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Sample records for mouse neural precursor

  1. Intraspinal transplantation of mouse and human neural precursor cells

    PubMed Central

    Weinger, Jason G.; Chen, Lu; Coleman, Ronald; Leang, Ronika; Plaisted, Warren C.; Loring, Jeanne F.; Lane, Thomas E.

    2013-01-01

    This unit describes the preparation and transplantation of human neural precursor cells (hNPCs) and mouse neural precursor cells (mNPCs) into the thoracic region of the mouse spinal cord. The techniques in this unit also describe how to prepare the mouse for surgery by performing a laminectomy to expose the spinal cord for transplantation. Here we show NPCs genetically labeled with eGFP transplanted into the spinal cord of a mouse following viralmediated demyelination can efficiently be detected via eGFP expression. Transplantation of these cells into the spinal cord is an efficacious way to determine their effects in neurological disorders such as multiple sclerosis, Alzheimer's disease, and spinal cord injury. PMID:24510791

  2. Clonal identification of multipotent precursors from adult mouse pancreas that generate neural and pancreatic lineages.

    PubMed

    Seaberg, Raewyn M; Smukler, Simon R; Kieffer, Timothy J; Enikolopov, Grigori; Asghar, Zeenat; Wheeler, Michael B; Korbutt, Gregory; van der Kooy, Derek

    2004-09-01

    The clonal isolation of putative adult pancreatic precursors has been an elusive goal of researchers seeking to develop cell replacement strategies for diabetes. We report the clonal identification of multipotent precursor cells from the adult mouse pancreas. The application of a serum-free, colony-forming assay to pancreatic cells enabled the identification of precursors from pancreatic islet and ductal populations. These cells proliferate in vitro to form clonal colonies that coexpress neural and pancreatic precursor markers. Upon differentiation, individual clonal colonies produce distinct populations of neurons and glial cells, pancreatic endocrine beta-, alpha- and delta-cells, and pancreatic exocrine and stellate cells. Moreover, the newly generated beta-like cells demonstrate glucose-dependent Ca(2+) responsiveness and insulin release. Pancreas colonies do not express markers of embryonic stem cells, nor genes suggestive of mesodermal or neural crest origins. These cells represent a previously unidentified adult intrinsic pancreatic precursor population and are a promising candidate for cell-based therapeutic strategies. PMID:15322557

  3. PPARβ/δ and PPARγ maintain undifferentiated phenotypes of mouse adult neural precursor cells from the subventricular zone

    PubMed Central

    Bernal, Carolina; Araya, Claudia; Palma, Verónica; Bronfman, Miguel

    2015-01-01

    The subventricular zone (SVZ) is one of the main niches of neural stem cells in the adult mammalian brain. Stem and precursor cells in this region are the source for neurogenesis and oligodendrogesis, mainly in the olfactory bulb and corpus callosum, respectively. The identification of the molecular components regulating the decision of these cells to differentiate or maintain an undifferentiated state is important in order to understand the modulation of neurogenic processes in physiological and pathological conditions. PPARs are a group of transcription factors, activated by lipid ligands, with important functions in cellular differentiation and proliferation in several tissues. In this work, we demonstrate that mouse adult neural precursor cells (NPCs), in situ and in vitro, express PPARβ/δ and PPARγ. Pharmacological activation of both PPARs isoforms induces proliferation and maintenance of the undifferentiated phenotype. Congruently, inhibition of PPARβ/δ and PPARγ results in a decrease of proliferation and loss of the undifferentiated phenotype. Interestingly, PPARγ regulates the level of EGFR in adult NPCs, concurrent with it is function described in embryonic NPCs. Furthermore, we describe for the first time that PPARβ/δ regulates SOX2 level in adult NPCs, probably through a direct transcriptional regulation, as we identified two putative PPAR response elements in the promoter region of Sox2. EGFR and SOX2 are key players in neural stem/precursor cells self-renewal. Finally, rosiglitazone, a PPARγ ligand, increases PPARβ/δ level, suggesting a possible cooperation between these two PPARs in the control of cell fate behavior. Our work contributes to the understanding of the molecular mechanisms associated to neural cell fate decision and places PPARβ/δ and PPARγ as interesting new targets of modulation of mammalian brain homeostasis. PMID:25852474

  4. PPARβ/δ and PPARγ maintain undifferentiated phenotypes of mouse adult neural precursor cells from the subventricular zone.

    PubMed

    Bernal, Carolina; Araya, Claudia; Palma, Verónica; Bronfman, Miguel

    2015-01-01

    The subventricular zone (SVZ) is one of the main niches of neural stem cells in the adult mammalian brain. Stem and precursor cells in this region are the source for neurogenesis and oligodendrogesis, mainly in the olfactory bulb and corpus callosum, respectively. The identification of the molecular components regulating the decision of these cells to differentiate or maintain an undifferentiated state is important in order to understand the modulation of neurogenic processes in physiological and pathological conditions. PPARs are a group of transcription factors, activated by lipid ligands, with important functions in cellular differentiation and proliferation in several tissues. In this work, we demonstrate that mouse adult neural precursor cells (NPCs), in situ and in vitro, express PPARβ/δ and PPARγ. Pharmacological activation of both PPARs isoforms induces proliferation and maintenance of the undifferentiated phenotype. Congruently, inhibition of PPARβ/δ and PPARγ results in a decrease of proliferation and loss of the undifferentiated phenotype. Interestingly, PPARγ regulates the level of EGFR in adult NPCs, concurrent with it is function described in embryonic NPCs. Furthermore, we describe for the first time that PPARβ/δ regulates SOX2 level in adult NPCs, probably through a direct transcriptional regulation, as we identified two putative PPAR response elements in the promoter region of Sox2. EGFR and SOX2 are key players in neural stem/precursor cells self-renewal. Finally, rosiglitazone, a PPARγ ligand, increases PPARβ/δ level, suggesting a possible cooperation between these two PPARs in the control of cell fate behavior. Our work contributes to the understanding of the molecular mechanisms associated to neural cell fate decision and places PPARβ/δ and PPARγ as interesting new targets of modulation of mammalian brain homeostasis. PMID:25852474

  5. Mechanisms of mouse neural precursor expansion after neonatal hypoxia-ischemia.

    PubMed

    Buono, Krista D; Goodus, Matthew T; Guardia Clausi, Mariano; Jiang, Yuhui; Loporchio, Dean; Levison, Steven W

    2015-06-10

    Neonatal hypoxia-ischemia (H-I) is the leading cause of brain damage resulting from birth complications. Studies in neonatal rats have shown that H-I acutely expands the numbers of neural precursors (NPs) within the subventricular zone (SVZ). The aim of these studies was to establish which NPs expand after H-I and to determine how leukemia inhibitory factor (LIF) insufficiency affects their response. During recovery from H-I, the number of Ki67(+) cells in the medial SVZ of the injured hemisphere increased. Similarly, the number and size of primary neurospheres produced from the injured SVZ increased approximately twofold versus controls, and, upon differentiation, more than twice as many neurospheres from the damaged brain were tripotential, suggesting an increase in neural stem cells (NSCs). However, multimarker flow cytometry for CD133/LeX/NG2/CD140a combined with EdU incorporation revealed that NSC frequency diminished after H-I, whereas that of two multipotential progenitors and three unique glial-restricted precursors expanded, attributable to changes in their proliferation. By quantitative PCR, interleukin-6, LIF, and CNTF mRNA increased but with significantly different time courses, with LIF expression correlating best with NP expansion. Therefore, we evaluated the NP response to H-I in LIF-haplodeficient mice. Flow cytometry revealed that one subset of multipotential and bipotential intermediate progenitors did not increase after H-I, whereas another subset was amplified. Altogether, our studies demonstrate that neonatal H-I alters the composition of the SVZ and that LIF is a key regulator for a subset of intermediate progenitors that expand during acute recovery from neonatal H-I. PMID:26063918

  6. Mechanisms of Mouse Neural Precursor Expansion after Neonatal Hypoxia-Ischemia

    PubMed Central

    Buono, Krista D.; Goodus, Matthew T.; Guardia Clausi, Mariano; Jiang, Yuhui; Loporchio, Dean

    2015-01-01

    Neonatal hypoxia-ischemia (H-I) is the leading cause of brain damage resulting from birth complications. Studies in neonatal rats have shown that H-I acutely expands the numbers of neural precursors (NPs) within the subventricular zone (SVZ). The aim of these studies was to establish which NPs expand after H-I and to determine how leukemia inhibitory factor (LIF) insufficiency affects their response. During recovery from H-I, the number of Ki67+ cells in the medial SVZ of the injured hemisphere increased. Similarly, the number and size of primary neurospheres produced from the injured SVZ increased approximately twofold versus controls, and, upon differentiation, more than twice as many neurospheres from the damaged brain were tripotential, suggesting an increase in neural stem cells (NSCs). However, multimarker flow cytometry for CD133/LeX/NG2/CD140a combined with EdU incorporation revealed that NSC frequency diminished after H-I, whereas that of two multipotential progenitors and three unique glial-restricted precursors expanded, attributable to changes in their proliferation. By quantitative PCR, interleukin-6, LIF, and CNTF mRNA increased but with significantly different time courses, with LIF expression correlating best with NP expansion. Therefore, we evaluated the NP response to H-I in LIF-haplodeficient mice. Flow cytometry revealed that one subset of multipotential and bipotential intermediate progenitors did not increase after H-I, whereas another subset was amplified. Altogether, our studies demonstrate that neonatal H-I alters the composition of the SVZ and that LIF is a key regulator for a subset of intermediate progenitors that expand during acute recovery from neonatal H-I. PMID:26063918

  7. Characterization of Np95 expression in mouse brain from embryo to adult: A novel marker for proliferating neural stem/precursor cells

    PubMed Central

    Murao, Naoya; Matsuda, Taito; Noguchi, Hirofumi; Koseki, Haruhiko; Namihira, Masakazu; Nakashima, Kinichi

    2014-01-01

    Nuclear protein 95 KDa (Np95, also known as UHRF1 or ICBP90) plays an important role in maintaining DNA methylation of newly synthesized DNA strands by recruiting DNA methyltransferase 1 (DNMT1) during cell division. In addition, Np95 participates in chromatin remodeling by interacting with histone modification enzymes such as histone deacetylases. However, its expression pattern and function in the brain have not been analyzed extensively. We here investigated the expression pattern of Np95 in the mouse brain, from developmental to adult stages. In the fetal brain, Np95 is abundantly expressed at the midgestational stage, when a large number of neural stem/precursor cells (NS/PCs) exist. Interestingly, Np95 is expressed specifically in NS/PCs but not in differentiated cells such as neurons or glial cells. Furthermore, we demonstrate that Np95 is preferentially expressed in type 2a cells, which are highly proliferative NS/PCs in the dentate gyrus of the adult hippocampus. Moreover, the number of Np95-expressing cells increases in response to kainic acid administration or to voluntary running, which are known to enhance the proliferation of adult NS/PCs. These results suggest that Np95 participates in the process of proliferation and differentiation of NS/PCs, and that it should be a useful novel marker for proliferating NS/PCs, facilitating the analysis of the complex behavior of NS/PCs in the brain.

  8. Neural Precursor Lineages Specify Distinct Neocortical Pyramidal Neuron Types

    PubMed Central

    Tyler, William A.; Medalla, Maria; Guillamon-Vivancos, Teresa

    2015-01-01

    Several neural precursor populations contemporaneously generate neurons in the developing neocortex. Specifically, radial glial stem cells of the dorsal telencephalon divide asymmetrically to produce excitatory neurons, but also indirectly to produce neurons via three types of intermediate progenitor cells. Why so many precursor types are needed to produce neurons has not been established; whether different intermediate progenitor cells merely expand the output of radial glia or instead generate distinct types of neurons is unknown. Here we use a novel genetic fate mapping technique to simultaneously track multiple precursor streams in the developing mouse brain and show that layer 2 and 3 pyramidal neurons exhibit distinctive electrophysiological and structural properties depending upon their precursor cell type of origin. These data indicate that individual precursor subclasses synchronously produce functionally different neurons, even within the same lamina, and identify a primary mechanism leading to cortical neuronal diversity. PMID:25878286

  9. Amyloid precursor protein and neural development.

    PubMed

    Nicolas, Maya; Hassan, Bassem A

    2014-07-01

    Interest in the amyloid precursor protein (APP) has increased in recent years due to its involvement in Alzheimer's disease. Since its molecular cloning, significant genetic and biochemical work has focused on the role of APP in the pathogenesis of this disease. Thus far, however, these studies have failed to deliver successful therapies. This suggests that understanding the basic biology of APP and its physiological role during development might be a crucial missing link for a better comprehension of Alzheimer's disease. Here, we present an overview of some of the key studies performed in various model organisms that have revealed roles for APP at different stages of neuronal development. PMID:24961795

  10. Mouse models for neural tube closure defects.

    PubMed

    Juriloff, D M; Harris, M J

    2000-04-12

    Neural tube closure defects (NTDs), in particular anencephaly and spina bifida, are common human birth defects (1 in 1000), their genetics is complex and their risk is reduced by periconceptional maternal folic acid supplementation. There are > 60 mouse mutants and strains with NTDs, many reported within the past 2 years. Not only are NTD mutations at loci widely heterogeneous in function, but also most of the mutants demonstrate variable low penetrance and some show complex inheritance patterns (e.g. SELH/Bc, Abl / Arg, Mena / Profilin1 ). In most of these mouse models, the NTDs are exencephaly (equivalent to anencephaly) or spina bifida or both, reflecting failure of neural fold elevation in well defined, mechanistically distinct elevation zones. NTD risk is reduced in various models by different maternal nutrient supplements, including folic acid ( Pax3, Cart1, Cd mutants), inositol ( ct ) and methionine ( Axd ). Lack of de novo methylation in embryos ( Dnmt3b -null) leads to NTD risk, and we suggest a potential link between methylation and the observed female excess among cranial NTDs in several models. Some surprising NTD mutants ( Gadd45a, Terc, Trp53 ) suggest that genes with a basic mitotic function also have a function specific to neural fold elevation. The genes mutated in several mouse NTD models involve actin regulation ( Abl/Arg, Macs, Mena/Profilin1, Mlp, Shrm, Vcl ), support the postulated key role of actin in neural fold elevation, and may be a good candidate pathway to search for human NTD genes. PMID:10767323

  11. In vitro clonal analysis of mouse neural crest development.

    PubMed

    Ito, K; Morita, T; Sieber-Blum, M

    1993-06-01

    Analysis of lineage segregation during mammalian neural crest development has not been sufficiently performed due to technical difficulties. In the present study, therefore, we established a clonal culture system of mouse neural crest cells in order to analyze developmental potentials of individual neural crest cells and their patterns of lineage segregation. 12-O-Tetradecanoylphorbol-13-acetate (TPA) and cholera toxin (CT) were applied to culture medium to trigger melanogenic differentiation of mouse neural crest cells. Three morphologically distinct types of clones were observed. (1) "Pigmented clones" consisted of melanocytes only, suggesting that the clone-forming cells were committed to the melanogenic lineage. These clones were observed only in the presence of TPA and CT. The proportion of this type of clone (8%) was much lower than that of the equivalent type of clone in quail trunk neural crest (40-60%; Sieber-Blum and Cohen, 1980, Dev. Biol. 80, 96-106). It therefore appears that the segregation pattern to the melanogenic lineage during mouse neural crest development in vitro differs quantitatively from that in the quail. (2) "Mixed clones" consisted of pigmented and unpigmented cells. Like pigmented clones, they were observed only in the presence of TPA and CT. The clones contained up to four types of cells: melanocytes, S100-positive cells (Schwann cells or melanogenic precursor cells), serotonin (5-HT)-positive autonomic neuron-like cells, and substance P (SP)-immunoreactive sensory neuron-like cells. Thus, at least some mixed clone-forming cells are pluripotent. (3) Two classes of "unpigmented clones" were observed that consisted of unpigmented cells only. These clones developed in the presence and absence of TPA and CT. Unpigmented clones in one class contained up to three types of cells as well as other, as yet unidentified cells: S100-, 5-HT-, and SP-positive cells. This observation suggests that at least some of these clones originate from cells

  12. The Snail Transcription Factor Regulates the Numbers of Neural Precursor Cells and Newborn Neurons throughout Mammalian Life

    PubMed Central

    Zander, Mark A.; Cancino, Gonzalo I.; Gridley, Thomas; Kaplan, David R.; Miller, Freda D.

    2014-01-01

    The Snail transcription factor regulates diverse aspects of stem cell biology in organisms ranging from Drosophila to mammals. Here we have asked whether it regulates the biology of neural precursor cells (NPCs) in the forebrain of postnatal and adult mice, taking advantage of a mouse containing a floxed Snail allele (Snailfl/fl mice). We show that when Snail is inducibly ablated in the embryonic cortex, this has long-term consequences for cortical organization. In particular, when Snailfl/fl mice are crossed to Nestin-cre mice that express Cre recombinase in embryonic neural precursors, this causes inducible ablation of Snail expression throughout the postnatal cortex. This loss of Snail causes a decrease in proliferation of neonatal cortical neural precursors and mislocalization and misspecification of cortical neurons. Moreover, these precursor phenotypes persist into adulthood. Adult neural precursor cell proliferation is decreased in the forebrain subventricular zone and in the hippocampal dentate gyrus, and this is coincident with a decrease in the number of adult-born olfactory and hippocampal neurons. Thus, Snail is a key regulator of the numbers of neural precursors and newborn neurons throughout life. PMID:25136812

  13. microRNA regulation of neural precursor self-renewal and differentiation

    PubMed Central

    Hudish, Laura I; Appel, Bruce

    2014-01-01

    During early stages of development of the vertebrate central nervous system, neural precursors divide symmetrically to produce new precursors, thereby expanding the precursor population. During middle stages of neural development, precursors switch to an asymmetric division pattern whereby each mitosis produces one new precursor and one cell that differentiates as a neuron or glial cell. At late stages of development, most precursors stop dividing and terminally differentiate. Par complex proteins are associated with the apical membrane of neural precursors and promote precursor self-renewal. How Par proteins are down regulated to bring precursor self-renewal to an end has not been known. Our investigations of zebrafish neural development revealed that the microRNA miR-219 negatively regulates apical Par proteins, thereby promoting cessation of neural precursor division and driving terminal differentiation.

  14. Ataxin-1 regulates proliferation of hippocampal neural precursors.

    PubMed

    Asher, M; Johnson, A; Zecevic, B; Pease, D; Cvetanovic, M

    2016-05-13

    Polyglutamine expansion in the protein ATAXIN-1 (ATXN1) causes spinocerebellar ataxia type 1 (SCA1), an inherited neurodegenerative disease characterized by motor deficits, cognitive impairment and depression. Although ubiquitously expressed, mutant ATXN1 causes neurodegeneration primarily in the cerebellum, which is responsible for the observed motor deficits. The role of ATXN1 outside of the cerebellum and the causes of cognitive deficits and depression in SCA1 are less understood. In this study, we demonstrate a novel role of ATXN1 in the hippocampus as a regulator of adult neurogenesis. Adult hippocampal neurogenesis is the process of generating new hippocampal neurons and is linked to cognition and mood. We found that loss of ATXN1 causes a decrease in hippocampal neurogenesis in ATXN1 null (Atxn1(-/-)) mice. This decrease was caused by reduced proliferation of neural precursors in the hippocampus of Atxn1(-/-) mice, and persisted even when Atxn1(-/-) hippocampal neural precursors were removed from their natural environment and grown in vitro, suggesting that ATXN1 affects proliferation in a cell-autonomous manner. Moreover, expression of ATXN1 with a pathological polyglutamine (polyQ) expansion in wild-type neural precursor cells inhibited their proliferation. Our data establish a novel role for ATXN1 in the hippocampus as an intrinsic regulator of precursor cell proliferation, and suggest a mechanism by which polyQ expansion and loss of ATXN1 affect hippocampal function, potentially contributing to cognitive deficits and depression. These results indicate that while depletion of ATXN1 is a promising therapeutic approach to treat the cerebellar aspects of SCA1, this approach should be employed with caution given the potential for side effects on hippocampal function with loss of wild-type ATXN1. PMID:26876606

  15. Prolactin Stimulates Precursor Cells in the Adult Mouse Hippocampus

    PubMed Central

    Walker, Tara L.; Vukovic, Jana; Koudijs, Margaretha M.; Blackmore, Daniel G.; Mackay, Eirinn W.; Sykes, Alex M.; Overall, Rupert W.; Hamlin, Adam S.; Bartlett, Perry F.

    2012-01-01

    In the search for ways to combat degenerative neurological disorders, neurogenesis-stimulating factors are proving to be a promising area of research. In this study, we show that the hormonal factor prolactin (PRL) can activate a pool of latent precursor cells in the adult mouse hippocampus. Using an in vitro neurosphere assay, we found that the addition of exogenous PRL to primary adult hippocampal cells resulted in an approximate 50% increase in neurosphere number. In addition, direct infusion of PRL into the adult dentate gyrus also resulted in a significant increase in neurosphere number. Together these data indicate that exogenous PRL can increase hippocampal precursor numbers both in vitro and in vivo. Conversely, PRL null mice showed a significant reduction (approximately 80%) in the number of hippocampal-derived neurospheres. Interestingly, no deficit in precursor proliferation was observed in vivo, indicating that in this situation other niche factors can compensate for a loss in PRL. The PRL loss resulted in learning and memory deficits in the PRL null mice, as indicated by significant deficits in the standard behavioral tests requiring input from the hippocampus. This behavioral deficit was rescued by direct infusion of recombinant PRL into the hippocampus, indicating that a lack of PRL in the adult mouse hippocampus can be correlated with impaired learning and memory. PMID:22973440

  16. Regulation of proliferation and histone acetylation in embryonic neural precursors by CREB/CREM signaling

    PubMed Central

    Parlato, Rosanna; Mandl, Claudia; Hölzl-Wenig, Gabriele; Liss, Birgit; Tucker, Kerry L; Ciccolini, Francesca

    2014-01-01

    The transcription factor CREB (cAMP-response element binding protein) regulates differentiation, migration, survival and activity-dependent gene expression in the developing and mature nervous system. However, its specific role in the proliferation of embryonic neural progenitors is still not completely understood. Here we investigated how CREB regulates proliferation of mouse embryonic neural progenitors by a conditional mutant lacking Creb gene in neural progenitors. In parallel, we explored possible compensatory effects by the genetic ablation of another member of the same gene family, the cAMP-responsive element modulator (Crem). We show that CREB loss differentially impaired the proliferation, clonogenic potential and self-renewal of precursors derived from the ganglionic eminence (GE), in comparison to those derived from the cortex. This phenotype was associated with a specific reduction of histone acetylation in the GE of CREB mutant mice, and this reduction was rescued in vivo by inhibition of histone deacetylation. These observations indicate that the impaired proliferation could be caused by a reduced acetyltransferase activity in Creb conditional knock-out mice. These findings support a crucial role of CREB in controlling embryonic neurogenesis and propose a novel mechanism by which CREB regulates embryonic neural development.

  17. Serotonin regulates mouse cranial neural crest migration.

    PubMed Central

    Moiseiwitsch, J R; Lauder, J M

    1995-01-01

    Serotonergic agents (uptake inhibitors, receptor ligands) cause significant craniofacial malformations in cultured mouse embryos suggesting that 5-hydroxytryptamine (serotonin) (5-HT) may be an important regulator of craniofacial development. To determine whether serotonergic regulation of cell migration might underly some of these effects, cranial neural crest (NC) explants from embryonic day 9 (E9) (plug day = E1) mouse embryos or dissociated mandibular mesenchyme cells (derived from NC) from E12 embryos were placed in a modified Boyden chamber to measure effects of serotonergic agents on cell migration. A dose-dependent effect of 5-HT on the migration of highly motile cranial NC cells was demonstrated, such that low concentrations of 5-HT stimulated migration, whereas this effect was progressively lost as the dose of 5-HT was increased. In contrast, most concentrations of 5-HT inhibited migration of less motile, mandibular mesenchyme cells. To investigate the possible involvement of specific 5-HT receptors in the stimulation of NC migration, several 5-HT subtype-selective antagonists were used to block the effects of the most stimulatory dose of 5-HT (0.01 microM). Only NAN-190 (a 5-HT1A antagonist) inhibited the effect of 5-HT, suggesting involvement of this receptor. Further evidence was obtained by using immunohistochemistry with 5-HT receptor antibodies, which revealed expression of the 5-HT1A receptor but not other subtypes by migrating NC cells in both embryos and cranial NC explants. These results suggest that by activating appropriate receptors 5-HT may regulate migration of cranial NC cells and their mesenchymal derivatives in the mouse embryo. Images Fig. 1 Fig. 2 Fig. 3 PMID:7638165

  18. Restriction of neural precursor ability to respond to Nurr1 by early regional specification.

    PubMed

    Soldati, Chiara; Cacci, Emanuele; Biagioni, Stefano; Carucci, Nicoletta; Lupo, Giuseppe; Perrone-Capano, Carla; Saggio, Isabella; Augusti-Tocco, Gabriella

    2012-01-01

    During neural development, spatially regulated expression of specific transcription factors is crucial for central nervous system (CNS) regionalization, generation of neural precursors (NPs) and subsequent differentiation of specific cell types within defined regions. A critical role in dopaminergic differentiation in the midbrain (MB) has been assigned to the transcription factor Nurr1. Nurr1 controls the expression of key genes involved in dopamine (DA) neurotransmission, e.g. tyrosine hydroxylase (TH) and the DA transporter (DAT), and promotes the dopaminergic phenotype in embryonic stem cells. We investigated whether cells derived from different areas of the mouse CNS could be directed to differentiate into dopaminergic neurons in vitro by forced expression of the transcription factor Nurr1. We show that Nurr1 overexpression can promote dopaminergic cell fate specification only in NPs obtained from E13.5 ganglionic eminence (GE) and MB, but not in NPs isolated from E13.5 cortex (CTX) and spinal cord (SC) or from the adult subventricular zone (SVZ). Confirming previous studies, we also show that Nurr1 overexpression can increase the generation of TH-positive neurons in mouse embryonic stem cells. These data show that Nurr1 ability to induce a dopaminergic phenotype becomes restricted during CNS development and is critically dependent on the region of NPs derivation. Our results suggest that the plasticity of NPs and their ability to activate a dopaminergic differentiation program in response to Nurr1 is regulated during early stages of neurogenesis, possibly through mechanisms controlling CNS regionalization. PMID:23240065

  19. Restriction of Neural Precursor Ability to Respond to Nurr1 by Early Regional Specification

    PubMed Central

    Soldati, Chiara; Cacci, Emanuele; Biagioni, Stefano; Carucci, Nicoletta; Lupo, Giuseppe; Perrone-Capano, Carla; Saggio, Isabella; Augusti-Tocco, Gabriella

    2012-01-01

    During neural development, spatially regulated expression of specific transcription factors is crucial for central nervous system (CNS) regionalization, generation of neural precursors (NPs) and subsequent differentiation of specific cell types within defined regions. A critical role in dopaminergic differentiation in the midbrain (MB) has been assigned to the transcription factor Nurr1. Nurr1 controls the expression of key genes involved in dopamine (DA) neurotransmission, e.g. tyrosine hydroxylase (TH) and the DA transporter (DAT), and promotes the dopaminergic phenotype in embryonic stem cells. We investigated whether cells derived from different areas of the mouse CNS could be directed to differentiate into dopaminergic neurons in vitro by forced expression of the transcription factor Nurr1. We show that Nurr1 overexpression can promote dopaminergic cell fate specification only in NPs obtained from E13.5 ganglionic eminence (GE) and MB, but not in NPs isolated from E13.5 cortex (CTX) and spinal cord (SC) or from the adult subventricular zone (SVZ). Confirming previous studies, we also show that Nurr1 overexpression can increase the generation of TH-positive neurons in mouse embryonic stem cells. These data show that Nurr1 ability to induce a dopaminergic phenotype becomes restricted during CNS development and is critically dependent on the region of NPs derivation. Our results suggest that the plasticity of NPs and their ability to activate a dopaminergic differentiation program in response to Nurr1 is regulated during early stages of neurogenesis, possibly through mechanisms controlling CNS regionalization. PMID:23240065

  20. Endogenous neural precursors influence grafted neural stem cells and contribute to neuroprotection in the Parkinsonian rat

    PubMed Central

    Madhavan, Lalitha; Daley, Brian F; Sortwell, Caryl E; Collier, Timothy J

    2012-01-01

    Neuroprotective and neurorescue effects after neural stem/precursor cell (NPC) transplantation have been reported, but the mechanisms underlying such phenomena are not well understood. Our recent findings in a rat Parkinson’s disease (PD) model indicate that transplantation of NPCs before a 6-hydroxydopamine (6-OHDA) insult can result in nigrostriatal protection which is associated with endogenous NPC proliferation, migration and neurogenesis. Here, we sought to determine whether the observed endogenous NPC response (1) contributes to transplanted NPC - mediated neuroprotection and/or (2) affects graft phenotype and function. Host Fischer 344 rats were administered the antimitotic agent cytosine-β-D-arabinofuranoside (Ara-C) to eliminate actively proliferating endogenous neural precursors before being transplanted with NPCs and treated with 6-OHDA to induce nigrostriatal degeneration. Behavioral and histological analyses demonstrate that the neuroprotective response observed in NPC transplanted animals which had not received Ara-C was significantly attenuated in animals which did receive pre-transplant Ara-C. Also, while grafts in Ara-C treated animals showed no decrease in cell number, they exhibited significantly reduced expression of the neural stem cell regulators nestin and sonic hedgehog. In addition, inhibition of the endogenous NPC response resulted in an exaggerated host glial reaction. Overall, the study establishes for the first time that endogenous NPCs contribute to transplanted NPC-mediated therapeutic effects by affecting both grafted and mature host cells in unique ways. Thus, both endogenous and transplanted NPCs are important in creating an environment suitable for neural protection and rescue, and harnessing their synergistic interaction may lead to the optimization of cell-based therapies for PD. PMID:22417168

  1. Timeline and distribution of melanocyte precursors in the mouse heart.

    PubMed

    Brito, Flavia Carneiro; Kos, Lidia

    2008-08-01

    Apart from the well-studied melanocytes of the skin, eye and inner ear, another population has recently been described in the heart. In this study, we tracked cardiac melanoblasts using in situ hybridization with a dopachrome tautomerase (Dct) probe and Dct-LacZ transgenic mice. Large numbers of melanoblasts were found in the atrioventricular (AV) endocardial cushions at embryonic day (E) 14.5 and persisted in the AV valves into adulthood. The earliest time Dct-LacZ-positive cells were observed in the AV endocardial cushions was E12.5. Prior to that, between E10.5 and E11.5, small numbers of melanoblasts traveled between the post-otic area and third somite along the anterior and common cardinal veins and branchial arch arteries with other neural crest cells expressing CRABPI. Cardiac melanocytes were not found in the spotting mutants Ednrb s-l/s-l and Kit w-v/w-v, while large numbers were observed in transgenic mice that overexpress endothelin 3. These results indicate that cardiac melanocytes depend on the same signaling molecules known to be required for proper skin melanocyte development and may originate from the same precursor population. Cardiac melanocytes were not found in zebrafish or frog but were present in quail suggesting an association between cardiac melanocytes and four-chambered hearts. PMID:18444965

  2. Generation of Dopamine Neurons from Rodent Fibroblasts through the Expandable Neural Precursor Cell Stage*

    PubMed Central

    Lim, Mi-Sun; Chang, Mi-Yoon; Kim, Sang-Mi; Yi, Sang-Hoon; Suh-Kim, Haeyoung; Jung, Sung Jun; Kim, Min Jung; Kim, Jin Hyuk; Lee, Yong-Sung; Lee, Soo Young; Kim, Dong-Wook; Lee, Sang-Hun; Park, Chang-Hwan

    2015-01-01

    Recent groundbreaking work has demonstrated that combined expression of the transcription factors Brn2, Ascl1, and Myt1L (BAM; also known as Wernig factors) convert mouse fibroblasts into postmitotic neuronal cells. However, questions remain regarding whether trans-conversion is achieved directly or involves an intermediary precursor stage. Trans-conversion toward expandable neural precursor cells (NPCs) is more useful than direct one-step neuron formation with respect to yielding a sufficient number of cells and the feasibility of manipulating NPC differentiation toward certain neuron subtypes. Here, we show that co-expression of Wernig factors and Bcl-xL induces fibroblast conversion into NPCs (induced NPCs (iNPCs)) that are highly expandable for >100 passages. Gene expression analyses showed that the iNPCs exhibited high expression of common NPC genes but not genes specific to defined embryonic brain regions. This finding indicated that a regional identity of iNPCs was not established. Upon induction, iNPCs predominantly differentiated into astrocytes. However, the differentiation potential was not fixed and could be efficiently manipulated into general or specific subtypes of neurons by expression of additional genes. Specifically, overexpression of Nurr1 and Foxa2, transcription factors specific for midbrain dopamine neuron development, drove iNPCs to yield mature midbrain dopamine neurons equipped with presynaptic DA neuronal functions. We further assessed the therapeutic potential of iNPCs in Parkinson disease model rats. PMID:26023233

  3. Snail Coordinately Regulates Downstream Pathways to Control Multiple Aspects of Mammalian Neural Precursor Development

    PubMed Central

    Zander, Mark A.; Burns, Sarah E.; Yang, Guang; Kaplan, David R.

    2014-01-01

    The Snail transcription factor plays a key role in regulating diverse developmental processes but is not thought to play a role in mammalian neural precursors. Here, we have examined radial glial precursor cells of the embryonic murine cortex and demonstrate that Snail regulates their survival, self-renewal, and differentiation into intermediate progenitors and neurons via two distinct and separable target pathways. First, Snail promotes cell survival by antagonizing a p53-dependent death pathway because coincident p53 knockdown rescues survival deficits caused by Snail knockdown. Second, we show that the cell cycle phosphatase Cdc25b is regulated by Snail in radial precursors and that Cdc25b coexpression is sufficient to rescue the decreased radial precursor proliferation and differentiation observed upon Snail knockdown. Thus, Snail acts via p53 and Cdc25b to coordinately regulate multiple aspects of mammalian embryonic neural precursor biology. PMID:24719096

  4. Regulation of mouse embryonic stem cell neural differentiation by retinoic acid

    PubMed Central

    Kim, Mijeong; Habiba, Ayman; Doherty, Jason M.; Mills, Jason C.; Mercer, Robert W.; Huettner, James E.

    2009-01-01

    Pluripotent mouse embryonic stem cells (ESCs) derived from the early blastocyst can differentiate in vitro into a variety of somatic cell types including lineages from all three embryonic germ layers. Protocols for ES cell neural differentiation typically involve induction by retinoic acid (RA), or by exposure to growth factors or medium conditioned by other cell types. A serum-free differentiation (SFD) medium completely lacking exogenous retinoids was devised that allows for efficient conversion of aggregated mouse ESCs into neural precursors and immature neurons. Neural cells produced in this medium express neuronal ion channels, establish polarity, and form functional excitatory and inhibitory synapses. Brief exposure to RA during the period of cell aggregation speeds neuronal maturation and suppresses cell proliferation. Differentiation without RA yields neurons and neural progenitors with apparent telencephalic identity, whereas cells differentiated with exposure to RA express markers of hindbrain and spinal cord. Transcriptional profiling indicates a substantial representation of transit amplifying neuroblasts in SFD cultures not exposed to RA. PMID:19217899

  5. Differential Apoptosis Radiosensitivity of Neural Progenitors in Adult Mouse Hippocampus.

    PubMed

    Li, Yu-Qing; Cheng, Zoey; Wong, Shun

    2016-01-01

    Mammalian tissue-specific stem cells and progenitors demonstrate differential DNA damage response. Neural progenitors in dentate gyrus of the hippocampus are known to undergo apoptosis after irradiation. Using a mouse model of hippocampal neuronal development, we characterized the apoptosis sensitivity of the different neural progenitor subpopulations in adult mouse dentate gyrus after irradiation. Two different bromodeoxyuridine incorporation paradigms were used for cell fate mapping. We identified two apoptosis sensitive neural progenitor subpopulations after irradiation. The first represented non-proliferative and non-newborn neuroblasts and immature neurons that expressed doublecortin, calretinin or both. The second consisted of proliferative intermediate neural progenitors. The putative radial glia-like neural stem cells or type-1 cells, regardless of proliferation status, were apoptosis resistant after irradiation. There was no evidence of radiation-induced apoptosis in the absence of the Trp53 (p53) gene but absence of Cdkn1a (p21) did not alter the apoptotic response. Upregulation of nuclear p53 was observed in neuroblasts after irradiation. We conclude that adult hippocampal neural progenitors may demonstrate differential p53-dependent apoptosis sensitivity after irradiation. PMID:27331809

  6. Differential Apoptosis Radiosensitivity of Neural Progenitors in Adult Mouse Hippocampus

    PubMed Central

    Li, Yu-Qing; Cheng, Zoey; Wong, Shun

    2016-01-01

    Mammalian tissue-specific stem cells and progenitors demonstrate differential DNA damage response. Neural progenitors in dentate gyrus of the hippocampus are known to undergo apoptosis after irradiation. Using a mouse model of hippocampal neuronal development, we characterized the apoptosis sensitivity of the different neural progenitor subpopulations in adult mouse dentate gyrus after irradiation. Two different bromodeoxyuridine incorporation paradigms were used for cell fate mapping. We identified two apoptosis sensitive neural progenitor subpopulations after irradiation. The first represented non-proliferative and non-newborn neuroblasts and immature neurons that expressed doublecortin, calretinin or both. The second consisted of proliferative intermediate neural progenitors. The putative radial glia-like neural stem cells or type-1 cells, regardless of proliferation status, were apoptosis resistant after irradiation. There was no evidence of radiation-induced apoptosis in the absence of the Trp53 (p53) gene but absence of Cdkn1a (p21) did not alter the apoptotic response. Upregulation of nuclear p53 was observed in neuroblasts after irradiation. We conclude that adult hippocampal neural progenitors may demonstrate differential p53-dependent apoptosis sensitivity after irradiation. PMID:27331809

  7. Human embryonic stem cell differentiation toward regional specific neural precursors.

    PubMed

    Erceg, Slaven; Ronaghi, Mohammad; Stojković, Miodrag

    2009-01-01

    Human embryonic stem cells (hESCs) are self-renewing pluripotent cells that have the capacity to differentiate into a wide variety of cell types. This potentiality represents a promising source to overcome many human diseases by providing an unlimited supply of all cell types, including cells with neural characteristics. Therefore, this review summarizes early neural development and the potential of hESCs to differentiate under in vitro conditions, examining at the same time the potential use of differentiated hESCs for therapeutic applications for neural tissue and cell regeneration. PMID:18845761

  8. Human Embryonic Stem Cell Differentiation Toward Regional Specific Neural Precursors

    PubMed Central

    Erceg, Slaven; Ronaghi, Mohammad; Stojković, Miodrag

    2009-01-01

    Human embryonic stem cells (hESCs) are self-renewing pluripotent cells that have the capacity to differentiate into a wide variety of cell types. This potentiality represents a promising source to overcome many human diseases by providing an unlimited supply of all cell types, including cells with neural characteristics. Therefore, this review summarizes early neural development and the potential of hESCs to differentiate under in vitro conditions, examining at the same time the potential use of differentiated hESCs for therapeutic applications for neural tissue and cell regeneration. PMID:18845761

  9. Skin-derived neural precursors competitively generate functional myelin in adult demyelinated mice

    PubMed Central

    Mozafari, Sabah; Laterza, Cecilia; Roussel, Delphine; Bachelin, Corinne; Marteyn, Antoine; Deboux, Cyrille; Martino, Gianvito; Evercooren, Anne Baron-Van

    2015-01-01

    Induced pluripotent stem cell–derived (iPS-derived) neural precursor cells may represent the ideal autologous cell source for cell-based therapy to promote remyelination and neuroprotection in myelin diseases. So far, the therapeutic potential of reprogrammed cells has been evaluated in neonatal demyelinating models. However, the repair efficacy and safety of these cells has not been well addressed in the demyelinated adult CNS, which has decreased cell plasticity and scarring. Moreover, it is not clear if these induced pluripotent–derived cells have the same reparative capacity as physiologically committed CNS-derived precursors. Here, we performed a side-by-side comparison of CNS-derived and skin-derived neural precursors in culture and following engraftment in murine models of adult spinal cord demyelination. Grafted induced neural precursors exhibited a high capacity for survival, safe integration, migration, and timely differentiation into mature bona fide oligodendrocytes. Moreover, grafted skin–derived neural precursors generated compact myelin around host axons and restored nodes of Ranvier and conduction velocity as efficiently as CNS-derived precursors while outcompeting endogenous cells. Together, these results provide important insights into the biology of reprogrammed cells in adult demyelinating conditions and support use of these cells for regenerative biomedicine of myelin diseases that affect the adult CNS. PMID:26301815

  10. Impaired Neural Differentiation of Induced Pluripotent Stem Cells Generated from a Mouse Model of Sandhoff Disease

    PubMed Central

    Ogawa, Yasuhiro; Tanaka, Makoto; Tanabe, Miho; Suzuki, Toshihiro; Togawa, Tadayasu; Fukushige, Tomoko; Kanekura, Takuro; Sakuraba, Hitoshi; Oishi, Kazuhiko

    2013-01-01

    Sandhoff disease (SD) is a glycosphingolipid storage disease that arises from mutations in the Hexb gene and the resultant deficiency in β-hexosaminidase activity. This deficiency results in aberrant lysosomal accumulation of the ganglioside GM2 and related glycolipids, and progressive deterioration of the central nervous system. Dysfunctional glycolipid storage causes severe neurodegeneration through a poorly understood pathogenic mechanism. Induced pluripotent stem cell (iPSC) technology offers new opportunities for both elucidation of the pathogenesis of diseases and the development of stem cell-based therapies. Here, we report the generation of disease-specific iPSCs from a mouse model of SD. These mouse model-derived iPSCs (SD-iPSCs) exhibited pluripotent stem cell properties and significant accumulation of GM2 ganglioside. In lineage-directed differentiation studies using the stromal cell-derived inducing activity method, SD-iPSCs showed an impaired ability to differentiate into early stage neural precursors. Moreover, fewer neurons differentiated from neural precursors in SD-iPSCs than in the case of the wild type. Recovery of the Hexb gene in SD-iPSCs improved this impairment of neuronal differentiation. These results provide new insights as to understanding the complex pathogenic mechanisms of SD. PMID:23383290

  11. MiR-3099 is Overexpressed in Differentiating 46c Mouse Embryonic Stem Cells upon Neural Induction

    PubMed Central

    ZAINAL ABIDIN, Shahidee; ABBASPOURBABAEI, Maryam; NTIMI, Carolindah Makena; SIEW, Wei-Hong; Pike-See, CHEAH; ROSLI, Rozita; NORDIN, Norshariza; LING, King-Hwa

    2014-01-01

    Background: MicroRNAs (miRNAs) have a crucial role in gene expression regulation and protein synthesis, especially in the central nervous system. In developing mouse embryos a novel miRNA, miR-3099, is highly expressed, particularly in the central nervous system. This study aims to determine the expression of miR-3099 during cellular differentiation of 46C mouse embryonic stem cells after neural induction with N2/B27 medium. Methods: 46C mouse embryonic stem cells were subjected to neural induction with N2/B27 medium. At 0, 3, 7, 11, 17, and 22 days after neural induction, the cells were screened for various pluripotent, progenitor, and differentiating/differentiated cells markers by immunocytochemistry and reverse-transcriptase polymerase chain reaction (RT-PCR). Stem-loop pulse RT-PCR was performed to determine the expression of miR-3099 at all selected time points after neural induction. Results: Our findings showed that after induction, mouse embryonic stem cells differentiated into heterogeneous pools of cells containing neurons, astrocytes, and oligodendrocytes. Mouse embryonic stem cells and neural progenitor/precursor cells were also present in culture up to day 22 as indicated by RT-PCR analysis. Elucidation of miR-3099 expression during in vitro neural induction revealed that this miRNA was expressed throughout the differentiation process of 46C mouse embryonic stem cells. miR-3099 was expressed at higher levels on day 11, 17, and 22 as compared to day 0, 3 and 7 after neural induction. Conclusion: The level of miR-3099 expression was higher in differentiated mouse embryonic stem cells after neural induction. This finding suggested that miR-3099 might play a role in regulating neural stem cell differentiation. However, further characterisation of miR-3099 in a better characterised or optimised differentiated neural stem cell culture would provide increased understanding of the cellular function and molecular targets of miR-3099, especially in neuron

  12. Neural Mechanisms Contributing to Dysphagia in Mouse Models.

    PubMed

    Hinkel, Cameron J; Sharma, Rishi; Thakkar, Mahesh M; Takahashi, Kazutaka; Hopewell, Bridget L; Lever, Teresa E

    2016-08-01

    Investigative research into curative treatments for dysphagia is hindered by our incomplete understanding of the neural mechanisms of swallowing in health and disease. Development of translational research models is essential to bridge this knowledge gap by fostering innovative methodology. Toward this goal, our laboratory has developed a translational research assessment tool to investigate the neural mechanistic control of swallowing in unrestrained, self-feeding mice. Here we describe our initial development of synchronous brainstem neural recordings with a videofluoroscopic swallow study assay in healthy mice across the life span. Refinement of this combined methodology is currently underway. Ultimately, we envision that this assessment tool will permit systematic analysis of therapeutic interventions for dysphagia in preclinical trials with numerous mouse models of human conditions that cause dysphagia, such as amyotrophic lateral sclerosis, Parkinson's disease, stroke, and advanced aging. PMID:27048676

  13. Meninges harbor cells expressing neural precursor markers during development and adulthood

    PubMed Central

    Bifari, Francesco; Berton, Valeria; Pino, Annachiara; Kusalo, Marijana; Malpeli, Giorgio; Di Chio, Marzia; Bersan, Emanuela; Amato, Eliana; Scarpa, Aldo; Krampera, Mauro; Fumagalli, Guido; Decimo, Ilaria

    2015-01-01

    Brain and skull developments are tightly synchronized, allowing the cranial bones to dynamically adapt to the brain shape. At the brain-skull interface, meninges produce the trophic signals necessary for normal corticogenesis and bone development. Meninges harbor different cell populations, including cells forming the endosteum of the cranial vault. Recently, we and other groups have described the presence in meninges of a cell population endowed with neural differentiation potential in vitro and, after transplantation, in vivo. However, whether meninges may be a niche for neural progenitor cells during embryonic development and in adulthood remains to be determined. In this work we provide the first description of the distribution of neural precursor markers in rat meninges during development up to adulthood. We conclude that meninges share common properties with the classical neural stem cell niche, as they: (i) are a highly proliferating tissue; (ii) host cells expressing neural precursor markers such as nestin, vimentin, Sox2 and doublecortin; and (iii) are enriched in extracellular matrix components (e.g., fractones) known to bind and concentrate growth factors. This study underlines the importance of meninges as a potential niche for endogenous precursor cells during development and in adulthood. PMID:26483637

  14. The amyloid precursor protein (APP) triplicated gene impairs neuronal precursor differentiation and neurite development through two different domains in the Ts65Dn mouse model for Down syndrome.

    PubMed

    Trazzi, Stefania; Fuchs, Claudia; Valli, Emanuele; Perini, Giovanni; Bartesaghi, Renata; Ciani, Elisabetta

    2013-07-19

    Intellectual disability in Down syndrome (DS) appears to be related to severe proliferation impairment during brain development. Recent evidence shows that it is not only cellular proliferation that is heavily compromised in DS, but also cell fate specification and dendritic maturation. The amyloid precursor protein (APP), a gene that is triplicated in DS, plays a key role in normal brain development by influencing neural precursor cell proliferation, cell fate specification, and neuronal maturation. APP influences these processes via two separate domains, the APP intracellular domain (AICD) and the soluble secreted APP. We recently found that the proliferation impairment of neuronal precursors (NPCs) from the Ts65Dn mouse model for DS was caused by derangement of the Shh pathway due to overexpression of patched1(Ptch1), its inhibitory regulator. Ptch1 overexpression was related to increased levels within the APP/AICD system. The overall goal of this study was to determine whether APP contributes to neurogenesis impairment in DS by influencing in addition to proliferation, cell fate specification, and neurite development. We found that normalization of APP expression restored the reduced neuronogenesis, the increased astrogliogenesis, and the reduced neurite length of trisomic NPCs, indicating that APP overexpression underpins all aspects of neurogenesis impairment. Moreover, we found that two different domains of APP impair neuronal differentiation and maturation in trisomic NPCs. The APP/AICD system regulates neuronogenesis and neurite length through the Shh pathway, whereas the APP/secreted AP system promotes astrogliogenesis through an IL-6-associated signaling cascade. These results provide novel insight into the mechanisms underlying brain development alterations in DS. PMID:23740250

  15. Glutathione peroxidase 4 prevents necroptosis in mouse erythroid precursors

    PubMed Central

    Canli, Özge; Alankuş, Yasemin B.; Grootjans, Sasker; Vegi, Naidu; Hültner, Lothar; Hoppe, Philipp S.; Schroeder, Timm; Vandenabeele, Peter; Bornkamm, Georg W.

    2016-01-01

    Maintaining cellular redox balance is vital for cell survival and tissue homoeostasis because imbalanced production of reactive oxygen species (ROS) may lead to oxidative stress and cell death. The antioxidant enzyme glutathione peroxidase 4 (Gpx4) is a key regulator of oxidative stress–induced cell death. We show that mice with deletion of Gpx4 in hematopoietic cells develop anemia and that Gpx4 is essential for preventing receptor-interacting protein 3 (RIP3)-dependent necroptosis in erythroid precursor cells. Absence of Gpx4 leads to functional inactivation of caspase 8 by glutathionylation, resulting in necroptosis, which occurs independently of tumor necrosis factor α activation. Although genetic ablation of Rip3 normalizes reticulocyte maturation and prevents anemia, ROS accumulation and lipid peroxidation in Gpx4-deficient cells remain high. Our results demonstrate that ROS and lipid hydroperoxides function as not-yet-recognized unconventional upstream signaling activators of RIP3-dependent necroptosis. PMID:26463424

  16. Enrichment of Oligodendrocyte Progenitors from Differentiated Neural Precursors by Clonal Sphere Preparations.

    PubMed

    Umebayashi, Daisuke; Coles, Brenda; van der Kooy, Derek

    2016-05-01

    Remyelination is the goal of potential cell transplantation therapies for demyelinating diseases and other central nervous system injuries. Transplantation of oligodendrocyte precursor cells (OPCs) can result in remyelination in the central nervous system, and induced pluripotent stem cells (iPSCs) are envisioned to be an autograft cell source of transplantation therapy for many cell types. However, it remains time-consuming and difficult to generate OPCs from iPSCs. Clonal sphere preparations are reliable cell culture methods for purifying select populations of proliferating cells. To make clonal neurospheres from human embryonic stem cell (ESC)/iPSC colonies, we have found that a monolayer differentiation phase helps to increase the numbers of neural precursor cells. Indeed, we have compared a direct isolation of neural stem cells from human ESC/iPSC colonies (protocol 1) with monolayer neural differentiation, followed by clonal neural stem cell sphere preparations (protocol 2). The two-step method combining monolayer neuralization, followed by clonal sphere preparations, is more useful than direct sphere preparations in generating mature human oligodendrocytes. The initial monolayer culture stage appears to bias cells toward the oligodendrocyte lineage. This method of deriving oligodendrocyte lineage spheres from iPSCs represents a novel strategy for generating OPCs. PMID:26972950

  17. Precursors predicted by artificial neural networks for mass balance calculations: Quantifying hydrothermal alteration in volcanic rocks

    NASA Astrophysics Data System (ADS)

    Trépanier, Sylvain; Mathieu, Lucie; Daigneault, Réal; Faure, Stéphane

    2016-04-01

    This study proposes an artificial neural networks-based method for predicting the unaltered (precursor) chemical compositions of hydrothermally altered volcanic rock. The method aims at predicting precursor's major components contents (SiO2, FeOT, MgO, CaO, Na2O, and K2O). The prediction is based on ratios of elements generally immobile during alteration processes; i.e. Zr, TiO2, Al2O3, Y, Nb, Th, and Cr, which are provided as inputs to the neural networks. Multi-layer perceptron neural networks were trained on a large dataset of least-altered volcanic rock samples that document a wide range of volcanic rock types, tectonic settings and ages. The precursors thus predicted are then used to perform mass balance calculations. Various statistics were calculated to validate the predictions of precursors' major components, which indicate that, overall, the predictions are precise and accurate. For example, rank-based correlation coefficients were calculated to compare predicted and analysed values from a least-altered test dataset that had not been used to train the networks. Coefficients over 0.87 were obtained for all components, except for Na2O (0.77), indicating that predictions for alkali might be less performant. Also, predictions are performant for most volcanic rock compositions, except for ultra-K rocks. The proposed method provides an easy and rapid solution to the often difficult task of determining appropriate volcanic precursor compositions to rocks modified by hydrothermal alteration. It is intended for large volcanic rock databases and is most useful, for example, to mineral exploration performed in complex or poorly known volcanic settings. The method is implemented as a simple C++ console program.

  18. Ibuprofen slows migration and inhibits bowel colonization by enteric nervous system precursors in zebrafish, chick and mouse.

    PubMed

    Schill, Ellen Merrick; Lake, Jonathan I; Tusheva, Olga A; Nagy, Nandor; Bery, Saya K; Foster, Lynne; Avetisyan, Marina; Johnson, Stephen L; Stenson, William F; Goldstein, Allan M; Heuckeroth, Robert O

    2016-01-15

    Hirschsprung Disease (HSCR) is a potentially deadly birth defect characterized by the absence of the enteric nervous system (ENS) in distal bowel. Although HSCR has clear genetic causes, no HSCR-associated mutation is 100% penetrant, suggesting gene-gene and gene-environment interactions determine HSCR occurrence. To test the hypothesis that certain medicines might alter HSCR risk we treated zebrafish with medications commonly used during early human pregnancy and discovered that ibuprofen caused HSCR-like absence of enteric neurons in distal bowel. Using fetal CF-1 mouse gut slice cultures, we found that ibuprofen treated enteric neural crest-derived cells (ENCDC) had reduced migration, fewer lamellipodia and lower levels of active RAC1/CDC42. Additionally, inhibiting ROCK, a RHOA effector and known RAC1 antagonist, reversed ibuprofen effects on migrating mouse ENCDC in culture. Ibuprofen also inhibited colonization of Ret+/- mouse bowel by ENCDC in vivo and dramatically reduced bowel colonization by chick ENCDC in culture. Interestingly, ibuprofen did not affect ENCDC migration until after at least three hours of exposure. Furthermore, mice deficient in Ptgs1 (COX 1) and Ptgs2 (COX 2) had normal bowel colonization by ENCDC and normal ENCDC migration in vitro suggesting COX-independent effects. Consistent with selective and strain specific effects on ENCDC, ibuprofen did not affect migration of gut mesenchymal cells, NIH3T3, or WT C57BL/6 ENCDC, and did not affect dorsal root ganglion cell precursor migration in zebrafish. Thus, ibuprofen inhibits ENCDC migration in vitro and bowel colonization by ENCDC in vivo in zebrafish, mouse and chick, but there are cell type and strain specific responses. These data raise concern that ibuprofen may increase Hirschsprung disease risk in some genetically susceptible children. PMID:26586201

  19. Long-term culture and differentiation of CNS precursors derived from anterior human neural rosettes following exposure to ventralizing factors

    SciTech Connect

    Colleoni, Silvia; Giannelli, Serena G.; Armentero, Marie-Therese; Blandini, Fabio; Broccoli, Vania; Lazzari, Giovanna

    2010-04-15

    In this study we demonstrated that neural rosettes derived from human ES cells can give rise either to neural crest precursors, following expansion in presence of bFGF and EGF, or to dopaminergic precursors after exposure to ventralizing factors Shh and FGF8. Both regionalised precursors are capable of extensive proliferation and differentiation towards the corresponding terminally differentiated cell types. In particular, peripheral neurons, cartilage, bone, smooth muscle cells and also pigmented cells were obtained from neural crest precursors while tyrosine hydroxylase and Nurr1 positive dopaminergic neurons were derived from FGF8 and Shh primed rosette cells. Gene expression and immunocytochemistry analyses confirmed the expression of dorsal and neural crest genes such as Sox10, Slug, p75, FoxD3, Pax7 in neural precursors from bFGF-EGF exposed rosettes. By contrast, priming of rosettes with FGF8 and Shh induced the expression of dopaminergic markers Engrailed1, Pax2, Pitx3, floor plate marker FoxA2 and radial glia markers Blbp and Glast, the latter in agreement with the origin of dopaminergic precursors from floor plate radial glia. Moreover, in vivo transplant of proliferating Shh/FGF8 primed precursors in parkinsonian rats demonstrated engraftment and terminal dopaminergic differentiation. In conclusion, we demonstrated the derivation of long-term self-renewing precursors of selected regional identity as potential cell reservoirs for cell therapy applications, such as CNS degenerative diseases, or for the development of toxicological tests.

  20. Krabbe disease: involvement of connexin43 in the apoptotic effects of sphingolipid psychosine on mouse oligodendrocyte precursors.

    PubMed

    Graziano, A C E; Parenti, R; Avola, R; Cardile, V

    2016-01-01

    Krabbe disease is a genetic demyelinating syndrome characterized by deficiency of the enzyme β-galactosylceramidase, lysosomal psychosine accumulation, and loss of myelin-forming cells. In this study, some apoptotic markers such as apoptotic index (AI), DNA fragmentation, caspase-3, PTEN, Bad, and PI3K were determined in oligodendrocyte precursors from wild type or twitcher mice untreated or treated with psychosine. Twitcher is a natural mouse model of Krabbe disease containing a premature stop codon (W339X) in the β-galactosylceramidase gene. Moreover, a possible involvement of connexin (Cx)43 in cell death of oligodendrocyte precursors induced by psychosine was investigated with the final aim to provide a contribution to the knowledge of the molecular mechanisms and pathophysiological events that occur in Krabbe disease. Connexins are a multigene family of structurally related trans-membrane proteins able to modulate essential cellular processes such as proliferation, differentiation and migration. Among these, Cx43 is the predominant isoform in many cell types, including neural progenitor cells. Our results showed an increase of AI, DNA fragmentation, caspase-3, PTEN, Bad, and Cx43 associated to a decrease of PI3K, pAKT and pBad. Taken together, these findings suggest an involvement of Cx43 in the psychosine-mediated apoptosis of primary oligodendrocyte progenitors from wild type or twitcher mice, used for the first time as cell models in comparison. It could open unexplored perspective also for other demyelinating diseases. PMID:26459425

  1. Mouse models of neural tube defects: investigating preventive mechanisms.

    PubMed

    Greene, Nicholas D E; Copp, Andrew J

    2005-05-15

    Neural tube defects (NTD), including anencephaly and spina bifida, are a group of severe congenital abnormalities in which the future brain and/or spinal cord fail to close. In mice, NTD may result from genetic mutations or knockouts, or from exposure to teratogenic agents, several of which are known risk factors in humans. Among the many mouse NTD models that have been identified to date, a number have been tested for possible primary prevention of NTD by exogenous agents, such as folic acid. In genetic NTD models such as Cart1, splotch, Cited2, and crooked tail, and NTD induced by teratogens including valproic acid and fumonisins, the incidence of defects is reduced by maternal folic acid supplementation. These folate-responsive models provide an opportunity to investigate the possible mechanisms underlying prevention of NTD by folic acid in humans. In another group of mouse models, that includes curly tail, axial defects, and the Ephrin-A5 knockout, NTD are not preventable by folic acid, reflecting the situation in humans in which a subset of NTD appear resistant to folic acid therapy. In this group of mutants alternative preventive agents, including inositol and methionine, have been shown to be effective. Overall, the data from mouse models suggests that a broad-based in utero therapy may offer scope for prevention of a greater proportion of NTD than is currently possible. PMID:15800852

  2. Astrocyte-Secreted Factors Selectively Alter Neural Stem and Progenitor Cell Proliferation in the Fragile X Mouse

    PubMed Central

    Sourial, Mary; Doering, Laurie C.

    2016-01-01

    An increasing body of evidence indicates that astrocytes contribute to the governance and fine tuning of stem and progenitor cell production during brain development. The effect of astrocyte function in cell production in neurodevelopmental disorders is unknown. We used the Neural Colony Forming Cell assay to determine the effect of astrocyte conditioned media (ACM) on the generation of neurospheres originating from either progenitor cells or functional stem cells in the knock out (KO) Fragile X mouse model. ACM from both normal and Fmr1-KO mice generated higher percentages of smaller neurospheres indicative of restricted proliferation of the progenitor cell population in Fmr1-KO brains. Wild type (WT) neurospheres, but not KO neurospheres, showed enhanced responses to ACM from the Fmr1-KO mice. In particular, Fmr1-KO ACM increased the percentage of large neurospheres generated, representative of spheres produced from neural stem cells. We also used 2D DIGE to initiate identification of the astrocyte-secreted proteins with differential expression between Fmr1-KO and WT cortices and hippocampi. The results further support the critical role of astrocytes in governing neural cell production in brain development and point to significant alterations in neural cell proliferation due to astrocyte secreted factors from the Fragile X brain. Highlights: • We studied the proliferation of neural stem and progenitor cells in Fragile X. • We examined the role of astrocyte-secreted factors in neural precursor cell biology. • Astrocyte-secreted factors with differential expression in Fragile X identified. PMID:27242437

  3. Lack of Motor Neuron Differentiation is an Intrinsic Property of the Mouse Secondary Neural Tube

    PubMed Central

    Shum, Alisa S.W.; Tang, Louisa S.C.; Copp, Andrew J.; Roelink, Henk

    2016-01-01

    The cranial part of the amniote neural tube is formed by folding and fusion of the ectoderm-derived neural plate (primary neurulation). After posterior neuropore closure, however, the caudal neural tube is formed by cavitation of tail bud mesenchyme (secondary neurulation). In mouse embryos, the secondary neural tube expresses several genes important in early patterning and induction, in restricted domains similar to the primary neural tube, yet it does not undergo neuronal differentiation, but subsequently degenerates. Although the secondary neural tube, isolated from surrounding tissues, is responsive to exogenous Sonic Hedgehog proteins in vitro, motor neuron differentiation is never observed. This cannot be attributed to the properties of the secondary notochord, since it is able to induce motor neuron differentiation in naïve chick neural plate explants. Taken together, these results support that the lack of motor neuron differentiation is an intrinsic property of the mouse secondary neural tube. PMID:20960561

  4. Long-term survival and integration of porcine expanded neural precursor cell grafts in a rat model of Parkinson's disease.

    PubMed

    Harrower, T P; Tyers, P; Hooks, Y; Barker, R A

    2006-01-01

    Porcine fetal neural tissue has been considered as an alternative source to human allografts for transplantation in neurodegenerative disorders by virtue of the fact that it can overcome the ethical and practical difficulties using human fetal neural tissue. However, primary porcine neural xenografts are rejected while porcine expanded neural precursor neural cells (PNPCs) seem to be less immunogenic and thus survive better [Armstrong, R.J., Harrower, T.P., Hurelbrink, C.B., McLaughin, M., Ratcliffe, E.L., Tyers, P., Richards, A., Dunnett, S.B., Rosser, A.E., Barker, R.A., 2001a. Porcine neural xenografts in the immunocompetent rat: immune response following grafting of expanded neural precursor cells. Neuroscience 106, 201-216]. In this study, we extended these observations to investigate the long-term survival of such transplants in immunosuppressed rats. Unilateral 6 OHDA lesioned rats received grafts into the dopamine denervated striatum of either primary porcine fetal neural tissue dissected from the E26 cortex or cortically derived neural stem cells which had been derived from the same source but expanded in vitro for 21 days. All cortically derived neural stem cell grafts survived up to 5 months in contrast to the poor survival of primary porcine xenografts. Histological analysis demonstrated good graft integration with fibers extending into the surrounding host tissue including white matter with synapse formation, and in addition there was evidence of host vascularization and myelinated fibers within the graft area. This study has therefore shown for the first time the reliable long-term survival of grafts derived from porcine expanded neural precursors in a rat model of PD, with maturation and integration into the host brain. This demonstrates that such xenografted cells may be able to recreate the damaged circuitry in PD although strategies for dopaminergic differentiation of the porcine neural precursor cell remain to be refined. PMID:16246328

  5. Early Divergence of Central and Peripheral Neural Retina Precursors During Vertebrate Eye Development

    PubMed Central

    Venters, Sara J.; Mikawa, Takashi; Hyer, Jeanette

    2015-01-01

    During development of the vertebrate eye, optic tissue is progressively compartmentalized into functionally distinct tissues. From the central to the peripheral optic cup, the original optic neuroepithelial tissue compartmentalizes, forming retina, ciliary body and iris. The retina can be further sub-divided into peripheral and central compartments, where the central domain is specialized for higher visual acuity, having a higher ratio and density of cone photoreceptors in most species. Classically, models depict a segregation of the early optic cup into only two domains, neural and non-neural. Recent studies, however, uncovered discrete precursors for central and peripheral retina in the optic vesicle, indicating that the neural retina cannot be considered as a single unit with homogeneous specification and development. Instead, central and peripheral retina may be subject to distinct developmental pathways that underlie their specialization. This review focuses on lineage relationships in the retina and revisits the historical context for segregation of central and peripheral retina precursors before overt eye morphogenesis. PMID:25329498

  6. Inhibition of glycogen synthase kinase-3 enhances the differentiation and reduces the proliferation of adult human olfactory epithelium neural precursors

    SciTech Connect

    Manceur, Aziza P.; Tseng, Michael; Holowacz, Tamara; Witterick, Ian; Weksberg, Rosanna; McCurdy, Richard D.; Warsh, Jerry J.; Audet, Julie

    2011-09-10

    The olfactory epithelium (OE) contains neural precursor cells which can be easily harvested from a minimally invasive nasal biopsy, making them a valuable cell source to study human neural cell lineages in health and disease. Glycogen synthase kinase-3 (GSK-3) has been implicated in the etiology and treatment of neuropsychiatric disorders and also in the regulation of murine neural precursor cell fate in vitro and in vivo. In this study, we examined the impact of decreased GSK-3 activity on the fate of adult human OE neural precursors in vitro. GSK-3 inhibition was achieved using ATP-competitive (6-bromoindirubin-3'-oxime and CHIR99021) or substrate-competitive (TAT-eIF2B) inhibitors to eliminate potential confounding effects on cell fate due to off-target kinase inhibition. GSK-3 inhibitors decreased the number of neural precursor cells in OE cell cultures through a reduction in proliferation. Decreased proliferation was not associated with a reduction in cell survival but was accompanied by a reduction in nestin expression and a substantial increase in the expression of the neuronal differentiation markers MAP1B and neurofilament (NF-M) after 10 days in culture. Taken together, these results suggest that GSK-3 inhibition promotes the early stages of neuronal differentiation in cultures of adult human neural precursors and provide insights into the mechanisms by which alterations in GSK-3 signaling affect adult human neurogenesis, a cellular process strongly suspected to play a role in the etiology of neuropsychiatric disorders.

  7. CBP regulates the differentiation of interneurons from ventral forebrain neural precursors during murine development.

    PubMed

    Tsui, David; Voronova, Anastassia; Gallagher, Denis; Kaplan, David R; Miller, Freda D; Wang, Jing

    2014-01-15

    The mechanisms that regulate appropriate genesis and differentiation of interneurons in the developing mammalian brain are of significant interest not only because interneurons play key roles in the establishment of neural circuitry, but also because when they are deficient, this can cause epilepsy. In this regard, one genetic syndrome that is associated with deficits in neural development and epilepsy is Rubinstein-Taybi Syndrome (RTS), where the transcriptional activator and histone acetyltransferase CBP is mutated and haploinsufficient. Here, we have asked whether CBP is necessary for the appropriate genesis and differentiation of interneurons in the murine forebrain, since this could provide an explanation for the epilepsy that is associated with RTS. We show that CBP is expressed in neural precursors within the embryonic medial ganglionic eminence (MGE), an area that generates the vast majority of interneurons for the cortex. Using primary cultures of MGE precursors, we show that knockdown of CBP causes deficits in differentiation of these precursors into interneurons and oligodendrocytes, and that overexpression of CBP is by itself sufficient to enhance interneuron genesis. Moreover, we show that levels of the neurotransmitter synthesis enzyme GAD67, which is expressed in inhibitory interneurons, are decreased in the dorsal and ventral forebrain of neonatal CBP(+/-) mice, indicating that CBP plays a role in regulating interneuron development in vivo. Thus, CBP normally acts to ensure the differentiation of appropriate numbers of forebrain interneurons, and when its levels are decreased, this causes deficits in interneuron development, providing a potential explanation for the epilepsy seen in individuals with RTS. PMID:24247009

  8. Coculture with endothelial cells reduces the population of cycling LeX neural precursors but increases that of quiescent cells with a side population phenotype

    SciTech Connect

    Mathieu, Celine . E-mail: marc-andre.mouthon@cea.fr

    2006-04-01

    Neural stem cell proliferation and differentiation are regulated by external cues from their microenvironment. As endothelial cells are closely associated with neural stem cell in brain germinal zones, we investigated whether endothelial cells may interfere with neurogenesis. Neural precursor cells (NPC) from telencephalon of EGFP mouse embryos were cocultured in direct contact with endothelial cells. Endothelial cells did not modify the overall proliferation and apoptosis of neural cells, albeit they transiently delayed spontaneous apoptosis. These effects appeared to be specific to endothelial cells since a decrease in proliferation and a raise in apoptosis were observed in cocultures with fibroblasts. Endothelial cells stimulated the differentiation of NPC into astrocytes and into neurons, whereas they reduced differentiation into oligodendrocytes in comparison to adherent cultures on polyornithine. Determination of NPC clonogenicity and quantification of LeX expression, a marker for NPC, showed that endothelial cells decreased the number of cycling NPC. On the other hand, the presence of endothelial cells increased the number of neural cells having 'side population' phenotype, another marker reported on NPC, which we have shown to contain quiescent cells. Thus, we show that endothelial cells may regulate neurogenesis by acting at different level of NPC differentiation, proliferation and quiescence.

  9. A study on precursors leading to geomagnetic storms using artificial neural network

    NASA Astrophysics Data System (ADS)

    Singh, Gaurav; Singh, A. K.

    2016-06-01

    Space weather prediction involves advance forecasting of the magnitude and onset time of major geomagnetic storms on Earth. In this paper, we discuss the development of an artificial neural network-based model to study the precursor leading to intense and moderate geomagnetic storms, following halo coronal mass ejection (CME) and related interplanetary (IP) events. IP inputs were considered within a 5-day time window after the commencement of storm. The artificial neural network (ANN) model training, testing and validation datasets were constructed based on 110 halo CMEs (both full and partial halo and their properties) observed during the ascending phase of the 24th solar cycle between 2009 and 2014. The geomagnetic storm occurrence rate from halo CMEs is estimated at a probability of 79%, by this model.

  10. ETOH inhibits embryonic neural stem/precursor cell proliferation via PLD signaling

    SciTech Connect

    Fujita, Yuko; Hiroyama, Masami; Sanbe, Atsushi Yamauchi, Junji; Murase, Shoko; Tanoue, Akito

    2008-05-23

    While a mother's excessive alcohol consumption during pregnancy is known to have adverse effects on fetal neural development, little is known about the underlying mechanism of these effects. In order to investigate these mechanisms, we investigated the toxic effect of ethanol (ETOH) on neural stem/precursor cell (NSC) proliferation. In cultures of NSCs, phospholipase D (PLD) is activated following stimulation with epidermal growth factor (EGF) and fibroblast growth factor 2 (FGF2). Exposure of NSCs to ETOH suppresses cell proliferation, while it has no effect on cell death. Phosphatidic acid (PA), which is a signaling messenger produced by PLD, reverses ETOH inhibition of NSC proliferation. Blocking the PLD signal by 1-butanol suppresses the proliferation. ETOH-induced suppression of NSC proliferation and the protective effect of PA for ETOH-induced suppression are mediated through extracellular signal-regulated kinase signaling. These results indicate that exposure to ETOH impairs NSC proliferation by altering the PLD signaling pathway.

  11. A study on precursors leading to geomagnetic storms using artificial neural network

    NASA Astrophysics Data System (ADS)

    Singh, Gaurav; Singh, A. K.

    2016-07-01

    Space weather prediction involves advance forecasting of the magnitude and onset time of major geomagnetic storms on Earth. In this paper, we discuss the development of an artificial neural network-based model to study the precursor leading to intense and moderate geomagnetic storms, following halo coronal mass ejection (CME) and related interplanetary (IP) events. IP inputs were considered within a 5-day time window after the commencement of storm. The artificial neural network (ANN) model training, testing and validation datasets were constructed based on 110 halo CMEs (both full and partial halo and their properties) observed during the ascending phase of the 24th solar cycle between 2009 and 2014. The geomagnetic storm occurrence rate from halo CMEs is estimated at a probability of 79%, by this model.

  12. The role of neural precursor cells and self assembling peptides in nerve regeneration

    PubMed Central

    2013-01-01

    Objective Cranial nerve injury involves loss of central neural cells in the brain stem and surrounding support matrix, leading to severe functional impairment. Therapeutically targeting cellular replacement and enhancing structural support may promote neural regeneration. We examined the combinatorial effect of neural precursor cells (NPC) and self assembling peptide (SAP) administration on nerve regeneration. Methods Nerve injury was induced by clip compression of the rodent spinal cord. SAPs were injected immediately into the injured cord and NPCs at 2 weeks post-injury. Behavioral analysis was done weekly and rats were sacrificed at 11 weeks post injury. LFB-H&E staining was done on cord tissue to assess cavitation volume. Motor evoked potentials (MEP) were measured at week 11 to assess nerve conduction and Kaplan meier curves were created to compare survival estimates. Results NPCs and SAPs were distributed both caudal and rostral to the injury site. Behavioral analysis showed that SAP + NPC transplantation significantly improved locomotor score p <0.03) and enhanced survival (log rank test, p = 0.008) compared to control. SAP + NPC treatment also improved nerve conduction velocity (p = 0.008) but did not affect cavitation volume (p = 0.73). Conclusion Combinatorial NPC and SAP injection into injured nerve tissue may enhance neural repair and regeneration. PMID:24351041

  13. Rejuvenation of MPTP-induced human neural precursor cell senescence by activating autophagy

    SciTech Connect

    Zhu, Liang; Dong, Chuanming; Sun, Chenxi; Ma, Rongjie; Yang, Danjing; Zhu, Hongwen; Xu, Jun

    2015-08-21

    Aging of neural stem cell, which can affect brain homeostasis, may be caused by many cellular mechanisms. Autophagy dysfunction was found in aged and neurodegenerative brains. However, little is known about the relationship between autophagy and human neural stem cell (hNSC) aging. The present study used 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) to treat neural precursor cells (NPCs) derived from human embryonic stem cell (hESC) line H9 and investigate related molecular mechanisms involved in this process. MPTP-treated NPCs were found to undergo premature senescence [determined by increased senescence-associated-β-galactosidase (SA-β-gal) activity, elevated intracellular reactive oxygen species level, and decreased proliferation] and were associated with impaired autophagy. Additionally, the cellular senescence phenotypes were manifested at the molecular level by a significant increase in p21 and p53 expression, a decrease in SOD2 expression, and a decrease in expression of some key autophagy-related genes such as Atg5, Atg7, Atg12, and Beclin 1. Furthermore, we found that the senescence-like phenotype of MPTP-treated hNPCs was rejuvenated through treatment with a well-known autophagy enhancer rapamycin, which was blocked by suppression of essential autophagy gene Beclin 1. Taken together, these findings reveal the critical role of autophagy in the process of hNSC aging, and this process can be reversed by activating autophagy. - Highlights: • We successfully establish hESC-derived neural precursor cells. • MPTP treatment induced senescence-like state in hESC-derived NPCs. • MPTP treatment induced impaired autophagy of hESC-derived NPCs. • MPTP-induced hESC-derived NPC senescence was rejuvenated by activating autophagy.

  14. Pulsed DC Electric Field–Induced Differentiation of Cortical Neural Precursor Cells

    PubMed Central

    Chang, Hui-Fang; Lee, Ying-Shan; Tang, Tang K.; Cheng, Ji-Yen

    2016-01-01

    We report the differentiation of neural stem and progenitor cells solely induced by direct current (DC) pulses stimulation. Neural stem and progenitor cells in the adult mammalian brain are promising candidates for the development of therapeutic neuroregeneration strategies. The differentiation of neural stem and progenitor cells depends on various in vivo environmental factors, such as nerve growth factor and endogenous EF. In this study, we demonstrated that the morphologic and phenotypic changes of mouse neural stem and progenitor cells (mNPCs) could be induced solely by exposure to square-wave DC pulses (magnitude 300 mV/mm at frequency of 100-Hz). The DC pulse stimulation was conducted for 48 h, and the morphologic changes of mNPCs were monitored continuously. The length of primary processes and the amount of branching significantly increased after stimulation by DC pulses for 48 h. After DC pulse treatment, the mNPCs differentiated into neurons, astrocytes, and oligodendrocytes simultaneously in stem cell maintenance medium. Our results suggest that simple DC pulse treatment could control the fate of NPCs. With further studies, DC pulses may be applied to manipulate NPC differentiation and may be used for the development of therapeutic strategies that employ NPCs to treat nervous system disorders. PMID:27352251

  15. Pulsed DC Electric Field-Induced Differentiation of Cortical Neural Precursor Cells.

    PubMed

    Chang, Hui-Fang; Lee, Ying-Shan; Tang, Tang K; Cheng, Ji-Yen

    2016-01-01

    We report the differentiation of neural stem and progenitor cells solely induced by direct current (DC) pulses stimulation. Neural stem and progenitor cells in the adult mammalian brain are promising candidates for the development of therapeutic neuroregeneration strategies. The differentiation of neural stem and progenitor cells depends on various in vivo environmental factors, such as nerve growth factor and endogenous EF. In this study, we demonstrated that the morphologic and phenotypic changes of mouse neural stem and progenitor cells (mNPCs) could be induced solely by exposure to square-wave DC pulses (magnitude 300 mV/mm at frequency of 100-Hz). The DC pulse stimulation was conducted for 48 h, and the morphologic changes of mNPCs were monitored continuously. The length of primary processes and the amount of branching significantly increased after stimulation by DC pulses for 48 h. After DC pulse treatment, the mNPCs differentiated into neurons, astrocytes, and oligodendrocytes simultaneously in stem cell maintenance medium. Our results suggest that simple DC pulse treatment could control the fate of NPCs. With further studies, DC pulses may be applied to manipulate NPC differentiation and may be used for the development of therapeutic strategies that employ NPCs to treat nervous system disorders. PMID:27352251

  16. Signaling through three chemokine receptors triggers the migration of transplanted neural precursor cells in a model of multiple sclerosis.

    PubMed

    Cohen, Mikhal E; Fainstein, Nina; Lavon, Iris; Ben-Hur, Tamir

    2014-09-01

    Multiple sclerosis (MS) is a multifocal disease, and precursor cells need to migrate into the multiple lesions in order to exert their therapeutic effects. Therefore, cell migration is a crucial element in regenerative processes in MS, dictating the route of delivery, when cell transplantation is considered. We have previously shown that inflammation triggers migration of multi-potential neural precursor cells (NPCs) into the white matter of experimental autoimmune encephalomyelitis (EAE) rodents, a widely used model of MS. Here we investigated the molecular basis of this attraction. NPCs were grown from E13 embryonic mouse brains and transplanted into the lateral cerebral ventricles of EAE mice. Transplanted NPC migration was directed by three tissue-derived chemokines. Stromal cell-derived factor-1α, monocyte chemo-attractant protein-1 and hepatocyte growth factor were expressed in the EAE brain and specifically in microglia and astrocytes. Their cognate receptors, CXCR4, CCR2 or c-Met were constitutively expressed on NPCs. Selective blockage of CXCR4, CCR2 or c-Met partially inhibited NPC migration in EAE brains. Blocking all three receptors had an additive effect and resulted in profound inhibition of NPC migration, as compared to extensive migration of control NPCs. The inflammation-triggered NPC migration into white matter tracts was dependent on a motile NPC phenotype. Specifically, depriving NPCs from epidermal growth factor (EGF) prevented the induction of glial commitment and a motile phenotype (as indicated by an in vitro motility assay), hampering their response to neuroinflammation. In conclusion, signaling via three chemokine systems accounts for most of the inflammation-induced, tissue-derived attraction of transplanted NPCs into white matter tracts during EAE. PMID:25086214

  17. Human Embryonic Stem Cell-Derived Neural Precursors Develop Into Neurons and Integrate Into the Host Brain

    PubMed Central

    Guillaume, Daniel J.; Johnson, M. Austin; Li, Xue-Jun; Zhang, Su-Chun

    2009-01-01

    Whether and how in-vitro-produced human neural precursors mature and integrate into the brain are crucial to the utility of human embryonic stem (hES) cells in treating neurological disorders. After transplantation into the ventricles of neonatal immune-deficient mice, hES-cell-derived neural precursors stopped expressing the cell division marker Ki67, except in neurogenic areas, and differentiated into neurons and then glia in a temporal course intrinsic to that of human cells regardless of location. The human cells located in the gray matter became neurons in the olfactory bulb and striatum, whereas those in the white matter produced exclusively glia. Importantly, the grafted human cells formed synapses. Thus, the in-vitro-produced human neural precursors follow their intrinsic temporal program to produce neurons and glia and, in response to environmental signals, generate cells appropriate to their target regions and integrate into the brain. PMID:16941479

  18. Epidermal growth factor precursor in mouse lactating mammary gland alveolar cells

    SciTech Connect

    Brown, C.F.; Teng, C.T.; Pentecost, B.T.; DiAugustine, R.P. )

    1989-07-01

    Previous studies have demonstrated that high levels of epidermal growth factor (EGF) occur in human and rodent milk and that oral administration of this polypeptide stimulates rodent gastrointestinal development. It is not known whether EGF in milk originates from cells of the lactating mammary gland or is sequestered from an extramammary source. In the present study, prepro-EGF mRNA (approximately 4.7 kilobases) was detected in the CD-1 mouse mammary gland throughout the period of lactation; by comparison, negligible levels of this EGF transcript were found in the gland during pregnancy. Low levels of EGF immunoreactivity (4-5 ng/g wet wt tissue) were extracted from lactating (day 18) mammary glands with dilute acetic acid. Immunolocalization was evident with antisera to either EGF or two other regions of the EGF precursor in essentially all alveolar cells of the lactating gland. The most prominent staining with antiserum to EGF was observed along the luminal borders of cells; this pattern of cellular staining required proteolytic pretreatment of tissue sections. Western blot analyses of cell membranes isolated from the day 16 lactating mammary gland revealed an EGF-immunoreactive band at about 145K, which was equivalent in size to the EGF precursor found in mouse kidney cell membranes. Despite these findings, labeling of lactating mammary gland mince with L-(35S)methionine and cysteine for up to 4 h did not reveal any specific bands in immunoprecipitates. These cumulative findings suggest that the precursor form of EGF occurs in alveolar cells of lactating mammary gland and that this protein is translocated to the cell membrane.

  19. Animal models for studying neural crest development: is the mouse different?

    PubMed

    Barriga, Elias H; Trainor, Paul A; Bronner, Marianne; Mayor, Roberto

    2015-05-01

    The neural crest is a uniquely vertebrate cell type and has been well studied in a number of model systems. Zebrafish, Xenopus and chick embryos largely show consistent requirements for specific genes in early steps of neural crest development. By contrast, knockouts of homologous genes in the mouse often do not exhibit comparable early neural crest phenotypes. In this Spotlight article, we discuss these species-specific differences, suggest possible explanations for the divergent phenotypes in mouse and urge the community to consider these issues and the need for further research in complementary systems. PMID:25922521

  20. Roles of neural precursor cell expressed, developmentally downregulated 9 in tumor-associated cellular processes (Review).

    PubMed

    Zhang, Sisen; Wu, Lihua

    2015-11-01

    Neural precursor cell expressed, developmentally downregulated 9 (NEDD9), a gene exclusively expressed in the brain during embryonic stages but not in brains of adult mice, is an important cytoskeletal protein and regarded as a 'router/hub' in cellular signal transduction processes connecting external stimulation signals with downstream target proteins that can directly promote tumor metastasis. Numerous studies showed that NEDD9 has an essential role in cell proliferation, apoptosis, adhesion, migration and invasion. The roles of NEDD9, including the underlying mechanisms of its regulation of cell migration, its distinctive functions in various tumor stages and its association with other diseases, are required to be elucidated at large. Future studies of NEDD9 may provide a more profound understanding of the development of tumor invasiveness and NEDD9 may serve as a potential novel target for tumor therapy. The present review examined the significant roles of NEDD9 in the abovementioned processes. PMID:26324022

  1. Standardized Generation and Differentiation of Neural Precursor Cells from Human Pluripotent Stem Cells

    PubMed Central

    Kozhich, O; Hamilton, RS; Mallon, BS

    2012-01-01

    Precise, robust and scalable directed differentiation of pluripotent stem cells is an important goal with respect to disease modeling or future therapies. Using the AggreWell™400 system we have standardized the differentiation of human embryonic and induced pluripotent stem cells to a neuronal fate using defined conditions. This allows reproducibility in replicate experiments and facilitates the direct comparison of cell lines. Since the starting point for EB formation is a single cell suspension, this protocol is suitable for standard and novel methods of pluripotent stem cell culture. Moreover, an intermediate population of neural precursor cells, which are routinely >95% NCAMpos and Tra-1–60neg by FACS analysis, may be expanded and frozen prior to differentiation allowing a convenient starting point for downstream experiments. PMID:22388559

  2. The capsaicin receptor TRPV1 as a novel modulator of neural precursor cell proliferation.

    PubMed

    Stock, Kristin; Garthe, Alexander; de Almeida Sassi, Felipe; Glass, Rainer; Wolf, Susanne A; Kettenmann, Helmut

    2014-12-01

    The capsaicin receptor (TRPV1, transient receptor potential vanilloid type 1) was first discovered in the peripheral nervous system as a detector of noxious chemical and thermal stimuli including the irritant chili pepper. Recently, there has been increasing evidence of TRPV1 expression in the central nervous system. Here, we show that TRPV1 is expressed in neural precursor cells (NPCs) during postnatal development, but not in the adult. However, expression of TRPV1 is induced in the adult in paradigms linked to an increase in neurogenesis, such as spatial learning in the Morris water maze or voluntary exercise. Loss of TRPV1 expression in knockout mice leads to an increase in NPC proliferation. Functional TRPV1 expression has been confirmed in cultured NPCs. Our results indicate that TRPV1 expression influences both postnatal and activity-induced neurogenesis in adulthood. PMID:25092424

  3. Learning-induced synaptic potentiation in implanted neural precursor cell-derived neurons

    PubMed Central

    Park, Kyungjoon; Heo, Hwon; Han, Ma Eum; Choi, Kyuhyun; Yi, Jee Hyun; Kang, Shin Jung; Kwon, Yunhee Kim; Shin, Ki Soon

    2015-01-01

    Neuronal loss caused by neurodegenerative diseases, traumatic brain injury and stroke results in cognitive dysfunctioning. Implantation of neural stem/precursor cells (NPCs) can improve the brain function by replacing lost neurons. Proper synaptic integration following neuronal differentiation of implanted cells is believed to be a prerequisite for the functional recovery. In the present study, we characterized the functional properties of immortalized neural progenitor HiB5 cells implanted into the rat hippocampus with chemically induced lesion. The implanted HiB5 cells migrated toward CA1 pyramidal layer and differentiated into vGluT1-positive glutamatergic neurons with morphological and electrophysiological properties of endogenous CA1 pyramidal cells. Functional synaptic integration of HiB5 cell-derived neurons was also evidenced by immunohistochemical and electrophysiological data. Lesion-caused memory deficit was significantly recovered after the implantation when assessed by inhibitory avoidance (IA) learning. Remarkably, IA learning preferentially produced long-term potentiation (LTP) at the synapses onto HiB5 cell-derived neurons, which occluded paring protocol-induced LTP ex vivo. We conclude that the implanted HiB5 cell-derived neurons actively participate in learning process through LTP formation, thereby counteracting lesion-mediated memory impairment. PMID:26634434

  4. GDNF facilitates differentiation of the adult dentate gyrus-derived neural precursor cells into astrocytes via STAT3

    SciTech Connect

    Boku, Shuken; Nakagawa, Shin; Takamura, Naoki; Kato, Akiko; Takebayashi, Minoru; Hisaoka-Nakashima, Kazue; Omiya, Yuki; Inoue, Takeshi; Kusumi, Ichiro

    2013-05-17

    Highlights: •GDNF has no effect on ADP proliferation and apoptosis. •GDNF increases ADP differentiation into astrocyte. •A specific inhibitor of STAT3 decreases the astrogliogenic effect of GDNF. •STAT3 knockdown by lentiviral shRNA vector also decreases the astrogliogenic effect of GDNF. •GDNF increases the phosphorylation of STAT3. -- Abstract: While the pro-neurogenic actions of antidepressants in the adult hippocampal dentate gyrus (DG) are thought to be one of the mechanisms through which antidepressants exert their therapeutic actions, antidepressants do not increase proliferation of neural precursor cells derived from the adult DG. Because previous studies showed that antidepressants increase the expression and secretion of glial cell line-derived neurotrophic factor (GDNF) in C6 glioma cells derived from rat astrocytes and GDNF increases neurogenesis in adult DG in vivo, we investigated the effects of GDNF on the proliferation, differentiation and apoptosis of cultured neural precursor cells derived from the adult DG. Data showed that GDNF facilitated the differentiation of neural precursor cells into astrocytes but had no effect on their proliferation or apoptosis. Moreover, GDNF increased the phosphorylation of STAT3, and both a specific inhibitor of STAT3 and lentiviral shRNA for STAT3 decreased their differentiation into astrocytes. Taken together, our findings suggest that GDNF facilitates astrogliogenesis from neural precursor cells in adult DG through activating STAT3 and that this action might indirectly affect neurogenesis.

  5. Precursors to morality in development as a complex interplay between neural, socioenvironmental, and behavioral facets.

    PubMed

    Cowell, Jason M; Decety, Jean

    2015-10-13

    The nature and underpinnings of infants' seemingly complex, third-party, social evaluations remain highly contentious. Theoretical perspectives oscillate between rich and lean interpretations of the same expressed preferences. Although some argue that infants and toddlers possess a "moral sense" based on core knowledge of the social world, others suggest that social evaluations are hierarchical in nature and the product of an integration of rudimentary general processes such as attention allocation and approach and avoidance. Moreover, these biologically prepared minds interact in social environments that include significant variation, which are likely to impact early social evaluations and behavior. The present study examined the neural underpinnings of and precursors to moral sensitivity in infants and toddlers (n = 73, ages 12-24 mo) through a series of interwoven measures, combining multiple levels of analysis including electrophysiological, eye-tracking, behavioral, and socioenvironmental. Continuous EEG and time-locked event-related potentials (ERPs) and gaze fixation were recorded while children watched characters engaging in prosocial and antisocial actions in two different tasks. All children demonstrated a neural differentiation in both spectral EEG power density modulations and time-locked ERPs when perceiving prosocial or antisocial agents. Time-locked neural differences predicted children's preference for prosocial characters and were influenced by parental values regarding justice and fairness. Overall, this investigation casts light on the fundamental nature of moral cognition, including its underpinnings in general processes such as attention and approach-withdrawal, providing plausible mechanisms of early change and a foundation for forward movement in the field of developmental social neuroscience. PMID:26324885

  6. Precursors to morality in development as a complex interplay between neural, socioenvironmental, and behavioral facets

    PubMed Central

    Cowell, Jason M.; Decety, Jean

    2015-01-01

    The nature and underpinnings of infants’ seemingly complex, third-party, social evaluations remain highly contentious. Theoretical perspectives oscillate between rich and lean interpretations of the same expressed preferences. Although some argue that infants and toddlers possess a “moral sense” based on core knowledge of the social world, others suggest that social evaluations are hierarchical in nature and the product of an integration of rudimentary general processes such as attention allocation and approach and avoidance. Moreover, these biologically prepared minds interact in social environments that include significant variation, which are likely to impact early social evaluations and behavior. The present study examined the neural underpinnings of and precursors to moral sensitivity in infants and toddlers (n = 73, ages 12–24 mo) through a series of interwoven measures, combining multiple levels of analysis including electrophysiological, eye-tracking, behavioral, and socioenvironmental. Continuous EEG and time-locked event-related potentials (ERPs) and gaze fixation were recorded while children watched characters engaging in prosocial and antisocial actions in two different tasks. All children demonstrated a neural differentiation in both spectral EEG power density modulations and time-locked ERPs when perceiving prosocial or antisocial agents. Time-locked neural differences predicted children’s preference for prosocial characters and were influenced by parental values regarding justice and fairness. Overall, this investigation casts light on the fundamental nature of moral cognition, including its underpinnings in general processes such as attention and approach–withdrawal, providing plausible mechanisms of early change and a foundation for forward movement in the field of developmental social neuroscience. PMID:26324885

  7. Activated mast cells release biological activities able to support eosinophil production from mouse hemopoietic precursors.

    PubMed

    Oskéritzian, C; Milon, G; Braquet, P; Mencia-Huerta, J M; David, B

    1996-02-01

    Mouse bone marrow cells cultured for 6 days in the presence of recombinant murine IL-3 and granulocyte-macrophage colony-stimulating factor (GM-CSF) were used as a source of precursors responsive to eosinopoietins. They were further cultured for 7 days in the presence of either a combination of recombinant cytokines or supernatants of bone marrow-derived mast cells (BMMC) activated with either immunological or nonimmunological stimuli. Cytosmears of collected cells were analyzed for eosinophil contents and allowed to demonstrate that supernatants of passively sensitized BMMC support both total cell proliferation and eosinophil production, after various periods of incubation with monoclonal rat anti-mouse IgE antibodies (the 6HD5 mAbs). In contrast, a stimulation with 100 ng/ml dinitrophenylated bovine serum albumin (DNP-BSA) did not generate supernatants displaying such bioactivities. Low doses of methyl ester of L (but not D)-leucine or of the calcium ionophore A23187 also allowed the release of eosinopoietic bioactivities. In addition, immunoreactive IL-5, GM-CSF, and IL-3 were quantified in the BMMC supernatants. These results demonstrate that activated BMMC are able to effect eosinophil production. PMID:8603429

  8. Microglia-derived TNFα induces apoptosis in neural precursor cells via transcriptional activation of the Bcl-2 family member Puma

    PubMed Central

    Guadagno, J; Xu, X; Karajgikar, M; Brown, A; Cregan, S P

    2013-01-01

    Neuroinflammation is a common feature of acute neurological conditions such as stroke and spinal cord injury, as well as neurodegenerative conditions such as Parkinson's disease, Alzheimer's disease, and amyotrophic lateral sclerosis. Previous studies have demonstrated that acute neuroinflammation can adversely affect the survival of neural precursor cells (NPCs) and thereby limit the capacity for regeneration and repair. However, the mechanisms by which neuroinflammatory processes induce NPC death remain unclear. Microglia are key mediators of neuroinflammation and when activated to induce a pro-inflammatory state produce a number of factors that could affect NPC survival. Importantly, in the present study we demonstrate that tumor necrosis factor α (TNFα) produced by lipopolysaccharide-activated microglia is necessary and sufficient to trigger apoptosis in mouse NPCs in vitro. Furthermore, we demonstrate that microglia-derived TNFα induces NPC apoptosis via a mitochondrial pathway regulated by the Bcl-2 family protein Bax. BH3-only proteins are known to play a key role in regulating Bax activation and we demonstrate that microglia-derived TNFα induces the expression of the BH3-only family member Puma in NPCs via an NF-κB-dependent mechanism. Specifically, we show that NF-κB is activated in NPCs treated with conditioned media from activated microglia and that Puma induction and NPC apoptosis is blocked by the NF-κB inhibitor BAY-117082. Importantly, we have determined that NPC apoptosis induced by activated microglia-derived TNFα is attenuated in Puma-deficient NPCs, indicating that Puma induction is required for NPC death. Consistent with this, we demonstrate that Puma-deficient NPCs exhibit an ∼13-fold increase in survival as compared with wild-type NPCs following transplantation into the inflammatory environment of the injured spinal cord in vivo. In summary, we have identified a key signaling pathway that regulates neuroinflammation induced apoptosis

  9. Microglia-derived TNFα induces apoptosis in neural precursor cells via transcriptional activation of the Bcl-2 family member Puma.

    PubMed

    Guadagno, J; Xu, X; Karajgikar, M; Brown, A; Cregan, S P

    2013-01-01

    Neuroinflammation is a common feature of acute neurological conditions such as stroke and spinal cord injury, as well as neurodegenerative conditions such as Parkinson's disease, Alzheimer's disease, and amyotrophic lateral sclerosis. Previous studies have demonstrated that acute neuroinflammation can adversely affect the survival of neural precursor cells (NPCs) and thereby limit the capacity for regeneration and repair. However, the mechanisms by which neuroinflammatory processes induce NPC death remain unclear. Microglia are key mediators of neuroinflammation and when activated to induce a pro-inflammatory state produce a number of factors that could affect NPC survival. Importantly, in the present study we demonstrate that tumor necrosis factor α (TNFα) produced by lipopolysaccharide-activated microglia is necessary and sufficient to trigger apoptosis in mouse NPCs in vitro. Furthermore, we demonstrate that microglia-derived TNFα induces NPC apoptosis via a mitochondrial pathway regulated by the Bcl-2 family protein Bax. BH3-only proteins are known to play a key role in regulating Bax activation and we demonstrate that microglia-derived TNFα induces the expression of the BH3-only family member Puma in NPCs via an NF-κB-dependent mechanism. Specifically, we show that NF-κB is activated in NPCs treated with conditioned media from activated microglia and that Puma induction and NPC apoptosis is blocked by the NF-κB inhibitor BAY-117082. Importantly, we have determined that NPC apoptosis induced by activated microglia-derived TNFα is attenuated in Puma-deficient NPCs, indicating that Puma induction is required for NPC death. Consistent with this, we demonstrate that Puma-deficient NPCs exhibit an ∼13-fold increase in survival as compared with wild-type NPCs following transplantation into the inflammatory environment of the injured spinal cord in vivo. In summary, we have identified a key signaling pathway that regulates neuroinflammation induced apoptosis

  10. Tripartite containing motif 32 modulates proliferation of human neural precursor cells in HIV-1 neurodegeneration.

    PubMed

    Fatima, M; Kumari, R; Schwamborn, J C; Mahadevan, A; Shankar, S K; Raja, R; Seth, P

    2016-05-01

    In addition to glial cells, HIV-1 infection occurs in multipotent human neural precursor cells (hNPCs) and induces quiescence in NPCs. HIV-1 infection of the brain alters hNPC stemness, leading to perturbed endogenous neurorestoration of the CNS following brain damage by HIV-1, compounding the severity of dementia in adult neuroAIDS cases. In pediatric neuroAIDS cases, HIV-1 infection of neural stem cell can lead to delayed developmental milestones and impaired cognition. Using primary cultures of human fetal brain-derived hNPCs, we gained novel insights into the role of a neural stem cell determinant, tripartite containing motif 32 (TRIM32), in HIV-1 Tat-induced quiescence of NPCs. Acute HIV-1 Tat treatment of hNPCs resulted in proliferation arrest but did not induce differentiation. Cellular localization and levels of TRIM32 are critical regulators of stemness of NPCs. HIV-1 Tat exposure increased nuclear localization and levels of TRIM32 in hNPCs. The in vitro findings were validated by studying TRIM32 localization and levels in frontal cortex of HIV-1-seropositive adult patients collected at post mortem as well as by infection of hNPCs by HIV-1. We observed increased percentage of cells with nuclear localization of TRIM32 in the subventricular zone (SVZ) as compared with age-matched controls. Our quest for probing into the mechanisms revealed that TRIM32 is targeted by miR-155 as downregulation of miR-155 by HIV-1 Tat resulted in upregulation of TRIM32 levels. Furthermore, miR-155 or siRNA against TRIM32 rescued HIV-1 Tat-induced quiescence in NPCs. Our findings suggest a novel molecular cascade involving miR-155 and TRIM32 leading to HIV-1 Tat-induced attenuated proliferation of hNPCs. The study also uncovered an unidentified role for miR-155 in modulating human neural stem cell proliferation, helping in better understanding of hNPCs and diseased brain. PMID:26586575

  11. Tripartite containing motif 32 modulates proliferation of human neural precursor cells in HIV-1 neurodegeneration

    PubMed Central

    Fatima, M; Kumari, R; Schwamborn, J C; Mahadevan, A; Shankar, S K; Raja, R; Seth, P

    2016-01-01

    In addition to glial cells, HIV-1 infection occurs in multipotent human neural precursor cells (hNPCs) and induces quiescence in NPCs. HIV-1 infection of the brain alters hNPC stemness, leading to perturbed endogenous neurorestoration of the CNS following brain damage by HIV-1, compounding the severity of dementia in adult neuroAIDS cases. In pediatric neuroAIDS cases, HIV-1 infection of neural stem cell can lead to delayed developmental milestones and impaired cognition. Using primary cultures of human fetal brain-derived hNPCs, we gained novel insights into the role of a neural stem cell determinant, tripartite containing motif 32 (TRIM32), in HIV-1 Tat-induced quiescence of NPCs. Acute HIV-1 Tat treatment of hNPCs resulted in proliferation arrest but did not induce differentiation. Cellular localization and levels of TRIM32 are critical regulators of stemness of NPCs. HIV-1 Tat exposure increased nuclear localization and levels of TRIM32 in hNPCs. The in vitro findings were validated by studying TRIM32 localization and levels in frontal cortex of HIV-1-seropositive adult patients collected at post mortem as well as by infection of hNPCs by HIV-1. We observed increased percentage of cells with nuclear localization of TRIM32 in the subventricular zone (SVZ) as compared with age-matched controls. Our quest for probing into the mechanisms revealed that TRIM32 is targeted by miR-155 as downregulation of miR-155 by HIV-1 Tat resulted in upregulation of TRIM32 levels. Furthermore, miR-155 or siRNA against TRIM32 rescued HIV-1 Tat-induced quiescence in NPCs. Our findings suggest a novel molecular cascade involving miR-155 and TRIM32 leading to HIV-1 Tat-induced attenuated proliferation of hNPCs. The study also uncovered an unidentified role for miR-155 in modulating human neural stem cell proliferation, helping in better understanding of hNPCs and diseased brain. PMID:26586575

  12. Molecular characterization of six intermediate proteins in the processing of mouse protamine P2 precursor.

    PubMed

    Chauvière, M; Martinage, A; Debarle, M; Sautière, P; Chevaillier, P

    1992-03-01

    In mouse spermatozoa, DNA is compacted by two protamines mP1 and mP2. Protamine mP2 (63 residues) is synthesized in spermatid nuclei as a precursor pmP2 (106 residues) which is subsequently processed at the end of spermiogenesis [Yelick, P.C., Balhorn, R., Johnson, P.A., Corzett, M., Mazrimas, J.A., Kleene, K.C. & Hecht, N.B. (1987) Mol. Cell. Biol. 7, 2173-2179]. Six proteins, three of which were described earlier [Chauvière, M., Martinage, A., Debarle, M., Alimi, E., Sautière, P. & Chevaillier, Ph. (1991) C.R. Acad. Sci. 313, 107-112], have molecular and electrophoretic properties similar to those of pmP2. They were isolated from purified testis nuclei and characterized by amino acid composition, N-terminal sequence and peptide mapping. From the amino acid compositions, it appears that all six proteins are rich in arginine, cysteine and histidine and are closely related to pmP2 and mP2. The N-terminal sequence of each protein overlaps a distinct region of the N-terminal part of pmP2. The C-terminal part of protamine mP2 starting at arginine 15 is common to all proteins as assessed by amino acid compositions and peptide maps. All these structural data demonstrate that the six isolated proteins are products of pmP2 precursor processing. The six intermediate proteins pmP2/5, pmP2/11, pmP2/16, pmP2/20, pmP2/26 and pmP2/32 which contain 102, 96, 91, 87, 81 and 75 residues, respectively, are generated from the pmP2 precursor after N-terminal excision of 4, 10, 15, 19, 25 and 31 residues, respectively. The C-terminal sequence of protamine mP2 is strictly identical to that of its precursor; therefore, no maturation occurs in this part of the molecule. At the present time, the proteolytic pathway involved in the amino-terminal processing leading to the mature form of the protamine mP2 (63 residues) has not been elucidated. However, the different representation of six intermediates in the testis suggests that some stages of processing are faster than others or that some

  13. Skeletal myogenic potential of human and mouse neural stem cells.

    PubMed

    Galli, R; Borello, U; Gritti, A; Minasi, M G; Bjornson, C; Coletta, M; Mora, M; De Angelis, M G; Fiocco, R; Cossu, G; Vescovi, A L

    2000-10-01

    Distinct cell lineages established early in development are usually maintained throughout adulthood. Thus, adult stem cells have been thought to generate differentiated cells specific to the tissue in which they reside. This view has been challenged; for example, neural stem cells can generate cells that normally originate from a different germ layer. Here we show that acutely isolated and clonally derived neural stem cells from mice and humans could produce skeletal myotubes in vitro and in vivo, the latter following transplantation into adult animals. Myogenic conversion in vitro required direct exposure to myoblasts, and was blocked if neural cells were clustered. Thus, a community effect between neural cells may override such myogenic induction. We conclude that neural stem cells, which generate neurons, glia and blood cells, can also produce skeletal muscle cells, and can undergo various patterns of differentiation depending on exposure to appropriate epigenetic signals in mature tissues. PMID:11017170

  14. A reduction in Npas4 expression results in delayed neural differentiation of mouse embryonic stem cells

    PubMed Central

    2014-01-01

    Introduction Npas4 is a calcium-dependent transcription factor expressed within neurons of the brain where it regulates the expression of several genes that are important for neuronal survival and synaptic plasticity. It is known that in the adult brain Npas4 plays an important role in several key aspects of neurobiology including inhibitory synapse formation, neuroprotection and memory, yet very little is known about the role of Npas4 during neurodevelopment. The aim of this study was to examine the expression and function of Npas4 during nervous system development by using a combination of in vivo experiments in the developing mouse embryo and neural differentiation of embryonic stem cells (ESCs) as an in vitro model of the early stages of embryogenesis. Methods Two different neural differentiation paradigms were used to investigate Npas4 expression during neurodevelopment in vitro; adherent monolayer differentiation of mouse ESCs in N2B27 medium and Noggin-induced differentiation of human ESCs. This work was complemented by direct analysis of Npas4 expression in the mouse embryo. The function of Npas4 in the context of neurodevelopment was investigated using loss-of-function experiments in vitro. We created several mouse ESC lines in which Npas4 expression was reduced during neural differentiation through RNA interference and we then analyzed the ability of these Npas4 knockdown mouse ESCs lines to undergo neural differentiation. Results We found that while Npas4 is not expressed in undifferentiated ESCs, it becomes transiently up-regulated during neural differentiation of both mouse and human ESCs at a stage of differentiation that is characterized by proliferation of neural progenitor cells. This was corroborated by analysis of Npas4 expression in the mouse embryo where the Npas4 transcript was detected specifically in the developing forebrain beginning at embryonic day 9.5. Finally, knockdown of Npas4 expression in mouse ESCs undergoing neural differentiation

  15. Neural precursors isolated from the developing cat brain show retinal integration following transplantation to the retina of the dystrophic cat.

    PubMed

    Klassen, Henry; Schwartz, Philip H; Ziaeian, Boback; Nethercott, Hubert; Young, Michael J; Bragadottir, Ragnheidur; Tullis, Gregory E; Warfvinge, Karin; Narfstrom, Kristina

    2007-01-01

    The cat has served as an important nonrodent research model for neurophysiology and retinal degenerative disease processes, yet very little is known about feline neural precursor cells. To culture these cells and evaluate marker expression, brains were dissected from 45-day-old fetuses, enzymatically dissociated, and grown in the presence of EGF, bFGF and PDGF. Expanded cells widely expressed nestin, Sox2, Ki-67, fusin (CXCR4) and vimentin, while subpopulations expressed A2B5, GFAP, or beta-III tubulin. Precursors prelabeled with BrdU and/or transduced with a recombinant lentivirus that expresses GFP were transplanted subretinally in five dystrophic Abyssinian cats. Two to 4 weeks following surgery, histology showed survival of grafted cells in three of the animals. Labeled cells were found in the neuroretina and RPE layer, as well as in the vitreous and the vicinity of Bruch's membrane. There was no evidence of an immunologic response in any of the eyes. Neural precursor cells can therefore be cultured from the developing cat brain and survive as allografts for up to 4 weeks without immune suppression. The feasibility of deriving and transplanting feline neural precursor cells, combined with the availability of the dystrophic Abyssinian cat, provide a new feline model system for the study of retinal repair. PMID:17565557

  16. Differentiation of Retinal Ganglion Cells and Photoreceptor Precursors from Mouse Induced Pluripotent Stem Cells Carrying an Atoh7/Math5 Lineage Reporter

    PubMed Central

    Hashimoto, Takao; Tien, Amy H.; Chen, Andrew; Ge, Jian; Yang, Xian-Jie

    2014-01-01

    The neural retina is a critical component of the visual system, which provides the majority of sensory input in humans. Various retinal degenerative diseases can result in the permanent loss of retinal neurons, especially the light-sensing photoreceptors and the centrally projecting retinal ganglion cells (RGCs). The replenishment of lost RGCs and the repair of optic nerve damage are particularly challenging, as both RGC specification and their subsequent axonal growth and projection involve complex and precise regulation. To explore the developmental potential of pluripotent stem cell-derived neural progenitors, we have established mouse iPS cells that allow cell lineage tracing of progenitors that have expressed Atoh7/Math5, a bHLH transcription factor required for RGC production. These Atoh7 lineage reporter iPS cells encode Cre to replace one copy of the endogenous Atoh7 gene and a Cre-dependent YFP reporter in the ROSA locus. In addition, they express pluripotent markers and are capable of generating teratomas in vivo. Under anterior neural induction and neurogenic conditions in vitro, the Atoh7-Cre/ROSA-YFP iPS cells differentiate into neurons that co-express various RGC markers and YFP, indicating that these neurons are derived from Atoh7-expressing progenitors. Consistent with previous in vivo cell lineage studies, the Atoh7-Cre/ROSA-YFP iPS cells also give rise to a subset of Crx-positive photoreceptor precursors. Furthermore, inhibition of Notch signaling in the iPSC cultures results in a significant increase of YFP-positive RGCs and photoreceptor precursors. Together, these results show that Atoh7-Cre/ROSA-YFP iPS cells can be used to monitor the development and survival of RGCs and photoreceptors from pluripotent stem cells. PMID:25401462

  17. Differentiation of retinal ganglion cells and photoreceptor precursors from mouse induced pluripotent stem cells carrying an Atoh7/Math5 lineage reporter.

    PubMed

    Xie, Bin-Bin; Zhang, Xiang-Mei; Hashimoto, Takao; Tien, Amy H; Chen, Andrew; Ge, Jian; Yang, Xian-Jie

    2014-01-01

    The neural retina is a critical component of the visual system, which provides the majority of sensory input in humans. Various retinal degenerative diseases can result in the permanent loss of retinal neurons, especially the light-sensing photoreceptors and the centrally projecting retinal ganglion cells (RGCs). The replenishment of lost RGCs and the repair of optic nerve damage are particularly challenging, as both RGC specification and their subsequent axonal growth and projection involve complex and precise regulation. To explore the developmental potential of pluripotent stem cell-derived neural progenitors, we have established mouse iPS cells that allow cell lineage tracing of progenitors that have expressed Atoh7/Math5, a bHLH transcription factor required for RGC production. These Atoh7 lineage reporter iPS cells encode Cre to replace one copy of the endogenous Atoh7 gene and a Cre-dependent YFP reporter in the ROSA locus. In addition, they express pluripotent markers and are capable of generating teratomas in vivo. Under anterior neural induction and neurogenic conditions in vitro, the Atoh7-Cre/ROSA-YFP iPS cells differentiate into neurons that co-express various RGC markers and YFP, indicating that these neurons are derived from Atoh7-expressing progenitors. Consistent with previous in vivo cell lineage studies, the Atoh7-Cre/ROSA-YFP iPS cells also give rise to a subset of Crx-positive photoreceptor precursors. Furthermore, inhibition of Notch signaling in the iPSC cultures results in a significant increase of YFP-positive RGCs and photoreceptor precursors. Together, these results show that Atoh7-Cre/ROSA-YFP iPS cells can be used to monitor the development and survival of RGCs and photoreceptors from pluripotent stem cells. PMID:25401462

  18. LIF-dependent primitive neural stem cells derived from mouse ES cells represent a reversible stage of neural commitment.

    PubMed

    Tsang, Wan-Hong; Wang, Bin; Wong, Wing Ki; Shi, Shuo; Chen, Xiao; He, Xiangjun; Gu, Shen; Hu, Jiabiao; Wang, Chengdong; Liu, Pi-Chu; Lu, Gang; Chen, Xiongfong; Zhao, Hui; Poon, Wai-Sang; Chan, Wai-Yee; Feng, Bo

    2013-11-01

    Primitive neural stem cells (NSCs) define an early stage of neural induction, thus provide a model to understand the mechanism that controls initial neural commitment. In this study, we investigated primitive NSCs derived from mouse embryonic stem cells (ESCs). By genome-wide transcriptional profiling, we revealed their unique signature and depicted the molecular changes underlying critical cell fate transitions during early neural induction at a global level. Together with qRT-PCR analysis, our data illustrated that primitive NSCs retained expression of key pluripotency genes Oct4 and Nanog, while exhibiting repression of other pluripotency-related genes Zscan4, Foxp1 and Dusp9 and up-regulation of neural markers Sox1 and Hes1. The early differentiation feature in primitive NSCs was also supported by their intermediate characters on cell cycle profiles. Moreover, re-plating primitive NSCs back to ESC culture condition could reverse them back to ESC stage, as shown by reversible regulation of marker genes, cell cycle profile changes and enhanced embryoid body formation. In addition, our microarray analysis also identified genes differentially expressed in primitive NSCs, and loss-of-function analysis demonstrated that Hes1 and Ccdc141 play important function at this stage, opening up an opportunity to further understand the regulation of early neural commitment. PMID:23973799

  19. Biochemical and functional characterization of transiently expressed in neural precursor (TENP) protein in emu egg white.

    PubMed

    Maehashi, Kenji; Ueda, Megumi; Matano, Mami; Takeuchi, Junko; Uchino, Masataka; Kashiwagi, Yutaka; Watanabe, Toshihiro

    2014-06-01

    A protein transiently expressed in the neural precursors of developing tissues (TENP) was found to be present in emu (Dromaius novaehollandiae) egg white as one of the major proteins. Nucleotide analysis of its encoding cDNA revealed a sequence of 452 amino acids including a 19 amino acid peptide signal. Phylogenetic analysis determined that emu TENP was clustered within the bactericidal/permeability-increasing protein (BPI) superfamily together with other avian TENPs. RT-PCR analysis revealed that the emu TENP gene was highly expressed in the magnum of the oviduct, indicating that TENP is a major egg white component. Emu TENP was purified by anion exchange chromatography and ammonium sulfate fractionation. Unlike BPI, emu TENP exhibited antibacterial activity against Gram-positive bacteria, including Micrococcus luteus and Bacillus subtilis, but not against Gram-negative bacteria such as Escherichia coli and Salmonella Typhimurium. The results suggest that emu TENP is a potent novel antibacterial protein with a spectrum distinct from that of BPI. PMID:24820544

  20. Synergic interaction between amyloid precursor protein and neural cell adhesion molecule promotes neurite outgrowth

    PubMed Central

    Chen, Keping; Lu, Huixia; Gao, Tianli; Xue, Xiulei; Wang, Chunling; Miao, Fengqin

    2016-01-01

    Alzheimer's disease (AD) is one of the most common neurodegenerative diseases worldwide. The main features of AD are the pathological changes of density and distribution of intracellular neurofibrillary tangles (NFT) and extracellular amyloid plaques. The processing of amyloid beta precursor protein (APP) to β-amyloid peptide (Aβ) is one of the critical events in the pathogenesis of AD. In this study, we evaluated the role of the interaction of neural cell adhesion molecule (NCAM) and APP in neurite outgrowth using two different experimental systems: PC12E2 cells and hippocampal neurons that were isolated from wild type, APP knock-in and APP knock-out mice. PC12E2 cells or hippocampal neurons were co-cultured with NCAM-negative or NCAM-positive fibroblasts L929 cells. We found that APP promoted neurite outgrowth of PC12E2 cells and hippocampal neurons in either the presence or absence of NCAM. Secreted APP can rescue the neurite outgrowth in hippocampal neurons from APP knock-out mice. The interaction of APP and NCAM had synergic effect in promoting neurite outgrowth in both PC12E2 cells and hippocampal neurons. Our results suggested that the interaction of APP with NCAM played an important role in AD development and therefore could be a potential therapeutic target for AD treatment. PMID:26883101

  1. Human neural precursor cells promote neurologic recovery in a viral model of multiple sclerosis.

    PubMed

    Chen, Lu; Coleman, Ronald; Leang, Ronika; Tran, Ha; Kopf, Alexandra; Walsh, Craig M; Sears-Kraxberger, Ilse; Steward, Oswald; Macklin, Wendy B; Loring, Jeanne F; Lane, Thomas E

    2014-06-01

    Using a viral model of the demyelinating disease multiple sclerosis (MS), we show that intraspinal transplantation of human embryonic stem cell-derived neural precursor cells (hNPCs) results in sustained clinical recovery, although hNPCs were not detectable beyond day 8 posttransplantation. Improved motor skills were associated with a reduction in neuroinflammation, decreased demyelination, and enhanced remyelination. Evidence indicates that the reduced neuroinflammation is correlated with an increased number of CD4(+)CD25(+)FOXP3(+) regulatory T cells (Tregs) within the spinal cords. Coculture of hNPCs with activated T cells resulted in reduced T cell proliferation and increased Treg numbers. The hNPCs acted, in part, through secretion of TGF-β1 and TGF-β2. These findings indicate that the transient presence of hNPCs transplanted in an animal model of MS has powerful immunomodulatory effects and mediates recovery. Further investigation of the restorative effects of hNPC transplantation may aid in the development of clinically relevant MS treatments. PMID:24936469

  2. Neural precursor cells induce cell death of high-grade astrocytomas via stimulation of TRPV1

    PubMed Central

    Stock, Kristin; Kumar, Jitender; Synowitz, Michael; Petrosino, Stefania; Imperatore, Roberta; Smith, Ewan St. J.; Wend, Peter; Purfürst, Bettina; Nuber, Ulrike A.; Gurok, Ulf; Matyash, Vitali; Wälzlein, Joo-Hee; Chirasani, Sridhar R.; Dittmar, Gunnar; Cravatt, Benjamin F.; Momma, Stefan; Lewin, Gary R.; Ligresti, Alessia; De Petrocellis, Luciano; Cristino, Luigia; Di Marzo, Vincenzo; Kettenmann, Helmut; Glass, Rainer

    2012-01-01

    Primary astrocytomas of World Health Organization grade 3 and grade 4 (HG-astrocytomas) are preponderant among adults and are almost invariably fatal despite multimodal therapy. Here, we show that the juvenile brain has an endogenous defense mechanism against HG-astrocytomas. Neural precursor cells (NPCs) migrate to HG-astrocytomas, reduce glioma expansion and prolong survival by releasing a group of fatty acid ethanolamides that have agonistic activity on the vanilloid receptor (transient receptor potential vanilloid subfamily member-1; TRPV1). TRPV1 expression is higher in HG-astrocytomas than in tumor-free brain and TRPV1 stimulation triggers tumor cell death via the activating transcription factor-3 (ATF3) controlled branch of the ER stress pathway. The anti-tumorigenic response of NPCs is lost with aging. NPC-mediated tumor suppression can be mimicked in the adult brain by systemic administration of the synthetic vanilloid Arvanil, suggesting that TRPV1 agonists hold potential as new HG-astrocytoma therapeutics. PMID:22820645

  3. Neural precursor cells induce cell death of high-grade astrocytomas through stimulation of TRPV1.

    PubMed

    Stock, Kristin; Kumar, Jitender; Synowitz, Michael; Petrosino, Stefania; Imperatore, Roberta; Smith, Ewan St J; Wend, Peter; Purfürst, Bettina; Nuber, Ulrike A; Gurok, Ulf; Matyash, Vitali; Wälzlein, Joo-Hee; Chirasani, Sridhar R; Dittmar, Gunnar; Cravatt, Benjamin F; Momma, Stefan; Lewin, Gary R; Ligresti, Alessia; De Petrocellis, Luciano; Cristino, Luigia; Di Marzo, Vincenzo; Kettenmann, Helmut; Glass, Rainer

    2012-08-01

    Primary astrocytomas of grade 3 or 4 according to the classification system of the World Health Organization (high-grade astrocytomas or HGAs) are preponderant among adults and are almost invariably fatal despite the use of multimodal therapy. Here we show that the juvenile brain has an endogenous defense mechanism against HGAs. Neural precursor cells (NPCs) migrate to HGAs, reduce glioma expansion and prolong survival time by releasing endovanilloids that activate the vanilloid receptor (transient receptor potential vanilloid subfamily member-1 or TRPV1) on HGA cells. TRPV1 is highly expressed in tumor and weakly expressed in tumor-free brain. TRPV1 stimulation triggers tumor cell death through the branch of the endoplasmic reticulum stress pathway that is controlled by activating transcription factor-3 (ATF3). The antitumorigenic response of NPCs is lost with aging. NPC-mediated tumor suppression can be mimicked in the adult brain by systemic administration of the synthetic vanilloid arvanil, suggesting that TRPV1 agonists have potential as new HGA therapeutics. PMID:22820645

  4. Genetically engineered mouse models of human B-cell precursor leukemias

    PubMed Central

    Hauer, Julia; Borkhardt, Arndt; Sánchez-García, Isidro; Cobaleda, César

    2014-01-01

    B-cell precursor acute lymphoblastic leukemias (pB-ALLs) are the most frequent type of malignancies of the childhood, and also affect an important proportion of adult patients. In spite of their apparent homogeneity, pB-ALL comprises a group of diseases very different both clinically and pathologically, and with very diverse outcomes as a consequence of their biology, and underlying molecular alterations. Their understanding (as a prerequisite for their cure) will require a sustained multidisciplinary effort from professionals coming from many different fields. Among all the available tools for pB-ALL research, the use of animal models stands, as of today, as the most powerful approach, not only for the understanding of the origin and evolution of the disease, but also for the development of new therapies. In this review we go over the most relevant (historically, technically or biologically) genetically engineered mouse models (GEMMs) of human pB-ALLs that have been generated over the last 20 years. Our final aim is to outline the most relevant guidelines that should be followed to generate an “ideal” animal model that could become a standard for the study of human pB-ALL leukemia, and which could be shared among research groups and drug development companies in order to unify criteria for studies like drug testing, analysis of the influence of environmental risk factors, or studying the role of both low-penetrance mutations and cancer susceptibility alterations. PMID:25486471

  5. OXIDATIVE STRESS INDUCES CELL DEATH IN CD-1 MOUSE CRANIAL NEURAL CREST CELLS IN VITRO

    EPA Science Inventory

    OXIDATIVE STRESS INDUCES CELL DEATH IN CD-1 MOUSE CRANIAL NEURAL CREST CELLS IN VITRO. J.B. Smith, K.K. Sulik, E.S. Hunter III. University of North Carolina at Chapel Hill, Chapel Hill, NC 27599.
    The induction of craniofacial defects by ethanol exposure is mediated in part by...

  6. HALOACETIC ACIDS AND KINASE INHIBITORS PERTURB MOUSE NEURAL CREST CELLS IN VITRO

    EPA Science Inventory

    HUNTER, E.S.1, J. SMITH2, J. ANDREWS1. 1 Reproductive Toxicology Division, NHEERL, US EPA, Research Triangle Park and 2 Department of Cell and Developmental Biology, UNC-CH, Chapel Hill, North Carolina. Haloacetic acids and kinase inhibitors perturb mouse neural crest cells in vi...

  7. Astroglial β-Arrestin1-mediated Nuclear Signaling Regulates the Expansion of Neural Precursor Cells in Adult Hippocampus

    PubMed Central

    Tao, Yezheng; Ma, Li; Liao, Zhaohui; Le, Qiumin; Yu, Jialing; Liu, Xing; Li, Haohong; Chen, Yuejun; Zheng, Ping; Yang, Zhengang; Ma, Lan

    2015-01-01

    Adult hippocampal neurogenesis is crucial for preserving normal brain function, but how it is regulated by niche cells is uncertain. Here we show that β-arrestin 1 (β-arr1) in dentate gyrus (DG) regulates neural precursor proliferation. β-arr1 knockout (KO) mice show reduced neural precursor proliferation in subgranular zone (SGZ) which could be rescued by selective viral expression of β-arr1 but not its nuclear-function-deficient mutants under control of hGFAP promotor in DG. Compared with wild type astrocytes, β-arr1 KO astrocytes nurture less neurospheres, and this may be attributed to changed activity of soluble, heat-sensitive excretive factors, such as BMP2. RNA-sequencing reveals that β-arr1 KO DG astrocytes exhibit an aberrant gene expression profile of niche factors, including elevated transcription of Bmp2. Taken together, our data suggest that β-arr1 mediated nuclear signaling regulates the production of excretive factors derived from niche astrocytes and expansion of neural precursors in DG, thus maintaining homeostasis of adult hippocampal neurogenesis. PMID:26500013

  8. Two-photon imaging of remyelination of spinal cord axons by engrafted neural precursor cells in a viral model of multiple sclerosis.

    PubMed

    Greenberg, Milton L; Weinger, Jason G; Matheu, Melanie P; Carbajal, Kevin S; Parker, Ian; Macklin, Wendy B; Lane, Thomas E; Cahalan, Michael D

    2014-06-01

    Neural precursor cells (NPCs) offer a promising approach for treating demyelinating diseases. However, the cellular dynamics that underlie transplanted NPC-mediated remyelination have not been described. Using two-photon imaging of a newly developed ventral spinal cord preparation and a viral model of demyelination, we describe the motility and intercellular interactions of transplanted mouse NPCs expressing green fluorescent protein (GFP) with damaged axons expressing yellow fluorescent protein (YFP). Our findings reveal focal axonal degeneration that occurs in the ventral side of the spinal cord within 1 wk following intracranial instillation with the neurotropic JHM strain of mouse hepatitis virus (JHMV). Axonal damage precedes extensive demyelination and is characterized by swelling along the length of the axon, loss of YFP signal, and transected appearance. NPCs engrafted into spinal cords of JHMV-infected mice exhibited diminished migration velocities and increased proliferation compared with transplanted cells in noninfected mice. NPCs preferentially accumulated within areas of axonal damage, initiated direct contact with axons, and subsequently expressed the myelin proteolipid protein gene, initiating remyelination. These findings indicate that NPCs transplanted into an inflammatory demyelinating microenvironment participate directly in therapeutic outcome through the wrapping of myelin around damaged neurons. PMID:24843159

  9. Phosphorylation Regulates Id2 Degradation and Mediates the Proliferation of Neural Precursor Cells

    PubMed Central

    Sullivan, Jaclyn M.; Havrda, Matthew C.; Kettenbach, Arminja N.; Paolella, Brenton R.; Zhang, Zhonghua; Gerber, Scott A.; Israel, Mark A.

    2016-01-01

    Inhibitor of DNA binding proteins (Id1-Id4) function to inhibit differentiation and promote proliferation of many different cell types. Among the Id family members, Id2 has been most extensively studied in the central nervous system (CNS). Id2 contributes to cultured neural precursor cell (NPC) proliferation as well as to the proliferation of CNS tumors such as glioblastoma that are likely to arise from NPC-like cells. We identified three phosphorylation sites near the N-terminus of Id2 in NPCs. To interrogate the importance of Id2 phosphorylation, Id2−/− NPCs were modified to express wild type (WT) Id2 or an Id2 mutant protein that could not be phosphorylated at the identified sites. We observed that NPCs expressing this mutant lacking phosphorylation near the N-terminus had higher steady-state levels of Id2 when compared to NPCs expressing WT Id2. This elevated level was the result of a longer half-life and reduced proteasome-mediated degradation. Moreover, NPCs expressing constitutively de-phosphorylated Id2 proliferated more rapidly than NPCs expressing WT Id2, a finding consistent with the well-characterized function of Id2 in driving proliferation. Observing that phosphorylation of Id2 modulates the degradation of this important cell-cycle regulator, we sought to identify a phosphatase that would stabilize Id2 enhancing its activity in NPCs and extended our analysis to include human glioblastoma-derived stem cells (GSCs). We found that expression of the phosphatase PP2A altered Id2 levels. Our findings suggest that inhibition of PP2A may be a novel strategy to regulate the proliferation of normal NPCs and malignant GSCs by decreasing Id2 levels. PMID:26756672

  10. Intravenous Administration of Human ES-derived Neural Precursor Cells Attenuates Cuprizone-induced CNS Demyelination

    PubMed Central

    Crocker, Stephen J.; Bajpai, Ruchi; Moore, Craig S.; Frausto, Ricardo F.; Brown, Graham D.; Pagarigan, Roberto R.; Whitton, J. Lindsay; Terskikh, Alexey V.

    2011-01-01

    Aims Previous studies have demonstrated the therapeutic potential for human embryonic stem cell-derived neural precursor cells (hES-NPCs) in autoimmune and genetic animal models of demyelinating diseases. Herein, we tested whether intravenous (i.v) administration of hES-NPCs would impact central nervous system (CNS) demyelination in a cuprizone model of demyelination. Methods C57Bl/6 mice were fed cuprizone (0.2%) for two weeks and then separated into two groups that either received an i.v. injection of hES-NPCs or i.v. administration of media without these cells. After an additional two weeks of dietary cuprizone treatment, CNS tissues were analyzed for detection of transplanted cells and differences in myelination in the region of the corpus callosum (CC). Results Cuprizone-induced demyelination in the CC was significantly reduced in mice treated with hES-NPCs compared with cuprizone-treated controls that did not receive stem cells. hES-NPCs were identified within the brain tissues of treated mice and revealed migration of transplanted cells into the CNS. A limited number of human cells were found to express the mature oligodendrocyte marker, O1, or the astrocyte marker, GFAP. Reduced apoptosis and attenuated microglial and astrocytic responses were also observed in the CC of hES-NPC-treated mice. Conclusions These findings indicated that systemically-administered hES-NPCs migrated from circulation into a demyelinated lesion within the CNS and effectively reduced demyelination. Observed reductions in astrocyte and microglial responses, and (c) the benefit of hES-NPC treatment in this model of myelin injury was not obviously accountable to tissue replacement by exogenously administered cells. PMID:21276029

  11. High mobility group nucleosome-binding family proteins promote astrocyte differentiation of neural precursor cells.

    PubMed

    Nagao, Motoshi; Lanjakornsiripan, Darin; Itoh, Yasuhiro; Kishi, Yusuke; Ogata, Toru; Gotoh, Yukiko

    2014-11-01

    Astrocytes are the most abundant cell type in the mammalian brain and are important for the functions of the central nervous system. Although previous studies have shown that the STAT signaling pathway or its regulators promote the generation of astrocytes from multipotent neural precursor cells (NPCs) in the developing mammalian brain, the molecular mechanisms that regulate the astrocytic fate decision have still remained largely unclear. Here, we show that the high mobility group nucleosome-binding (HMGN) family proteins, HMGN1, 2, and 3, promote astrocyte differentiation of NPCs during brain development. HMGN proteins were expressed in NPCs, Sox9(+) glial progenitors, and GFAP(+) astrocytes in perinatal and adult brains. Forced expression of either HMGN1, 2, or 3 in NPCs in cultures or in the late embryonic neocortex increased the generation of astrocytes at the expense of neurons. Conversely, knockdown of either HMGN1, 2, or 3 in NPCs suppressed astrocyte differentiation and promoted neuronal differentiation. Importantly, overexpression of HMGN proteins did not induce the phosphorylation of STAT3 or activate STAT reporter genes. In addition, HMGN family proteins did not enhance DNA demethylation and acetylation of histone H3 around the STAT-binding site of the gfap promoter. Moreover, knockdown of HMGN family proteins significantly reduced astrocyte differentiation induced by gliogenic signal ciliary neurotrophic factor, which activates the JAK-STAT pathway. Therefore, we propose that HMGN family proteins are novel chromatin regulatory factors that control astrocyte fate decision/differentiation in parallel with or downstream of the JAK-STAT pathway through modulation of the responsiveness to gliogenic signals. PMID:25069414

  12. Predifferentiated GABAergic Neural Precursor Transplants for Alleviation of Dysesthetic Central Pain Following Excitotoxic Spinal Cord Injury

    PubMed Central

    Lee, Jeung Woon; Jergova, Stanislava; Furmanski, Orion; Gajavelli, Shyam; Sagen, Jacqueline

    2012-01-01

    Intraspinal quisqualic acid (QUIS) injury induce (i) mechanical and thermal hyperalgesia, (ii) progressive self-injurious overgrooming of the affected dermatome. The latter is thought to resemble painful dysesthesia observed in spinal cord injury (SCI) patients. We have reported previously loss of endogenous GABA immunoreactive (IR) cells in the superficial dorsal horn of QUIS rats 2 weeks post injury. Further histological evaluation showed that GABA-, glycine-, and synaptic vesicular transporter VIAAT-IR persisted but were substantially decreased in the injured spinal cord. In this study, partially differentiated GABA-IR embryonic neural precursor cells (NPCs) were transplanted into the spinal cord of QUIS rats to reverse overgrooming by replenishing lost inhibitory circuitry. Rat E14 NPCs were predifferentiated in 0.1 ng/ml FGF-2 for 4 h prior to transplantation. In vitro immunocytochemistry of transplant cohort showed large population of GABA-IR NPCs that double labeled with nestin but few colocalized with NeuN, indicating partial maturation. Two weeks following QUIS lesion at T12-L1, and following the onset of overgrooming, NPCs were transplanted into the QUIS lesion sites; bovine adrenal fibroblast cells were used as control. Overgrooming was reduced in >55.5% of NPC grafted animals, with inverse relationship between the number of surviving GABA-IR cells and the size of overgrooming. Fibroblast-control animals showed a progressive worsening of overgrooming. At 3 weeks post-transplantation, numerous GABA-, nestin-, and GFAP-IR cells were present in the lesion site. Surviving grafted GABA-IR NPCs were NeuN+ and GFAP−. These results indicate that partially differentiated NPCs survive and differentiate in vivo into neuronal cells following transplantation into an injured spinal cord. GABA-IR NPC transplants can restore lost dorsal horn inhibitory signaling and are useful in alleviating central pain following SCI. PMID:22754531

  13. Phosphorylation Regulates Id2 Degradation and Mediates the Proliferation of Neural Precursor Cells.

    PubMed

    Sullivan, Jaclyn M; Havrda, Matthew C; Kettenbach, Arminja N; Paolella, Brenton R; Zhang, Zhonghua; Gerber, Scott A; Israel, Mark A

    2016-05-01

    Inhibitor of DNA binding proteins (Id1-Id4) function to inhibit differentiation and promote proliferation of many different cell types. Among the Id family members, Id2 has been most extensively studied in the central nervous system (CNS). Id2 contributes to cultured neural precursor cell (NPC) proliferation as well as to the proliferation of CNS tumors such as glioblastoma that are likely to arise from NPC-like cells. We identified three phosphorylation sites near the N-terminus of Id2 in NPCs. To interrogate the importance of Id2 phosphorylation, Id2(-/-) NPCs were modified to express wild type (WT) Id2 or an Id2 mutant protein that could not be phosphorylated at the identified sites. We observed that NPCs expressing this mutant lacking phosphorylation near the N-terminus had higher steady-state levels of Id2 when compared to NPCs expressing WT Id2. This elevated level was the result of a longer half-life and reduced proteasome-mediated degradation. Moreover, NPCs expressing constitutively de-phosphorylated Id2 proliferated more rapidly than NPCs expressing WT Id2, a finding consistent with the well-characterized function of Id2 in driving proliferation. Observing that phosphorylation of Id2 modulates the degradation of this important cell-cycle regulator, we sought to identify a phosphatase that would stabilize Id2 enhancing its activity in NPCs and extended our analysis to include human glioblastoma-derived stem cells (GSCs). We found that expression of the phosphatase PP2A altered Id2 levels. Our findings suggest that inhibition of PP2A may be a novel strategy to regulate the proliferation of normal NPCs and malignant GSCs by decreasing Id2 levels. Stem Cells 2016;34:1321-1331. PMID:26756672

  14. Systems Genetics Analysis of a Recombinant Inbred Mouse Cell Culture Panel Reveals Wnt Pathway Member Lrp6 as a Regulator of Adult Hippocampal Precursor Cell Proliferation.

    PubMed

    Kannan, Suresh; Nicola, Zeina; Overall, Rupert W; Ichwan, Muhammad; Ramírez-Rodríguez, Gerardo; N Grzyb, Anna; Patone, Giannino; Saar, Kathrin; Hübner, Norbert; Kempermann, Gerd

    2016-03-01

    In much animal research, genetic variation is rather avoided than used as a powerful tool to identify key regulatory genes in complex phenotypes. Adult hippocampal neurogenesis is one such highly complex polygenic trait, for which the understanding of the molecular basis is fragmented and incomplete, and for which novel genetic approaches are needed. In this study, we aimed at marrying the power of the BXD panel, a mouse genetic reference population, with the flexibility of a cell culture model of adult neural precursor proliferation and differentiation. We established adult-derived hippocampal precursor cell cultures from 20 strains of the BXD panel, including the parental strains C57BL/6J and DBA/2J. The rates of cell proliferation and neuronal differentiation were measured, and transcriptional profiles were obtained from proliferating cultures. Together with the published genotypes of all lines, these data allowed a novel systems genetics analysis combining quantitative trait locus analysis with transcript expression correlation at a cellular level to identify genes linked with the differences in proliferation. In a proof-of-principle analysis, we identified Lrp6, the gene encoding the coreceptor to Frizzled in the Wnt pathway, as a potential negative regulator of precursor proliferation. Overexpression and siRNA silencing confirmed the regulatory role of Lrp6. As well as adding to our knowledge of the pathway surrounding Wnt in adult hippocampal neurogenesis, this finding allows the new appreciation of a negative regulator within this system. In addition, the resource and associated methodology will allow the integration of regulatory mechanisms at a systems level. Stem Cells 2016;34:674-684. PMID:26840599

  15. Metformin Acts on Two Different Molecular Pathways to Enhance Adult Neural Precursor Proliferation/Self-Renewal and Differentiation

    PubMed Central

    Fatt, Michael; Hsu, Karolynn; He, Ling; Wondisford, Fredric; Miller, Freda D.; Kaplan, David R.; Wang, Jing

    2015-01-01

    Summary The recruitment of endogenous adult neural stem cells for brain repair is a promising regenerative therapeutic strategy. This strategy involves stimulation of multiple stages of adult neural stem cell development, including proliferation, self-renewal, and differentiation. Currently, there is a lack of a single therapeutic approach that can act on these multiple stages of adult neural stem cell development to enhance neural regeneration. Here we show that metformin, an FDA-approved diabetes drug, promotes proliferation, self-renewal, and differentiation of adult neural precursors (NPCs). Specifically, we show that metformin enhances adult NPC proliferation and self-renewal dependent upon the p53 family member and transcription factor TAp73, while it promotes neuronal differentiation of these cells by activating the AMPK-aPKC-CBP pathway. Thus, metformin represents an optimal candidate neuro-regenerative agent that is capable of not only expanding the adult NPC population but also subsequently driving them toward neuronal differentiation by activating two distinct molecular pathways. PMID:26677765

  16. Expression of PROKR1 and PROKR2 in Human Enteric Neural Precursor Cells and Identification of Sequence Variants Suggest a Role in HSCR

    PubMed Central

    Ruiz-Ferrer, Macarena; Torroglosa, Ana; Núñez-Torres, Rocío; de Agustín, Juan Carlos; Antiñolo, Guillermo; Borrego, Salud

    2011-01-01

    Background The enteric nervous system (ENS) is entirely derived from neural crest and its normal development is regulated by specific molecular pathways. Failure in complete ENS formation results in aganglionic gut conditions such as Hirschsprung's disease (HSCR). Recently, PROKR1 expression has been demonstrated in mouse enteric neural crest derived cells and Prok-1 was shown to work coordinately with GDNF in the development of the ENS. Principal Findings In the present report, ENS progenitors were isolated and characterized from the ganglionic gut from children diagnosed with and without HSCR, and the expression of prokineticin receptors was examined. Immunocytochemical analysis of neurosphere-forming cells demonstrated that both PROKR1 and PROKR2 were present in human enteric neural crest cells. In addition, we also performed a mutational analysis of PROKR1, PROKR2, PROK1 and PROK2 genes in a cohort of HSCR patients, evaluating them for the first time as susceptibility genes for the disease. Several missense variants were detected, most of them affecting highly conserved amino acid residues of the protein and located in functional domains of both receptors, which suggests a possible deleterious effect in their biological function. Conclusions Our results suggest that not only PROKR1, but also PROKR2 might mediate a complementary signalling to the RET/GFRα1/GDNF pathway supporting proliferation/survival and differentiation of precursor cells during ENS development. These findings, together with the detection of sequence variants in PROKR1, PROK1 and PROKR2 genes associated to HSCR and, in some cases in combination with RET or GDNF mutations, provide the first evidence to consider them as susceptibility genes for HSCR. PMID:21858136

  17. Mouse as a model for multifactorial inheritance of neural tube defects.

    PubMed

    Zohn, Irene E

    2012-06-01

    Neural tube defects (NTDs) such as spina bifida and anencephaly are some of the most common structural birth defects found in humans. These defects occur due to failures of neurulation, a process where the flat neural plate rolls into a tube. In spite of their prevalence, the causes of NTDs are poorly understood. The multifactorial threshold model best describes the pattern of inheritance of NTDs where multiple undefined gene variants interact with environmental factors to cause an NTD. To date, mouse models have implicated a multitude of genes as required for neurulation, providing a mechanistic understanding of the cellular and molecular pathways that control neurulation. However, the majority of these mouse models exhibit NTDs with a Mendelian pattern of inheritance. Still, many examples of multifactorial inheritance have been demonstrated in mouse models of NTDs. These include null and hypomorphic alleles of neurulation genes that interact in a complex fashion with other genetic mutations or environmental factors to cause NTDs. These models have implicated several genes and pathways for testing as candidates for the genetic basis of NTDs in humans, resulting in identification of putative pathogenic mutations in some patients. Mouse models also provide an experimental paradigm to gain a mechanistic understanding of the environmental factors that influence NTD occurrence, such as folic acid and maternal diabetes, and have led to the discovery of additional preventative nutritional supplements such as inositol. This review provides examples of how multifactorial inheritance of NTDs can be modeled in the mouse. PMID:22692891

  18. Genetic dissection of GABAergic neural circuits in mouse neocortex

    PubMed Central

    Taniguchi, Hiroki

    2014-01-01

    Diverse and flexible cortical functions rely on the ability of neural circuits to perform multiple types of neuronal computations. GABAergic inhibitory interneurons significantly contribute to this task by regulating the balance of activity, synaptic integration, spiking, synchrony, and oscillation in a neural ensemble. GABAergic interneurons display a high degree of cellular diversity in morphology, physiology, connectivity, and gene expression. A considerable number of subtypes of GABAergic interneurons diversify modes of cortical inhibition, enabling various types of information processing in the cortex. Thus, comprehensively understanding fate specification, circuit assembly, and physiological function of GABAergic interneurons is a key to elucidate the principles of cortical wiring and function. Recent advances in genetically encoded molecular tools have made a breakthrough to systematically study cortical circuitry at the molecular, cellular, circuit, and whole animal levels. However, the biggest obstacle to fully applying the power of these to analysis of GABAergic circuits was that there were no efficient and reliable methods to express them in subtypes of GABAergic interneurons. Here, I first summarize cortical interneuron diversity and current understanding of mechanisms, by which distinct classes of GABAergic interneurons are generated. I then review recent development in genetically encoded molecular tools for neural circuit research, and genetic targeting of GABAergic interneuron subtypes, particularly focusing on our recent effort to develop and characterize Cre/CreER knockin lines. Finally, I highlight recent success in genetic targeting of chandelier cells, the most unique and distinct GABAergic interneuron subtype, and discuss what kind of questions need to be addressed to understand development and function of cortical inhibitory circuits. PMID:24478631

  19. Kinesin Light Chain 1 Suppression Impairs Human Embryonic Stem Cell Neural Differentiation and Amyloid Precursor Protein Metabolism

    PubMed Central

    Killian, Rhiannon L.; Flippin, Jessica D.; Herrera, Cheryl M.; Almenar-Queralt, Angels; Goldstein, Lawrence S. B.

    2012-01-01

    The etiology of sporadic Alzheimer disease (AD) is largely unknown, although evidence implicates the pathological hallmark molecules amyloid beta (Aβ) and phosphorylated Tau. Work in animal models suggests that altered axonal transport caused by Kinesin-1 dysfunction perturbs levels of both Aβ and phosphorylated Tau in neural tissues, but the relevance of Kinesin-1 dependent functions to the human disease is unknown. To begin to address this issue, we generated human embryonic stem cells (hESC) expressing reduced levels of the kinesin light chain 1 (KLC1) Kinesin-1 subunit to use as a source of human neural cultures. Despite reduction of KLC1, undifferentiated hESC exhibited apparently normal colony morphology and pluripotency marker expression. Differentiated neural cultures derived from KLC1-suppressed hESC contained neural rosettes but further differentiation revealed obvious morphological changes along with reduced levels of microtubule-associated neural proteins, including Tau and less secreted Aβ, supporting the previously established connection between KLC1, Tau and Aβ. Intriguingly, KLC1-suppressed neural precursors (NPs), isolated using a cell surface marker signature known to identify cells that give rise to neurons and glia, unlike control cells, failed to proliferate. We suggest that KLC1 is required for normal human neural differentiation, ensuring proper metabolism of AD-associated molecules APP and Tau and for proliferation of NPs. Because impaired APP metabolism is linked to AD, this human cell culture model system will not only be a useful tool for understanding the role of KLC1 in regulating the production, transport and turnover of APP and Tau in neurons, but also in defining the essential function(s) of KLC1 in NPs and their progeny. This knowledge should have important implications for human neurodevelopmental and neurodegenerative diseases. PMID:22272245

  20. Neurodifferentiating potential of 8-prenylnaringenin and related compounds in neural precursor cells and correlation with estrogen-like activity.

    PubMed

    Urmann, Corinna; Oberbauer, Eleni; Couillard-Després, Sébastien; Aigner, Ludwig; Riepl, Herbert

    2015-03-01

    Neurodegenerative diseases are an increasing burden for our ageing societies; there is an as yet unmet need for the development of effective therapies. Neurogenesis, i.e., the generation of new neurons in the adult brain from neural stem cells, has received increasing attention since it offers the potential for endogenous brain repair and functional regeneration. Adult neurogenesis is partially under the control of sex hormones such as estradiol, and boosting neurogenesis with estradiol in animals correlates with cognitive improvement. 8-Prenylnaringenin imitates as highly potent phytoestrogen the effects of estradiol. Here, we studied the potential of 8-prenylnaringenin, 6-prenylnaringenin, and related compounds on differentiation induction in vitro using neural precursor cells transiently transfected with a doublecortin promoter luciferase construct, which was recently shown to indicate neuronal fate and differentiation. The flavanones 8-prenylnaringenin and 6-prenylnaringenin showed slight activity in this assay but significant activity by immunostaining. Although the estrogen-like activities of 8-prenylnaringenin and 6-prenylnaringenin are very different, the activity in differentiation induction is similar. Interestingly, also some prenylflavonoids with extended prenyl groups, e.g., a geranyl group, showed increased differentiation activity, while estrogen-like activity is decreased. This allows the conclusion that estrogen-like activity of prenylflavanones does not correlate directly with the activity of differentiation induction in neural precursor cells. PMID:25714726

  1. Novel Mode of Defective Neural Tube Closure in the Non-Obese Diabetic (NOD) Mouse Strain

    PubMed Central

    Salbaum, J. Michael; Kruger, Claudia; MacGowan, Jacalyn; Herion, Nils J.; Burk, David; Kappen, Claudia

    2015-01-01

    Failure to close the neural tube results in birth defects, with severity ranging from spina bifida to lethal anencephaly. Few genetic risk factors for neural tube defects are known in humans, highlighting the critical role of environmental risk factors, such as maternal diabetes. Yet, it is not well understood how altered maternal metabolism interferes with embryonic development, and with neurulation in particular. We present evidence from two independent mouse models of diabetic pregnancy that identifies impaired migration of nascent mesodermal cells in the primitive streak as the morphogenetic basis underlying the pathogenesis of neural tube defects. We conclude that perturbed gastrulation not only explains the neurulation defects, but also provides a unifying etiology for the broad spectrum of congenital malformations in diabetic pregnancies. PMID:26593875

  2. Novel Mode of Defective Neural Tube Closure in the Non-Obese Diabetic (NOD) Mouse Strain.

    PubMed

    Salbaum, J Michael; Kruger, Claudia; MacGowan, Jacalyn; Herion, Nils J; Burk, David; Kappen, Claudia

    2015-01-01

    Failure to close the neural tube results in birth defects, with severity ranging from spina bifida to lethal anencephaly. Few genetic risk factors for neural tube defects are known in humans, highlighting the critical role of environmental risk factors, such as maternal diabetes. Yet, it is not well understood how altered maternal metabolism interferes with embryonic development, and with neurulation in particular. We present evidence from two independent mouse models of diabetic pregnancy that identifies impaired migration of nascent mesodermal cells in the primitive streak as the morphogenetic basis underlying the pathogenesis of neural tube defects. We conclude that perturbed gastrulation not only explains the neurulation defects, but also provides a unifying etiology for the broad spectrum of congenital malformations in diabetic pregnancies. PMID:26593875

  3. Cellular basis of neuroepithelial bending during mouse spinal neural tube closure

    PubMed Central

    McShane, Suzanne G.; Molè, Matteo A.; Savery, Dawn; Greene, Nicholas D. E; Tam, Patrick P.L.; Copp, Andrew J.

    2015-01-01

    Summary Bending of the neural plate at paired dorsolateral hinge points (DLHPs) is required for neural tube closure in the spinal region of the mouse embryo. As a step towards understanding the morphogenetic mechanism of DLHP development, we examined variations in neural plate cellular architecture and proliferation during closure. Neuroepithelial cells within the median hinge point (MHP) contain nuclei that are mainly basally located and undergo relatively slow proliferation, with a 7 h cell cycle length. In contrast, cells in the dorsolateral neuroepithelium, including the DLHP, exhibit nuclei distributed throughout the apico-basal axis and undergo rapid proliferation, with a 4 h cell cycle length. As the neural folds elevate, cell numbers increase to a greater extent in the dorsolateral neural plate that contacts the surface ectoderm, compared with the more ventromedial neural plate where cells contact paraxial mesoderm and notochord. This marked increase in dorsolateral cell number cannot be accounted for solely on the basis of enhanced cell proliferation in this region. We hypothesised that neuroepithelial cells may translocate in a ventral-to-dorsal direction as DLHP formation occurs, and this was confirmed by vital cell labelling in cultured embryos. The translocation of cells into the neural fold, together with its more rapid cell proliferation, leads to an increase in cell density dorsolaterally compared with the more ventromedial neural plate. These findings suggest a model in which DLHP formation may proceed through ‘buckling’ of the neuroepithelium at a dorso-ventral boundary marked by a change in cell-packing density. PMID:26079577

  4. Embryonic Nkx2.1-expressing neural precursor cells contribute to the regional heterogeneity of adult V-SVZ neural stem cells.

    PubMed

    Delgado, Ryan N; Lim, Daniel A

    2015-11-15

    The adult ventricular-subventricular zone (V-SVZ) of the lateral ventricle produces several subtypes of olfactory bulb (OB) interneurons throughout life. Neural stem cells (NSCs) within this zone are heterogeneous, with NSCs located in different regions of the lateral ventricle wall generating distinct OB interneuron subtypes. The regional expression of specific transcription factors appears to correspond to such geographical differences in the developmental potential of V-SVZ NSCs. However, the transcriptional definition and developmental origin of V-SVZ NSC regional identity are not well understood. In this study, we found that a population of NSCs in the ventral region of the V-SVZ expresses the transcription factor Nkx2.1 and is derived from Nkx2.1-expressing (Nkx2.1+) embryonic precursors. To follow the fate of Nkx2.1+ cells and their progeny in vivo, we used mice with an Nkx2.1-CreER "knock-in" allele. Nkx2.1+ V-SVZ NSCs labeled in adult mice generated interneurons for the deep granule cell layer of the OB. Embryonic brain Nkx2.1+ precursors labeled at embryonic day 12.5 gave rise to Nkx2.1+ NSCs of the ventral V-SVZ in postnatal and adult mice. Thus, embryonic Nkx2.1+ neural precursors give rise to a population of Nkx2.1+ NSCs in the ventral V-SVZ where they contribute to the regional heterogeneity of V-SVZ NSCs. PMID:26387477

  5. Sonic Hedgehog Controls the Phenotypic Fate and Therapeutic Efficacy of Grafted Neural Precursor Cells in a Model of Nigrostriatal Neurodegeneration

    PubMed Central

    Madhavan, Lalitha; Daley, Brian F.; Davidson, Beverly L.; Boudreau, Ryan L.; Lipton, Jack W.; Cole-Strauss, Allyson; Steece-Collier, Kathy; Collier, Timothy J.

    2015-01-01

    The expression of soluble growth and survival promoting factors by neural precursor cells (NPCs) is suggested to be a prominent mechanism underlying the protective and regenerative effects of these cells after transplantation. Nevertheless, how and to what extent specific NPC-expressed factors contribute to therapeutic effects is not well understood. Using RNA silencing, the current study investigated the roles of two donor NPC molecules, namely glial cell-line derived neurotrophic factor (GDNF) and sonic hedgehog (SHH), in the protection of substantia nigra dopamine neurons in rats treated with 6-hydroxydopamine (6-OHDA). Analyses indicate that as opposed to the knock-down of GDNF, SHH inhibition caused a profound decline in nigrostriatal neuroprotection. Further, SHH silencing also curbed endogenous neurogenesis and the migration of host brdU+/dcx+ neural precursors into the striatum, which was present in the animals receiving control or GDNF silenced NPCs. A change in graft phenotype, mainly reflected by a reduced proportion of undifferentiated nestin+ cells, as well as a significantly greater host microglial activity, suggested an important role for these processes in the attenuation of neuroprotection and neurogenesis upon SHH silencing. Overall these studies reveal core mechanisms fundamental to grafted NPC-based therapeutic effects, and delineate the particular contributions of two graft-expressed molecules, SHH and GDNF, in mediating midbrain dopamine neuron protection, and host plasticity after NPC transplantation. PMID:26340267

  6. Physical exercise counteracts MPTP-induced changes in neural precursor cell proliferation in the hippocampus and restores spatial learning but not memory performance in the water maze.

    PubMed

    Klein, C; Rasińska, J; Empl, L; Sparenberg, M; Poshtiban, A; Hain, E G; Iggena, D; Rivalan, M; Winter, Y; Steiner, B

    2016-07-01

    Parkinson's disease (PD) is characterized by a continuous loss of dopaminergic neurons in the substantia nigra, which not only leads to characteristic motor symptoms but also to cognitive impairments. Physical exercise has been shown to improve hippocampus-dependent cognitive functions in PD patients. Animal studies have demonstrated the involvement of adult hippocampal neurogenesis in exercise-induced improvements of visuo-spatial learning and memory. Here, we investigated the direct impact of voluntary wheel running on hippocampal neurogenesis and spatial learning and memory in the Morris water maze (MWM) using the1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD. We also analyzed striatal and hippocampal dopamine transmission and mRNA expression levels of dopamine receptors. We show that MPTP-induced spatial learning deficits were alleviated by short-term physical exercise but not MPTP-induced spatial memory impairments in either exercise intervention group. Neural precursor proliferation was transiently altered in MPTP-treated mice, while the cell survival was increased by exercise. Dopamine was progressively depleted by MPTP and its turnover altered by exercise. In addition, gene expression of dopamine receptor D1/D5 was transiently upregulated following MPTP treatment but not affected by physical exercise. Our findings suggest that physical exercise benefits spatial learning but not memory performance in the MWM after MPTP-induced dopamine depletion by restoring precursor cell proliferation in the hippocampus and influencing dopamine transmission. This adds to the understanding of cognitive decline and mechanisms for potential improvements by physical exercise in PD patients. PMID:27012392

  7. Activating Endogenous Neural Precursor Cells Using Metformin Leads to Neural Repair and Functional Recovery in a Model of Childhood Brain Injury.

    PubMed

    Dadwal, Parvati; Mahmud, Neemat; Sinai, Laleh; Azimi, Ashkan; Fatt, Michael; Wondisford, Fredric E; Miller, Freda D; Morshead, Cindi M

    2015-08-11

    The development of cell replacement strategies to repair the injured brain has gained considerable attention, with a particular interest in mobilizing endogenous neural stem and progenitor cells (known as neural precursor cells [NPCs]) to promote brain repair. Recent work demonstrated metformin, a drug used to manage type II diabetes, promotes neurogenesis. We sought to determine its role in neural repair following brain injury. We find that metformin administration activates endogenous NPCs, expanding the size of the NPC pool and promoting NPC migration and differentiation in the injured neonatal brain in a hypoxia-ischemia (H/I) injury model. Importantly, metformin treatment following H/I restores sensory-motor function. Lineage tracking reveals that metformin treatment following H/I causes an increase in the absolute number of subependyma-derived NPCs relative to untreated H/I controls in areas associated with sensory-motor function. Hence, activation of endogenous NPCs is a promising target for therapeutic intervention in childhood brain injury models. PMID:26235894

  8. Activating Endogenous Neural Precursor Cells Using Metformin Leads to Neural Repair and Functional Recovery in a Model of Childhood Brain Injury

    PubMed Central

    Dadwal, Parvati; Mahmud, Neemat; Sinai, Laleh; Azimi, Ashkan; Fatt, Michael; Wondisford, Fredric E.; Miller, Freda D.; Morshead, Cindi M.

    2015-01-01

    Summary The development of cell replacement strategies to repair the injured brain has gained considerable attention, with a particular interest in mobilizing endogenous neural stem and progenitor cells (known as neural precursor cells [NPCs]) to promote brain repair. Recent work demonstrated metformin, a drug used to manage type II diabetes, promotes neurogenesis. We sought to determine its role in neural repair following brain injury. We find that metformin administration activates endogenous NPCs, expanding the size of the NPC pool and promoting NPC migration and differentiation in the injured neonatal brain in a hypoxia-ischemia (H/I) injury model. Importantly, metformin treatment following H/I restores sensory-motor function. Lineage tracking reveals that metformin treatment following H/I causes an increase in the absolute number of subependyma-derived NPCs relative to untreated H/I controls in areas associated with sensory-motor function. Hence, activation of endogenous NPCs is a promising target for therapeutic intervention in childhood brain injury models. PMID:26235894

  9. The protocol for the isolation and cryopreservation of osteoclast precursors from mouse bone marrow and spleen.

    PubMed

    Boraschi-Diaz, Iris; Komarova, Svetlana V

    2016-01-01

    Osteoclasts are responsible for physiological bone remodeling as well as pathological bone destruction in osteoporosis, periodontitis and rheumatoid arthritis, and thus represent a pharmacological target for drug development. We aimed to characterize and compare the cytokine-induced osteoclastogenesis of bone marrow and spleen precursors. Established protocols used to generate osteoclasts from bone marrow were modified to examine osteoclastogenesis of the spleen cells of healthy mice. Osteoclast formation was successfully induced from spleen precursors using receptor activator of nuclear factor κB ligand (50 ng/ml) and macrophage colony stimulating factor (50 ng/ml). Compared to bone marrow cultures, differentiation from spleen required a longer cultivation time (9 days for spleen, as compared to 5 days for marrow cultures) and a higher plating density of non-adherent cells (75,000/cm(2) for spleen, as compared to 50,000/cm(2) for bone marrow). Osteoclasts generated from spleen precursors expressed osteoclast marker genes calcitonin receptor, cathepsin K and matrix metalloproteinase 9 and were capable of resorbing hydroxyapatite. The differentiation capacity of spleen and bone marrow precursors was comparable for BALB/c, C57BL/6 and FVB mice. We also developed and tested a cryopreservation protocol for the osteoclast precursors. While 70-80 % of cells were lost during the first week of freezing, during the subsequent 5 weeks the losses were within 2-5 % per week. Osteoclastogenesis from the recovered bone marrow precursors was successful up to 5 weeks after freezing. Spleen precursors retained their osteoclastogenic capacity for 1 week after freezing, but not thereafter. The described protocol is useful for the studies of genetically modified animals as well as for screening new osteoclast-targeting therapeutics. PMID:25245056

  10. Stroke Increases Neural Stem Cells and Angiogenesis in the Neurogenic Niche of the Adult Mouse

    PubMed Central

    Zhang, Rui Lan; Chopp, Michael; Roberts, Cynthia; Liu, Xianshuang; Wei, Min; Nejad-Davarani, Siamak P.; Wang, Xinli; Zhang, Zheng Gang

    2014-01-01

    The unique cellular and vascular architecture of the adult ventricular-subventricular zone (V/SVZ) neurogenic niche plays an important role in regulating neural stem cell function. However, the in vivo identification of neural stem cells and their relationship to blood vessels within this niche in response to stroke remain largely unknown. Using whole-mount preparation of the lateral ventricle wall, we examined the architecture of neural stem cells and blood vessels in the V/SVZ of adult mouse over the course of 3 months after onset of focal cerebral ischemia. Stroke substantially increased the number of glial fibrillary acidic protein (GFAP) positive neural stem cells that are in contact with the cerebrospinal fluid (CSF) via their apical processes at the center of pinwheel structures formed by ependymal cells residing in the lateral ventricle. Long basal processes of these cells extended to blood vessels beneath the ependymal layer. Moreover, stroke increased V/SVZ endothelial cell proliferation from 2% in non-ischemic mice to 12 and 15% at 7 and 14 days after stroke, respectively. Vascular volume in the V/SVZ was augmented from 3% of the total volume prior to stroke to 6% at 90 days after stroke. Stroke-increased angiogenesis was closely associated with neuroblasts that expanded to nearly encompass the entire lateral ventricular wall in the V/SVZ. These data indicate that stroke induces long-term alterations of the neural stem cell and vascular architecture of the adult V/SVZ neurogenic niche. These post-stroke structural changes may provide insight into neural stem cell mediation of stroke-induced neurogenesis through the interaction of neural stem cells with proteins in the CSF and their sub-ependymal neurovascular interaction. PMID:25437857

  11. Wnt signaling regulates smooth muscle precursor development in the mouse lung via a tenascin C/PDGFR pathway.

    PubMed

    Cohen, Ethan David; Ihida-Stansbury, Kaori; Lu, Min Min; Panettieri, Reynold A; Jones, Peter Lloyd; Morrisey, Edward E

    2009-09-01

    Paracrine signaling from lung epithelium to the surrounding mesenchyme is important for lung SMC development and function and is a contributing factor in an array of pulmonary diseases such as bronchopulmonary dysplasia, pulmonary hypertension, and asthma. Wnt7b, which is exclusively expressed in the lung epithelium, is important for lung vascular smooth muscle integrity, but the underlying mechanism by which Wnt signaling regulates lung SMC development is unclear. In this report, we have demonstrated that Wnt7b regulates a program of mesenchymal differentiation in the mouse lung that is essential for SMC development. Genetic loss-of-function studies showed that Wnt7b and beta-catenin were required for expression of Pdgfralpha and Pdgfrbeta and proliferation in pulmonary SMC precursors. In contrast, gain-of-function studies showed that activation of Wnt signaling increased the expression of both Pdgfralpha and Pdgfrbeta as well as the proliferation of SMC precursors. We further showed that the effect on Pdgfr expression was, in part, mediated by direct transcriptional regulation of the ECM protein tenascin C (Tnc), which was necessary and sufficient for Pdgfralpha/beta expression in lung explants. Moreover, this pathway was highly upregulated in a mouse model of asthma and in lung tissue from patients with pulmonary hypertension. Together, these data define a Wnt/Tnc/Pdgfr signaling axis that is critical for smooth muscle development and disease progression in the lung. PMID:19690384

  12. Different Mechanisms Must Be Considered to Explain the Increase in Hippocampal Neural Precursor Cell Proliferation by Physical Activity

    PubMed Central

    Overall, Rupert W.; Walker, Tara L.; Fischer, Tim J.; Brandt, Moritz D.; Kempermann, Gerd

    2016-01-01

    The number of proliferating neural precursor cells in the adult hippocampus is strongly increased by physical activity. The mechanisms through which this behavioral stimulus induces cell proliferation, however, are not yet understood. In fact, even the mode of proliferation of the stem and progenitor cells is not exactly known. Evidence exists for several mechanisms including cell cycle shortening, reduced cell death and stem cell recruitment, but as yet no model can account for all observations. An appreciation of how the cells proliferate, however, is crucial to our ability to model the neurogenic process and predict its behavior in response to pro-neurogenic stimuli. In a recent study, we addressed modulation of the cell cycle length as one possible mode of regulation of precursor cell proliferation in running mice. Our results indicated that the observed increase in number of proliferating cells could not be explained through a shortening of the cell cycle. We must therefore consider other mechanisms by which physical activity leads to enhanced precursor cell proliferation. Here we review the evidence for and against several different hypotheses and discuss the implications for future research in the field. PMID:27536215

  13. Differential Effects of Isoxazole-9 on Neural Stem/Progenitor Cells, Oligodendrocyte Precursor Cells, and Endothelial Progenitor Cells

    PubMed Central

    Maki, Takakuni; Shindo, Akihiro; Osumi, Noriko; Zhao, Jing; Lin, Hong; Holder, Julie C.; Chuang, Tsu Tshen; McNeish, John D.; Arai, Ken; Lo, Eng H.

    2015-01-01

    Adult mammalian brain can be plastic after injury and disease. Therefore, boosting endogenous repair mechanisms would be a useful therapeutic approach for neurological disorders. Isoxazole-9 (Isx-9) has been reported to enhance neurogenesis from neural stem/progenitor cells (NSPCs). However, the effects of Isx-9 on other types of progenitor/precursor cells remain mostly unknown. In this study, we investigated the effects of Isx-9 on the three major populations of progenitor/precursor cells in brain: NSPCs, oligodendrocyte precursor cells (OPCs), and endothelial progenitor cells (EPCs). Cultured primary NSPCs, OPCs, or EPCs were treated with various concentrations of Isx-9 (6.25, 12.5, 25, 50 μM), and their cell numbers were counted in a blinded manner. Isx-9 slightly increased the number of NSPCs and effectively induced neuronal differentiation of NSPCs. However, Isx-9 significantly decreased OPC number in a concentration-dependent manner, suggesting cytotoxicity. Isx-9 did not affect EPC cell number. But in a matrigel assay of angiogenesis, Isx-9 significantly inhibited tube formation in outgrowth endothelial cells derived from EPCs. This potential anti-tube-formation effect of Isx-9 was confirmed in a brain endothelial cell line. Taken together, our data suggest that mechanisms and targets for promoting stem/progenitor cells in the central nervous system may significantly differ between cell types. PMID:26407349

  14. Neural stem cell transplantation enhances mitochondrial biogenesis in a transgenic mouse model of Alzheimer's disease-like pathology.

    PubMed

    Zhang, Wei; Gu, Guo-Jun; Shen, Xing; Zhang, Qi; Wang, Gang-Min; Wang, Pei-Jun

    2015-03-01

    Mitochondrial dysfunction, especially a defect in mitochondrial biogenesis, is an early and prominent feature of Alzheimer's disease (AD). Previous studies demonstrated that the number of mitochondria is significantly reduced in susceptible hippocampal neurons from AD patients. Neural stem cell (NSC) transplantation in AD-like mice can compensate for the neuronal loss resulting from amyloid-beta protein deposition. The effects of NSC transplantation on mitochondrial biogenesis and cognitive function in AD-like mice, however, are poorly understood. In this study, we injected NSCs or vehicle into 12-month-old amyloid precursor protein (APP)/PS1 transgenic mice, a mouse model of AD-like pathology. The effects of NSC transplantation on cognitive function, the amount of mitochondrial DNA, the expression of mitochondrial biogenesis factors and mitochondria-related proteins, and mitochondrial morphology were investigated. Our results show that in NSC-injected APP/PS1 (Tg-NSC) mice, the cognitive function, number of mitochondria, and expression of mitochondria-related proteins, specifically the mitochondrial fission factors (dynamin-related protein 1 [Drp1] and fission 1 [Fis1]) and the mitochondrial fusion factor optic atrophy 1 (OPA1), were significantly increased compared with those in age-matched vehicle-injected APP/PS1 (Tg-Veh) mice, whereas the expression of mitochondrial fusion factors mitofusion 1 (Mfn1) and Mfn2 was significantly decreased. These data indicate that NSC transplantation may enhance mitochondria biogenesis and further rescue cognitive deficits in AD-like mice. PMID:25582749

  15. Differential transgene expression patterns in Alzheimer mouse models revealed by novel human amyloid precursor protein-specific antibodies.

    PubMed

    Höfling, Corinna; Morawski, Markus; Zeitschel, Ulrike; Zanier, Elisa R; Moschke, Katrin; Serdaroglu, Alperen; Canneva, Fabio; von Hörsten, Stephan; De Simoni, Maria-Grazia; Forloni, Gianluigi; Jäger, Carsten; Kremmer, Elisabeth; Roßner, Steffen; Lichtenthaler, Stefan F; Kuhn, Peer-Hendrik

    2016-10-01

    Alzheimer's disease (AD) is histopathologically characterized by neurodegeneration, the formation of intracellular neurofibrillary tangles and extracellular Aβ deposits that derive from proteolytic processing of the amyloid precursor protein (APP). As rodents do not normally develop Aβ pathology, various transgenic animal models of AD were designed to overexpress human APP with mutations favouring its amyloidogenic processing. However, these mouse models display tremendous differences in the spatial and temporal appearance of Aβ deposits, synaptic dysfunction, neurodegeneration and the manifestation of learning deficits which may be caused by age-related and brain region-specific differences in APP transgene levels. Consequentially, a comparative temporal and regional analysis of the pathological effects of Aβ in mouse brains is difficult complicating the validation of therapeutic AD treatment strategies in different mouse models. To date, no antibodies are available that properly discriminate endogenous rodent and transgenic human APP in brains of APP-transgenic animals. Here, we developed and characterized rat monoclonal antibodies by immunohistochemistry and Western blot that detect human but not murine APP in brains of three APP-transgenic mouse and one APP-transgenic rat model. We observed remarkable differences in expression levels and brain region-specific expression of human APP among the investigated transgenic mouse lines. This may explain the differences between APP-transgenic models mentioned above. Furthermore, we provide compelling evidence that our new antibodies specifically detect endogenous human APP in immunocytochemistry, FACS and immunoprecipitation. Hence, we propose these antibodies as standard tool for monitoring expression of endogenous or transfected APP in human cells and APP expression in transgenic animals. PMID:27470171

  16. Mouse vision as a gateway for understanding how experience shapes neural circuits

    PubMed Central

    Priebe, Nicholas J.; McGee, Aaron W.

    2014-01-01

    Genetic programs controlling ontogeny drive many of the essential connectivity patterns within the brain. Yet it is activity, derived from the experience of interacting with the world, that sculpts the precise circuitry of the central nervous system. Such experience-dependent plasticity has been observed throughout the brain but has been most extensively studied in the neocortex. A prime example of this refinement of neural circuitry is found in primary visual cortex (V1), where functional connectivity changes have been observed both during development and in adulthood. The mouse visual system has become a predominant model for investigating the principles that underlie experience-dependent plasticity, given the general conservation of visual neural circuitry across mammals as well as the powerful tools and techniques recently developed for use in rodent. The genetic tractability of mice has permitted the identification of signaling pathways that translate experience-driven activity patterns into changes in circuitry. Further, the accessibility of visual cortex has allowed neural activity to be manipulated with optogenetics and observed with genetically-encoded calcium sensors. Consequently, mouse visual cortex has become one of the dominant platforms to study experience-dependent plasticity. PMID:25324730

  17. Transplantation of subventricular zone neural precursors induces an endogenous precursor cell response in a rat model of Parkinson’s disease

    PubMed Central

    Madhavan, Lalitha; Daley, Brian F; Paumier, Katrina L; Collier, Timothy J

    2009-01-01

    Realistically, future stem cell therapies for neurological conditions including Parkinson’s disease (PD) will most probably entail combination treatment strategies, involving both the stimulation of endogenous cells and transplantation. Therefore, this study investigates these two modes of neural precursor cell (NPC) therapy in concert in order to determine their interrelationships in a rat PD model. Human placental alkaline phosphatase (hPAP) labeled NPCs were transplanted unilaterally into host rats which were subsequently infused ipsilaterally with 6-hydroxydopamine (6-OHDA). The reaction of host NPCs to the transplantation and 6-OHDA was tracked by bromodeoxyuridine labeling. Two weeks after transplantation, in animals transplanted with NPCs, we found evidence of elevated host subventricular zone NPC proliferation, neurogenesis, and migration to the graft site. In these animals, we also observed a significant preservation of striatal tyrosine hydroxylase (TH) expression and substantia nigra TH cell number. We have seen no evidence that neuroprotection is a product of DA neuron replacement by NPC-derived cells. Rather, the NPCs expressed glial cell line-derived neurotrophic factor (GDNF), sonic hedgehog (Shh) and stromal cell derived factor 1 alpha (SDF1α) providing a molecular basis for the observed neuroprotection and endogenous NPC response to transplantation. In summary, our data suggests plausible synergy between exogenous and endogenous NPC actions, and that NPC implantation before the 6-OHDA insult can create a host microenvironment conducive to stimulation of endogenous NPCs, and protection of mature nigral neurons. PMID:19399899

  18. Effects of growth hormone on the differentiation of mouse B-lymphoid precursors.

    PubMed

    Sumita, Kiminobu; Hattori, Naoki; Inagaki, Chiyoko

    2005-03-01

    Growth hormone (GH) has been known to enhance immune responses directly or through insulin-like growth factor-I (IGF-I). The present study aimed to clarify the roles of GH in the differentiation of B-lineage precursors. In short-term bone marrow cultures, which contained stem cells and early B-lineage cells, GH (10 mug/L) treatment for one day decreased the percentages of stem cells (0.5-fold) and increased those of B-lineage cells (1.4-fold). Furthermore, GH changed the expressions of transcription factors for B cell progenitors differentiation such as paired box gene-5 (Pax-5), immunoglobulin-associated-alpha (Ig-alpha)/CD79a, Ig-beta/CD79b, and IGF-I. Thus, a physiological concentration of GH stimulated the differentiation of B-lymphoid precursors from bone marrow stem cells. Since mRNAs of both GH and GH receptor were present in stem cells and B-cell precursors in bone marrow, GH may modulate B-lymphoid precursors development in an autocrine or paracrine manner in bone marrows. PMID:15750284

  19. IMMUNOHISTOCHEMICAL CHARACTERIZATION OF THE INTRINSIC CARDIAC NEURAL PLEXUS IN WHOLE-MOUNT MOUSE HEART PREPARATIONS

    PubMed Central

    Rysevaite, Kristina; Saburkina, Inga; Pauziene, Neringa; Vaitkevicius, Raimundas; Noujaim, Sami F.; Jalife, José; Pauza, Dainius H.

    2011-01-01

    Summary BACKGROUND The intrinsic neural plexus of the mouse heart has not been adequately investigated despite the extensive use of this species in experimental cardiology. OBJECTIVE We determined the distribution of cholinergic, adrenergic and sensory neural components in whole-mount mouse heart preparations using double immunohistochemical labeling. METHODS AND RESULTS Intrinsic neurons were concentrated within 19±3 ganglia (n = 20 mice) of varying size, scattered on the medial side of the inferior caval (caudal) vein on the right atrium and close to the pulmonary veins on the left atrium. Of a total of 1082±160 neurons, most somata (83%) were choline acetyltransferase (ChAT)-immunoreactive, while 4% were tyrosine hydroxylase (TH)-immunoreactive; 14% of ganglionic cells were biphenotypic for ChAT and TH. The most intense ChAT staining was observed in axonal varicosities. ChAT was evident in nerve fibers interconnecting intrinsic ganglia. Both ChAT and TH immunoreactivity were abundant within the nerves accessing the heart. However, epicardial TH-immunoreactive nerve fibers were predominant on the dorsal and ventral left atrium, whereas most ChAT-positive axons proceeded on the heart base toward the large intrinsic ganglia and on the epicardium of the root of the right cranial vein. Substance P-positive and calcitonin gene-related peptide-immunoreactive nerve fibers were abundant on the epicardium and within ganglia adjacent to the heart hilum. Small intensely fluorescent cells were grouped into clusters of 3–8 and dispersed within large ganglia or separately on the atrial and ventricular walls. CONCLUSIONS While some nerves and neuronal bundles of the mouse epicardial plexus are mixed, most express either adrenergic or cholinergic markers. Therefore, selective stimulation and/or ablation of the functionally distinct intrinsic neural pathways should allow the study of specific effects on cardiac function. PMID:21232628

  20. Fgf8-Related Secondary Organizers Exert Different Polarizing Planar Instructions along the Mouse Anterior Neural Tube

    PubMed Central

    Crespo-Enriquez, Ivan; Partanen, Juha; Martinez, Salvador; Echevarria, Diego

    2012-01-01

    Early brain patterning depends on proper arrangement of positional information. This information is given by gradients of secreted signaling molecules (morphogens) detected by individual cells within the responding tissue, leading to specific fate decisions. Here we report that the morphogen FGF8 exerts initially a differential signal activity along the E9.5 mouse neural tube. We demonstrate that this polarizing activity codes by RAS-regulated ERK1/2 signaling and depends on the topographical location of the secondary organizers: the isthmic organizer (IsO) and the anterior neural ridge (anr) but not on zona limitans intrathalamica (zli). Our results suggest that Sprouty2, a negative modulator of RAS/ERK pathway, is important for regulating Fgf8 morphogenetic signal activity by controlling Fgf8-induced signaling pathways and positional information during early brain development. PMID:22792203

  1. Mouse neuroblastoma cell based model and the effect of epileptic events on calcium oscillations and neural spikes

    NASA Astrophysics Data System (ADS)

    Kim, Suhwan; Baek, Juyeong; Jung, Unsang; Lee, Sangwon; Jung, Woonggyu; Kim, Jeehyun; Kang, Shinwon

    2013-05-01

    Recently, Mouse neuroblastoma cells are considered as an attractive model for the study of human neurological and prion diseases, and intensively used as a model system in different areas. Among those areas, differentiation of neuro2a (N2A) cells, receptor mediated ion current, and glutamate induced physiological response are actively investigated. The reason for the interest to mouse neuroblastoma N2A cells is that they have a fast growing rate than other cells in neural origin with a few another advantages. This study evaluated the calcium oscillations and neural spikes recording of mouse neuroblastoma N2A cells in an epileptic condition. Based on our observation of neural spikes in mouse N2A cell with our proposed imaging modality, we report that mouse neuroblastoma N2A cells can be an important model related to epileptic activity studies. It is concluded that the mouse neuroblastoma N2A cells produce the epileptic spikes in vitro in the same way as produced by the neurons or the astrocytes. This evidence advocates the increased and strong level of neurotransmitters release by enhancement in free calcium using the 4-aminopyridine which causes the mouse neuroblastoma N2A cells to produce the epileptic spikes and calcium oscillation.

  2. Long-term, stable differentiation of human embryonic stem cell-derived neural precursors grafted into the adult mammalian neostriatum.

    PubMed

    Nasonkin, Igor; Mahairaki, Vasiliki; Xu, Leyan; Hatfield, Glen; Cummings, Brian J; Eberhart, Charles; Ryugo, David K; Maric, Dragan; Bar, Eli; Koliatsos, Vassilis E

    2009-10-01

    Stem cell grafts have been advocated as experimental treatments for neurological diseases by virtue of their ability to offer trophic support for injured neurons and, theoretically, to replace dead neurons. Human embryonic stem cells (HESCs) are a rich source of neural precursors (NPs) for grafting, but have been questioned for their tendency to form tumors. Here we studied the ability of HESC-derived NP grafts optimized for cell number and differentiation stage prior to transplantation, to survive and stably differentiate and integrate in the basal forebrain (neostriatum) of young adult nude rats over long periods of time (6 months). NPs were derived from adherent monolayer cultures of HESCs exposed to noggin. After transplantation, NPs showed a drastic reduction in mitotic activity and an avid differentiation into neurons that projected via major white matter tracts to a variety of forebrain targets. A third of NP-derived neurons expressed the basal forebrain-neostriatal marker dopamine-regulated and cyclic AMP-regulated phosphoprotein. Graft-derived neurons formed mature synapses with host postsynaptic structures, including dendrite shafts and spines. NPs inoculated in white matter tracts showed a tendency toward glial (primarily astrocytic) differentiation, whereas NPs inoculated in the ventricular epithelium persisted as nestin(+) precursors. Our findings demonstrate the long-term ability of noggin-derived human NPs to structurally integrate tumor-free into the mature mammalian forebrain, while maintaining some cell fate plasticity that is strongly influenced by particular central nervous system (CNS) niches. PMID:19609935

  3. Long-Term, Stable Differentiation Of Human Embryonic Stem Cell-Derived Neural Precursors Grafted Into The Adult Mammalian Neostriatum

    PubMed Central

    Nasonkin, I.; Mahairaki, V.; Xu, L.; Hatfield, G.; Cummings, B.J.; Eberhart, C.; Ryugo, D.; Maric, D.; Bar, E.; Koliatsos, V.E.

    2010-01-01

    Stem-cell grafts have been advocated as experimental treatments for neurological diseases by virtue of their ability to offer trophic support for injured neurons and, theoretically, to replace dead neurons. Human embryonic stem cells (HESCs) are a rich source of neural precursors (NPs) for grafting, but have been questioned for their tendency to form tumors. Here we studied the ability of HESC-derived NP grafts optimized for cell number and differentiation stage prior to transplantation, to survive and stably differentiate and integrate in the basal forebrain (neostriatum) of young adult nude rats over long periods of time (6 months). NPs were derived from adherent monolayer cultures of HESCs exposed to noggin. After transplantation, NPs showed a drastic reduction in mitotic activity and an avid differentiation into neurons that projected via major white matter tracts to a variety of forebrain targets. A third of NP-derived neurons expressed the basal forebrain-neostriatal marker Dopamine- and cyclic AMP-Regulated Phosphoprotein. Graft-derived neurons formed mature synapses with host post-synaptic structures, including dendrite shafts and spines. NPs inoculated in white matter tracts showed a tendency towards glial (primarily astrocytic) differentiation, whereas NPs inoculated in the ventricular epithelium persisted as nestin (+) precursors. Our findings demonstrate the long-term ability of noggin-derived human NPs to structurally integrate tumor-free into the mature mammalian forebrain, while maintaining some cell fate plasticity that is strongly influenced by particular CNS niches. PMID:19609935

  4. METHYLMERCURY INDUCED TOXICOGENOMIC RESPONSE IN C57 AND SWV MOUSE EMBRYOS UNDERGOING NEURAL TUBE CLOSURE

    PubMed Central

    Robinson, Joshua F.; Griffith, William C.; Yu, Xiaozhong; Hong, Sungwoo; Kim, Euvin; Faustman, Elaine M.

    2010-01-01

    Methylmercury (MeHg) is a developmental neurotoxicant and teratogen and is hypothesized to perturb a wide range of biological processes, like other metals including arsenic (As) and cadmium (Cd). Common inbred mouse strains including C57 (sensitive) and SWV (resistant) display differences in sensitivity to metals such as As and Cd when exposed during neurulation. In this study, we investigated the impact of MeHg on neurulation, assessing for potential differences in sensitivity and associated toxicogenomic response in C57 and SWV mouse embryos. Parallel with morphological assessments of neural tube closure, we evaluated quantitative differences in MeHg-induced alterations in expression between strains at the gene level and within gene-enriched biological processes. Specifically, we observed differing sensitivities to MeHg-induced impacts on neural tube closure between C57 and SWV embryos in a time-dependent manner. These observations correlated with greater impact on the expression of genes associated with development and environmental stress-related pathways in the C57 compared to the SWV. Additional developmental parameters (e.g. mortality, growth effects) evaluated showed mixed significant effects across the two strains and did not support observations of differential sensitivity to MeHg. This study provides potential insights into MeHg-induced mechanisms of developmental toxicity, alterations associated with increased MeHg sensitivity and common biological processes affected by metals in embryos undergoing neurulation. PMID:20493249

  5. Stabilized β-Catenin Functions through TCF/LEF Proteins and the Notch/RBP-Jκ Complex To Promote Proliferation and Suppress Differentiation of Neural Precursor Cells▿

    PubMed Central

    Shimizu, Takeshi; Kagawa, Tetsushi; Inoue, Toshihiro; Nonaka, Aya; Takada, Shinji; Aburatani, Hiroyuki; Taga, Tetsuya

    2008-01-01

    The proliferation and differentiation of neural precursor cells are mutually exclusive during brain development. Despite its importance for precursor cell self renewal, the molecular linkage between these two events has remained unclear. Fibroblast growth factor 2 (FGF2) promotes neural precursor cell proliferation and concurrently inhibits their differentiation, suggesting a cross talk between proliferation and differentiation signaling pathways downstream of the FGF receptor. We demonstrate that FGF2 signaling through phosphatidylinositol 3 kinase activation inactivates glycogen synthase kinase 3β (GSK3β) and leads to the accumulation of β-catenin in a manner different from that in the Wnt canonical pathway. The nuclear accumulated β-catenin leads to cell proliferation by activating LEF/TCF transcription factors and concurrently inhibits neuronal differentiation by potentiating the Notch1-RBP-Jκ signaling pathway. β-Catenin and the Notch1 intracellular domain form a molecular complex with the promoter region of the antineurogenic hes1 gene, allowing its expression. This signaling interplay is especially essential for neural stem cell maintenance, since the misexpression of dominant-active GSK3β completely inhibits the self renewal of neurosphere-forming stem cells and prompts their neuronal differentiation. Thus, the GSK3β/β-catenin signaling axis regulated by FGF and Wnt signals plays a pivotal role in the maintenance of neural stem/precursor cells by linking the cell proliferation to the inhibition of differentiation. PMID:18852283

  6. Depression by relaxin of neurally induced contractile responses in the mouse gastric fundus.

    PubMed

    Baccari, Maria Caterina; Nistri, Silvia; Quattrone, Silvia; Bigazzi, Mario; Bani Sacchi, Tatiana; Calamai, Franco; Bani, Daniele

    2004-01-01

    The peptide hormone relaxin, which attains high circulating levels during pregnancy, has been shown to depress small-bowel motility through a nitric oxide (NO)-mediated mechanism. In the present study we investigated whether relaxin also influences gastric contractile responses in mice. Female mice in proestrus or estrus were treated for 18 h with relaxin (1 microg s.c.) or vehicle (controls). Mechanical responses of gastric fundal strips were recorded via force-displacement transducers. Evaluation of the expression of nitric oxide synthase (NOS) isoforms was performed by immunohistochemistry and Western blot. In control mice, neurally induced contractile responses elicited by electrical field stimulation (EFS) were reduced in amplitude by addition of relaxin to the organ bath medium. In the presence of the NO synthesis inhibitor l-NNA, relaxin was ineffective. Direct smooth muscle contractile responses were not influenced by relaxin or l-NNA. In strips from relaxin-pretreated mice, the amplitude of neurally induced contractile responses was also reduced in respect to the controls, while that of direct smooth muscle contractions was not. Further addition of relaxin to the bath medium did not influence EFS-induced responses, whereas l-NNA did. An increased expression of NOS I and NOS III was observed in gastric tissues from relaxin-pretreated mice. In conclusion, the peptide hormone relaxin depresses cholinergic contractile responses in the mouse gastric fundus by up-regulating NO biosynthesis at the neural level. PMID:14522837

  7. Progranulin promotes the retinal precursor cell proliferation and the photoreceptor differentiation in the mouse retina

    PubMed Central

    Kuse, Yoshiki; Tsuruma, Kazuhiro; Sugitani, Sou; Izawa, Hiroshi; Ohno, Yuta; Shimazawa, Masamitsu; Hara, Hideaki

    2016-01-01

    Progranulin (PGRN) is a secreted growth factor associated with embryo development, tissue repair, and inflammation. In a previous study, we showed that adipose-derived stem cell-conditioned medium (ASC-CM) is rich in PGRN. In the present study, we investigated whether PGRN is associated with retinal regeneration in the mammalian retina. We evaluated the effect of ASC-CM using the N-methyl-N-nitrosourea-induced retinal damage model in mice. ASC-CM promoted the differentiation of photoreceptor cells following retinal damage. PGRN increased the number of BrdU+ cells in the outer nuclear layer following retinal damage some of which were Rx (retinal precursor cell marker) positive. PGRN also increased the number of rhodopsin+ photoreceptor cells in primary retinal cell cultures. SU11274, a hepatocyte growth factor (HGF) receptor inhibitor, attenuated the increase. These findings suggest that PGRN may affect the differentiation of retinal precursor cells to photoreceptor cells through the HGF receptor signaling pathway. PMID:27030285

  8. A post-transcriptional mechanism pacing expression of neural genes with precursor cell differentiation status

    PubMed Central

    Dai, Weijun; Li, Wencheng; Hoque, Mainul; Li, Zhuyun; Tian, Bin; Makeyev, Eugene V.

    2015-01-01

    Nervous system (NS) development relies on coherent upregulation of extensive sets of genes in a precise spatiotemporal manner. How such transcriptome-wide effects are orchestrated at the molecular level remains an open question. Here we show that 3′-untranslated regions (3′ UTRs) of multiple neural transcripts contain AU-rich cis-elements (AREs) recognized by tristetraprolin (TTP/Zfp36), an RNA-binding protein previously implicated in regulation of mRNA stability. We further demonstrate that the efficiency of ARE-dependent mRNA degradation declines in the neural lineage because of a decrease in the TTP protein expression mediated by the NS-enriched microRNA miR-9. Importantly, TTP downregulation in this context is essential for proper neuronal differentiation. On the other hand, inactivation of TTP in non-neuronal cells leads to dramatic upregulation of multiple NS-specific genes. We conclude that the newly identified miR-9/TTP circuitry limits unscheduled accumulation of neuronal mRNAs in non-neuronal cells and ensures coordinated upregulation of these transcripts in neurons. PMID:26144867

  9. The effect of interferon-{beta} on mouse neural progenitor cell survival and differentiation

    SciTech Connect

    Hirsch, Marek; Knight, Julia; Tobita, Mari; Soltys, John; Panitch, Hillel; Mao-Draayer, Yang

    2009-10-16

    Interferon-{beta} (IFN-{beta}) is a mainstay therapy for relapse-remitting multiple sclerosis (MS). However, the direct effects of IFN-{beta} on the central nervous system (CNS) are not well understood. To determine whether IFN-{beta} has direct neuroprotective effects on CNS cells, we treated adult mouse neural progenitor cells (NPCs) in vitro with IFN-{beta} and examined the effects on proliferation, apoptosis, and differentiation. We found that mouse NPCs express high levels of IFN{alpha}/{beta} receptor (IFNAR). In response to IFN-{beta} treatment, no effect was observed on differentiation or proliferation. However, IFN-{beta} treated mouse NPCs demonstrated decreased apoptosis upon growth factor withdrawal. Pathway-specific polymerase chain reaction (PCR) arrays demonstrated that IFN-{beta} treatment upregulated the STAT 1 and 2 signaling pathway, as well as GFRA2, NOD1, Caspases 1 and 12, and TNFSF10. These results suggest that IFN-{beta} can directly affect NPC survival, possibly playing a neuroprotective role in the CNS by modulating neurotrophic factors.

  10. Remyelination Is Correlated with Regulatory T Cell Induction Following Human Embryoid Body-Derived Neural Precursor Cell Transplantation in a Viral Model of Multiple Sclerosis.

    PubMed

    Plaisted, Warren C; Zavala, Angel; Hingco, Edna; Tran, Ha; Coleman, Ronald; Lane, Thomas E; Loring, Jeanne F; Walsh, Craig M

    2016-01-01

    We have recently described sustained clinical recovery associated with dampened neuroinflammation and remyelination following transplantation of neural precursor cells (NPCs) derived from human embryonic stem cells (hESCs) in a viral model of the human demyelinating disease multiple sclerosis. The hNPCs used in that study were derived by a novel direct differentiation method (direct differentiation, DD-NPCs) that resulted in a unique gene expression pattern when compared to hNPCs derived by conventional methods. Since the therapeutic potential of human NPCs may differ greatly depending on the method of derivation and culture, we wanted to determine whether NPCs differentiated using conventional methods would be similarly effective in improving clinical outcome under neuroinflammatory demyelinating conditions. For the current study, we utilized hNPCs differentiated from a human induced pluripotent cell line via an embryoid body intermediate stage (EB-NPCs). Intraspinal transplantation of EB-NPCs into mice infected with the neurotropic JHM strain of mouse hepatitis virus (JHMV) resulted in decreased accumulation of CD4+ T cells in the central nervous system that was concomitant with reduced demyelination at the site of injection. Dampened neuroinflammation and remyelination was correlated with a transient increase in CD4+FOXP3+ regulatory T cells (Tregs) concentrated within the peripheral lymphatics. However, compared to our earlier study, pathological improvements were modest and did not result in significant clinical recovery. We conclude that the genetic signature of NPCs is critical to their effectiveness in this model of viral-induced neurologic disease. These comparisons will be useful for understanding what factors are critical for the sustained clinical improvement. PMID:27310015

  11. Remyelination Is Correlated with Regulatory T Cell Induction Following Human Embryoid Body-Derived Neural Precursor Cell Transplantation in a Viral Model of Multiple Sclerosis

    PubMed Central

    Plaisted, Warren C.; Zavala, Angel; Hingco, Edna; Tran, Ha; Coleman, Ronald; Lane, Thomas E.; Loring, Jeanne F.; Walsh, Craig M.

    2016-01-01

    We have recently described sustained clinical recovery associated with dampened neuroinflammation and remyelination following transplantation of neural precursor cells (NPCs) derived from human embryonic stem cells (hESCs) in a viral model of the human demyelinating disease multiple sclerosis. The hNPCs used in that study were derived by a novel direct differentiation method (direct differentiation, DD-NPCs) that resulted in a unique gene expression pattern when compared to hNPCs derived by conventional methods. Since the therapeutic potential of human NPCs may differ greatly depending on the method of derivation and culture, we wanted to determine whether NPCs differentiated using conventional methods would be similarly effective in improving clinical outcome under neuroinflammatory demyelinating conditions. For the current study, we utilized hNPCs differentiated from a human induced pluripotent cell line via an embryoid body intermediate stage (EB-NPCs). Intraspinal transplantation of EB-NPCs into mice infected with the neurotropic JHM strain of mouse hepatitis virus (JHMV) resulted in decreased accumulation of CD4+ T cells in the central nervous system that was concomitant with reduced demyelination at the site of injection. Dampened neuroinflammation and remyelination was correlated with a transient increase in CD4+FOXP3+ regulatory T cells (Tregs) concentrated within the peripheral lymphatics. However, compared to our earlier study, pathological improvements were modest and did not result in significant clinical recovery. We conclude that the genetic signature of NPCs is critical to their effectiveness in this model of viral-induced neurologic disease. These comparisons will be useful for understanding what factors are critical for the sustained clinical improvement. PMID:27310015

  12. Adult neural precursor cells form connexin-dependent networks that improve their survival.

    PubMed

    Ravella, Ajaya; Ringstedt, Thomas; Brion, Jean-Pierre; Pandolfo, Massimo; Herlenius, Eric

    2015-10-21

    Establishment of cellular networks and calcium homeostasis are essential for embryonic stem cell proliferation and differentiation. We also hypothesized that adult neural progenitor cells form functional cellular networks relevant for their development. We isolated neuronal progenitor cells from the subventricular zone of 5-week-old mice to investigate the role of gap junctions, calcium homeostasis, and cellular networks in cell differentiation and survival. Western blotting and reverse transcription-PCR showed that the cells expressed the gap junction components connexin 26, 36, 43, and 45, and that expression of connexin 43 increased in early (8 days) differentiated cells. Transmission electron microscopy and immunocytochemistry also indicated that gap junctions were present. Scrape-loading experiments showed dye transfer between cells that could be prevented by gapjunction blockers; thus, functional intercellular gap junctions had been established. However, dye transfer was four times stronger in differentiated cultures, correlating with the increased connexin 43 expression. During time-lapse calcium imaging, both differentiated and undifferentiated cultures showed spontaneous calcium activity that was reduced by gap junction blockers. Cross-correlation analysis of the calcium recordings showed that the cells were interconnected through gap junctions and that the early-differentiated cells were organized in small-world networks. Gap junction blockers did not affect proliferation and differentiation, but resulted in twice as many apoptotic cells. mRNAi knockdown of connexin 43 also doubled the number of apoptotic cells. We conclude that adult neural progenitor cells form networks in vitro that are strengthened during early differentiation by increased expression of connexin 43. The networks are functional and improve cell survival. PMID:26351758

  13. PSA-NCAM(+) neural precursor cells from human embryonic stem cells promote neural tissue integrity and behavioral performance in a rat stroke model.

    PubMed

    Kim, Han-Soo; Choi, Seong-Mi; Yang, Wonsuk; Kim, Dae-Sung; Lee, Dongjin R; Cho, Sung-Rae; Kim, Dong-Wook

    2014-12-01

    Recently, cell-based therapy has been highlighted as an alternative to treating ischemic brain damage in stroke patients. The present study addresses the therapeutic potential of polysialic acid-neural cell adhesion molecule (PSA-NCAM)-positive neural precursor cells (NPC(PSA-NCAM+)) derived from human embryonic stem cells (hESCs) in a rat stroke model with permanent middle cerebral artery occlusion. Data showed that rats transplanted with NPC(PSA-NCAM+) are superior to those treated with phosphate buffered saline (PBS) or mesenchymal stem cells (MSCs) in behavioral performance throughout time points. In order to investigate its underlying events, immunohistochemical analysis was performed on rat ischemic brains treated with PBS, MSCs, and NPC(PSA-NCAM+). Unlike MSCs, NPC(PSA-NCAM+) demonstrated a potent immunoreactivity against human specific nuclei, doublecortin, and Tuj1 at day 26 post-transplantation, implying their survival, differentiation, and integration in the host brain. Significantly, NPC(PSA-NCAM+) evidently lowered the positivity of microglial ED-1 and astrocytic GFAP, suggesting a suppression of adverse glial activation in the host brain. In addition, NPC(PSA-NCAM+) elevated α-SMA(+) immunoreactivity and the expression of angiopoietin-1 indicating angiogenic stimulation in the host brain. Taken together, the current data demonstrate that transplanted NPC(PSA-NCAM+) preserve brain tissue with reduced infarct size and improve behavioral performance through actions encompassing anti-reactive glial activation and pro-angiogenic activity in a rat stroke model. In conclusion, the present findings support the potentiality of NPC(PSA-NCAM+) as the promising source in the development of cell-based therapy for neurological diseases including ischemic stroke. PMID:24974101

  14. Rhomboid Enhancer Activity Defines a Subset of Drosophila Neural Precursors Required for Proper Feeding, Growth and Viability

    PubMed Central

    Gresser, Amy L.; Gutzwiller, Lisa M.; Gauck, Mackenzie K.; Hartenstein, Volker; Cook, Tiffany A.; Gebelein, Brian

    2015-01-01

    Organismal growth regulation requires the interaction of multiple metabolic, hormonal and neuronal pathways. While the molecular basis for many of these are well characterized, less is known about the developmental origins of growth regulatory structures and the mechanisms governing control of feeding and satiety. For these reasons, new tools and approaches are needed to link the specification and maturation of discrete cell populations with their subsequent regulatory roles. In this study, we characterize a rhomboid enhancer element that selectively labels four Drosophila embryonic neural precursors. These precursors give rise to the hypopharyngeal sensory organ of the peripheral nervous system and a subset of neurons in the deutocerebral region of the embryonic central nervous system. Post embryogenesis, the rhomboid enhancer is active in a subset of cells within the larval pharyngeal epithelium. Enhancer-targeted toxin expression alters the morphology of the sense organ and results in impaired larval growth, developmental delay, defective anterior spiracle eversion and lethality. Limiting the duration of toxin expression reveals differences in the critical periods for these effects. Embryonic expression causes developmental defects and partially penetrant pre-pupal lethality. Survivors of embryonic expression, however, ultimately become viable adults. In contrast, post-embryonic toxin expression results in fully penetrant lethality. To better define the larval growth defect, we used a variety of assays to demonstrate that toxin-targeted larvae are capable of locating, ingesting and clearing food and they exhibit normal food search behaviors. Strikingly, however, following food exposure these larvae show a rapid decrease in consumption suggesting a satiety-like phenomenon that correlates with the period of impaired larval growth. Together, these data suggest a critical role for these enhancer-defined lineages in regulating feeding, growth and viability. PMID

  15. Rhomboid Enhancer Activity Defines a Subset of Drosophila Neural Precursors Required for Proper Feeding, Growth and Viability.

    PubMed

    Gresser, Amy L; Gutzwiller, Lisa M; Gauck, Mackenzie K; Hartenstein, Volker; Cook, Tiffany A; Gebelein, Brian

    2015-01-01

    Organismal growth regulation requires the interaction of multiple metabolic, hormonal and neuronal pathways. While the molecular basis for many of these are well characterized, less is known about the developmental origins of growth regulatory structures and the mechanisms governing control of feeding and satiety. For these reasons, new tools and approaches are needed to link the specification and maturation of discrete cell populations with their subsequent regulatory roles. In this study, we characterize a rhomboid enhancer element that selectively labels four Drosophila embryonic neural precursors. These precursors give rise to the hypopharyngeal sensory organ of the peripheral nervous system and a subset of neurons in the deutocerebral region of the embryonic central nervous system. Post embryogenesis, the rhomboid enhancer is active in a subset of cells within the larval pharyngeal epithelium. Enhancer-targeted toxin expression alters the morphology of the sense organ and results in impaired larval growth, developmental delay, defective anterior spiracle eversion and lethality. Limiting the duration of toxin expression reveals differences in the critical periods for these effects. Embryonic expression causes developmental defects and partially penetrant pre-pupal lethality. Survivors of embryonic expression, however, ultimately become viable adults. In contrast, post-embryonic toxin expression results in fully penetrant lethality. To better define the larval growth defect, we used a variety of assays to demonstrate that toxin-targeted larvae are capable of locating, ingesting and clearing food and they exhibit normal food search behaviors. Strikingly, however, following food exposure these larvae show a rapid decrease in consumption suggesting a satiety-like phenomenon that correlates with the period of impaired larval growth. Together, these data suggest a critical role for these enhancer-defined lineages in regulating feeding, growth and viability. PMID

  16. Mouse neuroblastoma cell-based model and the effect of epileptic events on calcium oscillations and neural spikes

    NASA Astrophysics Data System (ADS)

    Kim, Suhwan; Jung, Unsang; Baek, Juyoung; Lee, Sangwon; Jung, Woonggyu; Kim, Jeehyun; Kang, Shinwon

    2013-01-01

    Recently, mouse neuroblastoma cells have been considered as an attractive model for the study of human neurological and prion diseases, and they have been intensively used as a model system in different areas. For example, the differentiation of neuro2a (N2A) cells, receptor-mediated ion current, and glutamate-induced physiological responses have been actively investigated with these cells. These mouse neuroblastoma N2A cells are of interest because they grow faster than other cells of neural origin and have a number of other advantages. The calcium oscillations and neural spikes of mouse neuroblastoma N2A cells in epileptic conditions are evaluated. Based on our observations of neural spikes in these cells with our proposed imaging modality, we reported that they can be an important model in epileptic activity studies. We concluded that mouse neuroblastoma N2A cells produce epileptic spikes in vitro in the same way as those produced by neurons or astrocytes. This evidence suggests that increased levels of neurotransmitter release due to the enhancement of free calcium from 4-aminopyridine causes the mouse neuroblastoma N2A cells to produce epileptic spikes and calcium oscillations.

  17. Nanofiber Matrices Promote the Neuronal Differentiation of Human Embryonic Stem Cell-Derived Neural Precursors In Vitro

    PubMed Central

    Lim, Shawn H.; Christopherson, Gregory T.; Xu, Leyan; Nasonkin, Igor; Yu, Christopher; Mao, Hai-Quan; Koliatsos, Vassilis E.

    2011-01-01

    The potential of human embryonic stem (ES) cells as experimental therapies for neuronal replacement has recently received considerable attention. In view of the organization of the mature nervous system into distinct neural circuits, key challenges of such therapies are the directed differentiation of human ES cell-derived neural precursors (NPs) into specific neuronal types and the directional growth of axons along specified trajectories. In the present study, we cultured human NPs derived from the NIH-approved ES line BGO1 on polycaprolactone fiber matrices of different diameter (i.e., nanofibers and microfibers) and orientation (i.e., aligned and random); fibers were coated with poly-L-ornithine/laminin to mimic the extracellular matrix and support the adhesion, viability, and differentiation of NPs. On aligned fibrous meshes, human NPs adopt polarized cell morphology with processes extending along the axis of the fiber, whereas NPs on plain tissue culture surfaces or random fiber substrates form nonpolarized neurite networks. Under differentiation conditions, human NPs cultured on aligned fibrous substrates show a higher rate of neuronal differentiation than other matrices; 62% and 86% of NPs become TUJ1 (+) early neurons on aligned micro- and nanofibers, respectively, whereas only 32% and 27% of NPs acquire the same fate on random micro- and nanofibers. Metabolic cell activity/viability studies reveal that fiber alignment and diameter also have an effect on NP viability, but only in the presence of mitogens. Our findings demonstrate that fibrous substrates serve as an artificial extracellular matrix and provide a microenviroment that influences key aspects of the neuronal differentiation of ES-derived NPs. PMID:20973749

  18. Nanofiber matrices promote the neuronal differentiation of human embryonic stem cell-derived neural precursors in vitro.

    PubMed

    Mahairaki, Vasiliki; Lim, Shawn H; Christopherson, Gregory T; Xu, Leyan; Nasonkin, Igor; Yu, Christopher; Mao, Hai-Quan; Koliatsos, Vassilis E

    2011-03-01

    The potential of human embryonic stem (ES) cells as experimental therapies for neuronal replacement has recently received considerable attention. In view of the organization of the mature nervous system into distinct neural circuits, key challenges of such therapies are the directed differentiation of human ES cell-derived neural precursors (NPs) into specific neuronal types and the directional growth of axons along specified trajectories. In the present study, we cultured human NPs derived from the NIH-approved ES line BGO1 on polycaprolactone fiber matrices of different diameter (i.e., nanofibers and microfibers) and orientation (i.e., aligned and random); fibers were coated with poly-L-ornithine/laminin to mimic the extracellular matrix and support the adhesion, viability, and differentiation of NPs. On aligned fibrous meshes, human NPs adopt polarized cell morphology with processes extending along the axis of the fiber, whereas NPs on plain tissue culture surfaces or random fiber substrates form nonpolarized neurite networks. Under differentiation conditions, human NPs cultured on aligned fibrous substrates show a higher rate of neuronal differentiation than other matrices; 62% and 86% of NPs become TUJ1 (+) early neurons on aligned micro- and nanofibers, respectively, whereas only 32% and 27% of NPs acquire the same fate on random micro- and nanofibers. Metabolic cell activity/viability studies reveal that fiber alignment and diameter also have an effect on NP viability, but only in the presence of mitogens. Our findings demonstrate that fibrous substrates serve as an artificial extracellular matrix and provide a microenviroment that influences key aspects of the neuronal differentiation of ES-derived NPs. PMID:20973749

  19. Chondroitinase and growth factors enhance activation and oligodendrocyte differentiation of endogenous neural precursor cells after spinal cord injury.

    PubMed

    Karimi-Abdolrezaee, Soheila; Schut, Desiree; Wang, Jian; Fehlings, Michael G

    2012-01-01

    The adult spinal cord harbours a population of multipotent neural precursor cells (NPCs) with the ability to replace oligodendrocytes. However, despite this capacity, proliferation and endogenous remyelination is severely limited after spinal cord injury (SCI). In the post-traumatic microenvironment following SCI, endogenous spinal NPCs mainly differentiate into astrocytes which could contribute to astrogliosis that exacerbate the outcomes of SCI. These findings emphasize a key role for the post-SCI niche in modulating the behaviour of spinal NPCs after SCI. We recently reported that chondroitin sulphate proteoglycans (CSPGs) in the glial scar restrict the outcomes of NPC transplantation in SCI by reducing the survival, migration and integration of engrafted NPCs within the injured spinal cord. These inhibitory effects were attenuated by administration of chondroitinase (ChABC) prior to NPC transplantation. Here, in a rat model of compressive SCI, we show that perturbing CSPGs by ChABC in combination with sustained infusion of growth factors (EGF, bFGF and PDGF-AA) optimize the activation and oligodendroglial differentiation of spinal NPCs after injury. Four days following SCI, we intrathecally delivered ChABC and/or GFs for seven days. We performed BrdU incorporation to label proliferating cells during the treatment period after SCI. This strategy increased the proliferation of spinal NPCs, reduced the generation of new astrocytes and promoted their differentiation along an oligodendroglial lineage, a prerequisite for remyelination. Furthermore, ChABC and GF treatments enhanced the response of non-neural cells by increasing the generation of new vascular endothelial cells and decreasing the number of proliferating macrophages/microglia after SCI. In conclusions, our data strongly suggest that optimization of the behaviour of endogenous spinal NPCs after SCI is critical not only to promote endogenous oligodendrocyte replacement, but also to reverse the otherwise

  20. Influence of MHC on thymus repopulation following intrathymic transfer of mouse T-cell precursors

    SciTech Connect

    Chervenak, R.; Altazan, J.D.

    1987-04-01

    T-cell precursors (pre-T cells) traditionally have been detected by their ability to repopulate the thymus of heavily irradiated mice following intravenous injection. Recently, an assay system involving the direct injection of pre-T cells into the thymus of sublethally irradiated animals has been described. Here we report the results of experiments designed to evaluate the ability of bone marrow cells to produce thymic repopulation following intrathymic injection in a wide range of donor-host strain combinations. Irradiated (600 R) mice were injected intrathymically with 2 X 10(6) bone marrow cells which differed from the recipient with respect to their Thy-1 allotype and the percentage of thymus cells expressing either donor- or recipient-type Thy-1 was determined 9 to 23 days after injection. The results of these experiments showed that thymocytes expressing the Thy-1 allotype derived from the donor marrow were only detected when the donor and host were matched at MHC. By contrast, thymic repopulation by MHC-mismatched donor marrow cells could readily be observed when these cells were given intravenously.

  1. Identification of myocardial and vascular precursor cells in human and mouse epicardium.

    PubMed

    Limana, Federica; Zacheo, Antonella; Mocini, David; Mangoni, Antonella; Borsellino, Giovanna; Diamantini, Adamo; De Mori, Roberta; Battistini, Luca; Vigna, Elisa; Santini, Massimo; Loiaconi, Vincenzo; Pompilio, Giulio; Germani, Antonia; Capogrossi, Maurizio C

    2007-12-01

    During cardiac development, the epicardium is the source of multipotent mesenchymal cells, which give rise to endothelial and smooth muscle cells in coronary vessels and also, possibly, to cardiomyocytes. The aim of the present study was to determine whether stem cells are retained in the adult human and murine epicardium and to investigate the regenerative potential of these cells following acute myocardial infarction. We show that c-kit(+) and CD34(+) cells can indeed be detected in human fetal and adult epicardium and that they represent 2 distinct populations. Both subsets of cells were negative for CD45, a cell surface marker that identifies the hematopoietic cell lineage. Immunofluorescence revealed that freshly isolated c-kit(+) and CD34(+) cells expressed early and late cardiac transcription factors and could acquire an endothelial phenotype in vitro. In the murine model of myocardial infarction, there was an increase in the absolute number and proliferation of epicardial c-kit(+) cells 3 days after coronary ligation; at this time point, epicardial c-kit(+) cells were identified in the subepicardial space and expressed GATA4. Furthermore, 1 week after myocardial infarction, cells coexpressing c-kit(+), together with endothelial or smooth muscle cell markers, were identified in the wall of subepicardial blood vessels. In summary, the postnatal epicardium contains a cell population with stem cell characteristics that retains the ability to give rise to myocardial precursors and vascular cells. These cells may play a role in the regenerative response to cardiac damage. PMID:17947800

  2. SOX2 primes the epigenetic landscape in neural precursors enabling proper gene activation during hippocampal neurogenesis

    PubMed Central

    Amador-Arjona, Alejandro; Cimadamore, Flavio; Huang, Chun-Teng; Wright, Rebecca; Lewis, Susan; Gage, Fred H.; Terskikh, Alexey V.

    2015-01-01

    Newborn granule neurons generated from neural progenitor cells (NPCs) in the adult hippocampus play a key role in spatial learning and pattern separation. However, the molecular mechanisms that control activation of their neurogenic program remain poorly understood. Here, we report a novel function for the pluripotency factor sex-determining region Y (SRY)-related HMG box 2 (SOX2) in regulating the epigenetic landscape of poised genes activated at the onset of neuronal differentiation. We found that SOX2 binds to bivalently marked promoters of poised proneural genes [neurogenin 2 (Ngn2) and neurogenic differentiation 1 (NeuroD1)] and a subset of neurogenic genes [e.g., SRY-box 21 (Sox21), brain-derived neurotrophic factor (Bdnf), and growth arrest and DNA-damage–inducible, beta (Gadd45b)] where it functions to maintain the bivalent chromatin state by preventing excessive polycomb repressive complex 2 activity. Conditional ablation of SOX2 in adult hippocampal NPCs impaired the activation of proneural and neurogenic genes, resulting in increased neuroblast death and functionally aberrant newborn neurons. We propose that SOX2 sets a permissive epigenetic state in NPCs, thus enabling proper activation of the neuronal differentiation program under neurogenic cue. PMID:25825708

  3. Neural stem/progenitor cell properties of glial cells in the adult mouse auditory nerve

    PubMed Central

    Lang, Hainan; Xing, Yazhi; Brown, LaShardai N.; Samuvel, Devadoss J.; Panganiban, Clarisse H.; Havens, Luke T.; Balasubramanian, Sundaravadivel; Wegner, Michael; Krug, Edward L.; Barth, Jeremy L.

    2015-01-01

    The auditory nerve is the primary conveyor of hearing information from sensory hair cells to the brain. It has been believed that loss of the auditory nerve is irreversible in the adult mammalian ear, resulting in sensorineural hearing loss. We examined the regenerative potential of the auditory nerve in a mouse model of auditory neuropathy. Following neuronal degeneration, quiescent glial cells converted to an activated state showing a decrease in nuclear chromatin condensation, altered histone deacetylase expression and up-regulation of numerous genes associated with neurogenesis or development. Neurosphere formation assays showed that adult auditory nerves contain neural stem/progenitor cells (NSPs) that were within a Sox2-positive glial population. Production of neurospheres from auditory nerve cells was stimulated by acute neuronal injury and hypoxic conditioning. These results demonstrate that a subset of glial cells in the adult auditory nerve exhibit several characteristics of NSPs and are therefore potential targets for promoting auditory nerve regeneration. PMID:26307538

  4. Induction of neural stem cell-like cells (NSCLCs) from mouse astrocytes by Bmi1

    SciTech Connect

    Moon, Jai-Hee; Yoon, Byung Sun; Kim, Bona; Park, Gyuman; Jung, Hye-Youn; Maeng, Isaac; Jun, Eun Kyoung; Yoo, Seung Jun; Kim, Aeree; Oh, Sejong; Whang, Kwang Youn; Kim, Hyunggee; Kim, Dong-Wook; Kim, Ki Dong; You, Seungkwon

    2008-06-27

    Recently, Bmi1 was shown to control the proliferation and self-renewal of neural stem cells (NSCs). In this study, we demonstrated the induction of NSC-like cells (NSCLCs) from mouse astrocytes by Bmi1 under NSC culture conditions. These NSCLCs exhibited the morphology and growth properties of NSCs, and expressed NSC marker genes, including nestin, CD133, and Sox2. In vitro differentiation of NSCLCs resulted in differentiated cell populations containing astrocytes, neurons, and oligodendrocytes. Following treatment with histone deacetylase inhibitors (trichostatin A and valproic acid), the potential of NSCLCs for proliferation, dedifferentiation, and self-renewal was significantly inhibited. Our data indicate that multipotent NSCLCs can be generated directly from astrocytes by the addition of Bmi1.

  5. Effective detection of corrected dystrophin loci in mdx mouse myogenic precursors.

    PubMed

    Todaro, Marian; Quigley, Anita; Kita, Magdalena; Chin, Judy; Lowes, Kym; Kornberg, Andrew J; Cook, Mark J; Kapsa, Robert

    2007-08-01

    Targeted corrective gene conversion (TCGC) holds much promise as a future therapy for many hereditary diseases in humans. Mutation correction frequencies varying between 0.0001% and 40% have been reported using chimeraplasty, oligoplasty, triplex-forming oligonucleotides, and small corrective PCR amplicons (CPA). However, PCR technologies used to detect correction events risk either falsely indicating or greatly exaggerating the presence of corrected loci. This is a problem that is considerably exacerbated by attempted improvement of the TCGC system using high corrective nucleic acid (CNA) to nuclear ratios. Small fragment homologous replacement (SFHR)-mediated correction of the exon 23 dystrophin (DMD) gene mutation in the mdx mouse model of DMD has been used in this study to evaluate the effect of increasing CPA amounts. In these experiments, we detected extremely high levels of apparently corrected loci and determined that at higher CNA to nuclear ratios the extent of locus correction was highly exaggerated by residual CNA species in the nucleic acids extracted from the treated cells. This study describes a generic locus-specific detection protocol designed to eradicate residual CNA species and avoid the artifactual or exaggerated detection of gene correction. PMID:17394239

  6. Preparation of an Awake Mouse for Recording Neural Responses and Injecting Tracers

    PubMed Central

    Muniak, Michael A.; Mayko, Zachary M.; Ryugo, David K.; Portfors, Christine V.

    2012-01-01

    It is well known that anesthesia alters neural response properties in various regions of the brain.13. In the auditory system, fundamental response properties of brainstem neurons including threshold, frequency specificity, and inhibitory sidebands are altered in significant ways under anesthesia1-2. These observations prompted physiologists to seek ways to record from single neurons without the contaminating effects of anesthesia. One result was a decerebrate preparation, where the brainstem was completely transected at the level of the midbrain4. The drawbacks of this preparation are a formidable surgery, the elimination of descending projections from the forebrain, and an inability to use sensory stimulation to examine structures above the midbrain. A different strategy has been to implant electrode arrays chronically to record from single neurons and multiunit clusters while the animal is awake and/or behaving5,6. These techniques however are not compatible with injecting tracer dyes after first electrophysiologically characterizing a brain structure. To avoid altering neural response properties with anesthetics while recording electrophysiological response properties from single neurons, we have adapted a head restraint technique long used in bats7-9 to mouse10-12. Using this method, we are able to conduct electrophysiological recordings over several days in the unanesthetized mouse. At the end of the recording sessions, we can then inject a dye to reconstruct electrode positions and recording sites or inject a tracer so that pathways to and from the recording loci can be determined. This method allows for well isolated single neuron recordings over multiple days without the use anesthetics. PMID:22781848

  7. Ginkgo Biloba Extract Attenuates Oxidative Stress and Apoptosis in Mouse Cochlear Neural Stem Cells.

    PubMed

    Wang, Congpin; Wang, Bin

    2016-05-01

    In the organ or Corti, oxidative stress could result in damage to the hearing, and neural stem cells (NSCs) hold great therapeutic potential in treating hearing loss. Ginkgo biloba extract (GBE) has been widely shown to exhibit anti-oxidative and anti-apoptotic effects in treatments of neural damage and disorder. Using hydrogen peroxide to induced oxidative stress as a model, we investigated the anti-oxidative role of GBE in isolated mouse cochlear NSCs. GBE treatment was found to significantly promote viability of NSCs, by markedly attenuating hydrogen peroxide induced oxidative stress. In addition, this anti-oxidative function of GBE was also able to prevent mitochondrial depolarization and subsequent apoptosis. Moreover, the anti-apoptotic role of GBE was mediated by antagonizing the intrinsic mitochondrial apoptotic pathway, where GBE could reverse the changes in key intrinsic apoptosis pathway factors including Bcl-2, Bax, and Caspase-3. Our data provided the first report on the beneficial role of GBE in protecting cochlear NSCs, by attenuating oxidative stress triggered intrinsic apoptosis, therefore supporting the potential therapeutic value of GBE in preventing oxidative stress-related hearing loss. Copyright © 2016 John Wiley & Sons, Ltd. PMID:26799058

  8. Dnmt3a regulates both cell proliferation and differentiation of mouse neural stem cells

    PubMed Central

    Wu, Zhourui; Huang, Kevin; Yu, Juehua; Le, Thuc; Namihira, Masakasu; Liu, Yupeng; Zhang, Jun; Xue, Zhigang; Cheng, Liming; Fan, Guoping

    2012-01-01

    DNA methylation is known to regulate cell differentiation and neuronal function in vivo. Here we examined whether deficiency of a de novo DNA methyltransferase, Dnmt3a, affects in vitro differentiation of mouse embryonic stem cells (mESCs) to neuronal and glial cell lineages. Early passage neural stem cells (NSCs) derived from Dnmt3a-deficient ESCs exhibited a moderate phenotype in precocious glial differentiation compared to wild-type counterparts. However, successive passaging to passage six (P6), when wild-type NSCs become gliogenic, revealed a robust phenotype of precocious astrocyte and oligodendrocyte differentiation in Dnmt3a−/− NSCs, consistent with our previous findings in the more severely hypomethylated Dnmt1−/− NSCs. Mass-spectrometry analysis revealed total levels of methylcytosine in Dnmt3a−/− NSCs at P6 were globally hypomethylated. Moreover, Dnmt3a−/− NSC proliferation rate was significantly increased when compared to control from P6 on. Thus, our work revealed a novel role for Dnmt3a in regulating both the timing of neural cell differentiation and cell proliferation in the paradigm of mESC-derived-NSCs. PMID:22714992

  9. Effects of heat shock on survival, proliferation and differentiation of mouse neural stem cells.

    PubMed

    Omori, Hiroyuki; Otsu, Masahiro; Suzuki, Asami; Nakayama, Takashi; Akama, Kuniko; Watanabe, Masaru; Inoue, Nobuo

    2014-02-01

    Hyperthermia during pregnancy is a significant cause of reproductive problems ranging from abortion to congenital defects of the central nervous system (CNS), including neural tube defects and microcephaly. Neural stem cells (NSCs) can proliferate and differentiate into neurons and glia, playing a key role in the formation of the CNS. Here, we examined the effects of heat shock on homogeneous proliferating NSCs derived from mouse embryonic stem cells. After heat shock at 42 °C for 20 min, the proliferating NSCs continued to proliferate, although subtle changes were observed in gene expression and cell survival and proliferation. In contrast, heat shock at 43 °C caused a variety of responses: the up-regulation of genes encoding heat shock proteins (HSP), induction of apoptosis, temporal inhibition of cell proliferation and retardation of differentiation. Finally, effects of heat shock at 44 °C were severe, with almost all cells disappearing and the remaining cells losing the capacity to proliferate and differentiate. These temperature-dependent effects of heat shock on NSCs may be valuable in elucidating the mechanisms by which hyperthermia during pregnancy causes various reproductive problems. PMID:24316183

  10. Characterization of neural stem cells and their progeny in the sensory circumventricular organs of adult mouse.

    PubMed

    Furube, Eriko; Morita, Mitsuhiro; Miyata, Seiji

    2015-11-01

    Although evidence has accumulated that neurogenesis and gliogenesis occur in the subventricular zone (SVZ) and subgranular zone (SGZ) of adult mammalian brains, recent studies indicate the presence of neural stem cells (NSCs) in adult brains, particularly the circumventricular regions. In the present study, we aimed to determine characterization of NSCs and their progenitor cells in the sensory circumventricular organs (CVOs), including organum vasculosum of the lamina terminalis, subfornical organ, and area postrema of adult mouse. There were two types of NSCs: tanycyte-like ependymal cells and astrocyte-like cells. Astrocyte-like NSCs proliferated slowly and oligodendrocyte progenitor cells (OPCs) and neural progenitor cells (NPCs) actively divided. Molecular marker protein expression of NSCs and their progenitor cells were similar to those reported in the SVZ and SGZ, except that astrocyte-like NSCs expressed S100β. These circumventricular NSCs possessed the capacity to give rise to oligodendrocytes and sparse numbers of neurons and astrocytes in the sensory CVOs and adjacent brain regions. The inhibition of vascular endothelial growth factor (VEGF) signaling by using a VEGF receptor-associated tyrosine kinase inhibitor AZD2171 largely suppressed basal proliferation of OPCs. A single systemic administration of lipopolysaccharide attenuated proliferation of OPCs and induced remarkable proliferation of microglia. The present study indicates that sensory circumventricular NSCs provide new neurons and glial cells in the sensory CVOs and adjacent brain regions. PMID:25994374

  11. Pro-gliogenic effect of IL-1alpha in the differentiation of embryonic neural precursor cells in vitro.

    PubMed

    Ajmone-Cat, Maria Antonietta; Cacci, Emanuele; Ragazzoni, Ylenia; Minghetti, Luisa; Biagioni, Stefano

    2010-05-01

    Inflammation is regarded as a main obstacle to brain regeneration. Major detrimental effects are attributed to microglial/macrophagic products, such as TNF-alpha and interleukin (IL)-6. The role of cytokines of the IL-1 family, particularly of IL-1alpha, in the modulation of neural precursor cell (NPC) properties is less characterized. IL-1alpha is one of the most abundant cytokines released upon acute stimulation of microglia with lipopolysaccharide and is down-regulated upon chronic stimulation. As we recently demonstrated, acutely activated microglia reduces NPC survival, prevent neuronal differentiation and promote glial differentiation. Chronically activated microglia are instead permissive to NPC survival and neuronal differentiation, and less effective in promoting astrocytic differentiation. We thus investigated whether IL-1alpha could contribute to the effects of acutely activated microglia on NPC. We found that NPC express functional IL-1 receptors and that exposure to recombinant IL-1alpha strongly enhances NPC differentiation into astrocytes, without affecting cell viability and neuronal differentiation. In the same conditions, recombinant IL-1beta has pro-gliogenic effects at concentrations 10-fold higher than those found in activated microglial conditioned media. Interestingly, immunodepletion of IL-1alpha in activated microglial conditioned media fails to revert microglial pro-gliogenic action and slightly enhances neuronal differentiation, revealing that other microglial-derived factors contribute to the modulation of NPC properties. PMID:20236219

  12. Epac2 contributes to PACAP-induced astrocytic differentiation through calcium ion influx in neural precursor cells

    PubMed Central

    Seo, Hyunhyo; Lee, Kyungmin

    2016-01-01

    Astrocytes play a critical role in normal brain functions and maintaining the brain microenvironment, and defects in astrocytogenesis during neurodevelopment could give rise to severe mental illness and psychiatric disorders. During neuro-embryogenesis, astrocytogenesis involves astrocytic differentiation of neural precursor cells (NPCs) induced by signals from ciliary neurotrophic factor (CNTF) or pituitary adenylate cyclase-activating peptide (PACAP). However, in contrast to the CNTF signaling pathway, the exact mechanism underlying astrocytic differentiation induced by PACAP is unknown. In the present study, we aimed to verify a signaling pathway specific to PACAP-induced astrocytogenesis, using exchange protein directly activated by cAMP2 (Epac2)-knockout mice. We found that PACAP could trigger astrocytic differentiation of NPCs via Epac2 activation and an increase in the intracellular calcium concentration via a calcium ion influx. Taken together, we concluded that astrocytogenesis stimulated by PACAP occurs through a novel signaling pathway independent from CNTF-JAK/STAT signaling, that is the well-known pathway of astrocytogenesis. [BMB Reports 2016; 49(2): 128-133] PMID:26645637

  13. Epac2 contributes to PACAP-induced astrocytic differentiation through calcium ion influx in neural precursor cells.

    PubMed

    Seo, Hyunhyo; Lee, Kyungmin

    2016-02-01

    Astrocytes play a critical role in normal brain functions and maintaining the brain microenvironment, and defects in astrocytogenesis during neurodevelopment could give rise to severe mental illness and psychiatric disorders. During neuro-embryogenesis, astrocytogenesis involves astrocytic differentiation of neural precursor cells (NPCs) induced by signals from ciliary neurotrophic factor (CNTF) or pituitary adenylate cyclase-activating peptide (PACAP). However, in contrast to the CNTF signaling pathway, the exact mechanism underlying astrocytic differentiation induced by PACAP is unknown. In the present study, we aimed to verify a signaling pathway specific to PACAP-induced astrocytogenesis, using exchange protein directly activated by cAMP2 (Epac2)-knockout mice. We found that PACAP could trigger astrocytic differentiation of NPCs via Epac2 activation and an increase in the intracellular calcium concentration via a calcium ion influx. Taken together, we concluded that astrocytogenesis stimulated by PACAP occurs through a novel signaling pathway independent from CNTF-JAK/STAT signaling, that is the well-known pathway of astrocytogenesis. [BMB Reports 2016; 49(2): 128-133]. PMID:26645637

  14. Decreased demand for olfactory periglomerular cells impacts on neural precursor cell viability in the rostral migratory stream.

    PubMed

    Langenfurth, Anika; Gu, Song; Bautze, Verena; Zhang, Caiyi; Neumann, Julia E; Schüller, Ulrich; Stock, Kristin; Wolf, Susanne A; Maier, Anna-Maria; Mastrella, Giorgia; Pak, Andrew; Cheng, Hongwei; Kälin, Roland E; Holmbeck, Kenn; Strotmann, Jörg; Kettenmann, Helmut; Glass, Rainer

    2016-01-01

    The subventricular zone (SVZ) provides a constant supply of new neurons to the olfactory bulb (OB). Different studies have investigated the role of olfactory sensory input to neural precursor cell (NPC) turnover in the SVZ but it was not addressed if a reduced demand specifically for periglomerular neurons impacts on NPC-traits in the rostral migratory stream (RMS). We here report that membrane type-1 matrix metalloproteinase (MT1-MMP) deficient mice have reduced complexity of the nasal turbinates, decreased sensory innervation of the OB, reduced numbers of olfactory glomeruli and reduced OB-size without alterations in SVZ neurogenesis. Large parts of the RMS were fully preserved in MT1-MMP-deficient mice, but we detected an increase in cell death-levels and a decrease in SVZ-derived neuroblasts in the distal RMS, as compared to controls. BrdU-tracking experiments showed that homing of NPCs specifically to the glomerular layer was reduced in MT1-MMP-deficient mice in contrast to controls while numbers of tracked cells remained equal in other OB-layers throughout all experimental groups. Altogether, our data show the demand for olfactory interneurons in the glomerular layer modulates cell turnover in the RMS, but has no impact on subventricular neurogenesis. PMID:27573347

  15. Decreased demand for olfactory periglomerular cells impacts on neural precursor cell viability in the rostral migratory stream

    PubMed Central

    Langenfurth, Anika; Gu, Song; Bautze, Verena; Zhang, Caiyi; Neumann, Julia E.; Schüller, Ulrich; Stock, Kristin; Wolf, Susanne A.; Maier, Anna-Maria; Mastrella, Giorgia; Pak, Andrew; Cheng, Hongwei; Kälin, Roland E.; Holmbeck, Kenn; Strotmann, Jörg; Kettenmann, Helmut; Glass, Rainer

    2016-01-01

    The subventricular zone (SVZ) provides a constant supply of new neurons to the olfactory bulb (OB). Different studies have investigated the role of olfactory sensory input to neural precursor cell (NPC) turnover in the SVZ but it was not addressed if a reduced demand specifically for periglomerular neurons impacts on NPC-traits in the rostral migratory stream (RMS). We here report that membrane type-1 matrix metalloproteinase (MT1-MMP) deficient mice have reduced complexity of the nasal turbinates, decreased sensory innervation of the OB, reduced numbers of olfactory glomeruli and reduced OB-size without alterations in SVZ neurogenesis. Large parts of the RMS were fully preserved in MT1-MMP-deficient mice, but we detected an increase in cell death-levels and a decrease in SVZ-derived neuroblasts in the distal RMS, as compared to controls. BrdU-tracking experiments showed that homing of NPCs specifically to the glomerular layer was reduced in MT1-MMP-deficient mice in contrast to controls while numbers of tracked cells remained equal in other OB-layers throughout all experimental groups. Altogether, our data show the demand for olfactory interneurons in the glomerular layer modulates cell turnover in the RMS, but has no impact on subventricular neurogenesis. PMID:27573347

  16. Proliferation and differentiation of oligodendrocyte progenitor cells induced from rat embryonic neural precursor cells followed by flow cytometry.

    PubMed

    Lü, He-Zuo; Wang, Yan-Xia; Li, Ying; Fu, Sai-Li; Hang, Qin; Lu, Pei-Hua

    2008-08-01

    Previous studies have shown that a cell-intrinsic timer might determine when oligodendrocyte progenitor cells (OPCs) isolated from the central nervous system (CNS) stop dividing and initiate differentiation in a defined environment. In this report, the proliferation and differentiation of OPCs induced from neural precursor cells (NPCs) were analyzed by flow cytometry combined with carboxyfluorescein diacetate succinimidyl ester labeling and propidium iodide staining, respectively. When OPCs were cultured in OPC-medium, more than 30% of cells were in S- and G2/M-phases, and continuously self-renewed without differentiation. After exposure to thyroid hormone, there was an obvious decrease in the fraction of cells in both S- and G2/M-phases (<10%). Furthermore, the OPCs no longer proliferated, but differentiated into oligodendrocytes. The dynamic proliferation and differentiation characteristics of OPCs induced from NPCs and analyzed by flow cytometry were similar to those of OPCs isolated from the CNS and analyzed by other methods. These studies indicated that the proliferation and differentiation of OPCs can be followed simply and rapidly by flow cytometry. PMID:18473382

  17. Neural precursor cell cultures from GM2 gangliosidosis animal models recapitulate the biochemical and molecular hallmarks of the brain pathology.

    PubMed

    Martino, Sabata; di Girolamo, Ilaria; Cavazzin, Chiara; Tiribuzi, Roberto; Galli, Rossella; Rivaroli, Anna; Valsecchi, Manuela; Sandhoff, Konrad; Sonnino, Sandro; Vescovi, Angelo; Gritti, Angela; Orlacchio, Aldo

    2009-04-01

    In this work we showed that genotype-related patterns of hexosaminidase activity, isoenzyme composition, gene expression and ganglioside metabolism observed during embryonic and postnatal brain development are recapitulated during the progressive stages of neural precursor cell (NPC) differentiation to mature glia and neurons in vitro. Further, by comparing NPCs and their differentiated progeny established from Tay-Sachs (TS) and Sandhoff (SD) animal models with the wild-type counterparts, we studied the events linking the accumulation of undegraded substrates to hexosaminidase activity. We showed that similarly to what observed in brain tissues in TS NPCs and progeny, the stored GM2 was partially converted by sialidase to GA2, which can be then degraded in the lysosomes to its components. The latter can be used in a salvage pathway for the formation of GM3. Interestingly, results obtained from ganglioside feeding assays and from measurement of lysosomal sialidase activity suggest that a similar pathway might work also in the SD model. PMID:19166507

  18. The balance of Id3 and E47 determines neural stem/precursor cell differentiation into astrocytes.

    PubMed

    Bohrer, Christian; Pfurr, Sabrina; Mammadzada, Könül; Schildge, Sebastian; Plappert, Leandra; Hils, Miriam; Pous, Lauriane; Rauch, Katharina S; Dumit, Verónica I; Pfeifer, Dietmar; Dengjel, Jörn; Kirsch, Matthias; Schachtrup, Kristina; Schachtrup, Christian

    2015-11-12

    Adult neural stem/precursor cells (NSPCs) of the subventricular zone (SVZ) are an endogenous source for neuronal replacement in CNS disease. However, adult neurogenesis is compromised after brain injury in favor of a glial cell fate, which is mainly attributed to changes in the NSPC environment. Yet, it is unknown how this unfavorable extracellular environment translates into a transcriptional program altering NSPC differentiation. Here, we show that genetic depletion of the transcriptional regulator Id3 decreased the number of astrocytes generated from SVZ-derived adult NSPCs in the cortical lesion area after traumatic brain injury. Cortical brain injury resulted in rapid BMP-2 and Id3 up-regulation in the SVZ stem cell niche. Id3(-/-) adult NSPCs failed to differentiate into BMP-2-induced astrocytes, while NSPCs deficient for the Id3-controlled transcription factor E47 readily differentiated into astrocytes in the absence of BMP-2. Mechanistically, E47 repressed the expression of several astrocyte-specific genes in adult NSPCs. These results identify Id3 as the BMP-2-induced transcriptional regulator, promoting adult NSPC differentiation into astrocytes upon CNS injury and reveal a molecular link between environmental changes and NSPC differentiation in the CNS after injury. PMID:26438726

  19. Transcriptomic study of mouse embryonic neural stem cell differentiation under ethanol treatment.

    PubMed

    Mandal, Chanchal; Park, Ji Hyun; Choi, Mi Ran; Kim, Sun Hwa; Badejo, Abimbola Comfort; Chai, Jin Choul; Lee, Young Seek; Jung, Kyoung Hwa; Chai, Young Gyu

    2015-07-01

    Neural stem cells (NSCs) can be differentiated into one of three cell lineages: neurons, astrocytes or, oligodendrocytes. Some neurotoxins have the ability to deregulate this dynamic process. NSC cell fate can be altered by ethanol as reported previously. Our aim was to investigate the alteration of genes by ethanol during NSC differentiation and to explore the molecular mechanism underlying this phenomenon. Here, mouse fetal forebrain derived NSCs were differentiated for 2 days with or without of ethanol (50 mM). We performed a comparative microarray analysis at day two using GeneChip(®) Mouse Genome 430A 2.0 arrays. Microarray analysis showed that the expressions of 496 genes were altered by ethanol (56 and 440 were up- and down-regulated, respectively). Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed the association of the following altered genes in the Wnt signaling pathway: Wnt5a, Csnk2a1, Tcf7l2, Ccnd2, Nlk, Tbl1x, Tbl1xr1, Rac2 and Nfatc3. Quantitative real time PCR analysis also demonstrated the relative expression levels of these genes. As Wnt signaling is a player of brain development, ethanol-induced alterations may contribute to improper development of the brain. Our data could be a useful resource for elucidating the mechanism behind the ethanol neurotoxicity in developing brain. PMID:25697417

  20. Designer Self-Assembling Peptide Nanofiber Scaffolds for Adult Mouse Neural Stem Cell 3-Dimensional Cultures

    PubMed Central

    Gelain, Fabrizio; Bottai, Daniele; Vescovi, Angleo; Zhang, Shuguang

    2006-01-01

    Biomedical researchers have become increasingly aware of the limitations of conventional 2-dimensional tissue cell culture systems, including coated Petri dishes, multi-well plates and slides, to fully address many critical issues in cell biology, cancer biology and neurobiology, such as the 3-D microenvironment, 3-D gradient diffusion, 3-D cell migration and 3-D cell-cell contact interactions. In order to fully understand how cells behave in the 3-D body, it is important to develop a well-controlled 3-D cell culture system where every single ingredient is known. Here we report the development of a 3-D cell culture system using a designer peptide nanofiber scaffold with mouse adult neural stem cells. We attached several functional motifs, including cell adhesion, differentiation and bone marrow homing motifs, to a self-assembling peptide RADA16 (Ac-RADARADARADARADA-COHN2). These functionalized peptides undergo self-assembly into a nanofiber structure similar to Matrigel. During cell culture, the cells were fully embedded in the 3-D environment of the scaffold. Two of the peptide scaffolds containing bone marrow homing motifs significantly enhanced the neural cell survival without extra soluble growth and neurotrophic factors to the routine cell culture media. In these designer scaffolds, the cell populations with β-Tubulin+, GFAP+ and Nestin+ markers are similar to those found in cell populations cultured on Matrigel. The gene expression profiling array experiments showed selective gene expression, possibly involved in neural stem cell adhesion and differentiation. Because the synthetic peptides are intrinsically pure and a number of desired function cellular motifs are easy to incorporate, these designer peptide nanofiber scaffolds provide a promising controlled 3-D culture system for diverse tissue cells, and are useful as well for general molecular and cell biology. PMID:17205123

  1. Transcranial laser therapy alters amyloid precursor protein processing and improves mitochondrial function in a mouse model of Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    McCarthy, Thomas; Yu, Jin; El-Amouri, Salim; Gattoni-Celli, Sebastiano; Richieri, Steve; De Taboada, Luis; Streeter, Jackson; Kindy, Mark S.

    2011-03-01

    Transcranial laser therapy (TLT) using a near-infrared energy laser system was tested in the 2x Tg amyloid precursor protein (APP) mouse model of Alzheimer's Disease (AD). TLT was administered 3 times/week at escalating doses, starting at 3 months of age, and was compared to a control group which received no laser treatment. Treatment sessions were continued for a total of six months. The brains were examined for amyloid plaque burden, Aβ peptides (Aβ1-40 and Aβ1-42 ), APP cleavage products (sAPPα, CTFβ) and mitochondrial activity. Administration of TLT was associated with a significant, dose-dependent reduction in amyloid load as indicated by the numbers of Aβ plaques. Levels of Aβ1-40 and Aβ1-42 levels were likewise reduced in a dose-dependent fashion. All TLT doses produced an increase in brain sAPPα and a decrease in CTFβ levels consistent with an increase in α-secretase activity and a decrease in β-secretase activity. In addition, TLT increased ATP levels and oxygen utilization in treated animals suggesting improved mitochondrial function. These studies suggest that TLT is a potential candidate for treatment of AD.

  2. Investigation of close interactions between sympathetic neural fibres and the follicular dendritic cells network in the mouse spleen.

    PubMed

    Demonceau, Caroline; Marshall, A S; Sales, J; Heinen, E

    2008-01-01

    In this study, co-localization between sympathetic neural fibres and the follicular dendritic cells (FDCs) network was observed within the mouse spleen by confocal technology. Immunohistochemical techniques were used to reveal the rare interactions between the FDCs network and sympathetic neural fibres. We estimated the frequency of three kinds of close interactions which could be defined as overlaps, contacts or neural fibres closer than 10 microm from a FDCs network. Using these estimates, a comparison was made between five uninfected mouse strains exhibiting the same Prnpa genotype but showing different incubation periods when inoculated with primary bovine spongiform encephalopathy (BSE)-infected brain. In prion disease, infectivity is generally detected in the spleen much earlier than in the brain, especially after peripheral inoculation. The way by which the infectious agent reaches the central nervous system is still unclear. From the five mouse strains, we obtained differences in the proportion of splenic FDCs networks with close interactions. Our work suggests that the percentage of splenic FDCs networks with at least one sympathetic neural fibre in close vicinity may influence the length of incubation period. PMID:18591154

  3. Chronic cocaine exposure impairs progenitor proliferation but spares survival and maturation of neural precursors in adult rat dentate gyrus.

    PubMed

    Domínguez-Escribà, L; Hernández-Rabaza, V; Soriano-Navarro, M; Barcia, J A; Romero, F J; García-Verdugo, J M; Canales, J J

    2006-07-01

    Recent observations indicate that drugs of abuse, including alcohol and opiates, impair adult neurogenesis in the hippocampus. We have studied in rats the impact of cocaine treatment (20 mg/kg, daily, i.p.) on cell proliferation, survival and maturation following short-term (8-day) and long-term (24-day) exposure. Using 5'-bromo-2-deoxyuridine (BrdU) and Ki-67 as mitotic markers at the end of the drug treatments, we found that both short- and long-term cocaine exposures significantly reduced cell proliferation in the dentate gyrus (DG) of the hippocampus. By labelling mitotic cells with BrdU pulses before or during the early stages of the drug treatment, we determined that long-term cocaine exposure did not affect the survival of newly generated cells. In register with this finding, cocaine chronic exposure did not increase the number of apoptotic cells labelled by TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling). Using doublecortin (DCX) immunocytochemistry and electron microscopy, we next examined the effects of cocaine exposure on the maturation of the neural precursors and on synaptic output to CA3. DCX immunocytochemistry showed that immature hippocampal cells of rats exposed to cocaine displayed normal arborization patterns and similar degrees of colocalization with BrdU at two different developmental stages. Moreover, cocaine did not produce significant morphological alterations of the mossy fibre projection system to stratum lucidum in the CA3 area of the hippocampus. The results presented demonstrate that chronic cocaine exposure impairs proliferation dynamics in the DG without significantly altering either the survival and growth of immature cells or the structural features of terminal projections to CA3. PMID:16903860

  4. Co-transplantation of syngeneic mesenchymal stem cells improves survival of allogeneic glial-restricted precursors in mouse brain.

    PubMed

    Srivastava, Amit K; Bulte, Camille A; Shats, Irina; Walczak, Piotr; Bulte, Jeff W M

    2016-01-01

    Loss of functional cells from immunorejection during the early post-transplantation period is an important factor that reduces the efficacy of stem cell-based therapies. Recent studies have shown that transplanted mesenchymal stem cells (MSCs) can exert therapeutic effects by secreting anti-inflammatory and pro-survival trophic factors. We investigated whether co-transplantation of MSCs could improve the survival of other transplanted therapeutic cells. Allogeneic glial-restricted precursors (GRPs) were isolated from the brain of a firefly luciferase transgenic FVB mouse (at E13.5 stage) and intracerebrally transplanted, either alone, or together with syngeneic MSCs in immunocompetent BALB/c mice (n=20) or immunodeficient Rag2(-/-) mice as survival control (n=8). No immunosuppressive drug was given to any animal. Using bioluminescence imaging (BLI) as a non-invasive readout of cell survival, we found that co-transplantation of MSCs significantly improved (p<0.05) engrafted GRP survival. No significant change in signal intensities was observed in immunodeficient Rag2(-/-) mice, with transplanted cells surviving in both the GRP only and the GRP+MSC group. In contrast, on day 21 post-transplantation, we observed a 94.2% decrease in BLI signal intensity in immunocompetent mice transplanted with GRPs alone versus 68.1% in immunocompetent mice co-transplanted with MSCs and GRPs (p<0.05). Immunohistochemical analysis demonstrated a lower number of infiltrating CD45, CD11b(+) and CD8(+) cells, reduced astrogliosis, and a higher number of FoxP3(+) cells at the site of transplantation for the immunocompetent mice receiving MSCs. The present study demonstrates that co-transplantation of MSCs can be used to create a microenvironment that is more conducive to the survival of allogeneic GRPs. PMID:26515691

  5. On becoming neural: what the embryo can tell us about differentiating neural stem cells

    PubMed Central

    Moody, Sally A; Klein, Steven L; Karpinski, Beverley A; Maynard, Thomas M; LaMantia, Anthony-Samuel

    2013-01-01

    The earliest steps of embryonic neural development are orchestrated by sets of transcription factors that control at least three processes: the maintenance of proliferative, pluripotent precursors that expand the neural ectoderm; their transition to neurally committed stem cells comprising the neural plate; and the onset of differentiation of neural progenitors. The transition from one step to the next requires the sequential activation of each gene set and then its down-regulation at the correct developmental times. Herein, we review how these gene sets interact in a transcriptional network to regulate these early steps in neural development. A key gene in this regulatory network is FoxD4L1, a member of the forkhead box (Fox) family of transcription factors. Knock-down experiments in Xenopus embryos show that FoxD4L1 is required for the expression of the other neural transcription factors, whereas increased FoxD4L1 levels have three different effects on these genes: up-regulation of neural ectoderm precursor genes; transient down-regulation of neural plate stem cell genes; and down-regulation of neural progenitor differentiation genes. These different effects indicate that FoxD4L1 maintains neural ectodermal precursors in an immature, proliferative state, and counteracts premature neural stem cell and neural progenitor differentiation. Because it both up-regulates and down-regulates genes, we characterized the regions of the FoxD4L1 protein that are specifically involved in these transcriptional functions. We identified a transcriptional activation domain in the N-terminus and at least two domains in the C-terminus that are required for transcriptional repression. These functional domains are highly conserved in the mouse and human homologues. Preliminary studies of the related FoxD4 gene in cultured mouse embryonic stem cells indicate that it has a similar role in promoting immature neural ectodermal precursors and delaying neural progenitor differentiation

  6. Neural precursors (NPCs) from adult L967Q mice display early commitment to "in vitro" neuronal differentiation and hyperexcitability.

    PubMed

    DiFebo, Francesca; Curti, Daniela; Botti, Francesca; Biella, Gerardo; Bigini, Paolo; Mennini, Tiziana; Toselli, Mauro

    2012-08-01

    The pathogenic factors leading to selective degeneration of motoneurons in ALS are not yet understood. However, altered functionality of voltage-dependent Na(+) channels may play a role since cortical hyperexcitability was described in ALS patients and riluzole, the only drug approved to treat ALS, seems to decrease glutamate release via blockade or inactivation of voltage-dependent Na(+) channels. The wobbler mouse, a murine model of motoneuron degeneration, shares some of the clinical features of human ALS. At early stages of the wobbler disease, increased cortical hyperexcitability was observed. Moreover, riluzole reduced motoneuron loss and muscular atrophy in treated wobbler mice. Here, we focussed our attention on specific electrophysiological properties, like voltage-activated Na(+) currents and underlying regenerative electrical activity, as read-outs of the neuronal maturation process of neural stem/progenitor cells (NPCs) isolated from the subventricular zone (SVZ) of adult early symptomatic wobbler mice. In self-renewal conditions, the rate of wobbler NPC proliferation "in vitro" was 30% lower than that of healthy mice. Conversely, the number of wobbler NPCs displaying early neuronal commitment and action potentials was significantly higher. Upon switching from proliferative to differentiative conditions, NPCs underwent significant changes in the key properties of voltage gated Na(+) currents. The most notable finding, in cells with neuronal morphology, was an increase in Na(+) current density that strictly correlated with an increased probability to generate action potentials. This feature was remarkably more pronounced in neurons differentiated from wobbler NPCs that upon sustained stimulation, displayed short trains of pathological facilitation. In agreement with this result, an increase in the number of c-Fos positive cells, a surrogate marker of neuronal network activation, was observed in the mesial cortex of the wobbler mice "in situ". Thus these

  7. Altered behavior and neural activity in conspecific cagemates co-housed with mouse models of brain disorders.

    PubMed

    Yang, Hyunwoo; Jung, Seungmoon; Seo, Jinsoo; Khalid, Arshi; Yoo, Jung-Seok; Park, Jihyun; Kim, Soyun; Moon, Jangsup; Lee, Soon-Tae; Jung, Keun-Hwa; Chu, Kon; Lee, Sang Kun; Jeon, Daejong

    2016-09-01

    The psychosocial environment is one of the major contributors of social stress. Family members or caregivers who consistently communicate with individuals with brain disorders are considered at risk for physical and mental health deterioration, possibly leading to mental disorders. However, the underlying neural mechanisms of this phenomenon remain poorly understood. To address this, we developed a social stress paradigm in which a mouse model of epilepsy or depression was housed long-term (>4weeks) with normal conspecifics. We characterized the behavioral phenotypes and electrophysiologically investigated the neural activity of conspecific cagemate mice. The cagemates exhibited deficits in behavioral tasks assessing anxiety, locomotion, learning/memory, and depression-like behavior. Furthermore, they showed severe social impairment in social behavioral tasks involving social interaction or aggression. Strikingly, behavioral dysfunction remained in the cagemates 4weeks following co-housing cessation with the mouse models. In an electrophysiological study, the cagemates showed an increased number of spikes in medial prefrontal cortex (mPFC) neurons. Our results demonstrate that conspecifics co-housed with mouse models of brain disorders develop chronic behavioral dysfunctions, and suggest a possible association between abnormal mPFC neural activity and their behavioral pathogenesis. These findings contribute to the understanding of the psychosocial and psychiatric symptoms frequently present in families or caregivers of patients with brain disorders. PMID:27211331

  8. Generation of Integration-free Induced Neural Stem Cells from Mouse Fibroblasts.

    PubMed

    Kim, Sung Min; Kim, Jong-Wan; Kwak, Tae Hwan; Park, Sang Woong; Kim, Kee-Pyo; Park, Hyunji; Lim, Kyung Tae; Kang, Kyuree; Kim, Jonghun; Yang, Ji Hun; Han, Heonjong; Lee, Insuk; Hyun, Jung Keun; Bae, Young Min; Schöler, Hans R; Lee, Hoon Taek; Han, Dong Wook

    2016-07-01

    The viral vector-mediated overexpression of the defined transcription factors, Brn4/Pou3f4, Sox2, Klf4, and c-Myc (BSKM), could induce the direct conversion of somatic fibroblasts into induced neural stem cells (iNSCs). However, viral vectors may be randomly integrated into the host genome thereby increasing the risk for undesired genotoxicity, mutagenesis, and tumor formation. Here we describe the generation of integration-free iNSCs from mouse fibroblasts by non-viral episomal vectors containing BSKM. The episomal vector-derived iNSCs (e-iNSCs) closely resemble control NSCs, and iNSCs generated by retrovirus (r-iNSCs) in morphology, gene expression profile, epigenetic status, and self-renewal capacity. The e-iNSCs are functionally mature, as they could differentiate into all the neuronal cell types both in vitro and in vivo Our study provides a novel concept for generating functional iNSCs using a non-viral, non-integrating, plasmid-based system that could facilitate their biomedical applicability. PMID:27189941

  9. Live imaging of apoptosis in a novel transgenic mouse highlights its role in neural tube closure.

    PubMed

    Yamaguchi, Yoshifumi; Shinotsuka, Naomi; Nonomura, Keiko; Takemoto, Kiwamu; Kuida, Keisuke; Yosida, Hiroki; Miura, Masayuki

    2011-12-12

    Many cells die during development, tissue homeostasis, and disease. Dysregulation of apoptosis leads to cranial neural tube closure (NTC) defects like exencephaly, although the mechanism is unclear. Observing cells undergoing apoptosis in a living context could help elucidate their origin, behavior, and influence on surrounding tissues, but few tools are available for this purpose, especially in mammals. In this paper, we used insulator sequences to generate a transgenic mouse that stably expressed a genetically encoded fluorescence resonance energy transfer (FRET)-based fluorescent reporter for caspase activation and performed simultaneous time-lapse imaging of apoptosis and morphogenesis in living embryos. Live FRET imaging with a fast-scanning confocal microscope revealed that cells containing activated caspases showed typical and nontypical apoptotic behavior in a region-specific manner during NTC. Inhibiting caspase activation perturbed and delayed the smooth progression of cranial NTC, which might increase the risk of exencephaly. Our results suggest that caspase-mediated cell removal facilitates NTC completion within a limited developmental window. PMID:22162136

  10. Impact of neural cell adhesion molecule deletion on regeneration after mouse spinal cord injury.

    PubMed

    Saini, Vedangana; Loers, Gabriele; Kaur, Gurcharan; Schachner, Melitta; Jakovcevski, Igor

    2016-07-01

    The neural cell adhesion molecule (NCAM) plays important functional roles in development of the nervous system. We investigated the influence of a constitutive ablation of NCAM on the outcome of spinal cord injury. Transgenic mice lacking NCAM (NCAM-/-) were subjected to severe compression injury of the lower thoracic spinal cord using wild-type (NCAM+/+) littermates as controls. According to the single-frame motion analysis, the NCAM-/- mice showed reduced locomotor recovery in comparison to control mice at 3 and 6 weeks after injury, indicating an overall positive impact of NCAM on recovery after injury. Also the Basso Mouse Scale score was lower in NCAM-/- mice at 3 weeks after injury, whereas at 6 weeks after injury the difference between genotypes was not statistically significant. Worse locomotor function was associated with decreased monoaminergic and cholinergic innervation of the spinal cord caudal to the injury site and decreased axonal regrowth/sprouting at the site of injury. Astrocytic scar formation at the injury site, as assessed by immunohistology for glial fibrillary acidic protein at and around the lesion site was increased in NCAM-/- compared with NCAM+/+ mice. Migration of cultured monolayer astrocytes from NCAM-/- mice was reduced as assayed by scratch wounding. Numbers of Iba-1 immunopositive microglia were not different between genotypes. We conclude that constitutive NCAM deletion in young adult mice reduces recovery after spinal cord injury, validating the hypothesized beneficial role of this molecule in recovery after injury. PMID:27178448

  11. A combination of small molecules directly reprograms mouse fibroblasts into neural stem cells.

    PubMed

    Zheng, Jie; Choi, Kyung-Ah; Kang, Phil Jun; Hyeon, Solji; Kwon, Suhyun; Moon, Jai-Hee; Hwang, Insik; Kim, Yang In; Kim, Yoon Sik; Yoon, Byung Sun; Park, Gyuman; Lee, JangBo; Hong, SungHoi; You, Seungkwon

    2016-07-15

    The generation of induced neural stem cells (iNSCs) from somatic cells using defined factors provides new avenues for basic research and cell therapies for various neurological diseases, such as Parkinson's disease, Huntington's disease, and spinal cord injuries. However, the transcription factors used for direct reprogramming have the potential to cause unexpected genetic modifications, which limits their potential application in cell therapies. Here, we show that a combination of four chemical compounds resulted in cells directly acquiring a NSC identity; we termed these cells chemically-induced NSCs (ciNSCs). ciNSCs expressed NSC markers (Pax6, PLZF, Nestin, Sox2, and Sox1) and resembled NSCs in terms of their morphology, self-renewal, gene expression profile, and electrophysiological function when differentiated into the neuronal lineage. Moreover, ciNSCs could differentiate into several types of mature neurons (dopaminergic, GABAergic, and cholinergic) as well as astrocytes and oligodendrocytes in vitro. Taken together, our results suggest that stably expandable and functional ciNSCs can be directly reprogrammed from mouse fibroblasts using a combination of small molecules without any genetic manipulation, and will provide a new source of cells for cellular replacement therapy of neurodegenerative diseases. PMID:27207831

  12. An update to the list of mouse mutants with neural tube closure defects and advances toward a complete genetic perspective of neural tube closure.

    PubMed

    Harris, Muriel J; Juriloff, Diana M

    2010-08-01

    The number of mouse mutants and strains with neural tube defects (NTDs) now exceeds 240, including 205 representing specific genes, 30 for unidentified genes, and 9 multifactorial strains. These mutants identify genes needed for embryonic neural tube closure. Reports of 50 new NTD mutants since our 2007 review (Harris and Juriloff, 2007) were considered in relation to the previously reviewed mutants to obtain new insights into mechanisms of NTD etiology. In addition to null mutations, some are hypomorphs or conditional mutants. Some mutations do not cause NTDs on their own, but do so in digenic, trigenic, and oligogenic combinations, an etiology that likely parallels the nature of genetic etiology of human NTDs. Mutants that have only exencephaly are fourfold more frequent than those that have spina bifida aperta with or without exencephaly. Many diverse cellular functions and biochemical pathways are involved; the NTD mutants draw new attention to chromatin modification (epigenetics), the protease-activated receptor cascade, and the ciliopathies. Few mutants directly involve folate metabolism. Prevention of NTDs by maternal folate supplementation has been tested in 13 mutants and reduces NTD frequency in six diverse mutants. Inositol reduces spina bifida aperta frequency in the curly tail mutant, and three new mutants involve inositol metabolism. The many NTD mutants are the foundation for a future complete genetic understanding of the processes of neural fold elevation and fusion along mechanistically distinct cranial-caudal segments of the neural tube, and they point to several candidate processes for study in human NTD etiology. PMID:20740593

  13. Identifying Tmem59 related gene regulatory network of mouse neural stem cell from a compendium of expression profiles

    PubMed Central

    2011-01-01

    Background Neural stem cells offer potential treatment for neurodegenerative disorders, such like Alzheimer's disease (AD). While much progress has been made in understanding neural stem cell function, a precise description of the molecular mechanisms regulating neural stem cells is not yet established. This lack of knowledge is a major barrier holding back the discovery of therapeutic uses of neural stem cells. In this paper, the regulatory mechanism of mouse neural stem cell (NSC) differentiation by tmem59 is explored on the genome-level. Results We identified regulators of tmem59 during the differentiation of mouse NSCs from a compendium of expression profiles. Based on the microarray experiment, we developed the parallelized SWNI algorithm to reconstruct gene regulatory networks of mouse neural stem cells. From the inferred tmem59 related gene network including 36 genes, pou6f1 was identified to regulate tmem59 significantly and might play an important role in the differentiation of NSCs in mouse brain. There are four pathways shown in the gene network, indicating that tmem59 locates in the downstream of the signalling pathway. The real-time RT-PCR results shown that the over-expression of pou6f1 could significantly up-regulate tmem59 expression in C17.2 NSC line. 16 out of 36 predicted genes in our constructed network have been reported to be AD-related, including Ace, aqp1, arrdc3, cd14, cd59a, cds1, cldn1, cox8b, defb11, folr1, gdi2, mmp3, mgp, myrip, Ripk4, rnd3, and sncg. The localization of tmem59 related genes and functional-related gene groups based on the Gene Ontology (GO) annotation was also identified. Conclusions Our findings suggest that the expression of tmem59 is an important factor contributing to AD. The parallelized SWNI algorithm increased the efficiency of network reconstruction significantly. This study enables us to highlight novel genes that may be involved in NSC differentiation and provides a shortcut to identifying genes for AD. PMID

  14. Generation and characterization of a novel neural crest marker allele, Inka1-LacZ, reveals a role for Inka1 in mouse neural tube closure

    PubMed Central

    Reid, Bethany S.; Sargent, Thomas D.; Williams, Trevor

    2010-01-01

    Previous studies identified Inka1 as a gene regulated by AP-2α in the neural crest required for craniofacial morphogenesis in fish and frog. Here, we extend the analysis of Inka1 function and regulation to the mouse by generating a LacZ knock-in allele. Inka1-LacZ allele expression occurs in the cephalic mesenchyme, heart, and paraxial mesoderm prior to E8.5. Subsequently, expression is observed in the migratory neural crest cells and their derivatives. Consistent with expression of Inka1 in tissues of the developing head during neurulation, a low percentage of Inka1−/− mice show exencephaly while the remainder are viable and fertile. Further studies indicate that AP-2α is not required for Inka1 expression in the mouse, and suggest that there is no significant genetic interaction between these two factors during embryogenesis. Together, these data demonstrate that while the expression domain of Inka1 is conserved among vertebrates, its function and regulation are not. PMID:20175189

  15. Significant expansion of the REST/NRSF cistrome in human versus mouse embryonic stem cells: potential implications for neural development.

    PubMed

    Rockowitz, Shira; Zheng, Deyou

    2015-07-13

    Recent studies have employed cross-species comparisons of transcription factor binding, reporting significant regulatory network 'rewiring' between species. Here, we address how a transcriptional repressor targets and regulates neural genes differentially between human and mouse embryonic stem cells (ESCs). We find that the transcription factor, Repressor Element 1 Silencing Transcription factor (REST; also called neuron restrictive silencer factor) binds to a core group of ∼1200 syntenic genomic regions in both species, with these conserved sites highly enriched with co-factors, selective histone modifications and DNA hypomethylation. Genes with conserved REST binding are enriched with neural functions and more likely to be upregulated upon REST depletion. Interestingly, we identified twice as many REST peaks in human ESCs compared to mouse ESCs. Human REST cistrome expansion involves additional peaks in genes targeted by REST in both species and human-specific gene targets. Genes with expanded REST occupancy in humans are enriched for learning or memory functions. Analysis of neurological disorder associated genes reveals that Amyotrophic Lateral Sclerosis and oxidative stress genes are particularly enriched with human-specific REST binding. Overall, our results demonstrate that there is substantial rewiring of human and mouse REST cistromes, and that REST may have human-specific roles in brain development and functions. PMID:25990720

  16. Neural stem/progenitor cells differentiate into oligodendrocytes, reduce inflammation, and ameliorate learning deficits after transplantation in a mouse model of traumatic brain injury.

    PubMed

    Koutsoudaki, Paraskevi N; Papastefanaki, Florentia; Stamatakis, Antonios; Kouroupi, Georgia; Xingi, Evangelia; Stylianopoulou, Fotini; Matsas, Rebecca

    2016-05-01

    The central nervous system has limited capacity for regeneration after traumatic injury. Transplantation of neural stem/progenitor cells (NPCs) has been proposed as a potential therapeutic approach while insulin-like growth factor I (IGF-I) has neuroprotective properties following various experimental insults to the nervous system. We have previously shown that NPCs transduced with a lentiviral vector for IGF-I overexpression have an enhanced ability to give rise to neurons in vitro but also in vivo, upon transplantation in a mouse model of temporal lobe epilepsy. Here we studied the regenerative potential of NPCs, IGF-I-transduced or not, in a mouse model of hippocampal mechanical injury. NPC transplantation, with or without IGF-I transduction, rescued the injury-induced spatial learning deficits as revealed in the Morris Water Maze. Moreover, it had beneficial effects on the host tissue by reducing astroglial activation and microglial/macrophage accumulation while enhancing generation of endogenous oligodendrocyte precursor cells. One or two months after transplantation the grafted NPCs had migrated towards the lesion site and in the neighboring myelin-rich regions. Transplanted cells differentiated toward the oligodendroglial, but not the neuronal or astrocytic lineages, expressing the early and late oligodendrocyte markers NG2, Olig2, and CNPase. The newly generated oligodendrocytes reached maturity and formed myelin internodes. Our current and previous observations illustrate the high plasticity of transplanted NPCs which can acquire injury-dependent phenotypes within the host CNS, supporting the fact that reciprocal interactions between transplanted cells and the host tissue are an important factor to be considered when designing prospective cell-based therapies for CNS degenerative conditions. GLIA 2016;64:763-779. PMID:26712314

  17. Functional characterization of neural-restrictive silencer element in mouse pituitary adenylate cyclase-activating polypeptide (PACAP) gene expression.

    PubMed

    Sugawara, Hideki; Tominaga, Aiko; Inoue, Kazuhiko; Takeda, Yasuo; Yamada, Katsushi; Miyata, Atsuro

    2014-11-01

    Pituitary adenylate cyclase-activating polypeptide (PACAP) is predominantly localized in the nervous system, but the underlying mechanism in its neuron-specific expression remains unclear. In addition to two neural-restrictive silencer-like element (NRSLE1 and 2), as reported previously, we have identified the third element in -1,601 to -1,581 bp from the translational initiation site of mouse PACAP gene and termed it as NRSLE3, of which, the sequence and location were highly conserved among mouse, rat, and human PACAP genes. In luciferase reporter assay, the deletion or site-directed mutagenesis of NRSLE3 in the reporter gene construct, driven by heterologous SV40 promoter, cancelled the repression of luciferase activity in non-neuronal Swiss-3T3 cells. Furthermore, its promoter activity was significantly repressed in Swiss-3T3 cells, but not in neuronal-differentiated PC12 cells. The electrophoretic mobility shift assay (EMSA) with nuclear extracts of Swiss-3T3 cells demonstrated a specific complex with NRSLE3 probe that exhibited the same migration with the neural-restrictive silencer element (NRSE) probe of rat type II sodium channel gene. During neuronal differentiation of PC12 cells, the increment of PACAP mRNA exhibited the correlation with that of REST4 mRNA, which is a neuron-specific variant form of neural-restrictive silencer factor (NRSF). In undifferentiated PC12 cells, trichostatin A (TSA), a histone deacetylase (HDAC) inhibitor, which indirectly inhibits NRSF-mediated gene silencing, increased PACAP mRNA level and attenuated the repression of promoter activity of 5' flanking region of mouse PACAP gene containing NRSLEs. These suggest that the NRSE-NRSF system implicates in the regulatory mechanism of neuron-specific expression of PACAP gene. PMID:24939248

  18. Detection of Precursor Lesions of Pancreatic Adenocarcinoma in PET-CT in a Genetically Engineered Mouse Model of Pancreatic Cancer1

    PubMed Central

    Fendrich, Volker; Schneider, Ralph; Maitra, Anirban; Jacobsen, Ilse D; Opfermann, Thomas; Bartsch, Detlef K

    2011-01-01

    Background Pancreatic cancer is among the most dismal of human malignancies. The 5-year survival rate is lower than 5%. The identification of precursor lesions would be the main step to improve this fatal outcome. One precursor lesions are called pancreatic intraepithelial neoplasia (PanIN) and are graduated in grade 1 to 3, whereas grade 3 is classified as carcinoma in situ. Currently, no reliable, noninvasive imaging technique (e.g., ultrasound, computed tomography, magnet resonance imaging) exists to verify PanINs. Methods Recently, a transgenic mouse model of pancreatic cancer was established in which the tumor progression of human pancreatic carcinoma is reproduced. These so-called Pdx-1-Cre; LSL-KrasG12D/+; LSL-Trp53R172H/+mice develop PanINs, which transform to invasive growing pancreatic carcinoma. The pancreata of mice of different ages were immunohistochemically stained using α-GLUT-2 antibodies. Furthermore, mice underwent positron emission tomography (PET)-computed tomography (CT) with 18F-fluorodeoxyglucose (FDG) to evaluate early detection of PanIN lesions. Results An expression of GLUT-2 in murine PanINs was found in PanINs of grade 1B and higher. This finding is associated with an elevated glucose metabolism, leading to the detection of precursor lesions of pancreatic cancer in the FDG PET-CT scan. In addition, immunohistochemical staining of GLUT-2 was detectable in 45 (75%) of 60 human PanINs, whereas PanINs of grade 1B and higher showed a very extensive expression. Conclusions In conclusion, we demonstrate for the first time that an elevated glucose metabolism occurs already in precursor lesions of murine and human pancreatic carcinoma. These findings are the basis for the detection of precursor lesions by PET-CT, thereby helping improving the prognosis of this devastating disease. PMID:21403843

  19. Lipid droplets of neuroepithelial cells are a major calcium storage site during neural tube formation in chick and mouse embryos.

    PubMed

    Bush, K T; Lee, H; Nagele, R G

    1992-05-15

    In situ precipitation of calcium (Ca2+) with fluoride and antimonate shows that Ca(2+)-specific precipitate is localized almost exclusively within lipid droplets of neuroepithelial cells during neural tube formation in chick and mouse embryos. The density of Ca2+ precipitate within lipid droplets is generally greater in the apical ends of cells situated in regions of the neuroepithelium that are actively engaged in bending. These findings suggest that lipid droplets, in addition to providing a source of metabolic fuel for developing neuroepithelial cells, also serve as Ca(2+)-storage and -releasing sites during neurulation. PMID:1601118

  20. In Vivo Transplantation of Enteric Neural Crest Cells into Mouse Gut; Engraftment, Functional Integration and Long-Term Safety

    PubMed Central

    Cooper, Julie E.; McCann, Conor J.; Natarajan, Dipa; Choudhury, Shanas; Boesmans, Werend; Delalande, Jean-Marie; Vanden Berghe, Pieter; Burns, Alan J.; Thapar, Nikhil

    2016-01-01

    Objectives Enteric neuropathies are severe gastrointestinal disorders with unsatisfactory outcomes. We aimed to investigate the potential of enteric neural stem cell therapy approaches for such disorders by transplanting mouse enteric neural crest cells (ENCCs) into ganglionic and aganglionic mouse gut in vivo and analysing functional integration and long-term safety. Design Neurospheres generated from yellow fluorescent protein (YFP) expressing ENCCs selected from postnatal Wnt1-cre;R26R-YFP/YFP murine gut were transplanted into ganglionic hindgut of wild-type littermates or aganglionic hindgut of Ednrbtm1Ywa mice (lacking functional endothelin receptor type-B). Intestines were then assessed for ENCC integration and differentiation using immunohistochemistry, cell function using calcium imaging, and long-term safety using PCR to detect off-target YFP expression. Results YFP+ ENCCs engrafted, proliferated and differentiated into enteric neurons and glia within recipient ganglionic gut. Transplanted cells and their projections spread along the endogenous myenteric plexus to form branching networks. Electrical point stimulation of endogenous nerve fibres resulted in calcium transients (F/F0 = 1.16±0.01;43 cells, n = 6) in YFP+ transplanted ENCCs (abolished with TTX). Long-term follow-up (24 months) showed transplanted ENCCs did not give rise to tumours or spread to other organs (PCR negative in extraintestinal sites). In aganglionic gut ENCCs similarly spread and differentiated to form neuronal and glial networks with projections closely associated with endogenous neural networks of the transition zone. Conclusions Transplanted ENCCs successfully engrafted into recipient ganglionic and aganglionic gut showing appropriate spread, localisation and, importantly, functional integration without any long-term safety issues. This study provides key support for the development and use of enteric neural stem cell therapies. PMID:26824433

  1. Human neural crest cells contribute to coat pigmentation in interspecies chimeras after in utero injection into mouse embryos.

    PubMed

    Cohen, Malkiel A; Wert, Katherine J; Goldmann, Johanna; Markoulaki, Styliani; Buganim, Yosef; Fu, Dongdong; Jaenisch, Rudolf

    2016-02-01

    The neural crest (NC) represents multipotent cells that arise at the interphase between ectoderm and prospective epidermis of the neurulating embryo. The NC has major clinical relevance because it is involved in both inherited and acquired developmental abnormalities. The aim of this study was to establish an experimental platform that would allow for the integration of human NC cells (hNCCs) into the gastrulating mouse embryo. NCCs were derived from pluripotent mouse, rat, and human cells and microinjected into embryonic-day-8.5 embryos. To facilitate integration of the NCCs, we used recipient embryos that carried a c-Kit mutation (W(sh)/W(sh)), which leads to a loss of melanoblasts and thus eliminates competition from the endogenous host cells. The donor NCCs migrated along the dorsolateral migration routes in the recipient embryos. Postnatal mice derived from injected embryos displayed pigmented hair, demonstrating differentiation of the NCCs into functional melanocytes. Although the contribution of human cells to pigmentation in the host was lower than that of mouse or rat donor cells, our results indicate that hNCCs, injected in utero, can integrate into the embryo and form mature functional cells in the animal. This mouse-human chimeric platform allows for a new approach to study NC development and diseases. PMID:26811475

  2. Identification of a mouse brain cDNA that encodes a protein related to the Alzheimer disease-associated amyloid beta protein precursor.

    PubMed Central

    Wasco, W; Bupp, K; Magendantz, M; Gusella, J F; Tanzi, R E; Solomon, F

    1992-01-01

    We have isolated a cDNA from a mouse brain library that encodes a protein whose predicted amino acid sequence is 42% identical and 64% similar to that of the amyloid beta protein precursor (APP). This 653-amino acid protein, which we have termed the amyloid precursor-like protein (APLP), appears to be similar to APP in overall structure as well as amino acid sequence. The amino acid homologies are concentrated within three distinct regions of the two proteins where the identities are 47%, 54%, and 56%. The APLP cDNA hybridizes to two messages of approximately 2.4 and 1.6 kilobases that are present in mouse brain and neuroblastoma cells. Polyclonal antibodies raised against a peptide derived from the C terminus of APLP stain the cytoplasm in a pattern reminiscent of Golgi staining. In addition to APP, APLP also displays significant homology to the Drosophila APP-like protein APPL and a rat testes APP-like protein. These data indicate that the APP gene is a member of a strongly conserved gene family. Studies aimed at determining the functions of the proteins encoded by this gene family should provide valuable clues to their potential role in Alzheimer disease neuropathology. Images PMID:1279693

  3. Modulation of Mouse Embryonic Stem Cell Proliferation and Neural Differentiation by the P2X7 Receptor

    PubMed Central

    Glaser, Talita; de Oliveira, Sophia La Banca; Cheffer, Arquimedes; Beco, Renata; Martins, Patrícia; Fornazari, Maynara; Lameu, Claudiana; Junior, Helio Miranda Costa; Coutinho-Silva, Robson; Ulrich, Henning

    2014-01-01

    Background Novel developmental functions have been attributed to the P2X7 receptor (P2X7R) including proliferation stimulation and neural differentiation. Mouse embryonic stem cells (ESC), induced with retinoic acid to neural differentiation, closely assemble processes occurring during neuroectodermal development of the early embryo. Principal Findings P2X7R expression together with the pluripotency marker Oct-4 was highest in undifferentiated ESC. In undifferentiated cells, the P2X7R agonist Bz-ATP accelerated cell cycle entry, which was blocked by the specific P2X7R inhibitor KN-62. ESC induced to neural differentiation with retinoic acid, reduced Oct-4 and P2X7R expression. P2X7R receptor-promoted intracellular calcium fluxes were obtained at lower Bz-ATP ligand concentrations in undifferentiated and in neural-differentiated cells compared to other studies. The presence of KN-62 led to increased number of cells expressing SSEA-1, Dcx and β3-tubulin, as well as the number of SSEA-1 and β3-tubulin-double-positive cells confirming that onset of neuroectodermal differentiation and neuronal fate determination depends on suppression of P2X7R activity. Moreover, an increase in the number of Ki-67 positive cells in conditions of P2X7R inhibition indicates rescue of progenitors into the cell cycle, augmenting the number of neuroblasts and consequently neurogenesis. Conclusions In embryonic cells, P2X7R expression and activity is upregulated, maintaining proliferation, while upon induction to neural differentiation P2X7 receptor expression and activity needs to be suppressed. PMID:24798220

  4. Rho-kinase-dependent actin turnover and actomyosin disassembly are necessary for mouse spinal neural tube closure

    PubMed Central

    Escuin, Sarah; Vernay, Bertrand; Savery, Dawn; Gurniak, Christine B.; Witke, Walter; Greene, Nicholas D. E.; Copp, Andrew J.

    2015-01-01

    ABSTRACT The cytoskeleton is widely considered essential for neurulation, yet the mouse spinal neural tube can close despite genetic and non-genetic disruption of the cytoskeleton. To investigate this apparent contradiction, we applied cytoskeletal inhibitors to mouse embryos in culture. Preventing actomyosin cross-linking, F-actin assembly or myosin II contractile activity did not disrupt spinal closure. In contrast, inhibiting Rho kinase (ROCK, for which there are two isoforms ROCK1 and ROCK2) or blocking F-actin disassembly prevented closure, with apical F-actin accumulation and adherens junction disturbance in the neuroepithelium. Cofilin-1-null embryos yielded a similar phenotype, supporting the hypothesis that there is a key role for actin turnover. Co-exposure to Blebbistatin rescued the neurulation defects caused by RhoA inhibition, whereas an inhibitor of myosin light chain kinase, ML-7, had no such effect. We conclude that regulation of RhoA, Rho kinase, LIM kinase and cofilin signalling is necessary for spinal neural tube closure through precise control of neuroepithelial actin turnover and actomyosin disassembly. In contrast, actomyosin assembly and myosin ATPase activity are not limiting for closure. PMID:26040287

  5. Tumourigenicity and Immunogenicity of Induced Neural Stem Cell Grafts Versus Induced Pluripotent Stem Cell Grafts in Syngeneic Mouse Brain.

    PubMed

    Gao, Mou; Yao, Hui; Dong, Qin; Zhang, Hongtian; Yang, Zhijun; Yang, Yang; Zhu, Jianwei; Xu, Minhui; Xu, Ruxiang

    2016-01-01

    Along with the development of stem cell-based therapies for central nervous system (CNS) disease, the safety of stem cell grafts in the CNS, such as induced pluripotent stem cells (iPSCs) and induced neural stem cells (iNSCs), should be of primary concern. To provide scientific basis for evaluating the safety of these stem cells, we determined their tumourigenicity and immunogenicity in syngeneic mouse brain. Both iPSCs and embryonic stem cells (ESCs) were able to form tumours in the mouse brain, leading to tissue destruction along with immune cell infiltration. In contrast, no evidence of tumour formation, brain injury or immune rejection was observed with iNSCs, neural stem cells (NSCs) or mesenchymal stem cells (MSCs). With the help of gene ontology (GO) enrichment analysis, we detected significantly elevated levels of chemokines in the brain tissue and serum of mice that developed tumours after ESC or iPSC transplantation. Moreover, we also investigated the interactions between chemokines and NF-κB signalling and found that NF-κB activation was positively correlated with the constantly rising levels of chemokines, and vice versa. In short, iNSC grafts, which lacked any resulting tumourigenicity or immunogenicity, are safer than iPSC grafts. PMID:27417157

  6. Tumourigenicity and Immunogenicity of Induced Neural Stem Cell Grafts Versus Induced Pluripotent Stem Cell Grafts in Syngeneic Mouse Brain

    PubMed Central

    Gao, Mou; Yao, Hui; Dong, Qin; Zhang, Hongtian; Yang, Zhijun; Yang, Yang; Zhu, Jianwei; Xu, Minhui; Xu, Ruxiang

    2016-01-01

    Along with the development of stem cell-based therapies for central nervous system (CNS) disease, the safety of stem cell grafts in the CNS, such as induced pluripotent stem cells (iPSCs) and induced neural stem cells (iNSCs), should be of primary concern. To provide scientific basis for evaluating the safety of these stem cells, we determined their tumourigenicity and immunogenicity in syngeneic mouse brain. Both iPSCs and embryonic stem cells (ESCs) were able to form tumours in the mouse brain, leading to tissue destruction along with immune cell infiltration. In contrast, no evidence of tumour formation, brain injury or immune rejection was observed with iNSCs, neural stem cells (NSCs) or mesenchymal stem cells (MSCs). With the help of gene ontology (GO) enrichment analysis, we detected significantly elevated levels of chemokines in the brain tissue and serum of mice that developed tumours after ESC or iPSC transplantation. Moreover, we also investigated the interactions between chemokines and NF-κB signalling and found that NF-κB activation was positively correlated with the constantly rising levels of chemokines, and vice versa. In short, iNSC grafts, which lacked any resulting tumourigenicity or immunogenicity, are safer than iPSC grafts. PMID:27417157

  7. Electrospun Fibrous Scaffolds of Poly(glycerol-dodecanedioate) for Engineering Neural Tissues From Mouse Embryonic Stem Cells

    PubMed Central

    Dai, Xizi; Huang, Yen-Chih

    2014-01-01

    For tissue engineering applications, the preparation of biodegradable and biocompatible scaffolds is the most desirable but challenging task.  Among the various fabrication methods, electrospinning is the most attractive one due to its simplicity and versatility. Additionally, electrospun nanofibers mimic the size of natural extracellular matrix ensuring additional support for cell survival and growth. This study showed the viability of the fabrication of long fibers spanning a larger deposit area for a novel biodegradable and biocompatible polymer named poly(glycerol-dodecanoate) (PGD)1 by using a newly designed collector for electrospinning. PGD exhibits unique elastic properties with similar mechanical properties to nerve tissues, thus it is suitable for neural tissue engineering applications. The synthesis and fabrication set-up for making fibrous scaffolding materials was simple, highly reproducible, and inexpensive. In biocompatibility testing, cells derived from mouse embryonic stem cells could adhere to and grow on the electrospun PGD fibers. In summary, this protocol provided a versatile fabrication method for making PGD electrospun fibers to support the growth of mouse embryonic stem cell derived neural lineage cells. PMID:24961272

  8. Nop2 is expressed during proliferation of neural stem cells and in adult mouse and human brain.

    PubMed

    Kosi, Nina; Alić, Ivan; Kolačević, Matea; Vrsaljko, Nina; Jovanov Milošević, Nataša; Sobol, Margarita; Philimonenko, Anatoly; Hozák, Pavel; Gajović, Srećko; Pochet, Roland; Mitrečić, Dinko

    2015-02-01

    The nucleolar protein 2 gene encodes a protein specific for the nucleolus. It is assumed that it plays a role in the synthesis of ribosomes and regulation of the cell cycle. Due to its link to cell proliferation, higher expression of Nop2 indicates a worse tumor prognosis. In this work we used Nop2(gt1gaj) gene trap mouse strain. While lethality of homozygous animals suggested a vital role of this gene, heterozygous animals allowed the detection of expression of Nop2 in various tissues, including mouse brain. Histochemistry, immunohistochemistry and immunoelectron microscopy techniques, applied to a mature mouse brain, human brain and on mouse neural stem cells revealed expression of Nop2 in differentiating cells, including astrocytes, as well as in mature neurons. Nop2 was detected in various regions of mouse and human brain, mostly in large pyramidal neurons. In the human, Nop2 was strongly expressed in supragranular and infragranular layers of the somatosensory cortex and in layer III of the cingulate cortex. Also, Nop2 was detected in CA1 and the subiculum of the hippocampus. Subcellular analyses revealed predominant location of Nop2 within the dense fibrillar component of the nucleolus. To test if Nop2 expression correlates to cell proliferation occurring during tissue regeneration, we induced strokes in mice by middle cerebral artery occlusion. Two weeks after stroke, the number of Nop2/nestin double positive cells in the region affected by ischemia and the periventricular zone substantially increased. Our findings suggest a newly discovered role of Nop2 in both mature neurons and in cells possibly involved in the regeneration of nervous tissue. PMID:25481415

  9. Adoptive precursor cell therapy to enhance immune reconstitution after hematopoietic stem cell transplantation in mouse and man

    PubMed Central

    Holland, Amanda M.; Zakrzewski, Johannes L.; Goldberg, Gabrielle L.; Ghosh, Arnab

    2016-01-01

    Hematopoietic stem cell transplantation is a curative therapy for hematological malignancies. T cell deficiency following transplantation is a major cause of morbidity and mortality. In this review, we discuss adoptive transfer of committed precursor cells to enhance T cell reconstitution and improve overall prognosis after transplantation. PMID:19015856

  10. Insights into prevention of human neural tube defects by folic acid arising from consideration of mouse mutants.

    PubMed

    Harris, Muriel J

    2009-04-01

    Almost 30 years after the initial study by Richard W. Smithells and coworkers, it is still unknown how maternal periconceptional folic acid supplementation prevents human neural tube defects (NTDs). In this article, questions about human NTD prevention are considered in relation to three groups of mouse models: NTD mutants that respond to folate, NTD mutants and strains that do not respond to folate, and mutants involving folate-pathway genes. Of the 200 mouse NTD mutants, only a few have been tested with folate; half respond and half do not. Among responsive mutants, folic acid supplementation reduces exencephaly and/or spina bifida aperta frequency in the Sp(2H), Sp, Cd, Cited2, Cart1, and Gcn5 mutants. Prevention ranges from 35 to 85%. The responsive Sp(2H) (Pax3) mutant has abnormal folate metabolism, but the responsive Cited2 mutant does not. Neither folic nor folinic acid reduces NTD frequency in Axd, Grhl3, Fkbp8, Map3k4, or Nog mutants or in the curly tail or SELH/Bc strains. Spina bifida frequency is reduced in Axd by methionine and in curly tail by inositol. Exencephaly frequency is reduced in SELH/Bc by an alternative commercial ration. Mutations in folate-pathway genes do not cause NTDs, except for 30% exencephaly in folate-treated Folr1. Among folate-pathway mutants, neural tube closure is normal in Cbs, Folr2, Mthfd1, Mthfd2, Mthfr, and Shmt1 mutants. Embryos die by midgestation in Folr1, Mtr, Mtrr, and RFC1 mutants. The mouse models point to genetic heterogeneity in the ability to respond to folic acid and also to heterogeneity in genetic cause of NTDs that can be prevented by folic acid. PMID:19117321

  11. Transcriptomic gene-network analysis of exposure to silver nanoparticle reveals potentially neurodegenerative progression in mouse brain neural cells.

    PubMed

    Lin, Ho-Chen; Huang, Chin-Lin; Huang, Yuh-Jeen; Hsiao, I-Lun; Yang, Chung-Wei; Chuang, Chun-Yu

    2016-08-01

    Silver nanoparticles (AgNPs) are commonly used in daily living products. AgNPs can induce inflammatory response in neuronal cells, and potentially develop neurological disorders. The gene networks in response to AgNPs-induced neurodegenerative progression have not been clarified in various brain neural cells. This study found that 3-5nm AgNPs were detectable to enter the nuclei of mouse neuronal cells after 24-h of exposure. The differentially expressed genes in mouse brain neural cells exposure to AgNPs were further identified using Phalanx Mouse OneArray® chip, and permitted to explore the gene network pathway regulating in neurodegenerative progression according to Cytoscape analysis. In focal adhesion pathway of ALT astrocytes, AgNPs induced the gene expression of RasGRF1 and reduced its downstream BCL2 gene for apoptosis. In cytosolic DNA sensing pathway of microglial BV2 cells, AgNPs reduced the gene expression of TREX1 and decreased IRF7 to release pro-inflammatory cytokines for inflammation and cellular activation. In MAPK pathway of neuronal N2a cells, AgNPs elevated GADD45α gene expression, and attenuated its downstream PTPRR gene to interfere with neuron growth and differentiation. Moreover, AgNPs induced beta amyloid deposition in N2a cells, and decreased PSEN1 and PSEN2, which may disrupt calcium homeostasis and presynaptic dysfunction for Alzheimer's disease development. These findings suggested that AgNPs exposure reveals the potency to induce the progression of neurodegenerative disorder. PMID:27131904

  12. Comparative Analysis Between Flaviviruses Reveals Specific Neural Stem Cell Tropism for Zika Virus in the Mouse Developing Neocortex.

    PubMed

    Brault, Jean-Baptiste; Khou, Cécile; Basset, Justine; Coquand, Laure; Fraisier, Vincent; Frenkiel, Marie-Pascale; Goud, Bruno; Manuguerra, Jean-Claude; Pardigon, Nathalie; Baffet, Alexandre D

    2016-08-01

    The recent Zika outbreak in South America and French Polynesia was associated with an epidemic of microcephaly, a disease characterized by a reduced size of the cerebral cortex. Other members of the Flavivirus genus, including West Nile virus (WNV), can cause encephalitis but were not demonstrated to cause microcephaly. It remains unclear whether Zika virus (ZIKV) and other flaviviruses may infect different cell populations in the developing neocortex and lead to distinct developmental defects. Here, we describe an assay to infect mouse E15 embryonic brain slices with ZIKV, WNV and dengue virus serotype 4 (DENV-4). We show that this tissue is able to support viral replication of ZIKV and WNV, but not DENV-4. Cell fate analysis reveals a remarkable tropism of ZIKV infection for neural stem cells. Closely related WNV displays a very different tropism of infection, with a bias towards neurons. We further show that ZIKV infection, but not WNV infection, impairs cell cycle progression of neural stem cells. Both viruses inhibited apoptosis at early stages of infection. This work establishes a powerful comparative approach to identify ZIKV-specific alterations in the developing neocortex and reveals specific preferential infection of neural stem cells by ZIKV. PMID:27453325

  13. Application of Self Adaptive Unsupervised Neural Networks for Processing of VLF-LF signals to detect Seismic-Ionospheric Precursor Phenomena.

    NASA Astrophysics Data System (ADS)

    Skeberis, C.; Xenos, T. D.; Hadjileontiadis, L.; Contadakis, M. E.; Arabelos, D.

    2012-04-01

    This paper investigates the development and application of artificial neural networks (ANN) based on Predictive Modular Neural Networks (PREMONNs) to provide a self adaptive unsupervised method for detecting disturbances that can be attributed to seismic-ionospheric precursor phenomena using VLF radio signals. As such, the neural network is applied to bring forth and adaptively discriminate different characteristics in the received signals, in real time, in order to provide data segments of interest that can be correlated to subsequent seismic phenomena. PREMONNs have been developed for time series prediction and through that for source switching detection in a time series; they are constituted by two modules. The first tier is a module consisting of a dynamic array of neural networks following the data stream in order to predict the next value of a time series whereas the second is a decision one utilizing a Bayes probability equation to decide on source switching. That module is responsible for electing and appropriately training the closest fitting NN or switching to a new NN if a source switch is apparent. For the purpose of this paper, VLF signals transmitted by a number of European VLF transmitters are monitored for over a year in Thessaloniki (40.69N 22.78E) and the data from December 2010 to December 2011 are used. The received signals are sampled and stored for off line processing. The receiver was developed by Elettronika Srl, and is part of the International Network for Frontier Research on Earthquake Precursors (INFREP). Signals received from the 20.27KHz ICV station in Tavolara, Italy (Lat 40.923,Lon. 9.731) were used. The received VLF signal was normalized and then processed using the Empirical Mode Decomposition Method (EMD). The resulting data are used to train the unsupervised ANN and the performance of the developed network is then evaluated. The efficacy of different layouts of the PREMONN is evaluated and the application of a self

  14. Human neural crest cells contribute to coat pigmentation in interspecies chimeras after in utero injection into mouse embryos

    PubMed Central

    Cohen, Malkiel A.; Wert, Katherine J.; Goldmann, Johanna; Markoulaki, Styliani; Buganim, Yosef; Fu, Dongdong; Jaenisch, Rudolf

    2016-01-01

    The neural crest (NC) represents multipotent cells that arise at the interphase between ectoderm and prospective epidermis of the neurulating embryo. The NC has major clinical relevance because it is involved in both inherited and acquired developmental abnormalities. The aim of this study was to establish an experimental platform that would allow for the integration of human NC cells (hNCCs) into the gastrulating mouse embryo. NCCs were derived from pluripotent mouse, rat, and human cells and microinjected into embryonic-day-8.5 embryos. To facilitate integration of the NCCs, we used recipient embryos that carried a c-Kit mutation (Wsh/Wsh), which leads to a loss of melanoblasts and thus eliminates competition from the endogenous host cells. The donor NCCs migrated along the dorsolateral migration routes in the recipient embryos. Postnatal mice derived from injected embryos displayed pigmented hair, demonstrating differentiation of the NCCs into functional melanocytes. Although the contribution of human cells to pigmentation in the host was lower than that of mouse or rat donor cells, our results indicate that hNCCs, injected in utero, can integrate into the embryo and form mature functional cells in the animal. This mouse–human chimeric platform allows for a new approach to study NC development and diseases. PMID:26811475

  15. Bumetanide promotes neural precursor cell regeneration and dendritic development in the hippocampal dentate gyrus in the chronic stage of cerebral ischemia

    PubMed Central

    Xu, Wang-shu; Sun, Xuan; Song, Cheng-guang; Mu, Xiao-peng; Ma, Wen-ping; Zhang, Xing-hu; Zhao, Chuan-sheng

    2016-01-01

    Bumetanide has been shown to lessen cerebral edema and reduce the infarct area in the acute stage of cerebral ischemia. Few studies focus on the effects of bumetanide on neuroprotection and neurogenesis in the chronic stage of cerebral ischemia. We established a rat model of cerebral ischemia by injecting endothelin-1 in the left cortical motor area and left corpus striatum. Seven days later, bumetanide 200 µg/kg/day was injected into the lateral ventricle for 21 consecutive days with a mini-osmotic pump. Results demonstrated that the number of neuroblasts cells and the total length of dendrites increased, escape latency reduced, and the number of platform crossings increased in the rat hippocampal dentate gyrus in the chronic stage of cerebral ischemia. These findings suggest that bumetanide promoted neural precursor cell regeneration, dendritic development and the recovery of cognitive function, and protected brain tissue in the chronic stage of ischemia. PMID:27335557

  16. Improvement of Neurological Dysfunctions in Aphakia Mice, a Model of Parkinson’s Disease, after Transplantation of ES Cell-Derived Dopaminergic Neuronal Precursors

    PubMed Central

    Chung, Sangmi; Moon, Jisook; Kim, Kwang-Soo

    2016-01-01

    Parkinson’s disease (PD) is characterized by selective death of the substantia nigra dopaminergic neurons, and previously we have shown that aphakia mice, which harbor spontaneous Pitx3 gene mutation, show specific degeneration of the substantia nigra dopaminergic neurons accompanied by behavioral deficits that is reversed by L-DOPA treatment or transplantation of dopaminergic neural precursors. Here, we describe transplantation of dopaminergic neural precursors to a mouse model of PD, an aphakia mouse, followed by behavioral analyses of transplanted mice. PMID:25173391

  17. Adenosine A(1), A(2a), A(2b), and A(3) receptors in hematopoiesis. 1. Expression of receptor mRNA in four mouse hematopoietic precursor cells.

    PubMed

    Streitová, D; Sefc, L; Savvulidi, F; Pospísil, M; Holá, J; Hofer, M

    2010-01-01

    Four mouse bone marrow or thymus cell populations, namely granulopoietic/monocytopoietic, erythropoietic, B-lymphopoietic, and T-lymphopoietic precursor cells have been assayed by RT-PCR technique for the presence and relative amounts of adenosine A(1), A(2a), A(2b), and A(3) receptor mRNA. It has been found that (i) all four populations studied express all four adenosine receptor subtypes, (ii) the A(1), receptor is the least expressed in all populations studied, (iii) the A(3) receptor is markedly expressed in the populations of granulopoietic/monocytopoietic and erythropoietic cells, (iv) the A(2a) receptor is markedly expressed in the populations of B-lymphopoietic and T-lymphopoietic cells, and v) the A(2b) receptor does not predominate in any of the precursor cells studied. Our data offer a new possibility for the assessment of the readiness of these cells to respond, by receptor-mediated mechanisms, to adenosine or its analogs present in the tissues as a result of endogenous processes and/or following their administration. PMID:19249907

  18. Reproducible expansion and characterization of mouse neural stem/progenitor cells in adherent cultures derived from the adult subventricular zone

    PubMed Central

    Theus, Michelle H.; Ricard, Jerome; Liebl, Daniel J.

    2012-01-01

    Endogenous neural stem/progenitor cells (NSPCs) residing in the subventricular zone (SVZ) of the adult mouse forebrain have been shown to enhance their neurogenic potential in response to CNS injury. Mechanisms involved in regulating adult neurogenesis under naïve or stressed conditions can be studied using a monolayer cell-culture system of the nestin-expressing NSPC lineage to analyze proliferation, survival and differentiation. Here, we describe a protocol for the expansion of NSPCs for studies aimed at understanding the functional role of NSPCs in maintaining adult neurogenic processes. In this unit, we outline in detail the procedures for: (1) isolation, maintenance and culture of the NSPC component of the SVZ niche from the lateral wall of the lateral ventricle; (2) characterization of NSPC functions by examining proliferation, survival and differentiation; and (3) efficient siRNA transfection methods in 96-well format. PMID:22415840

  19. Inositol deficiency increases the susceptibility to neural tube defects of genetically predisposed (curly tail) mouse embryos in vitro.

    PubMed

    Cockroft, D L; Brook, F A; Copp, A J

    1992-02-01

    Curly tail (ct/ct) mouse embryos, which have a genetic predisposition for neural tube defects (NTD), were grown in culture from the 2-5 somite stage, before the initiation of neurulation, up to the 22-24 somite stage, when closure of the anterior neural tube is normally complete. The embryos were cultured in whole rat serum or in extensively dialysed serum supplemented with glucose, amino acids, and vitamins, with inositol omitted or added at concentrations of 2, 10, 20, and 50 mg/l. Two strains were used as controls; CBA mice, which are related to curly tails, and an unrelated PO stock. It was found that ct/ct embryos were particularly sensitive to inositol deficiency; both they and the CBA embryos showed a similar high incidence of cranial NTD after culture in inositol deficient medium (12/17 and 11/18, respectively). Furthermore, the lowest dose of inositol had no effect on the frequency of head defects in ct/ct mice, though it halved the incidence in CBA embryos. With higher inositol concentrations, the majority of ct/ct embryos completed head closure normally, and their development was generally similar to that obtained in whole serum. PO embryos showed a lower proportion (5/19) of cranial NTD in the inositol deficient medium than the other two strains, and this was further reduced by even the lowest inositol dose. PMID:1615432

  20. Neurons derived from transplanted neural stem cells restore disrupted neuronal circuitry in a mouse model of spinal cord injury

    PubMed Central

    Abematsu, Masahiko; Tsujimura, Keita; Yamano, Mariko; Saito, Michiko; Kohno, Kenji; Kohyama, Jun; Namihira, Masakazu; Komiya, Setsuro; Nakashima, Kinichi

    2010-01-01

    The body’s capacity to restore damaged neural networks in the injured CNS is severely limited. Although various treatment regimens can partially alleviate spinal cord injury (SCI), the mechanisms responsible for symptomatic improvement remain elusive. Here, using a mouse model of SCI, we have shown that transplantation of neural stem cells (NSCs) together with administration of valproic acid (VPA), a known antiepileptic and histone deacetylase inhibitor, dramatically enhanced the restoration of hind limb function. VPA treatment promoted the differentiation of transplanted NSCs into neurons rather than glial cells. Transsynaptic anterograde corticospinal tract tracing revealed that transplant-derived neurons reconstructed broken neuronal circuits, and electron microscopic analysis revealed that the transplant-derived neurons both received and sent synaptic connections to endogenous neurons. Ablation of the transplanted cells abolished the recovery of hind limb motor function, confirming that NSC transplantation directly contributed to restored motor function. These findings raise the possibility that epigenetic status in transplanted NSCs can be manipulated to provide effective treatment for SCI. PMID:20714104

  1. The TRIM-NHL protein TRIM32 activates microRNAs and prevents self-renewal in mouse neural progenitors.

    PubMed

    Schwamborn, Jens C; Berezikov, Eugene; Knoblich, Juergen A

    2009-03-01

    In the mouse neocortex, neural progenitor cells generate both differentiating neurons and daughter cells that maintain progenitor fate. Here, we show that the TRIM-NHL protein TRIM32 regulates protein degradation and microRNA activity to control the balance between those two daughter cell types. In both horizontally and vertically dividing progenitors, TRIM32 becomes polarized in mitosis and is concentrated in one of the two daughter cells. TRIM32 overexpression induces neuronal differentiation while inhibition of TRIM32 causes both daughter cells to retain progenitor cell fate. TRIM32 ubiquitinates and degrades the transcription factor c-Myc but also binds Argonaute-1 and thereby increases the activity of specific microRNAs. We show that Let-7 is one of the TRIM32 targets and is required and sufficient for neuronal differentiation. TRIM32 is the mouse ortholog of Drosophila Brat and Mei-P26 and might be part of a protein family that regulates the balance between differentiation and proliferation in stem cell lineages. PMID:19269368

  2. Magnesium regulates neural stem cell proliferation in the mouse hippocampus by altering mitochondrial function.

    PubMed

    Jia, Shanshan; Mou, Chengzhi; Ma, Yihe; Han, Ruijie; Li, Xue

    2016-04-01

    In the adult brain, neural stem cells from the subgranular zone (SGZ) of the hippocampus and the subventricular zone (SVZ) of the cortex progress through the following five developmental stages: radial glia-like cells, neural progenitor cells, neuroblasts, immature neurons, and mature neurons. These developmental stages are linked to both neuronal microenvironments and energy metabolism. Neurogenesis is restricted and has been demonstrated to arise from tissue microenvironments. We determined that magnesium, a key nutrient in cellular energy metabolism, affects neural stem cell (NSC) proliferation in cells derived from the embryonic hippocampus by influencing mitochondrial function. Densities of proliferating cells and NSCs both showed their highest values at 0.8 mM [Mg(2+) ]o , whereas lower proliferation rates were observed at 0.4 and 1.4 mM [Mg(2+) ]o . The numbers and sizes of the neurospheres reached the maximum at 0.8 mM [Mg(2+) ]o and were weaker under both low (0.4 mM) and high (1.4 mM) concentrations of magnesium. In vitro experimental evidence demonstrates that extracellular magnesium regulates the number of cultured hippocampal NSCs, affecting both magnesium homeostasis and mitochondrial function. Our findings indicate that the effect of [Mg(2+) ]o on NSC proliferation may lie downstream of alterations in mitochondrial function because mitochondrial membrane potential was highest in the NSCs in the moderate [Mg(2+) ]o (0.8 mM) group and lower in both the low (0.4 mM) and high (1.4 mM) [Mg(2+) ]o groups. Overall, these findings demonstrate a new function for magnesium in the brain in the regulation of hippocampal neural stem cells: affecting their cellular energy metabolism. PMID:26634890

  3. Taurine Induces Proliferation of Neural Stem Cells and Synapse Development in the Developing Mouse Brain

    PubMed Central

    Shivaraj, Mattu Chetana; Marcy, Guillaume; Low, Guoliang; Ryu, Jae Ryun; Zhao, Xianfeng; Rosales, Francisco J.; Goh, Eyleen L. K.

    2012-01-01

    Taurine is a sulfur-containing amino acid present in high concentrations in mammalian tissues. It has been implicated in several processes involving brain development and neurotransmission. However, the role of taurine in hippocampal neurogenesis during brain development is still unknown. Here we show that taurine regulates neural progenitor cell (NPC) proliferation in the dentate gyrus of the developing brain as well as in cultured early postnatal (P5) hippocampal progenitor cells and hippocampal slices derived from P5 mice brains. Taurine increased cell proliferation without having a significant effect on neural differentiation both in cultured P5 NPCs as well as cultured hippocampal slices and in vivo. Expression level analysis of synaptic proteins revealed that taurine increases the expression of Synapsin 1 and PSD 95. We also found that taurine stimulates the phosphorylation of ERK1/2 indicating a possible role of the ERK pathway in mediating the changes that we observed, especially in proliferation. Taken together, our results demonstrate a role for taurine in neural stem/progenitor cell proliferation in developing brain and suggest the involvement of the ERK1/2 pathways in mediating these actions. Our study also shows that taurine influences the levels of proteins associated with synapse development. This is the first evidence showing the effect of taurine on early postnatal neuronal development using a combination of in vitro, ex-vivo and in vivo systems. PMID:22916184

  4. Derivation of Schwann cell precursors from neural crest cells resident in bone marrow for cell therapy to improve peripheral nerve regeneration.

    PubMed

    Shi, Haiyan; Gong, Yanpei; Qiang, Liang; Li, Xiaoli; Zhang, Shibo; Gao, Jiawen; Li, Kai; Ji, Ximeng; Tian, Ling; Gu, Xiaosong; Ding, Fei

    2016-05-01

    We have previously successfully enriched post-migratory neural crest cells (NCCs) from postnatal rat bone marrow (BM). These BM-NCCs possess glial and neuronal differentiating potential. Based on the neural crest origin of Schwann cells (SCs), in this study, we aimed at using a straightforward protocol to derive Schwann cell precursors (SCPs) from BM-NCCs. Several clonal subpopulations were isolated from BM-NCCs, displaying long-term proliferative capacity and maintaining the NCC identity. The BM-NCC clones could be induced to differentiate into SCs. In particular, clone N1 gave rise to a large and pure population of SCs. Clone N1-derived SCs demonstrated the myelinating capacity in their co-culture with primary dorsal root ganglion (DRG) neurons. The decreased expression of NCC-markers and increased expression of SC-markers were related to the differentiation state of clone N1-derived SCs. To investigate the repair-promoting effects of clone N1 on injured peripheral neurons in vitro and in vivo, on one hand, the oxygen glucose deprivation-injured DRG neurons were treated with clone N1-conditioned medium, improving the cell survival and axon growth of neurons; on the other hand, clone N1 or clone N1-derived SCs were respectively implanted to the crush sciatic nerve of rats, and clone N1 yielded the better outcome of nerve regeneration and function restoration than clone N1-derived SCs. Taken together, all the results collectively showed that clone N1 could be identified as SCPs, which might hold promise for cell therapy to improve peripheral nerve regeneration. PMID:26946403

  5. The long non-coding RNA FMR4 promotes proliferation of human neural precursor cells and epigenetic regulation of gene expression in trans.

    PubMed

    Peschansky, Veronica J; Pastori, Chiara; Zeier, Zane; Wentzel, Katya; Velmeshev, Dmitry; Magistri, Marco; Silva, José P; Wahlestedt, Claes

    2016-07-01

    Triplet repeat expansions in the Fragile X mental retardation 1 (FMR1) gene cause either intellectual disability and autism, or adult-onset neurodegeneration, with poorly understood variability in presentation. Previous studies have identified several long noncoding RNAs (lncRNAs) at the FMR1 locus, including FMR4. Similarly to FMR1, FMR4 is silenced by large-repeat expansions that result in enrichment of DNA and histone methylation within the shared promoter and repeat sequence, suggesting a possible role for this noncoding RNA in the pathophysiology of Fragile X. We therefore assessed the functional role of FMR4 to gain further insight into the molecular processes in Fragile X-associated disorders. Previous work showed that FMR4 does not exhibit cis-regulation of FMR1. Here, we found that FMR4 is a chromatin-associated transcript and, using genome-wide chromatin immunoprecipitation experiments, showed that FMR4 alters the chromatin state and the expression of several hundred genes in trans. Among the genes regulated by FMR4, we found enrichment for those involved in neural development and cellular proliferation. S-phase marker assays further demonstrated that FMR4 may promote cellular proliferation, rather than differentiation, of human neural precursor cells (hNPCs). By establishing this novel function for FMR4 in hNPCs, we lend support to existing evidence of the epigenetic involvement of lncRNA in nervous system development, and increase our understanding of the complex pathogenesis underlying neurological disorders associated with FMR1 repeat expansions. PMID:27001315

  6. Amyloid precursor protein transgenic mouse models and Alzheimer’s disease: Understanding the paradigms, limitations and contributions

    PubMed Central

    Kokjohn, Tyler A.; Roher, Alex E.

    2009-01-01

    Transgenic (Tg) mice overexpressing mutant familial Alzheimer’s disease (AD) amyloid precursor protein (APP) genes have contributed to the understanding of dementia pathology and support the amyloid cascade hypothesis. Although many sophisticated mice APP models exist, none recapitulates AD cellular and behavioral pathology. The morphological resemblance to AD amyloidosis is impressive, but fundamental biophysical and biochemical properties of the APP/Aβ produced in Tg mice differ substantially from those of humans. The greater resilience of Tg mice to substantial Aβ burdens suggests the levels and forms that are deleterious to human neurons are not as noxious in these models. Tg mice have been widely used for testing AD therapeutic agents and demonstrated promising results. Unfortunately, clinical trials resulted in unforeseen adverse events or negative therapeutic outcomes. The disparity between success and failure is in part due to differences in brain environment that separate man and rodent. These observations suggest that the pathogenesis of AD is by far much more intricate than the straightforward accumulation of Aβ. PMID:19560104

  7. Single-Cell Expression Profiling Reveals a Dynamic State of Cardiac Precursor Cells in the Early Mouse Embryo

    PubMed Central

    Kokkinopoulos, Ioannis; Ishida, Hidekazu; Saba, Rie; Ruchaya, Prashant; Cabrera, Claudia; Struebig, Monika; Barnes, Michael; Terry, Anna; Kaneko, Masahiro; Shintani, Yasunori; Coppen, Steven; Shiratori, Hidetaka; Ameen, Torath; Mein, Charles; Hamada, Hiroshi; Suzuki, Ken; Yashiro, Kenta

    2015-01-01

    In the early vertebrate embryo, cardiac progenitor/precursor cells (CPs) give rise to cardiac structures. Better understanding their biological character is critical to understand the heart development and to apply CPs for the clinical arena. However, our knowledge remains incomplete. With the use of single-cell expression profiling, we have now revealed rapid and dynamic changes in gene expression profiles of the embryonic CPs during the early phase after their segregation from the cardiac mesoderm. Progressively, the nascent mesodermal gene Mesp1 terminated, and Nkx2-5+/Tbx5+ population rapidly replaced the Tbx5low+ population as the expression of the cardiac genes Tbx5 and Nkx2-5 increased. At the Early Headfold stage, Tbx5-expressing CPs gradually showed a unique molecular signature with signs of cardiomyocyte differentiation. Lineage-tracing revealed a developmentally distinct characteristic of this population. They underwent progressive differentiation only towards the cardiomyocyte lineage corresponding to the first heart field rather than being maintained as a progenitor pool. More importantly, Tbx5 likely plays an important role in a transcriptional network to regulate the distinct character of the FHF via a positive feedback loop to activate the robust expression of Tbx5 in CPs. These data expands our knowledge on the behavior of CPs during the early phase of cardiac development, subsequently providing a platform for further study. PMID:26469858

  8. MiRNA-128 regulates the proliferation and neurogenesis of neural precursors by targeting PCM1 in the developing cortex

    PubMed Central

    Zhang, Wei; Kim, Paul Jong; Chen, Zhongcan; Lokman, Hidayat; Qiu, Lifeng; Zhang, Ke; Rozen, Steven George; Tan, Eng King; Je, Hyunsoo Shawn; Zeng, Li

    2016-01-01

    During the development, tight regulation of the expansion of neural progenitor cells (NPCs) and their differentiation into neurons is crucial for normal cortical formation and function. In this study, we demonstrate that microRNA (miR)-128 regulates the proliferation and differentiation of NPCs by repressing pericentriolar material 1 (PCM1). Specifically, overexpression of miR-128 reduced NPC proliferation but promoted NPC differentiation into neurons both in vivo and in vitro. In contrast, the reduction of endogenous miR-128 elicited the opposite effects. Overexpression of miR-128 suppressed the translation of PCM1, and knockdown of endogenous PCM1 phenocopied the observed effects of miR-128 overexpression. Furthermore, concomitant overexpression of PCM1 and miR-128 in NPCs rescued the phenotype associated with miR-128 overexpression, enhancing neurogenesis but inhibiting proliferation, both in vitro and in utero. Taken together, these results demonstrate a novel mechanism by which miR-128 regulates the proliferation and differentiation of NPCs in the developing neocortex. DOI: http://dx.doi.org/10.7554/eLife.11324.001 PMID:26883496

  9. Mouse Fkbp8 activity is required to inhibit cell death and establish dorso-ventral patterning in the posterior neural tube.

    PubMed

    Wong, Rebecca Lee Yean; Wlodarczyk, Bogdan J; Min, Kyung Soo; Scott, Melissa L; Kartiko, Susan; Yu, Wei; Merriweather, Michelle Y; Vogel, Peter; Zambrowicz, Brian P; Finnell, Richard H

    2008-02-15

    Neural tube defects (NTDs) are birth defects that can be disabling or lethal and are second in their prevalence after cardiac defects among major human congenital malformations. Spina bifida is a NTD where the spinal cord is dysplastic, and the overlying spinal column is absent. At present, the molecular mechanisms underlying the spinal bifida development are largely unknown. In this study, we present a Fkbp8 mouse mutant that has an isolated and completely penetrant spina bifida, which is folate- and inositol-resistant. Fkbp8 mutants are not embryo lethal, but they display striking features of human spina bifida, including a dysplastic spinal cord, open neural canal and disability. The loss of Fkbp8 leads to increased apoptosis in the posterior neural tube, demonstrating that in vivo FKBP8 inhibits cell death. Gene expression analysis of Fkbp8 mutants revealed a perturbation of expression of neural tube patterning genes, suggesting that endogenous FKBP8 activity establishes dorso-ventral patterning of the neural tube. These studies demonstrate that Fkbp8 is not important for embryo survival, but is essential for spinal neural tube patterning, and to block apoptosis, in the developing neural tube. The mutant Fkbp8 allele is a new experimental model which will be useful in dissecting the pathogenesis of spinal NTDs, and enhance our understanding of the etiology of human NTDs. PMID:18003640

  10. Overexpression of CD44 in Neural Precursor Cells Improves Trans- Endothelial Migration and Facilitates Their Invasion of Perivascular Tissues In Vivo

    PubMed Central

    Deboux, Cyrille; Ladraa, Sophia; Cazaubon, Sylvie; Ghribi-Mallah, Siham; Weiss, Nicolas; Chaverot, Nathalie; Couraud, Pierre Olivier; Evercooren, Anne Baron-Van

    2013-01-01

    Neural precursor (NPC) based therapies are used to restore neurons or oligodendrocytes and/or provide neuroprotection in a large variety of neurological diseases. In multiple sclerosis models, intravenously (i.v) -delivered NPCs reduced clinical signs via immunomodulation. We demonstrated recently that NPCs were able to cross cerebral endothelial cells in vitro and that the multifunctional signalling molecule, CD44 involved in trans-endothelial migration of lymphocytes to sites of inflammation, plays a crucial role in extravasation of syngeneic NPCs. In view of the role of CD44 in NPCs trans-endothelial migration in vitro, we questioned presently the benefit of CD44 overexpression by NPCs in vitro and in vivo, in EAE mice. We show that overexpression of CD44 by NPCs enhanced over 2 folds their trans-endothelial migration in vitro, without impinging on the proliferation or differentiation potential of the transduced cells. Moreover, CD44 overexpression by NPCs improved significantly their elongation, spreading and number of filopodia over the extracellular matrix protein laminin in vitro. We then tested the effect of CD44 overexpression after i.v. delivery in the tail vein of EAE mice. CD44 overexpression was functional in vivo as it accelerated trans-endothelial migration and facilitated invasion of HA expressing perivascular sites. These in vitro and in vivo data suggest that CD44 may be crucial not only for NPC crossing the endothelial layer but also for facilitating invasion of extravascular tissues. PMID:23468987

  11. Modulation of the Innate Immune Response by Human Neural Precursors Prevails over Oligodendrocyte Progenitor Remyelination to Rescue a Severe Model of Pelizaeus-Merzbacher Disease.

    PubMed

    Marteyn, Antoine; Sarrazin, Nadège; Yan, Jun; Bachelin, Corinne; Deboux, Cyrille; Santin, Mathieu D; Gressens, Pierre; Zujovic, Violetta; Baron-Van Evercooren, Anne

    2016-04-01

    Pelizaeus-Merzbacher disease (PMD) results from an X-linked misexpression of proteolipid protein 1 (PLP1). This leukodystrophy causes severe hypomyelination with progressive inflammation, leading to neurological dysfunctions and shortened life expectancy. While no cure exists for PMD, experimental cell-based therapy in the dysmyelinated shiverer model suggested that human oligodendrocyte progenitor cells (hOPCs) or human neural precursor cells (hNPCs) are promising candidates to treat myelinopathies. However, the fate and restorative advantages of human NPCs/OPCs in a relevant model of PMD has not yet been addressed. Using a model of Plp1 overexpression, resulting in demyelination with progressive inflammation, we compared side-by-side the therapeutic benefits of intracerebrally grafted hNPCs and hOPCs. Our findings reveal equal integration of the donor cells within presumptive white matter tracks. While the onset of exogenous remyelination was earlier in hOPCs-grafted mice than in hNPC-grafted mice, extended lifespan occurred only in hNPCs-grafted animals. This improved survival was correlated with reduced neuroinflammation (microglial and astrocytosis loads) and microglia polarization toward M2-like phenotype followed by remyelination. Thus modulation of neuroinflammation combined with myelin restoration is crucial to prevent PMD pathology progression and ensure successful rescue of PMD mice. These findings should help to design novel therapeutic strategies combining immunomodulation and stem/progenitor cell-based therapy for disorders associating hypomyelination with inflammation as observed in PMD. Stem Cells 2016;34:984-996. PMID:26676415

  12. BDNF Increases Survival and Neuronal Differentiation of Human Neural Precursor Cells Cotransplanted with a Nanofiber Gel to the Auditory Nerve in a Rat Model of Neuronal Damage

    PubMed Central

    Jiao, Yu; Palmgren, Björn; Novozhilova, Ekaterina; Englund Johansson, Ulrica; Spieles-Engemann, Anne L.; Kale, Ajay; Stupp, Samuel I.; Olivius, Petri

    2014-01-01

    Objectives. To study possible nerve regeneration of a damaged auditory nerve by the use of stem cell transplantation. Methods. We transplanted HNPCs to the rat AN trunk by the internal auditory meatus (IAM). Furthermore, we studied if addition of BDNF affects survival and phenotypic differentiation of the grafted HNPCs. A bioactive nanofiber gel (PA gel), in selected groups mixed with BDNF, was applied close to the implanted cells. Before transplantation, all rats had been deafened by a round window niche application of β-bungarotoxin. This neurotoxin causes a selective toxic destruction of the AN while keeping the hair cells intact. Results. Overall, HNPCs survived well for up to six weeks in all groups. However, transplants receiving the BDNF-containing PA gel demonstrated significantly higher numbers of HNPCs and neuronal differentiation. At six weeks, a majority of the HNPCs had migrated into the brain stem and differentiated. Differentiated human cells as well as neurites were observed in the vicinity of the cochlear nucleus. Conclusion. Our results indicate that human neural precursor cells (HNPC) integration with host tissue benefits from additional brain derived neurotrophic factor (BDNF) treatment and that these cells appear to be good candidates for further regenerative studies on the auditory nerve (AN). PMID:25243135

  13. The Methyl-CpG Binding Proteins Mecp2, Mbd2 and Kaiso Are Dispensable for Mouse Embryogenesis, but Play a Redundant Function in Neural Differentiation

    PubMed Central

    Martín Caballero, Isabel; Hansen, Janne; Leaford, Donna; Pollard, Steven; Hendrich, Brian D.

    2009-01-01

    Background The precise molecular changes that occur when a neural stem (NS) cell switches from a programme of self-renewal to commit towards a specific lineage are not currently well understood. However it is clear that control of gene expression plays an important role in this process. DNA methylation, a mark of transcriptionally silent chromatin, has similarly been shown to play important roles in neural cell fate commitment in vivo. While DNA methylation is known to play important roles in neural specification during embryonic development, no such role has been shown for any of the methyl-CpG binding proteins (Mecps) in mice. Methodology/Principal Findings To explore the role of DNA methylation in neural cell fate decisions, we have investigated the function of Mecps in mouse development and in neural stem cell derivation, maintenance, and differentiation. In order to test whether the absence of phenotype in singly-mutant animals could be due to functional redundancy between Mecps, we created mice and neural stem cells simultaneously lacking Mecp2, Mbd2 and Zbtb33. No evidence for functional redundancy between these genes in embryonic development or in the derivation or maintenance of neural stem cells in culture was detectable. However evidence for a defect in neuronal commitment of triple knockout NS cells was found. Conclusions/Significance Although DNA methylation is indispensable for mammalian embryonic development, we show that simultaneous deficiency of three methyl-CpG binding proteins genes is compatible with apparently normal mouse embryogenesis. Nevertheless, we provide genetic evidence for redundancy of function between methyl-CpG binding proteins in postnatal mice. PMID:19177165

  14. Promotion of Cortical Neurogenesis from the Neural Stem Cells in the Adult Mouse Subcallosal Zone.

    PubMed

    Kim, Joo Yeon; Choi, Kyuhyun; Shaker, Mohammed R; Lee, Ju-Hyun; Lee, Boram; Lee, Eunsoo; Park, Jae-Yong; Lim, Mi-Sun; Park, Chang-Hwan; Shin, Ki Soon; Kim, Hyun; Geum, Dongho; Sun, Woong

    2016-04-01

    Neurogenesis occurs spontaneously in the subventricular zone (SVZ) of the lateral ventricle in adult rodent brain, but it has long been debated whether there is sufficient adult neurogenesis in human SVZ. Subcallosal zone (SCZ), a posterior continuum of SVZ closely associated with posterior regions of cortical white matter, has also been reported to contain adult neural stem cells (aNSCs) in both rodents and humans. However, little is known whether SCZ-derived aNSC (SCZ-aNSCs) can produce cortical neurons following brain injury. We found that SCZ-aNSCs exhibited limited neuronal differentiation potential in culture and after transplantation in mice. Neuroblasts derived from SCZ initially migrated toward injured cortex regions following brain injury, but later exhibited apoptosis. Overexpression of anti-apoptotic bcl-xL in the SCZ by retroviral infection rescued neuroblasts from cell death in the injured cortex, but neuronal maturation was still limited, resulting in atrophy. In combination with Bcl-xL, infusion of brain-derived neurotropic factor rescued atrophy, and importantly, a subset of such SCZ-aNSCs differentiated and attained morphological and physiological characteristics of mature, excitatory neurons. These results suggest that the combination of anti-apoptotic and neurotrophic factors might enable the use of aNSCs derived from the SCZ in cortical neurogenesis for neural replacement therapy. Stem Cells 2016;34:888-901. PMID:26701067

  15. Neuronal Store-Operated Calcium Entry and Mushroom Spine Loss in Amyloid Precursor Protein Knock-In Mouse Model of Alzheimer's Disease

    PubMed Central

    Zhang, Hua; Wu, Lili; Pchitskaya, Ekaterina; Zakharova, Olga; Saito, Takashi; Saido, Takaomi

    2015-01-01

    Alzheimer's disease (AD) is the most common reason for elderly dementia in the world. We proposed that memory loss in AD is related to destabilization of mushroom postsynaptic spines involved in long-term memory storage. We demonstrated previously that stromal interaction molecule 2 (STIM2)-regulated neuronal store-operated calcium entry (nSOC) in postsynaptic spines play a key role in stability of mushroom spines by maintaining activity of synaptic Ca2+/calmodulin kinase II (CaMKII). Furthermore, we demonstrated previously that the STIM2–nSOC–CaMKII pathway is downregulated in presenilin 1 M146V knock-in (PS1–M146V KI) mouse model of AD, leading to loss of hippocampal mushroom spines in this model. In the present study, we demonstrate that hippocampal mushroom postsynaptic spines are also lost in amyloid precursor protein knock-in (APPKI) mouse model of AD. We demonstrated that loss of mushroom spines occurs as a result of accumulation of extracellular β-amyloid 42 in APPKI culture media. Our results indicate that extracellular Aβ42 acts by overactivating mGluR5 receptor in APPKI neurons, leading to elevated Ca2+ levels in endoplasmic reticulum, compensatory downregulation of STIM2 expression, impaired synaptic nSOC, and reduced CaMKII activity. Pharmacological inhibition of mGluR5 or overexpression of STIM2 rescued synaptic nSOC and prevented mushroom spine loss in APPKI hippocampal neurons. Our results indicate that downregulation of synaptic STIM2–nSOC–CaMKII pathway causes loss of mushroom synaptic spines in both presenilin and APPKI mouse models of AD. We propose that modulators/activators of this pathway may have a potential therapeutic value for treatment of memory loss in AD. SIGNIFICANCE STATEMENT A direct connection between amyloid-induced synaptic mushroom spine loss and neuronal store-operated calcium entry pathway is shown. These results provide strong support for the calcium hypothesis of neurodegeneration and further validate the

  16. BarTeL, a Genetically Versatile, Bioluminescent and Granule Neuron Precursor-Targeted Mouse Model for Medulloblastoma

    PubMed Central

    Mahdi, Min Y.; Gonzalez-Gomez, Ignacio; Asgharzadeh, Shahab; D’Apuzzo, Massimo; Erdreich-Epstein, Anat; Moats, Rex A.

    2016-01-01

    Medulloblastomas are the most common malignant pediatric brain tumor and have been divided into four major molecular subgroups. Animal models that mimic the principal molecular aberrations of these subgroups will be important tools for preclinical studies and allow greater understanding of medulloblastoma biology. We report a new transgenic model of medulloblastoma that possesses a unique combination of desirable characteristics including, among others, the ability to incorporate multiple and variable genes of choice and to produce bioluminescent tumors from a limited number of somatic cells within a normal cellular environment. This model, termed BarTeL, utilizes a Barhl1 homeobox gene promoter to target expression of a bicistronic transgene encoding both the avian retroviral receptor TVA and an eGFP-Luciferase fusion protein to neonatal cerebellar granule neuron precursor (cGNP) cells, which are cells of origin for the sonic hedgehog (SHH) subgroup of human medulloblastomas. The Barhl1 promoter-driven transgene is expressed strongly in mammalian cGNPs and weakly or not at all in mature granule neurons. We efficiently induced bioluminescent medulloblastomas expressing eGFP-luciferase in BarTeL mice by infection of a limited number of somatic cGNPs with avian retroviral vectors encoding the active N-terminal fragment of SHH and a stabilized MYCN mutant. Detection and quantification of the increasing bioluminescence of growing tumors in young BarTeL mice was facilitated by the declining bioluminescence of their uninfected maturing cGNPs. Inclusion of eGFP in the transgene allowed enriched sorting of cGNPs from neonatal cerebella. Use of a single bicistronic avian vector simultaneously expressing both Shh and Mycn oncogenes increased the medulloblastoma incidence and aggressiveness compared to mixed virus infections. Bioluminescent tumors could also be produced by ex vivo transduction of neonatal BarTeL cerebellar cells by avian retroviruses and subsequent

  17. BarTeL, a Genetically Versatile, Bioluminescent and Granule Neuron Precursor-Targeted Mouse Model for Medulloblastoma.

    PubMed

    Shackleford, Gregory M; Shi, Xiang-He; Swanson, Kimberly S; Mahdi, Min Y; Gonzalez-Gomez, Ignacio; Asgharzadeh, Shahab; D'Apuzzo, Massimo; Erdreich-Epstein, Anat; Moats, Rex A

    2016-01-01

    Medulloblastomas are the most common malignant pediatric brain tumor and have been divided into four major molecular subgroups. Animal models that mimic the principal molecular aberrations of these subgroups will be important tools for preclinical studies and allow greater understanding of medulloblastoma biology. We report a new transgenic model of medulloblastoma that possesses a unique combination of desirable characteristics including, among others, the ability to incorporate multiple and variable genes of choice and to produce bioluminescent tumors from a limited number of somatic cells within a normal cellular environment. This model, termed BarTeL, utilizes a Barhl1 homeobox gene promoter to target expression of a bicistronic transgene encoding both the avian retroviral receptor TVA and an eGFP-Luciferase fusion protein to neonatal cerebellar granule neuron precursor (cGNP) cells, which are cells of origin for the sonic hedgehog (SHH) subgroup of human medulloblastomas. The Barhl1 promoter-driven transgene is expressed strongly in mammalian cGNPs and weakly or not at all in mature granule neurons. We efficiently induced bioluminescent medulloblastomas expressing eGFP-luciferase in BarTeL mice by infection of a limited number of somatic cGNPs with avian retroviral vectors encoding the active N-terminal fragment of SHH and a stabilized MYCN mutant. Detection and quantification of the increasing bioluminescence of growing tumors in young BarTeL mice was facilitated by the declining bioluminescence of their uninfected maturing cGNPs. Inclusion of eGFP in the transgene allowed enriched sorting of cGNPs from neonatal cerebella. Use of a single bicistronic avian vector simultaneously expressing both Shh and Mycn oncogenes increased the medulloblastoma incidence and aggressiveness compared to mixed virus infections. Bioluminescent tumors could also be produced by ex vivo transduction of neonatal BarTeL cerebellar cells by avian retroviruses and subsequent

  18. Mouse pre-immunocytes as non-proliferating multipotent precursors of macrophages, interferon-producing cells, CD8alpha(+) and CD8alpha(-) dendritic cells.

    PubMed

    Bruno, L; Seidl, T; Lanzavecchia, A

    2001-11-01

    In this study we characterize in mouse bone marrow and peripheral blood a homogeneous cell subset expressing Ly6C, CD31 and CD11c, that can give rise to multiple cell types involved in the immune response. Under the aegis of M-CSF or GM-CSF these cells rapidly differentiate without division to either macrophages or immature dendritic cells, which can be further induced to mature by LPS stimulation. In fetal thymic organ cultures the same cells generate both CD8alpha(+) and CD8alpha(-) dendritic cells in comparable proportion as found in normal thymus. The Ly6C(+), CD31(+) and CD11c(+) cells express not only TLR2 and TLR4, which are characteristic of myeloid dendritic cells, but also TLR7 and TLR9, which conversely are characteristic of human interferon-producing cells. Moreover, following stimulation with influenza virus, they rapidly express high levels of IFN-alpha mRNA. Finally these precursors are increased in bone marrow and peripheral blood during systemic inflammation. These cells are defined as "pre-immunocytes" to underline the fact that they serve in a flexible fashion multiple, and often divergent, functions required for the immune response to pathogens. PMID:11745359

  19. Scutellarin Alleviates Behavioral Deficits in a Mouse Model of Multiple Sclerosis, Possibly Through Protecting Neural Stem Cells.

    PubMed

    Wang, Wei-Wei; Lu, Lin; Bao, Tian-Hao; Zhang, Hong-Miao; Yuan, Jing; Miao, Wei; Wang, Shu-Fen; Xiao, Zhi-Cheng

    2016-02-01

    Scutellarin, a flavonoid extracted from an herbal medication (Erigeron breviscapus Hand-Mazz), has been shown to protect neurons against damage and to promote neurogenesis, and thus has therapeutic potential in the treatment of a variety of neurodegenerative diseases. Since neural stem cells (NSCs) could differentiate into myelin-producing oligodendrocytes, we speculate that scutellarin could also be used to treat multiple sclerosis (MS). In the current study, we examined potential effects of scutellarin using a mouse model of MS. Briefly, adult C57BL/6 mice exposed to cuprizone (8 mg/day through diet, for 6 consecutive weeks) randomly received scutellarin (50 mg/kg/day) or vehicle for 10 consecutive days. In the scutellarin-treated group, rotarod testing at the end of the treatment showed significant improvement of motor function (increased time to fall); myelin basic protein (MBP) staining of the corpus callosum revealed decreased demyelination; TUNEL staining followed by Nestin or Sox2 staining revealed increased number of NSCs and decreased rate of NSC apoptosis in the subventricular zone (SVZ) of the lateral ventricles (LV). In a series of experiments using cultured NSCs subjected to cuprizone injury, we confirmed the protective effects of scutellarin. At 30 μM, scutellarin increased the commitment of NSCs to the oligodendrocyte and neuronal lineages, as evidenced by NG2 chondroitin sulfate proteoglycan (NG2) and doublecortin (DCX) staining. Differentiation into astrocytes (as revealed by glial fibrillary acidic protein (GFAP) staining) was decreased. Maturation of the NSCs committed to the oligodendrocyte lineage, as evidenced by oligodendrocyte marker O4 antibody (O4) staining and MBP staining, was also promoted by scutellarin. Further analysis revealed that scutellarin might suppress the phosphorylation of p38 in cuprizone-induced NSCs. In summary, scutellarin could alleviate motor deficits in a mouse model for MS, possibly by inhibiting NSC apoptosis and

  20. Brevetoxin-Induced Neural Insult in the Retrosplenial Cortex of Mouse Brain

    PubMed Central

    Yan, Xiuzhen; Benson, Janet M.; Gomez, Andrea P.; Baden, Daniel G.; Murray, Thomas F.

    2008-01-01

    Brevetoxins (polyether breve toxins; PbTx) are polyether neurotoxins produced by the marine dinoflagellate Karenia brevis, an organism associated with red tide blooms in the Gulf of Mexico and along the Atlantic coast from Florida to North Carolina. Brevetoxin-3 (PbTx-3) is a major component of the array of brevetoxins found in marine aerosols measured along red tide affected beaches. Humans exposed to aerosolized brevetoxins for short periods of time often suffer a variety of adverse health effects. It was consequently of interest to assess the potential for aerosolized brevetoxin to produce a neurotoxic response. Female BALB/c mice were exposed nose-only for 2 consecutive days to PbTx-3 aerosol, with a 2-h exposure on the first day and a 4-h exposure on the second day. The average PbTx-3 exposure concentrations on days 1 and 2 were 312 ± 113 μg brevetoxin 3/m3 and 278± 24μg brevetoxin 3/m3, respectively. The brevetoxin-containing aerosol had a mass median aerodynamic diameter of 0.92μm with a geometric standard deviation of 1.38. Coronal sections of mouse brains were evaluated for neuronal damage using both silver and Fluoro-Jade B staining to identify degenerating neuronal elements. PbTx-3 inhalation exposure produced neuronal degeneration in the posterior cingu-late/retrosplenial cortex of mice as evidenced by silver-positive degenerating neurons in this region. No staining was found in other regions of the PBTx-3-exposed mouse brains or in brains of control, sham-exposed mice. The existence of a neurotoxic insult in PbTx-3-exposed mice was confirmed using Fluoro-Jade B to label degenerating neurons. Fluro-Jade-positive neurons were observed in the retrosplenial cortex of PBTx-3 exposed, but not control, mice. These results suggest that subacute exposure to PbTx-3 for 2 days is sufficient to induce neuronal degeneration in a discrete region of the mouse cerebral cortex. PMID:17043031

  1. Inositol prevents folate-resistant neural tube defects in the mouse.

    PubMed

    Greene, N D; Copp, A J

    1997-01-01

    Clinical trials demonstrate that up to 70% of neural tube defects (NTDs) can be prevented by folic acid supplementation in early pregnancy, whereas the remaining NTDs are resistant to folate. Here, we show that a second vitamin, myo-inositol, is capable of significantly reducing the incidence of spinal NTDs in curly tail mice, a genetic model of folate-resistant NTDs. Inositol increases flux through the inositol/lipid cycle, stimulating protein kinase C activity and upregulating expression of retinoic acid receptor beta, specifically in the caudal portion of the embryonic hindgut. This reduces the delay in closure of the posterior neuropore, the embryonic defect that is known to lead directly to spina bifida in curly tail embryos. Our findings reveal a molecular pathway of NTD prevention and suggest the possible efficacy of combined treatment with folate and inositol in overcoming the majority of human NTDs. PMID:8986742

  2. From neural to genetic substrates of panic disorder: Insights from human and mouse studies.

    PubMed

    Santos, Mónica; D'Amico, Davide; Dierssen, Mara

    2015-07-15

    Fear is an ancestral emotion, an intrinsic defensive response present in every organism. Although fear is an evolutionarily advantageous emotion, under certain pathologies such as panic disorder it might become exaggerated and non-adaptive. Clinical and preclinical work pinpoints that changes in cognitive processes, such as perception and interpretation of environmental stimuli that rely on brain regions responsible for high-level function, are essential for the development of fear-related disorders. This review focuses on the involvement of cognitive function to fear circuitry disorders. Moreover, we address how animal models are contributing to understand the involvement of human candidate genes to pathological fear and helping achieve progress in this field. Multidisciplinary approaches that integrate human genetic findings with state of the art genetic mouse models will allow to elucidate the mechanisms underlying pathology and to develop new strategies for therapeutic targeting. PMID:25818748

  3. Return to quiescence of mouse neural stem cells by degradation of a proactivation protein.

    PubMed

    Urbán, Noelia; van den Berg, Debbie L C; Forget, Antoine; Andersen, Jimena; Demmers, Jeroen A A; Hunt, Charles; Ayrault, Olivier; Guillemot, François

    2016-07-15

    Quiescence is essential for long-term maintenance of adult stem cells. Niche signals regulate the transit of stem cells from dormant to activated states. Here, we show that the E3-ubiquitin ligase Huwe1 (HECT, UBA, and WWE domain-containing 1) is required for proliferating stem cells of the adult mouse hippocampus to return to quiescence. Huwe1 destabilizes proactivation protein Ascl1 (achaete-scute family bHLH transcription factor 1) in proliferating hippocampal stem cells, which prevents accumulation of cyclin Ds and promotes the return to a resting state. When stem cells fail to return to quiescence, the proliferative stem cell pool becomes depleted. Thus, long-term maintenance of hippocampal neurogenesis depends on the return of stem cells to a transient quiescent state through the rapid degradation of a key proactivation factor. PMID:27418510

  4. 532 nm Low-Power Laser Irradiation Facilitates the Migration of GABAergic Neural Stem/Progenitor Cells in Mouse Neocortex

    PubMed Central

    Fukuzaki, Yumi; Shin, Hyeryun; Kawai, Hideki D.; Yamanoha, Banri; Kogure, Shinichi

    2015-01-01

    Background and Objective Accumulating evidence has shown that low-power laser irradiation (LLI) affects cell proliferation and survival, but little is known about LLI effects on neural stem/progenitor cells (NSPCs). Here we investigate whether transcranial 532 nm LLI affects NSPCs in adult murine neocortex and in neurospheres from embryonic mice. Study Design/Materials and Methods We applied 532 nm LLI (Nd:YVO4, CW, 60 mW) on neocortical surface via cranium in adult mice and on cultured cells from embryonic mouse brains in vitro to investigate the proliferation and migration of NSPCs and Akt expression using immunohistochemical assays and Western blotting techniques. Results In vivo experiments demonstrated that 532 nm LLI significantly facilitated the migration of GABAergic NSPCs that were induced to proliferate in layer 1 by mild ischemia. In vitro experiments using GABAergic NSPCs derived from embryonic day 14 ganglionic eminence demonstrated that 532 nm LLI for 60 min promoted the migration of GAD67-immunopositive NSPCs with a significant increase of Akt expression. Meanwhile, the LLI induced proliferation, but not migration, of NSPCs that give rise to excitatory neurons. Conclusion It is concluded that 532 nm LLI promoted the migration of GABAergic NSPCs into deeper layers of the neocortex in vivo by elevating Akt expression. PMID:25919297

  5. Testing for genetic associations in a spina bifida population: analysis of the HOX gene family and human candidate gene regions implicated by mouse models of neural tube defects.

    PubMed

    Volcik, K A; Blanton, S H; Kruzel, M C; Townsend, I T; Tyerman, G H; Mier, R J; Northrup, H

    2002-07-01

    Neural tube defects (NTDs) are among the most common severely disabling birth defects in the United States, affecting approximately 1-2 of every 1,000 live births. The etiology of NTDs is multifactorial, involving the combined action of both genetic and environmental factors. HOX genes play a central role in establishing the initial body plan by providing positional information along the anterior-posterior body and limb axis and have been implicated in neural tube closure. There are many mouse models that exhibit both naturally occurring NTDs in various mouse strains as well as NTDs that have been created by "knocking out" various genes. A nonparametric linkage method, the transmission disequilibrium test (TDT), was utilized to test the HOX gene family and human equivalents of genes (when known) or the syntenic region in humans to those in mouse models which could play a role in the formation of NTDs. DNA from 459 spina bifida (SB) affected individuals and their parents was tested for linkage and association utilizing polymorphic markers from within or very close to the HOXA, HOXB, HOXC, and HOXD genes as well as from within the genes/gene regions of eight mouse models that exhibit NTDs. No significant findings were obtained for the tested markers. PMID:12116226

  6. A mutation in the tuft mouse disrupts TET1 activity and alters the expression of genes that are crucial for neural tube closure.

    PubMed

    Fong, Keith S K; Hufnagel, Robert B; Khadka, Vedbar S; Corley, Michael J; Maunakea, Alika K; Fogelgren, Ben; Ahmed, Zubair M; Lozanoff, Scott

    2016-05-01

    Genetic variations affecting neural tube closure along the head result in malformations of the face and brain. Neural tube defects (NTDs) are among the most common birth defects in humans. We previously reported a mouse mutant called tuft that arose spontaneously in our wild-type 3H1 colony. Adult tuft mice present midline craniofacial malformations with or without an anterior cephalocele. In addition, affected embryos presented neural tube closure defects resulting in insufficient closure of the anterior neuropore or exencephaly. Here, through whole-genome sequencing, we identified a nonsense mutation in the Tet1 gene, which encodes a methylcytosine dioxygenase (TET1), co-segregating with the tuft phenotype. This mutation resulted in premature termination that disrupts the catalytic domain that is involved in the demethylation of cytosine. We detected a significant loss of TET enzyme activity in the heads of tuft embryos that were homozygous for the mutation and had NTDs. RNA-Seq transcriptome analysis indicated that multiple gene pathways associated with neural tube closure were dysregulated in tuft embryo heads. Among them, the expressions of Cecr2, Epha7 and Grhl2 were significantly reduced in some embryos presenting neural tube closure defects, whereas one or more components of the non-canonical WNT signaling pathway mediating planar cell polarity and convergent extension were affected in others. We further show that the recombinant mutant TET1 protein was capable of entering the nucleus and affected the expression of endogenous Grhl2 in IMCD-3 (inner medullary collecting duct) cells. These results indicate that TET1 is an epigenetic determinant for regulating genes that are crucial to closure of the anterior neural tube and its mutation has implications to craniofacial development, as presented by the tuft mouse. PMID:26989192

  7. A mutation in the tuft mouse disrupts TET1 activity and alters the expression of genes that are crucial for neural tube closure

    PubMed Central

    Khadka, Vedbar S.; Corley, Michael J.; Maunakea, Alika K.; Fogelgren, Ben; Ahmed, Zubair M.; Lozanoff, Scott

    2016-01-01

    ABSTRACT Genetic variations affecting neural tube closure along the head result in malformations of the face and brain. Neural tube defects (NTDs) are among the most common birth defects in humans. We previously reported a mouse mutant called tuft that arose spontaneously in our wild-type 3H1 colony. Adult tuft mice present midline craniofacial malformations with or without an anterior cephalocele. In addition, affected embryos presented neural tube closure defects resulting in insufficient closure of the anterior neuropore or exencephaly. Here, through whole-genome sequencing, we identified a nonsense mutation in the Tet1 gene, which encodes a methylcytosine dioxygenase (TET1), co-segregating with the tuft phenotype. This mutation resulted in premature termination that disrupts the catalytic domain that is involved in the demethylation of cytosine. We detected a significant loss of TET enzyme activity in the heads of tuft embryos that were homozygous for the mutation and had NTDs. RNA-Seq transcriptome analysis indicated that multiple gene pathways associated with neural tube closure were dysregulated in tuft embryo heads. Among them, the expressions of Cecr2, Epha7 and Grhl2 were significantly reduced in some embryos presenting neural tube closure defects, whereas one or more components of the non-canonical WNT signaling pathway mediating planar cell polarity and convergent extension were affected in others. We further show that the recombinant mutant TET1 protein was capable of entering the nucleus and affected the expression of endogenous Grhl2 in IMCD-3 (inner medullary collecting duct) cells. These results indicate that TET1 is an epigenetic determinant for regulating genes that are crucial to closure of the anterior neural tube and its mutation has implications to craniofacial development, as presented by the tuft mouse. PMID:26989192

  8. Pioglitazone significantly prevented decreased rate of neural differentiation of mouse embryonic stem cells which was reduced by Pex11β knock-down.

    PubMed

    Esmaeili, M; Ghaedi, K; Shoaraye Nejati, A; Nematollahi, M; Shiralyian, H; Nasr-Esfahani, M H

    2016-01-15

    Peroxisomes constitute special cellular organelles which display a variety of metabolic functions including fatty acid oxidation and free radical elimination. Abundance of these flexible organelles varies in response to different environmental stimuli. It has been demonstrated that PEX11β, a peroxisomal membrane elongation factor, is involved in the regulation of size, shape and number of peroxisomes. To investigate the role of PEX11β in neural differentiation of mouse embryonic stem cells (mESCs), we generated a stably transduced mESCs line that derives the expression of a short hairpin RNA against Pex11β gene following doxycycline (Dox) induction. Knock-down of Pex11β, during neural differentiation, significantly reduced the expression of neural progenitor cells and mature neuronal markers (p<0.05) indicating that decreased expression of PEX11β suppresses neuronal maturation. Additionally, mRNA levels of other peroxisome-related genes such as PMP70, Pex11α, Catalase, Pex19 and Pex5 were also significantly reduced by Pex11β knock-down (p<0.05). Interestingly, pretreatment of transduced mESCs with peroxisome proliferator-activated receptor γ agonist (pioglitazone (Pio)) ameliorated the inhibitory effects of Pex11β knock down on neural differentiation. Pio also significantly (p<0.05) increased the expression of neural progenitor and mature neuronal markers besides the expression of peroxisomal genes in transduced mESC. Results elucidated the importance of Pex11β expression in neural differentiation of mESCs, thereby highlighting the essential role of peroxisomes in mammalian neural differentiation. The observation that Pio recovered peroxisomal function and improved neural differentiation of Pex11β knocked-down mESCs, proposes a potential new pharmacological implication of Pio for neurogenesis in patients with peroxisomal defects. PMID:26562432

  9. Phenytoin enhances the phosphorylation of epidermal growth factor receptor and fibroblast growth factor receptor in the subventricular zone and promotes the proliferation of neural precursor cells and oligodendrocyte differentiation.

    PubMed

    Galvez-Contreras, Alma Y; Gonzalez-Castaneda, Rocio E; Campos-Ordonez, Tania; Luquin, Sonia; Gonzalez-Perez, Oscar

    2016-01-01

    Phenytoin is a widely used antiepileptic drug that induces cell proliferation in several tissues, such as heart, bone, skin, oral mucosa and neural precursors. Some of these effects are mediated via fibroblast growth factor receptor (FGFR) and epidermal growth factor receptor (EGFR). These receptors are strongly expressed in the adult ventricular-subventricular zone (V-SVZ), the main neurogenic niche in the adult brain. The aim of this study was to determine the cell lineage and cell fate of V-SVZ neural progenitors expanded by phenytoin, as well as the effects of this drug on EGFR/FGFR phosphorylation. Male BALB/C mice received 10 mg/kg phenytoin by oral cannula for 30 days. We analysed the proliferation of V-SVZ neural progenitors by immunohistochemistry and western blot. Our findings indicate that phenytoin enhanced twofold the phosphorylation of EGFR and FGFR in the V-SVZ, increased the number of bromodeoxyuridine (BrdU)+/Sox2+ and BrdU+/doublecortin+ cells in the V-SVZ, and expanded the population of Olig2-expressing cells around the lateral ventricles. After phenytoin removal, a large number of BrdU+/Receptor interacting protein (RIP)+ cells were observed in the olfactory bulb. In conclusion, phenytoin enhanced the phosphorylation of FGFR and EGFR, and promoted the expression of neural precursor markers in the V-SVZ. In parallel, the number of oligodendrocytes increased significantly after phenytoin removal. PMID:26370587

  10. Heparan Sulfate Expression in the Neural Crest is Essential for Mouse Cardiogenesis

    PubMed Central

    Pan, Yi; Carbe, Christian; Pickhinke, Ute; Kupich, Sabine; Ohlig, Stefanie; Frye, Maike; Seelige, Ruth; Pallerla, Srinivas R.; Moon, Anne M.; Lawrence, Roger; Esko, Jeffrey D.; Zhang, Xin; Grobe, Kay

    2015-01-01

    Impaired heparan sulfate (HS) synthesis in vertebrate development causes complex malformations due to the functional disruption of multiple HS-binding growth factors and morphogens. Here, we report developmental heart defects in mice bearing a targeted disruption of the HS-generating enzyme GlcNAc N-Deacetylase/GlcN N-Sulfotransferase 1 (NDST1), including ventricular septal defects (VSD), persistent truncus arteriosus (PTA), double outlet right ventricle (DORV), and retroesophageal right subclavian artery (RERSC). These defects closely resemble cardiac anomalies observed in mice made deficient in the cardiogenic regulator fibroblast growth factor 8 (FGF8). Consistent with this, we show that HS-dependent FGF8/FGF-receptor2C assembly and FGF8-dependent ERK-phosphorylation are strongly reduced in NDST1−/− embryonic cells and tissues. Moreover, WNT1-Cre/LoxP-mediated conditional targeting of NDST function in neural crest cells (NCCs) revealed that their impaired HS-dependent development contributes strongly to the observed cardiac defects. These findings raise the possibility that defects in HS biosynthesis may contribute to congenital heart defects in humans that represent the most common type of birth defect. PMID:24200809

  11. A Neural Circuit That Controls Cortical State, Plasticity, and the Gain of Sensory Responses in Mouse

    PubMed Central

    Stryker, Michael P.

    2015-01-01

    Neurons in the visual cortex were first found to be exquisitely selective for particular properties of visual stimuli in anesthetized animals, including mice. Studies of alert mice in an apparatus that allowed them to stand or run revealed that locomotion causes a change in cortical state that dramatically increases the magnitude of responses in neurons of the visual cortex without altering selectivity, effectively changing the gain of sensory responses. Locomotion also dramatically enhances adult plasticity in the recovery from long-term visual deprivation. We have studied the elements and operation of the neural circuit responsible for the enhancement of activity and shown that it enhances plasticity even in mice not free to run. The circuit consists of projections ascending from the midbrain locomotor region (MLR) to the basal forebrain, activating cholinergic and perhaps other projections to excite inhibitory interneurons expressing vasoactive intestinal peptide (VIP) in the visual cortex. VIP cells activated by locomotion inhibit interneurons that express somatostatin (SST), thereby disinhibiting the excitatory principal neurons and allowing them to respond more strongly to effective visual stimuli. These findings reveal in alert animals how the ascending reticular activating system described in anesthetized animals 50 years ago operates to control cortical state. PMID:25948638

  12. [Macrophages promote the migration of neural stem cells into mouse spinal cord injury site].

    PubMed

    Cheng, Zhijian; Zhu, Wen; Li, Haopeng; He, Xijing

    2016-09-01

    Objective To explore the role of macrophages in the migration of neural stem cells (NSCs) in vivo and in vitro . Methods NSCs with green fluorescent protein (GFP) were isolated from GFP transgenic mice and the immunofluorescence cytochemical staining of nestin was used to identify NSCs. After spinal cord injury was induced, the tissue level of macrophage chemotactic protein-1 (MCP-1) mRNA was detected using quantitative real time PCR. The migration of GFP-NSCs was investigated 1 week after GFP-NSCs were injected into both sides of the damaged area. The effect of macrophage on the migration of NSCs in vitro was tested by Transwell(TM) system and the content of MCP-1 was detected by ELISA. Results NSCs highly expressed nestin. Compared with the control group, the level of MCP-1 mRNA significantly increased in the spinal cord injury group. The NSCs which were injected into the spinal cord migrated into the center of the injured site where F4/80 was highly expressed. Macrophages significantly increased the number of migrating NSCs in vitro and the secretion of MCP-1. Conclusion Macrophages induce NSC migrating into the spinal cord injury site possibly through promoting the secretion of MCP-1. PMID:27609570

  13. Soa genotype selectively affects mouse gustatory neural responses to sucrose octaacetate

    PubMed Central

    INOUE, MASASHI; LI, XIA; McCAUGHEY, STUART A.; BEAUCHAMP, GARY K.; BACHMANOV, ALEXANDER A.

    2013-01-01

    In mice, behavioral acceptance of the bitter compound sucrose octaacetate (SOA) depends on allelic variation of a single gene, Soa. The SW.B6-Soab congenic mouse strain has the genetic background of an “SOA taster” SWR/J strain and an Soa-containing donor chromosome fragment from an “SOA nontaster” C57BL/6J strain. Using microsatellite markers polymorphic between the two parental strains, we determined that the donor fragment spans 5–10 cM of distal chromosome 6. The SWR/J mice avoided SOA in two-bottle tests with water and had strong responses to SOA in two gustatory nerves, the chorda tympani (CT) and glossopharyngeal (GL). In contrast, the SW.B6-Soab mice were indifferent to SOA in two-bottle tests and had very weak responses to SOA in both of these nerves. The SWR/J and SW.B6-Soab mice did not differ in responses of either nerve to sucrose, NaCl, HCl, or the bitter-tasting stimuli quinine, denatonium, strychnine, 6-n-propylthiouracil, phenylthiocarbamide, and MgSO4. Thus the effect of the Soa genotype on SOA avoidance is mediated by peripheral taste responsiveness to SOA, involving taste receptor cells innervated by both the CT and GL nerves. PMID:11328963

  14. Neuroprotective effect of the endogenous neural peptide apelin in cultured mouse cortical neurons

    SciTech Connect

    Zeng, Xiang Jun; Yu, Shan Ping; Zhang, Like; Wei, Ling

    2010-07-01

    The adipocytokine apelin and its G protein-coupled APJ receptor were initially isolated from a bovine stomach and have been detected in the brain and cardiovascular system. Recent studies suggest that apelin can protect cardiomyocytes from ischemic injury. Here, we investigated the effect of apelin on apoptosis in mouse primary cultures of cortical neurons. Exposure of the cortical cultures to a serum-free medium for 24 h induced nuclear fragmentation and apoptotic death; apelin-13 (1.0-5.0 nM) markedly prevented the neuronal apoptosis. Apelin neuroprotective effects were mediated by multiple mechanisms. Apelin-13 reduced serum deprivation (SD)-induced ROS generation, mitochondria depolarization, cytochrome c release and activation of caspase-3. Apelin-13 prevented SD-induced changes in phosphorylation status of Akt and ERK1/2. In addition, apelin-13 attenuated NMDA-induced intracellular Ca{sup 2+} accumulation. These results indicate that apelin is an endogenous neuroprotective adipocytokine that may block apoptosis and excitotoxic death via cellular and molecular mechanisms. It is suggested that apelins may be further explored as a potential neuroprotective reagent for ischemia-induced brain damage.

  15. RNA sequencing from neural ensembles activated during fear conditioning in the mouse temporal association cortex.

    PubMed

    Cho, Jin-Hyung; Huang, Ben S; Gray, Jesse M

    2016-01-01

    The stable formation of remote fear memories is thought to require neuronal gene induction in cortical ensembles that are activated during learning. However, the set of genes expressed specifically in these activated ensembles is not known; knowledge of such transcriptional profiles may offer insights into the molecular program underlying stable memory formation. Here we use RNA-Seq to identify genes whose expression is enriched in activated cortical ensembles labeled during associative fear learning. We first establish that mouse temporal association cortex (TeA) is required for remote recall of auditory fear memories. We then perform RNA-Seq in TeA neurons that are labeled by the activity reporter Arc-dVenus during learning. We identify 944 genes with enriched expression in Arc-dVenus+ neurons. These genes include markers of L2/3, L5b, and L6 excitatory neurons but not glial or inhibitory markers, confirming Arc-dVenus to be an excitatory neuron-specific but non-layer-specific activity reporter. Cross comparisons to other transcriptional profiles show that 125 of the enriched genes are also activity-regulated in vitro or induced by visual stimulus in the visual cortex, suggesting that they may be induced generally in the cortex in an experience-dependent fashion. Prominent among the enriched genes are those encoding potassium channels that down-regulate neuronal activity, suggesting the possibility that part of the molecular program induced by fear conditioning may initiate homeostatic plasticity. PMID:27557751

  16. RNA sequencing from neural ensembles activated during fear conditioning in the mouse temporal association cortex

    PubMed Central

    Cho, Jin-Hyung; Huang, Ben S.; Gray, Jesse M.

    2016-01-01

    The stable formation of remote fear memories is thought to require neuronal gene induction in cortical ensembles that are activated during learning. However, the set of genes expressed specifically in these activated ensembles is not known; knowledge of such transcriptional profiles may offer insights into the molecular program underlying stable memory formation. Here we use RNA-Seq to identify genes whose expression is enriched in activated cortical ensembles labeled during associative fear learning. We first establish that mouse temporal association cortex (TeA) is required for remote recall of auditory fear memories. We then perform RNA-Seq in TeA neurons that are labeled by the activity reporter Arc-dVenus during learning. We identify 944 genes with enriched expression in Arc-dVenus+ neurons. These genes include markers of L2/3, L5b, and L6 excitatory neurons but not glial or inhibitory markers, confirming Arc-dVenus to be an excitatory neuron-specific but non-layer-specific activity reporter. Cross comparisons to other transcriptional profiles show that 125 of the enriched genes are also activity-regulated in vitro or induced by visual stimulus in the visual cortex, suggesting that they may be induced generally in the cortex in an experience-dependent fashion. Prominent among the enriched genes are those encoding potassium channels that down-regulate neuronal activity, suggesting the possibility that part of the molecular program induced by fear conditioning may initiate homeostatic plasticity. PMID:27557751

  17. Amyloid-β precursor protein induces glial differentiation of neural progenitor cells by activation of the IL-6/gp130 signaling pathway.

    PubMed

    Kwak, Young-Don; Dantuma, Elise; Merchant, Stephanie; Bushnev, Sergey; Sugaya, Kiminobu

    2010-11-01

    Although amyloid precursor protein (APP) due to the cytotoxicity of Aβ peptides, has been intensively studied, the physiological role of APP still remains wrapped up in veil. In this article, we propose that α-cleaved ectodomain of APP (sAPPα) stimulates the IL-6/gp130 signaling pathway for induction of gliogenesis within neural progenitor cells (NPCs). In our previous study, a high dose of APP differentiated NPCs into glial fibrillary acidic protein (GFAP) positive cells. In order to elucidate the mechanism of APP-induced glial differentiation, we examined the effects of sAPPα on the IL-6/gp130 signaling pathway. Application of sAPPα promoted mRNA expression of gp130, ciliary neurotrophic factor (CNTF), and Janus kinase 1 (JAK1). sAPPα stimulated the glial differentiation by upregulating the expression and phosphorylation of gp130. While mRNA expression of STAT3 was unchanged, phosphorylation of STAT3-Tyr705 gradually increased. Application of small interference RNA (siRNA) for STAT3 suppressed GFAP expression even in the presence of APP. Treatment with siRNA or inhibitor, AG490, of JAK1 efficiently suppressed STAT3 phosphorylation and GFAP expression. Upregulation of CNTF was observed in either short- or long-term treatment with sAPPα. RNA's interference of CNTF dose-dependently inhibited GFAP expression upregulated by treatment with sAPPα. This study suggests that the IL-6/gp130 signaling pathway is involved in sAPPα-induced glial differentiation of NPCs. Although further investigation is needed, this study may provide insight into the mechanism of glial differentiation of NPCs under pathological conditions in Alzheimer's disease or Down syndrome. PMID:20309664

  18. OTX2 exhibits cell-context-dependent effects on cellular and molecular properties of human embryonic neural precursors and medulloblastoma cells.

    PubMed

    Kaur, Ravinder; Aiken, Christopher; Morrison, Ludivine Coudière; Rao, Radhika; Del Bigio, Marc R; Rampalli, Shravanti; Werbowetski-Ogilvie, Tamra

    2015-10-01

    Medulloblastoma (MB) is the most common malignant primary pediatric brain tumor and is currently divided into four subtypes based on different genomic alterations, gene expression profiles and response to treatment: WNT, Sonic Hedgehog (SHH), Group 3 and Group 4. This extensive heterogeneity has made it difficult to assess the functional relevance of genes to malignant progression. For example, expression of the transcription factor Orthodenticle homeobox2 (OTX2) is frequently dysregulated in multiple MB variants; however, its role may be subtype specific. We recently demonstrated that neural precursors derived from transformed human embryonic stem cells (trans-hENs), but not their normal counterparts (hENs), resemble Groups 3 and 4 MB in vitro and in vivo. Here, we tested the utility of this model system as a means of dissecting the role of OTX2 in MB using gain- and loss-of-function studies in hENs and trans-hENs, respectively. Parallel experiments with MB cells revealed that OTX2 exerts inhibitory effects on hEN and SHH MB cells by regulating growth, self-renewal and migration in vitro and tumor growth in vivo. This was accompanied by decreased expression of pluripotent genes, such as SOX2, and was supported by overexpression of SOX2 in OTX2+ SHH MB and hENs that resulted in significant rescue of self-renewal and cell migration. By contrast, OTX2 is oncogenic and promotes self-renewal of trans-hENs and Groups 3 and 4 MB independent of pluripotent gene expression. Our results demonstrate a novel role for OTX2 in self-renewal and migration of hENs and MB cells and reveal a cell-context-dependent link between OTX2 and pluripotent genes. Our study underscores the value of human embryonic stem cell derivatives as alternatives to cell lines and heterogeneous patient samples for investigating the contribution of key developmental regulators to MB progression. PMID:26398939

  19. An In Vivo Characterization of Trophic Factor Production Following Neural Precursor Cell or Bone Marrow Stromal Cell Transplantation for Spinal Cord Injury

    PubMed Central

    Hawryluk, Gregory W.J.; Mothe, Andrea; Wang, Jian; Wang, Shelly; Tator, Charles

    2012-01-01

    Cellular transplantation strategies for repairing the injured spinal cord have shown consistent benefit in preclinical models, and human clinical trials have begun. Interactions between transplanted cells and host tissue remain poorly understood. Trophic factor secretion is postulated a primary or supplementary mechanism of action for many transplanted cells, however, there is little direct evidence to support trophin production by transplanted cells in situ. In the present study, trophic factor expression was characterized in uninjured, injured-untreated, injured-treated with transplanted cells, and corresponding control tissue from the adult rat spinal cord. Candidate trophic factors were identified in a literature search, and primers were designed for these genes. We examined in vivo trophin expression in 3 paradigms involving transplantation of either brain or spinal cord-derived neural precursor cells (NPCs) or bone marrow stromal cells (BMSCs). Injury without further treatment led to a significant elevation of nerve growth factor (NGF), leukemia inhibitory factor (LIF), insulin-like growth factor-1 (IGF-1), and transforming growth factor-β1 (TGF-β1), and lower expression of vascular endothelial growth factor isoform A (VEGF-A) and platelet-derived growth factor-A (PDGF-A). Transplantation of NPCs led to modest changes in trophin expression, and the co-administration of intrathecal trophins resulted in significant elevation of the neurotrophins, glial-derived neurotrophic factor (GDNF), LIF, and basic fibroblast growth factor (bFGF). BMSCs transplantation upregulated NGF, LIF, and IGF-1. NPCs isolated after transplantation into the injured spinal cord expressed the neurotrophins, ciliary neurotrophic factor (CNTF), epidermal growth factor (EGF), and bFGF at higher levels than host cord. These data show that trophin expression in the spinal cord is influenced by injury and cell transplantation, particularly when combined with intrathecal trophin infusion

  20. Insulin-Like Growth Factor Receptor Signaling is Necessary for Epidermal Growth Factor Mediated Proliferation of SVZ Neural Precursors in vitro Following Neonatal Hypoxia–Ischemia

    PubMed Central

    Alagappan, Dhivyaa; Ziegler, Amber N.; Chidambaram, Shravanthi; Min, Jungsoo; Wood, Teresa L.; Levison, Steven W.

    2014-01-01

    In this study, we assessed the importance of insulin-like growth factor (IGF) and epidermal growth factor (EGF) receptor co-signaling for rat neural precursor (NP) cell proliferation and self-renewal in the context of a developmental brain injury that is associated with cerebral palsy. Consistent with previous studies, we found that there is an increase in the in vitro growth of subventricular zone NPs isolated acutely after cerebral hypoxia–ischemia; however, when cultured in medium that is insufficient to stimulate the IGF type 1 receptor, neurosphere formation and the proliferative capacity of those NPs was severely curtailed. This reduced growth capacity could not be attributed simply to failure to survive. The growth and self-renewal of the NPs could be restored by addition of both IGF-I and IGF-II. Since the size of the neurosphere is predominantly due to cell proliferation we hypothesized that the IGFs were regulating progression through the cell cycle. Analyses of cell cycle progression revealed that IGF-1R activation together with EGFR co-signaling decreased the percentage of cells in G1 and enhanced cell progression into S and G2. This was accompanied by increases in expression of cyclin D1, phosphorylated histone 3, and phosphorylated Rb. Based on these data, we conclude that coordinate signaling between the EGF receptor and the IGF type 1 receptor is necessary for the normal proliferation of NPs as well as for their reactive expansion after injury. These data indicate that manipulations that maintain or amplify IGF signaling in the brain during recovery from developmental brain injuries will enhance the production of new brain cells to improve neurological function in children who are at risk for developing cerebral palsy. PMID:24904523

  1. Critical role of astrocytic interleukin-17 A in post-stroke survival and neuronal differentiation of neural precursor cells in adult mice.

    PubMed

    Lin, Y; Zhang, J-C; Yao, C-Y; Wu, Y; Abdelgawad, A F; Yao, S-L; Yuan, S-Y

    2016-01-01

    The brain and the immune system interact in complex ways after ischemic stroke, and the long-term effects of immune response associated with stroke remain controversial. As a linkage between innate and adaptive immunity, interleukin-17 A (IL-17 A) secreted from gamma delta (γδ) T cells has detrimental roles in the pathogenesis of acute ischemic stroke. However, to date, the long-term actions of IL-17 A after stroke have not been investigated. Here, we found that IL-17 A showed two distinct peaks of expression in the ischemic hemisphere: the first occurring within 3 days and the second on day 28 after stroke. Our data also showed that astrocyte was the major cellular source of IL-17 A that maintained and augmented subventricular zone (SVZ) neural precursor cells (NPCs) survival, neuronal differentiation, and subsequent synaptogenesis and functional recovery after stroke. IL-17 A also promoted neuronal differentiation in cultured NPCs from the ischemic SVZ. Furthermore, our in vitro data revealed that in primary astrocyte cultures activated astrocytes released IL-17 A via p38 mitogen-activated protein kinase (MAPK). Culture media from reactive astrocytes increased neuronal differentiation of NSCs in vitro. Blockade of IL-17 A with neutralizing antibody prevented this effect. In addition, after screening for multiple signaling pathways, we revealed that the p38 MAPK/calpain 1 signaling pathway was involved in IL-17 A-mediated neurogenesis in vivo and in vitro. Thus, our results reveal a previously uncharacterized property of astrocytic IL-17 A in the maintenance and augment of survival and neuronal differentiation of NPCs, and subsequent synaptogenesis and spontaneous recovery after ischemic stroke. PMID:27336717

  2. A Cre-lox approach for transient transgene expression in neural precursor cells and long-term tracking of their progeny in vitro and in vivo

    PubMed Central

    Geoffroy, Cédric G; Raineteau, Olivier

    2007-01-01

    Background Neural precursor cells (NPCs) can be isolated from various regions of the postnatal central nervous system (CNS). Manipulation of gene expression in these cells offers a promising strategy to manipulate their fate both in vitro and in vivo. In this study, we developed a technique that allows the transient manipulation of single/multiple gene expression in NPCs in vitro, and the long-term tracking of their progeny both in vitro and in vivo. Results In order to combine the advantages of transient transfection with the long-term tracking of the transfected cells progeny, we developed a new approach based on the cre-lox technology. We first established a fast and reliable protocol to isolate and culture NPCs as monolayer, from the spinal cord of neonatal transgenic Rosa26-YFP cre-reporter mice. These cells could be reliably transfected with single/multiple plasmids by nucleofection. Nucleofection with mono- or bicistronic plasmids containing the Cre recombinase gene resulted in efficient recombination and the long-term expression of the YFP-reporter gene. The transient cre-expression was non-toxic for the transfected cells and did not alter their intrinsic properties. Finally, we demonstrated that cre-transfected cells could be transplanted into the adult brain, where they maintained YFP expression permitting long-term tracking of their migration and differentiation. Conclusion This approach allows single/multiple genes to be manipulated in NPCs, while at the same time allowing long-term tracking of the transfected cells progeny to be analyzed both in vitro and in vivo. PMID:17504531

  3. Arsenate-induced maternal glucose intolerance and neural tube defects in a mouse model

    SciTech Connect

    Hill, Denise S.; Wlodarczyk, Bogdan J.; Mitchell, Laura E.; Finnell, Richard H.

    2009-08-15

    Background: Epidemiological studies have linked environmental arsenic (As) exposure to increased type 2 diabetes risk. Periconceptional hyperglycemia is a significant risk factor for neural tube defects (NTDs), the second most common structural birth defect. A suspected teratogen, arsenic (As) induces NTDs in laboratory animals. Objectives: We investigated whether maternal glucose homeostasis disruption was responsible for arsenate-induced NTDs in a well-established dosing regimen used in studies of arsenic's teratogenicity in early neurodevelopment. Methods: We evaluated maternal intraperitoneal (IP) exposure to As 9.6 mg/kg (as sodium arsenate) in LM/Bc/Fnn mice for teratogenicity and disruption of maternal plasma glucose and insulin levels. Selected compounds (insulin pellet, sodium selenate (SS), N-acetyl cysteine (NAC), L-methionine (L-Met), N-tert-Butyl-{alpha}-phenylnitrone (PBN)) were investigated for their potential to mitigate arsenate's effects. Results: Arsenate caused significant glucose elevation during an IP glucose tolerance test (IPGTT). Insulin levels were not different between arsenate and control dams before (arsenate, 0.55 ng/dl; control, 0.48 ng/dl) or after glucose challenge (arsenate, 1.09 ng/dl; control, 0.81 ng/dl). HOMA-IR index was higher for arsenate (3.9) vs control (2.5) dams (p = 0.0260). Arsenate caused NTDs (100%, p < 0.0001). Insulin pellet and NAC were the most successful rescue agents, reducing NTD rates to 45% and 35%. Conclusions: IPGTT, insulin assay, and HOMA-IR results suggest a modest failure of glucose stimulated insulin secretion and insulin resistance characteristic of glucose intolerance. Insulin's success in preventing arsenate-induced NTDs provides evidence that these arsenate-induced NTDs are secondary to elevated maternal glucose. The NAC rescue, which did not restore maternal glucose or insulin levels, suggests oxidative disruption plays a role.

  4. Effect of trichostatin A on gelsolin levels, proteolysis of amyloid precursor protein, and amyloid beta-protein load in the brain of transgenic mouse model of Alzheimer's disease.

    PubMed

    Yang, Wenzhong; Chauhan, Abha; Wegiel, Jerzy; Kuchna, Izabela; Gu, Feng; Chauhan, Ved

    2014-01-01

    In vivo and in vitro studies have shown that gelsolin is an anti-amyloidogenic protein. Trichostatin A (TSA), a histone deacetylase (HDAC) inhibitor, promotes the expression of gelsolin. Fibrillized amyoid beta-protein (Aβ) is a key constituent of amyloid plaques in the brains of patients with Alzheimer's disease (AD). We studied the effects of TSA on the levels of gelsolin; amyloid precursor protein (APP); proteolytic enzymes (γ-secretase and β-secretase) responsible for the production of Aβ; Aβ-cleaving enzymes, i.e., neprilysin (NEP) and insulin-degrading enzyme (IDE); and amyloid load in the double transgenic (Tg) APPswe/PS1(δE9) mouse model of AD. Intraperitoneal injection of TSA for two months (9-11 months of age) resulted in decreased activity of HDAC, and increased levels of gelsolin in the hippocampus and cortex of the brain in AD Tg mice as compared to vehicle-treated mice. TSA also increased the levels of γ-secretase and β-secretase activity in the brain. However, TSA did not show any effect on the activities or the expression levels of NEP and IDE in the brain. Furthermore, TSA treatment of AD Tg mice showed no change in the amyloid load (percent of examined area occupied by amyloid plaques) in the hippocampus and cortex, suggesting that TSA treatment did not result in the reduction of amyloid load. Interestingly, TSA prevented the formation of new amyloid deposits but increased the size of existing plaques. TSA treatment did not cause any apoptosis in the brain. These results suggest that TSA increases gelsolin expression in the brain, but the pleiotropic effects of TSA negate the anti-amyloidogenic effect of gelsolin in AD Tg mice. PMID:25387339

  5. E mu/S mu transposition into Myc is sometimes a precursor for T(12;15) translocation in mouse B cells.

    PubMed

    Kovalchuk, Alexander L; Kim, Joong Su; Janz, Siegfried

    2003-05-01

    Misguided immunoglobulin (Ig) class switch recombination (CSR) has been implicated in the origin of Myc-activating chromosomal translocations, T(12;15), in BALB/c mouse plasmacytomas (PCTs). CSR has also been involved in the progression of T(12;15); for example, the approximation of Myc to the 3'-C alpha enhancer. This study provides evidence for an additional mechanism by which aberrant CSR may facilitate T(12;15): transposition of Ig heavy-chain (IgH) sequences to Myc. Five IgH transposons containing the intronic heavy-chain enhancer, E mu, and a truncated switch mu region, S mu, were found in the first intron of Myc in lymph node cells of IL-6 transgenic BALB/c mice. In two cases E mu/S mu transposition primed Myc to get involved in apparent trans-chromosomal CSR to C gamma 1, presumably leading to T(12;15). Translocations preceded by E mu/S mu transposition can sometimes be distinguished from de novo translocations by molecular fingerprints in translocation breakpoint regions (Ig switch region [S] inversions and unusual gene orders in composite S regions). The presence of such fingerprints in some PCTs suggests that the tumors sometimes evolve from transposition-bearing precursors. We propose that E mu/S mu transposition to Myc may facilitate plasmacytomagenesis by sensitizing Myc to undergo T(12;15) translocation. T(12;15), in turn, juxtaposes Myc to the 3'-C alpha enhancer, which appears to be required for deregulating Myc in a manner that is conducive to PCT development. PMID:12743607

  6. Effects of epigallocatechin-3-gallate on proliferation and differentiation of mouse cochlear neural stem cells: Involvement of PI3K/Akt signaling pathway.

    PubMed

    Zhang, Yubo; He, Qiang; Dong, Jinhui; Jia, Zhanwei; Hao, Fang; Shan, Chunguang

    2016-06-10

    Since the majority of hearing impaired patients suffer from the significant loss of sensory hair cells and associated neurons, stem cell-based approaches hold great promise by replacing the damaged tissues in the ears. For instance, stem cells from the spiral ganglion could be isolated and expanded to regenerate neural structures of the inner ear. It is thus necessary to explore the potential procedures that may promote the proliferation and differentiation of such cochlear neural stem cells. In the present study, we study the effects of epigallocatechin-3-gallate (EGCG), a known antioxidant, for potential therapeutic use in NSC regeneration. At a non-toxic concentration, EGCG stimulated both proliferation and neurosphere formation in isolated mouse cochlear neural stem cell (NSC) in vitro. Specifically, the neural differentiation of NSC was promoted by EGCG treatment. The up-regulated neural function by EGCG was also supported by the increased calcium spike frequencies and enhanced neurite complexity in NSC-differentiated neurons. Finally, the induced neuron differentiation and Akt activation of cochlear NSC by EGCG were blocked by PI3 kinase inhibition. These data suggested that EGCG acts through phosphoinositide 3-kinase (PI3K)/Akt signaling in cochlea NSC to promote cell growth and neuron differentiation, which may be exploited for the treatment of hearing loss. PMID:27012759

  7. Mutation of Celsr1 disrupts planar polarity of inner ear hair cells and causes severe neural tube defects in the mouse.

    PubMed

    Curtin, John A; Quint, Elizabeth; Tsipouri, Vicky; Arkell, Ruth M; Cattanach, Bruce; Copp, Andrew J; Henderson, Deborah J; Spurr, Nigel; Stanier, Philip; Fisher, Elizabeth M; Nolan, Patrick M; Steel, Karen P; Brown, Steve D M; Gray, Ian C; Murdoch, Jennifer N

    2003-07-01

    We identified two novel mouse mutants with abnormal head-shaking behavior and neural tube defects during the course of independent ENU mutagenesis experiments. The heterozygous and homozygous mutants exhibit defects in the orientation of sensory hair cells in the organ of Corti, indicating a defect in planar cell polarity. The homozygous mutants exhibit severe neural tube defects as a result of failure to initiate neural tube closure. We show that these mutants, spin cycle and crash, carry independent missense mutations within the coding region of Celsr1, encoding a large protocadherin molecule [1]. Celsr1 is one of three mammalian homologs of Drosophila flamingo/starry night, which is essential for the planar cell polarity pathway in Drosophila together with frizzled, dishevelled, prickle, strabismus/van gogh, and rhoA. The identification of mouse mutants of Celsr1 provides the first evidence for the function of the Celsr family in planar cell polarity in mammals and further supports the involvement of a planar cell polarity pathway in vertebrate neurulation. PMID:12842012

  8. Epidermal Neural Crest Stem Cell (EPI-NCSC)—Mediated Recovery of Sensory Function in a Mouse Model of Spinal Cord Injury

    PubMed Central

    Hu, Yao Fei; Gourab, Krishnaj; Wells, Clive; Clewes, Oliver; Schmit, Brian D.

    2010-01-01

    Here we show that epidermal neural crest stem cell (EPI-NCSC) transplants in the contused spinal cord caused a 24% improvement in sensory connectivity and a substantial recovery of touch perception. Furthermore we present a novel method for the ex vivo expansion of EPI-NCSC into millions of stem cells that takes advantage of the migratory ability of neural crest stem cells and is based on a new culture medium and the use of microcarriers. Functional improvement was shown by two independent methods, spinal somatosensory evoked potentials (SpSEP) and the Semmes-Weinstein touch test. Subsets of transplanted cells differentiated into myelinating oligodendrocytes. Unilateral injections of EPI-NCSC into the lesion of midline contused mouse spinal cords elicited bilateral improvements. Intraspinal EPI-NCSC did not migrate laterally in the spinal cord or invade the spinal roots and dorsal root ganglia, thus implicating diffusible factors. EPI-NCSC expressed neurotrophic factors, angiogenic factors, and metalloproteases. The strength of EPI-NCSC thus is that they can exert a combination of pertinent functions in the contused spinal cord, including cell replacement, neuroprotection, angiogenesis and modulation of scar formation. EPI-NCSC are uniquely qualified for cell-based therapy in spinal cord injury, as neural crest cells and neural tube stem cells share a higher order stem cell and are thus ontologically closely related. PMID:20414748

  9. Brca1 is required for embryonic development of the mouse cerebral cortex to normal size by preventing apoptosis of early neural progenitors.

    PubMed

    Pulvers, Jeremy N; Huttner, Wieland B

    2009-06-01

    The extent of apoptosis of neural progenitors is known to influence the size of the cerebral cortex. Mouse embryos lacking Brca1, the ortholog of the human breast cancer susceptibility gene BRCA1, show apoptosis in the neural tube, but the consequences of this for brain development have not been studied. Here we investigated the role of Brca1 during mouse embryonic cortical development by deleting floxed Brca1 using Emx1-Cre, which leads to conditional gene ablation specifically in the dorsal telencephalon after embryonic day (E) 9.5. The postnatal Brca1-ablated cerebral cortex was substantially reduced in size with regard to both cortical thickness and surface area. Remarkably, although the thickness of the cortical layers (except for the upper-most layer) was decreased, cortical layering as such was essentially unperturbed. High levels of apoptosis were found at E11.5 and E13.5, but dropped to near-control levels by E16.5. The apoptosis at the early stage of neurogenesis occurred in both BrdU pulse-labeled neural progenitors and the neurons derived therefrom. No changes were observed in the mitotic index of apical (neuroepithelial, radial glial) progenitors and basal (intermediate) progenitors, indicating that Brca1 ablation did not affect cell cycle progression. Brca1 ablation did, however, result in the nuclear translocation of p53 in neural progenitors, suggesting that their apoptosis involved activation of the p53 pathway. Our results show that Brca1 is required for the cerebral cortex to develop to normal size by preventing the apoptosis of early cortical progenitors and their immediate progeny. PMID:19403657

  10. Morphological comparison of the craniofacial phenotypes of mouse models expressing the Apert FGFR2 S252W mutation in neural crest- or mesoderm-derived tissues

    PubMed Central

    Heuzé, Yann; Singh, Nandini; Basilico, Claudio; Jabs, Ethylin Wang; Holmes, Greg; Richtsmeier, Joan T

    2014-01-01

    Bones of the craniofacial skeleton are derived from two distinct cell lineages, cranial neural crest and mesoderm, and articulate at sutures and synchondroses which represent major bone growth sites. Premature fusion of cranial suture(s) is associated with craniofacial dysmorphogenesis caused in part by alteration in the growth potential at sutures and can occur as an isolated birth defect or as part of a syndrome, such as Apert syndrome. Conditional expression of the Apert FGFR2 S252W mutation in mesoderm was previously shown to be necessary and sufficient to cause coronal craniosynostosis. Here we used micro computed tomography images of mice expressing the Apert mutation constitutively in either mesoderm or neural crest to quantify craniofacial shape variation and suture fusion patterns, and to identify shape changes in craniofacial bones derived from the lineage not expressing the mutation, referred to here as secondary shape changes. Our results show that at postnatal day 0: (i) conditional expression of the FGFR2 S252W mutation in neural crest-derived tissues causes a more severe craniofacial phenotype than when expressed in mesoderm-derived tissues; and (ii) both mesoderm- and neural crest-specific mouse models display secondary shape changes. We also show that premature suture fusion is not necessarily dependent on the expression of the FGFR2 S252W mutation in the sutural mesenchyme. More specifically, it appears that suture fusion patterns in both mouse models are suture-specific resulting from a complex combination of the influence of primary abnormalities of biogenesis or signaling within the sutures, and timing. PMID:24632501

  11. Analysis of the mouse mutant Cloth-ears shows a role for the voltage-gated sodium channel Scn8a in peripheral neural hearing loss.

    PubMed

    Mackenzie, F E; Parker, A; Parkinson, N J; Oliver, P L; Brooker, D; Underhill, P; Lukashkina, V A; Lukashkin, A N; Holmes, C; Brown, S D M

    2009-10-01

    Deafness is the most common sensory disorder in humans and the aetiology of genetic deafness is complex. Mouse mutants have been crucial in identifying genes involved in hearing. However, many deafness genes remain unidentified. Using N-ethyl N-nitrosourea (ENU) mutagenesis to generate new mouse models of deafness, we identified a novel semi-dominant mouse mutant, Cloth-ears (Clth). Cloth-ears mice show reduced acoustic startle response and mild hearing loss from approximately 30 days old. Auditory-evoked brainstem response (ABR) and distortion product otoacoustic emission (DPOAE) analyses indicate that the peripheral neural auditory pathway is impaired in Cloth-ears mice, but that cochlear function is normal. In addition, both Clth/Clth and Clth/+ mice display paroxysmal tremor episodes with behavioural arrest. Clth/Clth mice also show a milder continuous tremor during movement and rest. Longitudinal phenotypic analysis showed that Clth/+ and Clth/Clth mice also have complex defects in behaviour, growth, neurological and motor function. Positional cloning of Cloth-ears identified a point mutation in the neuronal voltage-gated sodium channel alpha-subunit gene, Scn8a, causing an aspartic acid to valine (D981V) change six amino acids downstream of the sixth transmembrane segment of the second domain (D2S6). Complementation testing with a known Scn8a mouse mutant confirmed that this mutation is responsible for the Cloth-ears phenotype. Our findings suggest a novel role for Scn8a in peripheral neural hearing loss and paroxysmal motor dysfunction. PMID:19737145

  12. Neural transcription factors bias cleavage stage blastomeres to give rise to neural ectoderm.

    PubMed

    Gaur, Shailly; Mandelbaum, Max; Herold, Mona; Majumdar, Himani Datta; Neilson, Karen M; Maynard, Thomas M; Mood, Kathy; Daar, Ira O; Moody, Sally A

    2016-06-01

    The decision by embryonic ectoderm to give rise to epidermal versus neural derivatives is the result of signaling events during blastula and gastrula stages. However, there also is evidence in Xenopus that cleavage stage blastomeres contain maternally derived molecules that bias them toward a neural fate. We used a blastomere explant culture assay to test whether maternally deposited transcription factors bias 16-cell blastomere precursors of epidermal or neural ectoderm to express early zygotic neural genes in the absence of gastrulation interactions or exogenously supplied signaling factors. We found that Foxd4l1, Zic2, Gmnn, and Sox11 each induced explants made from ventral, epidermis-producing blastomeres to express early neural genes, and that at least some of the Foxd4l1 and Zic2 activities are required at cleavage stages. Similarly, providing extra Foxd4l1 or Zic2 to explants made from dorsal, neural plate-producing blastomeres significantly increased the expression of early neural genes, whereas knocking down either significantly reduced them. These results show that maternally delivered transcription factors bias cleavage stage blastomeres to a neural fate. We demonstrate that mouse and human homologs of Foxd4l1 have similar functional domains compared to the frog protein, as well as conserved transcriptional activities when expressed in Xenopus embryos and blastomere explants. genesis 54:334-349, 2016. © 2016 Wiley Periodicals, Inc. PMID:27092474

  13. Cellular and molecular mechanisms of the restoration of human APP transgenic mouse cognitive dysfunction after transplant of human iPS cell-derived neural cells.

    PubMed

    Fujiwara, Naruyoshi; Shimizu, Jun; Takai, Kenji; Arimitsu, Nagisa; Ueda, Yuji; Wakisaka, Sueshige; Suzuki, Tomoko; Suzuki, Noboru

    2015-09-01

    Cholinergic neuronal loss is a common finding in patients with Alzheimer's disease (AD) and AD model mice. We previously transplanted neurons derived from human induced pluripotent stem (iPS) cells into the hippocampus of human amyloid precursor protein transgenic AD model mice. In the present study, we examined the cellular and molecular mechanisms involved in the alleviation of cognitive dysfunction in transplanted mice. After transplant, mice showed improvement in cognitive function, confirming our previous findings. Human choline acetyltransferase (ChAT)-positive cholinergic neurons were distributed throughout the cortex of the grafted mice. Human and mouse ChAT-positive neurons and alpha7 nicotinic acetylcholine receptor (α7nAChR)-positive neurons were significantly increased in the cortex and hippocampus of the grafted mice compared with the vehicle-injected mice. In addition, human and mouse vesicular GABA transporter (VGAT)-positive neurons were located mainly in the hippocampus and, though the number was small, human VGAT-positive neurons were observed in the cortex. In the grafted mouse cortex, the number of GABA receptor (GABAR)-positive neurons of both human origin and mouse origin were significantly increased compared with those in the vehicle-injected mouse cortex. The α7nAChR-positive and GABAR-positive neurons expressed phosphorylated Akt and c-fos in the cortex, suggesting that these receptor-expressing neurons were possibly activated by the neurotransmitters secreted from the grafted neurons. Collectively, the grafted and host neurons may form positive feedback loops via neurotransmitter secretion in both the cerebral cortex and hippocampus, leading to alleviation of cognitive dysfunction in dementia model mice. PMID:26196079

  14. Identification of Stage-Specific Gene Expression Signatures in Response to Retinoic Acid during the Neural Differentiation of Mouse Embryonic Stem Cells

    PubMed Central

    Akanuma, Hiromi; Qin, Xian-Yang; Nagano, Reiko; Win-Shwe, Tin-Tin; Imanishi, Satoshi; Zaha, Hiroko; Yoshinaga, Jun; Fukuda, Tomokazu; Ohsako, Seiichiroh; Sone, Hideko

    2012-01-01

    We have previously established a protocol for the neural differentiation of mouse embryonic stem cells (mESCs) as an efficient tool to evaluate the neurodevelopmental toxicity of environmental chemicals. Here, we described a multivariate bioinformatic approach to identify the stage-specific gene sets associated with neural differentiation of mESCs. We exposed mESCs (B6G-2 cells) to 10−8 or 10−7 M of retinoic acid (RA) for 4 days during embryoid body formation and then performed morphological analysis on day of differentiation (DoD) 8 and 36, or genomic microarray analysis on DoD 0, 2, 8, and 36. Three gene sets, namely a literature-based gene set (set 1), an analysis-based gene set (set 2) using self-organizing map and principal component analysis, and an enrichment gene set (set 3), were selected by the combined use of knowledge from literatures and gene information selected from the microarray data. A gene network analysis for each gene set was then performed using Bayesian statistics to identify stage-specific gene expression signatures in response to RA during mESC neural differentiation. Our results showed that RA significantly increased the size of neurosphere, neuronal cells, and glial cells on DoD 36. In addition, the gene network analysis showed that glial fibrillary acidic protein, a neural marker, remarkably up-regulates the other genes in gene set 1 and 3, and Gbx2, a neural development marker, significantly up-regulates the other genes in gene set 2 on DoD 36 in the presence of RA. These findings suggest that our protocol for identification of developmental stage-specific gene expression and interaction is a useful method for the screening of environmental chemical toxicity during neurodevelopmental periods. PMID:22891073

  15. Differential overexpression of three mdr gene family members in multidrug-resistant J774.2 mouse cells. Evidence that distinct P-glycoprotein precursors are encoded by unique mdr genes.

    PubMed

    Hsu, S I; Lothstein, L; Horwitz, S B

    1989-07-15

    A hallmark of the multidrug-resistant phenotype is the overproduction of a family of 130-180-kDa integral membrane phosphoglycoproteins collectively called P-glycoprotein. Gene-specific hybridization probes were derived from three classes of mouse P-glycoprotein cDNAs. These probes revealed the differential amplification and/or transcriptional activation of three distinct but closely related mdr genes (mdr1a, mdr1b, and mdr2) in independently selected multidrug-resistant J774.2 mouse cell lines. Overexpression of mdr1a and mdr1b was found to correlate, in general, with the differential overproduction of either a 120- or 125-kDa P-glycoprotein precursor, respectively. This same correlation was observed in a single cell line during the course of stepwise selection for resistance to vinblastine in which a switch in gene expression from mdr1b to mdr1a resulted in a switch from the 125- to 120-kDa P-glycoprotein precursor. These findings suggest that differential overexpression of distinct mdr genes which encode unique P-glycoprotein isoforms is a possible mechanism for generating diversity in the multidrug-resistant phenotype. PMID:2473069

  16. Effects of 12-O-tetradecanoylphorbol-13-acetate on the incorporation of labelled precursors into RNA, DNA and protein in epidermis, dermis and subcutis from precancerous mouse skin with reference to enhanced tumorigenesis

    SciTech Connect

    Bhisey, R.A.; Ramchandani, A.G.; Sirsat, S.M.

    1984-02-01

    The effects of a single application of 1.8 nmol 12-O-tetradecanoylphorbol-13-acetate (TPA) on precursor incorporation into RNA, DNA and protein in the epidermis, dermis and subcutis from 3-methylcholanthrene (MCA) injected precancerous mouse skin were studied at various time points between 3 and 96 h. In the precancerous tissues, the rates of incorporation of (/sup 3/H)uridine into RNA did not alter appreciably from those in the control tissues; while the rates of (/sup 3/H)methylthymidine incorporation into DNA were elevated with peaks appearing between 6 and 12 h, at 24 h and at 72 h in epidermis, dermis and subcutis. The rate of incorporation of (/sup 14/C)leucine into protein was markedly elevated in all the three tissues which showed 3-4 sharp peaks. The maximum stimulation ranged between 14 and 20 times that of the control. A single application of TPA to the precancerous mouse skin induced early stimulation of precursor incorporation into all the three macromolecules in epidermis, dermis and subcutis. The increased stimulation was maintained for 36-72 h. The patterns of incorporation of (/sup 3/H)methylthymidine into DNA gave rise to 2-3 peaks of elevated uptake in each tissue up to 36-48 h. A lowered rate of DNA synthesis between 48 and 60 h was followed by a peak at 72 h. In each group, epidermal mitotic activity correlated well with spurts of precursor incorporation into cellular DNA. The observations indicate that TPA recruits more cells into the DNA synthetic phase and accelerates selective growth of preneoplastic cells during tumor progression.

  17. CD9 of mouse brain is implicated in neurite outgrowth and cell migration in vitro and is associated with the alpha 6/beta 1 integrin and the neural adhesion molecule L1.

    PubMed

    Schmidt, C; Künemund, V; Wintergerst, E S; Schmitz, B; Schachner, M

    1996-01-01

    We describe here a novel monoclonal antibody (mab H6) which recognizes CD9, an integral cell surface constituent previously described in cells of the hematopoietic lineage and involved in the aggregation of platelets. Mab H6 was raised against membranes of immature mouse astrocytes and reacted with a protein of 25-27 kD in detergent extracts of adult mouse brain membranes. Sequence analysis of the N-terminal amino acids revealed an identity of 96% with CD9 from mouse kidney. CD9 was localized in the central and peripheral mouse nervous systems: in the spinal cord of 11-day-old mouse embryos, CD9 was strongly expressed in the floor and roof plates. In the adult mouse sciatic nerve, myelin sheaths were highly CD9-immunoreactive. Mab H6 reacted with the cell surfaces of both glial cells and neurons in culture and inhibited migration of neuronal cell bodies, neurite fasciculation and outgrowth of astrocytic processes from cerebellar microexplants. Neurite outgrowth from isolated small cerebellar neurons was increased in the presence of mab H6 on substrate-coated laminin, but not on substrate-coated poly-L-lysine. Addition of mab H6 elicited an increase in intracellular Ca2+ concentration in these cells on substrate-coated laminin. Immunoprecipitates of CD9 from cultured mouse neuroblastoma N2A cells contained the alpha 6/beta 1 integrin. Moreover, preparations of CD9 immunoaffinity-purified from adult mouse brain using a mab H6 column contained the neural adhesion molecule L1, but not other neural adhesion molecules. CD9 bound to L1, but not to NCAM or MAG. Both the alpha 6/beta 1 integrin and L1 could be induced to coredistribute with CD9 on the surface of cultured neuroblastoma N2A cells. The combined observations suggest that CD9 can associate with L1 and alpha 6/beta 1 integrin to influence neural cell interactions in vitro. PMID:8838570

  18. Arylsulfatase A Overexpressing Human iPSC-derived Neural Cells Reduce CNS Sulfatide Storage in a Mouse Model of Metachromatic Leukodystrophy.

    PubMed

    Doerr, Jonas; Böckenhoff, Annika; Ewald, Benjamin; Ladewig, Julia; Eckhardt, Matthias; Gieselmann, Volkmar; Matzner, Ulrich; Brüstle, Oliver; Koch, Philipp

    2015-09-01

    Metachromatic leukodystrophy (MLD) is an inherited lysosomal storage disorder resulting from a functional deficiency of arylsulfatase A (ARSA), an enzyme that catalyzes desulfation of 3-O-sulfogalactosylceramide (sulfatide). Lack of active ARSA leads to the accumulation of sulfatide in oligodendrocytes, Schwann cells and some neurons and triggers progressive demyelination, the neuropathological hallmark of MLD. Several therapeutic approaches have been explored, including enzyme replacement, autologous hematopoietic stem cell-based gene therapy, intracerebral gene therapy or cell-based gene delivery into the central nervous system (CNS). However, long-term treatment of the blood-brain-barrier protected CNS remains challenging. Here we used MLD patient-derived induced pluripotent stem cells (iPSCs) to generate long-term self-renewing neuroepithelial stem cells and astroglial progenitors for cell-based ARSA replacement. Following transplantation of ARSA-overexpressing precursors into ARSA-deficient mice we observed a significant reduction of sulfatide storage up to a distance of 300 µm from grafted cells. Our data indicate that neural precursors generated via reprogramming from MLD patients can be engineered to ameliorate sulfatide accumulation and may thus serve as autologous cell-based vehicle for continuous ARSA supply in MLD-affected brain tissue. PMID:26061647

  19. The role of the mesenchyme in mouse neural fold elevation. II. Patterns of hyaluronate synthesis and distribution in embryos developing in vitro

    SciTech Connect

    Morris-Wiman, J.; Brinkley, L.L. )

    1990-06-01

    Hyaluronate (HA) distribution patterns were examined in the cranial mesenchyme underlying the mesencephalic neural folds of mouse embryos maintained in roller tube culture. Using standard image-processing techniques, the digitized images of Alcian blue-stained or 3H-glucosamine-labeled sections digested with an enzyme specific for HA, were subtracted from adjacent, undigested sections. The resultant difference picture images (DPI) accurately depicted the distribution of stained or labeled HA within the cranial mesenchyme. 3H-glucosamine-labeled HA was distributed uniformly throughout the cranial mesenchyme as 12, 18, and 24 hr of culture. By contrast, the mesenchyme was uniformly stained with Alcian blue at 12 hr, but stain intensity decreased in the central regions of the mesenchyme at 18 and 24 hr. HA distribution patterns were also examined in the cranial mesenchyme of embryos cultured in the presence of diazo-oxo-norleucine (DON), a glutamine analogue that inhibits glycosaminoglycan and glycoprotein synthesis. In DON-treated mesenchyme, Alcian blue staining of HA was decreased from that in controls at 12, 18, and 24 hr. However, incorporation of 3H-glucosamine into HA was increased. The distribution of labeled HA within treated mesenchyme as 12, 18, and 24 hr resembled that in controls at 12 hr. These results indicate that the distribution of HA within the cranial mesenchyme of normal mouse embryos during neural fold elevation and convergence is not determined solely by regional differences in HA synthesis. We propose that HA distribution patterns result from the expansion of the HA-rich extracellular matrix of the central mesenchyme regions. This expansion may play a major role in fold elevation. These results also suggest that DON treatment reversibly inhibits HA synthesis.

  20. CRISPR/Cas9-induced disruption of gene expression in mouse embryonic brain and single neural stem cells in vivo.

    PubMed

    Kalebic, Nereo; Taverna, Elena; Tavano, Stefania; Wong, Fong Kuan; Suchold, Dana; Winkler, Sylke; Huttner, Wieland B; Sarov, Mihail

    2016-03-01

    We have applied the CRISPR/Cas9 system in vivo to disrupt gene expression in neural stem cells in the developing mammalian brain. Two days after in utero electroporation of a single plasmid encoding Cas9 and an appropriate guide RNA (gRNA) into the embryonic neocortex of Tis21::GFP knock-in mice, expression of GFP, which occurs specifically in neural stem cells committed to neurogenesis, was found to be nearly completely (≈90%) abolished in the progeny of the targeted cells. Importantly, upon in utero electroporation directly of recombinant Cas9/gRNA complex, near-maximal efficiency of disruption of GFP expression was achieved already after 24 h. Furthermore, by using microinjection of the Cas9 protein/gRNA complex into neural stem cells in organotypic slice culture, we obtained disruption of GFP expression within a single cell cycle. Finally, we used either Cas9 plasmid in utero electroporation or Cas9 protein complex microinjection to disrupt the expression of Eomes/Tbr2, a gene fundamental for neocortical neurogenesis. This resulted in a reduction in basal progenitors and an increase in neuronal differentiation. Thus, the present in vivo application of the CRISPR/Cas9 system in neural stem cells provides a rapid, efficient and enduring disruption of expression of specific genes to dissect their role in mammalian brain development. PMID:26758805

  1. Mouse IDGenes: a reference database for genetic interactions in the developing mouse brain

    PubMed Central

    Matthes, Michaela; Preusse, Martin; Zhang, Jingzhong; Schechter, Julia; Mayer, Daniela; Lentes, Bernd; Theis, Fabian; Prakash, Nilima; Wurst, Wolfgang; Trümbach, Dietrich

    2014-01-01

    The study of developmental processes in the mouse and other vertebrates includes the understanding of patterning along the anterior–posterior, dorsal–ventral and medial– lateral axis. Specifically, neural development is also of great clinical relevance because several human neuropsychiatric disorders such as schizophrenia, autism disorders or drug addiction and also brain malformations are thought to have neurodevelopmental origins, i.e. pathogenesis initiates during childhood and adolescence. Impacts during early neurodevelopment might also predispose to late-onset neurodegenerative disorders, such as Parkinson’s disease. The neural tube develops from its precursor tissue, the neural plate, in a patterning process that is determined by compartmentalization into morphogenetic units, the action of local signaling centers and a well-defined and locally restricted expression of genes and their interactions. While public databases provide gene expression data with spatio-temporal resolution, they usually neglect the genetic interactions that govern neural development. Here, we introduce Mouse IDGenes, a reference database for genetic interactions in the developing mouse brain. The database is highly curated and offers detailed information about gene expressions and the genetic interactions at the developing mid-/hindbrain boundary. To showcase the predictive power of interaction data, we infer new Wnt/β-catenin target genes by machine learning and validate one of them experimentally. The database is updated regularly. Moreover, it can easily be extended by the research community. Mouse IDGenes will contribute as an important resource to the research on mouse brain development, not exclusively by offering data retrieval, but also by allowing data input. Database URL: http://mouseidgenes.helmholtz-muenchen.de. PMID:25145340

  2. RE1 silencing transcription factor/neuron-restrictive silencing factor regulates expansion of adult mouse subventricular zone-derived neural stem/progenitor cells in vitro.

    PubMed

    Soldati, Chiara; Caramanica, Pasquale; Burney, Matthew J; Toselli, Camilla; Bithell, Angela; Augusti-Tocco, Gabriella; Stanton, Lawrence W; Biagioni, Stefano; Buckley, Noel J; Cacci, Emanuele

    2015-08-01

    Adult neural stem cell (aNSC) activity is tuned by external stimuli through the recruitment of transcription factors. This study examines the RE1 silencing transcription factor (REST) in neural stem/progenitor cells isolated from the subventricular zone of adult mouse brain and provides the first extensive characterization of REST-mediated control of the cellular and molecular properties. This study shows that REST knockdown affects the capacity of progenitor cells to generate neurospheres, reduces cell proliferation, and triggers cell differentiation despite the presence of growth factors. Genome- and transcriptome-wide analyses show that REST binding sites are significantly enriched in genes associated with synaptic transmission and nervous system development and function. Seeking candidate regulators of aNSC function, this study identifies a member of the bone morphogenetic protein (BMP) family, BMP6, the mRNA and protein of which increased after REST knockdown. The results of this study extend previous findings, demonstrating a reciprocal control of REST expression by BMPs. Administration of exogenous BMP6 inhibits aNSC proliferation and induces the expression of the astrocytic marker glial fibrillary acidic protein, highlighting its antimitogenic and prodifferentiative effects. This study suggests that BMP6 produced in a REST-regulated manner together with other signals can contribute to regulation of NSC maintenance and fate. PMID:25691247

  3. Attenuation of Mouse Melanoma by A/C Magnetic Field after Delivery of Bi-Magnetic Nanoparticles by Neural Progenitor Cells

    PubMed Central

    Rachakatla, Raja Shekar; Balivada, Sivasai; Seo, Gwi-Moon; Myers, Carl B; Wang, Hongwang; Samarakoon, Thilani N.; Dani, Raj; Pyle, Marla; Kroh, Franklin O.; Walker, Brandon; Leaym, Xiaoxuan; Koper, Olga B.; Chikan, Viktor; Bossmann, Stefan H.; Tamura, Masaaki; Troyer, Deryl L.

    2010-01-01

    Localized magnetic hyperthermia as a treatment modality for cancer has generated renewed interest, particularly if it can be targeted to the tumor site. We examined whether tumor-tropic neural progenitor cells (NPCs) could be utilized as cell delivery vehicles for achieving preferential accumulation of core/shell iron/iron oxide magnetic nanoparticles (MNPs) within a mouse model of melanoma. We developed aminosiloxane-porphyrin functionalized MNPs, evaluated cell viability and loading efficiency, and transplanted neural progenitor cells loaded with this cargo into mice with melanoma. NPCs were efficiently loaded with core/shell Fe/Fe3O4 MNPs with minimal cytotoxicity; the MNPs accumulated as aggregates in the cytosol. The NPCs loaded with MNPs could travel to subcutaneous melanomas, and after A/C (alternating current) magnetic field (AMF) exposure, the targeted delivery of MNPs by the cells resulted in a measurable regression of the tumors. The tumor attenuation was significant (p<0.05) a short time (24 hours) after the last of three AMF exposures. PMID:21058696

  4. A Perturbed MicroRNA Expression Pattern Characterizes Embryonic Neural Stem Cells Derived from a Severe Mouse Model of Spinal Muscular Atrophy (SMA).

    PubMed

    Luchetti, Andrea; Ciafrè, Silvia Anna; Murdocca, Michela; Malgieri, Arianna; Masotti, Andrea; Sanchez, Massimo; Farace, Maria Giulia; Novelli, Giuseppe; Sangiuolo, Federica

    2015-01-01

    Spinal muscular atrophy (SMA) is an inherited neuromuscular disorder and the leading genetic cause of death in infants. Despite the disease-causing gene, survival motor neuron (SMN1), encodes a ubiquitous protein, SMN1 deficiency preferentially affects spinal motor neurons (MNs), leaving the basis of this selective cell damage still unexplained. As neural stem cells (NSCs) are multipotent self-renewing cells that can differentiate into neurons, they represent an in vitro model for elucidating the pathogenetic mechanism of neurodegenerative diseases such as SMA. Here we characterize for the first time neural stem cells (NSCs) derived from embryonic spinal cords of a severe SMNΔ7 SMA mouse model. SMNΔ7 NSCs behave as their wild type (WT) counterparts, when we consider neurosphere formation ability and the expression levels of specific regional and self-renewal markers. However, they show a perturbed cell cycle phase distribution and an increased proliferation rate compared to wild type cells. Moreover, SMNΔ7 NSCs are characterized by the differential expression of a limited number of miRNAs, among which miR-335-5p and miR-100-5p, reduced in SMNΔ7 NSCs compared to WT cells. We suggest that such miRNAs may be related to the proliferation differences characterizing SMNΔ7 NSCs, and may be potentially involved in the molecular mechanisms of SMA. PMID:26258776

  5. A Perturbed MicroRNA Expression Pattern Characterizes Embryonic Neural Stem Cells Derived from a Severe Mouse Model of Spinal Muscular Atrophy (SMA)

    PubMed Central

    Luchetti, Andrea; Ciafrè, Silvia Anna; Murdocca, Michela; Malgieri, Arianna; Masotti, Andrea; Sanchez, Massimo; Farace, Maria Giulia; Novelli, Giuseppe; Sangiuolo, Federica

    2015-01-01

    Spinal muscular atrophy (SMA) is an inherited neuromuscular disorder and the leading genetic cause of death in infants. Despite the disease-causing gene, survival motor neuron (SMN1), encodes a ubiquitous protein, SMN1 deficiency preferentially affects spinal motor neurons (MNs), leaving the basis of this selective cell damage still unexplained. As neural stem cells (NSCs) are multipotent self-renewing cells that can differentiate into neurons, they represent an in vitro model for elucidating the pathogenetic mechanism of neurodegenerative diseases such as SMA. Here we characterize for the first time neural stem cells (NSCs) derived from embryonic spinal cords of a severe SMNΔ7 SMA mouse model. SMNΔ7 NSCs behave as their wild type (WT) counterparts, when we consider neurosphere formation ability and the expression levels of specific regional and self-renewal markers. However, they show a perturbed cell cycle phase distribution and an increased proliferation rate compared to wild type cells. Moreover, SMNΔ7 NSCs are characterized by the differential expression of a limited number of miRNAs, among which miR-335-5p and miR-100-5p, reduced in SMNΔ7 NSCs compared to WT cells. We suggest that such miRNAs may be related to the proliferation differences characterizing SMNΔ7 NSCs, and may be potentially involved in the molecular mechanisms of SMA. PMID:26258776

  6. Protease-activated receptor-1 negatively regulates proliferation of neural stem/progenitor cells derived from the hippocampal dentate gyrus of the adult mouse.

    PubMed

    Tanaka, Masayuki; Yoneyama, Masanori; Shiba, Tatsuo; Yamaguchi, Taro; Ogita, Kiyokazu

    2016-07-01

    Thrombin-activated protease-activated receptor (PAR)-1 regulates the proliferation of neural cells following brain injury. To elucidate the involvement of PAR-1 in the neurogenesis that occurs in the adult hippocampus, we examined whether PAR-1 regulated the proliferation of neural stem/progenitor cells (NPCs) derived from the murine hippocampal dentate gyrus. NPC cultures expressed PAR-1 protein and mRNA encoding all subtypes of PAR. Direct exposure of the cells to thrombin dramatically attenuated the cell proliferation without causing cell damage. This thrombin-induced attenuation was almost completely abolished by the PAR antagonist RWJ 56110, as well as by dabigatran and 4-(2-aminoethyl)benzenesulfonyl fluoride (AEBSF), which are selective and non-selective thrombin inhibitors, respectively. Expectedly, the PAR-1 agonist peptide (AP) SFLLR-NH2 also attenuated the cell proliferation. The cell proliferation was not affected by the PAR-1 negative control peptide RLLFT-NH2, which is an inactive peptide for PAR-1. Independently, we determined the effect of in vivo treatment with AEBSF or AP on hippocampal neurogenesis in the adult mouse. The administration of AEBSF, but not that of AP, significantly increased the number of newly-generated cells in the hippocampal subgranular zone. These data suggest that PAR-1 negatively regulated adult neurogenesis in the hippocampus by inhibiting the proliferative activity of the NPCs. PMID:27426918

  7. Comparison of gene expression regulation in mouse- and human embryonic stem cell assays during neural differentiation and in response to valproic acid exposure.

    PubMed

    Schulpen, Sjors H W; Theunissen, Peter T; Pennings, Jeroen L A; Piersma, Aldert H

    2015-08-15

    Embryonic stem cell tests (EST) are considered promising alternative assays for developmental toxicity testing. Classical mouse derived assays (mEST) are being replaced by human derived assays (hEST), in view of their relevance for human hazard assessment. We have compared mouse and human neural ESTn assays for neurodevelopmental toxicity as to regulation of gene expression during cell differentiation in both assays. Commonalities were observed in a range of neurodevelopmental genes and gene ontology (GO) terms. The mESTn showed a higher specificity in neurodevelopment than the hESTn, which may in part be caused by necessary differences in test protocols. Moreover, gene expression responses to the anticonvulsant and human teratogen valproic acid were compared. Both assays detected pharmacological and neurodevelopmental gene sets regulated by valproic acid. Common significant expression changes were observed in a subset of homologous neurodevelopmental genes. We suggest that these genes and related GO terms may provide good candidates for robust biomarkers of neurodevelopmental toxicity in hESTn. PMID:26072468

  8. Endogenous microglia regulate development of embryonic cortical precursor cells.

    PubMed

    Antony, Joseph M; Paquin, Annie; Nutt, Stephen L; Kaplan, David R; Miller, Freda D

    2011-03-01

    Microglia play important roles in the damaged or degenerating adult nervous system. However, the role of microglia in embryonic brain development is still largely uncharacterized. Here we show that microglia are present in regions of the developing brain that contain neural precursors from E11 onward. To determine whether these microglia are important for neural precursor maintenance or self-renewal, we cultured embryonic neural precursors from the cortex of PU.1(-/-) mice, which we show lack resident microglia during embryogenesis. Cell survival and neurogenesis were similar in cultures from PU.1(-/-) vs. PU.1(+/+) mice, but precursor proliferation and astrogenesis were both reduced. Cortical precursors depleted of microglia also displayed decreased precursor proliferation and astrogenesis, and these deficits could be rescued when microglia were added back to the cultures. Moreover, when the number of microglia present in cortical precursor cultures was increased above normal levels, astrogenesis but not neurogenesis was increased. Together these results demonstrate that microglia present within the embryonic neural precursor niche can regulate neural precursor development and suggest that alterations in microglial number as a consequence of genetic or pathological events could perturb neural development by directly affecting embryonic neural precursors. PMID:21259316

  9. EGF–FGF{sub 2} stimulates the proliferation and improves the neuronal commitment of mouse epidermal neural crest stem cells (EPI-NCSCs)

    SciTech Connect

    Bressan, Raul Bardini; Melo, Fernanda Rosene; Almeida, Patricia Alves; Bittencourt, Denise Avani; Visoni, Silvia; Jeremias, Talita Silva; Costa, Ana Paula; Leal, Rodrigo Bainy; Trentin, Andrea Gonçalves

    2014-09-10

    Epidermal neural crest stem cells (EPI-NCSCs), which reside in the bulge of hair follicles, are attractive candidates for several applications in cell therapy, drug screening and tissue engineering. As suggested remnants of the embryonic neural crest (NC) in an adult location, EPI-NCSCs are able to generate a wide variety of cell types and are readily accessible by a minimally invasive procedure. Since the combination of epidermal growth factor (EGF) and fibroblast growth factor type 2 (FGF{sub 2}) is mitogenic and promotes the neuronal commitment of various stem cell populations, we examined its effects in the proliferation and neuronal potential of mouse EPI-NCSCs. By using a recognized culture protocol of bulge whiskers follicles, we were able to isolate a population of EPI-NCSCs, characterized by the migratory potential, cell morphology and expression of phenotypic markers of NC cells. EPI-NCSCs expressed neuronal, glial and smooth muscle markers and exhibited the NC-like fibroblastic morphology. The treatment with the combination EGF and FGF{sub 2}, however, increased their proliferation rate and promoted the acquisition of a neuronal-like morphology accompanied by reorganization of neural cytoskeletal proteins βIII-tubulin and nestin, as well as upregulation of the pan neuronal marker βIII-tubulin and down regulation of the undifferentiated NC, glial and smooth muscle cell markers. Moreover, the treatment enhanced the response of EPI-NCSCs to neurogenic stimulation, as evidenced by induction of GAP43, and increased expression of Mash-1 in neuron-like cell, both neuronal-specific proteins. Together, the results suggest that the combination of EGF–FGF2 stimulates the proliferation and improves the neuronal potential of EPI-NCSCs similarly to embryonic NC cells, ES cells and neural progenitor/stem cells of the central nervous system and highlights the advantage of using EGF–FGF{sub 2} in neuronal differentiation protocols. - Highlights: • EPI

  10. Differences in the spatiotemporal expression and epistatic gene regulation of the mesodiencephalic dopaminergic precursor marker PITX3 during chicken and mouse development.

    PubMed

    Klafke, Ruth; Prem Anand, A Alwin; Wurst, Wolfgang; Prakash, Nilima; Wizenmann, Andrea

    2016-02-15

    Mesodiencephalic dopaminergic (mdDA) neurons are located in the ventral mesencephalon and caudal diencephalon of all tetrapod species studied so far. They are the most prominent DA neuronal population and are implicated in control and modulation of motor, cognitive and rewarding/affective behaviors. Their degeneration or dysfunction is intimately linked to several neurological and neuropsychiatric human diseases. To gain further insights into their generation, we studied spatiotemporal expression patterns and epistatic interactions in chick embryos of selected marker genes and signaling pathways associated with mdDA neuron development in mouse. We detected striking differences in the expression patterns of the chick orthologs of the mouse mdDA marker genes Pitx3 and Aldh1a1, which suggests important differences between the species in the generation/generating of these cells. We also discovered that the sonic hedgehog signaling pathway is both necessary and sufficient for the induction of ectopic PITX3 expression in chick mesencephalon downstream of WNT9A-induced LMX1a transcription. These aspects of early chicken development resemble the ontogeny of zebrafish diencephalic DA neuronal populations, and suggest a divergence between birds and mammals during evolution. PMID:26755703

  11. Csn3 Gene Is Regulated by All-Trans Retinoic Acid during Neural Differentiation in Mouse P19 Cells

    PubMed Central

    Komori, Rie; Kobayashi, Takanobu; Matsuo, Hikaru; Kino, Katsuhito; Miyazawa, Hiroshi

    2013-01-01

    κ-Casein (CSN3) is known to play an essential role in controlling the stability of the milk micelles. We found that the expression of Csn3 was induced by all-trans retinoic acid (ATRA) during neural differentiation in P19 embryonal carcinoma cells from our study using DNA microarray. In this paper, we describe the detailed time course of Csn3 expression and the induction mechanism of Csn3 transcription activation in this process. The Csn3 expression was induced rapidly and transiently within 24 h of ATRA treatment. Retinoic acid receptor (RAR)-specific agonists were used in expression analysis to identify the RAR subtype involved upregulation of Csn3; a RARα-specific agonist mimicked the effects of ATRA on induction of Csn3 expression. Therefore, RARα may be the RAR subtype mediating the effects of ATRA on the induction of Csn3 gene transcription in this differentiation-promoting process of P19 cells. We found that the promoter region of Csn3 contained a typical consensus retinoic acid response element (RARE), and this RARE was necessary for ATRA-dependent transcriptional regulation. We confirmed that RARα bound to this RARE sequence in P19 cells. These findings indicated that the Csn3 expression is upregulated via ATRA-bound RARα and binding of this receptor to the RARE in the Csn3 promoter region. This will certainly serve as a first step forward unraveling the mysteries of induction of Csn3 in the process of neural differentiation. PMID:23613978

  12. Ganglioside GD3 Is Required for Neurogenesis and Long-Term Maintenance of Neural Stem Cells in the Postnatal Mouse Brain

    PubMed Central

    Wang, Jing; Cheng, Allison; Wakade, Chandramohan

    2014-01-01

    The maintenance of a neural stem cell (NSC) population in mammalian postnatal and adult life is crucial for continuous neurogenesis and neural repair. However, the molecular mechanism of how NSC populations are maintained remains unclear. Gangliosides are important cellular membrane components in the nervous system. We previously showed that ganglioside GD3 plays a crucial role in the maintenance of the self-renewal capacity of NSCs in vitro. Here, we investigated its role in postnatal and adult neurogenesis in GD3-synthase knock-out (GD3S-KO) and wild-type mice. GD3S-KO mice with deficiency in GD3 and the downstream b-series gangliosides showed a progressive loss of NSCs both at the SVZ and the DG of the hippocampus. The decrease of NSC populations in the GD3S-KO mice resulted in impaired neurogenesis at the granular cell layer of the olfactory bulb and the DG in the adult. In addition, defects of the self-renewal capacity and radial glia-like stem cell outgrowth of postnatal GD3S-KO NSCs could be rescued by restoration of GD3 expression in these cells. Our study demonstrates that the b-series gangliosides, especially GD3, play a crucial role in the long-term maintenance NSC populations in postnatal mouse brain. Moreover, the impaired neurogenesis in the adult GD3S-KO mice led to depression-like behaviors. Thus, our results provide convincing evidence linking b-series gangliosides deficiency and neurogenesis defects to behavioral deficits, and support a crucial role of gangliosides in the long-term maintenance of NSCs in adult mice. PMID:25297105

  13. Histamine up-regulates fibroblast growth factor receptor 1 and increases FOXP2 neurons in cultured neural precursors by histamine type 1 receptor activation: conceivable role of histamine in neurogenesis during cortical development in vivo

    PubMed Central

    2013-01-01

    Background During rat development, histamine (HA) is one of the first neuroactive molecules to appear in the brain, reaching its maximal value at embryonic day 14, a period when neurogenesis of deep layers is occurring in the cerebral cortex, suggesting a role of this amine in neuronal specification. We previously reported, using high-density cerebrocortical neural precursor cultures, that micromolar HA enhanced the effect of fibroblast growth factor (FGF)-2 on proliferation, and that HA increased neuronal differentiation, due to HA type 1 receptor (H1R) activation. Results Clonal experiments performed here showed that HA decreased colony size and caused a significant increase in the percentage of clones containing mature neurons through H1R stimulation. In proliferating precursors, we studied whether HA activates G protein-coupled receptors linked to intracellular calcium increases. Neural cells presented an increase in cytoplasmic calcium even in the absence of extracellular calcium, a response mediated by H1R. Since FGF receptors (FGFRs) are known to be key players in cell proliferation and differentiation, we determined whether HA modifies the expression of FGFRs1-4 by using RT-PCR. An important transcriptional increase in FGFR1 was elicited after H1R activation. We also tested whether HA promotes differentiation specifically to neurons with molecular markers of different cortical layers by immunocytochemistry. HA caused significant increases in cells expressing the deep layer neuronal marker FOXP2; this induction of FOXP2-positive neurons elicited by HA was blocked by the H1R antagonist chlorpheniramine in vitro. Finally, we found a notable decrease in FOXP2+ cortical neurons in vivo, when chlorpheniramine was infused in the cerebral ventricles through intrauterine injection. Conclusion These results show that HA, by activating H1R, has a neurogenic effect in clonal conditions and suggest that intracellular calcium elevation and transcriptional up

  14. Dynamic Re-wiring of Neural Circuits in the Motor Cortex in Mouse Models of Parkinson's Disease

    PubMed Central

    Lalchandani, Rupa R.; Cui, Yuting; Shu, Yu; Xu, Tonghui; Ding, Jun B.

    2015-01-01

    SUMMARY Dynamic adaptations in synaptic plasticity are critical for learning new motor skills and maintaining memory throughout life, which rapidly decline with Parkinson's disease (PD). Plasticity in the motor cortex is important for acquisition and maintenance of novel motor skills, but how the loss of dopamine in PD leads to disrupted structural and functional plasticity in the motor cortex is not well understood. Here, we utilized mouse models of PD and 2-photon imaging to show that dopamine depletion resulted in structural changes in the motor cortex. We further discovered that dopamine D1 and D2 receptor signaling were linked to selectively and distinctly regulating these aberrant changes in structural and functional plasticity. Our findings suggest that both D1 and D2 receptor signaling regulate motor cortex plasticity, and loss of dopamine results in atypical synaptic adaptations that may contribute to the impairment of motor performance and motor memory observed in PD. PMID:26237365

  15. beta. -Amyloid precursor protein of Alzheimer disease occurs as 110- to 135-kilodalton membrane-associated proteins in neural and nonneural tissues

    SciTech Connect

    Selkoe, D.J.; Podlisny, M.B.; Joachim, C.L.; Vickers, E.A.; Lee, G.; Fritz, L.C.; Oltersdorf, T. )

    1988-10-01

    Progressive cerebral deposition of extracellular filaments composed of the {beta}-amyloid protein ({beta}AP) is a constant feature of Alzheimer disease (AD). Since the gene on chromosome 21 encoding the {beta}AP precursor ({beta}APP) is not known to be altered in AD, transcriptional or posttranslational changes may underlie accelerated {beta}AP deposition. Using two antibodies to the predicted carboxyl terminus of {beta}APP, the authors have identified the native {beta}APP in brain and nonneural human tissues as a 110- to 135-kDa protein complex that is insoluble in buffer and found in various membrane-rich subcellular fractions. These proteins are relatively uniformly distributed in adult brain, abundant in fetal brain, and detected in nonneural tissues that contain {beta}APP mRNA. Similarly sized proteins occur in rat, cow, and monkey brain and in cultured human HL-60 and HeLa cells; the precise patterns in the 110- to 135-kDa range are heterogeneous among various tissues and cell lines. They conclude that the highly conserved {beta}APP molecule occurs in mammalian tissues as a heterogeneous group of membrane-associated proteins of {approx} 120 kDa. Detection of the nonamyloidogenic carboxyl terminus within plaques suggests that proteolytic processing of the {beta}APP into insoluble filaments occurs locally in cortical regions that develop {beta}-amyloid deposits with age.

  16. Baicalein reduces β-amyloid and promotes nonamyloidogenic amyloid precursor protein processing in an Alzheimer’s disease transgenic mouse model

    PubMed Central

    Zhang, She-Qing; Obregon, Demian; Ehrhart, Jared; Deng, Juan; Tian, Jun; Hou, Huayan; Giunta, Brian; Sawmiller, Darrell; Tan, Jun

    2013-01-01

    Baicalein, a flavonoid isolated from the roots of Scutellaria baicalensis, is known to modulate γ-aminobutyric acid (GABA) type A receptors. Given prior reports demonstrating benefits of GABAA modulation for Alzheimer’s disease (AD) treatment, we wished to determine whether this agent might be beneficial for AD. CHO cells engineered to overexpress wild-type amyloid precursor protein (APP), primary culture neuronal cells from AD mice (Tg2576) and AD mice were treated with baicalein. In the cell cultures, baicalein significantly reduced the production of β-amyloid (Aβ) by increasing APP α-processing. These effects were blocked by the GABAA antagonist bicuculline. Likewise, AD mice treated daily with i.p. baicalein for 8 weeks showed enhanced APP α-secretase processing, reduced Aβ production, and reduced AD-like pathology together with improved cognitive performance. Our findings suggest that baicalein promotes nonamyloidogenic processing of APP, thereby reducing Aβ production and improving cognitive performance, by activating GABAA receptors. © 2013 Wiley Periodicals, Inc. PMID:23686791

  17. Foxg1-Cre Mediated Lrp2 Inactivation in the Developing Mouse Neural Retina, Ciliary and Retinal Pigment Epithelia Models Congenital High Myopia

    PubMed Central

    Obry, Antoine; Santin, Mathieu D.; Ben-Yacoub, Sirine; Pâques, Michel; Amsellem-Levera, Sabine; Bribian, Ana; Simonutti, Manuel; Augustin, Sébastien; Debeir, Thomas; Sahel, José Alain; Christ, Annabel; de Castro, Fernando; Lehéricy, Stéphane; Cosette, Pascal; Kozyraki, Renata

    2015-01-01

    Myopia is a common ocular disorder generally due to increased axial length of the eye-globe. Its extreme form high myopia (HM) is a multifactorial disease leading to retinal and scleral damage, visual impairment or loss and is an important health issue. Mutations in the endocytic receptor LRP2 gene result in Donnai-Barrow (DBS) and Stickler syndromes, both characterized by HM. To clearly establish the link between Lrp2 and congenital HM we inactivated Lrp2 in the mouse forebrain including the neural retina and the retinal and ciliary pigment epithelia. High resolution in vivo MRI imaging and ophthalmological analyses showed that the adult Lrp2-deficient eyes were 40% longer than the control ones mainly due to an excessive elongation of the vitreal chamber. They had an apparently normal intraocular pressure and developed chorioretinal atrophy and posterior scleral staphyloma features reminiscent of human myopic retinopathy. Immunomorphological and ultrastructural analyses showed that increased eye lengthening was first observed by post-natal day 5 (P5) and that it was accompanied by a rapid decrease of the bipolar, photoreceptor and retinal ganglion cells, and eventually the optic nerve axons. It was followed by scleral thinning and collagen fiber disorganization, essentially in the posterior pole. We conclude that the function of LRP2 in the ocular tissues is necessary for normal eye growth and that the Lrp2-deficient eyes provide a unique tool to further study human HM. PMID:26107939

  18. Polysialic acid enters the cell nucleus attached to a fragment of the neural cell adhesion molecule NCAM to regulate the circadian rhythm in mouse brain.

    PubMed

    Westphal, Nina; Kleene, Ralf; Lutz, David; Theis, Thomas; Schachner, Melitta

    2016-07-01

    In the mammalian nervous system, the neural cell adhesion molecule NCAM is the major carrier of the glycan polymer polysialic acid (PSA) which confers important functions to NCAM's protein backbone. PSA attached to NCAM contributes not only to cell migration, neuritogenesis, synaptic plasticity, and behavior, but also to regulation of the circadian rhythm by yet unknown molecular mechanisms. Here, we show that a PSA-carrying transmembrane NCAM fragment enters the nucleus after stimulation of cultured neurons with surrogate NCAM ligands, a phenomenon that depends on the circadian rhythm. Enhanced nuclear import of the PSA-carrying NCAM fragment is associated with altered expression of clock-related genes, as shown by analysis of cultured neuronal cells deprived of PSA by specific enzymatic removal. In vivo, levels of nuclear PSA in different mouse brain regions depend on the circadian rhythm and clock-related gene expression in suprachiasmatic nucleus and cerebellum is affected by the presence of PSA-carrying NCAM in the cell nucleus. Our conceptually novel observations reveal that PSA attached to a transmembrane proteolytic NCAM fragment containing part of the extracellular domain enters the cell nucleus, where PSA-carrying NCAM contributes to the regulation of clock-related gene expression and of the circadian rhythm. PMID:27236020

  19. Heptanoate as a neural fuel: energetic and neurotransmitter precursors in normal and glucose transporter I-deficient (G1D) brain

    PubMed Central

    Marin-Valencia, Isaac; Good, Levi B; Ma, Qian; Malloy, Craig R; Pascual, Juan M

    2013-01-01

    It has been postulated that triheptanoin can ameliorate seizures by supplying the tricarboxylic acid cycle with both acetyl-CoA for energy production and propionyl-CoA to replenish cycle intermediates. These potential effects may also be important in other disorders associated with impaired glucose metabolism because glucose supplies, in addition to acetyl-CoA, pyruvate, which fulfills biosynthetic demands via carboxylation. In patients with glucose transporter type I deficiency (G1D), ketogenic diet fat (a source only of acetyl-CoA) reduces seizures, but other symptoms persist, providing the motivation for studying heptanoate metabolism. In this work, metabolism of infused [5,6,7-13C3]heptanoate was examined in the normal mouse brain and in G1D by 13C-nuclear magnetic resonance spectroscopy, gas chromatography-mass spectrometry (GC-MS), and liquid chromatography-mass spectrometry (LC-MS). In both groups, plasma glucose was enriched in 13C, confirming gluconeogenesis from heptanoate. Acetyl-CoA and glutamine levels became significantly higher in the brain of G1D mice relative to normal mice. In addition, brain glutamine concentration and 13C enrichment were also greater when compared with glutamate in both animal groups, suggesting that heptanoate and/or C5 ketones are primarily metabolized by glia. These results enlighten the mechanism of heptanoate metabolism in the normal and glucose-deficient brain and encourage further studies to elucidate its potential antiepileptic effects in disorders of energy metabolism. PMID:23072752

  20. Heptanoate as a neural fuel: energetic and neurotransmitter precursors in normal and glucose transporter I-deficient (G1D) brain.

    PubMed

    Marin-Valencia, Isaac; Good, Levi B; Ma, Qian; Malloy, Craig R; Pascual, Juan M

    2013-02-01

    It has been postulated that triheptanoin can ameliorate seizures by supplying the tricarboxylic acid cycle with both acetyl-CoA for energy production and propionyl-CoA to replenish cycle intermediates. These potential effects may also be important in other disorders associated with impaired glucose metabolism because glucose supplies, in addition to acetyl-CoA, pyruvate, which fulfills biosynthetic demands via carboxylation. In patients with glucose transporter type I deficiency (G1D), ketogenic diet fat (a source only of acetyl-CoA) reduces seizures, but other symptoms persist, providing the motivation for studying heptanoate metabolism. In this work, metabolism of infused [5,6,7-(13)C(3)]heptanoate was examined in the normal mouse brain and in G1D by (13)C-nuclear magnetic resonance spectroscopy, gas chromatography-mass spectrometry (GC-MS), and liquid chromatography-mass spectrometry (LC-MS). In both groups, plasma glucose was enriched in (13)C, confirming gluconeogenesis from heptanoate. Acetyl-CoA and glutamine levels became significantly higher in the brain of G1D mice relative to normal mice. In addition, brain glutamine concentration and (13)C enrichment were also greater when compared with glutamate in both animal groups, suggesting that heptanoate and/or C5 ketones are primarily metabolized by glia. These results enlighten the mechanism of heptanoate metabolism in the normal and glucose-deficient brain and encourage further studies to elucidate its potential antiepileptic effects in disorders of energy metabolism. PMID:23072752

  1. Global gene expression profiling in mouse plasma cell tumor precursor and bystander cells reveals potential intervention targets for plasma cell neoplasia.

    PubMed

    LeGrand, Jason; Park, Eun Sung; Wang, Hongyang; Gupta, Shalu; Owens, James D; Nelson, Patrick J; DuBois, Wendy; Bair, Thomas; Janz, Siegfried; Mushinski, J Frederic

    2012-01-26

    Tumor progression usually proceeds through several sequential stages, any of which could be targets for interrupting the progression process if one understood these steps at the molecular level. We extracted nascent plasma cell tumor (PCT) cells from within inflammatory oil granulomas (OG) isolated from IP pristane-injected BALB/c.iMyc(Eμ) mice at 5 different time points during tumor progression. We used laser capture microdissection to collect incipient PCT cells and analyzed their global gene expression on Affymetrix Mouse Genome 430A microarrays. Two independent studies were performed with different sets of mice. Analysis of the expression data used ANOVA and Bayesian estimation of temporal regulation. Genetic pathway analysis was performed using MetaCore (GeneGo) and IPA (Ingenuity). The gene expression profiles of PCT samples and those of undissected OG samples from adjacent sections showed that different genes and pathways were mobilized in the tumor cells during tumor progression, compared with their stroma. Our analysis implicated several genetic pathways in PCT progression, including biphasic (up- and then down-regulation) of the Spp1/osteopontin-dependent network and up-regulation of mRNA translation/protein synthesis. The latter led to a biologic validation study that showed that the AMPK-activating diabetes drug, metformin, was a potent specific PCT inhibitor in vitro. PMID:22147894

  2. Neural Stem Cell Gene Therapy Ameliorates Pathology and Function in a Mouse Model of Globoid Cell Leukodystrophy

    PubMed Central

    Neri, Margherita; Ricca, Alessandra; di Girolamo, Ilaria; Alcala'-Franco, Beatriz; Cavazzin, Chiara; Orlacchio, Aldo; Martino, Sabata; Naldini, Luigi; Gritti, Angela

    2011-01-01

    Murine neural stem cells (mNSCs), either naive or genetically modified to express supranormal levels of β-galactocerebrosidase (GALC), were transplanted into the brain of Twitcher mice, a murine model of globoid cell leukodystrophy, a severe sphingolipidosis. Cells engrafted long-term into the host cytoarchitecture, producing functional GALC. Levels of enzyme activity in brain and spinal cord tissues were enhanced when GALC-overexpressing NSC were used. Enzymatic correction correlated with reduced tissue storage, decreased activation of astroglia and microglia, delayed onset of symptoms, and longer lifespan. Mechanisms underlying the therapeutic effect of mNSC included widespread enzyme distribution, cross-correction of host cells, anti-inflammatory activity, and neuroprotection. Similar cell engraftment and metabolic correction were reproduced using human NSC. Thus, NSC gene therapy rapidly reconstitutes sustained and long-lasting enzyme activity in central nervous system tissues. Combining this approach with treatments targeting the systemic disease associated with leukodystrophies may provide significant therapeutic benefit. Stem Cells 2011;29:1559–1571 PMID:21809420

  3. Neural stem cell transplantation at critical period improves learning and memory through restoring synaptic impairment in Alzheimer's disease mouse model.

    PubMed

    Kim, J A; Ha, S; Shin, K Y; Kim, S; Lee, K J; Chong, Y H; Chang, K-A; Suh, Y-H

    2015-01-01

    Alzheimer's disease (AD) is characterized by neuronal loss in several regions of the brain. Recent studies have suggested that stem cell transplantation could serve as a potential therapeutic strategy to halt or ameliorate the inexorable disease progression. However, the optimal stage of the disease for stem cell transplantation to have a therapeutic effect has yet to be determined. Here, we demonstrated that transplantation of neural stem cells into 12-month-old Tg2576 brains markedly improved both cognitive impairments and neuropathological features by reducing β-amyloid processing and upregulating clearance of β-amyloid, secretion of anti-inflammatory cytokines, endogenous neurogenesis, as well as synapse formation. In contrast, the stem cell transplantation did not recover cognitive dysfunction and β-amyloid neuropathology in Tg2576 mice aged 15 months when the memory loss is manifest. Overall, this study underscores that stem cell therapy at optimal time frame is crucial to obtain maximal therapeutic effects that can restore functional deficits or stop the progression of AD. PMID:26086962

  4. High MRI performance fluorescent mesoporous silica-coated magnetic nanoparticles for tracking neural progenitor cells in an ischemic mouse model

    NASA Astrophysics Data System (ADS)

    Zhang, Lu; Wang, Yao; Tang, Yaohui; Jiao, Zheng; Xie, Chengying; Zhang, Haijiao; Gu, Ping; Wei, Xunbin; Yang, Guo-Yuan; Gu, Hongchen; Zhang, Chunfu

    2013-05-01

    Multifunctional probes with high MRI sensitivity and high efficiency for cell labeling are desirable for MR cell imaging. Herein, we have fabricated fluorescent mesoporous silica-coated superparamagnetic iron oxide nanoparticles (fmSiO4@SPIONs) for neural progenitor cell (C17.2) MR imaging. FmSiO4@SPIONs were discrete and uniform in size, and had a clear core-shell structure. The magnetic core size was about 10 nm and the fluorescent mesoporous silica coating layer was around 20 nm. Compared with fluorescent dense silica-coated SPIONs (fdSiO4@SPIONs) with a similar size, fmSiO4@SPIONs demonstrated higher MR sensitivity and cell labeling efficiency. When implanted into the right hemisphere of stroke mice, contralateral to the ischemic territory, a small amount of labeled cells were able to be tracked migrating to the lesion sites using a clinical MRI scanner (3 T). More impressively, even when administered intravenously, the labeled cells could also be monitored homing to the ischemic area. MRI observations were corroborated by histological studies of the brain tissues. Our study demonstrated that fmSiO4@SPIONs are highly effective for cell imaging and hold great promise for MRI cell tracking in future.Multifunctional probes with high MRI sensitivity and high efficiency for cell labeling are desirable for MR cell imaging. Herein, we have fabricated fluorescent mesoporous silica-coated superparamagnetic iron oxide nanoparticles (fmSiO4@SPIONs) for neural progenitor cell (C17.2) MR imaging. FmSiO4@SPIONs were discrete and uniform in size, and had a clear core-shell structure. The magnetic core size was about 10 nm and the fluorescent mesoporous silica coating layer was around 20 nm. Compared with fluorescent dense silica-coated SPIONs (fdSiO4@SPIONs) with a similar size, fmSiO4@SPIONs demonstrated higher MR sensitivity and cell labeling efficiency. When implanted into the right hemisphere of stroke mice, contralateral to the ischemic territory, a small amount of

  5. Noise-induced precursors of state transitions in the stochastic Wilson-cowan model.

    PubMed

    Negahbani, Ehsan; Steyn-Ross, D Alistair; Steyn-Ross, Moira L; Wilson, Marcus T; Sleigh, Jamie W

    2015-01-01

    The Wilson-Cowan neural field equations describe the dynamical behavior of a 1-D continuum of excitatory and inhibitory cortical neural aggregates, using a pair of coupled integro-differential equations. Here we use bifurcation theory and small-noise linear stochastics to study the range of a phase transitions-sudden qualitative changes in the state of a dynamical system emerging from a bifurcation-accessible to the Wilson-Cowan network. Specifically, we examine saddle-node, Hopf, Turing, and Turing-Hopf instabilities. We introduce stochasticity by adding small-amplitude spatio-temporal white noise, and analyze the resulting subthreshold fluctuations using an Ornstein-Uhlenbeck linearization. This analysis predicts divergent changes in correlation and spectral characteristics of neural activity during close approach to bifurcation from below. We validate these theoretical predictions using numerical simulations. The results demonstrate the role of noise in the emergence of critically slowed precursors in both space and time, and suggest that these early-warning signals are a universal feature of a neural system close to bifurcation. In particular, these precursor signals are likely to have neurobiological significance as early warnings of impending state change in the cortex. We support this claim with an analysis of the in vitro local field potentials recorded from slices of mouse-brain tissue. We show that in the period leading up to emergence of spontaneous seizure-like events, the mouse field potentials show a characteristic spectral focusing toward lower frequencies concomitant with a growth in fluctuation variance, consistent with critical slowing near a bifurcation point. This observation of biological criticality has clear implications regarding the feasibility of seizure prediction. PMID:25859420

  6. Formate supplementation enhances folate-dependent nucleotide biosynthesis and prevents spina bifida in a mouse model of folic acid-resistant neural tube defects.

    PubMed

    Sudiwala, Sonia; De Castro, Sandra C P; Leung, Kit-Yi; Brosnan, John T; Brosnan, Margaret E; Mills, Kevin; Copp, Andrew J; Greene, Nicholas D E

    2016-07-01

    The curly tail mouse provides a model for neural tube defects (spina bifida and exencephaly) that are resistant to prevention by folic acid. The major ct gene, responsible for spina bifida, corresponds to a hypomorphic allele of grainyhead-like 3 (Grhl3) but the frequency of NTDs is strongly influenced by modifiers in the genetic background. Moreover, exencephaly in the curly tail strain is not prevented by reinstatement of Grhl3 expression. In the current study we found that expression of Mthfd1L, encoding a key component of mitochondrial folate one-carbon metabolism (FOCM), is significantly reduced in ct/ct embryos compared to a partially congenic wild-type strain. This expression change is not attributable to regulation by Grhl3 or the genetic background at the Mthfd1L locus. Mitochondrial FOCM provides one-carbon units as formate for FOCM reactions in the cytosol. We found that maternal supplementation with formate prevented NTDs in curly tail embryos and also resulted in increased litter size. Analysis of the folate profile of neurulation-stage embryos showed that formate supplementation resulted in an increased proportion of formyl-THF and THF but a reduction in proportion of 5-methyl THF. In contrast, THF decreased and 5-methyl THF was relatively more abundant in the liver of supplemented dams than in controls. In embryos cultured through the period of spinal neurulation, incorporation of labelled thymidine and adenine into genomic DNA was suppressed by supplemental formate, suggesting that de novo folate-dependent biosynthesis of nucleotides (thymidylate and purines) was enhanced. We hypothesise that reduced Mthfd1L expression may contribute to susceptibility to NTDs in the curly tail strain and that formate acts as a one-carbon donor to prevent NTDs. PMID:26924399

  7. A 3.7 kb Fragment of the Mouse Scn10a Gene Promoter Directs Neural Crest But Not Placodal Lineage EGFP Expression in a Transgenic Animal

    PubMed Central

    Lu, Van B.; Ikeda, Stephen R.

    2015-01-01

    Under physiological conditions, the voltage-gated sodium channel Nav1.8 is expressed almost exclusively in primary sensory neurons. The mechanism restricting Nav1.8 expression is not entirely clear, but we have previously described a 3.7 kb fragment of the Scn10a promoter capable of recapitulating the tissue-specific expression of Nav1.8 in transfected neurons and cell lines (Puhl and Ikeda, 2008). To validate these studies in vivo, a transgenic mouse encoding EGFP under the control of this putative sensory neuron specific promoter was generated and characterized in this study. Approximately 45% of dorsal root ganglion neurons of transgenic mice were EGFP-positive (mean diameter = 26.5 μm). The majority of EGFP-positive neurons bound isolectin B4, although a small percentage (∼10%) colabeled with markers of A-fiber neurons. EGFP expression correlated well with the presence of Nav1.8 transcript (95%), Nav1.8-immunoreactivity (70%), and TTX-R INa (100%), although not all Nav1.8-expressing neurons expressed EGFP. Several cranial sensory ganglia originating from neurogenic placodes, such as the nodose ganglion, failed to express EGFP, suggesting that additional regulatory elements dictate Scn10a expression in placodal-derived sensory neurons. EGFP was also detected in discrete brain regions of transgenic mice. Quantitative PCR and Nav1.8-immunoreactivity confirmed Nav1.8 expression in the amygdala, brainstem, globus pallidus, lateral and paraventricular hypothalamus, and olfactory tubercle. TTX-R INa recorded from EGFP-positive hypothalamic neurons demonstrate the usefulness of this transgenic line to study novel roles of Nav1.8 beyond sensory neurons. Overall, Scn10a-EGFP transgenic mice recapitulate the majority of the Nav1.8 expression pattern in neural crest-derived sensory neurons. PMID:25995484

  8. Sustained Neural Stem Cell-Based Intraocular Delivery of CNTF Attenuates Photoreceptor Loss in the nclf Mouse Model of Neuronal Ceroid Lipofuscinosis

    PubMed Central

    Jankowiak, Wanda; Kruszewski, Katharina; Flachsbarth, Kai; Skevas, Christos; Richard, Gisbert; Rüther, Klaus; Braulke, Thomas; Bartsch, Udo

    2015-01-01

    A sustained intraocular administration of neurotrophic factors is among the strategies aimed at establishing treatments for currently untreatable degenerative retinal disorders. In the present study we have analyzed the neuroprotective effects of a continuous neural stem (NS) cell-based intraocular delivery of ciliary neurotrophic factor (CNTF) on photoreceptor cells in the nclf mouse, an animal model of the neurodegenerative lysosomal storage disorder variant late infantile neuronal ceroid lipofuscinosis (vLINCL). To this aim, we genetically modified adherently cultivated NS cells with a polycistronic lentiviral vector encoding a secretable variant of CNTF together with a Venus reporter gene (CNTF-NS cells). NS cells for control experiments (control-NS cells) were modified with a vector encoding the reporter gene tdTomato. Clonal CNTF-NS and control-NS cell lines were established using fluorescent activated cell sorting and intravitreally grafted into 14 days old nclf mice at the onset of retinal degeneration. The grafted cells preferentially differentiated into astrocytes that were attached to the posterior side of the lenses and the vitreal side of the retinas and stably expressed the transgenes for at least six weeks, the latest post-transplantation time point analyzed. Integration of donor cells into host retinas, ongoing proliferation of grafted cells or adverse effects of the donor cells on the morphology of the host eyes were not observed. Quantitative analyses of host retinas two, four and six weeks after cell transplantation revealed the presence of significantly more photoreceptor cells in eyes with grafted CNTF-NS cells than in eyes with grafted control-NS cells. This is the first demonstration that a continuous intraocular administration of a neurotrophic factor attenuates retinal degeneration in an animal model of neuronal ceroid lipofuscinosis. PMID:25992714

  9. Interaction of ganglioside GD3 with an EGF receptor sustains the self-renewal ability of mouse neural stem cells in vitro

    PubMed Central

    Wang, Jing; Yu, Robert K.

    2013-01-01

    Mounting evidence supports the notion that gangliosides serve regulatory roles in neurogenesis; little is known, however, about how these glycosphingolipids function in neural stem cell (NSC) fate determination. We previously demonstrated that ganglioside GD3 is a major species in embryonic mouse brain: more than 80% of the NSCs obtained by the neurosphere method express GD3. To investigate the functional role of GD3 in neurogenesis, we compared the properties of NSCs from GD3-synthase knockout (GD3S-KO) mice with those from their wild-type littermates. NSCs from GD3S-KO mice showed decreased self-renewal ability compared with those from the wild-type animals, and that decreased ability was accompanied by reduced expression of EGF receptor (EGFR) and an increased degradation rate of EGFR and EGF-induced ERK signaling. We also showed that EGFR switched from the low-density lipid raft fractions in wild-type NSCs to the high-density layers in the GD3S-KO NSCs. Immunochemical staining revealed colocalization of EGFR and GD3, and EGFR could be immunoprecipitated from the NSC lysate with an anti-GD3 antibody from the wild-type, but not from the GD3S-KO, mice. Tracking the localization of endocytosed EGFR with endocytosis pathway markers indicated that more EGFR in GD3S-KO NSCs translocated through the endosomal−lysosomal degradative pathway, rather than through the recycling pathway. Those findings support the idea that GD3 interacts with EGFR in the NSCs and that the interaction is responsible for sustaining the expression of EGFR and its downstream signaling to maintain the self-renewal capability of NSCs. PMID:24198336

  10. 15-Deoxy-delta 12,14-prostaglandin J2 biphasically regulates the proliferation of mouse hippocampal neural progenitor cells by modulating the redox state.

    PubMed

    Katura, Takashi; Moriya, Takahiro; Nakahata, Norimichi

    2010-04-01

    The activity of neural progenitor cells (NPCs) is regulated by various humoral factors. Although prostaglandin (PG) D(2) is known to mediate various physiological brain functions such as sleep, its actions on NPCs have not been fully understood. In the process of investigating the effects of PGD(2) on NPCs, we found that 15-deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)), an endogenous metabolite of PGD(2), exhibits a novel regulation of the proliferation of NPCs derived from mouse hippocampus. 15d-PGJ(2) showed biphasic effects on epidermal growth factor-induced proliferation of NPCs; facilitation at low concentrations ( approximately 0.3 muM) and suppression at higher concentrations (0.5-10 microM) in vitro. 2-Chloro-5-nitrobenzanilide (GW9662), an inhibitor of peroxisome proliferator-activated receptor gamma, known to be a molecular target for 15d-PGJ(2), failed to abolish the effects of 15d-PGJ(2). 9,10-dihydro-15d-PGJ(2) (CAY10410), a structural analog of 15d-PGJ(2) lacking the electrophilic carbon in the cyclopentenone ring, did not show 15d-PGJ(2)-like actions. Treatment with 15d-PGJ(2) increased the levels of reactive oxygen species and decreased endogenous GSH levels. Furthermore, supplementation with a membrane-permeable analog of glutathione, GSH ethyl ester (2 mM), diminished the biphasic effects of 15d-PGJ(2). Finally, cell division in the dentate gyrus of postnatal mice was increased by injection of low-dose (1 ng i.c.v.) 15d-PGJ(2) and suppressed by high-dose (30 ng) 15d-PGJ(2). These results suggest that 15d-PGJ(2) regulates the proliferation of NPCs via its electrophilic nature, which enables covalent binding to molecules such as GSH. PMID:20086036

  11. Molecular Clock Regulates Daily α1–2-Fucosylation of the Neural Cell Adhesion Molecule (NCAM) within Mouse Secondary Olfactory Neurons*

    PubMed Central

    Kondoh, Daisuke; Tateno, Hiroaki; Hirabayashi, Jun; Yasumoto, Yuki; Nakao, Reiko; Oishi, Katsutaka

    2014-01-01

    The circadian clock regulates various behavioral and physiological rhythms in mammals. Circadian changes in olfactory functions such as neuronal firing in the olfactory bulb (OB) and olfactory sensitivity have recently been identified, although the underlying molecular mechanisms remain unknown. We analyzed the temporal profiles of glycan structures in the mouse OB using a high-density microarray that includes 96 lectins, because glycoconjugates play important roles in the nervous system such as neurite outgrowth and synaptogenesis. Sixteen lectin signals significantly fluctuated in the OB, and the intensity of all three that had high affinity for α1–2-fucose (α1–2Fuc) glycan in the microarray was higher during the nighttime. Histochemical analysis revealed that α1–2Fuc glycan is located in a diurnal manner in the lateral olfactory tract that comprises axon bundles of secondary olfactory neurons. The amount of α1–2Fuc glycan associated with the major target glycoprotein neural cell adhesion molecule (NCAM) varied in a diurnal fashion, although the mRNA and protein expression of Ncam1 did not. The mRNA and protein expression of Fut1, a α1–2-specific fucosyltransferase gene, was diurnal in the OB. Daily fluctuation of the α1–2Fuc glycan was obviously damped in homozygous Clock mutant mice with disrupted diurnal Fut1 expression, suggesting that the molecular clock governs rhythmic α1–2-fucosylation in secondary olfactory neurons. These findings suggest the possibility that the molecular clock is involved in the diurnal regulation of olfaction via α1–2-fucosylation in the olfactory system. PMID:25384980

  12. Nuclear receptor TLX stimulates hippocampal neurogenesis and enhances learning and memory in a transgenic mouse model

    PubMed Central

    Murai, Kiyohito; Qu, Qiuhao; Sun, GuoQiang; Ye, Peng; Li, Wendong; Asuelime, Grace; Sun, Emily; Tsai, Guochuan E.; Shi, Yanhong

    2014-01-01

    The role of the nuclear receptor TLX in hippocampal neurogenesis and cognition has just begun to be explored. In this study, we generated a transgenic mouse model that expresses TLX under the control of the promoter of nestin, a neural precursor marker. Transgenic TLX expression led to mice with enlarged brains with an elongated hippocampal dentate gyrus and increased numbers of newborn neurons. Specific expression of TLX in adult hippocampal dentate gyrus via lentiviral transduction increased the numbers of BrdU+ cells and BrdU+NeuN+ neurons. Furthermore, the neural precursor-specific expression of the TLX transgene substantially rescued the neurogenic defects of TLX-null mice. Consistent with increased neurogenesis in the hippocampus, the TLX transgenic mice exhibited enhanced cognition with increased learning and memory. These results suggest a strong association between hippocampal neurogenesis and cognition, as well as significant contributions of TLX to hippocampal neurogenesis, learning, and memory. PMID:24927526

  13. Cardiac differentiation of mouse embryonic stem cells is influenced by a PPAR γ/PGC-1α-FNDC5 pathway during the stage of cardiac precursor cell formation.

    PubMed

    Zadegan, Faezeh Ghazvini; Ghaedi, Kamran; Kalantar, Seyed Mehdi; Peymani, Maryam; Hashemi, Motahare-Sadat; Baharvand, Hossein; Nasr-Esfahani, Mohammad Hossein

    2015-06-01

    Peroxisome proliferator-activated receptor (PPAR) γ co-activator 1α (PGC-1α) up-regulation induces FNDC5 expression in muscle and consequently causes browning of white adipose tissue (WAT). In addition to skeletal muscle, FNDC5 is mainly expressed in heart and brain tissues. Here, we demonstrate that FNDC5 expression increased during the process of cardiac differentiation of mouse embryonic stem cells (mESCs) similar to PGC-1α and PPARα. To testify the correlation between PGC-1α and FNDC5 in cardiac cell differentiation of mESCs, we utilized specific PPARγ agonist and antagonist in two stages of cardiac differentiation, during and post-cardiac precursor cells (CPCs) formation. Our results indicated that a reduction in PGC-1α expression, via treatment with GW9662 during CPCs formation stage, down-regulated FNDC5 transcript levels as well as mitochondrial markers which negatively influenced on the whole process of cardiac differentiation efficiency. On the other hand, increase PGC-1α expression during CPCs formation stage via rosiglitazone treatment increase FNDC5 and mitochondrial markers transcript levels which enhanced cardiac differentiation efficiency. Importantly, such alteration in PGC-1α expression at post-CPCs formation stage did not affect overall cardiac differentiation rate as expression of FNDC5 and mitochondrial markers were not significantly changed. We concluded that PPARγ agonist and antagonist induced up and down-regulation of PGC-1α and subsequently modulated the process of CPCs formation through an alteration in FNDC5 and mitochondrial markers expression. PMID:25936576

  14. A dynamic code of dorsal neural tube genes regulates the segregation between neurogenic and melanogenic neural crest cells

    PubMed Central

    Nitzan, Erez; Krispin, Shlomo; Pfaltzgraff, Elise R.; Klar, Avihu; Labosky, Patricia A.; Kalcheim, Chaya

    2013-01-01

    Understanding when and how multipotent progenitors segregate into diverse fates is a key question during embryonic development. The neural crest (NC) is an exemplary model system with which to investigate the dynamics of progenitor cell specification, as it generates a multitude of derivatives. Based on ‘in ovo’ lineage analysis, we previously suggested an early fate restriction of premigratory trunk NC to generate neural versus melanogenic fates, yet the timing of fate segregation and the underlying mechanisms remained unknown. Analysis of progenitors expressing a Foxd3 reporter reveals that prospective melanoblasts downregulate Foxd3 and have already segregated from neural lineages before emigration. When this downregulation is prevented, late-emigrating avian precursors fail to upregulate the melanogenic markers Mitf and MC/1 and the guidance receptor Ednrb2, generating instead glial cells that express P0 and Fabp. In this context, Foxd3 lies downstream of Snail2 and Sox9, constituting a minimal network upstream of Mitf and Ednrb2 to link melanogenic specification with migration. Consistent with the gain-of-function data in avians, loss of Foxd3 function in mouse NC results in ectopic melanogenesis in the dorsal tube and sensory ganglia. Altogether, Foxd3 is part of a dynamically expressed gene network that is necessary and sufficient to regulate fate decisions in premigratory NC. Their timely downregulation in the dorsal neural tube is thus necessary for the switch between neural and melanocytic phases of NC development. PMID:23615280

  15. The anti-inflammatory glycoprotein, CD200, restores neurogenesis and enhances amyloid phagocytosis in a mouse model of Alzheimer's disease.

    PubMed

    Varnum, Megan M; Kiyota, Tomomi; Ingraham, Kaitlin L; Ikezu, Seiko; Ikezu, Tsuneya

    2015-11-01

    Cluster of Differentiation-200 (CD200) is an anti-inflammatory glycoprotein expressed in neurons, T cells, and B cells, and its receptor is expressed on glia. Both Alzheimer's disease patients and mouse models display age-related or amyloid-β peptide (Aβ)-induced reductions in CD200. The goal of this study was to determine if neuronal CD200 expression restores hippocampal neurogenesis and reduces Aβ in the amyloid precursor protein mouse model. Amyloid precursor protein and wild-type mice were injected at 6 months of age with an adeno-associated virus expressing CD200 into the hippocampus and sacrificed at 12 months. CD200 expression restored neural progenitor cell proliferation and differentiation in the subgranular and granular cell layers of the dentate gyrus and reduced diffuse but not thioflavin-S(+) plaques in the hippocampus. In vitro studies demonstrated that CD200-stimulated microglia increased neural differentiation of neural stem cells and enhanced axon elongation and dendrite number. CD200 also enhanced Aβ uptake by microglia. These data indicate that CD200 is capable of enhancing microglia-mediated Aβ clearance and neural differentiation and has potential as a therapeutic for Alzheimer's disease. PMID:26315370

  16. Elevated Nuclear and Cytoplasmic FTY720-Phosphate in Mouse Embryonic Fibroblasts Suggests the Potential for Multiple Mechanisms in FTY720-Induced Neural Tube Defects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    FTY720 (fingolimod) is an FDA-approved drug to treat relapsing remitting multiple sclerosis. FTY720 treatment in pregnant inbred LM/Bc mice results in approximately 60% of embryos having a neural tube defect (NTD). Sphingosine kinases (Sphk1, Sphk2) phosphorylate FTY720 in vivo to form the bioactive...

  17. [Evaluation of imaging biomarker by transgenic mouse models].

    PubMed

    Maeda, Jun; Higuchi, Makoto; Suhara, Tetsuya

    2009-04-01

    The invention of trangenic and gene knockout mice contributes to the understanding of various brain functions. With the previous-generation positron emission tomography (PET) camera it was impossible to visualize the mouse brain functions, while the newly developed small-animal PET camera with higher resolution is enough to visualize the mouse brain functions. In the present study, we investigated the visualization of functional brain images for a few transgenic mouse models using the small-animal PET. In neurodegenerative illnesses such as Alzheimer disease (AD), the relationship between etiopathology and main symptoms has been elucidated relatively well; therefore several transgenic mice have been already developed. We succeeded in visualizing amyloid images in human mutant amyloid precursor protein (APP) transgenic mice brains. This result suggested that small-animal PET enabled the quantitative analysis of pathologies in the Tg mouse brain. Psychiatric disorders are presumed to have underlying multiple neural dysfunctions. Despite some efficient medicinal therapies having been already established, the etiopathology of mental illness and its biological markers have not been clarified. Thus, we investigated in type II Ca-calmodulin-dependent protein kinase alpha (CaMKII alpha) heterozygous knockout (hKO) mouse, a major protein kinase in the brain. The CaMKII alpha hKO mice have several abnormal behavioral phenotypes, such as hyper aggression and lack of anxiogenic responses; therefore CaMKII alpha might involve in the pathogenesis of mood disorder and affect personal characterizations. Furthermore, serotonin (5-HT) 1A receptor density in the CaMKII alpha hKO mouse brain changed among various brain regions compared to wild mice. These mechanistic insights, PET assays of Tg mice that we have established here, provide an efficient methodology for preclinical evaluation of emerging diagnostic and therapeutic agents for neurodegenerative and psychiatric illnesses

  18. Spontaneous CNV in a Novel Mutant Mouse Is Associated With Early VEGF-A–Driven Angiogenesis and Late-Stage Focal Edema, Neural Cell Loss, and Dysfunction

    PubMed Central

    Nagai, Norihiro; Lundh von Leithner, Pete; Izumi-Nagai, Kanako; Hosking, Brett; Chang, Bo; Hurd, Ron; Adamson, Peter; Adamis, Anthony P.; Foxton, Richard H.; Ng, Yin Shan; Shima, David T.

    2014-01-01

    Purpose. Characterization of a mouse model of spontaneous choroidal neovascularization (sCNV) and its effect on retinal architecture and function. Methods. The sCNV mouse phenotype was characterized by using fundus photography, fluorescein angiography, confocal scanning laser ophthalmoscopy (SLO), optical coherence tomography (OCT), ERG, immunostaining, biochemistry, and electron microscopy. A role for VEGF-A signaling in sCNV was investigated by using neutralizing antibodies and a role for macrophages explored by cell-depletion studies. Results. The sCNV starts between postnatal day 10 and 15 (P10–P15), increasing in number and severity causing RPE disruption and dysfunction. Various morphological methods confirmed the choroidal origin and subretinal position of the angiogenic vessels. At approximately P25, vessels were present in the outer retina with instances of anastomosis of some sCNV lesions with the retinal vasculature. The number of CNV lesions was significantly decreased by systemic blockade of the VEGF-A pathway. Choroidal neovascularization size also was significantly modulated by reducing the number of lesion-associated macrophages. Later stages of sCNV were associated with edema, neuronal loss, and dysfunction. Conclusions. The sCNV mouse is a new model for the study of both early and late events associated with choroidal neovascularization. Pharmacological reduction in sCNV with VEGF-A antagonists and an anti-inflammatory strategy suggests the model may be useful for investigating novel targets for treating human ocular neovascular disease. PMID:24845632

  19. Celsr1, a neural-specific gene encoding an unusual seven-pass transmembrane receptor, maps to mouse chromosome 15 and human chromosome 22qter.

    PubMed

    Hadjantonakis, A K; Sheward, W J; Harmar, A J; de Galan, L; Hoovers, J M; Little, P F

    1997-10-01

    We have identified Celsr1, a gene that encodes a developmentally regulated vertebrate seven-pass transmembrane protein. The extracellular domain of Celsr1 contains two regions each with homology to distinct classes of well-characterized motifs found in the extra-cellular domains of many cell surface molecules. The most N-terminal region contains a block of contiguous cadherin repeats, and C-terminal to this is a region containing seven epidermal growth factor-like repeats interrupted by two laminin A G-type repeats. Celsr1 is unique in that it contains this combination of repeats coupled to a seven-pass transmembrane domain. As part of the characterization of the Celsr1 gene, we have determined its chromosomal map location in both mouse and human. The European Collaborative Interspecific Backcross (EUCIB) and BXD recombinant inbred strains were used for mapping Celsr1 cDNA clones in the mouse, and fluorescence in situ hybridization was used to map human Celsr1 cosmid clones on metaphase chromosomes. We report that Celsr1 maps to proximal mouse Chromosome 15 and human chromosome 22qter, a region of conserved synteny. Reverse transcriptase-polymerase chain reaction analysis and in situ hybridization were used to determine the spatial restriction of Celsr1 transcripts in adult and embryonic mice. The results presented here extend our previous finding of expression of the Celsr1 receptor in the embryo and show that expression continues into adult life when expression in the brain is localized principally in the ependymal cell layer, choroid plexus, and the area postrema. PMID:9339365

  20. Examining the Neural and Astroglial Protective Effects of Cellular Prion Protein Expression and Cell Death Protease Inhibition in Mouse Cerebrocortical Mixed Cultures.

    PubMed

    Wang, Kevin K W; Yang, Zhihui; Chiu, Allen; Lin, Fan; Rubenstein, Richard

    2016-09-01

    Overexpression of cellular prion protein, PrP(C), has cytoprotective effects against neuronal injuries. Inhibition of cell death-associated proteases such as necrosis-linked calpain and apoptosis-linked caspase are also neuroprotective. Here, we systematically studied how PrP(C) expression levels and cell death protease inhibition affect cytotoxic challenges to both neuronal and glial cells in mouse cerebrocortical mixed cultures (CCM). Primary CCM derived from three mouse lines expressing no (PrP(C) knockout mice (PrPKO)), normal (wild-type (wt)), or high (tga20) levels of PrP(C) were subjected to necrotic challenge (calcium ionophore A23187) and apoptotic challenge (staurosporine (STS)). CCM which originated from tga20 mice provided the most robust neuron-astroglia protective effects against necrotic and early apoptotic cell death (lactate dehydrogenase (LDH) release) at 6 h but subsequently lost its cytoprotective effects. In contrast, PrPKO-derived cultures displayed elevated A23187- and STS-induced cell death at 24 h. Calpain inhibitor SNJ-1945 protected against A23187 challenge at 6 h in CCM from all three mouse lines but protected only against A23187 and STS treatments by 24 h in the PrPKO line. In parallel, caspase inhibitor Z-D-DCB protected against pro-apoptotic STS challenge at 6 and 24 h. Furthermore, we also examined αII-spectrin breakdown products (primarily from neurons) and glial fibrillary acidic protein (GFAP) breakdown products (from astroglia) as cytoskeletal proteolytic biomarkers. Overall, it appeared that both neurons and astroglial cells were less vulnerable to proteolytic attack during A23187 and STS challenges in tga20-derived cultures but more vulnerable in PrPKO-derived cultures. In addition, calpain and caspase inhibitors provide further protection against respective protease attacks on these neuronal and glial cytoskeletal proteins in CCM regardless of mouse-line origin. Lastly, some synergistic cytoprotective effects between Pr

  1. Mutations in PTF1A are not a common cause for human VATER/VACTERL association or neural tube defects mirroring Danforth's short tail mouse.

    PubMed

    Gurung, Nirmala; Grosse, Greta; Draaken, Markus; Hilger, Alina C; Nauman, Nuzhat; Müller, Andreas; Gembruch, Ulrich; Merz, Waltraut M; Reutter, Heiko; Ludwig, Michael

    2015-07-01

    Danforth's short tail (Sd) mutant mice exhibit defects of the neural tube and other abnormalities, which are similar to the human vertebral anomalies, anal atresia, cardiac defects, tracheosophageal fistula and/or esophageal atresia, renal and radial abnormalities, and limb defects (VATER/VACTERL) association, including defects of the hindgut. Sd has been shown to underlie ectopic gene expression of murine Ptf1a, which encodes pancreas-specific transcription factor 1A, due to the insertion of a retrotansposon in its 5' regulatory domain. In order to investigate the possible involvement of this gene in human VATER/VACTERL association and human neural tube defects (NTDs), a sequence analysis was performed. DNA samples from 103 patients with VATER/VACTERL and VATER/VACTERL‑like association, all presenting with anorectal malformations, and 72 fetuses with NTDs, where termination of pregnancy had been performed, were included in the current study. The complete PTF1A coding region, splice sites and 1.5 kb of the 5' flanking promotor region was sequenced. However, no pathogenic alterations were detected. The results of the present study do not support the hypothesis that high penetrant mutations in these regions of PTF1A are involved in the development of human VATER/VACTERL association or NTDs, although rare mutations may be detectable in larger patient samples. PMID:25775927

  2. Nitric Oxide Signaling and Neural Stem Cell Differentiation in Peripheral Nerve Regeneration

    PubMed Central

    Tao Li, Jessica; Somasundaram, Chandra; Bian, Ka; Xiong, Weijun; Mahmooduddin, Faiz; Nath, Rahul K.; Murad, Ferid

    2010-01-01

    Objective: The objective was to examine whether nitric oxide signaling plays a role in human embryonic stem cell differentiation into neural cells. This article reviews current literature on nitric oxide signaling and neural stem cell differentiation for potential therapeutic application to peripheral nerve regeneration. Methods: Human embryonic H9-stem cells were grown, maintained on mitomycin C–treated mouse embryonic fibroblast feeder layer, cultured on Matrigel to be feeder-free, and used for all the experiments. Fluorescent dual-immunolabeling and confocal image analysis were used to detect the presence of the neural precursor cell markers nestin and nitric oxide synthase-1. Fluorescence-activated cell sorting analysis was used to determine the percentage of expression. Results: We have shown the confocal image of stage 1 human embryonic stem cells coexpressing nestin and nitric oxide synthase-1. Fluorescence-activated cell sorting analysis indicated 24.3% positive labeling of nitric oxide synthase-1. Adding retinoic acid (10−6 M) to the culture medium increased the percent of nitric oxide synthase-1 positive cells to 33.9%. Combining retinoic acid (10−6 M) with 8-brom cyclic guanosine monophosphate (10−5 M), the fluorescence-activated cell sorting analysis demonstrated a further increase of nitric oxide synthase-1 positive cells to 45.4%. Our current results demonstrate a prodifferentiation potency of nitric oxide synthase-1, stimulated by retinoic acid with and without cyclic guanosine monophosphate. Conclusion: We demonstrated for the first time how nitric oxide/cyclic guanosine monophosphate signaling contributes to the development of neural precursors derived from human embryonic stem cells and enhances the differentiation of precursors toward functional neurons for peripheral nerve regeneration. PMID:20563304

  3. Neurotoxic effects of ochratoxin A on the subventricular zone of adult mouse brain.

    PubMed

    Paradells, Sara; Rocamonde, Brenda; Llinares, Cristina; Herranz-Pérez, Vicente; Jimenez, Misericordia; Garcia-Verdugo, Jose Manuel; Zipancic, Ivan; Soria, Jose Miguel; Garcia-Esparza, Ma Angeles

    2015-07-01

    Ochratoxin A (OTA), a mycotoxin that was discovered as a secondary metabolite of the fungal species Aspergillus and Penicillium, is a common contaminant in food and animal feed. This mycotoxin has been described as teratogenic, carcinogenic, genotoxic, immunotoxic and has been proven a potent neurotoxin. Other authors have previously reported the effects of OTA in different structures of the central nervous system as well as in some neurogenic regions. However, the impact of OTA exposure in the subventricular zone (SVZ) has not been assessed yet. To elucidate whether OTA affects neural precursors of the mouse SVZ we investigated, in vitro and in vivo, the effects of OTA exposure on the SVZ and on the neural precursors obtained from this neurogenic niche. In this work, we prove the cumulative effect of OTA exposure on proliferation, differentiation and depletion of neural stem cells cultured from the SVZ. In addition, we corroborated these results in vivo by immunohistochemistry and electron microscopy. As a result, we found a significant alteration in the proliferation process, which was evidenced by a decrease in the number of 5-bromo-2-deoxyuridine-positive cells and glial cells, as well as, a significant decrease in the number of neuroblasts in the SVZ. To summarize, in this study we demonstrate how OTA could be a threat to the developing and the adult SVZ through its impact in cell viability, proliferation and differentiation in a dose-dependent manner. PMID:25256750

  4. Polyimide Precursor Solid Residuum

    NASA Technical Reports Server (NTRS)

    Weiser, Erik S. (Inventor); St.Clair, Terry L. (Inventor); Echigo, Yoshiaki (Inventor); Kaneshiro, Hisayasu (Inventor)

    2001-01-01

    A polyimide precursor solid residuum is an admixture of an aromatic dianhydride or derivative thereof and an aromatic diamine or derivative thereof plus a complexing agent, which is complexed with the admixture by hydrogen bonding. The polyimide precursor solid residuum is effectively employed in the preparation of polyimide foam and the fabrication of polyimide foam structures.

  5. Nonhuman sialic acid Neu5Gc is very low in human embryonic stem cell-derived neural precursors differentiated with B27/N2 and noggin: implications for transplantation.

    PubMed

    Nasonkin, Igor O; Koliatsos, Vassilis E

    2006-10-01

    A concern recently has been raised that human embryonic stem cell (HESC) lines cultured with currently available methods may have limited clinical usefulness due to the immunogenicity of the nonhuman sialic acid Neu5Gc incorporated into their membranes during culturing. We find this concern has little relevance to neural differentiation protocols with B27/N2/noggin because of the gradual decline of Neu5Gc to less than 1% in differentiating cells upon switching to B27/N2 medium. PMID:16806174

  6. Neural Stem Cell-based Cell Carriers Enhance Therapeutic Efficacy of an Oncolytic Adenovirus in an Orthotopic Mouse Model of Human Glioblastoma

    PubMed Central

    Ahmed, Atique U; Thaci, Bart; Alexiades, Nikita G; Han, Yu; Qian, Shuo; Liu, Feifei; Balyasnikova, Irina V; Ulasov, Ilya Y; Aboody, Karen S; Lesniak, Maciej S

    2011-01-01

    The potential utility of oncolytic adenoviruses as anticancer agents is significantly hampered by the inability of the currently available viral vectors to effectively target micrometastatic tumor burden. Neural stem cells (NSCs) have the ability to function as cell carriers for targeted delivery of an oncolytic adenovirus because of their inherent tumor-tropic migratory ability. We have previously reported that in vivo delivery of CRAd-S-pk7, a glioma-restricted oncolytic adenovirus, can enhance the survival of animals with experimental glioma. In this study, we show that intratumoral delivery of NSCs loaded with the CRAD-S-pk7 in an orthotopic xenograft model of human glioma is able to not only inhibit tumor growth but more importantly to increase median survival by ~50% versus animals treated with CRAd-S-pk7 alone (P = 0.0007). We also report that oncolytic virus infection upregulates different chemoattractant receptors and significantly enhances migratory capacity of NSCs both in vitro and in vivo. Our data further suggest that NSC-based carriers have the potential to improve the clinical efficacy of antiglioma virotherapy by not only protecting therapeutic virus from the host immune system, but also amplifying the therapeutic payload selectively at tumor sites. PMID:21629227

  7. Neural stem cell-based cell carriers enhance therapeutic efficacy of an oncolytic adenovirus in an orthotopic mouse model of human glioblastoma.

    PubMed

    Ahmed, Atique U; Thaci, Bart; Alexiades, Nikita G; Han, Yu; Qian, Shuo; Liu, Feifei; Balyasnikova, Irina V; Ulasov, Ilya Y; Aboody, Karen S; Lesniak, Maciej S

    2011-09-01

    The potential utility of oncolytic adenoviruses as anticancer agents is significantly hampered by the inability of the currently available viral vectors to effectively target micrometastatic tumor burden. Neural stem cells (NSCs) have the ability to function as cell carriers for targeted delivery of an oncolytic adenovirus because of their inherent tumor-tropic migratory ability. We have previously reported that in vivo delivery of CRAd-S-pk7, a glioma-restricted oncolytic adenovirus, can enhance the survival of animals with experimental glioma. In this study, we show that intratumoral delivery of NSCs loaded with the CRAD-S-pk7 in an orthotopic xenograft model of human glioma is able to not only inhibit tumor growth but more importantly to increase median survival by ~50% versus animals treated with CRAd-S-pk7 alone (P = 0.0007). We also report that oncolytic virus infection upregulates different chemoattractant receptors and significantly enhances migratory capacity of NSCs both in vitro and in vivo. Our data further suggest that NSC-based carriers have the potential to improve the clinical efficacy of antiglioma virotherapy by not only protecting therapeutic virus from the host immune system, but also amplifying the therapeutic payload selectively at tumor sites. PMID:21629227

  8. Cell Sorting of Neural Stem and Progenitor Cells from the Adult Mouse Subventricular Zone and Live-imaging of their Cell Cycle Dynamics.

    PubMed

    Daynac, Mathieu; Morizur, Lise; Kortulewski, Thierry; Gauthier, Laurent R; Ruat, Martial; Mouthon, Marc-André; Boussin, François D

    2015-01-01

    Neural stem cells (NSCs) in the subventricular zone of the lateral ventricles (SVZ) sustain olfactory neurogenesis throughout life in the mammalian brain. They successively generate transit amplifying cells (TACs) and neuroblasts that differentiate into neurons once they integrate the olfactory bulbs. Emerging fluorescent activated cell sorting (FACS) techniques have allowed the isolation of NSCs as well as their progeny and have started to shed light on gene regulatory networks in adult neurogenic niches. We report here a cell sorting technique that allows to follow and distinguish the cell cycle dynamics of the above-mentioned cell populations from the adult SVZ with a LeX/EGFR/CD24 triple staining. Isolated cells are then plated as adherent cells to explore in details their cell cycle progression by time-lapse video microscopy. To this end, we use transgenic Fluorescence Ubiquitination Cell Cycle Indicator (FUCCI) mice in which cells are red-fluorescent during G1 phase due to a G1 specific red-Cdt1 reporter. This method has recently revealed that proliferating NSCs progressively lengthen their G1 phase during aging, leading to neurogenesis impairment. This method is easily transposable to other systems and could be of great interest for the study of the cell cycle dynamics of brain cells in the context of brain pathologies. PMID:26436641

  9. Sympathetic neural signaling via the β2-adrenergic receptor suppresses T-cell receptor-mediated human and mouse CD8(+) T-cell effector function.

    PubMed

    Estrada, Leonardo D; Ağaç, Didem; Farrar, J David

    2016-08-01

    Postganglionic sympathetic neurons innervate secondary lymphoid organs and secrete norepinephrine (NE) as the primary neurotransmitter. NE binds and signals through five distinct members of the adrenergic receptor family. In this study, we show elevated expression of the β2-adrenergic receptor (ADRB2) on primary human CD8(+) effector memory T cells. Treatment of both human and murine CD8(+) T cells with NE decreased IFN-γ and TNF-α secretion and suppressed their cytolytic capacity in response to T-cell receptor (TCR) activation. The effects of NE were specifically reversed by β2-specific antagonists. Adrb2(-/-) CD8(+) T cells were completely resistant to the effects of NE. Further, the ADRB2-specific pharmacological ligand, albuterol, significantly suppressed effector functions in both human and mouse CD8(+) T cells. While both TCR activation and stimulation with IL-12 + IL-18 were able to induce inflammatory cytokine secretion, NE failed to suppress IFN-γ secretion in response to IL-12 + IL18. Finally, the long-acting ADRB2-specific agonist, salmeterol, markedly reduced the cytokine secretion capacity of CD8(+) T cells in response to infection with vesicular stomatitis virus. This study reveals a novel intrinsic role for ADRB2 signaling in CD8(+) T-cell function and underscores the novel role this pathway plays in adaptive T-cell responses to infection. PMID:27222010

  10. Earthquakes: hydrogeochemical precursors

    USGS Publications Warehouse

    Ingebritsen, Steven E.; Manga, Michael

    2014-01-01

    Earthquake prediction is a long-sought goal. Changes in groundwater chemistry before earthquakes in Iceland highlight a potential hydrogeochemical precursor, but such signals must be evaluated in the context of long-term, multiparametric data sets.

  11. Shifts in the Vascular endothelial growth factor (Vegf) isoforms result in transcriptome changes correlated with early neural stem cell proliferation and differentiation in mouse forebrain

    PubMed Central

    Cain, Jacob T.; Berosik, Matthew A.; Snyder, Stephanie D.; Crawford, Natalie F.; Nour, Shirin I.; Schaubhut, Geoffrey J.; Darland, Diane C.

    2014-01-01

    Regulation of neural stem cell (NSC) fate decisions is critical during the transition from a multicellular mammalian forebrain neuroepithelium to the multi-layered neocortex. Forebrain development requires coordinated vascular investment alongside NSC differentiation. Vascular endothelial growth factor A (Vegf) has proven to be a pleiotrophic gene whose multiple protein isoforms regulate a broad range of effects in neurovascular systems. To test the hypothesis that the Vegf isoforms (120, 164, and 188) are required for normal forebrain development, we analyzed the forebrain transcriptome of mice expressing specific Vegf isoforms, Vegf120, VegfF188, or a combination of Vegf120/188. Transcriptome analysis identified differentially expressed genes in embryonic day (E) 9.5 forebrain, a time point preceding dramatic neuroepithelial expansion and vascular investment in the telencephalon. Meta-analysis identified gene pathways linked to chromosome-level modifications, cell fate regulation, and neurogenesis that were altered in Vegf isoform mice. Based on these gene network shifts, we predicted that NSC populations would be affected in later stages of forebrain development. In the E11.5 telencephalon, we quantified mitotic cells [Phospho-Histone H3 (pHH3)-positive] and intermediate progenitor cells (Tbr2/Eomes-positive), observing quantitative and qualitative shifts in these populations. We observed qualitative shifts in cortical layering at P0, particularly with Ctip2-positive cells in layer V. The results identify a suite of genes and functional gene networks that can be used to further dissect the role of Vegf in regulating NSC differentiation and downstream consequences for NSC fate decisions. PMID:24124161

  12. Conditional deletion of AP-2β in mouse cranial neural crest results in anterior segment dysgenesis and early-onset glaucoma.

    PubMed

    Martino, Vanessa B; Sabljic, Thomas; Deschamps, Paula; Green, Rebecca M; Akula, Monica; Peacock, Erica; Ball, Alexander; Williams, Trevor; West-Mays, Judith A

    2016-08-01

    Anterior segment dysgenesis (ASD) encompasses a group of developmental disorders in which a closed angle phenotype in the anterior chamber of the eye can occur and 50% of patients develop glaucoma. Many ASDs are thought to involve an inappropriate patterning and migration of the periocular mesenchyme (POM), which is derived from cranial neural crest cells (NCCs) and mesoderm. Although, the mechanism of this disruption is not well understood, a number of transcriptional regulatory molecules have previously been implicated in ASDs. Here, we investigate the function of the transcription factor AP-2β, encoded by Tfap2b, which is expressed in NCCs and their derivatives. Wnt1-Cre-mediated conditional deletion of Tfap2b in NCCs resulted in post-natal ocular defects typified by opacity. Histological data revealed that the conditional AP-2β NCC knockout (KO) mutants exhibited dysgenesis of multiple structures in the anterior segment of the eye including defects in the corneal endothelium, corneal stroma, ciliary body and disruption in the iridocorneal angle with adherence of the iris to the cornea. We further show that this phenotype leads to a significant increase in intraocular pressure and a subsequent loss of retinal ganglion cells and optic nerve degeneration, features indicative of glaucoma. Overall, our findings demonstrate that AP-2β is required in the POM for normal development of the anterior segment of the eye and that the AP-2β NCC KO mice might serve as a new and exciting model of ASD and glaucoma that is fully penetrant and with early post-natal onset. PMID:27483349

  13. Conditional deletion of AP-2β in mouse cranial neural crest results in anterior segment dysgenesis and early-onset glaucoma

    PubMed Central

    Martino, Vanessa B.; Sabljic, Thomas; Deschamps, Paula; Green, Rebecca M.; Akula, Monica; Peacock, Erica; Ball, Alexander

    2016-01-01

    ABSTRACT Anterior segment dysgenesis (ASD) encompasses a group of developmental disorders in which a closed angle phenotype in the anterior chamber of the eye can occur and 50% of patients develop glaucoma. Many ASDs are thought to involve an inappropriate patterning and migration of the periocular mesenchyme (POM), which is derived from cranial neural crest cells (NCCs) and mesoderm. Although, the mechanism of this disruption is not well understood, a number of transcriptional regulatory molecules have previously been implicated in ASDs. Here, we investigate the function of the transcription factor AP-2β, encoded by Tfap2b, which is expressed in NCCs and their derivatives. Wnt1-Cre-mediated conditional deletion of Tfap2b in NCCs resulted in post-natal ocular defects typified by opacity. Histological data revealed that the conditional AP-2β NCC knockout (KO) mutants exhibited dysgenesis of multiple structures in the anterior segment of the eye including defects in the corneal endothelium, corneal stroma, ciliary body and disruption in the iridocorneal angle with adherence of the iris to the cornea. We further show that this phenotype leads to a significant increase in intraocular pressure and a subsequent loss of retinal ganglion cells and optic nerve degeneration, features indicative of glaucoma. Overall, our findings demonstrate that AP-2β is required in the POM for normal development of the anterior segment of the eye and that the AP-2β NCC KO mice might serve as a new and exciting model of ASD and glaucoma that is fully penetrant and with early post-natal onset. PMID:27483349

  14. Targeting p38 mitogen-activated protein kinase signaling restores subventricular zone neural stem cells and corrects neuromotor deficits in Atm knockout mouse.

    PubMed

    Kim, Jeesun; Wong, Paul K Y

    2012-07-01

    Ataxia-telangiectasia (A-T) is a progressive degenerative disorder that results in major neurological disability. In A-T patients, necropsy has revealed atrophy of cerebellar cortical layers along with Purkinje and granular cell loss. We have previously identified an oxidative stress-mediated increase in phospho-p38 mitogen-activated protein kinase (MAPK) and the resultant downregulation of Bmi-1 and upregulation of p21 as key components of the mechanism causing defective proliferation of neural stem cells (NSCs) isolated from the subventricular zone (SVZ) of Atm(-/-) mice. However, the in vivo aspect of alteration in SVZ tissue and the functional significance of p38MAPK activation in NSCs for neuropathogenesis of ATM deficiency remain unknown. Here we show that the NSC population was abnormally decreased in the SVZ of 3-month-old Atm(-/-) mice; this decrease was accompanied by p38MAPK activation. However, after a 2-month treatment with the p38MAPK inhibitor SB203580, starting at 1 month old, Atm(-/-) mice showed restoration of normal levels of Bmi-1 and p21 with the rescue of NSC population in the SVZ. In addition, treated Atm(-/-) mice exhibited more Purkinje cells in the cerebellum. Most importantly, motor coordination of Atm(-/-) mice was significantly improved in the treatment group. Our results show for the first time in vivo evidence of depleted NSCs in the SVZ of Atm(-/-) mice and also demonstrate that pharmacologic inhibition of p38MAPK signaling has the potential to treat neurological defects of A-T. This study provides a promising approach targeting the oxidative stress-dependent p38 signaling pathway not only for A-T but also for other neurodegenerative disorders. PMID:23197859

  15. Stochastic cellular automata model of neural networks.

    PubMed

    Goltsev, A V; de Abreu, F V; Dorogovtsev, S N; Mendes, J F F

    2010-06-01

    We propose a stochastic dynamical model of noisy neural networks with complex architectures and discuss activation of neural networks by a stimulus, pacemakers, and spontaneous activity. This model has a complex phase diagram with self-organized active neural states, hybrid phase transitions, and a rich array of behaviors. We show that if spontaneous activity (noise) reaches a threshold level then global neural oscillations emerge. Stochastic resonance is a precursor of this dynamical phase transition. These oscillations are an intrinsic property of even small groups of 50 neurons. PMID:20866454

  16. Application of a fuzzy neural network model in predicting polycyclic aromatic hydrocarbon-mediated perturbations of the Cyp1b1 transcriptional regulatory network in mouse skin

    SciTech Connect

    Larkin, Andrew; Siddens, Lisbeth K.; Krueger, Sharon K.; Tilton, Susan C.; Waters, Katrina M.; Williams, David E.; Baird, William M.

    2013-03-01

    Polycyclic aromatic hydrocarbons (PAHs) are present in the environment as complex mixtures with components that have diverse carcinogenic potencies and mostly unknown interactive effects. Non-additive PAH interactions have been observed in regulation of cytochrome P450 (CYP) gene expression in the CYP1 family. To better understand and predict biological effects of complex mixtures, such as environmental PAHs, an 11 gene input-1 gene output fuzzy neural network (FNN) was developed for predicting PAH-mediated perturbations of dermal Cyp1b1 transcription in mice. Input values were generalized using fuzzy logic into low, medium, and high fuzzy subsets, and sorted using k-means clustering to create Mamdani logic functions for predicting Cyp1b1 mRNA expression. Model testing was performed with data from microarray analysis of skin samples from FVB/N mice treated with toluene (vehicle control), dibenzo[def,p]chrysene (DBC), benzo[a]pyrene (BaP), or 1 of 3 combinations of diesel particulate extract (DPE), coal tar extract (CTE) and cigarette smoke condensate (CSC) using leave-one-out cross-validation. Predictions were within 1 log{sub 2} fold change unit of microarray data, with the exception of the DBC treatment group, where the unexpected down-regulation of Cyp1b1 expression was predicted but did not reach statistical significance on the microarrays. Adding CTE to DPE was predicted to increase Cyp1b1 expression, whereas adding CSC to CTE and DPE was predicted to have no effect, in agreement with microarray results. The aryl hydrocarbon receptor repressor (Ahrr) was determined to be the most significant input variable for model predictions using back-propagation and normalization of FNN weights. - Highlights: ► Tested a model to predict PAH mixture-mediated changes in Cyp1b1 expression ► Quantitative predictions in agreement with microarrays for Cyp1b1 induction ► Unexpected difference in expression between DBC and other treatments predicted ► Model predictions

  17. Neural induction and early patterning in vertebrates.

    PubMed

    Ozair, Mohammad Zeeshan; Kintner, Chris; Brivanlou, Ali H

    2013-07-01

    In vertebrates, the development of the nervous system is triggered by signals from a powerful 'organizing' region of the early embryo during gastrulation. This phenomenon--neural induction--was originally discovered and given conceptual definition by experimental embryologists working with amphibian embryos. Work on the molecular circuitry underlying neural induction, also in the same model system, demonstrated that elimination of ongoing transforming growth factor-β (TGFβ) signaling in the ectoderm is the hallmark of anterior neural-fate acquisition. This observation is the basis of the 'default' model of neural induction. Endogenous neural inducers are secreted proteins that act to inhibit TGFβ ligands in the dorsal ectoderm. In the ventral ectoderm, where the signaling ligands escape the inhibitors, a non-neural fate is induced. Inhibition of the TGFβ pathway has now been demonstrated to be sufficient to directly induce neural fate in mammalian embryos as well as pluripotent mouse and human embryonic stem cells. Hence the molecular process that delineates neural from non-neural ectoderm is conserved across a broad range of organisms in the evolutionary tree. The availability of embryonic stem cells from mouse, primates, and humans will facilitate further understanding of the role of signaling pathways and their downstream mediators in neural induction in vertebrate embryos. PMID:24014419

  18. Multimodal imaging of subventricular zone neural stem/progenitor cells in the cuprizone mouse model reveals increased neurogenic potential for the olfactory bulb pathway, but no contribution to remyelination of the corpus callosum.

    PubMed

    Guglielmetti, Caroline; Praet, Jelle; Rangarajan, Janaki Raman; Vreys, Ruth; De Vocht, Nathalie; Maes, Frederik; Verhoye, Marleen; Ponsaerts, Peter; Van der Linden, Annemie

    2014-02-01

    Multiple sclerosis is a devastating demyelinating disease of the central nervous system (CNS) in which endogenous remyelination, and thus recovery, often fails. Although the cuprizone mouse model allowed elucidation of many molecular factors governing remyelination, currently very little is known about the spatial origin of the oligodendrocyte progenitor cells that initiate remyelination in this model. Therefore, we here investigated in this model whether subventricular zone (SVZ) neural stem/progenitor cells (NSPCs) contribute to remyelination of the splenium following cuprizone-induced demyelination. Experimentally, from the day of in situ NSPC labeling, C57BL/6J mice were fed a 0.2% cuprizone diet during a 4-week period and then left to recover on a normal diet for 8weeks. Two in situ labeling strategies were employed: (i) NSPCs were labeled by intraventricular injection of micron-sized iron oxide particles and then followed up longitudinally by means of magnetic resonance imaging (MRI), and (ii) SVZ NSPCs were transduced with a lentiviral vector encoding the eGFP and Luciferase reporter proteins for longitudinal monitoring by means of in vivo bioluminescence imaging (BLI). In contrast to preceding suggestions, no migration of SVZ NSPC towards the demyelinated splenium was observed using both MRI and BLI, and further validated by histological analysis, thereby demonstrating that SVZ NSPCs are unable to contribute directly to remyelination of the splenium in the cuprizone model. Interestingly, using longitudinal BLI analysis and confirmed by histological analysis, an increased migration of SVZ NSPC-derived neuroblasts towards the olfactory bulb was observed following cuprizone treatment, indicative for a potential link between CNS inflammation and increased neurogenesis. PMID:23933305

  19. Bone-Marrow-Derived Mesenchymal Stem Cells Promote Proliferation and Neuronal Differentiation of Niemann–Pick Type C Mouse Neural Stem Cells by Upregulation and Secretion of CCL2

    PubMed Central

    Lee, Hyun; Kang, Ji Eun; Lee, Jong Kil; Bae, Jae-sung

    2013-01-01

    Abstract Niemann–Pick type C (NP-C) disease is a neurodegenerative disorder characterized neuropathologically by ballooned neurons distended with lipid storage and widespread neuronal loss. Neural stem cells (NSC) derived from NP-C disease models have decreased ability for self-renewal and neuronal differentiation. Investigation of neurogenesis in the adult brain has suggested that NP-C disease can be overcome, or at least ameliorated, by the generation of new neurons. Bone-marrow-derived mesenchymal stem cells (BM-MSCs) are regarded as potential candidates for use in the treatment of neurodegenerative disorders because of their ability to promote neurogenesis. The underlying mechanisms of BM-MSC-induced promotion of neurogenesis, however, have not been resolved. The aim of the present study was to examine the mechanism of neurogenesis by BM-MSCs in NP-C disease. Coculture of embryonic NSCs from NP-C mice that exhibit impaired ability for self-renewal and decreased rates of neuronal differentiation with BM-MSCs resulted in an enhanced capacity for self-renewal and an increased ability for differentiation into neurons or oligodendrocytes. In addition, results of in vivo studies have demonstrated that transplantation of intracerebral BM-MSCs resulted in stimulated proliferation and neuronal differentiation of NSCs within the subventricular zone. Of particular interest, enhanced proliferation and neuronal differentiation of endogenous NP-C mouse NSCs showed an association with elevated release of the chemokine (C-C motif) ligand 2 (CCL2) from BM-MSCs. These effects suggest that soluble CCL2 derived from BM-MSCs can modulate endogenous NP-C NSCs, resulting in their improved proliferation and neuronal differentiation in mice. PMID:23659480

  20. Dual-energy precursor and nuclear erythroid-related factor 2 activator treatment additively improve redox glutathione levels and neuron survival in aging and Alzheimer mouse neurons upstream of reactive oxygen species.

    PubMed

    Ghosh, Debolina; LeVault, Kelsey R; Brewer, Gregory J

    2014-01-01

    To determine whether glutathione (GSH) loss or increased reactive oxygen species (ROS) are more important to neuron loss, aging, and Alzheimer's disease (AD), we stressed or boosted GSH levels in neurons isolated from aging 3xTg-AD neurons compared with those from age-matched nontransgenic (non-Tg) neurons. Here, using titrating with buthionine sulfoximine, an inhibitor of γ-glutamyl cysteine synthetase (GCL), we observed that GSH depletion increased neuronal death of 3xTg-AD cultured neurons at increasing rates across the age span, whereas non-Tg neurons were resistant to GSH depletion until old age. Remarkably, the rate of neuron loss with ROS did not increase in old age and was the same for both genotypes, which indicates that cognitive deficits in the AD model were not caused by ROS. Therefore, we targeted for neuroprotection activation of the redox sensitive transcription factor, nuclear erythroid-related factor 2 (Nrf2) by 18 alpha glycyrrhetinic acid to stimulate GSH synthesis through GCL. This balanced stimulation of a number of redox enzymes restored the lower levels of Nrf2 and GCL seen in 3xTg-AD neurons compared with those of non-Tg neurons and promoted translocation of Nrf2 to the nucleus. By combining the Nrf2 activator together with the NADH precursor, nicotinamide, we increased neuron survival against amyloid beta stress in an additive manner. These stress tests and neuroprotective treatments suggest that the redox environment is more important for neuron survival than ROS. The dual neuroprotective treatment with nicotinamide and an Nrf2 inducer indicates that these age-related and AD-related changes are reversible. PMID:23954169

  1. Apoptosome inactivation rescues proneural and neural cells from neurodegeneration.

    PubMed

    Cozzolino, M; Ferraro, E; Ferri, A; Rigamonti, D; Quondamatteo, F; Ding, H; Xu, Z S; Ferrari, F; Angelini, D F; Rotilio, G; Cattaneo, E; Carrì, M T; Cecconi, F

    2004-11-01

    Deficiency of the apoptosome component Apaf1 leads to accumulation of supernumerary brain cells in mouse embryos. We observed that neural precursor cells (NPCs) in Apaf1(-/-) embryos escape programmed cell death, proliferate and retain their potential to differentiate. To evaluate the circumstances of Apaf1(-/-) NPC survival and investigate their fate under neurodegenerative conditions, we established cell lines of embryonic origin (ETNA). We found that Apaf1(-/-) NPCs resist common apoptotic stimuli and neurodegenerative inducers such as amyloid-beta peptide (typical of Alzheimer's disease) and mutant G93A superoxide dismutase 1 (typical of familial amyotrophic lateral sclerosis). Similar results were obtained in Apaf1(-/-) primary cells. When death is prevented by Apaf1 deficiency, cytochrome c is released from mitochondria and rapidly degraded by the proteasome, but mitochondria remain intact. Under these conditions, neither activation by cleavage of initiator caspases nor release of alternative apoptotic inducers from mitochondria takes place. In addition, NPCs can still differentiate, as revealed by neurite outgrowth and expression of differentiation markers. Our findings imply that the mitochondrion/apoptosome pathway is the main route of proneural and neural cells to death and that its inhibition prevents them from dismantling in neurodegenerative conditions. Indeed, the ETNA cell model is ideally suited for exploring the potential of novel cell therapies for the treatment of human neurodegenerations. PMID:15257302

  2. NKCC1-Deficiency Results in Abnormal Proliferation of Neural Progenitor Cells of the Lateral Ganglionic Eminence.

    PubMed

    Magalhães, Ana Cathia; Rivera, Claudio

    2016-01-01

    The proliferative pool of neural progenitor cells is maintained by exquisitely controlled mechanisms for cell cycle regulation. The Na-K-Cl cotransporter (NKCC1) is important for regulating cell volume and the proliferation of different cell types in vitro. NKCC1 is expressed in ventral telencephalon of embryonic brains suggesting a potential role in neural development of this region. The ventral telencephalon is a major source for both interneuron and oligodendrocyte precursor cells. Whether NKCC1 is involved in the proliferation of these cell populations remains unknown. In order to assess this question, we monitored several markers for neural, neuronal, and proliferating cells in wild-type (WT) and NKCC1 knockout (KO) mouse brains. We found that NKCC1 was expressed in neural progenitor cells from the lateral ganglionic eminence (LGE) at E12.5. Mice lacking NKCC1 expression displayed reduced phospho-Histone H3 (PH3)-labeled mitotic cells in the ventricular zone (VZ) and reduced cell cycle reentry. Accordingly, we found a significant reduction of Sp8-labeled immature interneurons migrating from the dorsal LGE in NKCC1-deficient mice at a later developmental stage. Interestingly, at E14.5, NKCC1 regulated also the formation of Olig2-labeled oligodendrocyte precursor cells. Collectively, these findings show that NKCC1 serves in vivo as a modulator of the cell cycle decision in the developing ventral telencephalon at the early stage of neurogenesis. These results present a novel mechanistic avenue to be considered in the recent proposed involvement of chloride transporters in a number of developmentally related diseases, such as epilepsy, autism, and schizophrenia. PMID:27582690

  3. NKCC1-Deficiency Results in Abnormal Proliferation of Neural Progenitor Cells of the Lateral Ganglionic Eminence

    PubMed Central

    Magalhães, Ana Cathia; Rivera, Claudio

    2016-01-01

    The proliferative pool of neural progenitor cells is maintained by exquisitely controlled mechanisms for cell cycle regulation. The Na-K-Cl cotransporter (NKCC1) is important for regulating cell volume and the proliferation of different cell types in vitro. NKCC1 is expressed in ventral telencephalon of embryonic brains suggesting a potential role in neural development of this region. The ventral telencephalon is a major source for both interneuron and oligodendrocyte precursor cells. Whether NKCC1 is involved in the proliferation of these cell populations remains unknown. In order to assess this question, we monitored several markers for neural, neuronal, and proliferating cells in wild-type (WT) and NKCC1 knockout (KO) mouse brains. We found that NKCC1 was expressed in neural progenitor cells from the lateral ganglionic eminence (LGE) at E12.5. Mice lacking NKCC1 expression displayed reduced phospho-Histone H3 (PH3)-labeled mitotic cells in the ventricular zone (VZ) and reduced cell cycle reentry. Accordingly, we found a significant reduction of Sp8-labeled immature interneurons migrating from the dorsal LGE in NKCC1-deficient mice at a later developmental stage. Interestingly, at E14.5, NKCC1 regulated also the formation of Olig2-labeled oligodendrocyte precursor cells. Collectively, these findings show that NKCC1 serves in vivo as a modulator of the cell cycle decision in the developing ventral telencephalon at the early stage of neurogenesis. These results present a novel mechanistic avenue to be considered in the recent proposed involvement of chloride transporters in a number of developmentally related diseases, such as epilepsy, autism, and schizophrenia. PMID:27582690

  4. Genetic Dissection of Neural Circuits

    PubMed Central

    Luo, Liqun; Callaway, Edward M.; Svoboda, Karel

    2009-01-01

    Understanding the principles of information processing in neural circuits requires systematic characterization of the participating cell types and their connections, and the ability to measure and perturb their activity. Genetic approaches promise to bring experimental access to complex neural systems, including genetic stalwarts such as the fly and mouse, but also to nongenetic systems such as primates. Together with anatomical and physiological methods, cell-type-specific expression of protein markers and sensors and transducers will be critical to construct circuit diagrams and to measure the activity of genetically defined neurons. Inactivation and activation of genetically defined cell types will establish causal relationships between activity in specific groups of neurons, circuit function, and animal behavior. Genetic analysis thus promises to reveal the logic of the neural circuits in complex brains that guide behaviors. Here we review progress in the genetic analysis of neural circuits and discuss directions for future research and development. PMID:18341986

  5. OXIDANT-PRECURSOR RELATIONSHIPS

    EPA Science Inventory

    New methods of ambient air analysis were used to define more clearly the relationships between oxidants and their precursors. Non-methane hydrocarbons, NOx, O2, and oxidants were measured at the same time and location (Riverside, California). The ambient air data presented in thi...

  6. Untangling ENSO Precursors

    NASA Astrophysics Data System (ADS)

    Pegion, K.; Alexander, M. A.

    2014-12-01

    There are several proposed precursors to the El Nino-Southern Oscillation (ENSO) that may provide the ability to predict ENSO as much as one year in advance. Some of these precursors are associated with stochastic forcing from extratropical atmospheric variability. Two examples are the seasonal footprinting mechanism (SFM) and the Pacific meridional mode (PMM). Both of these ENSO precursors are thought to be forced by the North Pacific Oscillation (NPO), a north-south sea level pressure dipole in the north Pacific. Additionally, both the PMM and SFM are thought to impact the tropics through wind evaporation SST feedbacks and have a correlation with ENSO up to one year in advance. These two precursors are discussed interchangeably throughout the literature and various indices used to define them co-mingle them. As a result, whether they are independent of each other or are part of the same process has not been investigated. The research presented is focused on untangling the relationship between the PMM, SFM, NPO, and ENSO using observational datasets and model simulations. Observational results demonstrate that these two mechanisms are different, are forced by different atmospheric circulations, and result in different manifestations of ENSO. Modeling results highlight the extent to which climate models can simulate these relationships and their impact on the simulation of ENSO.

  7. Knockout of REST/NRSF shows that the protein is a potent repressor of neuronally expressed genes in non-neural tissues.

    PubMed

    Jones, F S; Meech, R

    1999-05-01

    The protein repressor element 1 silencing transcription factor/neuron restrictive silencer factor (REST/NRSF) is a negative regulator of neuronal genes that contain a particular DNA sequence, the neuron restrictive silencer element (NRSE). REST is expressed ubiquitously in non-neural tissues but is down-regulated in neural precursors and turned off in postmitotic neurons, suggesting that it can act both to prevent extraneural expression of certain genes and to delay the differentiation of neuronal subtypes. In a recent paper, Chen et al.(1) describe the production of a null mutant for REST in mice and the mosaic inactivation of REST function in chicken embryos. Knockout of REST led to malformations in several non-neural tissues, as well as apoptosis and embryonic lethality in mice. In addition, the expression of several REST target genes was derepressed in non-neural tissues and in neural progenitors in both mouse and chicken embryos. These studies clearly demonstrate that active repression of tissue-specific genes is required for proper tissue differentiation during embryonic development. PMID:10376008

  8. FolR1: a novel cell surface marker for isolating midbrain dopamine neural progenitors and nascent dopamine neurons.

    PubMed

    Gennet, Nicole; Tamburini, Claudia; Nan, Xinsheng; Li, Meng

    2016-01-01

    Cell type-specific surface markers offer a powerful tool for purifying defined cell types for restorative therapies and drug screenings. Midbrain dopaminergic neurons (mesDA) are the nerve cells preferentially lost in the brains of Parkinson's disease patients. Clinical trials of transplantation of fetal neural precursors suggest that cell therapy may offer a cure for this devastating neurological disease. Many lines of preclinical studies demonstrate that neural progenitors committed to dopaminergic fate survive and integrate better than postmitotic DA neurons. We show that the folate-receptor 1 (FolR1), a GPI-anchored cell surface molecule, specifically marks mesDA neural progenitors and immature mesDA neurons. FolR1 expression superimposes with Lmx1a, a bona-fide mesDA lineage marker, during the active phase of mesDA neurogenesis from E9.5 to E14.5 during mouse development, as well as in ESC-derived mesDA lineage. FolR1(+) neural progenitors can be isolated by FACS or magnetic sorting (MAC) which give rise to dopamine neurons expressing TH and Pitx3, whilst FolR1 negative cells generate non-dopaminergic neurons and glia cells. This study identifies FolR1 as a new cell surface marker selectively expressed in mesDA progenitors in vivo and in vitro and that can be used to enrich in vitro differentiated TH neurons. PMID:27580818

  9. FolR1: a novel cell surface marker for isolating midbrain dopamine neural progenitors and nascent dopamine neurons

    PubMed Central

    Gennet, Nicole; Tamburini, Claudia; Nan, Xinsheng; Li, Meng

    2016-01-01

    Cell type-specific surface markers offer a powerful tool for purifying defined cell types for restorative therapies and drug screenings. Midbrain dopaminergic neurons (mesDA) are the nerve cells preferentially lost in the brains of Parkinson’s disease patients. Clinical trials of transplantation of fetal neural precursors suggest that cell therapy may offer a cure for this devastating neurological disease. Many lines of preclinical studies demonstrate that neural progenitors committed to dopaminergic fate survive and integrate better than postmitotic DA neurons. We show that the folate-receptor 1 (FolR1), a GPI-anchored cell surface molecule, specifically marks mesDA neural progenitors and immature mesDA neurons. FolR1 expression superimposes with Lmx1a, a bona-fide mesDA lineage marker, during the active phase of mesDA neurogenesis from E9.5 to E14.5 during mouse development, as well as in ESC-derived mesDA lineage. FolR1+ neural progenitors can be isolated by FACS or magnetic sorting (MAC) which give rise to dopamine neurons expressing TH and Pitx3, whilst FolR1 negative cells generate non-dopaminergic neurons and glia cells. This study identifies FolR1 as a new cell surface marker selectively expressed in mesDA progenitors in vivo and in vitro and that can be used to enrich in vitro differentiated TH neurons. PMID:27580818

  10. Zika Virus Disrupts Neural Progenitor Development and Leads to Microcephaly in Mice.

    PubMed

    Li, Cui; Xu, Dan; Ye, Qing; Hong, Shuai; Jiang, Yisheng; Liu, Xinyi; Zhang, Nana; Shi, Lei; Qin, Cheng-Feng; Xu, Zhiheng

    2016-07-01

    The link between Zika virus (ZIKV) infection and microcephaly has raised urgent global alarm. The historical African ZIKV MR766 was recently shown to infect cultured human neural precursor cells (NPCs), but unlike the contemporary ZIKV strains, it is not believed to cause microcephaly. Here we investigated whether the Asian ZIKV strain SZ01 could infect NPCs in vivo and affect brain development. We found that SZ01 replicates efficiently in embryonic mouse brain by directly targeting different neuronal linages. ZIKV infection leads to cell-cycle arrest, apoptosis, and inhibition of NPC differentiation, resulting in cortical thinning and microcephaly. Global gene expression analysis of infected brains reveals upregulation of candidate flavirus entry receptors and dysregulation of genes associated with immune response, apoptosis, and microcephaly. Our model provides evidence for a direct link between Zika virus infection and microcephaly, with potential for further exploration of the underlying mechanisms and management of ZIKV-related pathological effects during brain development. PMID:27179424

  11. Differential gene expression and functional analysis implicates novel mechanisms in enteric nervous system precursor migration and neuritogenesis

    PubMed Central

    Vohra, Bhupinder P.S.; Tsuji, Keiji; Nagashimada, Mayumi; Uesaka, Toshihiro; Wind, Daniel; Armon, Jennifer; Enomoto, Hideki; Heuckeroth, Robert O.

    2007-01-01

    Enteric nervous system (ENS) development requires complex interactions between migrating neural crest-derived cells and the intestinal microenvironment. Although some molecules influencing ENS development are known, many aspects remain poorly understood. To identify additional molecules critical for ENS development, we used DNA microarray, quantitative real time PCR and in situ hybridization to compare gene expression in E14 and P0 aganglionic or wild type mouse intestine. 83 genes were identified with twofold higher expression in wild type than aganglionic bowel. ENS expression was verified for 39 of 42 selected genes by in situ hybridization. Additionally, nine identified genes had higher levels in aganglionic bowel than in WT animals suggesting that intestinal innervation may influence gene expression in adjacent cells. Strikingly, many synaptic function genes were expressed at E14, a time when the ENS is not needed for survival. To test for developmental roles for these genes, we used pharmacologic inhibitors of Snap25 or vesicle associated membrane protein (VAMP)/synaptobrevin and found reduced neural crest-derived cell migration and decreased neurite extension from ENS precursors. These results provide an extensive set of ENS biomarkers, demonstrate a role for SNARE proteins in ENS development and highlight additional candidate genes that could modify Hirschsprung’s disease penetrance. PMID:16904662

  12. Dystroglycan protein distribution coincides with basement membranes and muscle differentiation during mouse embryogenesis.

    PubMed

    Anderson, Claire; Winder, Steven J; Borycki, Anne-Gaëlle

    2007-09-01

    Using immunohistochemistry, we have examined beta-Dystroglycan protein distribution in the mouse embryo at embryonic stages E9.5 to E11.5. Our data show that Dystroglycan expression correlates with basement membranes in many tissues, such as the notochord, neural tube, promesonephros, and myotome. In the myotome, we describe the timing of Dystroglycan protein re-distribution at the surface of myogenic precursor cells as basement membrane assembles into a continuous sheet. We also report on non-basement-membrane-associated Dystroglycan expression in the floor plate and the myocardium. This distribution often corresponds to sites of expression previously reported in adults, suggesting that Dystroglycan is continuously produced during development. PMID:17676646

  13. The EM Earthquake Precursor

    NASA Astrophysics Data System (ADS)

    Jones, K. B., II; Saxton, P. T.

    2013-12-01

    Many attempts have been made to determine a sound forecasting method regarding earthquakes and warn the public in turn. Presently, the animal kingdom leads the precursor list alluding to a transmission related source. By applying the animal-based model to an electromagnetic (EM) wave model, various hypotheses were formed, but the most interesting one required the use of a magnetometer with a differing design and geometry. To date, numerous, high-end magnetometers have been in use in close proximity to fault zones for potential earthquake forecasting; however, something is still amiss. The problem still resides with what exactly is forecastable and the investigating direction of EM. After the 1989 Loma Prieta Earthquake, American earthquake investigators predetermined magnetometer use and a minimum earthquake magnitude necessary for EM detection. This action was set in motion, due to the extensive damage incurred and public outrage concerning earthquake forecasting; however, the magnetometers employed, grounded or buried, are completely subject to static and electric fields and have yet to correlate to an identifiable precursor. Secondly, there is neither a networked array for finding any epicentral locations, nor have there been any attempts to find even one. This methodology needs dismissal, because it is overly complicated, subject to continuous change, and provides no response time. As for the minimum magnitude threshold, which was set at M5, this is simply higher than what modern technological advances have gained. Detection can now be achieved at approximately M1, which greatly improves forecasting chances. A propagating precursor has now been detected in both the field and laboratory. Field antenna testing conducted outside the NE Texas town of Timpson in February, 2013, detected three strong EM sources along with numerous weaker signals. The antenna had mobility, and observations were noted for recurrence, duration, and frequency response. Next, two

  14. Generalized Potential of Adult Neural Stem Cells

    NASA Astrophysics Data System (ADS)

    Clarke, Diana L.; Johansson, Clas B.; Wilbertz, Johannes; Veress, Biborka; Nilsson, Erik; Karlström, Helena; Lendahl, Urban; Frisén, Jonas

    2000-06-01

    The differentiation potential of stem cells in tissues of the adult has been thought to be limited to cell lineages present in the organ from which they were derived, but there is evidence that some stem cells may have a broader differentiation repertoire. We show here that neural stem cells from the adult mouse brain can contribute to the formation of chimeric chick and mouse embryos and give rise to cells of all germ layers. This demonstrates that an adult neural stem cell has a very broad developmental capacity and may potentially be used to generate a variety of cell types for transplantation in different diseases.

  15. Insulin-like Growth Factor-II (IGF-II) and IGF-II Analogs with Enhanced Insulin Receptor-a Binding Affinity Promote Neural Stem Cell Expansion*

    PubMed Central

    Ziegler, Amber N.; Chidambaram, Shravanthi; Forbes, Briony E.; Wood, Teresa L.; Levison, Steven W.

    2014-01-01

    The objective of this study was to employ genetically engineered IGF-II analogs to establish which receptor(s) mediate the stemness promoting actions of IGF-II on mouse subventricular zone neural precursors. Neural precursors from the subventricular zone were propagated in vitro in culture medium supplemented with IGF-II analogs. Cell growth and identity were analyzed using sphere generation and further analyzed by flow cytometry. F19A, an analog of IGF-II that does not bind the IGF-2R, stimulated an increase in the proportion of neural stem cells (NSCs) while decreasing the proportion of the later stage progenitors at a lower concentration than IGF-II. V43M, which binds to the IGF-2R with high affinity but which has low binding affinity to the IGF-1R and to the A isoform of the insulin receptor (IR-A) failed to promote NSC growth. The positive effects of F19A on NSC growth were unaltered by the addition of a functional blocking antibody to the IGF-1R. Altogether, these data lead to the conclusion that IGF-II promotes stemness of NSCs via the IR-A and not through activation of either the IGF-1R or the IGF-2R. PMID:24398690

  16. Vascular Precursor Cells

    PubMed Central

    Chaudhury, Hera; Goldie, Lauren C.

    2011-01-01

    Understanding the mechanisms that regulate the proliferation and differentiation of human stem and progenitor cells is critically important for the development and optimization of regenerative medicine strategies. For vascular regeneration studies, specifically, a true “vascular stem cell” population has not yet been identified. However, a number of cell types that exist endogenously, or can be generated or propagated ex vivo, function as vascular precursor cells and can participate in and/or promote vascular regeneration. Herein, we provide an overview of what is known about the regulation of their differentiation specifically toward a vascular endothelial cell phenotype. PMID:22866199

  17. Contribution of Underlying Connective Tissue Cells to Taste Buds in Mouse Tongue and Soft Palate

    PubMed Central

    Mederacke, Ingmar; Komatsu, Yoshihiro; Stice, Steve; Schwabe, Robert F.; Mistretta, Charlotte M.; Mishina, Yuji; Liu, Hong-Xiang

    2016-01-01

    Taste buds, the sensory organs for taste, have been described as arising solely from the surrounding epithelium, which is in distinction from other sensory receptors that are known to originate from neural precursors, i.e., neural ectoderm that includes neural crest (NC). Our previous study suggested a potential contribution of NC derived cells to early immature fungiform taste buds in late embryonic (E18.5) and young postnatal (P1-10) mice. In the present study we demonstrated the contribution of the underlying connective tissue (CT) to mature taste buds in mouse tongue and soft palate. Three independent mouse models were used for fate mapping of NC and NC derived connective tissue cells: (1) P0-Cre/R26-tdTomato (RFP) to label NC, NC derived Schwann cells and derivatives; (2) Dermo1-Cre/RFP to label mesenchymal cells and derivatives; and (3) Vimentin-CreER/mGFP to label Vimentin-expressing CT cells and derivatives upon tamoxifen treatment. Both P0-Cre/RFP and Dermo1-Cre/RFP labeled cells were abundant in mature taste buds in lingual taste papillae and soft palate, but not in the surrounding epithelial cells. Concurrently, labeled cells were extensively distributed in the underlying CT. RFP signals were seen in the majority of taste buds and all three types (I, II, III) of differentiated taste bud cells, with the neuronal-like type III cells labeled at a greater proportion. Further, Vimentin-CreER labeled cells were found in the taste buds of 3-month-old mice whereas Vimentin immunoreactivity was only seen in the CT. Taken together, our data demonstrate a previously unrecognized origin of taste bud cells from the underlying CT, a conceptually new finding in our knowledge of taste bud cell derivation, i.e., from both the surrounding epithelium and the underlying CT that is primarily derived from NC. PMID:26741369

  18. Tcf7l1 protects the anterior neural fold from adopting the neural crest fate.

    PubMed

    Mašek, Jan; Machoň, Ondřej; Kořínek, Vladimír; Taketo, M Mark; Kozmik, Zbyněk

    2016-06-15

    The neural crest (NC) is crucial for the evolutionary diversification of vertebrates. NC cells are induced at the neural plate border by the coordinated action of several signaling pathways, including Wnt/β-catenin. NC cells are normally generated in the posterior neural plate border, whereas the anterior neural fold is devoid of NC cells. Using the mouse model, we show here that active repression of Wnt/β-catenin signaling is required for maintenance of neuroepithelial identity in the anterior neural fold and for inhibition of NC induction. Conditional inactivation of Tcf7l1, a transcriptional repressor of Wnt target genes, leads to aberrant activation of Wnt/β-catenin signaling in the anterior neuroectoderm and its conversion into NC. This reduces the developing prosencephalon without affecting the anterior-posterior neural character. Thus, Tcf7l1 defines the border between the NC and the prospective forebrain via restriction of the Wnt/β-catenin signaling gradient. PMID:27302397

  19. Evolvable synthetic neural system

    NASA Technical Reports Server (NTRS)

    Curtis, Steven A. (Inventor)

    2009-01-01

    An evolvable synthetic neural system includes an evolvable neural interface operably coupled to at least one neural basis function. Each neural basis function includes an evolvable neural interface operably coupled to a heuristic neural system to perform high-level functions and an autonomic neural system to perform low-level functions. In some embodiments, the evolvable synthetic neural system is operably coupled to one or more evolvable synthetic neural systems in a hierarchy.

  20. Cochlear precursors of neural pitch and loudness codes.

    PubMed

    Zwislocki, J J

    1995-09-01

    It has been believed by most auditory scientists for over a century that the place of maximum vibration in the cochlea provides the main pitch code. Recently, we have obtained experimental evidence showing that this is quite unlikely, because the maximum of cochlear excitation changes its location with sound intensity, moving over the useful sound intensity range toward the cochlear base by a distance equivalent to more than one octave, whereas the pitch remains almost constant. In the presence of outer hair cell damage, the maximum is shifted toward the base by a similar distance, whereas the pitch is hardly affected. Of interest, the location of the apical cutoff of excitation is practically unaffected by sound intensity or cochlear damage. For any given sound frequency, the shift of the maximum with sound intensity precludes any single cochlear location from coding for loudness over the entire useful intensity range. The code is very likely provided by the maximum, which changes its location with the intensity, or by the whole cochlear excitation area. Of significance in this respect is our determination that the growth of the output of the whole auditory nerve parallels the growth of the excitation area. These findings may be useful for the coding of sound in cochlear implants, as well as for hearing aid dynamics. PMID:7668600

  1. Neural Networks

    SciTech Connect

    Smith, Patrick I.

    2003-09-23

    Physicists use large detectors to measure particles created in high-energy collisions at particle accelerators. These detectors typically produce signals indicating either where ionization occurs along the path of the particle, or where energy is deposited by the particle. The data produced by these signals is fed into pattern recognition programs to try to identify what particles were produced, and to measure the energy and direction of these particles. Ideally, there are many techniques used in this pattern recognition software. One technique, neural networks, is particularly suitable for identifying what type of particle caused by a set of energy deposits. Neural networks can derive meaning from complicated or imprecise data, extract patterns, and detect trends that are too complex to be noticed by either humans or other computer related processes. To assist in the advancement of this technology, Physicists use a tool kit to experiment with several neural network techniques. The goal of this research is interface a neural network tool kit into Java Analysis Studio (JAS3), an application that allows data to be analyzed from any experiment. As the final result, a physicist will have the ability to train, test, and implement a neural network with the desired output while using JAS3 to analyze the results or output. Before an implementation of a neural network can take place, a firm understanding of what a neural network is and how it works is beneficial. A neural network is an artificial representation of the human brain that tries to simulate the learning process [5]. It is also important to think of the word artificial in that definition as computer programs that use calculations during the learning process. In short, a neural network learns by representative examples. Perhaps the easiest way to describe the way neural networks learn is to explain how the human brain functions. The human brain contains billions of neural cells that are responsible for processing

  2. An interstellar precursor mission

    NASA Technical Reports Server (NTRS)

    Jaffe, L. D.; Ivie, C.; Lewis, J. C.; Lipes, R. G.; Norton, H. N.; Stearns, J. W.; Stimpson, L.; Weissman, P.

    1977-01-01

    A mission out of the planetary system, with launch about the year 2000, could provide valuable scientific data as well as test some of the technology for a later mission to another star. Primary scientific objectives for the precursor mission concern characteristics of the heliopause, the interstellar medium, stellar distances (by parallax measurements), low energy cosmic rays, interplanetary gas distribution, and mass of the solar system. Secondary objectives include investigation of Pluto. Candidate science instruments are suggested. Individual spacecraft systems for the mission were considered, technology requirements and problem areas noted, and a number of recommendations made for technology study and advanced development. The most critical technology needs include attainment of 50-yr spacecraft lifetime and development of a long-life NEP system.

  3. Identified EM Earthquake Precursors

    NASA Astrophysics Data System (ADS)

    Jones, Kenneth, II; Saxton, Patrick

    2014-05-01

    Many attempts have been made to determine a sound forecasting method regarding earthquakes and warn the public in turn. Presently, the animal kingdom leads the precursor list alluding to a transmission related source. By applying the animal-based model to an electromagnetic (EM) wave model, various hypotheses were formed, but the most interesting one required the use of a magnetometer with a differing design and geometry. To date, numerous, high-end magnetometers have been in use in close proximity to fault zones for potential earthquake forecasting; however, something is still amiss. The problem still resides with what exactly is forecastable and the investigating direction of EM. After a number of custom rock experiments, two hypotheses were formed which could answer the EM wave model. The first hypothesis concerned a sufficient and continuous electron movement either by surface or penetrative flow, and the second regarded a novel approach to radio transmission. Electron flow along fracture surfaces was determined to be inadequate in creating strong EM fields, because rock has a very high electrical resistance making it a high quality insulator. Penetrative flow could not be corroborated as well, because it was discovered that rock was absorbing and confining electrons to a very thin skin depth. Radio wave transmission and detection worked with every single test administered. This hypothesis was reviewed for propagating, long-wave generation with sufficient amplitude, and the capability of penetrating solid rock. Additionally, fracture spaces, either air or ion-filled, can facilitate this concept from great depths and allow for surficial detection. A few propagating precursor signals have been detected in the field occurring with associated phases using custom-built loop antennae. Field testing was conducted in Southern California from 2006-2011, and outside the NE Texas town of Timpson in February, 2013. The antennae have mobility and observations were noted for

  4. Generation of Nonlinear Vortex Precursors.

    PubMed

    Chen, Yue-Yue; Feng, Xun-Li; Liu, Chengpu

    2016-07-01

    We numerically study the propagation of a few-cycle pulse carrying orbital angular momentum (OAM) through a dense atomic system. Nonlinear precursors consisting of high-order vortex harmonics are generated in the transmitted field due to carrier effects associated with ultrafast Bloch oscillation. The nonlinear precursors survive to propagation effects and are well separated with the main pulse, which provides a straightforward way to measure precursors. By virtue of carrying high-order OAM, the obtained vortex precursors as information carriers have potential applications in optical information and communication fields where controllable loss, large information-carrying capacity, and high speed communication are required. PMID:27447507

  5. Generation of Nonlinear Vortex Precursors

    NASA Astrophysics Data System (ADS)

    Chen, Yue-Yue; Feng, Xun-Li; Liu, Chengpu

    2016-07-01

    We numerically study the propagation of a few-cycle pulse carrying orbital angular momentum (OAM) through a dense atomic system. Nonlinear precursors consisting of high-order vortex harmonics are generated in the transmitted field due to carrier effects associated with ultrafast Bloch oscillation. The nonlinear precursors survive to propagation effects and are well separated with the main pulse, which provides a straightforward way to measure precursors. By virtue of carrying high-order OAM, the obtained vortex precursors as information carriers have potential applications in optical information and communication fields where controllable loss, large information-carrying capacity, and high speed communication are required.

  6. Stat3 inhibition in neural lineage cells.

    PubMed

    Chiba, Tomohiro; Mack, Laura; Delis, Natalia; Brill, Boris; Groner, Bernd

    2012-06-01

    Abstract Deregulation of signal transducer and activator of transcription 3 (Stat3) is attracting attentions in neurological disorders of elderly populations, e.g., Stat3 is inactivated in hippocampal neurons of Alzheimer's disease (AD) brains, whereas it is often constitutively activated in glioblastoma multiforme (GBM), correlating with poor prognosis. Stat3-inhibiting drugs have been intensively developed for chemotherapy based on the fact that GBM, in many cases, are "addicted" to Stat3 activation. Stat3 inhibitors, however, potentially have unfavorable side effects on postmitotic neurons, normal permanent residents in the central nervous system. It is, therefore, of great importance to address detailed cellular responses of neural lineage cells including normal neurons, astrocytes, and neuronal/glial cancer cell lines to several classes of Stat3 inhibitors focusing on their effective concentrations. Here, we picked up five human and mouse cancer cell lines (Neuro-2a and SH-SY5Y neuroblastoma cell lines and Tu-9648, U-87MG, and U-373MG glioblastoma cell lines) and treated with various Stat3 inhibitors. Among them, Stattic, FLLL31, and resveratrol potently suppressed P-Stat3 and cell viability in all the tested cell lines. Stat3 knockdown or expression of dominant-negative Stat3 further sensitized cells to the inhibitors. Expression of familial AD-related mutant amyloid precursor protein sensitized neuronal cells, not glial cells, to Stat3 inhibitors by reducing P-Stat3 levels. Primary neurons and astrocytes also responded to Stat3 inhibitors with similar sensitivities to those observed in cancer cell lines. Thus, Stat3 inhibitors should be carefully targeted to GBM cells to avoid potential neurotoxicity leading to AD-like neuropsychiatric dysfunctions. PMID:25436682

  7. Could MDMA Promote Stemness Characteristics in Mouse Embryonic Stem Cells via mGlu5 Metabotropic Glutamate Receptors?

    PubMed Central

    Meamar, Rokhsareh; Karamali, Fereshte; Mousavi, Seyed Ali; Baharvand, Hossein; Nasr-Esfahani, Mohammad Hossein

    2012-01-01

    Objective: Ecstasy, or 3, 4 (±) methylenedioxymethamphetamine (MDMA), is a potent neurotoxic drug. One of the mechanisms for its toxicity is the secondary release of glutamate. Mouse embryonic stem cells (mESCs) express only one glutamate receptor, the metabotropic glutamate receptor 5 (mGlu5), which is involved in the maintenance and self-renewal of mESCs. This study aims to investigate whether MDMA could influence self-renewal via the mGlu5 receptor in mESCs. Materials and Methods: In this expremental study, we used immunocytochemistry and reverse transcription-polymerase chain reaction (RT-PCR) to determine the presence of the mGlu5 receptor in mESCs. The expression of mGlu5 was evaluated after MDMA was added to mESCs throughout neural precursor cell formation as group 1 and during neural precursor cell differentiation as group 2. The stemness characteristic in treated mESCs by immunofluorescence and flow cytometry was studied. Finally, caspase activity was evaluated by fluorescence staining in the treated group. One-way ANOVA or repeated measure of ANOVA according to the experimental design was used for statistical analyses. Results: In this study mGlu5 expression was shown in mESCs. In terms of neuronal differentiation, MDMA affected mGlu5 expression during neural precursor cell formation (group 1) and not during neural precursor differentiation (group 2). MDMA (450 µM) induced a significant increment in self-renewal properties in mESCs but did not reverse 2-methyl-6(phenylethynyl) pyridine (MPEP, 1 µM), a non-competitive selective mGlu5 antagonist. Fluorescence staining with anti-caspase 3 showed a significant increase in the number of apoptotic cells in the MDMA group. Conclusion: We observed a dual role for MDMA on mESCs: reduced proliferation and maintenance of self-renewal. The lack of decreasing stemness characteristic in presence of MPEP suggests that MDMA mediates its role through a different mechanism that requires further investigation. In

  8. In vivo optical modulation of neural signals using monolithically integrated two-dimensional neural probe arrays.

    PubMed

    Son, Yoojin; Lee, Hyunjoo Jenny; Kim, Jeongyeon; Shin, Hyogeun; Choi, Nakwon; Lee, C Justin; Yoon, Eui-Sung; Yoon, Euisik; Wise, Kensall D; Kim, Tae Geun; Cho, Il-Joo

    2015-01-01

    Integration of stimulation modalities (e.g. electrical, optical, and chemical) on a large array of neural probes can enable an investigation of important underlying mechanisms of brain disorders that is not possible through neural recordings alone. Furthermore, it is important to achieve this integration of multiple functionalities in a compact structure to utilize a large number of the mouse models. Here we present a successful optical modulation of in vivo neural signals of a transgenic mouse through our compact 2D MEMS neural array (optrodes). Using a novel fabrication method that embeds a lower cladding layer in a silicon substrate, we achieved a thin silicon 2D optrode array that is capable of delivering light to multiple sites using SU-8 as a waveguide core. Without additional modification to the microelectrodes, the measured impedance of the multiple microelectrodes was below 1 MΩ at 1 kHz. In addition, with a low background noise level (± 25 μV), neural spikes from different individual neurons were recorded on each microelectrode. Lastly, we successfully used our optrodes to modulate the neural activity of a transgenic mouse through optical stimulation. These results demonstrate the functionality of the 2D optrode array and its potential as a next-generation tool for optogenetic applications. PMID:26494437

  9. In vivo optical modulation of neural signals using monolithically integrated two-dimensional neural probe arrays

    PubMed Central

    Son, Yoojin; Jenny Lee, Hyunjoo; Kim, Jeongyeon; Shin, Hyogeun; Choi, Nakwon; Justin Lee, C.; Yoon, Eui-Sung; Yoon, Euisik; Wise, Kensall D.; Geun Kim, Tae; Cho, Il-Joo

    2015-01-01

    Integration of stimulation modalities (e.g. electrical, optical, and chemical) on a large array of neural probes can enable an investigation of important underlying mechanisms of brain disorders that is not possible through neural recordings alone. Furthermore, it is important to achieve this integration of multiple functionalities in a compact structure to utilize a large number of the mouse models. Here we present a successful optical modulation of in vivo neural signals of a transgenic mouse through our compact 2D MEMS neural array (optrodes). Using a novel fabrication method that embeds a lower cladding layer in a silicon substrate, we achieved a thin silicon 2D optrode array that is capable of delivering light to multiple sites using SU-8 as a waveguide core. Without additional modification to the microelectrodes, the measured impedance of the multiple microelectrodes was below 1 MΩ at 1 kHz. In addition, with a low background noise level (±25 μV), neural spikes from different individual neurons were recorded on each microelectrode. Lastly, we successfully used our optrodes to modulate the neural activity of a transgenic mouse through optical stimulation. These results demonstrate the functionality of the 2D optrode array and its potential as a next-generation tool for optogenetic applications. PMID:26494437

  10. In vivo optical modulation of neural signals using monolithically integrated two-dimensional neural probe arrays

    NASA Astrophysics Data System (ADS)

    Son, Yoojin; Jenny Lee, Hyunjoo; Kim, Jeongyeon; Shin, Hyogeun; Choi, Nakwon; Justin Lee, C.; Yoon, Eui-Sung; Yoon, Euisik; Wise, Kensall D.; Geun Kim, Tae; Cho, Il-Joo

    2015-10-01

    Integration of stimulation modalities (e.g. electrical, optical, and chemical) on a large array of neural probes can enable an investigation of important underlying mechanisms of brain disorders that is not possible through neural recordings alone. Furthermore, it is important to achieve this integration of multiple functionalities in a compact structure to utilize a large number of the mouse models. Here we present a successful optical modulation of in vivo neural signals of a transgenic mouse through our compact 2D MEMS neural array (optrodes). Using a novel fabrication method that embeds a lower cladding layer in a silicon substrate, we achieved a thin silicon 2D optrode array that is capable of delivering light to multiple sites using SU-8 as a waveguide core. Without additional modification to the microelectrodes, the measured impedance of the multiple microelectrodes was below 1 MΩ at 1 kHz. In addition, with a low background noise level (±25 μV), neural spikes from different individual neurons were recorded on each microelectrode. Lastly, we successfully used our optrodes to modulate the neural activity of a transgenic mouse through optical stimulation. These results demonstrate the functionality of the 2D optrode array and its potential as a next-generation tool for optogenetic applications.

  11. An interstellar precursor mission

    NASA Technical Reports Server (NTRS)

    Jaffe, L. D.; Ivie, C.; Lewis, J. C.; Lipes, R.; Norton, H. N.; Stearns, J. W.; Stimpson, L. D.; Weissman, P.

    1980-01-01

    A mission out of the planetary system, launched about the year 2000, could provide valuable scientific data as well as test some of the technology for a later mission to another star. Primary scientific objectives for the precursor mission concern characteristics of the heliopause, the interstellar medium, stellar distances (by parallax measurements), low-energy cosmic rays, interplanetary gas distribution, and the mass of the solar system. Secondary objectives include investigation of Pluto. The mission should extend to 400-1000 AU from the sun. A heliocentric hyperbolic escape velocity of 50-100 km/sec or more is needed to attain this distance within a reasonable mission duration (20-50 years). The trajectory should be toward the incoming interstellar gas. For a year 2000 launch, a Pluto encounter and orbiter can be included. A second mission targeted parallel to the solar axis would also be worthwhile. The mission duration is 20 years, with an extended mission to a total of 50 years. A system using one or two stages of nuclear electric propulsion (NEP) was selected as a possible baseline. The most promising alternatives are ultralight solar sails or laser sailing, with the lasers in earth orbit, for example. The NEP baseline design allows the option of carrying a Pluto orbiter as a daughter spacecraft.

  12. Musashi1-CreERT2: A New Cre Line for Conditional Mutagenesis in Neural Stem Cells

    PubMed Central

    Takeda, Haruna; Koso, Hideto; Tessarollo, Lino; Copeland, Neal G.; Jenkins, Nancy A.

    2012-01-01

    The RNA-binding protein Musashi1 (Msi1) is one of two mammalian homologues of Drosophila Musashi, which is required for the asymmetric cell division of sensory organ precursor cells. In the mouse central nervous system (CNS) Msi1 is preferentially expressed in mitotically active progenitor cells in the ventricular zone (VZ) of the neural tube during embryonic development and in the subventricular zone (SVZ) of the postnatal brain. Previous studies showed that cells in the SVZ can contribute to long-term neurogenesis in the olfactory bulb (OB) but it remains unclear whether Msi1-expressing cells have self-renewing potential and can contribute to neurogenesis in the adult. Here we describe the generation of Msi1-CreERT2 knock-in mice and show by cell lineage tracing that Msi1-CreERT2-expressing cells mark neural stem cells (NSCs) in both the embryonic and adult brain. Msi1-CreERT2 mice thus represent a new tool in our arsenal for genetically manipulating NSCs, which will be essential for understanding the molecular mechanisms underlying neural development. PMID:23132814

  13. Maintenance of neural stem cell regional identity in culture.

    PubMed

    Delgado, Ryan N; Lu, Changqing; Lim, Daniel A

    2016-01-01

    Neural stem cells (NSCs) are distributed throughout the ventricular-subventricular zone (V-SVZ) in the adult mouse brain. NSCs located in spatially distinct regions of the V-SVZ generate different types of olfactory bulb (OB) neurons, and the regional expression of specific transcription factors correlates with these differences in NSC developmental potential. In a recent article, we show that Nkx2.1-expressing embryonic precursors give rise to NKX2.1+ NSCs located in the ventral V-SVZ of adult mice. Here we characterize a V-SVZ monolayer culture system that retains regional gene expression and neurogenic potential of NSCs from the dorsal and ventral V-SVZ. In particular, we find that Nkx2.1-lineage V-SVZ NSCs maintain Nkx2.1 expression through serial passage and can generate new neurons in vitro. Thus, V-SVZ NSCs retain key aspects of their in vivo regional identity in culture, providing new experimental opportunities for understanding how such developmental patterns are established and maintained during development. PMID:27606338

  14. Neural differentiation and synaptogenesis in retinal development.

    PubMed

    Fan, Wen-Juan; Li, Xue; Yao, Huan-Ling; Deng, Jie-Xin; Liu, Hong-Liang; Cui, Zhan-Jun; Wang, Qiang; Wu, Ping; Deng, Jin-Bo

    2016-02-01

    To investigate the pattern of neural differentiation and synaptogenesis in the mouse retina, immunolabeling, BrdU assay and transmission electron microscopy were used. We show that the neuroblastic cell layer is the germinal zone for neural differentiation and retinal lamination. Ganglion cells differentiated initially at embryonic day 13 (E13), and at E18 horizontal cells appeared in the neuroblastic cell layer. Neural stem cells in the outer neuroblastic cell layer differentiated into photoreceptor cells as early as postnatal day 0 (P0), and neural stem cells in the inner neuroblastic cell layer differentiated into bipolar cells at P7. Synapses in the retina were mainly located in the outer and inner plexiform layers. At P7, synaptophysin immunostaining appeared in presynaptic terminals in the outer and inner plexiform layers with button-like structures. After P14, presynaptic buttons were concentrated in outer and inner plexiform layers with strong staining. These data indicate that neural differentiation and synaptogenesis in the retina play important roles in the formation of retinal neural circuitry. Our study showed that the period before P14, especially between P0 and P14, represents a critical period during retinal development. Mouse eye opening occurs during that period, suggesting that cell differentiation and synaptic formation lead to the attainment of visual function. PMID:27073386

  15. Neural differentiation and synaptogenesis in retinal development

    PubMed Central

    Fan, Wen-juan; Li, Xue; Yao, Huan-ling; Deng, Jie-xin; Liu, Hong-liang; Cui, Zhan-jun; Wang, Qiang; Wu, Ping; Deng, Jin-bo

    2016-01-01

    To investigate the pattern of neural differentiation and synaptogenesis in the mouse retina, immunolabeling, BrdU assay and transmission electron microscopy were used. We show that the neuroblastic cell layer is the germinal zone for neural differentiation and retinal lamination. Ganglion cells differentiated initially at embryonic day 13 (E13), and at E18 horizontal cells appeared in the neuroblastic cell layer. Neural stem cells in the outer neuroblastic cell layer differentiated into photoreceptor cells as early as postnatal day 0 (P0), and neural stem cells in the inner neuroblastic cell layer differentiated into bipolar cells at P7. Synapses in the retina were mainly located in the outer and inner plexiform layers. At P7, synaptophysin immunostaining appeared in presynaptic terminals in the outer and inner plexiform layers with button-like structures. After P14, presynaptic buttons were concentrated in outer and inner plexiform layers with strong staining. These data indicate that neural differentiation and synaptogenesis in the retina play important roles in the formation of retinal neural circuitry. Our study showed that the period before P14, especially between P0 and P14, represents a critical period during retinal development. Mouse eye opening occurs during that period, suggesting that cell differentiation and synaptic formation lead to the attainment of visual function. PMID:27073386

  16. The Survival of Engrafted Neural Stem Cells Within Hyaluronic Acid Hydrogels

    PubMed Central

    Liang, Yajie; Walczak, Piotr; Bulte, Jeff W.M.

    2013-01-01

    Successful cell-based therapy of neurological disorders is highly dependent on the survival of transplanted stem cells, with the overall graft survival of naked, unprotected cells in general remaining poor. We investigated the use of an injectable hyaluronic acid (HA) hydrogel for enhancement of survival of transplanted mouse C17.2 cells, human neural progenitor cells (ReNcells), and human glial-restricted precursors (GRPs). The gelation properties of the HA hydrogel were first characterized and optimized for intracerebral injection, resulting in a 25 min delayed-injection after mixing of the hydrogel components. Using bioluminescence imaging (BLI) as a non-invasive readout of cell survival, we found that the hydrogel can protect xenografted cells as evidenced by the prolonged survival of C17.2 cells implanted in immunocompetent rats (p<0.01 at day 12). The survival of human ReNcells and human GRPs implanted in the brain of immunocompetent or immunodeficient mice was also significantly improved after hydrogel scaffolding (ReNcells, p<0.05 at day 5; GRPs, p<0.05 at day 7). However, an inflammatory response could be noted two weeks after injection of hydrogel into immunocompetent mice brains. We conclude that hydrogel scaffolding increases the survival of engrafted neural stem cells, justifying further optimization of hydrogel compositions. PMID:23623429

  17. Signals that regulate the oncogenic fate of neural stem cells and progenitors.

    PubMed

    Swartling, Fredrik J; Bolin, Sara; Phillips, Joanna J; Persson, Anders I

    2014-10-01

    Brain tumors have frequently been associated with a neural stem cell (NSC) origin and contain stem-like tumor cells, so-called brain tumor stem cells (BTSCs) that share many features with normal NSCs. A stem cell state of BTSCs confers resistance to radiotherapy and treatment with alkylating agents. It is also a hallmark of aggressive brain tumors and is maintained by transcriptional networks that are also active in embryonic stem cells. Advances in reprogramming of somatic cells into induced pluripotent stem (iPS) cells have further identified genes that drive stemness. In this review, we will highlight the possible drivers of stemness in medulloblastoma and glioma, the most frequent types of primary malignant brain cancer in children and adults, respectively. Signals that drive expansion of developmentally defined neural precursor cells are also active in corresponding brain tumors. Transcriptomal subgroups of human medulloblastoma and glioma match features of NSCs but also more restricted progenitors. Lessons from genetically-engineered mouse (GEM) models show that temporally and regionally defined NSCs can give rise to distinct subgroups of medulloblastoma and glioma. We will further discuss how acquisition of stem cell features may drive brain tumorigenesis from a non-NSC origin. Genetic alterations, signaling pathways, and therapy-induced changes in the tumor microenvironment can drive reprogramming networks and induce stemness in brain tumors. Finally, we propose a model where dysregulation of microRNAs (miRNAs) that normally provide barriers against reprogramming plays an integral role in promoting stemness in brain tumors. PMID:23376224

  18. Glial cells in the mouse enteric nervous system can undergo neurogenesis in response to injury

    PubMed Central

    Laranjeira, Catia; Sandgren, Katarina; Kessaris, Nicoletta; Richardson, William; Potocnik, Alexandre; Vanden Berghe, Pieter; Pachnis, Vassilis

    2011-01-01

    The enteric nervous system (ENS) in mammals forms from neural crest cells during embryogenesis and early postnatal life. Nevertheless, multipotent progenitors of the ENS can be identified in the adult intestine using clonal cultures and in vivo transplantation assays. The identity of these neurogenic precursors in the adult gut and their relationship to the embryonic progenitors of the ENS are currently unknown. Using genetic fate mapping, we here demonstrate that mouse neural crest cells marked by SRY box–containing gene 10 (Sox10) generate the neuronal and glial lineages of enteric ganglia. Most neurons originated from progenitors residing in the gut during mid-gestation. Afterward, enteric neurogenesis was reduced, and it ceased between 1 and 3 months of postnatal life. Sox10-expressing cells present in the myenteric plexus of adult mice expressed glial markers, and we found no evidence that these cells participated in neurogenesis under steady-state conditions. However, they retained neurogenic potential, as they were capable of generating neurons with characteristics of enteric neurons in culture. Furthermore, enteric glia gave rise to neurons in vivo in response to chemical injury to the enteric ganglia. Our results indicate that despite the absence of constitutive neurogenesis in the adult gut, enteric glia maintain limited neurogenic potential, which can be activated by tissue dissociation or injury. PMID:21865647

  19. Serotonin uptake, storage, and synthesis in an immortalized committed cell line derived from mouse teratocarcinoma.

    PubMed Central

    Buc-Caron, M H; Launay, J M; Lamblin, D; Kellermann, O

    1990-01-01

    We report the isolation and characterization of a serotoninergic cell line, 1C11, derived from a mouse teratocarcinoma. The clone 1C11 was immortalized through the expression of the simian virus 40 oncogenes. 1C11 presents two states: an immature epithelial-like state (1C11 precursor) and a more differentiated state (1C11). After induction by dibutyryl cyclic AMP and cyclohexanecarboxylic acid, almost 100% of 1C11 cells continue to divide and have acquired a neural-like phenotype. 1C11* cells coexpress several neural markers, such as synaptophysin (the membrane constituent of synaptic vesicles), the neuropeptide [Met5]enkephalin, and the neurotransmitter serotonin. 1C11* cells store endogenous serotonin and are able to synthesize serotonin from L-tryptophan and to catabolize it by monoamine oxidase B. Moreover, the cells take up serotonin by a carrier-mediated mechanism very similar to that of serotoninergic neurons. The expression of the simian virus 40 oncogenes, which promoted immortalization, does not therefore prevent further differentiation. This inducible cell line constitutes a valuable model for cellular and molecular studies concerning the physiology and the pharmacological modulation of the serotoninergic phenotype. Images PMID:2155426

  20. The Mouse Olfactory Peduncle

    PubMed Central

    Brunjes, Peter C; Kay, Rachel B; Arrivillaga, J. P

    2012-01-01

    The olfactory peduncle, the region connecting the olfactory bulb with the basal forebrain, contains several neural areas that have received relatively little attention. The present work includes studies that provide an overview of the region in the mouse. An analysis of cell soma size in pars principalis (pP) of the anterior olfactory nucleus (AON) revealed considerable differences in tissue organization between mice and rats. An unbiased stereological study of neuron number in the cell-dense regions of pars externa (pE) and pP of the AON of 3, 12 and 24 month-old mice indicated that pE has about 16,500 cells in 0.043 mm3and pP about 58,300 cells in 0.307 mm3. Quantitative Golgi studies of pyramidal neurons in pP suggested that mouse neurons are similar though smaller to those of the rat. An immunohistochemical analysis demonstrated that all peduncular regions (pE, pP, the dorsal peduncular cortex, ventral tenia tecta, and anterior olfactory tubercle and piriform cortex) have cells that express either calbindin, calretinin, parvalbumin, somatostatin, vasoactive intestinal polypeptide, neuropeptide Y or cholecystokinin (antigens commonly co-expressed by subspecies of GABAergic neurons), though the relative numbers of each cell type differs between zones. Finally, an electron microscopic comparison of the organization of myelinated fibers in lateral olfactory tract in the anterior and posterior peduncle indicated that the region is less orderly in mice than in the rat. The results provide a caveat for investigators who generalize data between species as both similarities and differences between the laboratory mouse and rat were observed. PMID:21618219

  1. Preparation of superconductor precursor powders

    DOEpatents

    Bhattacharya, Raghunath

    1998-01-01

    A process for the preparation of a precursor metallic powder composition for use in the subsequent formation of a superconductor. The process comprises the steps of providing an electrodeposition bath comprising an electrolyte medium and a cathode substrate electrode, and providing to the bath one or more soluble salts of one or more respective metals which are capable of exhibiting superconductor properties upon subsequent appropriate treatment. The bath is continually energized to cause the metallic and/or reduced particles formed at the electrode to drop as a powder from the electrode into the bath, and this powder, which is a precursor powder for superconductor production, is recovered from the bath for subsequent treatment. The process permits direct inclusion of all metals in the preparation of the precursor powder, and yields an amorphous product mixed on an atomic scale to thereby impart inherent high reactivity. Superconductors which can be formed from the precursor powder include pellet and powder-in-tube products.

  2. Lysophosphatidic Acid Receptor Is a Functional Marker of Adult Hippocampal Precursor Cells

    PubMed Central

    Walker, Tara L.; Overall, Rupert W.; Vogler, Steffen; Sykes, Alex M.; Ruhwald, Susann; Lasse, Daniela; Ichwan, Muhammad; Fabel, Klaus; Kempermann, Gerd

    2016-01-01

    Summary Here, we show that the lysophosphatidic acid receptor 1 (LPA1) is expressed by a defined population of type 1 stem cells and type 2a precursor cells in the adult mouse dentate gyrus. LPA1, in contrast to Nestin, also marks the quiescent stem cell population. Combining LPA1-GFP with EGFR and prominin-1 expression, we have enabled the prospective separation of both proliferative and non-proliferative precursor cell populations. Transcriptional profiling of the isolated proliferative precursor cells suggested immune mechanisms and cytokine signaling as molecular regulators of adult hippocampal precursor cell proliferation. In addition to LPA1 being a marker of this important stem cell population, we also show that the corresponding ligand LPA is directly involved in the regulation of adult hippocampal precursor cell proliferation and neurogenesis, an effect that can be attributed to LPA signaling via the AKT and MAPK pathways. PMID:27050949

  3. Dynamic behaviors of the non-neural ectoderm during mammalian cranial neural tube closure.

    PubMed

    Ray, Heather J; Niswander, Lee A

    2016-08-15

    The embryonic brain and spinal cord initially form through the process of neural tube closure (NTC). NTC is thought to be highly similar between rodents and humans, and studies of mouse genetic mutants have greatly increased our understanding of the molecular basis of NTC with relevance for human neural tube defects. In addition, studies using amphibian and chick embryos have shed light into the cellular and tissue dynamics underlying NTC. However, the dynamics of mammalian NTC has been difficult to study due to in utero development until recently when advances in mouse embryo ex vivo culture techniques along with confocal microscopy have allowed for imaging of mouse NTC in real time. Here, we have performed live imaging of mouse embryos with a particular focus on the non-neural ectoderm (NNE). Previous studies in multiple model systems have found that the NNE is important for proper NTC, but little is known about the behavior of these cells during mammalian NTC. Here we utilized a NNE-specific genetic labeling system to assess NNE dynamics during murine NTC and identified different NNE cell behaviors as the cranial region undergoes NTC. These results bring valuable new insight into regional differences in cellular behavior during NTC that may be driven by different molecular regulators and which may underlie the various positional disruptions of NTC observed in humans with neural tube defects. PMID:27343896

  4. The responses of neural stem cells to the level of GSK-3 depend on the tissue of origin

    PubMed Central

    Holowacz, Tamara; Alexson, Tania O.; Coles, Brenda L.; Doble, Bradley W.; Kelly, Kevin F.; Woodgett, James R.; Van Der Kooy, Derek

    2013-01-01

    Summary Neural stem cells (NSCs) can be obtained from a variety of sources, but not all NSCs exhibit the same characteristics. We have examined how the level of glycogen synthase kinase-3 activity regulates NSCs obtained from different sources: the mouse embryonic striatum, embryonic hippocampus, and mouse ES cells. Growth of striatal NSCs is enhanced by mild inhibition of GSK-3 but not by strong inhibition that is accompanied by Wnt/TCF transcriptional activation. In contrast, the growth of hippocampal NSCs is enhanced by both mild inhibition of GSK-3 as well as stronger inhibition. Active Wnt/TCF signaling, which occurs normally in the embryonic hippocampus, is required for growth of neural stem and progenitor cells. In the embryonic striatal germinal zone, however, TCF signaling is normally absent and its activation inhibits growth of NSCs from this region. Using a genetic model for progressive loss of GSK-3, we find that primitive ES cell-derived NSCs resemble striatal NSCs. That is, partial loss of GSK-3 alleles leads to an increase in NSCs while complete ablation of GSK-3, and activation of TCF-signaling, leads to their decline. Furthermore, expression of dominant negative TCF-4 in the GSK-3-null background was effective in blocking expression of Wnt-response genes and was also able to rescue neuronal gene expression. These results reveal that GSK-3 regulates NSCs by divergent pathways depending on the tissue of origin. The responses of these neural precursor cells may be contingent on baseline Wnt/TCF signaling occurring in a particular tissue. PMID:23951407

  5. Neural Engineering

    NASA Astrophysics Data System (ADS)

    He, Bin

    About the Series: Bioelectric Engineering presents state-of-the-art discussions on modern biomedical engineering with respect to applications of electrical engineering and information technology in biomedicine. This focus affirms Springer's commitment to publishing important reviews of the broadest interest to biomedical engineers, bioengineers, and their colleagues in affiliated disciplines. Recent volumes have covered modeling and imaging of bioelectric activity, neural engineering, biosignal processing, bionanotechnology, among other topics.

  6. Age and gene overexpression interact to abolish nesting behavior in Tg2576 amyloid precursor protein (APP) mice.

    PubMed

    Wesson, Daniel W; Wilson, Donald A

    2011-01-01

    Elucidating the modulators of social behavioral is important in understanding the neural basis of behavior and in developing methods to enhance behavior in cases of disorder. The work here stems from the observation that the Alzheimer's disease mouse model Tg2576, overexpressing human mutations of the amyloid-β precursor protein (APP), fails to construct nests when supplied paper towels in their home cages. Experiments using commercially available cotton nesting material found similar results. Additional experiments revealed that the genotype effect is progressively modulated by age in APP mice but not their WT counterparts. There was no effect of sex on nesting behavior in any group. Finally, this effect was independent of ambient temperature - even when subjected to a cold environment, APP mice fail to build nests whereas WT mice do. These results suggest that the APP gene plays a role in affiliative behaviors and are discussed in relation to disorders characteristic of mutations in the APP gene and in affective dysfunction, including Alzheimer's disease. PMID:20804789

  7. Expression of planar cell polarity genes during development of the mouse CNS.

    PubMed

    Tissir, Fadel; Goffinet, André M

    2006-02-01

    Atypical cadherin (Celsr3) and the receptor Frizzled3 (Fzd3) are crucial for the development of axonal tracts in the mouse CNS. Celsr3 and Fzd3 are orthologues of the Drosophila'planar cell polarity' (PCP) genes flamingo/starry night (fmi/stan) and frizzled, respectively. Reasoning that Celsr3 and Fzd3 might interact with PCP orthologues in mammals like they do in flies, we used mRNA in situ hybridization to compare the expression of Celsr3 and Fzd3 with that of dishevelled 1, 2 and 3 (Dvl1-3), van gogh-like 1 and 2 (Vangl1, 2), and prickle-like 1 and 2 (Prickle1, 2), during mouse CNS development, from embryonic day 10.5 to postnatal day 21. With the relative exception of Vangl1, all genes were expressed in the developing CNS. Although Celsr3- and Fzd3-deficient mice have similar phenotypes, Fzd3 expression was more widespread than that of Celsr3. Vangl2 and Dvl2 were preferentially expressed in ventricular zones, in keeping with their role during neural tube closure, where they could be partners of Celsr1. Dvl1 had a broad expression, reminiscent of that of Celsr2, and may be involved in neural maintenance. A large overlap in the expression territories of Dvl genes suggested redundancy. Vangl1 and Prickle1 had expression canvases different from each other and from other candidates, indicating unrelated function. Like Celsr3, Dvl3 and Prickle2 were expressed more strongly in postmitotic neurons than in precursors. Thus, the analogy between the PCP and Celsr3-Fzd3 genetic networks is limited, but may include Dvl3 and/or Prickle2. PMID:16487141

  8. Binding of a specific ligand inhibits import of a purified precursor protein into mitochondria

    NASA Astrophysics Data System (ADS)

    Eilers, Martin; Schatz, Gottfried

    1986-07-01

    Methotrexate, a folate antagonist, blocks import into mitochondria of mouse dihydrofolate reductase fused to a mitochondrial presequence. Methotrexate does not mask the presequence, but stabilizes the dihydrofolate reductase moiety. It does not inhibit import of the authentic precursor from which the presequence is derived. This suggests that dihydrofolate reductase must at least partly unfold in order to be transported across mitochondrial membranes.

  9. Cardiovascular Development and the Colonizing Cardiac Neural Crest Lineage

    PubMed Central

    Snider, Paige; Olaopa, Michael; Firulli, Anthony B.

    2008-01-01

    Although it is well established that transgenic manipulation of mammalian neural crest-related gene expression and microsurgical removal of premigratory chicken and Xenopus embryonic cardiac neural crest progenitors results in a wide spectrum of both structural and functional congenital heart defects, the actual functional mechanism of the cardiac neural crest cells within the heart is poorly understood. Neural crest cell migration and appropriate colonization of the pharyngeal arches and outflow tract septum is thought to be highly dependent on genes that regulate cell-autonomous polarized movement (i.e., gap junctions, cadherins, and noncanonical Wnt1 pathway regulators). Once the migratory cardiac neural crest subpopulation finally reaches the heart, they have traditionally been thought to participate in septation of the common outflow tract into separate aortic and pulmonary arteries. However, several studies have suggested these colonizing neural crest cells may also play additional unexpected roles during cardiovascular development and may even contribute to a crest-derived stem cell population. Studies in both mice and chick suggest they can also enter the heart from the venous inflow as well as the usual arterial outflow region, and may contribute to the adult semilunar and atrioventricular valves as well as part of the cardiac conduction system. Furthermore, although they are not usually thought to give rise to the cardiomyocyte lineage, neural crest cells in the zebrafish (Danio rerio) can contribute to the myocardium and may have different functions in a species-dependent context. Intriguingly, both ablation of chick and Xenopus premigratory neural crest cells, and a transgenic deletion of mouse neural crest cell migration or disruption of the normal mammalian neural crest gene expression profiles, disrupts ventral myocardial function and/or cardiomyocyte proliferation. Combined, this suggests that either the cardiac neural crest secrete factor/s that

  10. Characterization of the Murine Myeloid Precursor Cell Line MuMac-E8

    PubMed Central

    Fricke, Stephan; Riemschneider, Sina; Kohlschmidt, Janine; Hilger, Nadja; Fueldner, Christiane; Knauer, Jens; Sack, Ulrich; Emmrich, Frank; Lehmann, Jörg

    2014-01-01

    Starting point for the present work was the assumption that the cell line MuMac-E8 represents a murine cell population with stem cell properties. Preliminary studies already pointed to the expression of stem-cell associated markers and a self-regenerative potential of the cells. The cell line MuMac-E8 should be examined for their differential stage within stem cell hierarchy. MuMac-E8 cells were derived from a chimeric mouse model of arthritis. It could be shown that MuMac-E8 cells express mRNA of some genes associated with pluripotent stem cells (Nanog, Nucleostemin), of genes for hematopoietic markers (EPCR, Sca-1, CD11b, CD45), for the mesenchymal marker CD105 and of genes for the neural markers Pax-6 and Ezrin. In methylcellulose and May-Grünwald-Giemsa staining, hematopoietic colonies were obtained but the hematopoietic system of lethally irradiated mice could not be rescued. Osteogenic differentiation was not detectable. Thus, it became evident that MuMac-E8 represents not a stem cell line. However, MuMac-E8 cells expressed several myeloid surface markers (i.e. CD11b, F4/80, CD14, CD64), showed phagocytosis and is capable of producing nitric oxide. Thus, this cell line seems to be arrested an advanced stage of myeloid differentiation. Adherence data measured by impedance-based real-time cell analysis together with cell morphology data suggested that MuMac-E8 represents a new macrophage precursor cell line exhibiting weak adherence. This cell line is suitable as an in-vitro model for testing of macrophage functions. Moreover, it might be also useful for differentiation or reprogramming studies. PMID:25546418

  11. Precursors of Hypertension: A Review

    PubMed Central

    Thomas, John; Neser, William B.; Thomas, Johniene; Semenya, Kofi; Green, Donald R.

    1983-01-01

    Recent advances in hypertension therapy have been remarkable; however, much less is known about those precursors that facilitate preventive and early intervention measures. This review of the literature indicates that relevant precursors are early elevated casual systolic blood pressures, positive family history, and obesity in females. Additional predisposing or enhancing factors point to high sodium ingestion, heavy smoking, and high socioecologic stress. Evidence for a high-risk hypertensive personality is not conclusive. There is a paucity of longitudinal data on hypertension in the black population. PMID:6864814

  12. Neural crest and placode interaction during the development of the cranial sensory system.

    PubMed

    Steventon, Ben; Mayor, Roberto; Streit, Andrea

    2014-05-01

    In the vertebrate head, the peripheral components of the sensory nervous system are derived from two embryonic cell populations, the neural crest and cranial sensory placodes. Both arise in close proximity to each other at the border of the neural plate: neural crest precursors abut the future central nervous system, while placodes originate in a common preplacodal region slightly more lateral. During head morphogenesis, complex events organise these precursors into functional sensory structures, raising the question of how their development is coordinated. Here we review the evidence that neural crest and placode cells remain in close proximity throughout their development and interact repeatedly in a reciprocal manner. We also review recent controversies about the relative contribution of the neural crest and placodes to the otic and olfactory systems. We propose that a sequence of mutual interactions between the neural crest and placodes drives the coordinated morphogenesis that generates functional sensory systems within the head. PMID:24491819

  13. The Expression and Function of the Achaete-Scute Genes in Tribolium castaneum Reveals Conservation and Variation in Neural Pattern Formation and Cell Fate Specification

    NASA Technical Reports Server (NTRS)

    Wheeler, Scott R.; Carrico, Michelle L.; Wilson, Beth A.; Brown, Susan J.; Skeath, James B.

    2003-01-01

    SUMMARY The study of achaete-scute (ac/sc) genes has recently become a paradigm to understand the evolution and development of the arthropod nervous system. We describe the identification and characterization of the ache genes in the coleopteran insect species Tribolium castaneum. We have identified two Tribolium ache genes - achaete-scute homolog (Tc-ASH) a proneural gene and asense (Tc-ase) a neural precursor gene that reside in a gene complex. Focusing on the embryonic central nervous system we fmd that Tc-ASH is expressed in all neural precursors and the proneural clusters from which they segregate. Through RNAi and misexpression studies we show that Tc-ASH is necessary for neural precursor formation in Triboliurn and sufficient for neural precursor formation in Drosophila. Comparison of the function of the Drosophila and Triboliurn proneural ac/sc genes suggests that in the Drosophila lineage these genes have maintained their ancestral function in neural precursor formation and have acquired a new role in the fate specification of individual neural precursors. Furthermore, we find that Tc-use is expressed in all neural precursors suggesting an important and conserved role for asense genes in insect nervous system development. Our analysis of the Triboliurn ache genes indicates significant plasticity in gene number, expression and function, and implicates these modifications in the evolution of arthropod neural development.

  14. The expression and function of the achaete-scute genes in Tribolium castaneum reveals conservation and variation in neural pattern formation and cell fate specification

    NASA Technical Reports Server (NTRS)

    Wheeler, Scott R.; Carrico, Michelle L.; Wilson, Beth A.; Brown, Susan J.; Skeath, James B.

    2003-01-01

    The study of achaete-scute (ac/sc) genes has recently become a paradigm to understand the evolution and development of the arthropod nervous system. We describe the identification and characterization of the ac/sc genes in the coleopteran insect species Tribolium castaneum. We have identified two Tribolium ac/sc genes - achaete-scute homolog (Tc-ASH) a proneural gene and asense (Tc-ase) a neural precursor gene that reside in a gene complex. Focusing on the embryonic central nervous system we find that Tc-ASH is expressed in all neural precursors and the proneural clusters from which they segregate. Through RNAi and misexpression studies we show that Tc-ASH is necessary for neural precursor formation in Tribolium and sufficient for neural precursor formation in Drosophila. Comparison of the function of the Drosophila and Tribolium proneural ac/sc genes suggests that in the Drosophila lineage these genes have maintained their ancestral function in neural precursor formation and have acquired a new role in the fate specification of individual neural precursors. Furthermore, we find that Tc-ase is expressed in all neural precursors suggesting an important and conserved role for asense genes in insect nervous system development. Our analysis of the Tribolium ac/sc genes indicates significant plasticity in gene number, expression and function, and implicates these modifications in the evolution of arthropod neural development.

  15. PAX transcription factors in neural crest development.

    PubMed

    Monsoro-Burq, Anne H

    2015-08-01

    The nine vertebrate PAX transcription factors (PAX1-PAX9) play essential roles during early development and organogenesis. Pax genes were identified in vertebrates using their homology with the Drosophila melanogaster paired gene DNA-binding domain. PAX1-9 functions are largely conserved throughout vertebrate evolution, in particular during central nervous system and neural crest development. The neural crest is a vertebrate invention, which gives rise to numerous derivatives during organogenesis, including neurons and glia of the peripheral nervous system, craniofacial skeleton and mesenchyme, the heart outflow tract, endocrine and pigment cells. Human and mouse spontaneous mutations as well as experimental analyses have evidenced the critical and diverse functions of PAX factors during neural crest development. Recent studies have highlighted the role of PAX3 and PAX7 in neural crest induction. Additionally, several PAX proteins - PAX1, 3, 7, 9 - regulate cell proliferation, migration and determination in multiple neural crest-derived lineages, such as cardiac, sensory, and enteric neural crest, pigment cells, glia, craniofacial skeleton and teeth, or in organs developing in close relationship with the neural crest such as the thymus and parathyroids. The diverse PAX molecular functions during neural crest formation rely on fine-tuned modulations of their transcriptional transactivation properties. These modulations are generated by multiple means, such as different roles for the various isoforms (formed by alternative splicing), or posttranslational modifications which alter protein-DNA binding, or carefully orchestrated protein-protein interactions with various co-factors which control PAX proteins activity. Understanding these regulations is the key to decipher the versatile roles of PAX transcription factors in neural crest development, differentiation and disease. PMID:26410165

  16. Preparation of superconductor precursor powders

    DOEpatents

    Bhattacharya, R.

    1998-08-04

    A process for the preparation of a precursor metallic powder composition for use in the subsequent formation of a superconductor. The process comprises the steps of providing an electrodeposition bath comprising an electrolyte medium and a cathode substrate electrode, and providing to the bath one or more soluble salts of one or more respective metals which are capable of exhibiting superconductor properties upon subsequent appropriate treatment. The bath is continually energized to cause the metallic and/or reduced particles formed at the electrode to drop as a powder from the electrode into the bath, and this powder, which is a precursor powder for superconductor production, is recovered from the bath for subsequent treatment. The process permits direct inclusion of all metals in the preparation of the precursor powder, and yields an amorphous product mixed on an atomic scale to thereby impart inherent high reactivity. Superconductors which can be formed from the precursor powder include pellet and powder-in-tube products. 7 figs.

  17. Preparation of superconductor precursor powders

    DOEpatents

    Bhattacharya, Raghunath; Blaugher, Richard D.

    1995-01-01

    A process for the preparation of a precursor metallic powder composition for use in the subsequent formation of a superconductor. The process comprises the steps of providing an electrodeposition bath comprising an electrolyte medium and a cathode substrate electrode, and providing to the bath one or more soluble salts of one or more respective metals, such as nitrate salts of thallium, barium, calcium, and copper, which are capable of exhibiting superconductor properties upon subsequent appropriate treatment. The bath is continually energized to cause the metallic particles formed at the electrode to drop as a powder from the electrode into the bath, and this powder, which is a precursor powder for superconductor production, is recovered from the bath for subsequent treatment. The process permits direct inclusion of thallium in the preparation of the precursor powder, and yields an amorphous product mixed on an atomic scale to thereby impart inherent high reactivity. Superconductors which can be formed from the precursor powder include pellet and powder-in-tube products.

  18. Primitive neural stem cells from the mammalian epiblast differentiate to definitive neural stem cells under the control of Notch signaling.

    PubMed

    Hitoshi, Seiji; Seaberg, Raewyn M; Koscik, Cheryl; Alexson, Tania; Kusunoki, Susumu; Kanazawa, Ichiro; Tsuji, Shoji; van der Kooy, Derek

    2004-08-01

    Basic fibroblast growth factor (FGF2)-responsive definitive neural stem cells first appear in embryonic day 8.5 (E8.5) mouse embryos, but not in earlier embryos, although neural tissue exists at E7.5. Here, we demonstrate that leukemia inhibitory factor-dependent (but not FGF2-dependent) sphere-forming cells are present in the earlier (E5.5-E7.5) mouse embryo. The resultant clonal sphere cells possess self-renewal capacity and neural multipotentiality, cardinal features of the neural stem cell. However, they also retain some nonneural properties, suggesting that they are the in vivo cells' equivalent of the primitive neural stem cells that form in vitro from embryonic stem cells. The generation of the in vivo primitive neural stem cell was independent of Notch signaling, but the activation of the Notch pathway was important for the transition from the primitive to full definitive neural stem cell properties and for the maintenance of the definitive neural stem cell state. PMID:15289455

  19. Neural induction, neural fate stabilization, and neural stem cells.

    PubMed

    Moody, Sally A; Je, Hyun-Soo

    2002-04-28

    The promise of stem cell therapy is expected to greatly benefit the treatment of neurodegenerative diseases. An underlying biological reason for the progressive functional losses associated with these diseases is the extremely low natural rate of self-repair in the nervous system. Although the mature CNS harbors a limited number of self-renewing stem cells, these make a significant contribution to only a few areas of brain. Therefore, it is particularly important to understand how to manipulate embryonic stem cells and adult neural stem cells so their descendants can repopulate and functionally repair damaged brain regions. A large knowledge base has been gathered about the normal processes of neural development. The time has come for this information to be applied to the problems of obtaining sufficient, neurally committed stem cells for clinical use. In this article we review the process of neural induction, by which the embryonic ectodermal cells are directed to form the neural plate, and the process of neural-fate stabilization, by which neural plate cells expand in number and consolidate their neural fate. We will present the current knowledge of the transcription factors and signaling molecules that are known to be involved in these processes. We will discuss how these factors may be relevant to manipulating embryonic stem cells to express a neural fate and to produce large numbers of neurally committed, yet undifferentiated, stem cells for transplantation therapies. PMID:12805974

  20. Crucial Role of Rapgef2 and Rapgef6, a Family of Guanine Nucleotide Exchange Factors for Rap1 Small GTPase, in Formation of Apical Surface Adherens Junctions and Neural Progenitor Development in the Mouse Cerebral Cortex123

    PubMed Central

    Maeta, Kazuhiro; Edamatsu, Hironori; Nishihara, Kaori; Ikutomo, Junji; Bilasy, Shymaa E.

    2016-01-01

    Abstract Cerebral neocortex development in mammals requires highly orchestrated events involving proliferation, differentiation, and migration of neural progenitors and neurons. Rapgef2 and Rapgef6 constitute a unique family of guanine nucleotide exchange factors for Rap1 small GTPase, which is known to play crucial roles in migration of postmitotic neurons. We previously reported that conditional knockout of Rapgef2 in dorsal telencephalon (Rapgef2-cKO) resulted in the formation of an ectopic cortical mass (ECM) resembling that of subcortical band heterotopia. Here we show that double knockout of Rapgef6 in Rapgef2-cKO mice (Rapgef2/6-dKO) results in marked enlargement of the ECM. While Rapgef2-cKO affects late-born neurons only, Rapgef2/6-dKO affects both early-born and late-born neurons. The Rapgef2-cKO cortex at embryonic day (E) 15.5, and the Rapgef2/6-dKO cortex at E13.5 and E15.5 show disruption of the adherens junctions (AJs) on the apical surface, detachment of radial glial cells (RGCs) from the apical surface and disorganization of the radial glial fiber system, which are accompanied by aberrant distribution of RGCs and intermediate progenitors, normally located in the ventricular zone and the subventricular zone, respectively, over the entire cerebral cortex. Moreover, intrauterine transduction of Cre recombinase into the Rapgef2flox/flox brains also results in the apical surface AJ disruption and the RGC detachment from the apical surface, both of which are effectively suppressed by cotransduction of the constitutively active Rap1 mutant Rap1G12V. These results demonstrate a cell-autonomous role of the Rapgef2/6-Rap1 pathway in maintaining the apical surface AJ structures, which is necessary for the proper development of neural progenitor cells. PMID:27390776

  1. Three-dimensional bioprinting of rat embryonic neural cells.

    PubMed

    Lee, Wonhye; Pinckney, Jason; Lee, Vivian; Lee, Jong-Hwan; Fischer, Krisztina; Polio, Samuel; Park, Je-Kyun; Yoo, Seung-Schik

    2009-05-27

    We present a direct cell printing technique to pattern neural cells in a three-dimensional (3D) multilayered collagen gel. A layer of collagen precursor was printed to provide a scaffold for the cells, and the rat embryonic neurons and astrocytes were subsequently printed on the layer. A solution of sodium bicarbonate was applied to the cell containing collagen layer as nebulized aerosols, which allowed the gelation of the collagen. This process was repeated layer-by-layer to construct the 3D cell-hydrogel composites. Upon characterizing the relationship between printing resolutions and the growth of printed neural cells, single/multiple layers of neural cell-hydrogel composites were constructed and cultured. The on-demand capability to print neural cells in a multilayered hydrogel scaffold offers flexibility in generating artificial 3D neural tissue composites. PMID:19369905

  2. Auraptene induces oligodendrocyte lineage precursor cells in a cuprizone-induced animal model of demyelination.

    PubMed

    Nakajima, Mitsunari; Shimizu, Risei; Furuta, Kohei; Sugino, Mami; Watanabe, Takashi; Aoki, Rui; Okuyama, Satoshi; Furukawa, Yoshiko

    2016-05-15

    We investigated the effects of auraptene on mouse oligodendroglial cell lineage in an animal model of demyelination induced by cuprizone. Auraptene, a citrus coumarin, was intraperitoneally administered to mice fed the demyelinating agent cuprizone. Immunohistochemical analysis of the corpus callosum and/or Western blotting analysis of brain extracts revealed that cuprizone reduced immunoreactivity for myelin-basic protein, a marker of myelin, whereas it increased immunoreactivity to platelet derived-growth factor receptor-α, a marker of oligodendrocyte precursor cells. Administration of auraptene enhanced the immunoreactivity to oligodendrocyte transcription factor 2, a marker of oligodendrocyte precursor cells and oligodendrocyte lineage precursor cells, but had no effect on immunoreactivity to myelin-basic protein or platelet-derived growth factor receptor-α. These findings suggest that auraptene promotes the production of oligodendrocyte lineage precursor cells in an animal model of demyelination and may be useful for individuals with demyelinating diseases. PMID:26944297

  3. Differential activation of Myf5 and MyoD by different Wnts in explants of mouse paraxial mesoderm and the later activation of myogenesis in the absence of Myf5.

    PubMed

    Tajbakhsh, S; Borello, U; Vivarelli, E; Kelly, R; Papkoff, J; Duprez, D; Buckingham, M; Cossu, G

    1998-11-01

    Activation of myogenesis in newly formed somites is dependent upon signals derived from neighboring tissues, namely axial structures (neural tube and notochord) and dorsal ectoderm. In explants of paraxial mesoderm from mouse embryos, axial structures preferentially activate myogenesis through a Myf5-dependent pathway and dorsal ectoderm preferentially through a MyoD-dependent pathway. Here we report that cells expressing Wnt1 will preferentially activate Myf5 while cells expressing Wnt7a will preferentially activate MyoD. Wnt1 is expressed in the dorsal neural tube and Wnt7a in dorsal ectoderm in the early embryo, therefore both can potentially act in vivo to activate Myf5 and MyoD, respectively. Wnt4, Wnt5a and Wnt6 exert an intermediate effect activating both Myf5 and MyoD equivalently in paraxial mesoderm. Sonic Hedgehog synergises with both Wnt1 and Wnt7a in explants from E8.5 paraxial mesoderm but not in explants from E9.5 embryos. Signaling through different myogenic pathways may explain the rescue of muscle formation in Myf5 null embryos, which do not form an early myotome but later develop both epaxial and hypaxial musculature. Explants of unsegmented paraxial mesoderm contain myogenic precursors capable of expressing MyoD in response to signaling from a neural tube isolated from E10.5 embryos, the developmental stage when MyoD is present throughout the embryo. Myogenic cells cannot activate MyoD in response to signaling from a less mature neural tube. Together these data suggest that different Wnt molecules can activate myogenesis through different pathways such that commitment of myogenic precursors is precisely regulated in space and time to achieve the correct pattern of skeletal muscle development. PMID:9753670

  4. Independent Optical Excitation of Distinct Neural Populations

    PubMed Central

    Klapoetke, Nathan C; Murata, Yasunobu; Kim, Sung Soo; Pulver, Stefan R.; Birdsey-Benson, Amanda; Cho, Yong Ku; Morimoto, Tania K; Chuong, Amy S; Carpenter, Eric J; Tian, Zhijian; Wang, Jun; Xie, Yinlong; Yan, Zhixiang; Zhang, Yong; Chow, Brian Y; Surek, Barbara; Melkonian, Michael; Jayaraman, Vivek; Constantine-Paton, Martha; Wong, Gane Ka-Shu; Boyden, Edward S

    2014-01-01

    Optogenetic tools enable the causal examination of how specific cell types contribute to brain circuit functions. A long-standing question is whether it is possible to independently activate two distinct neural populations in mammalian brain tissue. Such a capability would enable the examination of how different synapses or pathways interact to support computation. Here we report two new channelrhodopsins, Chronos and Chrimson, obtained through the de novo sequencing and physiological characterization of opsins from over 100 species of algae. Chrimson is 45 nm red-shifted relative to any previous channelrhodopsin, important for scenarios where red light would be preferred; we show minimal visual system mediated behavioral artifact in optogenetically stimulated Drosophila. Chronos has faster kinetics than any previous channelrhodopsin, yet is effectively more light-sensitive. Together, these two reagents enable crosstalk-free two-color activation of neural spiking and downstream synaptic transmission in independent neural populations in mouse brain slice. PMID:24509633

  5. Functional Analysis of Various Promoters in Lentiviral Vectors at Different Stages of In Vitro Differentiation of Mouse Embryonic Stem Cells

    PubMed Central

    Hong, Sunghoi; Hwang, Dong-Youn; Yoon, Soonsang; Isacson, Ole; Ramezani, Ali; Hawley, Robert G

    2008-01-01

    Given the therapeutic potential offered by embryonic stem (ES) cells, it is critical to optimize stable gene delivery and expression at different developmental stages of ES cell differentiation. Here, we systematically analyzed lentiviral vectors containing the following promoters: the human elongation factor 1α (EF1α) promoter, the human cytomegalovirus (CMV) immediate early region enhancer-promoter, the composite CAG promoter (consisting of the CMV immediate early enhancer and the chicken β-actin promoter), the human phosphoglycerate kinase 1 (PGK) promoter, the murine stem cell virus (MSCV) long terminal repeat (LTR), or the gibbon ape leukemia virus (GALV) LTR. Our results show that the EF1α promoter directed robust transgene expression at every stage of mouse ES cell differentiation, whereas the CMV promoter drove transgene expression only during late stages. Similarly, the CAG and PGK promoters drove transgene expression at a significant level only during late stages. The MSCV LTR and the GALV LTR exhibited much lower promoter activities at all stages. Interestingly, mouse ES cells transduced with the EF1α promoter-containing lentiviral vector lost most of their transgene expression during in vitro differentiation to neural precursors and neuronal cells. Our results demonstrate that different cellular and viral promoters exhibit very distinct and dynamic properties not only in terms of promoter strength but also with respect to differentiation stage-specific activity. PMID:17609656

  6. Electronic Neural Networks

    NASA Technical Reports Server (NTRS)

    Thakoor, Anil

    1990-01-01

    Viewgraphs on electronic neural networks for space station are presented. Topics covered include: electronic neural networks; electronic implementations; VLSI/thin film hybrid hardware for neurocomputing; computations with analog parallel processing; features of neuroprocessors; applications of neuroprocessors; neural network hardware for terrain trafficability determination; a dedicated processor for path planning; neural network system interface; neural network for robotic control; error backpropagation algorithm for learning; resource allocation matrix; global optimization neuroprocessor; and electrically programmable read only thin-film synaptic array.

  7. Cell polarity pathways converge and extend to regulate neural tube closure.

    PubMed

    Zohn, Irene E; Chesnutt, Catherine R; Niswander, Lee

    2003-09-01

    Neural tube defects, such as spinabifida, craniorachischisis and anencephaly, are some of the most common birth defects in humans. Recent studies in mouse model systems suggest that craniorachischisis is associated with mutations in genes that regulate cell polarity. Using Xenopus as a model system, Wallingford and Harland have now shed light on the mechanism by which these pathways affect neural tube closure. PMID:12946622

  8. Comparative analysis of neural crest cell death, migration, and function during vertebrate embryogenesis.

    PubMed

    Kulesa, Paul; Ellies, Debra L; Trainor, Paul A

    2004-01-01

    Cranial neural crest cells are a multipotent, migratory population that generates most of the cartilage, bone, connective tissue and peripheral nervous system in the vertebrate head. Proper neural crest cell patterning is essential for normal craniofacial morphogenesis and is highly conserved among vertebrates. Neural crest cell patterning is intimately connected to the early segmentation of the neural tube, such that neural crest cells migrate in discrete segregated streams. Recent advances in live embryo imaging have begun to reveal the complex behaviour of neural crest cells which involve intricate cell-cell and cell-environment interactions. Despite the overall similarity in neural crest cell migration between distinct vertebrates species there are important mechanistic differences. Apoptosis for example, is important for neural crest cell patterning in chick embryos but not in mouse, frog or fish embryos. In this paper we highlight the potential evolutionary significance of such interspecies differences in jaw development and evolution. Developmental Dynamics 229:14-29, 2004. PMID:14699574

  9. Notch Signaling Maintains Neural Rosette Polarity

    PubMed Central

    Main, Heather; Radenkovic, Jelena; Jin, Shao-bo; Lendahl, Urban; Andersson, Emma R.

    2013-01-01

    Formation of the metazoan body plan requires a complex interplay of morphological changes and patterning, and central to these processes is the establishment of apical/basal cell polarity. In the developing nervous system, apical/basal cell polarity is essential for neural tube closure and maintenance of the neural stem cell population. In this report we explore how a signaling pathway important for nervous system development, Notch signaling, impacts on apical/basal cell polarity in neural differentiation. CSL−/− mouse embryos, which are devoid of canonical Notch signaling, demonstrated a neural tube phenotype consistent with cell polarity and convergent extension defects, including deficiencies in the restricted expression of apical polarity markers in the neuroepithelium. CSL−/− mouse embryonic stem (ES) cells, cultured at low density, behaved as wild-type in the establishment of neural progenitors and apical specification, though progression through rosette formation, an in vitro correlate of neurulation, required CSL for correct maintenance of rosette structure and regulation of neuronal differentiation. Similarly, acute pharmacological inhibition of Notch signaling led to the breakdown of neural rosettes and accelerated neuronal differentiation. In addition to functional Notch signaling, rosette integrity was found to require actin polymerization and Rho kinase (ROCK) activity. Disruption of rosettes through inhibition of actin polymerization or ROCK activity, however, had no effect on neuronal differentiation, indicating that rosette maintenance is not a prerequisite for normal neuronal differentiation. In conclusion, our data indicate that Notch signaling plays a role not only in differentiation, but also in organization and maintenance of polarity during development of the early nervous system. PMID:23675446

  10. The Innate Lymphoid Cell Precursor.

    PubMed

    Ishizuka, Isabel E; Constantinides, Michael G; Gudjonson, Herman; Bendelac, Albert

    2016-05-20

    The discovery of tissue-resident innate lymphoid cell populations effecting different forms of type 1, 2, and 3 immunity; tissue repair; and immune regulation has transformed our understanding of mucosal immunity and allergy. The emerging complexity of these populations along with compounding issues of redundancy and plasticity raise intriguing questions about their precise lineage relationship. Here we review advances in mapping the emergence of these lineages from early lymphoid precursors. We discuss the identification of a common innate lymphoid cell precursor characterized by transient expression of the transcription factor PLZF, and the lineage relationships of innate lymphoid cells with conventional natural killer cells and lymphoid tissue inducer cells. We also review the rapidly growing understanding of the network of transcription factors that direct the development of these lineages. PMID:27168240

  11. Precursor polymer compositions comprising polybenzimidazole

    SciTech Connect

    Klaehn, John R.; Peterson, Eric S.; Orme, Christopher J.

    2015-07-14

    Stable, high performance polymer compositions including polybenzimidazole (PBI) and a melamine-formaldehyde polymer, such as methylated, poly(melamine-co-formaldehyde), for forming structures such as films, fibers and bulky structures. The polymer compositions may be formed by combining polybenzimidazole with the melamine-formaldehyde polymer to form a precursor. The polybenzimidazole may be reacted and/or intertwined with the melamine-formaldehyde polymer to form the polymer composition. For example, a stable, free-standing film having a thickness of, for example, between about 5 .mu.m and about 30 .mu.m may be formed from the polymer composition. Such films may be used as gas separation membranes and may be submerged into water for extended periods without crazing and cracking. The polymer composition may also be used as a coating on substrates, such as metal and ceramics, or may be used for spinning fibers. Precursors for forming such polymer compositions are also disclosed.

  12. Spinal Cord Neuronal Precursors Generate Multiple Neuronal Phenotypes in Culture

    PubMed Central

    Kalyani, Anjali J.; Piper, David; Mujtaba, Tahmina; Lucero, Mary T.; Rao, Mahendra S.

    2010-01-01

    Neuronal restricted precursors (NRPs) (Mayer-Proschel et al., 1997) can generate multiple neurotransmitter phenotypes during maturation in culture. Undifferentiated E-NCAM+ (embryonic neural cell adhesion molecule) immunoreactive NRPs are mitotically active and electrically immature, and they express only a subset of neuronal markers. Fully mature cells are postmitotic, process-bearing cells that are neurofilament-M and synaptophysin immunoreactive, and they synthesize and respond to different subsets of neurotransmitter molecules. Mature neurons that synthesize and respond to glycine, glutamate, GABA, dopamine, and acetylcholine can be identified by immunocytochemistry, RT-PCR, and calcium imaging in mass cultures. Individual NRPs also generate heterogeneous progeny as assessed by neurotransmitter response and synthesis, demonstrating the multipotent nature of the precursor cells. Differentiation can be modulated by sonic hedgehog (Shh) and bone morphogenetic protein (BMP)-2/4 molecules. Shh acts as a mitogen and inhibits differentiation (including cholinergic differentiation). BMP-2 and BMP-4, in contrast, inhibit cell division and promote differentiation (including cholinergic differentiation). Thus, a single neuronal precursor cell can differentiate into multiple classes of neurons, and this differentiation can be modulated by environmental signals. PMID:9742154

  13. Nucleation precursors in protein crystallization

    PubMed Central

    Vekilov, Peter G.; Vorontsova, Maria A.

    2014-01-01

    Protein crystal nucleation is a central problem in biological crystallography and other areas of science, technology and medicine. Recent studies have demonstrated that protein crystal nuclei form within crucial precursors. Here, methods of detection and characterization of the precursors are reviewed: dynamic light scattering, atomic force microscopy and Brownian microscopy. Data for several proteins provided by these methods have demonstrated that the nucleation precursors are clusters consisting of protein-dense liquid, which are metastable with respect to the host protein solution. The clusters are several hundred nanometres in size, the cluster population occupies from 10−7 to 10−3 of the solution volume, and their properties in solutions supersaturated with respect to crystals are similar to those in homogeneous, i.e. undersaturated, solutions. The clusters exist owing to the conformation flexibility of the protein molecules, leading to exposure of hydrophobic surfaces and enhanced intermolecular binding. These results indicate that protein conformational flexibility might be the mechanism behind the metastable mesoscopic clusters and crystal nucleation. Investigations of the cluster properties are still in their infancy. Results on direct imaging of cluster behaviors and characterization of cluster mechanisms with a variety of proteins will soon lead to major breakthroughs in protein biophysics. PMID:24598910

  14. FoxA4 Favours Notochord Formation by Inhibiting Contiguous Mesodermal Fates and Restricts Anterior Neural Development in Xenopus Embryos

    PubMed Central

    Murgan, Sabrina; Castro Colabianchi, Aitana Manuela; Monti, Renato José; Boyadjián López, Laura Elena; Aguirre, Cecilia E.; Stivala, Ernesto González; López, Silvia L.

    2014-01-01

    In vertebrates, the embryonic dorsal midline is a crucial signalling centre that patterns the surrounding tissues during development. Members of the FoxA subfamily of transcription factors are expressed in the structures that compose this centre. Foxa2 is essential for dorsal midline development in mammals, since knock-out mouse embryos lack a definitive node, notochord and floor plate. The related gene foxA4 is only present in amphibians. Expression begins in the blastula –chordin and –noggin expressing centre (BCNE) and is later restricted to the dorsal midline derivatives of the Spemann's organiser. It was suggested that the early functions of mammalian foxa2 are carried out by foxA4 in frogs, but functional experiments were needed to test this hypothesis. Here, we show that some important dorsal midline functions of mammalian foxa2 are exerted by foxA4 in Xenopus. We provide new evidence that the latter prevents the respecification of dorsal midline precursors towards contiguous fates, inhibiting prechordal and paraxial mesoderm development in favour of the notochord. In addition, we show that foxA4 is required for the correct regionalisation and maintenance of the central nervous system. FoxA4 participates in constraining the prospective rostral forebrain territory during neural specification and is necessary for the correct segregation of the most anterior ectodermal derivatives, such as the cement gland and the pituitary anlagen. Moreover, the early expression of foxA4 in the BCNE (which contains precursors of the whole forebrain and most of the midbrain and hindbrain) is directly required to restrict anterior neural development. PMID:25343614

  15. Synaptogenesis: Modulation by Availability of Membrane Phospholipid Precursors.

    PubMed

    Cansev, Mehmet

    2016-09-01

    Phospholipids are the main constituents of brain membranes. Formation of new membranes requires that uridine, the omega-3 polyunsaturated fatty acids such as docosahexaenoic acid (DHA), and choline, the three circulating precursors of major phospholipids, interact via the Kennedy pathway. Supplementation of laboratory rodents with uridine, DHA and choline enhances the amount of brain membranes as well as synaptic proteins and increases the number of dendritic spines, the essential cytological precursor of new synapses. Hence, the newly formed membranes are utilized for synaptogenesis which underlies increased synaptic functioning evidenced by enhanced neurotransmission and cognition. In addition, this supplementation ameliorates the degeneration in a rat model of Parkinson's disease and mouse models of Alzheimer's disease (AD) when used in combination with several vitamins and cofactors. Hence, accumulating evidence shows that increasing the availability of phospholipid precursors, vitamins and cofactors to the brain through dietary supplementation enhances the formation of new synapses and provides protection under neurodegenerative conditions. The combination has been tested in clinical trials and a medication has been marketed for early-stage AD patients. PMID:27250850

  16. FoxP1 marks medium spiny neurons from precursors to maturity and is required for their differentiation.

    PubMed

    Precious, S V; Kelly, C M; Reddington, A E; Vinh, N N; Stickland, R C; Pekarik, V; Scherf, C; Jeyasingham, R; Glasbey, J; Holeiter, M; Jones, L; Taylor, M V; Rosser, A E

    2016-08-01

    Identifying the steps involved in striatal development is important both for understanding the striatum in health and disease, and for generating protocols to differentiate striatal neurons for regenerative medicine. The most prominent neuronal subtype in the adult striatum is the medium spiny projection neuron (MSN), which constitutes more than 85% of all striatal neurons and classically expresses DARPP-32. Through a microarray study of genes expressed in the whole ganglionic eminence (WGE: the developing striatum) in the mouse, we identified the gene encoding the transcription factor Forkhead box protein P1 (FoxP1) as the most highly up-regulated gene, thus providing unbiased evidence for the association of FoxP1 with MSN development. We also describe the expression of FoxP1 in the human fetal brain over equivalent gestational stages. FoxP1 expression persisted through into adulthood in the mouse brain, where it co-localised with all striatal DARPP-32 positive projection neurons and a small population of DARPP-32 negative cells. There was no co-localisation of FoxP1 with any interneuron markers. FoxP1 was detectable in primary fetal striatal cells following dissection, culture, and transplantation into the adult lesioned striatum, demonstrating its utility as an MSN marker for transplantation studies. Furthermore, DARPP-32 expression was absent from FoxP1 knock-out mouse WGE differentiated in vitro, suggesting that FoxP1 is important for the development of DARPP-32-positive MSNs. In summary, we show that FoxP1 labels MSN precursors prior to the expression of DARPP-32 during normal development, and in addition suggest that FoxP1 labels a sub-population of MSNs that are not co-labelled by DARPP-32. We demonstrate the utility of FoxP1 to label MSNs in vitro and following neural transplantation, and show that FoxP1 is required for DARPP-32 positive MSN differentiation in vitro. PMID:27154297

  17. A mutation in the Srrm4 gene causes alternative splicing defects and deafness in the Bronx waltzer mouse.

    PubMed

    Nakano, Yoko; Jahan, Israt; Bonde, Gregory; Sun, Xingshen; Hildebrand, Michael S; Engelhardt, John F; Smith, Richard J H; Cornell, Robert A; Fritzsch, Bernd; Bánfi, Botond

    2012-01-01

    Sensory hair cells are essential for hearing and balance. Their development from epithelial precursors has been extensively characterized with respect to transcriptional regulation, but not in terms of posttranscriptional influences. Here we report on the identification and functional characterization of an alternative-splicing regulator whose inactivation is responsible for defective hair-cell development, deafness, and impaired balance in the spontaneous mutant Bronx waltzer (bv) mouse. We used positional cloning and transgenic rescue to locate the bv mutation to the splicing factor-encoding gene Ser/Arg repetitive matrix 4 (Srrm4). Transcriptome-wide analysis of pre-mRNA splicing in the sensory patches of embryonic inner ears revealed that specific alternative exons were skipped at abnormally high rates in the bv mice. Minigene experiments in a heterologous expression system confirmed that these skipped exons require Srrm4 for inclusion into the mature mRNA. Sequence analysis and mutagenesis experiments showed that the affected transcripts share a novel motif that is necessary for the Srrm4-dependent alternative splicing. Functional annotations and protein-protein interaction data indicated that the encoded proteins cluster in the secretion and neurotransmission pathways. In addition, the splicing of a few transcriptional regulators was found to be Srrm4 dependent, and several of the genes known to be targeted by these regulators were expressed at reduced levels in the bv mice. Although Srrm4 expression was detected in neural tissues as well as hair cells, analyses of the bv mouse cerebellum and neocortex failed to detect splicing defects. Our data suggest that Srrm4 function is critical in the hearing and balance organs, but not in all neural tissues. Srrm4 is the first alternative-splicing regulator to be associated with hearing, and the analysis of bv mice provides exon-level insights into hair-cell development. PMID:23055939

  18. Complete nucleotide sequence of the human corticotropin-beta-lipotropin precursor gene.

    PubMed Central

    Takahashi, H; Hakamata, Y; Watanabe, Y; Kikuno, R; Miyata, T; Numa, S

    1983-01-01

    The nucleotide sequence of an 8658-base-pair human genomic DNA segment containing the entire corticotropin-beta-lipotropin precursor gene has been determined, and some sequence features of the gene and its flanking regions have been analysed. The gene is composed of 7665 base pairs including two introns of 3708 and 2886 base pairs. Comparison of the 5'-flanking sequences of the human, bovine and mouse corticotropin-beta-lipotropin precursor genes reveals the presence of a highly conserved region, which contains sequences of 14-15 base pairs homologous with sequences located upstream of the mRNA start site of other glucocorticoid-regulated genes. PMID:6314261

  19. Precursors of Short Gamma-Ray Bursts

    NASA Technical Reports Server (NTRS)

    Troja, E.; Rosswog, S.; Gehrels, N.

    2010-01-01

    We carried out a systematic search of precursors on the sample of short GRBs observed by Swift. We found that approx. 8-10% of short GRBs display such early episode of emission. One burst (GRB 090510) shows two precursor events, the former approx.13 s and the latter approx. 0.5 s before the GRB. We did not find any substantial difference between the precursor and the main GRB emission, and between short GRBs with and without precursors. We discuss possible mechanisms to reproduce the observed precursor emission within the scenario of compact object mergers. The implications of our results on quantum gravity constraints are also discussed.

  20. BMP receptor IA is required in mammalian neural crest cells for development of the cardiac outflow tract and ventricular myocardium

    PubMed Central

    Stottmann, Rolf W.; Choi, Murim; Mishina, Yuji; Meyers, Erik N.; Klingensmith, John

    2010-01-01

    Summary The neural crest is a multipotent, migratory cell population arising from the border of the neural and surface ectoderm. In mouse, the initial migratory neural crest cells occur at the five-somite stage. Bone morphogenetic proteins (BMPs), particularly BMP2 and BMP4, have been implicated as regulators of neural crest cell induction, maintenance, migration, differentiation and survival. Mouse has three known BMP2/4 type I receptors, of which Bmpr1a is expressed in the neural tube sufficiently early to be involved in neural crest development from the outset; however, earlier roles in other domains obscure its requirement in the neural crest. We have ablated Bmpr1a specifically in the neural crest, beginning at the five-somite stage. We find that most aspects of neural crest development occur normally; suggesting that BMPRIA is unnecessary for many aspects of early neural crest biology. However, mutant embryos display a shortened cardiac outflow tract with defective septation, a process known to require neural crest cells and to be essential for perinatal viability. Surprisingly, these embryos die in mid-gestation from acute heart failure, with reduced proliferation of ventricular myocardium. The myocardial defect may involve reduced BMP signaling in a novel, minor population of neural crest derivatives in the epicardium, a known source of ventricular myocardial proliferation signals. These results demonstrate that BMP2/4 signaling in mammalian neural crest derivatives is essential for outflow tract development and may regulate a crucial proliferation signal for the ventricular myocardium. PMID:15073157

  1. FGF signaling transforms non-neural ectoderm into neural crest.

    PubMed

    Yardley, Nathan; García-Castro, Martín I

    2012-12-15

    The neural crest arises at the border between the neural plate and the adjacent non-neural ectoderm. It has been suggested that both neural and non-neural ectoderm can contribute to the neural crest. Several studies have examined the molecular mechanisms that regulate neural crest induction in neuralized tissues or the neural plate border. Here, using the chick as a model system, we address the molecular mechanisms by which non-neural ectoderm generates neural crest. We report that in response to FGF the non-neural ectoderm can ectopically express several early neural crest markers (Pax7, Msx1, Dlx5, Sox9, FoxD3, Snail2, and Sox10). Importantly this response to FGF signaling can occur without inducing ectopic mesodermal tissues. Furthermore, the non-neural ectoderm responds to FGF by expressing the prospective neural marker Sox3, but it does not express definitive markers of neural or anterior neural (Sox2 and Otx2) tissues. These results suggest that the non-neural ectoderm can launch the neural crest program in the absence of mesoderm, without acquiring definitive neural character. Finally, we report that prior to the upregulation of these neural crest markers, the non-neural ectoderm upregulates both BMP and Wnt molecules in response to FGF. Our results provide the first effort to understand the molecular events leading to neural crest development via the non-neural ectoderm in amniotes and present a distinct response to FGF signaling. PMID:23000357

  2. Polymer precursors for ceramic composites

    NASA Technical Reports Server (NTRS)

    Hurwitz, Frances I.

    1986-01-01

    The fiber composite approach to reinforced ceramics provides the possibility of achieving ceramics with high fracture toughness relative to monolithics. Fabrication of ceramic composites, however, demands low processing temperatures to avoid fiber degradation. Formation of complex shapes further requires small diameter fibers as well as techniques for infiltrating the matrix between fibers. Polymers offer low temperature processability, control of rheology not available with ceramic powders, and should serve as precursors to matrix fibers. In recent years, a number of polysilanes and polysilezanes were investigated as potential presursors. A review of candidate polymers is presented, including recent studies of silsesquioxanes.

  3. A case of mistaken identity: CD11c-eYFP(+) cells in the normal mouse brain parenchyma and neural retina display the phenotype of microglia, not dendritic cells.

    PubMed

    Dando, Samantha J; Naranjo Golborne, Cecilia; Chinnery, Holly R; Ruitenberg, Marc J; McMenamin, Paul G

    2016-08-01

    Under steady-state conditions the central nervous system (CNS) is traditionally thought to be devoid of antigen presenting cells; however, putative dendritic cells (DCs) expressing enhanced yellow fluorescent protein (eYFP) are present in the retina and brain parenchyma of CD11c-eYFP mice. We previously showed that these mice carry the Crb1(rd8) mutation, which causes retinal dystrophic lesions; therefore we hypothesized that the presence of CD11c-eYFP(+) cells within the CNS may be due to pathology associated with the Crb1(rd8) mutation. We generated CD11c-eYFP Crb1(wt/wt) mice and compared the distribution and immunophenotype of CD11c-eYFP(+) cells in CD11c-eYFP mice with and without the Crb1(rd8) mutation. The number and distribution of CD11c-eYFP(+) cells in the CNS was similar between CD11c-eYFP Crb1(wt/wt) and CD11c-eYFP Crb1(rd8/rd8) mice. CD11c-eYFP(+) cells were distributed throughout the inner retina, and clustered in brain regions that receive input from the external environment or lack a blood-brain barrier. CD11c-eYFP(+) cells within the retina and cerebral cortex of CD11c-eYFP Crb1(wt/wt) mice expressed CD11b, F4/80, CD115 and Iba-1, but not DC or antigen presentation markers, whereas CD11c-eYFP(+) cells within the choroid plexus and pia mater expressed CD11c, I-A/I-E, CD80, CD86, CD103, DEC205, CD8α and CD135. The immunophenotype of CD11c-eYFP(+) cells and microglia within the CNS was similar between CD11c-eYFP Crb1(wt/wt) and CD11c-eYFP Crb1(rd8/rd8) mice; however, CD11c and I-A/I-E expression was significantly increased in CD11c-eYFP Crb1(rd8/rd8) mice. This study demonstrates that the overwhelming majority of CNS CD11c-eYFP(+) cells do not display the phenotype of DCs or their precursors and are most likely a subpopulation of microglia. GLIA 2016. GLIA 2016;64:1331-1349. PMID:27189804

  4. Neural stem cells: Brain building blocks and beyond

    PubMed Central

    Bergström, Tobias

    2012-01-01

    Neural stem cells are the origins of neurons and glia and generate all the differentiated neural cells of the mammalian central nervous system via the formation of intermediate precursors. Although less frequent, neural stem cells persevere in the postnatal brain where they generate neurons and glia. Adult neurogenesis occurs throughout life in a few limited brain regions. Regulation of neural stem cell number during central nervous system development and in adult life is associated with rigorous control. Failure in this regulation may lead to e.g. brain malformation, impaired learning and memory, or tumor development. Signaling pathways that are perturbed in glioma are the same that are important for neural stem cell self-renewal, differentiation, survival, and migration. The heterogeneity of human gliomas has impeded efficient treatment, but detailed molecular characterization together with novel stem cell-like glioma cell models that reflect the original tumor gives opportunities for research into new therapies. The observation that neural stem cells can be isolated and expanded in vitro has opened new avenues for medical research, with the hope that they could be used to compensate the loss of cells that features in several severe neurological diseases. Multipotent neural stem cells can be isolated from the embryonic and adult brain and maintained in culture in a defined medium. In addition, neural stem cells can be derived from embryonic stem cells and induced pluripotent stem cells by in vitro differentiation, thus adding to available models to study stem cells in health and disease. PMID:22512245

  5. Gene amplification during differentiation of mammalian neural stem cells in vitro and in vivo.

    PubMed

    Fischer, Ulrike; Backes, Christina; Raslan, Abdulrahman; Keller, Andreas; Meier, Carola; Meese, Eckart

    2015-03-30

    In development of amphibians and flies, gene amplification is one of mechanisms to increase gene expression. In mammalian cells, gene amplification seems to be restricted to tumorigenesis and acquiring of drug-resistance in cancer cells. Here, we report a complex gene amplification pattern in mouse neural progenitor cells during differentiation with approximately 10% of the genome involved. Half of the amplified mouse chromosome regions overlap with amplified regions previously reported in human neural progenitor cells, indicating conserved mechanisms during differentiation. Using fluorescence in situ hybridization, we verified the amplification in single cells of primary mouse mesencephalon E14 (embryonic stage) neurosphere cells during differentiation. In vivo we confirmed gene amplifications of the TRP53 gene in cryosections from mouse embryos at stage E11.5. Gene amplification is not only a cancer-related mechanism but is also conserved in evolution, occurring during differentiation of mammalian neural stem cells. PMID:25760141

  6. Early development of the neural plate, neural crest and facial region of marsupials

    PubMed Central

    SMITH, KATHLEEN K.

    2001-01-01

    Marsupial mammals have a distinctive reproductive strategy. The young are born after an exceptionally short period of organogenesis and are consequently extremely altricial. Yet because they must be functionally independent in an essentially embryonic condition, the marsupial neonate exhibits a unique suite of adaptations. In particular, certain bones of the facial region, most cranial musculature and a few additional structures are accelerated in their development. In contrast, central nervous system structures, especially the forebrain, are markedly premature at birth, resembling an embryonic d 11 or 12 mouse. This review examines the developmental processes that are modified to produce these evolutionary changes. The focus is on the early development of the neural plate, neural crest and facial region in the marsupial, Monodelphis domestica, compared with patterns reported for rodents. Neural crest begins differentiation and migration at the neural plate stage, which results in large accumulations of neural crest in the facial region at an early stage of development. The early accumulation of neural crest provides the material for the accelerated development of oral and facial structures. The first arch region is massive in the early embryo, and the development of the olfactory placode and frontonasal region is advanced relative to the forebrain region. The development of the forebrain is delayed in marsupials relative to the hindbrain or facial region. These observations illustrate how development may be modified to produce evolutionary changes that distinguish taxa. Further, they suggest that development is not necessarily highly conserved, but instead may be quite plastic. PMID:11523813

  7. Low immunogenicity of in vitro-expanded human neural cells despite high MHC expression.

    PubMed

    Odeberg, Jenny; Piao, Jing-Hua; Samuelsson, Eva-Britt; Falci, Scott; Akesson, Elisabet

    2005-04-01

    The ability to expand human neural precursor cells in vitro offers new possibilities for future cell therapies. However, concern over immunologically based rejection of in vitro-expanded human neural cells confounds their use as donor cells. Here, we demonstrate that the expression of human leukocyte antigen (HLA) class I and II molecules, but not the co-stimulatory proteins CD40, CD80 and CD86, substantially increase during expansion of neurospheres. Furthermore, peripheral lymphocytes were unresponsive when co-cultured with in vitro-expanded neural cells. Taken together, these results suggest a low immunogenicity of these cultured human neural cells despite HLA incompatibility and high HLA expression. PMID:15748938

  8. Neural Tube Defects

    MedlinePlus

    Neural tube defects are birth defects of the brain, spine, or spinal cord. They happen in the first month ... that she is pregnant. The two most common neural tube defects are spina bifida and anencephaly. In spina bifida, ...

  9. Morphological neural networks

    SciTech Connect

    Ritter, G.X.; Sussner, P.

    1996-12-31

    The theory of artificial neural networks has been successfully applied to a wide variety of pattern recognition problems. In this theory, the first step in computing the next state of a neuron or in performing the next layer neural network computation involves the linear operation of multiplying neural values by their synaptic strengths and adding the results. Thresholding usually follows the linear operation in order to provide for nonlinearity of the network. In this paper we introduce a novel class of neural networks, called morphological neural networks, in which the operations of multiplication and addition are replaced by addition and maximum (or minimum), respectively. By taking the maximum (or minimum) of sums instead of the sum of products, morphological network computation is nonlinear before thresholding. As a consequence, the properties of morphological neural networks are drastically different than those of traditional neural network models. In this paper we consider some of these differences and provide some particular examples of morphological neural network.

  10. MicroCT and microMRI imaging of a prenatal mouse model of increased brain size

    NASA Astrophysics Data System (ADS)

    López, Elisabeth K. N.; Stock, Stuart R.; Taketo, Makoto M.; Chenn, Anjen; Ravosa, Matthew J.

    2008-08-01

    There are surprisingly few experimental models of neural growth and cranial integration. This and the dearth of information regarding fetal brain development detract from a mechanistic understanding of cranial integration and its relevance to the patterning of skull form, specifically the role of encephalization on basicranial flexion. To address this shortcoming, our research uses transgenic mice expressing a stabilized form of β-catenin to isolate the effects of relative brain size on craniofacial development. These mice develop highly enlarged brains due to an increase in neural precursors, and differences between transgenic and wild-type mice are predicted to result solely from variation in brain size. Comparisons of wild-type and transgenic mice at several prenatal ages were performed using microCT (Scanco Medical MicroCT 40) and microMRI (Avance 600 WB MR spectrometer). Statistical analyses show that the larger brain of the transgenic mice is associated with a larger neurocranium and an altered basicranial morphology. However, body size and postcranial ossification do not seem to be affected by the transgene. Comparisons of the rate of postcranial and cranial ossification using microCT also point to an unexpected effect of neural growth on skull development: increased fetal encephalization may result in a compensatory decrease in the level of cranial ossification. Therefore, if other life history factors are held constant, the ontogeny of a metabolically costly structure such as a brain may occur at the expense of other cranial structures. These analyses indicate the benefits of a multifactorial approach to cranial integration using a mouse model.

  11. Hippocampal neurogenesis in the APP/PS1/nestin-GFP triple transgenic mouse model of Alzheimer's disease.

    PubMed

    Zeng, Q; Zheng, M; Zhang, T; He, G

    2016-02-01

    Alzheimer's disease (AD) is one of the most common causes of dementia. Although the exact mechanisms of AD are not entirely clear, the impairment in adult hippocampal neurogenesis has been reported to play a role in AD. To assess the relationship between AD and neurogenesis, we studied APP/PS1/nestin-green fluorescent protein (GFP) triple transgenic mice, a well-characterized mouse model of AD, which express GFP under the control of the nestin promoter. Different ages of AD mice and their wild-type littermates (WT) were used in our study. Immunofluorescent staining showed that neurogenesis occurred mainly in the subgranular zone (SGZ) of the dentate gyrus (DG) and subventricular zone (SVZ) of the lateral ventricles (LVs). The expression of neural stem cells (NSCs) (nestin) and neural precursors such as doublecortin (DCX) and GFAP in AD mice were decreased with age, as well as there being a reduction in 5-bromo-2-deoxyuridine (BrdU)-positive cells, when compared to WT. However, the number of maturate neurons (NeuN) was not significantly different between AD mice and wild-type controls, and NeuN changed only slightly with age. By Golgi-Cox staining, the morphologies of dendrites were observed, and significant differences existed between AD mice and wild-type controls. These results suggest that AD has a far-reaching influence on the regulation of adult hippocampal neurogenesis, leading to a gradual decrease in the generation of neural progenitors (NPCs), and inhibition of the differentiation and maturation of neurons. PMID:26639620

  12. Optical Neural Interfaces

    PubMed Central

    Warden, Melissa R.; Cardin, Jessica A.; Deisseroth, Karl

    2014-01-01

    Genetically encoded optical actuators and indicators have changed the landscape of neuroscience, enabling targetable control and readout of specific components of intact neural circuits in behaving animals. Here, we review the development of optical neural interfaces, focusing on hardware designed for optical control of neural activity, integrated optical control and electrical readout, and optical readout of population and single-cell neural activity in freely moving mammals. PMID:25014785

  13. Annealing of aromatic polyimide precursors

    NASA Technical Reports Server (NTRS)

    Wakelyn, N. T.

    1975-01-01

    A study has been made of the thermal behavior of polyimide precursors: an isomeric pair of crystals of the complex formed by p-phenylenediamine with the separated isomers of the di-isopropyl ester of pyromellitic acid. Specimens of this material were isothermally annealed in the temperature range 120 C to 170 C for periods of time up to 1 week. Although this temperature range is well below that customarily used for imidizations, the working hypothesis was that it would be more likely that a polymer embodying at least part of the precursor structure could be formed if the molecular motion was minimized to that actually required for the formation of the imide linkage. The progress of the annealing was followed by: infrared spectroscopy, differential thermal analysis, powder X-ray diffraction, and thermal gravimetric analysis. Single crystal X-ray analysis of the meta monomer yields a structure of chains of alternating acid and base and suggests that this monomer is amenable to polymerization with a minimum of geometrical disruption.

  14. Mapping Sub-Second Structure in Mouse Behavior.

    PubMed

    Wiltschko, Alexander B; Johnson, Matthew J; Iurilli, Giuliano; Peterson, Ralph E; Katon, Jesse M; Pashkovski, Stan L; Abraira, Victoria E; Adams, Ryan P; Datta, Sandeep Robert

    2015-12-16

    Complex animal behaviors are likely built from simpler modules, but their systematic identification in mammals remains a significant challenge. Here we use depth imaging to show that 3D mouse pose dynamics are structured at the sub-second timescale. Computational modeling of these fast dynamics effectively describes mouse behavior as a series of reused and stereotyped modules with defined transition probabilities. We demonstrate this combined 3D imaging and machine learning method can be used to unmask potential strategies employed by the brain to adapt to the environment, to capture both predicted and previously hidden phenotypes caused by genetic or neural manipulations, and to systematically expose the global structure of behavior within an experiment. This work reveals that mouse body language is built from identifiable components and is organized in a predictable fashion; deciphering this language establishes an objective framework for characterizing the influence of environmental cues, genes and neural activity on behavior. PMID:26687221

  15. Opposite Effect Of Inflammation on SVZ vs. Hippocampal Precursors In Brain Injury

    PubMed Central

    Covey, Matthew V.; Loporchio, Dean F.; Buono, Krista D.; Levison, Steven W.

    2011-01-01

    Objective Inflammation promotes epidermal wound healing but is considered detrimental to recovery from CNS injury. Sick infants have increased levels of cytokines in their CSF that correlate with poor neurological outcome. In this study we investigated the role of neuroinflammation and more specifically, IL-6, in the amplification of subventricular zone (SVZ) and subgranular zone (SGZ) neural precursors after neonatal brain injury. Methods Neonatal hypoxia/ischemia (H/I) was induced in P6 rat pups and IL-6 was quantified with or without Indomethacin administration. Neural precursor responses were evaluated by neurosphere assays as well as by stereological analyses. Studies were performed to determine how IL-6 and LIF affect SVZ cell expansion, proliferation and self-renewal. Results Consistent with earlier studies, SVZ cells expanded after H/I. Contrary to our expectations, Indomethacin significantly decreased both the initial reactive increase in these precursors as well as their ability to self-renew. By contrast, Indomethacin increased proliferation in the SGZ and lateral SVZ. Indomethacin diminished the accumulation of microglia/macrophages and IL-6 production after H/I. In vitro IL-6 enhanced neurosphere growth, self-renewal and tripotentiality and was more effective than LIF in promoting self-renewal. Enhanced precursor self-renewal also was obtained using PGE2, which is downstream of cyclooxygenase-2 and a target of Indomethacin. Interpretation These data implicate neuroinflammation and in particular IL-6 as a positive effector of primitive neural precursor expansion after neonatal brain injury. These findings have important clinical implications, as Indomethacin and other anti-inflammatory agents are administered to premature infants for a variety of reasons. PMID:21710624

  16. Patterns in neural processing

    NASA Astrophysics Data System (ADS)

    Engineer, Sunu

    2012-03-01

    In this paper we propose a model for neural processing that addresses both the evolutionary and functional aspects of neural systems that are observed in nature, from the simplest neural collections to dense large scale associations such as human brains. We propose both an architecture and a process in which these components interact to create the emergent behavior that we define as the 'mind'.

  17. Nested Neural Networks

    NASA Technical Reports Server (NTRS)

    Baram, Yoram

    1992-01-01

    Report presents analysis of nested neural networks, consisting of interconnected subnetworks. Analysis based on simplified mathematical models more appropriate for artificial electronic neural networks, partly applicable to biological neural networks. Nested structure allows for retrieval of individual subpatterns. Requires fewer wires and connection devices than fully connected networks, and allows for local reconstruction of damaged subnetworks without rewiring entire network.

  18. Cytoplasmic fragment of Alcadein α generated by regulated intramembrane proteolysis enhances amyloid β-protein precursor (APP) transport into the late secretory pathway and facilitates APP cleavage.

    PubMed

    Takei, Norio; Sobu, Yuriko; Kimura, Ayano; Urano, Satomi; Piao, Yi; Araki, Yoichi; Taru, Hidenori; Yamamoto, Tohru; Hata, Saori; Nakaya, Tadashi; Suzuki, Toshiharu

    2015-01-01

    The neural type I membrane protein Alcadein α (Alcα), is primarily cleaved by amyloid β-protein precursor (APP) α-secretase to generate a membrane-associated carboxyl-terminal fragment (Alcα CTF), which is further cleaved by γ-secretase to secrete p3-Alcα peptides and generate an intracellular cytoplasmic domain fragment (Alcα ICD) in the late secretory pathway. By association with the neural adaptor protein X11L (X11-like), Alcα and APP form a ternary complex that suppresses the cleavage of both Alcα and APP by regulating the transport of these membrane proteins into the late secretory pathway where secretases are active. However, it has not been revealed how Alcα and APP are directed from the ternary complex formed largely in the Golgi into the late secretory pathway to reach a nerve terminus. Using a novel transgenic mouse line expressing excess amounts of human Alcα CTF (hAlcα CTF) in neurons, we found that expression of hAlcα CTF induced excess production of hAlcα ICD, which facilitated APP transport into the nerve terminus and enhanced APP metabolism, including Aβ generation. In vitro cell studies also demonstrated that excess expression of Alcα ICD released both APP and Alcα from the ternary complex. These results indicate that regulated intramembrane proteolysis of Alcα by γ-secretase regulates APP trafficking and the production of Aβ in vivo. PMID:25406318

  19. Cytoplasmic Fragment of Alcadein α Generated by Regulated Intramembrane Proteolysis Enhances Amyloid β-Protein Precursor (APP) Transport into the Late Secretory Pathway and Facilitates APP Cleavage*

    PubMed Central

    Takei, Norio; Sobu, Yuriko; Kimura, Ayano; Urano, Satomi; Piao, Yi; Araki, Yoichi; Taru, Hidenori; Yamamoto, Tohru; Hata, Saori; Nakaya, Tadashi; Suzuki, Toshiharu

    2015-01-01

    The neural type I membrane protein Alcadein α (Alcα), is primarily cleaved by amyloid β-protein precursor (APP) α-secretase to generate a membrane-associated carboxyl-terminal fragment (Alcα CTF), which is further cleaved by γ-secretase to secrete p3-Alcα peptides and generate an intracellular cytoplasmic domain fragment (Alcα ICD) in the late secretory pathway. By association with the neural adaptor protein X11L (X11-like), Alcα and APP form a ternary complex that suppresses the cleavage of both Alcα and APP by regulating the transport of these membrane proteins into the late secretory pathway where secretases are active. However, it has not been revealed how Alcα and APP are directed from the ternary complex formed largely in the Golgi into the late secretory pathway to reach a nerve terminus. Using a novel transgenic mouse line expressing excess amounts of human Alcα CTF (hAlcα CTF) in neurons, we found that expression of hAlcα CTF induced excess production of hAlcα ICD, which facilitated APP transport into the nerve terminus and enhanced APP metabolism, including Aβ generation. In vitro cell studies also demonstrated that excess expression of Alcα ICD released both APP and Alcα from the ternary complex. These results indicate that regulated intramembrane proteolysis of Alcα by γ-secretase regulates APP trafficking and the production of Aβ in vivo. PMID:25406318

  20. Dynamic expression of TrkB receptor protein on proliferating and maturing cells in the adult mouse dentate gyrus

    PubMed Central

    Donovan, Michael H.; Yamaguchi, Masahiro; Eisch, Amelia J.

    2008-01-01

    Brain-derived neurotrophic factor (BDNF) is implicated in regulation of adult hippocampal neurogenesis, presumably via its primary receptor, TrkB, but controversy exists about how BDNF affects neurogenesis (e.g. proliferation vs. survival/differentiation). This controversy arises, in part, due to the lack of information about if and when TrkB is expressed on adult neural precursors in vivo. Using multiple methods to analyze proliferating and maturing cells in the adult mouse subgranular zone (SGZ), we find that the proportion of proliferating cells that are TrkB-IR is low and it remains low for at least one week following BrdU labeling, but increases as neuroblasts mature. Use of the nestin-GFP transgenic mouse revealed the likelihood of being TrkB-IR increased with presumed maturity of the cell type. Stem-like cells, which rarely divide, were likely to express TrkB. However, early progenitors and late progenitors, which are still in the cell cycle had rare TrkB expression. Immature neuroblasts, however, were more likely to express TrkB, especially as their morphology became more mature. Taken together, these findings emphasize that expression of TrkB protein is closely linked to progression towards neuronal maturity. This provides evidence that maturing cells but not proliferating cells in the adult mouse SGZ have the molecular machinery necessary to respond directly to BDNF. Furthermore, these findings lay critical groundwork for further exploration of the role of BDNF-TrkB signaling in regulation of adult hippocampal neurogenesis. PMID:18240316

  1. Multi-omics profile of the mouse dentate gyrus after kainic acid-induced status epilepticus.

    PubMed

    Schouten, Marijn; Bielefeld, Pascal; Fratantoni, Silvina A; Hubens, Chantal J; Piersma, Sander R; Pham, Thang V; Voskuyl, Rob A; Lucassen, Paul J; Jimenez, Connie R; Fitzsimons, Carlos P

    2016-01-01

    Temporal lobe epilepsy (TLE) can develop from alterations in hippocampal structure and circuit characteristics, and can be modeled in mice by administration of kainic acid (KA). Adult neurogenesis in the dentate gyrus (DG) contributes to hippocampal functions and has been reported to contribute to the development of TLE. Some of the phenotypical changes include neural stem and precursor cells (NPSC) apoptosis, shortly after their birth, before they produce hippocampal neurons. Here we explored these early phenotypical changes in the DG 3 days after a systemic injection of KA inducing status epilepticus (KA-SE), in mice. We performed a multi-omics experimental setup and analyzed DG tissue samples using proteomics, transcriptomics and microRNA profiling techniques, detecting the expression of 2327 proteins, 13401 mRNAs and 311 microRNAs. We here present a description of how these data were obtained and make them available for further analysis and validation. Our data may help to further identify and characterize molecular mechanisms involved in the alterations induced shortly after KA-SE in the mouse DG. PMID:27529540

  2. Multi-omics profile of the mouse dentate gyrus after kainic acid-induced status epilepticus

    PubMed Central

    Schouten, Marijn; Bielefeld, Pascal; Fratantoni, Silvina A.; Hubens, Chantal J.; Piersma, Sander R.; Pham, Thang V.; Voskuyl, Rob A.; Lucassen, Paul J.; Jimenez, Connie R.; Fitzsimons, Carlos P.

    2016-01-01

    Temporal lobe epilepsy (TLE) can develop from alterations in hippocampal structure and circuit characteristics, and can be modeled in mice by administration of kainic acid (KA). Adult neurogenesis in the dentate gyrus (DG) contributes to hippocampal functions and has been reported to contribute to the development of TLE. Some of the phenotypical changes include neural stem and precursor cells (NPSC) apoptosis, shortly after their birth, before they produce hippocampal neurons. Here we explored these early phenotypical changes in the DG 3 days after a systemic injection of KA inducing status epilepticus (KA-SE), in mice. We performed a multi-omics experimental setup and analyzed DG tissue samples using proteomics, transcriptomics and microRNA profiling techniques, detecting the expression of 2327 proteins, 13401 mRNAs and 311 microRNAs. We here present a description of how these data were obtained and make them available for further analysis and validation. Our data may help to further identify and characterize molecular mechanisms involved in the alterations induced shortly after KA-SE in the mouse DG. PMID:27529540

  3. Oligodendroglial and Pan-neural Crest Expression of Cre Recombinase Directed by Sox10 Enhancer

    PubMed Central

    Stine, Zachary E.; Huynh, Jimmy L.; Loftus, Stacie K.; Gorkin, David U.; Salmasi, Amirali H.; Novak, Thomas; Purves, Todd; Miller, Ronald A.; Antonellis, Anthony; Gearhart, John P.; Pavan, William J.; McCallion, Andrew S.

    2010-01-01

    Utilizing a recently identified Sox10 distal enhancer directing Cre expression, we report S4F:Cre, a transgenic mouse line capable of inducing recombination in oligodendroglia and all examined neural crest derived tissues. Assayed using R26R:LacZ reporter mice expression was detected in neural crest derived tissues including the forming facial skeleton, dorsal root ganglia, sympathetic ganglia, enteric nervous system, aortae and melanoblasts, consistent with Sox10 expression. LacZ reporter expression was also detected in non-neural crest derived tissues including the oligodendrocytes and the ventral neural tube. This line provides appreciable differences in Cre expression pattern from other transgenic mouse lines that mark neural crest populations, including additional populations defined by the expression of other SoxE proteins. The S4F:Cre transgenic line will thus serve as a powerful tool for lineage tracing, gene function characterization and genome manipulation in these populations. PMID:19830815

  4. Ganglioside-Dependent Neural Stem Cell Proliferation in Alzheimer's Disease Model Mice.

    PubMed

    Koon, Noah A; Itokazu, Yutaka; Yu, Robert K

    2015-01-01

    The aggregation and formation of amyloid plaques by amyloid β-peptides (Aβs) is believed to be one of the pathological hallmarks of Alzheimer's disease (AD). Intriguingly, Aβs have also been shown to possess proliferative effects on neural stem cells (NSCs). Many essential cellular processes in NSCs, such as fate determination and proliferation, are heavily influenced by cell surface glycoconjugates, including gangliosides. It has recently been shown that Aβ1-42 alters several key glycosyltransferases and glycosidases. To further define the effects of Aβs and to clarify the potential mechanisms of action of those peptides on NSCs, NSCs were cultured from embryonic brains of the double-transgenic mouse model of AD [B6C3-Tg(APPswe,PSEN1dE9)85Dbo/J] coexpressing mutants of amyloid precursor protein (APPswe) and presenilin1 (PSEN1dE9). We found that Aβs not only promoted cell proliferation but also altered expression of several key glycogenes for glycoconjugate metabolism, such as sialyltransferases II and III (ST-II & -III) in AD NSCs. In addition, we found upregulation of epidermal growth factor receptor and Notch1 intracellular domain. Moreover, the increased expression of ST-II and -III coincided with the elevated levels of c-series gangliosides (A2B5+ antigens) in AD NSCs. Further, we revealed that epidermal growth factor signaling and gangliosides are necessary components on Aβ-stimulated NSC proliferation. Our present study has thus provided a novel mechanism for the upregulation of c-series ganglioside expression and increases in several NSC markers to account for the proliferative effect of Aβs on NSCs in AD mouse brain. These observations support the potential beneficial effects of Aβs and gangliosides in promoting neurogenesis in AD brain. PMID:26699276

  5. Mouse Curve Biometrics

    SciTech Connect

    Schulz, Douglas A.

    2007-10-08

    A biometric system suitable for validating user identity using only mouse movements and no specialized equipment is presented. Mouse curves (mouse movements with little or no pause between them) are individually classied and used to develop classication histograms, which are representative of an individual's typical mouse use. These classication histograms can then be compared to validate identity. This classication approach is suitable for providing continuous identity validation during an entire user session.

  6. Premarital precursors of marital infidelity.

    PubMed

    Allen, Elizabeth S; Rhoades, Galena Kline; Stanley, Scott M; Markman, Howard J; Williams, Tamara; Melton, Jessica; Clements, Mari L

    2008-06-01

    Premarital precursors of infidelity were evaluated in a sample of 72 couples (N = 144) who were taking part in a longitudinal study of marriage. Premarital self-report and observational data were compared for couples who experienced infidelity and those who did not experience infidelity in the first years of marriage. Couples in which the male engaged in marital infidelity were characterized, premaritally, by significantly lower male sexual satisfaction, lower male positive communication, and higher female invalidation, whereas couples in which the female went on to engage in infidelity were characterized, premaritally, by significantly lower levels of female positive communication, higher levels of male and female negative communication, and higher levels of male and female invalidation. Implications of the findings for future research on the prediction and prevention of infidelity are discussed. PMID:18605124

  7. Precursors for Carbon Nitride Synthesis

    SciTech Connect

    Prashantha, M.; Gopal, E. S. R.; Ramesh, K.

    2011-07-15

    Nano structured carbon nitride films were prepared by pyrolysis assisted chemical vapour deposition. Pyrrole (C{sub 4}H{sub 5}N), Pyrrolidine (C{sub 4}H{sub 9}N), Azabenzimidazole (C{sub 6}H{sub 5}N{sub 3}) and Triazine (C{sub 6}H{sub 15}N{sub 3}) were used as precursors. The vibrational modes observed for C-N and C = N from FTIR spectra confirms the bonding of nitrogen with carbon. XPS core level spectra of C 1s and N 1s also show the formation of bonding between carbon and nitrogen atoms. The nitrogen content in the prepared samples was found to be around 25 atomic %.

  8. Building a Brainier Mouse.

    ERIC Educational Resources Information Center

    Tsien, Joe Z.

    2000-01-01

    Describes a genetic engineering project to build an intelligent mouse. Cites understanding the molecular basis of learning and memory as a very important step. Concludes that while science will never create a genius mouse that plays the stock market, it can turn a mouse into a quick learner with a better memory. (YDS)

  9. Loss of T cell precursors after spaceflight and exposure to vector-averaged gravity

    NASA Technical Reports Server (NTRS)

    Woods, Chris C.; Banks, Krista E.; Gruener, Raphael; DeLuca, Dominick

    2003-01-01

    Using fetal thymus organ culture (FTOC), we examined the effects of spaceflight and vector-averaged gravity on T cell development. Under both conditions, the development of T cells was significantly attenuated. Exposure to spaceflight for 16 days resulted in a loss of precursors for CD4+, CD8+, and CD4+CD8+ T cells in a rat/mouse xenogeneic co-culture. A significant decrease in the same precursor cells, as well as a decrease in CD4-CD8- T cell precursors, was also observed in a murine C57BL/6 FTOC after rotation in a clinostat to produce a vector-averaged microgravity-like environment. The block in T cell development appeared to occur between the pre-T cell and CD4+CD8+ T cell stage. These data indicate that gravity plays a decisive role in the development of T cells.

  10. Functional analyses and treatment of precursor behavior.

    PubMed

    Najdowski, Adel C; Wallace, Michele D; Ellsworth, Carrie L; MacAleese, Alicia N; Cleveland, Jackie M

    2008-01-01

    Functional analysis has been demonstrated to be an effective method to identify environmental variables that maintain problem behavior. However, there are cases when conducting functional analyses of severe problem behavior may be contraindicated. The current study applied functional analysis procedures to a class of behavior that preceded severe problem behavior (precursor behavior) and evaluated treatments based on the outcomes of the functional analyses of precursor behavior. Responding for all participants was differentiated during the functional analyses, and individualized treatments eliminated precursor behavior. These results suggest that functional analysis of precursor behavior may offer an alternative, indirect method to assess the operant function of severe problem behavior. PMID:18468282

  11. 1994 Accident sequence precursor program results

    SciTech Connect

    Belles, R.J.; Cletcher, J.W.; Copinger, D.A.

    1996-01-01

    The Accident Sequence Precursor (ASP) Program involves the systematic review and evaluation of operational events that have occurred at light-water reactors to identify and categorize precursors to potential severe core damage accident sequences. The results of the ASP Program are published in an annual report. The most recent report, which contains the analyses of the precursors for 1994, is NUREG/CR-4674, Vols. 21 and 22, Precursors to Potential Severe Core Damage Accidents: 1994, A Status Report, published in December 1995. This article provides an overview of the ASP review and evaluation process and a summary of the results for 1994. 12 refs., 2 figs., 4 tabs.

  12. 1995 Accident Sequence Precursor (ASP) Program results

    SciTech Connect

    Muhlheim, M.D.; Belles, R.J.; Cletcher, J.W.; Copinger, D.A.; O`Reilly, P.D.; Dolan, B.W.; Minarick, J.W.

    1997-01-01

    The Accident Sequence Precursor (ASP) Program involves the systematic review and evaluation of operational events that have occurred at light-water reactors to identify and categorize precursors to potential severe core damage accident sequences. The results of the ASP Program are published in an annual report. The most recent report, which contains the precursors for 1995, is NUREG/CR-4674, Volume 23, Precursors to Potential Severe Core Damage Accidents: 1995, A Status Report, published in April 1997. This article provides an overview of the ASP review and evaluation process and a summary of the results for 1995.

  13. Biology and pathophysiology of the amyloid precursor protein

    PubMed Central

    2011-01-01

    The amyloid precursor protein (APP) plays a central role in the pathophysiology of Alzheimer's disease in large part due to the sequential proteolytic cleavages that result in the generation of β-amyloid peptides (Aβ). Not surprisingly, the biological properties of APP have also been the subject of great interest and intense investigations. Since our 2006 review, the body of literature on APP continues to expand, thereby offering further insights into the biochemical, cellular and functional properties of this interesting molecule. Sophisticated mouse models have been created to allow in vivo examination of cell type-specific functions of APP together with the many functional domains. This review provides an overview and update on our current understanding of the pathobiology of APP. PMID:21527012

  14. Neuronal Representation of Ultraviolet Visual Stimuli in Mouse Primary Visual Cortex

    PubMed Central

    Tan, Zhongchao; Sun, Wenzhi; Chen, Tsai-Wen; Kim, Douglas; Ji, Na

    2015-01-01

    The mouse has become an important model for understanding the neural basis of visual perception. Although it has long been known that mouse lens transmits ultraviolet (UV) light and mouse opsins have absorption in the UV band, little is known about how UV visual information is processed in the mouse brain. Using a custom UV stimulation system and in vivo calcium imaging, we characterized the feature selectivity of layer 2/3 neurons in mouse primary visual cortex (V1). In adult mice, a comparable percentage of the neuronal population responds to UV and visible stimuli, with similar pattern selectivity and receptive field properties. In young mice, the orientation selectivity for UV stimuli increased steadily during development, but not direction selectivity. Our results suggest that, by expanding the spectral window through which the mouse can acquire visual information, UV sensitivity provides an important component for mouse vision. PMID:26219604

  15. Neuronal Representation of Ultraviolet Visual Stimuli in Mouse Primary Visual Cortex.

    PubMed

    Tan, Zhongchao; Sun, Wenzhi; Chen, Tsai-Wen; Kim, Douglas; Ji, Na

    2015-01-01

    The mouse has become an important model for understanding the neural basis of visual perception. Although it has long been known that mouse lens transmits ultraviolet (UV) light and mouse opsins have absorption in the UV band, little is known about how UV visual information is processed in the mouse brain. Using a custom UV stimulation system and in vivo calcium imaging, we characterized the feature selectivity of layer 2/3 neurons in mouse primary visual cortex (V1). In adult mice, a comparable percentage of the neuronal population responds to UV and visible stimuli, with similar pattern selectivity and receptive field properties. In young mice, the orientation selectivity for UV stimuli increased steadily during development, but not direction selectivity. Our results suggest that, by expanding the spectral window through which the mouse can acquire visual information, UV sensitivity provides an important component for mouse vision. PMID:26219604

  16. CBP histone acetyltransferase activity regulates embryonic neural differentiation in the normal and Rubinstein-Taybi syndrome brain.

    PubMed

    Wang, Jing; Weaver, Ian C G; Gauthier-Fisher, Andrée; Wang, Haoran; He, Ling; Yeomans, John; Wondisford, Frederic; Kaplan, David R; Miller, Freda D

    2010-01-19

    Increasing evidence indicates that epigenetic changes regulate cell genesis. Here, we ask about neural precursors, focusing on CREB binding protein (CBP), a histone acetyltransferase that, when haploinsufficient, causes Rubinstein-Taybi syndrome (RTS), a genetic disorder with cognitive dysfunction. We show that neonatal cbp(+/-) mice are behaviorally impaired, displaying perturbed vocalization behavior. cbp haploinsufficiency or genetic knockdown with siRNAs inhibited differentiation of embryonic cortical precursors into all three neural lineages, coincident with decreased CBP binding and histone acetylation at promoters of neuronal and glial genes. Inhibition of histone deacetylation rescued these deficits. Moreover, CBP phosphorylation by atypical protein kinase C zeta was necessary for histone acetylation at neural gene promoters and appropriate differentiation. These data support a model in which environmental cues regulate CBP activity and histone acetylation to control neural precursor competency to differentiate, and indicate that cbp haploinsufficiency disrupts this mechanism, thereby likely causing cognitive dysfunction in RTS. PMID:20152182

  17. Evolvable Neural Software System

    NASA Technical Reports Server (NTRS)

    Curtis, Steven A.

    2009-01-01

    The Evolvable Neural Software System (ENSS) is composed of sets of Neural Basis Functions (NBFs), which can be totally autonomously created and removed according to the changing needs and requirements of the software system. The resulting structure is both hierarchical and self-similar in that a given set of NBFs may have a ruler NBF, which in turn communicates with other sets of NBFs. These sets of NBFs may function as nodes to a ruler node, which are also NBF constructs. In this manner, the synthetic neural system can exhibit the complexity, three-dimensional connectivity, and adaptability of biological neural systems. An added advantage of ENSS over a natural neural system is its ability to modify its core genetic code in response to environmental changes as reflected in needs and requirements. The neural system is fully adaptive and evolvable and is trainable before release. It continues to rewire itself while on the job. The NBF is a unique, bilevel intelligence neural system composed of a higher-level heuristic neural system (HNS) and a lower-level, autonomic neural system (ANS). Taken together, the HNS and the ANS give each NBF the complete capabilities of a biological neural system to match sensory inputs to actions. Another feature of the NBF is the Evolvable Neural Interface (ENI), which links the HNS and ANS. The ENI solves the interface problem between these two systems by actively adapting and evolving from a primitive initial state (a Neural Thread) to a complicated, operational ENI and successfully adapting to a training sequence of sensory input. This simulates the adaptation of a biological neural system in a developmental phase. Within the greater multi-NBF and multi-node ENSS, self-similar ENI s provide the basis for inter-NBF and inter-node connectivity.

  18. Human pluripotent stem cell-derived neural constructs for predicting neural toxicity.

    PubMed

    Schwartz, Michael P; Hou, Zhonggang; Propson, Nicholas E; Zhang, Jue; Engstrom, Collin J; Santos Costa, Vitor; Jiang, Peng; Nguyen, Bao Kim; Bolin, Jennifer M; Daly, William; Wang, Yu; Stewart, Ron; Page, C David; Murphy, William L; Thomson, James A

    2015-10-01

    Human pluripotent stem cell-based in vitro models that reflect human physiology have the potential to reduce the number of drug failures in clinical trials and offer a cost-effective approach for assessing chemical safety. Here, human embryonic stem (ES) cell-derived neural progenitor cells, endothelial cells, mesenchymal stem cells, and microglia/macrophage precursors were combined on chemically defined polyethylene glycol hydrogels and cultured in serum-free medium to model cellular interactions within the developing brain. The precursors self-assembled into 3D neural constructs with diverse neuronal and glial populations, interconnected vascular networks, and ramified microglia. Replicate constructs were reproducible by RNA sequencing (RNA-Seq) and expressed neurogenesis, vasculature development, and microglia genes. Linear support vector machines were used to construct a predictive model from RNA-Seq data for 240 neural constructs treated with 34 toxic and 26 nontoxic chemicals. The predictive model was evaluated using two standard hold-out testing methods: a nearly unbiased leave-one-out cross-validation for the 60 training compounds and an unbiased blinded trial using a single hold-out set of 10 additional chemicals. The linear support vector produced an estimate for future data of 0.91 in the cross-validation experiment and correctly classified 9 of 10 chemicals in the blinded trial. PMID:26392547

  19. Human pluripotent stem cell-derived neural constructs for predicting neural toxicity

    PubMed Central

    Schwartz, Michael P.; Hou, Zhonggang; Propson, Nicholas E.; Zhang, Jue; Engstrom, Collin J.; Costa, Vitor Santos; Jiang, Peng; Nguyen, Bao Kim; Bolin, Jennifer M.; Daly, William; Wang, Yu; Stewart, Ron; Page, C. David; Murphy, William L.; Thomson, James A.

    2015-01-01

    Human pluripotent stem cell-based in vitro models that reflect human physiology have the potential to reduce the number of drug failures in clinical trials and offer a cost-effective approach for assessing chemical safety. Here, human embryonic stem (ES) cell-derived neural progenitor cells, endothelial cells, mesenchymal stem cells, and microglia/macrophage precursors were combined on chemically defined polyethylene glycol hydrogels and cultured in serum-free medium to model cellular interactions within the developing brain. The precursors self-assembled into 3D neural constructs with diverse neuronal and glial populations, interconnected vascular networks, and ramified microglia. Replicate constructs were reproducible by RNA sequencing (RNA-Seq) and expressed neurogenesis, vasculature development, and microglia genes. Linear support vector machines were used to construct a predictive model from RNA-Seq data for 240 neural constructs treated with 34 toxic and 26 nontoxic chemicals. The predictive model was evaluated using two standard hold-out testing methods: a nearly unbiased leave-one-out cross-validation for the 60 training compounds and an unbiased blinded trial using a single hold-out set of 10 additional chemicals. The linear support vector produced an estimate for future data of 0.91 in the cross-validation experiment and correctly classified 9 of 10 chemicals in the blinded trial. PMID:26392547

  20. Leading time domain seismic precursors

    NASA Astrophysics Data System (ADS)

    Boucouvalas, A. C.; Gkasios, M.; Keskebes, A.; Tselikas, N. T.

    2014-08-01

    The problem of predicting the occurrence of earthquakes is threefold. On one hand it is necessary to predict the date and magnitude of an earthquake, and on the other hand the location of the epicenter. In this work after a brief review of the state of earthquake prediction research, we report on a new leading time precursor for determining time onset of earthquake occurrence. We report the linking between earthquakes of the past with those which happen in the future via Fibonacci, Dual and Lucas numbers (FDL) numbers. We demonstrate it here with two example seed earthquakes at least 100 years old. Using this leading indicator method we can predict significant earthquake events >6.5R, with good accuracy approximately +- 1 day somewhere in the world. From a single seed we produce at least 100 trials simultaneously of which 50% are correct to +- 1day. The indicator is based on Fibonacci, Dual and Lucas numbers (FDL). This result hints that the log periodic FDL numbers are at the root of the understanding of the earthquake mechanism. The theory is based on the assumption that each occurred earthquake discontinuity can be thought of as a generating source of FDL time series. (The mechanism could well be linked to planetary orbits). When future dates are derived from clustering and convergence from previous strong earthquake dates at an FDL time distance, then we have a high probability for an earthquake to occur on that date. We set up a real time system which generates FDL time series from each previous significant earthquake (>7R) and we produce a year to year calendar of high probability earthquake dates. We have tested this over a number of years with considerable success. We have applied this technique for strong (>7R) earthquakes across the globe as well as on a restricted region such as the Greek geographic region where the magnitude is small (>4R-6.5R). In both cases the success of the method is impressive. It is our belief that supplementing this method with

  1. ACAM, a novel member of the neural IgCAM family, mediates anterior neural tube closure in a primitive chordate.

    PubMed

    Morales Diaz, Heidi; Mejares, Emil; Newman-Smith, Erin; Smith, William C

    2016-01-01

    The neural IgCAM family of cell adhesion molecules, which includes NCAM and related molecules, has evolved via gene duplication and alternative splicing to allow for a wide range of isoforms with distinct functions and homophilic binding properties. A search for neural IgCAMs in ascidians (Ciona intestinalis, Ciona savignyi, and Phallusia mammillata) has identified a novel set of truncated family members that, unlike the known members, lack fibronectin III domains and consist of only repeated Ig domains. Within the tunicates this form appears to be unique to the ascidians, and it was designated ACAM, for Ascidian Cell Adhesion Molecule. In C. intestinalis ACAM is expressed in the developing neural plate and neural tube, with strongest expression in the anterior sensory vesicle precursor. Unlike the two other conventional neural IgCAMs in C. intestinalis, which are expressed maternally and throughout the morula and blastula stages, ACAM expression initiates at the gastrula stage. Moreover, C. intestinalis ACAM is a target of the homeodomain transcription factor OTX, which plays an essential role in the development of the anterior central nervous system. Morpholino (MO) knockdown shows that ACAM is required for neural tube closure. In MO-injected embryos neural tube closure was normal caudally, but the anterior neuropore remained open. A similar phenotype was seen with overexpression of a secreted version of ACAM. The presence of ACAM in ascidians highlights the diversity of this gene family in morphogenesis and neurodevelopment. PMID:26542009

  2. The Interrelationships of Mathematical Precursors in Kindergarten

    ERIC Educational Resources Information Center

    Cirino, Paul T.

    2011-01-01

    This study evaluated the interrelations among cognitive precursors across quantitative, linguistic, and spatial attention domains that have been implicated for math achievement in young children. The dimensionality of the quantity precursors was evaluated in 286 kindergarteners via latent variable techniques, and the contribution of precursors…

  3. Precursors in gas-liquid mixtures

    NASA Astrophysics Data System (ADS)

    Gasenko, V. G.; Gorelik, R. S.; Nakoryakov, V. E.; Timkin, L. S.

    2013-10-01

    Two types of precursors propagating at the speed of sound in a pure liquid have been revealed in the experiments on the evolution of pressure pulses in a gas-liquid mixture; at the same time, the main pressure pulse propagates at a low equilibrium speed of sound and its evolution is described by the Burgers-Korteweg-de Vries equation. The first high-frequency precursor is a complete analog of a classical Sommerfeld precursor, because the resonance dispersion equation for a bubble mixture coincides with that for insulators in the Lorentz model, and oscillates at a frequency close to the "plasma frequency." The second low-frequency precursor has been revealed in this work. The frequency of the low-frequency precursor is close to the resonance frequency of pulsations of bubbles, which is almost an order of magnitude lower than the frequency of the high-frequency precursor. The low-frequency precursor has a much larger amplitude of pulsations and smaller damping and is not described within the homogeneous model of the gas-liquid mixture. The observed phenomenon of low-frequency precursors has been explained within a simple heterogeneous model of a bubble liquid.

  4. Precursors and adjuncts of a lunar base

    NASA Technical Reports Server (NTRS)

    Burke, J. D.

    1988-01-01

    The automated, teleoperated, robotic and human-tended subsystems which will precede and accompany a lunar base program are discussed. The information about lunar conditions that can be provided by such precursors and adjuncts is addressed. The use of precursors and adjuncts for communications and navigation, for safety and survival, for lunar archives, and for entertainment and leisure is examined.

  5. Intersectional Illumination of Neural Circuit Function

    PubMed Central

    Allen, William E.; Luo, Liqun

    2016-01-01

    Molecular tools that measure and manipulate activities are widely used to dissect neural circuit function. In mice, these molecular tools are expressed from viral vectors or as transgenes. Compared to viral transduction, transgene expression offers less animal-to-animal variability and broader patterns but usually cannot achieve as high expression levels and often has broader cell type specificity. Madisen et al. (2015) report the construction of several new transgenic mouse lines that apply intersectional genetic tools to achieve high levels of expression and specificity, providing a useful resource for future studies. PMID:25741716

  6. Bone Morphogenetic Protein 4 Signalling in Neural Stem and Progenitor Cells during Development and after Injury

    PubMed Central

    Cole, Alistair E.; Murray, Simon S.; Xiao, Junhua

    2016-01-01

    Substantial progress has been made in identifying the extracellular signalling pathways that regulate neural stem and precursor cell biology in the central nervous system (CNS). The bone morphogenetic proteins (BMPs), in particular BMP4, are key players regulating neuronal and glial cell development from neural precursor cells in the embryonic, postnatal, and injured CNS. Here we review recent studies on BMP4 signalling in the generation of neurons, astrocytes, and oligodendroglial cells in the CNS. We also discuss putative mechanisms that BMP4 may utilise to influence glial cell development following CNS injury and highlight some questions for further research. PMID:27293450

  7. Anorectic activity of prostaglandin precursors.

    PubMed Central

    Doggett, N S; Jawaharlal, K

    1977-01-01

    1 Intraperitoneal and intragastric (i.g.) administration of prostaglandin precursors arachidonic (2 mg, 15 mg/kg, i.p; 30 mg/kg i.g.), linolenic (100 mg/kg i.p.; 200 mg/kg, i.g.) and linoleic (15, 100 mg/kg, i.p.; 100 mg/kg, i.g.) acids to 22 h food-deprived rats inhibits food intake. 2 This anorexia is similar to that induced by prostaglandin F2alpha (1 mg/kg, i.p.). 3 At anorectic doses these fatty acids do not cause pyrexia, in fact arachidonic acid causes hypothermia. 4 Prior treatment with indomethacin (15 mg/kg) and paracetamol (50 mg/kg) specifically reverses the anorexia and the behavioural satiety induced by the three fatty acids, while not affecting prostaglandin F2alpha-induced suppression of food intake. 5 Results of the present experiments suggest that both physiological and pharmacological modification of appetite could be brought about through an effect on prostaglandin generating systems. PMID:890209

  8. Precursor films in wetting phenomena.

    PubMed

    Popescu, M N; Oshanin, G; Dietrich, S; Cazabat, A-M

    2012-06-20

    The spontaneous spreading of non-volatile liquid droplets on solid substrates poses a classic problem in the context of wetting phenomena. It is well known that the spreading of a macroscopic droplet is in many cases accompanied by a thin film of macroscopic lateral extent, the so-called precursor film, which emanates from the three-phase contact line region and spreads ahead of the latter with a much higher speed. Such films have been usually associated with liquid-on-solid systems, but in the last decade similar films have been reported to occur in solid-on-solid systems. While the situations in which the thickness of such films is of mesoscopic size are fairly well understood, an intriguing and yet to be fully understood aspect is the spreading of microscopic, i.e. molecularly thin, films. Here we review the available experimental observations of such films in various liquid-on-solid and solid-on-solid systems, as well as the corresponding theoretical models and studies aimed at understanding their formation and spreading dynamics. Recent developments and perspectives for future research are discussed. PMID:22627067

  9. Classification of precursors in nanoscale droplets

    NASA Astrophysics Data System (ADS)

    Isele-Holder, Rolf E.; Ismail, Ahmed E.

    2016-04-01

    Molecular precursors, ultrathin films that precede spreading droplets, are still far from being understood, despite intensive study. The inherent microscopic length scales make small-scale experimental techniques and molecular simulation ideal methods to study this phenomenon. Previous work on molecular precursors using nanoscale droplets, however, consistently suffers from incorrect measurement of the dimensions of the precursor film. An alternative method to accurately characterize the precursor film is presented here. In contrast to previous measures, this method (i) allows for easy detection and characterization of precursors and (ii) yields wetting dynamics that agree with experimental observations. Finally, we briefly comment on previous studies whose conclusions may merit reconsideration in light of the present work.

  10. The Interrelationships of Mathematical Precursors in Kindergarten

    PubMed Central

    Cirino, Paul T.

    2011-01-01

    This study evaluated the interrelations among cognitive precursors across quantitative, linguistic, and spatial attention domains that have been implicated for math achievement in young children. The dimensionality of the quantity precursors was evaluated in 286 Kindergarteners via latent variable techniques, and the contribution of precursors from each domain was established for small sums addition. Results showed a five factor structure for the quantity precursors with the major distinction between nonsymbolic and symbolic tasks. The overall model demonstrated good fit, and strong predictive power (R2 = 55%) for addition number combinations. Linguistic and spatial attention domains showed indirect relationships with outcomes, with their effects mediated by symbolic quantity measures. These results have implications for the measurement of mathematical precursors, and yield promise for predicting future math performance. PMID:21194711

  11. Method of texturing a superconductive oxide precursor

    DOEpatents

    DeMoranville, Kenneth L.; Li, Qi; Antaya, Peter D.; Christopherson, Craig J.; Riley, Jr., Gilbert N.; Seuntjens, Jeffrey M.

    1999-01-01

    A method of forming a textured superconductor wire includes constraining an elongated superconductor precursor between two constraining elongated members placed in contact therewith on opposite sides of the superconductor precursor, and passing the superconductor precursor with the two constraining members through flat rolls to form the textured superconductor wire. The method includes selecting desired cross-sectional shape and size constraining members to control the width of the formed superconductor wire. A textured superconductor wire formed by the method of the invention has regular-shaped, curved sides and is free of flashing. A rolling assembly for single-pass rolling of the elongated precursor superconductor includes two rolls, two constraining members, and a fixture for feeding the precursor superconductor and the constraining members between the rolls. In alternate embodiments of the invention, the rolls can have machined regions which will contact only the elongated constraining members and affect the lateral deformation and movement of those members during the rolling process.

  12. Exploring neural network technology

    SciTech Connect

    Naser, J.; Maulbetsch, J.

    1992-12-01

    EPRI is funding several projects to explore neural network technology, a form of artificial intelligence that some believe may mimic the way the human brain processes information. This research seeks to provide a better understanding of fundamental neural network characteristics and to identify promising utility industry applications. Results to date indicate that the unique attributes of neural networks could lead to improved monitoring, diagnostic, and control capabilities for a variety of complex utility operations. 2 figs.

  13. Fuzzy and neural control

    NASA Technical Reports Server (NTRS)

    Berenji, Hamid R.

    1992-01-01

    Fuzzy logic and neural networks provide new methods for designing control systems. Fuzzy logic controllers do not require a complete analytical model of a dynamic system and can provide knowledge-based heuristic controllers for ill-defined and complex systems. Neural networks can be used for learning control. In this chapter, we discuss hybrid methods using fuzzy logic and neural networks which can start with an approximate control knowledge base and refine it through reinforcement learning.

  14. Electrophysiological precursors of social conformity.

    PubMed

    Shestakova, Anna; Rieskamp, Jörg; Tugin, Sergey; Ossadtchi, Alexey; Krutitskaya, Janina; Klucharev, Vasily

    2013-10-01

    Humans often change their beliefs or behavior due to the behavior or opinions of others. This study explored, with the use of human event-related potentials (ERPs), whether social conformity is based on a general performance-monitoring mechanism. We tested the hypothesis that conflicts with a normative group opinion evoke a feedback-related negativity (FRN) often associated with performance monitoring and subsequent adjustment of behavior. The experimental results show that individual judgments of facial attractiveness were adjusted in line with a normative group opinion. A mismatch between individual and group opinions triggered a frontocentral negative deflection with the maximum at 200 ms, similar to FRN. Overall, a conflict with a normative group opinion triggered a cascade of neuronal responses: from an earlier FRN response reflecting a conflict with the normative opinion to a later ERP component (peaking at 380 ms) reflecting a conforming behavioral adjustment. These results add to the growing literature on neuronal mechanisms of social influence by disentangling the conflict-monitoring signal in response to the perceived violation of social norms and the neural signal of a conforming behavioral adjustment. PMID:22683703

  15. Migratory neuronal progenitors arise from the neural plate borders in tunicates.

    PubMed

    Stolfi, Alberto; Ryan, Kerrianne; Meinertzhagen, Ian A; Christiaen, Lionel

    2015-11-19

    The neural crest is an evolutionary novelty that fostered the emergence of vertebrate anatomical innovations such as the cranium and jaws. During embryonic development, multipotent neural crest cells are specified at the lateral borders of the neural plate before delaminating, migrating and differentiating into various cell types. In invertebrate chordates (cephalochordates and tunicates), neural plate border cells express conserved factors such as Msx, Snail and Pax3/7 and generate melanin-containing pigment cells, a derivative of the neural crest in vertebrates. However, invertebrate neural plate border cells have not been shown to generate homologues of other neural crest derivatives. Thus, proposed models of neural crest evolution postulate vertebrate-specific elaborations on an ancestral neural plate border program, through acquisition of migratory capabilities and the potential to generate several cell types. Here we show that a particular neuronal cell type in the tadpole larva of the tunicate Ciona intestinalis, the bipolar tail neuron, shares a set of features with neural-crest-derived spinal ganglia neurons in vertebrates. Bipolar tail neuron precursors derive from caudal neural plate border cells, delaminate and migrate along the paraxial mesoderm on either side of the neural tube, eventually differentiating into afferent neurons that form synaptic contacts with both epidermal sensory cells and motor neurons. We propose that the neural plate borders of the chordate ancestor already produced migratory peripheral neurons and pigment cells, and that the neural crest evolved through the acquisition of a multipotent progenitor regulatory state upstream of multiple, pre-existing neural plate border cell differentiation programs. PMID:26524532

  16. Migratory neuronal progenitors arise from the neural plate borders in tunicates

    PubMed Central

    Stolfi, Alberto; Ryan, Kerrianne; Meinertzhagen, Ian A.; Christiaen, Lionel

    2015-01-01

    The neural crest is an evolutionary novelty that fostered the emergence of vertebrate anatomical innovations such as the cranium and jaws1. During embryonic development, multipotent neural crest cells are specified at the lateral borders of the neural plate before delaminating, migrating, and differentiating into various cell types. In invertebrate chordates (cephalochordates and tunicates), neural plate border cells express conserved factors such as Msx, Snail, and Pax3/7 and generate melanin-containing pigment cells2-4, a derivative of the neural crest in vertebrates. However, invertebrate neural plate border cells have not been shown to generate homologues of other neural crest derivatives. Thus, proposed models of neural crest evolution postulate vertebrate-specific elaborations on an ancestral neural plate border program, through acquisition of migratory capabilities and the potential to generate multiple cell types5-7. Here we show that a particular neuronal cell type in the tadpole larva of the tunicate Ciona intestinalis, the bipolar tail neuron, shares a set of features with neural crest-derived spinal ganglia neurons in vertebrates. Bipolar tail neuron precursors derive from caudal neural plate border cells, delaminate, and migrate along the paraxial mesoderm on either side of the neural tube, eventually differentiating into afferent neurons that form synaptic contacts with both epidermal sensory cells and motor neurons. We propose that the neural plate borders of the chordate ancestor already produced migratory peripheral neurons and pigment cells, and that the neural crest evolved through the acquisition of a multipotent progenitor regulatory state upstream of multiple, pre-existing neural plate border cell differentiation programs. PMID:26524532

  17. Computing with Neural Synchrony

    PubMed Central

    Brette, Romain

    2012-01-01

    Neurons communicate primarily with spikes, but most theories of neural computation are based on firing rates. Yet, many experimental observations suggest that the temporal coordination of spikes plays a role in sensory processing. Among potential spike-based codes, synchrony appears as a good candidate because neural firing and plasticity are sensitive to fine input correlations. However, it is unclear what role synchrony may play in neural computation, and what functional advantage it may provide. With a theoretical approach, I show that the computational interest of neural synchrony appears when neurons have heterogeneous properties. In this context, the relationship between stimuli and neural synchrony is captured by the concept of synchrony receptive field, the set of stimuli which induce synchronous responses in a group of neurons. In a heterogeneous neural population, it appears that synchrony patterns represent structure or sensory invariants in stimuli, which can then be detected by postsynaptic neurons. The required neural circuitry can spontaneously emerge with spike-timing-dependent plasticity. Using examples in different sensory modalities, I show that this allows simple neural circuits to extract relevant information from realistic sensory stimuli, for example to identify a fluctuating odor in the presence of distractors. This theory of synchrony-based computation shows that relative spike timing may indeed have computational relevance, and suggests new types of neural network models for sensory processing with appealing computational properties. PMID:22719243

  18. A consensual neural network

    NASA Technical Reports Server (NTRS)

    Benediktsson, J. A.; Ersoy, O. K.; Swain, P. H.

    1991-01-01

    A neural network architecture called a consensual neural network (CNN) is proposed for the classification of data from multiple sources. Its relation to hierarchical and ensemble neural networks is discussed. CNN is based on the statistical consensus theory and uses nonlinearly transformed input data. The input data are transformed several times, and the different transformed data are applied as if they were independent inputs. The independent inputs are classified using stage neural networks and outputs from the stage networks are then weighted and combined to make a decision. Experimental results based on remote-sensing data and geographic data are given.

  19. To proliferate or to die: role of Id3 in cell cycle progression and survival of neural crest progenitors

    PubMed Central

    Kee, Yun; Bronner-Fraser, Marianne

    2005-01-01

    The neural crest is a unique population of mitotically active, multipotent progenitors that arise at the vertebrate neural plate border. Here, we show that the helix-loop-helix transcriptional regulator Id3 has a novel role in cell cycle progression and survival of neural crest progenitors in Xenopus. Id3 is localized at the neural plate border during gastrulation and neurulation, overlapping the domain of neural crest induction. Morpholino oligonucleotide-mediated depletion of Id3 results in the absence of neural crest precursors and a resultant loss of neural crest derivatives. This appears to be mediated by cell cycle inhibition followed by cell death of the neural crest progenitor pool, rather than a cell fate switch. Conversely, overexpression of Id3 increases cell proliferation and results in expansion of the neural crest domain. Our data suggest that Id3 functions by a novel mechanism, independent of cell fate determination, to mediate the decision of neural crest precursors to proliferate or die. PMID:15769946

  20. Characterization of the genomic structure of the mouse APLP1 gene

    SciTech Connect

    Zhong, Sue; Wu, Kuo; Black, I.B.; Schaar, D.G.

    1996-02-15

    This article reports on the organization of the mouse APLP1 gene, an evolutionarily conserved amyloid precursor-like protein. The amyloid beta protein, important in Alzheimer diseases, is derived from these precursor proteins. By investigating the expression and structure of this murine gene, it is hoped that more will be learned about the function and regulation of the human homologue. 27 refs., 2 figs.

  1. What Are Neural Tube Defects?

    MedlinePlus

    ... NICHD Research Information Clinical Trials Resources and Publications Neural Tube Defects (NTDs): Condition Information Skip sharing on ... media links Share this: Page Content What are neural tube defects? Neural (pronounced NOOR-uhl ) tube defects ...

  2. Ancestral network module regulating prdm1 expression in the lamprey neural plate border

    PubMed Central

    Nikitina, Natalya; Tong, Leslie; Bronner-Fraser, Marianne

    2012-01-01

    prdm1 is an important transcriptional regulator that plays diverse roles during development of a wide variety of vertebrate and invertebrate species. prdm1 is required for neural crest specification in zebrafish, but not in mouse embryos. The role of this gene in neural crest formation in other species has not been examined, and its regulation during embryonic development is poorly understood. Here, we investigate the expression pattern, function and the upstream regulatory inputs into prdm1 during lamprey neural crest development. prdm1 is strongly expressed in the lamprey neural plate border, suggesting a conserved ancestral role of this gene in the neural crest formation. We found that lamprey neural plate border expression of prdm1 is activated by Ap-2 and Msx, but is independent of Pax3/7 and Zic. PMID:21932309

  3. Inhibition of APP gamma-secretase restores Sonic Hedgehog signaling and neurogenesis in the Ts65Dn mouse model of Down syndrome

    PubMed Central

    Giacomini, Andrea; Stagni, Fiorenza; Trazzi, Stefania; Guidi, Sandra; Emili, Marco; Brigham, Elizabeth; Ciani, Elisabetta; Bartesaghi, Renata

    2015-01-01

    Neurogenesis impairment starting from early developmental stages is a key determinant of intellectual disability in Down syndrome (DS). Previous evidence provided a causal relationship between neurogenesis impairment and malfunctioning of the mitogenic Sonic Hedgehog (Shh) pathway. In particular, excessive levels of AICD (amyloid precursor protein intracellular domain), a cleavage product of the trisomic gene APP (amyloid precursor protein) up-regulate transcription of Ptch1 (Patched1), the Shh receptor that keeps the pathway repressed. Since AICD results from APP cleavage by γ-secretase, the goal of the cur