 cell apoptosis insignificantly; (3) NSCs' supernatant and NSCs mildly prevented PC12 cells from apoptosis; (4) the amount of GDNF secreted by NSCs increased after the coculture with the apoptotic PC12 cells induced by serum deprivation. It can be concluded that there exists clear interaction between NSCs and apoptotic PC12 cells, and that GDNF secretion from NSCs is one of the important mechanisms to prevent the apoptosis of PC12 cells. [source] Passaging Protocols for Mammalian Neural Stem Cells in Suspension BioreactorsBIOTECHNOLOGY PROGRESS, Issue 2 2002Arindom Sen Mammalian neural stem cells (NSC) offer great promise as therapeutic agents for the treatment of central nervous system disorders. As a consequence of the large numbers of cells that will be needed for drug testing and transplantation studies, it is necessary to develop protocols for the large-scale expansion of mammalian NSC. Neural stem cells and early progenitor cells can be expanded in vitro as aggregates in controlled bioreactors using carefully designed media. The first objective of this study was to determine if it is possible to maintain a population of murine neural stem and progenitor cells as aggregates in suspension culture bioreactors over extended periods of time. We discovered that serial passaging of a mixture of aggregates sizes resulted in high viabilities, high viable cell densities, and good control of aggregate diameter. When the NSC aggregates were serially subcultured three times without mechanical dissociation, a total multiplication ratio of 2.9 × 103 was achieved over a period of 12 days, whereas the aggregate size was controlled (mean diameter less than 150 ,m) below levels at which necrosis would occur. Moreover, cell densities of 1.0 × 106 cells/mL were repeatedly achieved in batch culture with viabilities exceeding 80%. The second objective was to examine the proliferative potential of single cells shed from the surface of these aggregates. We found that the single cells, when subcultured, retained the capacity to generate new aggregates, gave rise to cultures with high viable cell densities and were able to differentiate into all of the primary cell phenotypes in the central nervous system. [source] Guanosine improves motor behavior, reduces apoptosis, and stimulates neurogenesis in rats with parkinsonismJOURNAL OF NEUROSCIENCE RESEARCH, Issue 3 2009Caixin Su Abstract Parkinson's disease (PD) is characterized by progressive degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNc) caused by an abnormal rate of apoptosis. Endogenous stem cells in the adult mammalian brain indicate an innate potential for regeneration and possible resource for neuroregeneration in PD. We previously showed that guanosine prevents apoptosis even when administered 48 hr after the toxin 1-methyl-4-phenylpyridinium (MPP+). Here, we induced parkinsonism in rats with a proteasome inhibitor. Guanosine treatment reduced apoptosis, increased tyrosine hydroxylase,positive dopaminergic neurons and expression of tyrosine hydroxylase in the SNc, increased cellular proliferation in the SNc and subventricular zone, and ameliorated symptoms. Proliferating cells in the subventricular zone were nestin-positive adult neural progenitor/stem cells. Fibroblast growth factor-2-expressing cells were also increased by guanosine. Thus, guanosine protected cells from apoptosis and stimulated "intrinsic" adult progenitor/stem cells to become dopaminergic neurons in rats with proteasome inhibitor,induced PD. The cellular/molecular mechanisms underlying these effects may open new avenues for development of novel therapeutics for PD. © 2008 Wiley-Liss, Inc. [source] Expression of gangliosides in an immortalized neural progenitor/stem cell lineJOURNAL OF NEUROSCIENCE RESEARCH, Issue 5 2003Keiji Suetake Abstract Glycosphingolipids (GSLs) are known to play important roles in cellular growth and differentiation in the nervous system. The change in expression of gangliosides is correlated with crucial developmental events and is evolutionarily conserved among many vertebrate species. The emergence of neural progenitors represents a crucial step in neural development, but little is known about the exact composition and subcellular localization of gangliosides in neural progenitor cells. The C17.2 cell line was derived after v- myc transformation of neural progenitor cells isolated from neonatal mouse cerebellar cortex. The developmental potential of C17.2 cells is similar to that of endogenous neural progenitor/stem cells in that they are multipotential and capable of differentiating into all neural cell types. We characterized the GSL composition of C17.2 cells and found the presence of only a-series gangliosides. Subcellular localization studies revealed that GM1 and GD1a are localized mainly on the plasma membrane and partly in the cytoplasm, both as punctate clusters. Reverse transcription-polymerase chain reaction revealed the absence of ST-II transcripts in C17 cells, which most likely accounts for the lack of expression of b- and c-series complex gangliosides in this cell line. These data suggest that the divergence in ganglioside expression in C17.2 cells is regulated at the transcriptional level. © 2003 Wiley-Liss, Inc. [source] Neural stem cells improve neuronal survival in cultured postmortem brain tissue from aged and Alzheimer patientsJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 5a 2008L. Wu Abstract Neurodegenerative diseases are progressive and incurable and are becoming ever more prevalent. To study whether neural stem cell can reactivate or rescue functions of impaired neurons in the human aging and neurodegenerating brain, we co-cultured postmortem slices from Alzheimer patients and control participants with rat embryonic day 14 (E14) neural stem cells. Viability staining based on the exclusion of ethidium bromide by intact plasma membranes showed that there were strikingly more viable cells and fewer dead cells in slices co-cultured with neural stem cells than in untreated slices. The presence of Alzheimer pathology in the brain slices did not influence this effect, although the slices from Alzheimer patients, in general, contained fewer viable cells. Co-culturing with rat E14 fibroblasts did not improve the viability of neurons in the human brain slices. Since the human slices and neural stem cells were separated by a membrane during co-culturing our data show for the first time that neural stem cells release diffusible factors that may improve the survival of aged and degenerating neurons in human brains. [source] Longterm quiescent cells in the aged human subventricular neurogenic system specifically express GFAP-,AGING CELL, Issue 3 2010Simone A. Van Den Berge Summary A main neurogenic niche in the adult human brain is the subventricular zone (SVZ). Recent data suggest that the progenitors that are born in the human SVZ migrate via the rostral migratory stream (RMS) towards the olfactory bulb (OB), similar to what has been observed in other mammals. A subpopulation of astrocytes in the SVZ specifically expresses an assembly-compromised isoform of the intermediate filament protein glial fibrillary acidic protein (GFAP-,). To further define the phenotype of these GFAP-, expressing cells and to determine whether these cells are present throughout the human subventricular neurogenic system, we analysed SVZ, RMS and OB sections of 14 aged brain donors (ages 74-93). GFAP-, was expressed in the SVZ along the ventricle, in the RMS and in the OB. The GFAP-, cells in the SVZ co-expressed the neural stem cell (NSC) marker nestin and the cell proliferation markers proliferating cell nuclear antigen (PCNA) and Mcm2. Furthermore, BrdU retention was found in GFAP-, positive cells in the SVZ. In the RMS, GFAP-, was expressed in the glial net surrounding the neuroblasts. In the OB, GFAP-, positive cells co-expressed PCNA. We also showed that GFAP-, cells are present in neurosphere cultures that were derived from SVZ precursors, isolated postmortem from four brain donors (ages 63-91). Taken together, our findings show that GFAP-, is expressed in an astrocytic subpopulation in the SVZ, the RMS and the OB. Importantly, we provide the first evidence that GFAP-, is specifically expressed in longterm quiescent cells in the human SVZ, which are reminiscent of NSCs. [source] In vitro characterization of a human neural progenitor cell coexpressing SSEA4 and CD133JOURNAL OF NEUROSCIENCE RESEARCH, Issue 2 2007Perrine Barraud Abstract The stage-specific embryonic antigen 4 (SSEA4) is commonly used as a cell surface marker to identify the pluripotent human embryonic stem (ES) cells. Immunohistochemistry on human embryonic central nervous system revealed that SSEA4 is detectable in the early neuroepithelium, and its expression decreases as development proceeds. Flow cytometry analysis of forebrain-derived cells demonstrated that the SSEA4-expressing cells are enriched in the neural stem/progenitor cell fraction (CD133+), but are rarely codetected with the neural stem cell (NSC) marker CD15. Using a sphere-forming assay, we showed that both subfractions CD133+/SSEA4+ and CD133+/CD15+ isolated from the embryonic forebrain are enriched in neurosphere-initiating cells. In addition CD133, SSEA4, and CD15 expression is sustained in the expanded neurosphere cells and also mark subfractions of neurosphere-initiating cells. Therefore, we propose that SSEA4 associated with CD133 can be used for both the positive selection and the enrichment of neural stem/progenitor cells from human embryonic forebrain. © 2006 Wiley-Liss, Inc. [source] Pituitary adenylate cyclase-activating polypeptide regulates forebrain neural stem cells and neurogenesis in vitro and in vivoJOURNAL OF NEUROSCIENCE RESEARCH, Issue 6 2006Shigeki Ohta Abstract Recent studies suggest that adult neurogenesis can contribute significantly to recovery from brain damage. As a result, there is strong interest in the field in identifying potentially therapeutic factors capable of promoting increased expansion of endogenous neural stem cell (NSC) populations and increased neurogenesis. In the present study, we have investigated the effects of PACAP on the NSC populations of the embryonic and adult forebrain. Our results demonstrate that the PACAP receptor, PAC1-R, is expressed by both embryonic and adult NSCs. The activation of PACAP signaling in vitro enhanced NSC proliferation/survival through a protein kinase A (PKA)-independent mechanism. In contrast, PACAP promoted NSC self-renewal and neurogenesis through a mechanism dependent on PKA activation. Finally, we determined that the intracerebroventricular infusion of PACAP into the adult forebrain was sufficient to increase neurogenesis significantly in both the hippocampus and the subventricular zone. These results demonstrate PACAP is unique in that it is capable of promoting NSC proliferation/survival, self-renewal, and neurogenesis and, therefore, may be ideal for promoting the endogenous regeneration of damaged brain tissue. © 2006 Wiley-Liss, Inc. [source] Ethanol exposure during embryogenesis decreases the radial glial progenitorpool and affects the generation of neurons and astrocytesJOURNAL OF NEUROSCIENCE RESEARCH, Issue 3 2006Gemma Rubert Abstract Prenatal ethanol exposure induces functional abnormalities during brain development affecting neurogenesis and gliogenesis. We have previously reported that alcohol exposure during embryogenesis disrupts radial glia (RG) and gliogenesis. Taking into account the new role of RG as neural progenitors, we have investigated whether ethanol affects RG as a neural stem cell. We found that in utero ethanol exposure impairs cell proliferation and decreases neurons and astrocytes generated in cultured RG and in embryonic cerebral cortex. Telencephalic cultures obtained at E12 from ethanol-treated rats displayed a reduction in the proportion of actively dividing RG progenitors, as demonstrated by 5-bromo-2,-deoxyuridine incorporation, and in the percentage of brain lipid binding protein-positive RG. Consistently, neurosphere formation assay from E12 telencephalon showed a reduced number of multipotent progenitor cells in cultures isolated from ethanol-treated rats in comparison with pair-fed control group. Moreover, levels of activated Notch1 and fibroblast growth factor receptor 2, which regulate the maintenance of the progenitor state of RG, are decreased by prenatal ethanol exposure. These findings demonstrate that ethanol reduces the telencephalic RG progenitor pool and its transformation into neurons and astrocytes, which may contribute to an explanation of the defects in brain function often observed in fetal alcohol syndrome. © 2006 Wiley-Liss, Inc. [source] Human neural stem cell grafts in the spinal cord of SOD1 transgenic rats: Differentiation and structural integration into the segmental motor circuitryTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 4 2009Leyan Xu Abstract Cell replacement strategies for degenerative and traumatic diseases of the nervous system depend on the functional integration of grafted cells into host neural circuitry, a condition necessary for the propagation of physiological signals and, perhaps, targeting of trophic support to injured neurons. We have recently shown that human neural stem cell (NSC) grafts ameliorate motor neuron disease in SOD1 transgenic rodents. Here we study structural aspects of integration of neuronally differentiated human NSCs in the motor circuitry of SOD1 G93A rats. Human NSCs were grafted into the lumbar protuberance of 8-week-old SOD1 G93A rats; the results were compared to those on control Sprague-Dawley rats. Using pre-embedding immuno-electron microscopy, we found human synaptophysin (+) terminals contacting the perikarya and proximal dendrites of host , motor neurons. Synaptophysin (+) terminals had well-formed synaptic vesicles and were associated with membrane specializations primarily in the form of symmetrical synapses. To analyze the anatomy of motor circuits engaging differentiated NSCs, we injected the retrograde transneuronal tracer Bartha-pseudorabies virus (PRV) or the retrograde marker cholera toxin B (CTB) into the gastrocnemius muscle/sciatic nerve of SOD1 rats before disease onset and also into control rats. With this tracing, NSC-derived neurons were labeled with PRV but not CTB, a pattern suggesting that PRV entered NSC-derived neurons via transneuronal transfer from host motor neurons but not via direct transport from the host musculature. Our results indicate an advanced degree of structural integration, via functional synapses, of differentiated human NSCs into the segmental motor circuitry of SOD1-G93A rats. J. Comp. Neurol. 514:297,309, 2009. © 2009 Wiley-Liss, Inc. [source] Nucleotides and epidermal growth factor induce parallel cytoskeletal rearrangements and migration in cultured adult murine neural stem cellsACTA PHYSIOLOGICA, Issue 2 2010I. Grimm Abstract Aim:, The adult subventricular zone (SVZ) contains neural stem cells that generate neuroblasts migrating to the olfactory bulb (OB) and differentiating into interneurones. The molecular cues controlling essential functions within the neurogenesis pathway such as proliferation, short and long distance migration, functional integration and cell survival are poorly understood. We have previously shown that cultured adult neural stem cells express a considerable variety of nucleotide receptors and that nucleotides and epidermal growth factor (EGF) induce converging intracellular signalling pathways that carry potential for synergism in the control of neural stem cell proliferation and cell survival. Here we investigate the role of EGF and the nucleotides ATP, ADP,S and UTP in neural stem cell migration. Methods:, Neural stem cells were prepared from adult mice and subjected to adherent culture. Labelling of F-actin was performed with tetramethylrhodamine isothiocyanate-phalloidin. Images were processed for quantitative evaluation of fluorescence labelling. Agonist-induced phosphorylation of AKT and focal adhesion kinase was analysed by quantitative Western blotting. Agonist-dependent cell migration was assayed using 48-well microchemotaxis chambers. Results:, Nucleotides and EGF induce the formation of stress fibres, an increase in the cortical actin cytoskeleton and in cell spreading. This is associated with increased phosphorylation of AKT and focal adhesion kinase. Using microchemotaxis chambers we demonstrate a parallel increase in cell migration. Conclusion:, Our results suggest that nucleotides and EGF acting as paracrine or autocrine signalling substances can be of relevance for structuring and maintaining the cytoarchitecture of the SVZ and the stream of neuroblasts migrating to the OB. [source] Epigenetic regulation in neural stem cell differentiationDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 6 2010Berry Juliandi The central nervous system (CNS) is composed of three major cell types , neurons, astrocytes, and oligodendrocytes , which differentiate from common multipotent neural stem cells (NSCs). This differentiation process is regulated spatiotemporally during the course of mammalian development. It is becoming apparent that epigenetic regulation is an important cell-intrinsic program, which can interact with transcription factors and environmental cues to modulate the differentiation of NSCs. This knowledge is important given the potential of NSCs to produce specific CNS cell types that will be beneficial for clinical applications. Here we review recent findings that address molecular mechanisms of epigenetic and transcription factor-mediated regulation that specify NSC fate during CNS development, with a particular focus on the developing mammalian forebrain. [source] gfap and nestin reporter lines reveal characteristics of neural progenitors in the adult zebrafish brainDEVELOPMENTAL DYNAMICS, Issue 2 2009Chen Sok Lam Abstract Adult neurogenesis arises from niches that harbor neural stem cells (NSC). Although holding great promise for regenerative medicine, the identity of NSC remains elusive. In mammals, a key attribute of NSC is the expression of the filamentous proteins glial fibrillary acidic protein (GFAP) and NESTIN. To assess whether these two markers are relevant in the fish model, two transgenic zebrafish lines for gfap and nestin were generated. Analysis of adult brains showed that the fusion GFAP,green fluorescent protein closely mimics endogenous GFAP, while the nestin transgene recapitulates nestin at the ventricular zones. Cells expressing the two reporters display radial glial morphology, colocalize with the NSC marker Sox2, undergo proliferation, and are capable of self-renewal within the matrix of distinct thickness in the telencephalon. Together, these two transgenic lines reveal a conserved feature of putative NSC in the adult zebrafish brain and provide a means for the identification and manipulation of these cells in vivo. Developmental Dynamics 238:475,486, 2009. © 2009 Wiley-Liss, Inc. [source] | ||||||||||||||||||||||||||||