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Sample records for lineage-restricted neuronal progenitor

  1. In Vivo Clonal Analysis Reveals Lineage-Restricted Progenitor Characteristics in Mammalian Kidney Development, Maintenance, and Regeneration

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    Yuval Rinkevich

    2014-05-01

    Full Text Available The mechanism and magnitude by which the mammalian kidney generates and maintains its proximal tubules, distal tubules, and collecting ducts remain controversial. Here, we use long-term in vivo genetic lineage tracing and clonal analysis of individual cells from kidneys undergoing development, maintenance, and regeneration. We show that the adult mammalian kidney undergoes continuous tubulogenesis via expansions of fate-restricted clones. Kidneys recovering from damage undergo tubulogenesis through expansions of clones with segment-specific borders, and renal spheres developing in vitro from individual cells maintain distinct, segment-specific fates. Analysis of mice derived by transfer of color-marked embryonic stem cells (ESCs into uncolored blastocysts demonstrates that nephrons are polyclonal, developing from expansions of singly fated clones. Finally, we show that adult renal clones are derived from Wnt-responsive precursors, and their tracing in vivo generates tubules that are segment specific. Collectively, these analyses demonstrate that fate-restricted precursors functioning as unipotent progenitors continuously maintain and self-preserve the mouse kidney throughout life.

  2. Heterogeneity in the developmental potential of motor neuron progenitors revealed by clonal analysis of single cells in vitro

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    Schieren Ira

    2009-01-01

    Full Text Available Abstract Background The differentiation of neural progenitors into distinct classes within the central nervous system occurs over an extended period during which cells become progressively restricted in their fates. In the developing spinal cord, Sonic Hedgehog (Shh controls neural fates in a concentration-dependent manner by establishing discrete ventral progenitor domains characterized by specific combinations of transcription factors. It is unclear whether motor neuron progenitors can maintain their identities when expanded in vitro and whether their developmental potentials are restricted when exposed to defined extracellular signals. Results We have generated mice expressing the enhanced green fluorescent protein under the control of the Nkx6.1 promoter, enabling fluorescence-activated cell sorting (FACS, purification and culture of individual spinal progenitors at clonal density, and analysis of their progeny. We demonstrate that cells isolated after progenitor domains are established are heterogeneous with respect to maintaining their identity after in vitro expansion. Most Nkx6.1+ progenitors lose their ventral identity following several divisions in culture, whereas a small subset is able to maintain its identity. Thus, subtype-restricted progenitors from the Nkx6.1+ region are present in the ventral spinal cord, although at a lower frequency than expected. Clones that maintain a motor neuron identity assume a transcriptional profile characteristic of thoracic motor neurons, despite some having been isolated from non-thoracic regions initially. Exposure of progenitors to Bone Morphogenetic Protein-4 induces some dorsal cell type characteristics in their progeny, revealing that lineage-restricted progenitor subtypes are not fully committed to their fates. Conclusion These findings support a model whereby continuous Shh signaling is required to maintain the identity of ventral progenitors isolated from the spinal cord, including motor

  3. Transplanted progenitors generate functional enteric neurons in the postnatal colon

    OpenAIRE

    2013-01-01

    Cell therapy has the potential to treat gastrointestinal motility disorders caused by diseases of the enteric nervous system. Many studies have demonstrated that various stem/progenitor cells can give rise to functional neurons in the embryonic gut; however, it is not yet known whether transplanted neural progenitor cells can migrate, proliferate, and generate functional neurons in the postnatal bowel in vivo. We transplanted neurospheres generated from fetal and postnatal intestinal neural c...

  4. Transplanted progenitors generate functional enteric neurons in the postnatal colon

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    Hotta, Ryo; Stamp, Lincon A.; Foong, Jaime P.P.; McConnell, Sophie N.; Bergner, Annette J.; Anderson, Richard B.; Enomoto, Hideki; Newgreen, Donald F.; Obermayr, Florian; Furness, John B.; Young, Heather M.

    2013-01-01

    Cell therapy has the potential to treat gastrointestinal motility disorders caused by diseases of the enteric nervous system. Many studies have demonstrated that various stem/progenitor cells can give rise to functional neurons in the embryonic gut; however, it is not yet known whether transplanted neural progenitor cells can migrate, proliferate, and generate functional neurons in the postnatal bowel in vivo. We transplanted neurospheres generated from fetal and postnatal intestinal neural crest–derived cells into the colon of postnatal mice. The neurosphere-derived cells migrated, proliferated, and generated neurons and glial cells that formed ganglion-like clusters within the recipient colon. Graft-derived neurons exhibited morphological, neurochemical, and electrophysiological characteristics similar to those of enteric neurons; they received synaptic inputs; and their neurites projected to muscle layers and the enteric ganglia of the recipient mice. These findings show that transplanted enteric neural progenitor cells can generate functional enteric neurons in the postnatal bowel and advances the notion that cell therapy is a promising strategy for enteric neuropathies. PMID:23454768

  5. Specification of excitatory neurons in the developing cerebral cortex: progenitor diversity and and environmental influences

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    Marcos R Costa

    2015-01-01

    Full Text Available The mature cerebral cortex harbors a heterogeneous population of glutamatergic neurons, organized into a highly intricate histological architecture. Classically, this mixed population of neurons was thought to be generated sequentially from a seemingly homogenous group of progenitors under the influence of external cues. This view, however, has been challenged in the last decade by evidences pointing to the existence of fate-restricted neuronal progenitors in the developing neocortex. Here, we review classical studies using cell transplantation, retroviral labeling and cell culture, as well as new data from genetic fate-mapping analysis, to discuss the lineage relationships between neocortical progenitors and subclasses of excitatory neurons. We also propose a temporal model to conciliate the existence of fate-restricted progenitors alongside multipotent progenitors in the neocortex. Finally, we discuss evidences for a critical period of plasticity among post mitotic excitatory cortical neurons when environmental influences could change neuronal cell fate.

  6. Human motor neuron progenitor transplantation leads to endogenous neuronal sparing in 3 models of motor neuron loss.

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    Wyatt, Tanya J; Rossi, Sharyn L; Siegenthaler, Monica M; Frame, Jennifer; Robles, Rockelle; Nistor, Gabriel; Keirstead, Hans S

    2011-01-01

    Motor neuron loss is characteristic of many neurodegenerative disorders and results in rapid loss of muscle control, paralysis, and eventual death in severe cases. In order to investigate the neurotrophic effects of a motor neuron lineage graft, we transplanted human embryonic stem cell-derived motor neuron progenitors (hMNPs) and examined their histopathological effect in three animal models of motor neuron loss. Specifically, we transplanted hMNPs into rodent models of SMA (Δ7SMN), ALS (SOD1 G93A), and spinal cord injury (SCI). The transplanted cells survived and differentiated in all models. In addition, we have also found that hMNPs secrete physiologically active growth factors in vivo, including NGF and NT-3, which significantly enhanced the number of spared endogenous neurons in all three animal models. The ability to maintain dying motor neurons by delivering motor neuron-specific neurotrophic support represents a powerful treatment strategy for diseases characterized by motor neuron loss.

  7. Motor neurons and oligodendrocytes arise from distinct cell lineages by progenitor recruitment.

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    Ravanelli, Andrew M; Appel, Bruce

    2015-12-01

    During spinal cord development, ventral neural progenitor cells that express the transcription factors Olig1 and Olig2, called pMN progenitors, produce motor neurons and then oligodendrocytes. Whether motor neurons and oligodendrocytes arise from common or distinct progenitors in vivo is not known. Using zebrafish, we found that motor neurons and oligodendrocytes are produced sequentially by distinct progenitors that have distinct origins. When olig2(+) cells were tracked during the peak period of motor neuron formation, most differentiated as motor neurons without further cell division. Using time-lapse imaging, we found that, as motor neurons differentiated, more dorsally positioned neuroepithelial progenitors descended to the pMN domain and initiated olig2 expression. Inhibition of Hedgehog signaling during motor neuron differentiation blocked the ventral movement of progenitors, the progressive initiation of olig2 expression, and oligodendrocyte formation. We therefore propose that the motor neuron-to-oligodendrocyte switch results from Hedgehog-mediated recruitment of glial-fated progenitors to the pMN domain subsequent to neurogenesis.

  8. Neural Progenitor Cells Derived from Human Embryonic Stem Cells as an Origin of Dopaminergic Neurons

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    Parinya Noisa

    2015-01-01

    Full Text Available Human embryonic stem cells (hESCs are able to proliferate in vitro indefinitely without losing their ability to differentiate into multiple cell types upon exposure to appropriate signals. Particularly, the ability of hESCs to differentiate into neuronal subtypes is fundamental to develop cell-based therapies for several neurodegenerative disorders, such as Alzheimer’s disease, Huntington’s disease, and Parkinson’s disease. In this study, we differentiated hESCs to dopaminergic neurons via an intermediate stage, neural progenitor cells (NPCs. hESCs were induced to neural progenitor cells by Dorsomorphin, a small molecule that inhibits BMP signalling. The resulting neural progenitor cells exhibited neural bipolarity with high expression of neural progenitor genes and possessed multipotential differentiation ability. CBF1 and bFGF responsiveness of these hES-NP cells suggested their similarity to embryonic neural progenitor cells. A substantial number of dopaminergic neurons were derived from hES-NP cells upon supplementation of FGF8 and SHH, key dopaminergic neuron inducers. Importantly, multiple markers of midbrain neurons were detected, including NURR1, PITX3, and EN1, suggesting that hESC-derived dopaminergic neurons attained the midbrain identity. Altogether, this work underscored the generation of neural progenitor cells that retain the properties of embryonic neural progenitor cells. These cells will serve as an unlimited source for the derivation of dopaminergic neurons, which might be applicable for treating patients with Parkinson’s disease.

  9. Molecular markers of neuronal progenitors in the embryonic cerebellar anlage.

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    Morales, Daniver; Hatten, Mary E

    2006-11-22

    The cerebellum, like the cerebrum, includes a nuclear structure and an overlying cortical structure. Experiments in the past decade have expanded knowledge beyond the traditional function of the cerebellum to include critical roles in motor learning and memory and sensory discrimination. The initial steps in cerebellar development depend on inductive signaling involving FGF and Wnt proteins produced at the mesencephalic/metencephalic boundary. To address the issue of how individual cerebellar cell fates within the cerebellar territory are specified, we examined the expression of transcription factors, including mammalian homologues of LIM homeodomain-containing proteins, basic helix-loop-helix proteins, and three amino acid loop-containing proteins. The results of these studies show that combinatorial codes of transcription factors define precursors of the cerebellar nuclei, and both Purkinje cells and granule neurons of the cerebellar cortex. Examination of gene expression patterns in several hundred lines of Egfp-BAC (bacterial artificial chromosome) transgenic mice in the GENSAT Project revealed numerous genes with restricted expression in cerebellar progenitor populations, including genes specific for cerebellar nuclear precursors and Purkinje cell precursors. In addition, we identified patterns of gene expression that link granule and Purkinje cells to their precerebellar nuclei. These results identify molecular pathways that offer new insights on the development of the nuclear and cortical structures of the cerebellum, as well as components of the cerebellar circuitry.

  10. Human Motor Neuron Progenitor Transplantation Leads to Endogenous Neuronal Sparing in 3 Models of Motor Neuron Loss

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    Tanya J. Wyatt

    2011-01-01

    Full Text Available Motor neuron loss is characteristic of many neurodegenerative disorders and results in rapid loss of muscle control, paralysis, and eventual death in severe cases. In order to investigate the neurotrophic effects of a motor neuron lineage graft, we transplanted human embryonic stem cell-derived motor neuron progenitors (hMNPs and examined their histopathological effect in three animal models of motor neuron loss. Specifically, we transplanted hMNPs into rodent models of SMA (Δ7SMN, ALS (SOD1 G93A, and spinal cord injury (SCI. The transplanted cells survived and differentiated in all models. In addition, we have also found that hMNPs secrete physiologically active growth factors in vivo, including NGF and NT-3, which significantly enhanced the number of spared endogenous neurons in all three animal models. The ability to maintain dying motor neurons by delivering motor neuron-specific neurotrophic support represents a powerful treatment strategy for diseases characterized by motor neuron loss.

  11. Effect of matrix composition on differentiation of nestin-positive neural progenitors from circulation into neurons

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    Jose, Anumol; Krishnan, Lissy K.

    2010-06-01

    The human peripheral blood mononuclear cell has a mixture of progenitor cells with potential to differentiate into a wide range of lineages. The ability of hematopoietic tissue-derived adult stem cells to differentiate into neural progenitor cells offers an alternative to embryonic stem cells as a viable source for cell transplantation therapies to cure neurodegenerative diseases. This approach could lead to the use of autologous progenitors from blood circulation; however, due to the limited numbers available, in vitro cell expansion may be indispensable. In addition, for successful transplantation there is the requirement of a delivery matrix on which cells can survive and differentiate. In this context we carried out this study to identify a suitable biodegradable matrix on which progenitor cells can home, multiply and differentiate. We designed different compositions of the biomimetic matrix containing fibrin, fibronectin, gelatin, growth factors, laminin and hyaluronic acid. The attached cells expressed proliferation markers in initial periods of culture and between days 6 and 9 in culture they differentiated into neurons and/or astrocytes. The differentiation of progenitors into neurons and asterocyte on the composed matrix was established by morphological and immunochemical analysis. Flow cytometric analysis of cells in culture was employed to track development of neurons which expressed an early marker β-tubulin3 and a terminal marker microtubule-associated protein-2 at a later culture period. In vitro experiments indicate that a highly specific niche consisting of various components of the extracellular matrix, including hyaluronic acid, promote cell homing, survival and differentiation.

  12. Histological and functional benefit following transplantation of motor neuron progenitors to the injured rat spinal cord.

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    Sharyn L Rossi

    Full Text Available BACKGROUND: Motor neuron loss is characteristic of cervical spinal cord injury (SCI and contributes to functional deficit. METHODOLOGY/PRINCIPAL FINDINGS: In order to investigate the amenability of the injured adult spinal cord to motor neuron differentiation, we transplanted spinal cord injured animals with a high purity population of human motor neuron progenitors (hMNP derived from human embryonic stem cells (hESCs. In vitro, hMNPs displayed characteristic motor neuron-specific markers, a typical electrophysiological profile, functionally innervated human or rodent muscle, and secreted physiologically active growth factors that caused neurite branching and neuronal survival. hMNP transplantation into cervical SCI sites in adult rats resulted in suppression of intracellular signaling pathways associated with SCI pathogenesis, which correlated with greater endogenous neuronal survival and neurite branching. These neurotrophic effects were accompanied by significantly enhanced performance on all parameters of the balance beam task, as compared to controls. Interestingly, hMNP transplantation resulted in survival, differentiation, and site-specific integration of hMNPs distal to the SCI site within ventral horns, but hMNPs near the SCI site reverted to a neuronal progenitor state, suggesting an environmental deficiency for neuronal maturation associated with SCI. CONCLUSIONS/SIGNIFICANCE: These findings underscore the barriers imposed on neuronal differentiation of transplanted cells by the gliogenic nature of the injured spinal cord, and the physiological relevance of transplant-derived neurotrophic support to functional recovery.

  13. Apoptotic neurons induce proliferative responses of progenitor cells in the postnatal neocortex.

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    Petrenko, Volodymyr; Mihhailova, Jevgenia; Salmon, Patrick; Kiss, Jozsef Z

    2015-11-01

    Apoptotic cell death is the leading cause of neuronal loss after neonatal brain injury. Little is known about the intrinsic capacity of the immature cerebral cortex for replacing dead cells. Here we test the hypothesis that neuronal apoptosis is able to trigger compensatory proliferation in surrounding cells. In order to establish a "pure" apoptotic cell death model and to avoid the confounding effects of broken blood-brain barrier and inflammatory reactions, we used a diphtheria toxin (DT) and diphtheria toxin receptor (DTR) system to induce ablation of layer IV neurons in the rodent somatosensory cortex during the early postnatal period. We found that DT-triggered apoptosis is a slowly progressing event lasting about for 7 days. While dying cells expressed the morphological features of apoptosis, we could not detect immunoreactivity for activated caspase-3 in these cells. Microglia activation and proliferation represented the earliest cellular responses to apoptotic cell death. In addition, we found that induced apoptosis triggered a massive proliferation of undifferentiated progenitor cell pool including Sox2 as well as NG2 cells. The default differentiation pattern of proliferating progenitors appears to be the glial phenotype; we could not find evidence for newly generated neurons in response to apoptotic neuronal death. These results suggest that mitotically active progenitor populations are intrinsically capable to contribute to the repair process of injured cortical tissue and may represent a potential target for neuronal replacement strategies.

  14. Dual roles of lineage restricted transcription factors: the case of MITF in melanocytes.

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    Levy, Carmit; Fisher, David E

    2011-01-01

    Microphthalmia-associated Transcription Factor, MITF, is a master regulator of melanocyte development, differentiation, migration, and survival.(1) A broad collection of studies have indicated that MITF directly regulates the transcription of genes involved in pigmentation, which are selective to the melanocyte lineage. In addition, MITF controls expression of genes which are expressed in multiple cell lineages, and may also play differential roles in activating vs. maintaining gene expression patterns. In this Point of View article, we discuss lineage restricted transcription factor activation of both tissue-specific and ubiquitously expressed genes using melanocytes and MITF as a model system that may eventually provide insights into such processes in multiple cell lineages.

  15. Regulation of progenitor cell proliferation and neuronal differentiation in enteric nervous system neurospheres.

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    Sokratis Theocharatos

    Full Text Available Enteric nervous system (ENS progenitor cells isolated from mouse and human bowel can be cultured in vitro as neurospheres which are aggregates of the proliferating progenitor cells, together with neurons and glial cells derived from them. To investigate the factors regulating progenitor cell proliferation and differentiation, we first characterised cell proliferation in mouse ENS neurospheres by pulse chase experiments using thymidine analogs. We demonstrate rapid and continuous cell proliferation near the neurosphere periphery, after which postmitotic cells move away from the periphery to become distributed throughout the neurosphere. While many proliferating cells expressed glial markers, expression of the neuronal markers β-tubulin III (Tuj1 and nitric oxide synthase was detected in increasing numbers of post-mitotic cells after a delay of several days. Treatment of both mouse and human neurospheres with the γ-secretase inhibitor N-[N-(3,5-Difluorophenacetyl-L-alanyl]-S-phenylglycine t-butyl ester (DAPT reduced expression of the transcription factors Hes1 and Hes5, demonstrating inhibition of Notch signaling. DAPT treatment also inhibited progenitor cell proliferation and increased the numbers of differentiating neurons expressing Tuj1 and nitric oxide synthase. To confirm that the cellular effects of DAPT treatment were due to inhibition of Notch signaling, siRNA knockdown of RBPjκ, a key component of the canonical Notch signaling pathway, was demonstrated both to reduce proliferation and to increase neuronal differentiation in neurosphere cells. These observations indicate that Notch signaling promotes progenitor cell proliferation and inhibits neuronal differentiation in ENS neurospheres.

  16. Derivation of high purity neuronal progenitors from human embryonic stem cells.

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    Gabriel Nistor

    Full Text Available The availability of human neuronal progenitors (hNPs in high purity would greatly facilitate neuronal drug discovery and developmental studies, as well as cell replacement strategies for neurodegenerative diseases and conditions, such as spinal cord injury, stroke, Parkinson's disease, Alzheimer's disease, and Huntington's disease. Here we describe for the first time a method for producing hNPs in large quantity and high purity from human embryonic stem cells (hESCs in feeder-free conditions, without the use of exogenous noggin, sonic hedgehog or analogs, rendering the process clinically compliant. The resulting population displays characteristic neuronal-specific markers. When allowed to spontaneously differentiate into neuronal subtypes in vitro, cholinergic, serotonergic, dopaminergic and/or noradrenergic, and medium spiny striatal neurons were observed. When transplanted into the injured spinal cord the hNPs survived, integrated into host tissue, and matured into a variety of neuronal subtypes. Our method of deriving neuronal progenitors from hESCs renders the process amenable to therapeutic and commercial use.

  17. Adult c-Kit(+) progenitor cells are necessary for maintenance and regeneration of olfactory neurons.

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    Goldstein, Bradley J; Goss, Garrett M; Hatzistergos, Konstantinos E; Rangel, Erika B; Seidler, Barbara; Saur, Dieter; Hare, Joshua M

    2015-01-01

    The olfactory epithelium houses chemosensory neurons, which transmit odor information from the nose to the brain. In adult mammals, the olfactory epithelium is a uniquely robust neuroproliferative zone, with the ability to replenish its neuronal and non-neuronal populations due to the presence of germinal basal cells. The stem and progenitor cells of these germinal layers, and their regulatory mechanisms, remain incompletely defined. Here we show that progenitor cells expressing c-Kit, a receptor tyrosine kinase marking stem cells in a variety of embryonic tissues, are required for maintenance of the adult neuroepithelium. Mouse genetic fate-mapping analyses show that embryonically, a c-Kit(+) population contributes to olfactory neurogenesis. In adults under conditions of normal turnover, there is relatively sparse c-Kit(+) progenitor cell (ckPC) activity. However, after experimentally induced neuroepithelial injury, ckPCs are activated such that they reconstitute the neuronal population. There are also occasional non-neuronal cells found to arise from ckPCs. Moreover, the selective depletion of the ckPC population, utilizing temporally controlled targeted diphtheria toxin A expression, results in failure of neurogenesis after experimental injury. Analysis of this model indicates that most ckPCs reside among the globose basal cell populations and act downstream of horizontal basal cells, which can serve as stem cells. Identification of the requirement for olfactory c-Kit-expressing progenitors in olfactory maintenance provides new insight into the mechanisms involved in adult olfactory neurogenesis. Additionally, we define an important and previously unrecognized site of adult c-Kit activity.

  18. Zebrafish Müller glia-derived progenitors are multipotent, exhibit proliferative biases and regenerate excess neurons

    National Research Council Canada - National Science Library

    Powell, Curtis; Cornblath, Eli; Elsaeidi, Fairouz; Wan, Jin; Goldman, Daniel

    2016-01-01

    ...) that respond to injury by reprogramming and adopting retinal stem cell properties. These reprogrammed MG divide to produce a proliferating population of retinal progenitors that migrate to areas of retinal damage and regenerate lost neurons...

  19. Neurodevelopment. Parasympathetic neurons originate from nerve-associated peripheral glial progenitors.

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    Dyachuk, Vyacheslav; Furlan, Alessandro; Shahidi, Maryam Khatibi; Giovenco, Marcela; Kaukua, Nina; Konstantinidou, Chrysoula; Pachnis, Vassilis; Memic, Fatima; Marklund, Ulrika; Müller, Thomas; Birchmeier, Carmen; Fried, Kaj; Ernfors, Patrik; Adameyko, Igor

    2014-07-04

    The peripheral autonomic nervous system reaches far throughout the body and includes neurons of diverse functions, such as sympathetic and parasympathetic. We show that the parasympathetic system in mice--including trunk ganglia and the cranial ciliary, pterygopalatine, lingual, submandibular, and otic ganglia--arise from glial cells in nerves, not neural crest cells. The parasympathetic fate is induced in nerve-associated Schwann cell precursors at distal peripheral sites. We used multicolor Cre-reporter lineage tracing to show that most of these neurons arise from bi-potent progenitors that generate both glia and neurons. This nerve origin places cellular elements for generating parasympathetic neurons in diverse tissues and organs, which may enable wiring of the developing parasympathetic nervous system.

  20. Late-stage neuronal progenitors in the retina are radial Müller glia that function as retinal stem cells.

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    Bernardos, Rebecca L; Barthel, Linda K; Meyers, Jason R; Raymond, Pamela A

    2007-06-27

    Neuronal progenitors in the mammalian brain derive from radial glia or specialized astrocytes. In developing neural retina, radial glia-like Müller cells are generated late in neurogenesis and are not considered to be neuronal progenitors, but they do proliferate after injury and can express neuronal markers, suggesting a latent neurogenic capacity. To examine the neurogenic capacity of retinal glial cells, we used lineage tracing in transgenic zebrafish with a glial-specific promoter (gfap, for glial fibrillary acid protein) driving green fluorescent protein in differentiated Müller glia. We found that all Müller glia in the zebrafish retina express low levels of the multipotent progenitor marker Pax6 (paired box gene 6), and they proliferate at a low frequency in the intact, uninjured retina. Müller glia-derived progenitors express Crx (cone rod homeobox) and are late retinal progenitors that generate the rod photoreceptor lineage in the postembryonic retina. These Müller glia-derived progenitors also remain competent to produce earlier neuronal lineages, in that they respond to loss of cone photoreceptors by specifically regenerating the missing neurons. We conclude that zebrafish Müller glia function as multipotent retinal stem cells that generate retinal neurons by homeostatic and regenerative developmental mechanisms.

  1. Live imaging at the onset of cortical neurogenesis reveals differential appearance of the neuronal phenotype in apical versus basal progenitor progeny.

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    Alessio Attardo

    Full Text Available The neurons of the mammalian brain are generated by progenitors dividing either at the apical surface of the ventricular zone (neuroepithelial and radial glial cells, collectively referred to as apical progenitors or at its basal side (basal progenitors, also called intermediate progenitors. For apical progenitors, the orientation of the cleavage plane relative to their apical-basal axis is thought to be of critical importance for the fate of the daughter cells. For basal progenitors, the relationship between cell polarity, cleavage plane orientation and the fate of daughter cells is unknown. Here, we have investigated these issues at the very onset of cortical neurogenesis. To directly observe the generation of neurons from apical and basal progenitors, we established a novel transgenic mouse line in which membrane GFP is expressed from the beta-III-tubulin promoter, an early pan-neuronal marker, and crossed this line with a previously described knock-in line in which nuclear GFP is expressed from the Tis21 promoter, a pan-neurogenic progenitor marker. Mitotic Tis21-positive basal progenitors nearly always divided symmetrically, generating two neurons, but, in contrast to symmetrically dividing apical progenitors, lacked apical-basal polarity and showed a nearly randomized cleavage plane orientation. Moreover, the appearance of beta-III-tubulin-driven GFP fluorescence in basal progenitor-derived neurons, in contrast to that in apical progenitor-derived neurons, was so rapid that it suggested the initiation of the neuronal phenotype already in the progenitor. Our observations imply that (i the loss of apical-basal polarity restricts neuronal progenitors to the symmetric mode of cell division, and that (ii basal progenitors initiate the expression of neuronal phenotype already before mitosis, in contrast to apical progenitors.

  2. Development of Cortical GABAergic Neurons: Interplay of progenitor diversity and environmental factors on fate specification

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    Juliana Alves Brandão

    2015-04-01

    Full Text Available Cortical GABAergic interneurons constitute an extremely diverse population of cells organized in a well-defined topology of precisely interconnected cells. They play a crucial role regulating inhibitory-excitatory balance in brain circuits, gating sensory perception and regulating spike timing to brain oscillations during distinct behaviors. Dysfunctions in the establishment of proper inhibitory circuits have been associated to several brain disorders such as autism, epilepsy and schizophrenia. In the rodent adult cortex, inhibitory neurons are generated during the second gestational week from distinct progenitor lineages located in restricted domains of the ventral telencephalon. However, only recently, studies have revealed some of the mechanisms generating the heterogeneity of neuronal subtypes and their modes of integration in brain networks. Here we will discuss some the events involved in the production of cortical GABAergic neuron diversity with focus on the interaction between intrinsically driven genetic programs and environmental signals during development.

  3. Human primordial germ cell-derived progenitors give rise to neurons and glia in vivo

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    Teng, Yincheng [Department of Gynecology and Obstetrics, The 6th People' s Hospital, School of Medicine, Shanghai Jiao Tong University, 600 Yishan Road, Shanghai 200233 (China); Chen, Bin [Center for Developmental Biology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, 1665 Kong Jiang Road, Shanghai 200092 (China); Tao, Minfang, E-mail: Taomf@126.com [Department of Gynecology and Obstetrics, The 6th People' s Hospital, School of Medicine, Shanghai Jiao Tong University, 600 Yishan Road, Shanghai 200233 (China)

    2009-12-18

    We derived a cell population from cultured human primordial germ cells from early human embryos. The derivates, termed embryoid body-derived (EBD) cells, displayed an extensive capacity for proliferation and expressed a panel of markers in all three germ layers. Interestingly, EBD cells were also positive for markers of neural stem/progenitor cells, such as nestin and glial fibrillary acidic protein. When these cells were transplanted into the brain cavities of fetal sheep and postnatal NOD-SCID mice or nerve-degenerated tibialis anterior muscles, they readily gave rise to neurons or glial cells. To our knowledge, our data are the first to demonstrate that EBD cells can undergo further neurogenesis under suitable environments in vivo. Hence, with the abilities of extensive expansion, self-renewal, and differentiation, EBD cells may provide a useful donor source for neural stem/progenitor cells to be used in cell-replacement therapies for diseases of the nervous system.

  4. Rapid Ngn2-induction of excitatory neurons from hiPSC-derived neural progenitor cells

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    Ho, Seok-Man; Hartley, Brigham J.; Julia, TCW; Beaumont, Michael; Stafford, Khalifa; Slesinger, Paul A.; Brennand, Kristen J.

    2015-01-01

    Since the discovery of somatic reprogramming, human induced pluripotent stem cells (hiPSCs) have been exploited to model a variety of neurological and psychiatric disorders. Because hiPSCs represent an almost limitless source of patient-derived neurons that retain the genetic variations thought to contribute to disease etiology, they have been heralded as a patient-specific platform for high throughput drug screening. However, the utility of current protocols for generating neurons from hiPSCs remains limited by protracted differentiation timelines and heterogeneity of the neuronal phenotypes produced. Neuronal induction via the forced expression of exogenous transcription factors rapidly induces defined populations of functional neurons from fibroblasts and hiPSCs. Here, we describe an adapted protocol that accelerates maturation of functional excitatory neurons from hiPSC-derived neural progenitor cells (NPCs) via lentiviral transduction of Neurogenin 2 (using both mNgn2 and hNGN2). This methodology, relying upon a robust and scalable starting population of hiPSC NPCs, should be readily amenable to scaling for hiPSC-based high-throughput drug screening. PMID:26626326

  5. Neural Progenitor Cells Promote Axonal Growth and Alter Axonal mRNA Localization in Adult Neurons

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    Merianda, Tanuja T.; Jin, Ying

    2017-01-01

    Abstract The inhibitory environment of the spinal cord and the intrinsic properties of neurons prevent regeneration of axons following CNS injury. However, both ascending and descending axons of the injured spinal cord have been shown to regenerate into grafts of embryonic neural progenitor cells (NPCs). Previous studies have shown that grafts composed of glial-restricted progenitors (GRPs) and neural-restricted progenitors (NRPs) can provide a permissive microenvironment for axon growth. We have used cocultures of adult rat dorsal root ganglion (DRG) neurons together with NPCs, which have shown significant enhancement of axon growth by embryonic rat GRP and GRPs/NRPs, both in coculture conditions and when DRGs are exposed to conditioned medium from the NPC cultures. This growth-promoting effect of NPC-conditioned medium was also seen in injury-conditioned neurons. DRGs cocultured with GRPs/NRPs showed altered expression of regeneration-associated genes at transcriptional and post-transcriptional levels. We found that levels of GAP-43 mRNA increased in DRG cell bodies and axons. However, hepcidin antimicrobial peptide (HAMP) mRNA decreased in the cell bodies of DRGs cocultured with GRPs/NRPs, which is distinct from the increase in cell body HAMP mRNA levels seen in DRGs after injury conditioning. Endogenous GAP-43 and β-actin mRNAs as well as reporter RNAs carrying axonally localizing 3'UTRs of these transcripts showed significantly increased levels in distal axons in the DRGs cocultured with GRPs/NRPs. These results indicate that axon growth promoted by NPCs is associated not only with enhanced transcription of growth-associated genes but also can increase localization of some mRNAs into growing axons. PMID:28197547

  6. Neural Progenitor Cells Promote Axonal Growth and Alter Axonal mRNA Localization in Adult Neurons.

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    Merianda, Tanuja T; Jin, Ying; Kalinski, Ashley L; Sahoo, Pabitra K; Fischer, Itzhak; Twiss, Jeffery L

    2017-01-01

    The inhibitory environment of the spinal cord and the intrinsic properties of neurons prevent regeneration of axons following CNS injury. However, both ascending and descending axons of the injured spinal cord have been shown to regenerate into grafts of embryonic neural progenitor cells (NPCs). Previous studies have shown that grafts composed of glial-restricted progenitors (GRPs) and neural-restricted progenitors (NRPs) can provide a permissive microenvironment for axon growth. We have used cocultures of adult rat dorsal root ganglion (DRG) neurons together with NPCs, which have shown significant enhancement of axon growth by embryonic rat GRP and GRPs/NRPs, both in coculture conditions and when DRGs are exposed to conditioned medium from the NPC cultures. This growth-promoting effect of NPC-conditioned medium was also seen in injury-conditioned neurons. DRGs cocultured with GRPs/NRPs showed altered expression of regeneration-associated genes at transcriptional and post-transcriptional levels. We found that levels of GAP-43 mRNA increased in DRG cell bodies and axons. However, hepcidin antimicrobial peptide (HAMP) mRNA decreased in the cell bodies of DRGs cocultured with GRPs/NRPs, which is distinct from the increase in cell body HAMP mRNA levels seen in DRGs after injury conditioning. Endogenous GAP-43 and β-actin mRNAs as well as reporter RNAs carrying axonally localizing 3'UTRs of these transcripts showed significantly increased levels in distal axons in the DRGs cocultured with GRPs/NRPs. These results indicate that axon growth promoted by NPCs is associated not only with enhanced transcription of growth-associated genes but also can increase localization of some mRNAs into growing axons.

  7. Asymmetric cell division of granule neuron progenitors in the external granule layer of the mouse cerebellum

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    Parthiv Haldipur; Iswariya Sivaprakasam; Vinod Periasamy; Subashika Govindan; Shyamala Mani

    2015-01-01

    ABSTRACT The plane of division of granule neuron progenitors (GNPs) was analysed with respect to the pial surface in P0 to P14 cerebellum and the results showed that there was a significant bias towards the plane of cell division being parallel to pial surface across this developmental window. In addition, the distribution of β-Catenin in anaphase cells was analysed, which showed that there was a significant asymmetry in the distribution of β-Catenin in dividing GNPs. Further, inhibition of S...

  8. Asymmetric cell division of granule neuron progenitors in the external granule layer of the mouse cerebellum.

    Science.gov (United States)

    Haldipur, Parthiv; Sivaprakasam, Iswariya; Periasamy, Vinod; Govindan, Subashika; Mani, Shyamala

    2015-05-15

    The plane of division of granule neuron progenitors (GNPs) was analysed with respect to the pial surface in P0 to P14 cerebellum and the results showed that there was a significant bias towards the plane of cell division being parallel to pial surface across this developmental window. In addition, the distribution of β-Catenin in anaphase cells was analysed, which showed that there was a significant asymmetry in the distribution of β-Catenin in dividing GNPs. Further, inhibition of Sonic Hedgehog (Shh) signalling had an effect on plane of cell division. Asymmetric distribution of β-Catenin was shown to occur towards the source of a localized extracellular cue.

  9. A self-renewing division of zebrafish Müller glial cells generates neuronal progenitors that require N-cadherin to regenerate retinal neurons.

    Science.gov (United States)

    Nagashima, Mikiko; Barthel, Linda K; Raymond, Pamela A

    2013-11-01

    Müller glia function as retinal stem cells in adult zebrafish. In response to loss of retinal neurons, Müller glia partially dedifferentiate, re-express neuroepithelial markers and re-enter the cell cycle. We show that the immunoglobulin superfamily adhesion molecule Alcama is a novel marker of multipotent retinal stem cells, including injury-induced Müller glia, and that each Müller glial cell divides asymmetrically only once to produce an Alcama-negative, proliferating retinal progenitor. The initial mitotic division of Müller glia involves interkinetic nuclear migration, but mitosis of retinal progenitors occurs in situ. Rapidly dividing retinal progenitors form neurogenic clusters tightly associated with Alcama/N-cadherin-labeled Müller glial radial processes. Genetic suppression of N-cadherin function interferes with basal migration of retinal progenitors and subsequent regeneration of HuC/D(+) inner retinal neurons.

  10. Regulation of primary spinal neuron lineages after deletion of a major progenitor.

    Science.gov (United States)

    Gallagher, Betty C; Moody, Sally A

    2004-09-01

    Vertebrate embryos are able to reconstitute the body plan when early blastomeres are deleted, but it is not known whether this is accomplished by cells local to the lesion or by a readjustment of the entire pattern of the embryo. We distinguished between these two possibilities by studying which embryonic cells change primary spinal neuronal fates after deletion of a major spinal cord progenitor. After ablation of the V1.2 blastomere of the 16-cell Xenopus embryo, the spinal cord contained normal numbers of Rohon-Beard neurons and primary motoneurons, indicating that the remaining blastomeres numerically reconstituted these populations. Using lineage-tracing techniques we revealed a global response: 10 out of the 15 remaining blastomeres significantly changed the number of one or both neuronal types they produced. This widespread response indicates that position in the early embryo plays an important role in regulating the production of primary spinal neurons. However, not all cells are influenced solely by position; a vegetal cell transplanted into the position of the deleted V1.2 did not take on the neuronal fate of its new position. Thus, restitution of pattern relies on a combination of positional cues and intrinsic fate restrictions. Copyright 2004 Elsevier SAS

  11. Zebrafish Müller glia-derived progenitors are multipotent, exhibit proliferative biases and regenerate excess neurons

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    Curtis Powell; Eli Cornblath; Fairouz Elsaeidi; Jin Wan; Daniel Goldman

    2016-01-01

    Unlike mammals, zebrafish can regenerate a damaged retina. Key to this regenerative response are Müller glia (MG) that respond to injury by reprogramming and adopting retinal stem cell properties. These reprogrammed MG divide to produce a proliferating population of retinal progenitors that migrate to areas of retinal damage and regenerate lost neurons. Previous studies have suggested that MG-derived progenitors may be biased to produce that are lost with injury. Here we investigated MG multi...

  12. Direct lineage reprogramming of mouse fibroblasts to functional midbrain dopaminergic neuronal progenitors

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    Han-Seop Kim

    2014-01-01

    Full Text Available The direct lineage reprogramming of somatic cells to other lineages by defined factors has led to innovative cell-fate-change approaches for providing patient-specific cells. Recent reports have demonstrated that four pluripotency factors (Oct4, Sox2, Klf4, and c-Myc are sufficient to directly reprogram fibroblasts to other specific cells, including induced neural stem cells (iNSCs. Here, we show that mouse fibroblasts can be directly reprogrammed into midbrain dopaminergic neuronal progenitors (DPs by temporal expression of the pluripotency factors and environment containing sonic hedgehog and fibroblast growth factor 8. Within thirteen days, self-renewing and functional induced DPs (iDPs were generated. Interestingly, the inhibition of both Jak and Gsk3β notably enhanced the iDP reprogramming efficiency. We confirmed the functionality of the iDPs by showing that the dopaminergic neurons generated from iDPs express midbrain markers, release dopamine, and show typical electrophysiological profiles. Our results demonstrate that the pluripotency factors-mediated direct reprogramming is an invaluable strategy for supplying functional and proliferating iDPs and may be useful for other neural progenitors required for disease modeling and cell therapies for neurodegenerative disorders.

  13. Dynamic Expression Patterns of Progenitor and Pyramidal Neuron Layer Markers in the Developing Human Hippocampus.

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    Cipriani, Sara; Nardelli, Jeannette; Verney, Catherine; Delezoide, Anne-Lise; Guimiot, Fabien; Gressens, Pierre; Adle-Biassette, Homa

    2016-03-01

    The molecular mechanisms underlying the formation of hippocampus are unknown in humans. To improve our knowledge of molecules that potentially regulate pyramidal neurogenesis and layering in various hippocampal fields, we investigated the expression of progenitor markers and cell fate molecules from gestational week (GW) 9 to GW 20. At GW 9, the progenitor cell compartment of the hippocampal formation mainly consisted of PAX6(+) cells in the ventricular zone. Between GW 9 and 11, a second germinal area, the subventricular zone (SVZ), was formed, as shown by TBR2 labeling. Postmitotic markers (TBR1, CTIP2, SATB2, and CUX1) might reflect the inside-out layering of the plate from GW 11 onwards. TBR1(+) neurons appeared in the deep plate, whereas CTIP2(+), SATB2(+), and CUX1(+) neurons occupied the upper layers. From GW 16, differences in layer segregation were observed between the ammonic and subicular plates. Moreover, an ammonic-to-subicular maturation gradient was observed in germinal/postmitotic areas. Taken together, these findings demonstrate for the first time the presence of an SVZ in the hippocampus of human fetuses and laminar differences in transcription factor expression in the pyramidal layer of the human ammonic and subicular plate, and provide new information to further investigate the connectivity of the hippocampal formation.

  14. Zebrafish Müller glia-derived progenitors are multipotent, exhibit proliferative biases and regenerate excess neurons.

    Science.gov (United States)

    Powell, Curtis; Cornblath, Eli; Elsaeidi, Fairouz; Wan, Jin; Goldman, Daniel

    2016-04-20

    Unlike mammals, zebrafish can regenerate a damaged retina. Key to this regenerative response are Müller glia (MG) that respond to injury by reprogramming and adopting retinal stem cell properties. These reprogrammed MG divide to produce a proliferating population of retinal progenitors that migrate to areas of retinal damage and regenerate lost neurons. Previous studies have suggested that MG-derived progenitors may be biased to produce that are lost with injury. Here we investigated MG multipotency using injury paradigms that target different retinal nuclear layers for cell ablation. Our data indicate that regardless of which nuclear layer was damaged, MG respond by generating multipotent progenitors that migrate to all nuclear layers and differentiate into layer-specific cell types, suggesting that MG-derived progenitors in the injured retina are intrinsically multipotent. However, our analysis of progenitor proliferation reveals a proliferative advantage in nuclear layers where neurons were ablated. This suggests that feedback inhibition from surviving neurons may skew neuronal regeneration towards ablated cell types.

  15. In vivo clonal analysis reveals lineage-restricted progenitor characteristics in mammalian kidney development, maintenance, and regeneration

    NARCIS (Netherlands)

    Rinkevich, Y.; Montoro, D.T.; Contreras-Trujillo, H.; Harari-Steinberg, O.; Newman, A.M.; Tsai, J.M.; Lim, X.; van Amerongen, R.; Bowman, A.; Januszyk, M.; Pleniceanu, O.; Nusse, R.; Longaker, M.T.; Weissman, I.L.; Dekel, B.

    2014-01-01

    The mechanism and magnitude by which the mammalian kidney generates and maintains its proximal tubules, distal tubules, and collecting ducts remain controversial. Here, we use long-term in vivo genetic lineage tracing and clonal analysis of individual cells from kidneys undergoing development, maint

  16. Lingo-1 shRNA and Notch signaling inhibitor DAPT promote differentiation of neural stem/progenitor cells into neurons.

    Science.gov (United States)

    Wang, Jue; Ye, Zhizhong; Zheng, Shuhui; Chen, Luming; Wan, Yong; Deng, Yubin; Yang, Ruirui

    2016-03-01

    Determination of the exogenous factors that regulate differentiation of neural stem/progenitor cells into neurons, oligodendrocytes and astrocytes is an important step in the clinical therapy of spinal cord injury (SCI). The Notch pathway inhibits the differentiation of neural stem/progenitor cells and Lingo-1 is a strong negative regulator for myelination and axon growth. While Lingo-1 shRNA and N-[N-(3, 5-difluorophenacetyl)-1-alanyl]-S-Phenylglycinet-butylester (DAPT), a Notch pathway inhibitor, have been used separately to help repair SCI, the results have been unsatisfactory. Here we investigated and elucidated the preliminary mechanism for the effect of Lingo-1 shRNA and DAPT on neural stem/progenitor cells differentiation. We found that neural stem/progenitor cells from E14 rat embryos expressed Nestin, Sox-2 and Lingo-1, and we optimized the transduction of neural stem/progenitor cells using lentiviral vectors encoding Lingo-1 shRNA. The addition of DAPT decreased the expression of Notch intracellular domain (NICD) as well as the downstream genes Hes1 and Hes5. Expression of NeuN, CNPase and GFAP in DAPT treated cells and expression of NeuN in Lingo-1 shRNA treated cells confirmed differentiation of neural stem/progenitor cells into neurons, oligodendrocytes and astrocytes. These results revealed that while Lingo-1 shRNA and Notch signaling inhibitor DAPT both promoted differentiation of neural stem cells into neurons, only DAPT was capable of driving neural stem/progenitor cells differentiation into oligodendrocytes and astrocytes. Since we were able to show that both Lingo-1 shRNA and DAPT could drive neural stem/progenitor cells differentiation, our data might aid the development of more effective SCI therapies using Lingo-1 shRNA and DAPT.

  17. Prenatal exposure of ethanol induces increased glutamatergic neuronal differentiation of neural progenitor cells

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    Han Seol-Heui

    2010-11-01

    Full Text Available Abstract Background Prenatal ethanol exposure during pregnancy induces a spectrum of mental and physical disorders called fetal alcohol spectrum disorder (FASD. The central nervous system is the main organ influenced by FASD, and neurological symptoms include mental retardation, learning abnormalities, hyperactivity and seizure susceptibility in childhood along with the microcephaly. In this study, we examined whether ethanol exposure adversely affects the proliferation of NPC and de-regulates the normal ratio between glutamatergic and GABAergic neuronal differentiation using primary neural progenitor culture (NPC and in vivo FASD models. Methods Neural progenitor cells were cultured from E14 embryo brain of Sprague-Dawley rat. Pregnant mice and rats were treated with ethanol (2 or 4 g/kg/day diluted with normal saline from E7 to E16 for in vivo FASD animal models. Expression level of proteins was investigated by western blot analysis and immunocytochemical assays. MTT was used for cell viability. Proliferative activity of NPCs was identified by BrdU incorporation, immunocytochemistry and FACS analysis. Results Reduced proliferation of NPCs by ethanol was demonstrated using BrdU incorporation, immunocytochemistry and FACS analysis. In addition, ethanol induced the imbalance between glutamatergic and GABAergic neuronal differentiation via transient increase in the expression of Pax6, Ngn2 and NeuroD with concomitant decrease in the expression of Mash1. Similar pattern of expression of those transcription factors was observed using an in vivo model of FASD as well as the increased expression of PSD-95 and decreased expression of GAD67. Conclusions These results suggest that ethanol induces hyper-differentiation of glutamatergic neuron through Pax6 pathway, which may underlie the hyper-excitability phenotype such as hyperactivity or seizure susceptibility in FASD patients.

  18. Dynamic Expression Patterns of Progenitor and Neuron Layer Markers in the Developing Human Dentate Gyrus and Fimbria.

    Science.gov (United States)

    Cipriani, Sara; Journiac, Nathalie; Nardelli, Jeannette; Verney, Catherine; Delezoide, Anne-Lise; Guimiot, Fabien; Gressens, Pierre; Adle-Biassette, Homa

    2017-01-01

    The molecular mechanisms that orchestrate the development of the human dentate gyrus are not known. In this study, we characterized the formation of human dentate and fimbrial progenitors and postmitotic neurons from 9 gestational weeks (GW9) to GW25. PAX6+ progenitor cells remained proliferative until GW16 in the dentate ventricular zone. By GW11, the secondary dentate matrix had developed in the intermediate zone, surrounding the dentate anlage and streaming toward the subpial layer. This secondary matrix contained proliferating PAX6+ and/or TBR2+ progenitors. In parallel, SOX2+ and PAX6+ fimbrial cells were detected approaching the dentate anlage, representing a possible source of extra-dentate progenitors. By GW16, when the granule cell layer could be delineated, a hilar matrix containing PAX6+ and some TBR2+ progenitors had become identifiable. By GW25, when the 2 limbs of the granule cell layer had formed, the secondary dentate matrix was reduced to a pool of progenitors at the fimbrio-dentate junction. Although human dentate development recapitulates key steps previously described in rodents, differences seemed to emerge in neuron layer markers expression. Further studies are necessary to better elucidate their role in dentate formation and connectivity. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  19. Possible promotion of neuronal differentiation in fetal rat brain neural progenitor cells after sustained exposure to static magnetism.

    Science.gov (United States)

    Nakamichi, Noritaka; Ishioka, Yukichi; Hirai, Takao; Ozawa, Shusuke; Tachibana, Masaki; Nakamura, Nobuhiro; Takarada, Takeshi; Yoneda, Yukio

    2009-08-15

    We have previously shown significant potentiation of Ca(2+) influx mediated by N-methyl-D-aspartate receptors, along with decreased microtubules-associated protein-2 (MAP2) expression, in hippocampal neurons cultured under static magnetism without cell death. In this study, we investigated the effects of static magnetism on the functionality of neural progenitor cells endowed to proliferate for self-replication and differentiate into neuronal, astroglial, and oligodendroglial lineages. Neural progenitor cells were isolated from embryonic rat neocortex and hippocampus, followed by culture under static magnetism at 100 mT and subsequent determination of the number of cells immunoreactive for a marker protein of particular progeny lineages. Static magnetism not only significantly decreased proliferation of neural progenitor cells without affecting cell viability, but also promoted differentiation into cells immunoreactive for MAP2 with a concomitant decrease in that for an astroglial marker, irrespective of the presence of differentiation inducers. In neural progenitors cultured under static magnetism, a significant increase was seen in mRNA expression of several activator-type proneural genes, such as Mash1, Math1, and Math3, together with decreased mRNA expression of the repressor type Hes5. These results suggest that sustained static magnetism could suppress proliferation for self-renewal and facilitate differentiation into neurons through promoted expression of activator-type proneural genes by progenitor cells in fetal rat brain.

  20. Promoted neuronal differentiation after activation of alpha4/beta2 nicotinic acetylcholine receptors in undifferentiated neural progenitors.

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    Takeshi Takarada

    Full Text Available BACKGROUND: Neural progenitor is a generic term used for undifferentiated cell populations of neural stem, neuronal progenitor and glial progenitor cells with abilities for proliferation and differentiation. We have shown functional expression of ionotropic N-methyl-D-aspartate (NMDA and gamma-aminobutyrate type-A receptors endowed to positively and negatively regulate subsequent neuronal differentiation in undifferentiated neural progenitors, respectively. In this study, we attempted to evaluate the possible functional expression of nicotinic acetylcholine receptor (nAChR by undifferentiated neural progenitors prepared from neocortex of embryonic rodent brains. METHODOLOGY/PRINCIPAL FINDINGS: Reverse transcription polymerase chain reaction analysis revealed mRNA expression of particular nAChR subunits in undifferentiated rat and mouse progenitors prepared before and after the culture with epidermal growth factor under floating conditions. Sustained exposure to nicotine significantly inhibited the formation of neurospheres composed of clustered proliferating cells and 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide reduction activity at a concentration range of 1 µM to 1 mM without affecting cell survival. In these rodent progenitors previously exposed to nicotine, marked promotion was invariably seen for subsequent differentiation into cells immunoreactive for a neuronal marker protein following the culture of dispersed cells under adherent conditions. Both effects of nicotine were significantly prevented by the heteromeric α4β2 nAChR subtype antagonists dihydro-β-erythroidine and 4-(5-ethoxy-3-pyridinyl-N-methyl-(3E-3-buten-1-amine, but not by the homomeric α7 nAChR subtype antagonist methyllycaconitine, in murine progenitors. Sustained exposure to nicotine preferentially increased the expression of Math1 among different basic helix-loop-helix proneural genes examined. In undifferentiated progenitors from embryonic mice

  1. Asymmetric cell division of granule neuron progenitors in the external granule layer of the mouse cerebellum

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    Parthiv Haldipur

    2015-07-01

    Full Text Available The plane of division of granule neuron progenitors (GNPs was analysed with respect to the pial surface in P0 to P14 cerebellum and the results showed that there was a significant bias towards the plane of cell division being parallel to pial surface across this developmental window. In addition, the distribution of β-Catenin in anaphase cells was analysed, which showed that there was a significant asymmetry in the distribution of β-Catenin in dividing GNPs. Further, inhibition of Sonic Hedgehog (Shh signalling had an effect on plane of cell division. Asymmetric distribution of β-Catenin was shown to occur towards the source of a localized extracellular cue.

  2. MiR-34a represses Numbl in murine neural progenitor cells and antagonizes neuronal differentiation.

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    Sarah K Fineberg

    Full Text Available MicroRNA (miRNA function is required for normal animal development, in particular in differentiation pathways from stem cell and precursor populations. In neurogenesis, it is becoming increasingly appreciated that miRNAs act at many stages to ensure proper progression. In this study we examined the role of miR-34a in neural progenitor cells (NPC derived from murine embryonic cortex. We found that over-expression of miR-34a in NPC significantly reduced the neuron yield upon in vitro induction of differentiation. MiR-34a has several predicted targets in the Notch pathway, which operates to balance progenitor self-renewal and differentiation during cortical neurogenesis. We tested several Notch pathway players for regulation by miR-34a in undifferentiated NPC, and found that mRNA and protein levels of Numbl, a negative regulator of Notch signaling, as well as two downstream pro-neural genes usually blocked by Notch signaling, NeuroD1 and Mash1, were diminished, while Notch1 and Cbf1 transcripts were enhanced by miR-34a over-expression. Using a luciferase reporter assay, we verified the Numbl 3'-UTR as a direct miR-34a target. Correspondingly, knock-down of endogenous miR-34a resulted in increased Numbl, NeuroD1 and Mash1, and reduced Notch1 transcript levels. Together these results implicate Numbl as a physiologically relevant target of miR-34a in NPC, allowing for enhanced Notch signaling and inhibition of neuronal differentiation. This work extends our understanding of miR-34a-mediated control of cell differentiation from cancer to mammalian nervous system development.

  3. Bone marrow mesenchymal stem cells stimulate proliferation and neuronal differentiation of retinal progenitor cells.

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    Jing Xia

    Full Text Available During retina development, retinal progenitor cell (RPC proliferation and differentiation are regulated by complex inter- and intracellular interactions. Bone marrow mesenchymal stem cells (BMSCs are reported to express a variety of cytokines and neurotrophic factors, which have powerful trophic and protective functions for neural tissue-derived cells. Here, we show that the expanded RPC cultures treated with BMSC-derived conditioned medium (CM which was substantially enriched for bFGF and CNTF, expressed clearly increased levels of nuclear receptor TLX, an essential regulator of neural stem cell (NSC self-renewal, as well as betacellulin (BTC, an EGF-like protein described as supporting NSC expansion. The BMSC CM- or bFGF-treated RPCs also displayed an obviously enhanced proliferation capability, while BMSC CM-derived bFGF knocked down by anti-bFGF, the effect of BMSC CM on enhancing RPC proliferation was partly reversed. Under differentiation conditions, treatment with BMSC CM or CNTF markedly favoured RPC differentiation towards retinal neurons, including Brn3a-positive retinal ganglion cells (RGCs and rhodopsin-positive photoreceptors, and clearly diminished retinal glial cell differentiation. These findings demonstrate that BMSCs supported RPC proliferation and neuronal differentiation which may be partly mediated by BMSC CM-derived bFGF and CNTF, reveal potential limitations of RPC culture systems, and suggest a means for optimizing RPC cell fate determination in vitro.

  4. Time-lapse imaging reveals symmetric neurogenic cell division of GFAP-expressing progenitors for expansion of postnatal dentate granule neurons.

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    Takashi Namba

    Full Text Available Granule cells in the hippocampus, a region critical for memory and learning, are generated mainly during the early postnatal period but neurogenesis continues in adulthood. Postnatal neuronal production is carried out by primary progenitors that express glial fibrillary acidic protein (GFAP and they are assumed to function as stem cells. A central question regarding postnatal dentate neurogenesis is how astrocyte-like progenitors produce neurons. To reveal cell division patterns and the process of neuronal differentiation of astrocyte-like neural progenitors, we performed time-lapse imaging in cultured hippocampal slices from early postnatal transgenic mice with mouse GFAP promoter-controlled enhanced green fluorescent protein (mGFAP-eGFP Tg mice in combination with a retrovirus carrying a red fluorescent protein gene. Our results showed that the majority of GFAP-eGFP+ progenitor cells that express GFAP, Sox2 and nestin divided symmetrically to produce pairs of GFAP+ cells (45% or pairs of neuron-committed cells (45%, whereas a minority divided asymmetrically to generate GFAP+ cells and neuron-committed cells (10%. The present results suggest that a substantial number of GFAP-expressing progenitors functions as transient amplifying progenitors, at least in an early postnatal dentate gyrus, although a small population appears to be stem cell-like progenitors. From the present data, we discuss possible cell division patterns of adult GFAP+ progenitors.

  5. Time-lapse imaging reveals symmetric neurogenic cell division of GFAP-expressing progenitors for expansion of postnatal dentate granule neurons.

    Science.gov (United States)

    Namba, Takashi; Mochizuki, Hideki; Suzuki, Ryusuke; Onodera, Masafumi; Yamaguchi, Masahiro; Namiki, Hideo; Shioda, Seiji; Seki, Tatsunori

    2011-01-01

    Granule cells in the hippocampus, a region critical for memory and learning, are generated mainly during the early postnatal period but neurogenesis continues in adulthood. Postnatal neuronal production is carried out by primary progenitors that express glial fibrillary acidic protein (GFAP) and they are assumed to function as stem cells. A central question regarding postnatal dentate neurogenesis is how astrocyte-like progenitors produce neurons. To reveal cell division patterns and the process of neuronal differentiation of astrocyte-like neural progenitors, we performed time-lapse imaging in cultured hippocampal slices from early postnatal transgenic mice with mouse GFAP promoter-controlled enhanced green fluorescent protein (mGFAP-eGFP Tg mice) in combination with a retrovirus carrying a red fluorescent protein gene. Our results showed that the majority of GFAP-eGFP+ progenitor cells that express GFAP, Sox2 and nestin divided symmetrically to produce pairs of GFAP+ cells (45%) or pairs of neuron-committed cells (45%), whereas a minority divided asymmetrically to generate GFAP+ cells and neuron-committed cells (10%). The present results suggest that a substantial number of GFAP-expressing progenitors functions as transient amplifying progenitors, at least in an early postnatal dentate gyrus, although a small population appears to be stem cell-like progenitors. From the present data, we discuss possible cell division patterns of adult GFAP+ progenitors.

  6. Engrafted Neural Stem/Progenitor Cells Promote Functional Recovery through Synapse Reorganization with Spared Host Neurons after Spinal Cord Injury

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    Kazuya Yokota

    2015-08-01

    Full Text Available Neural stem/progenitor cell (NSPC transplantation is a promising therapeutic strategy for spinal cord injury (SCI. However, the efficacy of NSPC transplantation on severe SCI is poorly understood. We herein show that NSPC transplantation promotes functional recovery after mild and moderate SCI, but not after severe SCI. In severe SCI mice, there were few remaining host neurons within the range of NSPC engraftment; thus, we examined whether the co-distribution of transplant and host is a contributory factor for functional improvement. A cellular selective analysis using laser microdissection revealed that drug-induced host neuronal ablation considerably decreased the synaptogenic potential of the engrafted NSPCs. Furthermore, following host neuronal ablation, neuronal retrograde tracing showed less propriospinal relay connections bridging the lesion after NSPC transplantation. Our findings suggest that the interactive synaptic reorganization between engrafted NSPCs and spared host neurons is crucial for functional recovery, providing significant insight for establishing therapeutic strategies for severe SCI.

  7. Generation of neuronal progenitor cells in response to tumors in the human brain.

    Science.gov (United States)

    Macas, Jadranka; Ku, Min-Chi; Nern, Christian; Xu, Yuanzhi; Bühler, Helmut; Remke, Marc; Synowitz, Michael; Franz, Kea; Seifert, Volker; Plate, Karl H; Kettenmann, Helmut; Glass, Rainer; Momma, Stefan

    2014-01-01

    Data from transgenic mouse models show that neuronal progenitor cells (NPCs) migrate toward experimental brain tumors and modulate the course of pathology. However, the pathways whereby NPCs are attracted to CNS neoplasms are not fully understood and it is unexplored if NPCs migrate toward brain tumors (high-grade astrocytomas) in humans. We analyzed the tumor-parenchyma interface of neurosurgical resections for the presence of (NPCs) and distinguished these physiological cells from the tumor mass. We observed that polysialic acid neural cell adhesion molecule-positive NPCs accumulate at the border of high-grade astrocytomas and display a marker profile consistent with immature migratory NPCs. Importantly, these high-grade astrocytoma-associated NPCs did not carry genetic aberrations that are indicative of the tumor. Additionally, we observed NPCs accumulating in CNS metastases. These metastatic tumors are distinguished from neural cells by defined sets of markers. Transplanting murine glioma cells embedded in a cell-impermeable hollow fiber capsule into the brains of nestin-gfp reporter mice showed that diffusible factors are sufficient to induce a neurogenic reaction. In vitro, vascular endothelial growth factor (VEGF) secreted from glioma cells increases the migratory and proliferative behavior of adult human brain-derived neural stem and progenitor cells via stimulation of VEGF receptor-2 (VEGFR-2). In vivo, inhibiting VEGFR-2 signaling with a function-blocking antibody led to a reduction in NPC migration toward tumors. Overall, our data reveal a mechanism by which NPCs are attracted to CNS tumors and suggest that NPCs accumulate in human high-grade astrocytomas.

  8. Geminin loss causes neural tube defects through disrupted progenitor specification and neuronal differentiation.

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    Patterson, Ethan S; Waller, Laura E; Kroll, Kristen L

    2014-09-01

    Geminin is a nucleoprotein that can directly bind chromatin regulatory complexes to modulate gene expression during development. Geminin knockout mouse embryos are preimplantation lethal by the 32-cell stage, precluding in vivo study of Geminin's role in neural development. Therefore, here we used a conditional Geminin allele in combination with several Cre-driver lines to define an essential role for Geminin during mammalian neural tube (NT) formation and patterning. Geminin was required in the NT within a critical developmental time window (embryonic day 8.5-10.5), when NT patterning and closure occurs. Geminin excision at these stages resulted in strongly diminished expression of genes that mark and promote dorsal NT identities and decreased differentiation of ventral motor neurons, resulting in completely penetrant NT defects, while excision after embryonic day 10.5 did not result in NT defects. When Geminin was deleted specifically in the spinal NT, both NT defects and axial skeleton defects were observed, but neither defect occurred when Geminin was excised in paraxial mesenchyme, indicating a tissue autonomous requirement for Geminin in developing neuroectoderm. Despite a potential role for Geminin in cell cycle control, we found no evidence of proliferation defects or altered apoptosis. Comparisons of gene expression in the NT of Geminin mutant versus wild-type siblings at embryonic day 10.5 revealed decreased expression of key regulators of neurogenesis, including neurogenic bHLH transcription factors and dorsal interneuron progenitor markers. Together, these data demonstrate a requirement for Geminin for NT patterning and neuronal differentiation during mammalian neurulation in vivo.

  9. Bradykinin promotes neuron-generating division of neural progenitor cells through ERK activation.

    Science.gov (United States)

    Pillat, Micheli M; Lameu, Claudiana; Trujillo, Cleber A; Glaser, Talita; Cappellari, Angélica R; Negraes, Priscilla D; Battastini, Ana M O; Schwindt, Telma T; Muotri, Alysson R; Ulrich, Henning

    2016-09-15

    During brain development, cells proliferate, migrate and differentiate in highly accurate patterns. In this context, published results indicate that bradykinin functions in neural fate determination, favoring neurogenesis and migration. However, mechanisms underlying bradykinin function are yet to be explored. Our findings indicate a previously unidentified role for bradykinin action in inducing neuron-generating division in vitro and in vivo, given that bradykinin lengthened the G1-phase of the neural progenitor cells (NPC) cycle and increased TIS21 (also known as PC3 and BTG2) expression in hippocampus from newborn mice. This role, triggered by activation of the kinin-B2 receptor, was conditioned by ERK1/2 activation. Moreover, immunohistochemistry analysis of hippocampal dentate gyrus showed that the percentage of Ki67(+) cells markedly increased in bradykinin-treated mice, and ERK1/2 inhibition affected this neurogenic response. The progress of neurogenesis depended on sustained ERK phosphorylation and resulted in ERK1/2 translocation to the nucleus in NPCs and PC12 cells, changing expression of genes such as Hes1 and Ngn2 (also known as Neurog2). In agreement with the function of ERK in integrating signaling pathways, effects of bradykinin in stimulating neurogenesis were reversed following removal of protein kinase C (PKC)-mediated sustained phosphorylation.

  10. Intermediate Progenitor Cohorts Differentially Generate Cortical Layers and Require Tbr2 for Timely Acquisition of Neuronal Subtype Identity.

    Science.gov (United States)

    Mihalas, Anca B; Elsen, Gina E; Bedogni, Francesco; Daza, Ray A M; Ramos-Laguna, Kevyn A; Arnold, Sebastian J; Hevner, Robert F

    2016-06-28

    Intermediate progenitors (IPs) amplify the production of pyramidal neurons, but their role in selective genesis of cortical layers or neuronal subtypes remains unclear. Using genetic lineage tracing in mice, we find that IPs destined to produce upper cortical layers first appear early in corticogenesis, by embryonic day 11.5. During later corticogenesis, IP laminar fates are progressively limited to upper layers. We examined the role of Tbr2, an IP-specific transcription factor, in laminar fate regulation using Tbr2 conditional mutant mice. Upon Tbr2 inactivation, fewer neurons were produced by immediate differentiation and laminar fates were shifted upward. Genesis of subventricular mitoses was, however, not reduced in the context of a Tbr2-null cortex. Instead, neuronal and laminar differentiation were disrupted and delayed. Our findings indicate that upper-layer genesis depends on IPs from many stages of corticogenesis and that Tbr2 regulates the tempo of laminar fate implementation for all cortical layers.

  11. Intermediate Progenitor Cohorts Differentially Generate Cortical Layers and Require Tbr2 for Timely Acquisition of Neuronal Subtype Identity

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    Anca B. Mihalas

    2016-06-01

    Full Text Available Intermediate progenitors (IPs amplify the production of pyramidal neurons, but their role in selective genesis of cortical layers or neuronal subtypes remains unclear. Using genetic lineage tracing in mice, we find that IPs destined to produce upper cortical layers first appear early in corticogenesis, by embryonic day 11.5. During later corticogenesis, IP laminar fates are progressively limited to upper layers. We examined the role of Tbr2, an IP-specific transcription factor, in laminar fate regulation using Tbr2 conditional mutant mice. Upon Tbr2 inactivation, fewer neurons were produced by immediate differentiation and laminar fates were shifted upward. Genesis of subventricular mitoses was, however, not reduced in the context of a Tbr2-null cortex. Instead, neuronal and laminar differentiation were disrupted and delayed. Our findings indicate that upper-layer genesis depends on IPs from many stages of corticogenesis and that Tbr2 regulates the tempo of laminar fate implementation for all cortical layers.

  12. ADAM17 is critical for multipolar exit and radial migration of neuronal intermediate progenitor cells in mice cerebral cortex.

    Science.gov (United States)

    Li, Qingyu; Zhang, Zhengyu; Li, Zengmin; Zhou, Mei; Liu, Bin; Pan, Le; Ma, Zhixing; Zheng, Yufang

    2013-01-01

    The radial migration of neuronal progenitor cells is critical for the development of cerebral cortex layers. They go through a critical step transforming from multipolar to bipolar before outward migration. A Disintegrin and Metalloprotease 17 (ADAM17) is a transmembrane protease which can process many substrates involved in cell-cell interaction, including Notch, ligands of EGFR, and some cell adhesion molecules. In this study, we used in utero electroporation to knock down or overexpress ADAM17 at embryonic day 14.5 (E14.5) in neuronal progenitor cells to examine the role of ADAM17 in cortical embryonic neurogenesis. Our results showed that the radial migration of ADAM17-knocked down cells were normal till E16.5 and reached the intermediate zone (IZ). Then most transfected cells stopped migration and stayed at the IZ to inner cortical plate (CP) layer at E18.5, and there was higher percentage of multipolar cells at IZ layer in the ADAM17-knocked down group compared to the cells in control group. Marker staining revealed that those ADAM17-knocked down cells differentiated normally from neural stem cells (NSCs) to neuronal intermediate progenitor cells (nIPCs) but did not differentiate into mature neurons. The migration and multipolar exit defects caused by ADAM17 knockdown could be partially rescued by over-expressing an shRNA resistant ADAM17, while overexpressing ADAM17 alone did not affect the radial migration. Taken together, our results showed for the first time that, ADAM17 is critical in regulating the multipolar-stage exit and radial migration of the nIPCs during telencephalon cortex development in mice.

  13. Arctic ground squirrel neuronal progenitor cells resist oxygen and glucose deprivation-induced death

    Science.gov (United States)

    Drew, Kelly L; Wells, Matthew; McGee, Rebecca; Ross, Austin P; Kelleher-Andersson, Judith

    2016-01-01

    AIM: To investigate the influence of ischemia/reperfusion on arctic ground squirrel (AGS) neuronal progenitor cells (NPCs), we subjected these cultured cells to oxygen and glucose deprivation. METHODS: AGS NPCs were expanded and differentiated into NPCs and as an ischemia vulnerable control, commercially available human NPCs (hNPCs) were seeded from thawed NPCs. NPCs, identified by expression of TUJ1 were seen at 14-21 d in vitro (DIV). Cultures were exposed to control conditions, hypoxia, oxygen and glucose deprivation or glucose deprivation alone or following return to normal conditions to model reperfusion. Cell viability and death were assessed from loss of ATP as well as from measures of alamarBlue® and lactate dehydrogenase in the media and from counts of TUJ1 positive cells using immunocytochemistry. Dividing cells were identified by expression of Ki67 and phenotyped by double labeling with GFAP, MAP2ab or TUJ1. RESULTS: We report that when cultured in NeuraLife™, AGS cells remain viable out to 21 DIV, continue to express TUJ1 and begin to express MAP2ab. Viability of hNPCs assessed by fluorescence alamarBlue (arbitrary units) depends on both glucose and oxygen availability [viability of hNPCs after 24 h oxygen glucose deprivation (OGD) with return of oxygen and glucose decreased from 48151 ± 4551 in control cultures to 43481 ± 2413 after OGD, P < 0.05]. By contrast, when AGS NPCs are exposed to the same OGD with reperfusion at 14 DIV, cell viability assessed by alamarBlue increased from 165305 ± 11719 in control cultures to 196054 ± 13977 after OGD. Likewise AGS NPCs recovered ATP (92766 ± 6089 in control and 92907 ± 4290 after modeled reperfusion; arbitrary luminescence units), and doubled in the ratio of TUJ1 expressing neurons to total dividing cells (0.11 ± 0.04 in control cultures vs 0.22 ± 0.2 after modeled reperfusion, P < 0.05). Maintaining AGS NPCs for a longer time in culture lowered resistance to injury, however, did not impair

  14. Arctic ground squirrel neuronal progenitor cells resist oxygen and glucose deprivation-induced death

    Institute of Scientific and Technical Information of China (English)

    Kelly L Drew; Matthew Wells; Rebecca McGee; Austin P Ross; Judith Kelleher-Andersson

    2016-01-01

    AIM: To investigate the influence of ischemia/reperfusion on arctic ground squirrel(AGS) neuronal progenitor cells(NPCs), we subjected these cultured cells to oxygen and glucose deprivation.METHODS: AGS NPCs were expanded and differentiated into NPCs and as an ischemia vulnerable control, commercially available human NPCs(hNPCs) were seeded from thawed NPCs. NPCs, identified by expression of TUJ1 were seen at 14-21 d in vitro(DIV). Cultures were exposed to control conditions, hypoxia, oxygen and glucose deprivation or glucose deprivation alone or following return to normal conditions to model reperfusion. Cell viability and death were assessed from loss of ATP as well as from measures of alamarB lue and lactate dehydrogenase in the media and from counts of TUJ1 positive cells using immunocytochemistry. Dividing cells were identified by expression of Ki67 and phenotyped by double labeling with GFAP, MAP2 ab or TUJ1. RESULTS: We report that when cultured in NeuraLifeTM, AGS cells remain viable out to 21 DIV, continue to express TUJ1 and begin to express MAP2 ab. Viability of hN PCs assessed by fluorescence alamarB lue(arbitrary units) depends on both glucose and oxygen availability [viability of hNPCs after 24 h oxygen glucose deprivation(OGD) with return of oxygen and glucose decreased from 48151 ± 4551 in control cultures to 43481 ± 2413 after OGD, P < 0.05]. By contrast, when AGS NPCs are exposed to the same OGD with reperfusion at 14 DIV, cell viability assessed by alamar Blue increased from 165305 ± 11719 in control cultures to 196054 ± 13977 after OGD. Likewise AGS NPCs recovered ATP(92766 ± 6089 in control and 92907 ± 4290 after modeled reperfusion; arbitrary luminescence units), and doubled in the ratio of TUJ1 expressing neurons to total dividing cells(0.11 ± 0.04 in control cultures vs 0.22 ± 0.2 after modeled reperfusion, P < 0.05). Maintaining AGS NPCs for a longer time in culture lowered resistance to injury

  15. Integrating microRNA and mRNA expression profiles of neuronal progenitors to identify regulatory networks underlying the onset of cortical neurogenesis

    Directory of Open Access Journals (Sweden)

    Barker Jeffery L

    2009-08-01

    Full Text Available Abstract Background Cortical development is a complex process that includes sequential generation of neuronal progenitors, which proliferate and migrate to form the stratified layers of the developing cortex. To identify the individual microRNAs (miRNAs and mRNAs that may regulate the genetic network guiding the earliest phase of cortical development, the expression profiles of rat neuronal progenitors obtained at embryonic day 11 (E11, E12 and E13 were analyzed. Results Neuronal progenitors were purified from telencephalic dissociates by a positive-selection strategy featuring surface labeling with tetanus-toxin and cholera-toxin followed by fluorescence-activated cell sorting. Microarray analyses revealed the fractions of miRNAs and mRNAs that were up-regulated or down-regulated in these neuronal progenitors at the beginning of cortical development. Nearly half of the dynamically expressed miRNAs were negatively correlated with the expression of their predicted target mRNAs. Conclusion These data support a regulatory role for miRNAs during the transition from neuronal progenitors into the earliest differentiating cortical neurons. In addition, by supplying a robust data set in which miRNA and mRNA profiles originate from the same purified cell type, this empirical study may facilitate the development of new algorithms to integrate various "-omics" data sets.

  16. A Progenitor Cell Expressing Transcription Factor RORγt Generates All Human Innate Lymphoid Cell Subsets.

    Science.gov (United States)

    Scoville, Steven D; Mundy-Bosse, Bethany L; Zhang, Michael H; Chen, Li; Zhang, Xiaoli; Keller, Karen A; Hughes, Tiffany; Chen, Luxi; Cheng, Stephanie; Bergin, Stephen M; Mao, Hsiaoyin C; McClory, Susan; Yu, Jianhua; Carson, William E; Caligiuri, Michael A; Freud, Aharon G

    2016-05-17

    The current model of murine innate lymphoid cell (ILC) development holds that mouse ILCs are derived downstream of the common lymphoid progenitor through lineage-restricted progenitors. However, corresponding lineage-restricted progenitors in humans have yet to be discovered. Here we identified a progenitor population in human secondary lymphoid tissues (SLTs) that expressed the transcription factor RORγt and was unique in its ability to generate all known ILC subsets, including natural killer (NK) cells, but not other leukocyte populations. In contrast to murine fate-mapping data, which indicate that only ILC3s express Rorγt, these human progenitor cells as well as human peripheral blood NK cells and all mature ILC populations expressed RORγt. Thus, all human ILCs can be generated through an RORγt(+) developmental pathway from a common progenitor in SLTs. These findings help establish the developmental signals and pathways involved in human ILC development.

  17. Seizure induces activation of multiple subtypes of neural progenitors and growth factors in hippocampus with neuronal maturation confined to dentate gyrus

    Energy Technology Data Exchange (ETDEWEB)

    Indulekha, Chandrasekharan L.; Sanalkumar, Rajendran [Neuro Stem Cell Biology Laboratory, Department of Neurobiology, Rajiv Gandhi Center for Biotechnology, Thiruvananthapuram, Kerala 695 014 (India); Thekkuveettil, Anoopkumar [Molecular Medicine, Biomedical Technology Wing, Sree Chitra Thirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, Kerala (India); James, Jackson, E-mail: jjames@rgcb.res.in [Neuro Stem Cell Biology Laboratory, Department of Neurobiology, Rajiv Gandhi Center for Biotechnology, Thiruvananthapuram, Kerala 695 014 (India)

    2010-03-19

    Adult hippocampal neurogenesis is altered in response to different physiological and pathological stimuli. GFAP{sup +ve}/nestin{sup +ve} radial glial like Type-1 progenitors are considered to be the resident stem cell population in adult hippocampus. During neurogenesis these Type-1 progenitors matures to GFAP{sup -ve}/nestin{sup +ve} Type-2 progenitors and then to Type-3 neuroblasts and finally differentiates into granule cell neurons. In our study, using pilocarpine-induced seizure model, we showed that seizure initiated activation of multiple progenitors in the entire hippocampal area such as DG, CA1 and CA3. Seizure induction resulted in activation of two subtypes of Type-1 progenitors, Type-1a (GFAP{sup +ve}/nestin{sup +ve}/BrdU{sup +ve}) and Type-1b (GFAP{sup +ve}/nestin{sup +ve}/BrdU{sup -ve}). We showed that majority of Type-1b progenitors were undergoing only a transition from a state of dormancy to activated form immediately after seizures rather than proliferating, whereas Type-1a showed maximum proliferation by 3 days post-seizure induction. Type-2 (GFAP{sup -ve}/nestin{sup +ve}/BrdU{sup +ve}) progenitors were few compared to Type-1. Type-3 (DCX{sup +ve}) progenitors showed increased expression of immature neurons only in DG region by 3 days after seizure induction indicating maturation of progenitors happens only in microenvironment of DG even though progenitors are activated in CA1 and CA3 regions of hippocampus. Also parallel increase in growth factors expression after seizure induction suggests that microenvironmental niche has a profound effect on stimulation of adult neural progenitors.

  18. Antibodies against Pax6 immunostain amacrine and ganglion cells and neuronal progenitors, but not rod precursors, in the normal and regenerating retina of the goldfish.

    Science.gov (United States)

    Hitchcock, P F; Macdonald, R E; VanDeRyt, J T; Wilson, S W

    1996-03-01

    Pax6 is a developmental regulatory gene that plays a key role in the development of the embryonic brain, eye, and retina. This gene is also expressed in discrete groups of neurons within the adult brain. In this study, antibodies raised against a fusion protein from a zebra fish pax6 cDNA were used to investigate the expression of the pax6 gene in the mature, growing, and regenerating retina of the goldfish. On western blots of retinal proteins, the pax6 antibodies recognize a single band at the approximate size of the zebra fish pax6 protein. In retinal sections, the antibodies label the nuclei of mature amacrine and some ganglion cells. At the retinal margin, where neurogenesis and cellular differentiation continually occur in goldfish, the antibodies label neuronal progenitors and the newly postmitotic neurons. Following injury and during neuronal regeneration, the antibodies label mitotically active progenitors of regenerating neurons. Rod precursors, proliferating cells that normally give rise solely to rod photoreceptors and are the presumed antecedents of the injury-stimulated neuronal progenitors, are not immunostained by antibodies to the pax6 protein. The results of this study document the identity of pax6-expressing cells in the mature retina and demonstrate that in the goldfish pax6 is expressed in neuronal progenitors during both retinal growth and regeneration.

  19. Minocycline inhibited the pro-apoptotic effect of microglia on neural progenitor cells and protected their neuronal differentiation in vitro.

    Science.gov (United States)

    Liu, Xuqing; Su, Huanxing; Chu, Tak-Ho; Guo, Anchen; Wu, Wutian

    2013-05-10

    Neural progenitor cell (NPC) transplantation offers great potential to treat spinal cord injury (SCI), but their efficiency is limited by poor survival and neuronal differentiation after transplantation. In the injury site, microglia may become activated and participate in the inflammation reaction. In vitro studies indicated that activated microglia might impair NPC survival and neuronal differentiation, but resting microglia did not. This study investigated the potential of minocycline to modify the negative effects of activated microglia on NPCs in vitro. First, the direct effects of minocycline on NPCs were tested. The results showed that at the concentration of 10μg/ml or lower, minocycline did not affect NPC survival and proliferation, but impaired neuronal differentiation. Then microglia were activated with lipopolysaccharide (LPS) or treated with LPS plus minocycline (LPSMC), and the effects of conditioned media on NPC apoptosis and differentiation were studied. The results showed that, compared with LPS treatment group, the microglia conditioned media of LPSMC treatment group resulted in a significantly lower apoptotic rate of NPCs, and increased the neuronal differentiation of NPCs. This suggested that minocycline might inhibit the negative effects of microglia on NPCs, and have the potential to support the survival and neuronal differentiation of transplanted NPCs for SCI.

  20. Specification of spatial identities of cerebellar neuron progenitors by ptf1a and atoh1 for proper production of GABAergic and glutamatergic neurons.

    Science.gov (United States)

    Yamada, Mayumi; Seto, Yusuke; Taya, Shinichiro; Owa, Tomoo; Inoue, Yukiko U; Inoue, Takayoshi; Kawaguchi, Yoshiya; Nabeshima, Yo-Ichi; Hoshino, Mikio

    2014-04-01

    In the cerebellum, the bHLH transcription factors Ptf1a and Atoh1 are expressed in distinct neuroepithelial regions, the ventricular zone (VZ) and the rhombic lip (RL), and are required for producing GABAergic and glutamatergic neurons, respectively. However, it is unclear whether Ptf1a or Atoh1 is sufficient for specifying GABAergic or glutamatergic neuronal fates. To test this, we generated two novel knock-in mouse lines, Ptf1a(Atoh1) and Atoh1(Ptf1a), that are designed to express Atoh1 and Ptf1a ectopically in the VZ and RL, respectively. In Ptf1a(Atoh1) embryos, ectopically Atoh1-expressing VZ cells produced glutamatergic neurons, including granule cells and deep cerebellar nuclei neurons. Correspondingly, in Atoh1(Ptf1a) animals, ectopically Ptf1a-expressing RL cells produced GABAergic populations, such as Purkinje cells and GABAergic interneurons. Consistent results were also obtained from in utero electroporation of Ptf1a or Atoh1 into embryonic cerebella, suggesting that Ptf1a and Atoh1 are essential and sufficient for GABAergic versus glutamatergic specification in the neuroepithelium. Furthermore, birthdating analyses with BrdU in the knock-in mice or with electroporation studies showed that ectopically produced fate-changed neuronal types were generated at temporal schedules closely simulating those of the wild-type RL and VZ, suggesting that the VZ and RL share common temporal information. Observations of knock-in brains as well as electroporated brains revealed that Ptf1a and Atoh1 mutually negatively regulate their expression, probably contributing to formation of non-overlapping neuroepithelial domains. These findings suggest that Ptf1a and Atoh1 specify spatial identities of cerebellar neuron progenitors in the neuroepithelium, leading to appropriate production of GABAergic and glutamatergic neurons, respectively.

  1. Progenitor cells from the CA3 region of the embryonic day 19 rat hippocampus generate region-specific neuronal phenotypes in vitro.

    Science.gov (United States)

    Shetty, Ashok K

    2004-01-01

    Progenitor cells that endure in different regions of the CNS after the initial neurogenesis can be expanded in culture and used as a source of donor tissue for grafting in neurodegenerative diseases. However, the proliferation and differentiation characteristics of residual neural progenitor cells from distinct regions of the CNS are mostly unknown. This study elucidated the characteristics of progenitor cells that endure in the CA3 region of the hippocampus after neurogenesis, by in vitro analyses of cells that are responsive to epidermal growth factor (EGF) or fibroblast growth factor-2 (FGF-2) in the embryonic day 19 (E19) rat hippocampus. Isolated cells from the E19 CA3 region formed neurospheres in the presence of either EGF or FGF-2, but the yield of neurospheres was greater with FGF-2 exposure, Differentiation cultures revealed a greater yield of neurons from FGF-2 neurospheres (60%) than from EGF neurospheres (35%). Exposure to brain-derived neurotrophic factor (BDNF) enhanced the yield of neurons from EGF neurospheres but had no consequence on FGF-2 neurospheres. A large number of neurons from EGF/FGF-2 neurospheres demonstrated clearly palpable morphological features of CA3 pyramidal neurons and lacked gamma-aminobutyric acid (GABA) expression. However, a fraction of neurons (17-20%) from EGF/FGF-2 neurospheres expressed GABA, and exposure to BDNF increased the number of GABAergic neurons (30%) from EGF neurospheres. Neurons from EGF/FGF-2 neurospheres also contained smaller populations of calbindin- and calretinin-positive interneuron-like cells. Thus, progenitor cells responsive to FGF-2 are prevalent in the CA3 region of the E19 rat hippocampus and give rise to a greater number of neurons than progenitor cells responsive to EGF. However, both FGF-2- and EGF-responsive progenitor cells from E19 CA3 region are capable of giving rise to CA3 field-specific phenotypic neurons. These results imply that progenitor cells that persist in the hippocampus after

  2. Functional Rescue of Dopaminergic Neuron Loss in Parkinson's Disease Mice After Transplantation of Hematopoietic Stem and Progenitor Cells.

    Science.gov (United States)

    Altarche-Xifro, Wassim; di Vicino, Umberto; Muñoz-Martin, Maria Isabel; Bortolozzi, Analía; Bové, Jordi; Vila, Miquel; Cosma, Maria Pia

    2016-06-01

    Parkinson's disease is a common neurodegenerative disorder, which is due to the loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and for which no definitive cure is currently available. Cellular functions in mouse and human tissues can be restored after fusion of bone marrow (BM)-derived cells with a variety of somatic cells. Here, after transplantation of hematopoietic stem and progenitor cells (HSPCs) in the SNpc of two different mouse models of Parkinson's disease, we significantly ameliorated the dopaminergic neuron loss and function. We show fusion of transplanted HSPCs with neurons and with glial cells in the ventral midbrain of Parkinson's disease mice. Interestingly, the hybrids can undergo reprogramming in vivo and survived up to 4weeks after transplantation, while acquiring features of mature astroglia. These newly generated astroglia produced Wnt1 and were essential for functional rescue of the dopaminergic neurons. Our data suggest that glial-derived hybrids produced upon fusion of transplanted HSPCs in the SNpc can rescue the Parkinson's disease phenotype via a niche-mediated effect, and can be exploited as an efficient cell-therapy approach. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  3. The Origin, Development and Molecular Diversity of Rodent Olfactory Bulb Glutamatergic Neurons Distinguished by Expression of Transcription Factor NeuroD1.

    Directory of Open Access Journals (Sweden)

    Laurent Roybon

    Full Text Available Production of olfactory bulb neurons occurs continuously in the rodent brain. Little is known, however, about cellular diversity in the glutamatergic neuron subpopulation. In the central nervous system, the basic helix-loop-helix transcription factor NeuroD1 (ND1 is commonly associated with glutamatergic neuron development. In this study, we utilized ND1 to identify the different subpopulations of olfactory bulb glutamategic neurons and their progenitors, both in the embryo and postnatally. Using knock-in mice, transgenic mice and retroviral transgene delivery, we demonstrate the existence of several different populations of glutamatergic olfactory bulb neurons, the progenitors of which are ND1+ and ND1- lineage-restricted, and are temporally and regionally separated. We show that the first olfactory bulb glutamatergic neurons produced - the mitral cells - can be divided into molecularly diverse subpopulations. Our findings illustrate the complexity of neuronal diversity in the olfactory bulb and that seemingly homogenous neuronal populations can consist of multiple subpopulations with unique molecular signatures of transcription factors and expressing neuronal subtype-specific markers.

  4. Directed differentiation of porcine epiblast-derived neural progenitor cells into neurons and glia

    DEFF Research Database (Denmark)

    Rasmussen, Mikkel Aabech; Hall, Vanessa Jane; Carter, T.F.

    2011-01-01

    Neural progenitor cells (NPCs) are promising candidates for cell-based therapy of neurodegenerative diseases; however, safety concerns must be addressed through transplantation studies in large animal models, such as the pig. The aim of this study was to derive NPCs from porcine blastocysts and e...

  5. Lgr5(+ve) stem/progenitor cells contribute to nephron formation during kidney development

    NARCIS (Netherlands)

    Barker, N.; Rookmaaker, M.B.; Kujala, P.; Ng, A.; Leushacke, M.; Snippert, H.; van de Wetering, M.; Tan, S.; van Es, J.H.; Huch, M.; Poulsom, R.; Verhaar, M.C.; Peters, P.J.; Clevers, H.

    2012-01-01

    Multipotent stem cells and their lineage-restricted progeny drive nephron formation within the developing kidney. Here, we document expression of the adult stem cell marker Lgr5 in the developing kidney and assess the stem/progenitor identity of Lgr5(+ve) cells via in vivo lineage tracing. The appea

  6. Lgr5(+ve) Stem/Progenitor Cells Contribute to Nephron Formation during Kidney Development

    NARCIS (Netherlands)

    Barker, Nick; Rookmaaker, Maarten B.; Kujala, Pekka; Ng, Annie; Leushacke, Marc; Snippert, Hugo; van de Wetering, Marc; Tan, Shawna; Van Es, Johan H.; Huch, Meritxell; Poulsom, Richard; Verhaar, Marianne C.; Peters, Peter J.; Clevers, Hans

    2012-01-01

    Multipotent stem cells and their lineage-restricted progeny drive nephron formation within the developing kidney. Here, we document expression of the adult stem cell marker Lgr5 in the developing kidney and assess the stem/progenitor identity of Lgr5(+ve) cells via in vivo lineage tracing. The appea

  7. Neuregulin 1 Type II-ErbB Signaling Promotes Cell Divisions Generating Neurons from Neural Progenitor Cells in the Developing Zebrafish Brain.

    Science.gov (United States)

    Sato, Tomomi; Sato, Fuminori; Kamezaki, Aosa; Sakaguchi, Kazuya; Tanigome, Ryoma; Kawakami, Koichi; Sehara-Fujisawa, Atsuko

    2015-01-01

    Post-mitotic neurons are generated from neural progenitor cells (NPCs) at the expense of their proliferation. Molecular and cellular mechanisms that regulate neuron production temporally and spatially should impact on the size and shape of the brain. While transcription factors such as neurogenin1 (neurog1) and neurod govern progression of neurogenesis as cell-intrinsic mechanisms, recent studies show regulatory roles of several cell-extrinsic or intercellular signaling molecules including Notch, FGF and Wnt in production of neurons/neural progenitor cells from neural stem cells/radial glial cells (NSCs/RGCs) in the ventricular zone (VZ). However, it remains elusive how production of post-mitotic neurons from neural progenitor cells is regulated in the sub-ventricular zone (SVZ). Here we show that newborn neurons accumulate in the basal-to-apical direction in the optic tectum (OT) of zebrafish embryos. While neural progenitor cells are amplified by mitoses in the apical ventricular zone, neurons are exclusively produced through mitoses of neural progenitor cells in the sub-basal zone, later in the sub-ventricular zone, and accumulate apically onto older neurons. This neurogenesis depends on Neuregulin 1 type II (NRG1-II)-ErbB signaling. Treatment with an ErbB inhibitor, AG1478 impairs mitoses in the sub-ventricular zone of the optic tectum. Removal of AG1478 resumes sub-ventricular mitoses without precedent mitoses in the apical ventricular zone prior to basal-to-apical accumulation of neurons, suggesting critical roles of ErbB signaling in mitoses for post-mitotic neuron production. Knockdown of NRG1-II impairs both mitoses in the sub-basal/sub-ventricular zone and the ventricular zone. Injection of soluble human NRG1 into the developing brain ameliorates neurogenesis of NRG1-II-knockdown embryos, suggesting a conserved role of NRG1 as a cell-extrinsic signal. From these results, we propose that NRG1-ErbB signaling stimulates cell divisions generating neurons from

  8. Elevated IKKα accelerates the differentiation of human neuronal progenitor cells and induces MeCP2-dependent BDNF expression.

    Directory of Open Access Journals (Sweden)

    Ali Khoshnan

    Full Text Available The IκB kinase α (IKKα is implicated in the differentiation of epithelial and immune cells. We examined whether IKKα also plays a role in the differentiation and maturation of embryonic human neuronal progenitor cells (NPCs. We find that expression of an extra copy of IKKα (IKKα+ blocks self-renewal and accelerates the differentiation of NPCs. This coincides with reduced expression of the Repressor Element Silencing Transcription Factor/Neuron-Restrictive Silencing Factor (REST/NRSF, which is a prominent inhibitor of neurogenesis, and subsequent induction of the pro-differentiation non-coding RNA, miR-124a. However, the effects of IKKα on REST/NRSF and miR-124a expression are likely to be indirect. IKKα+ neurons display extensive neurite outgrowth and accumulate protein markers of neuronal maturation such as SCG10/stathmin-2, postsynaptic density 95 (PSD95, syntaxin, and methyl-CpG binding protein 2 (MeCP2. Interestingly, IKKα associates with MeCP2 in the nuclei of human neurons and can phosphorylate MeCP2 in vitro. Using chromatin immunoprecipitation assays, we find that IKKα is recruited to the exon-IV brain-derived neurotrophic factor (BDNF promoter, which is a well-characterized target of MeCP2 activity. Moreover, IKKα induces the transcription of BDNF and knockdown expression of MeCP2 interferes with this event. These studies highlight a role for IKKα in accelerating the differentiation of human NPCs and identify IKKα as a potential regulator of MeCP2 function and BDNF expression.

  9. The addicted brain craves new neurons: putative role for adult-born progenitors in promoting recovery.

    Science.gov (United States)

    Mandyam, Chitra D; Koob, George F

    2012-04-01

    Addiction is a chronic relapsing disorder associated with compulsive drug taking, drug seeking and a loss of control in limiting intake, reflected in three stages of a recurrent cycle: binge/intoxication, withdrawal/negative affect, and preoccupation/anticipation ("craving"). This review discusses the role of adult-born neural and glial progenitors in drug seeking associated with the different stages of the addiction cycle. A review of the current literature suggests that the loss of newly born progenitors, particularly in hippocampal and cortical regions, plays a role in determining vulnerability to relapse in rodent models of drug addiction. The normalization of drug-impaired neurogenesis or gliogenesis may help reverse neuroplasticity during abstinence and, thus, may help reduce the vulnerability to relapse and aid recovery. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Microglia-induced IL-6 protects against neuronal loss following HSV-1 infection of neural progenitor cells.

    Science.gov (United States)

    Chucair-Elliott, Ana J; Conrady, Christopher; Zheng, Min; Kroll, Chandra M; Lane, Thomas E; Carr, Daniel J J

    2014-09-01

    Herpes virus type 1 (HSV-1) is one of the most widespread human pathogens and accounts for more than 90% of cases of herpes simplex encephalitis (HSE) causing severe and permanent neurologic sequelae among surviving patients. We hypothesize such CNS deficits are due to HSV-1 infection of neural progenitor cells (NPCs). In vivo, HSV-1 infection was found to diminish NPC numbers in the subventricular zone. Upon culture of NPCs in conditions that stimulate their differentiation, we found HSV-1 infection of NPCs resulted in the loss of neuronal precursors with no significant change in the percentage of astrocytes or oligodendrocytes. We propose this is due a direct effect of HSV-1 on neuronal survival without alteration of the differentiation process. The neuronal loss was prevented by the addition of microglia or conditioned media from NPC/microglia co-cultures. Using neutralizing antibodies and recombinant cytokines, we identified interleukin-6 (IL-6) as responsible for the protective effect by microglia, likely through its downstream Signal Transducer and Activator of Transcription 3 (STAT3) cascade.

  11. The Addicted Brain Craves New Neurons: Putative Role for Adult-Born Progenitors in Promoting Recovery

    OpenAIRE

    Mandyam, Chitra D.; Koob, George F.

    2012-01-01

    Addiction is a chronic relapsing disorder associated with compulsive drug taking and drug seeking and a loss of control in limiting intake, reflected in three stages of a recurrent cycle: binge/intoxication, withdrawal/negative affect, and preoccupation/anticipation (“craving”). This review discusses the role of adult-born neural and glial progenitors in drug-seeking associated with the different stages of the addiction cycle. A review of the current literature suggests that the loss of newly...

  12. Failed cytokinesis of neural progenitors in citron kinase-deficient rats leads to multiciliated neurons.

    Science.gov (United States)

    Anastas, Sara B; Mueller, Dorit; Semple-Rowland, Susan L; Breunig, Joshua J; Sarkisian, Matthew R

    2011-02-01

    Most, if not all, cortical neurons possess a single primary cilium; however, little is known about the mechanisms that control neuronal ciliogenesis. The Citron kinase-deficient (Citron-K(fh/fh)) rat, a model in which failed cytokinesis during development produces cortical neurons containing multiple cellular organelles, provides a unique system in which to examine the relationship between centriole inheritance and neuronal ciliogenesis. In this study, we analyzed the cerebral cortex of these animals using immunohistochemistry, serial confocal, and electron microscopy to determine if the multinucleated neurons present in the cortex of these animals also possess multiple centrioles and cilia. We found that neurons containing multiple nuclei possessed multiple centrioles and cilia whose lengths varied across cortical regions. Despite the presence of multiple cilia, we found that perinatal expression of adenylyl cyclase III, a cilia-specific marker, and somatostatin receptor 3, a receptor enriched in cilia, were preserved in developing Citron-K(fh/fh) brain. Together, these results show that multinucleated neurons arising from defective cytokinesis can extend multiple cilia.

  13. Neural progenitor cells attenuate inflammatory reactivity and neuronal loss in an animal model of inflamed AD brain

    Directory of Open Access Journals (Sweden)

    Wang Yu

    2009-12-01

    Full Text Available Abstract Background Transplantation of neural progenitor cells (NPC constitutes a putative therapeutic maneuver for use in treatment of neurodegenerative diseases. At present, effects of NPC transplantation in Alzheimer's disease (AD brain are largely unknown and a primary objective of this work was to demonstrate possible efficacy of NPC administration in an animal model of AD. The benefits of transplantation could involve a spectrum of effects including replacement of endogenous neurons or by conferring neuroprotection with enhancement of neurotrophic factors or diminishing levels of neurotoxic agents. Since chronic inflammation is a characteristic property of AD brain, we considered that transplantation of NPC could have particular utility in inhibiting ongoing inflammatory reactivity. We have tested intrahippocampal transplantation of NPC for efficacy in attenuating inflammatory responses and for neuroprotection in beta-amyloid (Aβ1-42 peptide-injected rat hippocampus. Methods Spheres of neural progenitor cells were grown from dissociated telencephalon tissue of rat embryos. NPC were infected with lentiviral vector green fluorescent protein (GFP with subsequent cell transplantation into rat hippocampus previously injected (3 d prior with Aβ1-42 peptide or PBS control. Immunohistochemical analysis was carried out (7 d post-NPC transplantation, 10 d post-peptide/PBS injection for GFP, microgliosis (Iba-1 marker, astrogliosis (GFAP marker, neuron viability (MAP-2 marker and levels of the proinflammatory cytokine, TNF-α. Results Successful infection of cultured NPC with lentiviral vector green fluorescent protein (GFP was demonstrated prior to cell transplantation into rat hippocampus. In vivo, immunohistochemical staining showed migration of GFP-positive cells, in a region of dentate gyrus between Aβ1-42/PBS injection site and NPC transplantation site, was increased ×2.8-fold with Aβ1-42 compared to PBS injection. Double immunostaining in

  14. Long-term potentiation promotes proliferation/survival and neuronal differentiation of neural stem/progenitor cells.

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    Taesup Cho

    Full Text Available Neural stem cell (NSC replacement therapy is considered a promising cell replacement therapy for various neurodegenerative diseases. However, the low rate of NSC survival and neurogenesis currently limits its clinical potential. Here, we examined if hippocampal long-term potentiation (LTP, one of the most well characterized forms of synaptic plasticity, promotes neurogenesis by facilitating proliferation/survival and neuronal differentiation of NSCs. We found that the induction of hippocampal LTP significantly facilitates proliferation/survival and neuronal differentiation of both endogenous neural progenitor cells (NPCs and exogenously transplanted NSCs in the hippocampus in rats. These effects were eliminated by preventing LTP induction by pharmacological blockade of the N-methyl-D-aspartate glutamate receptor (NMDAR via systemic application of the receptor antagonist, 3-[(R-2-carboxypiperazin-4-yl]-propyl-1-phosphonic acid (CPP. Moreover, using a NPC-neuron co-culture system, we were able to demonstrate that the LTP-promoted NPC neurogenesis is at least in part mediated by a LTP-increased neuronal release of brain-derived neurotrophic factor (BDNF and its consequent activation of tropomysosin receptor kinase B (TrkB receptors on NSCs. Our results indicate that LTP promotes the neurogenesis of both endogenous and exogenously transplanted NSCs in the brain. The study suggests that pre-conditioning of the host brain receiving area with a LTP-inducing deep brain stimulation protocol prior to NSC transplantation may increase the likelihood of success of using NSC transplantation as an effective cell therapy for various neurodegenerative diseases.

  15. Talpid3-binding centrosomal protein Cep120 is required for centriole duplication and proliferation of cerebellar granule neuron progenitors.

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    Chuanqing Wu

    Full Text Available Granule neuron progenitors (GNPs are the most abundant neuronal type in the cerebellum. GNP proliferation and thus cerebellar development require Sonic hedgehog (Shh secreted from Purkinje cells. Shh signaling occurs in primary cilia originating from the mother centriole. Centrioles replicate only once during a typical cell cycle and are responsible for mitotic spindle assembly and organization. Recent studies have linked cilia function to cerebellar morphogenesis, but the role of centriole duplication in cerebellar development is not known. Here we show that centrosomal protein Cep120 is asymmetrically localized to the daughter centriole through its interaction with Talpid3 (Ta3, another centrosomal protein. Cep120 null mutant mice die in early gestation with abnormal heart looping. Inactivation of Cep120 in the central nervous system leads to both hydrocephalus, due to the loss of cilia on ependymal cells, and severe cerebellar hypoplasia, due to the failed proliferation of GNPs. The mutant GNPs lack Hedgehog pathway activity. Cell biological studies show that the loss of Cep120 results in failed centriole duplication and consequently ciliogenesis, which together underlie Cep120 mutant cerebellar hypoplasia. Thus, our study for the first time links a centrosomal protein necessary for centriole duplication to cerebellar morphogenesis.

  16. Cell-Cell Connection Enhances Proliferation and Neuronal Differentiation of Rat Embryonic Neural Stem/Progenitor Cells

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    Qian Jiao

    2017-07-01

    Full Text Available Cell-cell interaction as one of the niche signals plays an important role in the balance of stem cell quiescence and proliferation or differentiation. In order to address the effect and the possible mechanisms of cell-cell connection on neural stem/progenitor cells (NSCs/NPCs proliferation and differentiation, upon passaging, NSCs/NPCs were either dissociated into single cell as usual (named Group I or mechanically triturated into a mixture of single cell and small cell clusters containing direct cell-cell connections (named Group II. Then the biological behaviors including proliferation and differentiation of NSCs/NPCs were observed. Moreover, the expression of gap junction channel, neurotrophic factors and the phosphorylation status of MAPK signals were compared to investigate the possible mechanisms. Our results showed that, in comparison to the counterparts in Group I, NSCs/NPCs in Group II survived well with preferable neuronal differentiation. In coincidence with this, the expression of connexin 45 (Cx45, as well as brain derived neurotrophic factor (BDNF and neurotrophin 3 (NT-3 in Group II were significantly higher than those in Group I. Phosphorylation of ERK1/2 and JNK2 were significantly upregulated in Group II too, while no change was found about p38. Furthermore, the differences of NSCs/NPCs biological behaviors between Group I and II completely disappeared when ERK and JNK phosphorylation were inhibited. These results indicated that cell-cell connection in Group II enhanced NSCs/NPCs survival, proliferation and neuronal differentiation through upregulating the expression of gap junction and neurotrophic factors. MAPK signals- ERK and JNK might contribute to the enhancement. Efforts for maintaining the direct cell-cell connection are worth making to provide more favorable niches for NSCs/NPCs survival, proliferation and neuronal differentiation.

  17. Delta-like 1 participates in the specification of ventral midbrain progenitor derived dopaminergic neurons

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    Bauer, Matthias; Szulc, Jolanta; Meyer, Morten

    2008-01-01

    Delta-like 1 (Dlk1), a member of the Delta/Notch protein family, is expressed in the mouse ventral midbrain (VM) as early as embryonic day 11.5 (E11.5) followed by exclusive expression in tyrosine 3-monooxygenase (TH) positive neurons from E12.5 onwards. To further elucidate the yet unknown funct...

  18. RBP-J is not required for granule neuron progenitor development and medulloblastoma initiated by Hedgehog pathway activation in the external germinal layer

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    Hallahan Andrew R

    2010-10-01

    Full Text Available Abstract Background The Notch signalling pathway plays crucial roles in neural development, functioning by preventing premature differentiation and promotion of glial cell fates. In the developing cerebellum Notch pathway components are expressed in granule neuron progenitors of the external germinal layer (EGL but the precise function of Notch in these cells is unclear. The Hedgehog pathway is also crucial in cerebellar development, mainly via control of the cell cycle, and persistent activation of the pathways leads to the cerebellar tumour medulloblastoma. Interactions between Hedgehog and Notch have been reported in normal brain development as well as in Hedgehog pathway induced medulloblastoma but the molecular details of this interaction are not known and we investigate here the role of Notch signalling in the development of the EGL and the intersection between the two pathways in cerebellar granule neuron progenitors and in medulloblastoma. Results RBP-J is the major downstream effector of all four mammalian Notch receptors and the RBP-J conditional mouse facilitates inactivation of canonical Notch signals. Patched1 is a negative regulator of Hedgehog signalling and the Patched1 conditional mouse is widely used to activate Hedgehog signalling via Patched1 deletion in specific cell types. The conditional mouse lines were crossed with a Math1-Cre line to delete the two genes in granule neuron progenitors from embryonic day 10.5. While deletion of only Patched1 as well as Patched1 together with RBP-J leads to formation of medulloblastoma concomitant with disorganisation of cell layers, loss of RBP-J from granule neuron progenitors has no obvious effect on overall cerebellar morphology or differentiation and maturation of the different cerebellar cell types. Conclusions Our results suggest that even though Notch signalling has been shown to play important roles in cerebellar development, signalling via RBP-J is surprisingly not required in

  19. The Role of Neonatal Carnitine Palmitoyl Transferase Deficiency Type II on Proliferation of Neuronal Progenitor Cells and Layering of the Cerebral Cortex in the Developing Brain

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    Heepeel Chang

    2007-06-01

    Full Text Available Neonatal Carnitine Palmitoyl Transferase Deficiency Type II, characterized by the absence of CPT II enzyme, is one of the lethal disorders of mitochondrial fatty acid oxidation. CPT II regulates the conversion of long chain fatty acids, so that its product, acyl-CoA esters, can enter the Krebs cycle and generate energy. Neonatal mutations of CPT II lead to severe disruption of the metabolism of long-chain fatty acids and result in dysmorphic features, cystic renal dysplasia, and neuronal migration defects. Examination of the brain from an approximately 15-week gestation human fetus with CPT II deficiency revealed premature formation of cerebral cortical gyri and sulci and significantly lower levels of neuronal cell proliferation in the ventricular and subventricular zones as compared to the reference cases. We used immunohistochemical markers to further characterize the effect of CPT II deficiency on progenitor cell proliferation and layering of neurons. These studies demonstrated a premature generation of layer 5 cortical neurons. In addition, both the total number and percentage of progenitor cells proliferating in the ventricular zone were markedly reduced in the CPT II case in comparison to a reference case. Our results indicate that CPT II deficiency alters the normal program of cellular proliferation and differentiation in the cortex, with early differentiation of progenitor cells associated with premature cortical maturation.

  20. Organic cation transporter-mediated ergothioneine uptake in mouse neural progenitor cells suppresses proliferation and promotes differentiation into neurons.

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    Takahiro Ishimoto

    Full Text Available The aim of the present study is to clarify the functional expression and physiological role in neural progenitor cells (NPCs of carnitine/organic cation transporter OCTN1/SLC22A4, which accepts the naturally occurring food-derived antioxidant ergothioneine (ERGO as a substrate in vivo. Real-time PCR analysis revealed that mRNA expression of OCTN1 was much higher than that of other organic cation transporters in mouse cultured cortical NPCs. Immunocytochemical analysis showed colocalization of OCTN1 with the NPC marker nestin in cultured NPCs and mouse embryonic carcinoma P19 cells differentiated into neural progenitor-like cells (P19-NPCs. These cells exhibited time-dependent [(3H]ERGO uptake. These results demonstrate that OCTN1 is functionally expressed in murine NPCs. Cultured NPCs and P19-NPCs formed neurospheres from clusters of proliferating cells in a culture time-dependent manner. Exposure of cultured NPCs to ERGO or other antioxidants (edaravone and ascorbic acid led to a significant decrease in the area of neurospheres with concomitant elimination of intracellular reactive oxygen species. Transfection of P19-NPCs with small interfering RNA for OCTN1 markedly promoted formation of neurospheres with a concomitant decrease of [(3H]ERGO uptake. On the other hand, exposure of cultured NPCs to ERGO markedly increased the number of cells immunoreactive for the neuronal marker βIII-tubulin, but decreased the number immunoreactive for the astroglial marker glial fibrillary acidic protein (GFAP, with concomitant up-regulation of neuronal differentiation activator gene Math1. Interestingly, edaravone and ascorbic acid did not affect such differentiation of NPCs, in contrast to the case of proliferation. Knockdown of OCTN1 increased the number of cells immunoreactive for GFAP, but decreased the number immunoreactive for βIII-tubulin, with concomitant down-regulation of Math1 in P19-NPCs. Thus, OCTN1-mediated uptake of ERGO in NPCs inhibits

  1. Nuclear progesterone receptors are up-regulated by estrogens in neurons and radial glial progenitors in the brain of zebrafish.

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    Nicolas Diotel

    Full Text Available In rodents, there is increasing evidence that nuclear progesterone receptors are transiently expressed in many regions of the developing brain, notably outside the hypothalamus. This suggests that progesterone and/or its metabolites could be involved in functions not related to reproduction, particularly in neurodevelopment. In this context, the adult fish brain is of particular interest, as it exhibits constant growth and high neurogenic activity that is supported by radial glia progenitors. However, although synthesis of neuroprogestagens has been documented recently in the brain of zebrafish, information on the presence of progesterone receptors is very limited. In zebrafish, a single nuclear progesterone receptor (pgr has been cloned and characterized. Here, we demonstrate that this pgr is widely distributed in all regions of the zebrafish brain. Interestingly, we show that Pgr is strongly expressed in radial glial cells and more weakly in neurons. Finally, we present evidence, based on quantitative PCR and immunohistochemistry, that nuclear progesterone receptor mRNA and proteins are upregulated by estrogens in the brain of adult zebrafish. These data document for the first time the finding that radial glial cells are preferential targets for peripheral progestagens and/or neuroprogestagens. Given the crucial roles of radial glial cells in adult neurogenesis, the potential effects of progestagens on their activity and the fate of daughter cells require thorough investigation.

  2. Novel subcellular localization of the DNA helicase Twinkle at the kinetochore complex during mitosis in neuronal-like progenitor cells.

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    Uittenbogaard, Martine; Chiaramello, Anne

    2016-03-01

    During mitosis, the kinetochore, a multi-protein structure located on the centromeric DNA, is responsible for proper segregation of the replicated genome. More specifically, the outer kinetochore complex component Ndc80/Hec1 plays a critical role in regulating microtubule attachment to the spindle for accurate sister chromatid segregation. In addition, DNA helicases play a key contribution for precise and complete disjunction of sister chromatids held together through double-stranded DNA catenations until anaphase. In this study, we focused our attention on the nuclear-encoded DNA helicase Twinkle, which functions as an essential helicase for replication of mitochondrial DNA. It regulates the copy number of the mitochondrial genome, while maintaining its integrity, two processes essential for mitochondrial biogenesis and bioenergetic functions. Although the majority of the Twinkle protein is imported into mitochondria, a small fraction remains cytosolic with an unknown function. In this study, we report a novel expression pattern of Twinkle during chromosomal segregation at distinct mitotic phases. By immunofluorescence microscopy, we found that Twinkle protein colocalizes with the outer kinetochore protein HEC1 as early as prophase until late anaphase in neuronal-like progenitor cells. Thus, our collective results have revealed an unexpected cell cycle-regulated expression pattern of the DNA helicase Twinkle, known for its role in mtDNA replication. Therefore, its recruitment to the kinetochore suggests an evolutionary conserved function for both mitochondrial and nuclear genomic inheritance.

  3. GDNF secreting human neural progenitor cells protect dying motor neurons, but not their projection to muscle, in a rat model of familial ALS.

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    Masatoshi Suzuki

    Full Text Available BACKGROUND: Amyotrophic lateral sclerosis (ALS is a fatal, progressive neurodegenerative disease characterized by rapid loss of muscle control and eventual paralysis due to the death of large motor neurons in the brain and spinal cord. Growth factors such as glial cell line derived neurotrophic factor (GDNF are known to protect motor neurons from damage in a range of models. However, penetrance through the blood brain barrier and delivery to the spinal cord remains a serious challenge. Although there may be a primary dysfunction in the motor neuron itself, there is also increasing evidence that excitotoxicity due to glial dysfunction plays a crucial role in disease progression. Clearly it would be of great interest if wild type glial cells could ameliorate motor neuron loss in these models, perhaps in combination with the release of growth factors such as GDNF. METHODOLOGY/PRINCIPAL FINDINGS: Human neural progenitor cells can be expanded in culture for long periods and survive transplantation into the adult rodent central nervous system, in some cases making large numbers of GFAP positive astrocytes. They can also be genetically modified to release GDNF (hNPC(GDNF and thus act as long-term 'mini pumps' in specific regions of the rodent and primate brain. In the current study we genetically modified human neural stem cells to release GDNF and transplanted them into the spinal cord of rats over-expressing mutant SOD1 (SOD1(G93A. Following unilateral transplantation into the spinal cord of SOD1(G93A rats there was robust cellular migration into degenerating areas, efficient delivery of GDNF and remarkable preservation of motor neurons at early and end stages of the disease within chimeric regions. The progenitors retained immature markers, and those not secreting GDNF had no effect on motor neuron survival. Interestingly, this robust motor neuron survival was not accompanied by continued innervation of muscle end plates and thus resulted in no

  4. Impact of the Autism-Associated Long Noncoding RNA MSNP1AS on Neuronal Architecture and Gene Expression in Human Neural Progenitor Cells

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    Jessica J. DeWitt

    2016-09-01

    Full Text Available We previously identified the long noncoding RNA (lncRNA MSNP1AS (moesin pseudogene 1, antisense as a functional element revealed by genome wide significant association with autism spectrum disorder (ASD. MSNP1AS expression was increased in the postmortem cerebral cortex of individuals with ASD and particularly in individuals with the ASD-associated genetic markers on chromosome 5p14.1. Here, we mimicked the overexpression of MSNP1AS observed in postmortem ASD cerebral cortex in human neural progenitor cell lines to determine the impact on neurite complexity and gene expression. ReNcell CX and SK-N-SH were transfected with an overexpression vector containing full-length MSNP1AS. Neuronal complexity was determined by the number and length of neuronal processes. Gene expression was determined by strand-specific RNA sequencing. MSNP1AS overexpression decreased neurite number and neurite length in both human neural progenitor cell lines. RNA sequencing revealed changes in gene expression in proteins involved in two biological processes: protein synthesis and chromatin remodeling. These data indicate that overexpression of the ASD-associated lncRNA MSNP1AS alters the number and length of neuronal processes. The mechanisms by which MSNP1AS overexpression impacts neuronal differentiation may involve protein synthesis and chromatin structure. These same biological processes are also implicated by rare mutations associated with ASD, suggesting convergent mechanisms.

  5. Adult human brain neural progenitor cells (NPCs and fibroblast-like cells have similar properties in vitro but only NPCs differentiate into neurons.

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    Thomas In-Hyeup Park

    Full Text Available The ability to culture neural progenitor cells from the adult human brain has provided an exciting opportunity to develop and test potential therapies on adult human brain cells. To achieve a reliable and reproducible adult human neural progenitor cell (AhNPC culture system for this purpose, this study fully characterized the cellular composition of the AhNPC cultures, as well as the possible changes to this in vitro system over prolonged culture periods. We isolated cells from the neurogenic subventricular zone/hippocampus (SVZ/HP of the adult human brain and found a heterogeneous culture population comprised of several types of post-mitotic brain cells (neurons, astrocytes, and microglia, and more importantly, two distinct mitotic cell populations; the AhNPCs, and the fibroblast-like cells (FbCs. These two populations can easily be mistaken for a single population of AhNPCs, as they both proliferate under AhNPC culture conditions, form spheres and express neural progenitor cell and early neuronal markers, all of which are characteristics of AhNPCs in vitro. However, despite these similarities under proliferating conditions, under neuronal differentiation conditions, only the AhNPCs differentiated into functional neurons and glia. Furthermore, AhNPCs showed limited proliferative capacity that resulted in their depletion from culture by 5-6 passages, while the FbCs, which appear to be from a neurovascular origin, displayed a greater proliferative capacity and dominated the long-term cultures. This gradual change in cellular composition resulted in a progressive decline in neurogenic potential without the apparent loss of self-renewal in our cultures. These results demonstrate that while AhNPCs and FbCs behave similarly under proliferative conditions, they are two different cell populations. This information is vital for the interpretation and reproducibility of AhNPC experiments and suggests an ideal time frame for conducting Ah

  6. High neuronal/astroglial differentiation plasticity of adult rat hippocampal neural stem/progenitor cells in response to the effects of embryonic and adult cerebrospinal fluids.

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    Peirouvi, T; Yekani, F; Azarnia, M; Massumi, M

    2015-01-01

    Hippocampal neural stem/progenitor cells (hipp-NS/PCs) of the adult mammalian brain are important sources of neuronal and gial cell production. In this study, the main goal is to investigate the plasticity of these cells in neuronal/astroglial differentiations. To this end, the differentiation of the hipp-NS/PCs isolated from 3-month-old Wistar rats was investigated in response to the embryonic cerebrospinal fluid (E-CSF) including E13.5, E17-CSF and the adult cerebrospinal fluid (A-CSF), all extracted from rats. CSF samples were selected based on their effects on cell behavioral parameters. Primary cell culture was performed in the presence of either normal or high levels of KCL in a culture medium. High levels of KCL cause cell depolarization, and thus the activation of quiescent NSCs. Results from immunocytochemistry (ICC) and semi-quantitative RT-PCR (sRT-PCR) techniques showed that in E-CSF-treated groups, neuronal differentiation increased (E17>E13.5). In contrast, A-CSF decreased and increased neuronal and astroglial differentiations, respectively. Cell survivability and/or proliferation (S/P), evaluated by an MTT assay, increased by E13.5 CSF, but decreased by both E17 CSF and A-CSF. Based on the results, it is finally concluded that adult rat hippocampal proliferative cells are not restricted progenitors but rather show high plasticity in neuronal/astroglial differentiation according to the effects of CSF samples. In addition, using high concentrations of KCL in the primary cell culture led to an increase in the number of NSCs, which in turn resulted in the increase in neuronal or astroglial differentiations after CSF treatment.

  7. Claulansine F promoted the neuronal differentiation of neural stem and progenitor cells through Akt/GSK-3β/β-catenin pathway.

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    Huang, Ju-Yang; Ma, Yin-Zhong; Yuan, Yu-He; Zuo, Wei; Chu, Shi-Feng; Liu, Hang; Du, Guan-Hua; Zhang, Dong-Ming; Chen, Nai-Hong

    2016-09-05

    The persistence of neurogenesis raises the idea that neurons produced by the resident or transplanted neural stem cells could replace the neurons lost from brain injury or neurodegenerative disease. Therefore, compounds or methods for promoting neuronal differentiation become the focus of neurodegenerative disease therapy research. Claulansine F (Clau F), a newly discovered carbazole alkaloid, has been showed to induce neuritogenesis in PC12 cells. Herein, we studied the effect of Clau F on neuronal differentiation of neural stem/progenitor cells (NS/PCs). The current study demonstrated that Clau F initiated neuronal differentiation with a significant increase of TuJ1-positive cells and TuJ1 protein levels. We also found that Clau F promoted the maturity and sustainability of neurons by increasing MAP2-positive cells and MAP2 protein levels. At the same time, Clau F significantly inhibited the proliferation of NS/PCs. The underlying mechanism of Clau F was preliminary explored. Clau F treatment resulted in a profound increase of phosphorylation of Akt and GSK-3β, which led to GSK-3β inhibition and subsequently the nuclear accumulation of β-catenin. Further, the interaction between β-catenin and p300 in the nucleus was enhanced and the transcription of p300/β-catenin responsive genes were increased significantly (c-jun, fra-1) by Clau F. Importantly, the positive effect of Clau F on neuronal differentiation was abolished by Akti-1/2, a specific inhibitor of Akt-1/2 kinase, which indicated the involvement of Akt/GSK-3β in Clau F-mediated neuronal differentiation. In conclusion, these data suggested that Clau F promoted neuronal differentiation through Akt/GSK-3β/β-catenin signaling pathway in NS/PCs.

  8. Long-term omega-3 supplementation modulates behavior, hippocampal fatty acid concentration, neuronal progenitor proliferation and central TNF-α expression in 7 month old unchallenged mice.

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    Grundy, Trent; Toben, Catherine; Jaehne, Emily J; Corrigan, Frances; Baune, Bernhard T

    2014-01-01

    Dietary polyunsaturated fatty acid (PUFA) manipulation is being investigated as a potential therapeutic supplement to reduce the risk of developing age-related cognitive decline (ARCD). Animal studies suggest that high omega (Ω)-3 and low Ω-6 dietary content reduces cognitive decline by decreasing central nervous system (CNS) inflammation and modifying neuroimmune activity. However, no previous studies have investigated the long term effects of Ω-3 and Ω-6 dietary levels in healthy aging mice leaving the important question about the preventive effects of Ω-3 and Ω-6 on behavior and underlying molecular pathways unaddressed. We aimed to investigate the efficacy of long-term Ω-3 and Ω-6 PUFA dietary supplementation in mature adult C57BL/6 mice. We measured the effect of low, medium, and high Ω-3:Ω-6 dietary ratio, given from the age of 3-7 months, on anxiety and cognition-like behavior, hippocampal tissue expression of TNF-α, markers of neuronal progenitor proliferation and gliogenesis and serum cytokine concentration. Our results show that a higher Ω-3:Ω-6 PUFA diet ratio increased hippocampal PUFA, increased anxiety, improved hippocampal dependent spatial memory and reduced hippocampal TNF-α levels compared to a low Ω-3:Ω-6 diet. Furthermore, serum TNF-α concentration was reduced in the higher Ω-3:Ω-6 PUFA ratio supplementation group while expression of the neuronal progenitor proliferation markers KI67 and doublecortin (DCX) was increased in the dentate gyrus as opposed to the low Ω-3:Ω-6 group. Conversely, Ω-3:Ω-6 dietary PUFA ratio had no significant effect on astrocyte or microglia number or cell death in the dentate gyrus. These results suggest that supplementation of PUFAs may delay aging effects on cognitive function in unchallenged mature adult C57BL/6 mice. This effect is possibly induced by increasing neuronal progenitor proliferation and reducing TNF-α.

  9. Long-term omega-3 supplementation modulates behavior, hippocampal fatty acid concentration, neuronal progenitor proliferation and central TNF-α expression in 7 month old unchallenged mice

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    Trent eGrundy

    2014-11-01

    Full Text Available Dietary polyunsaturated fatty acid (PUFA manipulation is being investigated as a potential therapeutic supplement to reduce the risk of developing age-related cognitive decline (ARCD. Animal studies suggest that high omega (Ω-3 and low Ω-6 dietary content reduces cognitive decline by decreasing central nervous system (CNS inflammation and modifying neuroimmune activity. However, no previous studies have investigated the long term effects of Ω-3 and Ω-6 dietary levels in healthy aging mice leaving the important question about the preventive effects of Ω-3 and Ω-6 on behavior and underlying molecular pathways unaddressed. We aimed to investigate the efficacy of long-term Ω-3 and Ω-6 PUFA dietary supplementation in mature adult C57BL/6 mice. We measured the effect of low, medium and high Ω-3:Ω-6 dietary ratio, given from the age of 3 to 7 months, on anxiety and cognition-like behavior, hippocampal tissue expression of TNF-α, markers of neuronal progenitor proliferation and gliogenesis and serum cytokine concentration. Our results show that a higher Ω-3:Ω-6 PUFA diet ratio increased hippocampal PUFA, increased anxiety, improved hippocampal dependent spatial memory and reduced hippocampal TNF-α levels compared to a low Ω-3:Ω-6 diet. Furthermore, serum TNF-α concentration was reduced in the higher Ω-3:Ω-6 PUFA ratio supplementation group while expression of the neuronal progenitor proliferation markers KI67 and doublecortin (DCX was increased in the dentate gyrus as opposed to the low Ω-3:Ω-6 group. Conversely, Ω-3:Ω-6 dietary PUFA ratio had no significant effect on astrocyte or microglia number or cell death in the dentate gyrus. These results suggest that supplementation of PUFAs may delay ageing effects on cognitive function in unchallenged mature adult C57BL/6 mice. This effect is possibly induced by increasing neuronal progenitor proliferation and reducing TNF-α.

  10. Lengthening the G(1) phase of neural progenitor cells is concurrent with an increase of symmetric neuron generating division after stroke.

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    Zhang, Rui L; Zhang, Zheng G; Roberts, Cynthia; LeTourneau, Yvonne; Lu, Mei; Zhang, Li; Wang, Ying; Chopp, Michael

    2008-03-01

    The proportion of neural progenitors that remain in (P fraction) and exit from (Q fraction) the cell cycle determines the degree of neurogenesis. Using S-phase labeling with 5-bromo-2'-deoxyuridine and a double nucleoside analog-labeling scheme, we measured the cell-cycle kinetics of neural progenitors and estimated the proportion of P and Q fractions in the subventricular zone (SVZ) of adult rats subjected to stroke. Stroke increased SVZ cell proliferation, starting 2 days, reaching a maximum 4 and 7 days after stroke. The cell-cycle length (T(C)) of SVZ cells changed dynamically over a period of 2 to 14 days after stroke, with the shortest length of 11 h at 2 days after stroke. The reduction of the T(C) resulted from a decrease of the G(1) phase because the G(2), M, and S phases were unchanged. In addition, during this period, reduction of the G(1) phase was concomitant with an increase in the P fraction, whereas an augmentation of the Q fraction was associated with lengthening of the G(1) phase. Furthermore, approximately 90% of cells that exited the cell cycle were neurons and the population of a pair of dividing daughter cells with a neuronal marker increased from 9% at 2 days to 26% at 14 days after stroke. These data suggest that stroke triggers early expansion of the progenitor pool via shortening the cell-cycle length and retaining daughter cells within the cell cycle, and the lengthening of G(1) leads to daughter cells exiting the cell cycle and differentiating into neurons.

  11. Three-dimensional culture of single embryonic stem-derived neural/stem progenitor cells in fibrin hydrogels: neuronal network formation and matrix remodelling.

    Science.gov (United States)

    Bento, Ana R; Quelhas, Pedro; Oliveira, Maria J; Pêgo, Ana P; Amaral, Isabel F

    2016-12-29

    In an attempt to improve the efficacy of neural stem/progenitor cell (NSPC) based therapies, fibrin hydrogels are being explored to provide a favourable microenvironment for cell survival and differentiation following transplantation. In the present work, the ability of fibrin to support the survival, proliferation, and neuronal differentiation of NSPCs derived from embryonic stem (ES) cells under monolayer culture was explored. Single mouse ES-NSPCs were cultured within fibrin (fibrinogen concentration: 6 mg/ml) under neuronal differentiation conditions up to 14 days. The ES-NSPCs retained high cell viability and proliferated within small-sized spheroids. Neuronal differentiation was confirmed by an increase in the levels of βIII-tubulin and NF200 over time. At day 14, cell-matrix constructs mainly comprised NSPCs and neurons (46.5% βIII-tubulin(+) cells). Gamma-aminobutyric acid (GABA)ergic and dopaminergic/noradrenergic neurons were also observed, along with a network of synaptic proteins. The ES-NSPCs expressed matriptase and secreted MMP-2/9, with MMP-2 activity increasing along time. Fibronectin, laminin and collagen type IV deposition was also detected. Fibrin gels prepared with higher fibrinogen concentrations (8/10 mg/ml) were less permissive to neurite extension and neuronal differentiation, possibly owing to their smaller pore area and higher rigidity. Overall, it is shown that ES-NSPCs within fibrin are able to establish neuronal networks and to remodel fibrin through MMP secretion and extracellular matrix (ECM) deposition. This three-dimensional (3D) culture system was also shown to support cell viability, neuronal differentiation and ECM deposition of human ES-NSPCs. The settled 3D platform is expected to constitute a valuable tool to develop fibrin-based hydrogels for ES-NSPC delivery into the injured central nervous system. Copyright © 2016 John Wiley & Sons, Ltd.

  12. Differential regulation of the zebrafish orthopedia1 gene during fate determination of diencephalic neurons

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    Tarallo Raffaella

    2006-10-01

    Full Text Available Abstract Background The homeodomain transcription factor Orthopedia (Otp is essential in restricting the fate of multiple classes of secreting neurons in the neuroendocrine hypothalamus of vertebrates. However, there is little information on the intercellular factors that regulate Otp expression during development. Results Here, we identified two otp orthologues in zebrafish (otp1 and otp2 and explored otp1 in the context of the morphogenetic pathways that specify neuroectodermal regions. During forebrain development, otp1 is expressed in anterior groups of diencephalic cells, positioned in the preoptic area (PO (anterior alar plate and the posterior tuberculum (PT (posterior basal plate. The latter structure is characterized by Tyrosine Hydroxylase (TH-positive cells, suggesting a role for otp1 in the lineage restriction of catecholaminergic (CA neurons. Disruptions of Hedgehog (HH and Fibroblast Growth Factor (FGF pathways point to the ability of SHH protein to trigger otp1 expression in PO presumptive neuroblasts, with the attenuating effect of Dzip1 and FGF8. In addition, our data disclose otp1 as a determinant of CA neurons in the PT, where otp1 activity is strictly dependent on Nodal signaling and it is not responsive to SHH and FGF. Conclusion In this study, we pinpoint the evolutionary importance of otp1 transcription factor in cell states of the diencephalon anlage and early neuronal progenitors. Furthermore, our data indicate that morphogenetic mechanisms differentially regulate otp1 expression in alar and basal plates.

  13. Role of ERK1/2, Akt, and PLCy pathways in proliferation and neuronal differentiation in the adult rat spinal cord neural stem/progenitor cell culture

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    Wai Si eChan

    2013-08-01

    Full Text Available Proliferation of endogenous neural stem/progenitor cells (NSPCs has been identified in both normal and injured adult mammalian spinal cord. Yet the signaling mechanisms underlying the regulation of adult spinal cord NSPCs proliferation and commitment toward a neuronal lineage remain undefined. In this study, the role of three growth factor-mediated signaling pathways in proliferation and neuronal differentiation was examined. Adult spinal cord NSPCs were enriched in the presence of fibroblast growth factor 2 (FGF2. We observed an increase in the number of cells expressing the microtubule-associated protein 2 (MAP2 over time, indicating neuronal differentiation in the culture. Inhibition of the mitogen-activated protein kinase or extracellular signal-regulated kinase (ERK kinase 1 and 2/ERK 1 and 2 (MEK/ERK1/2 or the phosphoinositide 3-kinase (PI3K/Akt pathways suppressed active proliferation in adult spinal cord NSPC cultures; whereas neuronal differentiation was negatively affected only when the ERK1/2 pathway was inhibited. Inhibition of the phospholipase C gamma (PLCy pathway did not affect proliferation or neuronal differentiation. Finally, we demonstrated that the blockade of either the ERK1/2 or PLCy signaling pathways reduced neurite branching of MAP2+ cells derived from the NSPC cultures. Many of the MAP2+ cells expressed synaptophysin and had a glutamatergic phenotype, indicating that over time adult spinal cord NSPCs had differentiated into mostly glutamatergic neurons. Our work provides new information regarding the contribution of these pathways to the proliferation and neuronal differentiation of NSPCs derived from adult spinal cord cultures, and emphasizes that the contribution of these pathways is dependent on the origin of the NSPCs.

  14. NF1 regulation of RAS/ERK signaling is required for appropriate granule neuron progenitor expansion and migration in cerebellar development.

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    Sanchez-Ortiz, Efrain; Cho, Woosung; Nazarenko, Inga; Mo, Wei; Chen, Jian; Parada, Luis F

    2014-11-01

    Cerebellar development is regulated by a coordinated spatiotemporal interplay between granule neuron progenitors (GNPs), Purkinje neurons, and glia. Abnormal development can trigger motor deficits, and more recent data indicate important roles in aspects of memory, behavior, and autism spectrum disorders (ASDs). Germline mutation in the NF1 tumor suppressor gene underlies Neurofibromatosis type 1, a complex disease that enhances susceptibility to certain cancers and neurological disorders, including intellectual deficits and ASD. The NF1 gene encodes for neurofibromin, a RAS GTPase-activating protein, and thus negatively regulates the RAS signaling pathway. Here, using mouse models to direct conditional NF1 ablation in either embryonic cerebellar progenitors or neonatal GNPs, we show that neurofibromin is required for appropriate development of cerebellar folia layering and structure. Remarkably, neonatal administration of inhibitors of the ERK pathway reversed the morphological defects. Thus, our findings establish a critical cell-autonomous role for the NF1-RAS-ERK pathway in the appropriate regulation of cerebellar development and provide a basis for using neonatal ERK inhibitor-based therapies to treat NF1-induced cerebellar disorders.

  15. VCE-003.2, a novel cannabigerol derivative, enhances neuronal progenitor cell survival and alleviates symptomatology in murine models of Huntington’s disease

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    Díaz-Alonso, Javier; Paraíso-Luna, Juan; Navarrete, Carmen; del Río, Carmen; Cantarero, Irene; Palomares, Belén; Aguareles, José; Fernández-Ruiz, Javier; Bellido, María Luz; Pollastro, Federica; Appendino, Giovanni; Calzado, Marco A.; Galve-Roperh, Ismael; Muñoz, Eduardo

    2016-01-01

    Cannabinoids have shown to exert neuroprotective actions in animal models by acting at different targets including canonical cannabinoid receptors and PPARγ. We previously showed that VCE-003, a cannabigerol (CBG) quinone derivative, is a novel neuroprotective and anti-inflammatory cannabinoid acting through PPARγ. We have now generated a non-thiophilic VCE-003 derivative named VCE-003.2 that preserves the ability to activate PPARγ and analyzed its neuroprotective activity. This compound exerted a prosurvival action in progenitor cells during neuronal differentiation, which was prevented by a PPARγ antagonist, without affecting neural progenitor cell proliferation. In addition, VCE-003.2 attenuated quinolinic acid (QA)-induced cell death and caspase-3 activation and also reduced mutant huntingtin aggregates in striatal cells. The neuroprotective profile of VCE-003.2 was analyzed using in vivo models of striatal neurodegeneration induced by QA and 3-nitropropionic acid (3NP) administration. VCE-003.2 prevented medium spiny DARPP32+ neuronal loss in these Huntington’s-like disease mice models improving motor deficits, reactive astrogliosis and microglial activation. In the 3NP model VCE-003.2 inhibited the upregulation of proinflammatory markers and improved antioxidant defenses in the brain. These data lead us to consider VCE-003.2 to have high potential for the treatment of Huntington’s disease (HD) and other neurodegenerative diseases with neuroinflammatory traits. PMID:27430371

  16. VCE-003.2, a novel cannabigerol derivative, enhances neuronal progenitor cell survival and alleviates symptomatology in murine models of Huntington's disease.

    Science.gov (United States)

    Díaz-Alonso, Javier; Paraíso-Luna, Juan; Navarrete, Carmen; Del Río, Carmen; Cantarero, Irene; Palomares, Belén; Aguareles, José; Fernández-Ruiz, Javier; Bellido, María Luz; Pollastro, Federica; Appendino, Giovanni; Calzado, Marco A; Galve-Roperh, Ismael; Muñoz, Eduardo

    2016-07-19

    Cannabinoids have shown to exert neuroprotective actions in animal models by acting at different targets including canonical cannabinoid receptors and PPARγ. We previously showed that VCE-003, a cannabigerol (CBG) quinone derivative, is a novel neuroprotective and anti-inflammatory cannabinoid acting through PPARγ. We have now generated a non-thiophilic VCE-003 derivative named VCE-003.2 that preserves the ability to activate PPARγ and analyzed its neuroprotective activity. This compound exerted a prosurvival action in progenitor cells during neuronal differentiation, which was prevented by a PPARγ antagonist, without affecting neural progenitor cell proliferation. In addition, VCE-003.2 attenuated quinolinic acid (QA)-induced cell death and caspase-3 activation and also reduced mutant huntingtin aggregates in striatal cells. The neuroprotective profile of VCE-003.2 was analyzed using in vivo models of striatal neurodegeneration induced by QA and 3-nitropropionic acid (3NP) administration. VCE-003.2 prevented medium spiny DARPP32(+) neuronal loss in these Huntington's-like disease mice models improving motor deficits, reactive astrogliosis and microglial activation. In the 3NP model VCE-003.2 inhibited the upregulation of proinflammatory markers and improved antioxidant defenses in the brain. These data lead us to consider VCE-003.2 to have high potential for the treatment of Huntington's disease (HD) and other neurodegenerative diseases with neuroinflammatory traits.

  17. Zebrafish cyclin Dx is required for development of motor neuron progenitors, and its expression is regulated by hypoxia-inducible factor 2α.

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    Lien, Huang-Wei; Yuan, Rey-Yue; Chou, Chih-Ming; Chen, Yi-Chung; Hung, Chin-Chun; Hu, Chin-Hwa; Hwang, Sheng-Ping L; Hwang, Pung-Pung; Shen, Chia-Ning; Chen, Chih-Lung; Cheng, Chia-Hsiung; Huang, Chang-Jen

    2016-06-21

    Cyclins play a central role in cell-cycle regulation; in mammals, the D family of cyclins consists of cyclin D1, D2, and D3. In Xenopus, only homologs of cyclins D1 and D2 have been reported, while a novel cyclin, cyclin Dx (ccndx), was found to be required for the maintenance of motor neuron progenitors during embryogenesis. It remains unknown whether zebrafish possess cyclin D3 or cyclin Dx. In this study, we identified a zebrafish ccndx gene encoding a protein which can form a complex with Cdk4. Through whole-mount in situ hybridization, we observed that zccndx mRNA is expressed in the motor neurons of hindbrain and spinal cord during development. Analysis of a 4-kb promoter sequence of the zccndx gene revealed the presence of HRE sites, which can be regulated by HIF2α. Morpholino knockdown of zebrafish Hif2α and cyclin Dx resulted in the abolishment of isl1 and oligo2 expression in the precursors of motor neurons, and also disrupted axon growth. Overexpression of cyclin Dx mRNA in Hif2α morphants partially rescued zccndx expression. Taken together, our data indicate that zebrafish cyclin Dx plays a role in maintaining the precursors of motor neurons.

  18. Caveolin-1 plays a crucial role in inhibiting neuronal differentiation of neural stem/progenitor cells via VEGF signaling-dependent pathway.

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    Yue Li

    Full Text Available In the present study, we aim to elucidate the roles of caveolin-1(Cav-1, a 22 kDa protein in plasma membrane invaginations, in modulating neuronal differentiation of neural progenitor cells (NPCs. In the hippocampal dentate gyrus, we found that Cav-1 knockout mice revealed remarkably higher levels of vascular endothelial growth factor (VEGF and the more abundant formation of newborn neurons than wild type mice. We then studied the potential mechanisms of Cav-1 in modulating VEGF signaling and neuronal differentiation in isolated cultured NPCs under normoxic and hypoxic conditions. Hypoxic embryonic rat NPCs were exposed to 1% O₂ for 24 h and then switched to 21% O₂ for 1, 3, 7 and 14 days whereas normoxic NPCs were continuously cultured with 21% O₂. Compared with normoxic NPCs, hypoxic NPCs had down-regulated expression of Cav-1 and up-regulated VEGF expression and p44/42MAPK phosphorylation, and enhanced neuronal differentiation. We further studied the roles of Cav-1 in inhibiting neuronal differentiation by using Cav-1 scaffolding domain peptide and Cav-1-specific small interfering RNA. In both normoxic and hypoxic NPCs, Cav-1 peptide markedly down-regulated the expressions of VEGF and flk1, decreased the phosphorylations of p44/42MAPK, Akt and Stat3, and inhibited neuronal differentiation, whereas the knockdown of Cav-1 promoted the expression of VEGF, phosphorylations of p44/42MAPK, Akt and Stat3, and stimulated neuronal differentiation. Moreover, the enhanced phosphorylations of p44/42MAPK, Akt and Stat3, and neuronal differentiation were abolished by co-treatment of VEGF inhibitor V1. These results provide strong evidence to prove that Cav-1 can inhibit neuronal differentiation via down-regulations of VEGF, p44/42MAPK, Akt and Stat3 signaling pathways, and that VEGF signaling is a crucial target of Cav-1. The hypoxia-induced down-regulation of Cav-1 contributes to enhanced neuronal differentiation in NPCs.

  19. Stem/progenitor cells in the cerebral cortex of the human preterm: a resource for an endogenous regenerative neuronal medicine?

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    Laura Vinci

    2016-04-01

    Full Text Available The development of the central nervous system represents a very delicate period of embryogenesis. Premature interruption of neurogenesis in human preterm newborns can lead to motor deficits, including cerebral palsy, and significant cognitive, behavioral or sensory deficits in childhood. Preterm infants also have a higher risk of developing neurodegenerative diseases later in life. In the last decade, great importance has been given to stem/progenitor cells and their possible role in the development and treatment of several neurological disorders. Several studies, mainly carried out on experimental models, evidenced that immunohistochemistry may allow the identification of different neural and glial precursors inside the developing cerebral cortex. However, only a few studies have been performed on markers of human stem cells in the embryonic period.This review aims at illustrating the importance of stem/progenitor cells in cerebral cortex during pre- and post-natal life. Defining the immunohistochemical markers of stem/progenitor cells in the human cerebral cortex during development may be important to develop an “endogenous” target therapy in the perinatal period. Proceedings of the 2nd International Course on Perinatal Pathology (part of the 11th International Workshop on Neonatology · October 26th-31st, 2015 · Cagliari (Italy · October 31st, 2015 · Stem cells: present and future Guest Editors: Gavino Faa, Vassilios Fanos, Antonio Giordano

  20. Gene expression profile of neuronal progenitor cells derived from hESCs: activation of chromosome 11p15.5 and comparison to human dopaminergic neurons.

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    William J Freed

    Full Text Available BACKGROUND: We initiated differentiation of human embryonic stem cells (hESCs into dopamine neurons, obtained a purified population of neuronal precursor cells by cell sorting, and determined patterns of gene transcription. METHODOLOGY: Dopaminergic differentiation of hESCs was initiated by culturing hESCs with a feeder layer of PA6 cells. Differentiating cells were then sorted to obtain a pure population of PSA-NCAM-expressing neuronal precursors, which were then analyzed for gene expression using Massive Parallel Signature Sequencing (MPSS. Individual genes as well as regions of the genome which were activated were determined. PRINCIPAL FINDINGS: A number of genes known to be involved in the specification of dopaminergic neurons, including MSX1, CDKN1C, Pitx1 and Pitx2, as well as several novel genes not previously associated with dopaminergic differentiation, were expressed. Notably, we found that a specific region of the genome located on chromosome 11p15.5 was highly activated. This region contains several genes which have previously been associated with the function of dopaminergic neurons, including the gene for tyrosine hydroxylase (TH, the rate-limiting enzyme in catecholamine biosynthesis, IGF2, and CDKN1C, which cooperates with Nurr1 in directing the differentiation of dopaminergic neurons. Other genes in this region not previously recognized as being involved in the functions of dopaminergic neurons were also activated, including H19, TSSC4, and HBG2. IGF2 and CDKN1C were also found to be highly expressed in mature human TH-positive dopamine neurons isolated from human brain samples by laser capture. CONCLUSIONS: The present data suggest that the H19-IGF2 imprinting region on chromosome 11p15.5 is involved in the process through which undifferentiated cells are specified to become neuronal precursors and/or dopaminergic neurons.

  1. In vivo and in vitro treatment with edaravone promotes proliferation of neural progenitor cells generated following neuronal loss in the mouse dentate gyrus.

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    Kikuta, Maho; Shiba, Tatsuo; Yoneyama, Masanori; Kawada, Koichi; Yamaguchi, Taro; Hinoi, Eiichi; Yoneda, Yukio; Ogita, Kiyokazu

    2013-01-01

    Edaravone is clinically used in Japan for treatment of patients with acute cerebral infarction. To clarify the effect of edaravone on neurogenesis in the hippocampus following neuronal injury in the hippocampal dentate gyrus, we investigated the effect of in vitro and in vivo treatment with edaravone on the proliferation of neural stem/progenitor cells prepared from the mouse dentate gyrus damaged by trimethyltin (TMT). Histological assessment revealed the presence of large number of nestin(+) cells in the dentate gyrus on days 3 - 5 post-TMT treatment. We prepared cells from the dentate gyrus of naïve, TMT-treated mice or TMT/edaravone-treated mice. The cells obtained from the dentate gyrus of TMT-treated animals were capable of BrdU incorporation and neurosphere formation when cultured in the presence of growth factors. The TMT-treated group had a larger number of nestin(+) cells and nestin(+)GFAP(+) cells than the naïve one. Under the culture condition used, sustained exposure of the cells from the damaged dentate gyrus to edaravone at 10(-11) and 10(-8) M promoted the proliferation of nestin(+) cells. The systemic in vivo treatment with edaravone for 2 days produced a significant increase in the number of nestin(+) cells among the cells prepared from the dentate gyrus on day 4 post-TMT treatment, and as well as one in the number of neurospheres formed from these cells in the culture. Taken together, our data indicated that edaravone had the ability to promote the proliferation of neural stem/progenitor cells generated following neuronal damage in the dentate gyrus.

  2. Orthotopic transplantation of immortalized mesencephalic progenitors (CSM14.1 cells) into the substantia nigra of hemiparkinsonian rats induces neuronal differentiation and motoric improvement.

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    Haas, Stefan Jean-Pierre; Petrov, Stanislav; Kronenberg, Golo; Schmitt, Oliver; Wree, Andreas

    2008-01-01

    Neural progenitor cell grafting is a promising therapeutic option in the treatment of Parkinson's disease. In previous experiments we grafted temperature-sensitive immortalized CSM14.1 cells, derived from the ventral mesencephalon of E14-rats, bilaterally in the caudate putamen of adult hemiparkinsonian rats. In these studies we were not able to demonstrate either a therapeutic improvement or neuronal differentiation of transplanted cells. Here we examined whether CSM14.1 cells grafted bilaterally orthotopically in the substantia nigra of hemiparkinsonian rats have the potential to differentiate into dopaminergic neurons. Adult male rats received 6-hydroxydopamine into the right medial forebrain bundle, and successful lesions were evaluated with apomorphine-induced rotations 12 days after surgery. Two weeks after a successful lesion the animals received bilateral intranigral grafts consisting of either about 50 000 PKH26-labelled undifferentiated CSM14.1 cells (n = 16) or a sham-graft (n = 9). Rotations were evaluated 3, 6, 9 and 12 weeks post-grafting. Animals were finally perfused with 4% paraformaldehyde. Cryoprotected brain slices were prepared for immunohistochemistry using the freeze-thaw technique to preserve PKH26-labelling. Slices were immunostained against neuronal epitopes (NeuN, tyrosine hydroxylase) or glial fibrillary acidic protein. The CSM14.1-cell grafts significantly reduced the apomorphine-induced rotations 12 weeks post-grafting compared to the sham-grafts (P < 0.05). There was an extensive mediolateral migration (400-700 microm) of the PKH26-labelled cells within the host substantia nigra. Colocalization with NeuN or glial fibrillary acidic protein in transplanted cells was confirmed with confocal microscopy. No tyrosine hydroxylase-immunoreactive grafted cells were detectable. The therapeutic effect of the CSM14.1 cells could be explained either by their glial cell-derived neurotrophic factor-expression or their neural differentiation with

  3. Dimethyl Fumarate Protects Neural Stem/Progenitor Cells and Neurons from Oxidative Damage through Nrf2-ERK1/2 MAPK Pathway

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    Qin Wang

    2015-06-01

    Full Text Available Multiple sclerosis (MS is the most common multifocal inflammatory demyelinating disease of the central nervous system (CNS. Due to the progressive neurodegenerative nature of MS, developing treatments that exhibit direct neuroprotective effects are needed. Tecfidera™ (BG-12 is an oral formulation of the fumaric acid esters (FAE, containing the active metabolite dimethyl fumarate (DMF. Although BG-12 showed remarkable efficacy in lowering relapse rates in clinical trials, its mechanism of action in MS is not yet well understood. In this study, we reported the potential neuroprotective effects of dimethyl fumarate (DMF on mouse and rat neural stem/progenitor cells (NPCs and neurons. We found that DMF increased the frequency of the multipotent neurospheres and the survival of NPCs following oxidative stress with hydrogen peroxide (H2O2 treatment. In addition, utilizing the reactive oxygen species (ROS assay, we showed that DMF reduced ROS production induced by H2O2. DMF also decreased oxidative stress-induced apoptosis. Using motor neuron survival assay, DMF significantly promoted survival of motor neurons under oxidative stress. We further analyzed the expression of oxidative stress-induced genes in the NPC cultures and showed that DMF increased the expression of transcription factor nuclear factor-erythroid 2-related factor 2 (Nrf2 at both levels of RNA and protein. Furthermore, we demonstrated the involvement of Nrf2-ERK1/2 MAPK pathway in DMF-mediated neuroprotection. Finally, we utilized SuperArray gene screen technology to identify additional anti-oxidative stress genes (Gstp1, Sod2, Nqo1, Srxn1, Fth1. Our data suggests that analysis of anti-oxidative stress mechanisms may yield further insights into new targets for treatment of multiple sclerosis (MS.

  4. Apoptosis-inducing factor downregulation increased neuronal progenitor, but not stem cell, survival in the neonatal hippocampus after cerebral hypoxia-ischemia

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    Sun Yanyan

    2012-04-01

    Full Text Available Abstract Background A considerable proportion of all newly generated cells in the hippocampus will die before becoming fully differentiated, both under normal and pathological circumstances. The caspase-independent apoptosis-inducing factor (AIF has not been investigated previously in this context. Results Postnatal day 8 (P8 harlequin (Hq mutant mice, expressing lower levels of AIF, and wild type littermates were injected with BrdU once daily for two days to label newborn cells. On P10 mice were subjected to hypoxia-ischemia (HI and their brains were analyzed 4 h, 24 h or 4 weeks later. Overall tissue loss was 63.5% lower in Hq mice 4 weeks after HI. Short-term survival (4 h and 24 h of labeled cells in the subgranular zone was neither affected by AIF downregulation, nor by HI. Long-term (4 weeks survival of undifferentiated, BLBP-positive stem cells was reduced by half after HI, but this was not changed by AIF downregulation. Neurogenesis, however, as judged by BrdU/NeuN double labeling, was reduced by half after HI in wild type mice but preserved in Hq mice, indicating that primarily neural progenitors and neurons were protected. A wave of cell death started early after HI in the innermost layers of the granule cell layer (GCL and moved outward, such that 24 h after HI dying cells could be detected in the entire GCL. Conclusions These findings demonstrate that AIF downregulation provides not only long-term overall neuroprotection after HI, but also protects neural progenitor cells, thereby rescuing hippocampal neurogenesis.

  5. RAF kinase activity regulates neuroepithelial cell proliferation and neuronal progenitor cell differentiation during early inner ear development.

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    Marta Magariños

    Full Text Available BACKGROUND: Early inner ear development requires the strict regulation of cell proliferation, survival, migration and differentiation, coordinated by the concerted action of extrinsic and intrinsic factors. Deregulation of these processes is associated with embryonic malformations and deafness. We have shown that insulin-like growth factor I (IGF-I plays a key role in embryonic and postnatal otic development by triggering the activation of intracellular lipid and protein kinases. RAF kinases are serine/threonine kinases that regulate the highly conserved RAS-RAF-MEK-ERK signaling cascade involved in transducing the signals from extracellular growth factors to the nucleus. However, the regulation of RAF kinase activity by growth factors during development is complex and still not fully understood. METHODOLOGY/PRINCIPAL FINDINGS: By using a combination of qRT-PCR, Western blotting, immunohistochemistry and in situ hybridization, we show that C-RAF and B-RAF are expressed during the early development of the chicken inner ear in specific spatiotemporal patterns. Moreover, later in development B-RAF expression is associated to hair cells in the sensory patches. Experiments in ex vivo cultures of otic vesicle explants demonstrate that the influence of IGF-I on proliferation but not survival depends on RAF kinase activating the MEK-ERK phosphorylation cascade. With the specific RAF inhibitor Sorafenib, we show that blocking RAF activity in organotypic cultures increases apoptosis and diminishes the rate of cell proliferation in the otic epithelia, as well as severely impairing neurogenesis of the acoustic-vestibular ganglion (AVG and neuron maturation. CONCLUSIONS/SIGNIFICANCE: We conclude that RAF kinase activity is essential to establish the balance between cell proliferation and death in neuroepithelial otic precursors, and for otic neuron differentiation and axonal growth at the AVG.

  6. Ascl3 marks adult progenitor cells of the mouse salivary gland.

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    Rugel-Stahl, Anastasia; Elliott, Marilyn E; Ovitt, Catherine E

    2012-05-01

    The Ascl3 transcription factor marks a subset of salivary gland duct cells present in the three major salivary glands of the mouse. In vivo, these cells generate both duct and secretory acinar cell descendants. Here, we have analyzed whether Ascl3-expressing cells retain this multipotent lineage potential in adult glands. Cells isolated from mouse salivary glands were cultured in vitro as non-adherent spheres. Lineage tracing of the Ascl3-expressing cells within the spheres demonstrates that Ascl3+ cells isolated from adult glands remain multipotent, generating both duct and acinar cell types in vitro. Furthermore, we demonstrate that the progenitor cells characterized by Keratin 5 expression are an independent population from Ascl3+ progenitor cells. We conclude that the Ascl3+ cells are intermediate lineage-restricted progenitor cells of the adult salivary glands.

  7. The development of innate lymphoid cells requires TOX-dependent generation of a common innate lymphoid cell progenitor.

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    Seehus, Corey R; Aliahmad, Parinaz; de la Torre, Brian; Iliev, Iliyan D; Spurka, Lindsay; Funari, Vincent A; Kaye, Jonathan

    2015-06-01

    Diverse innate lymphoid cell (ILC) subtypes have been defined on the basis of effector function and transcription factor expression. ILCs derive from common lymphoid progenitors, although the transcriptional pathways that lead to ILC-lineage specification remain poorly characterized. Here we found that the transcriptional regulator TOX was required for the in vivo differentiation of common lymphoid progenitors into ILC lineage-restricted cells. In vitro modeling demonstrated that TOX deficiency resulted in early defects in the survival or proliferation of progenitor cells, as well as ILC differentiation at a later stage. In addition, comparative transcriptome analysis of bone marrow progenitors revealed that TOX-deficient cells failed to upregulate many genes of the ILC program, including genes that are targets of Notch, which indicated that TOX is a key determinant of early specification to the ILC lineage.

  8. Adipogenic placenta-derived mesenchymal stem cells are not lineage restricted by withdrawing extrinsic factors: developing a novel visual angle in stem cell biology.

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    Hu, C; Cao, H; Pan, X; Li, J; He, J; Pan, Q; Xin, J; Yu, X; Li, J; Wang, Y; Zhu, D; Li, L

    2016-03-17

    Current evidence implies that differentiated bone marrow mesenchymal stem cells (BMMSCs) can act as progenitor cells and transdifferentiate across lineage boundaries. However, whether this unrestricted lineage has specificities depending on the stem cell type is unknown. Placental-derived mesenchymal stem cells (PDMSCs), an easily accessible and less invasive source, are extremely useful materials in current stem cell therapies. No studies have comprehensively analyzed the transition in morphology, surface antigens, metabolism and multilineage potency of differentiated PDMSCs after their dedifferentiation. In this study, we showed that after withdrawing extrinsic factors, adipogenic PDMSCs reverted to a primitive cell population and retained stem cell characteristics. The mitochondrial network during differentiation and dedifferentiation may serve as a marker of absent or acquired pluripotency in various stem cell models. The new population proliferated faster than unmanipulated PDMSCs and could be differentiated into adipocytes, osteocytes and hepatocytes. The cell adhesion molecules (CAMs) signaling pathway and extracellular matrix (ECM) components modulate cell behavior and enable the cells to proliferate or differentiate during the differentiation, dedifferentiation and redifferentiation processes in our study. These observations indicate that the dedifferentiated PDMSCs are distinguishable from the original PDMSCs and may serve as a novel source in stem cell biology and cell-based therapeutic strategies. Furthermore, whether PDMSCs differentiated into other lineages can be dedifferentiated to a primitive cell population needs to be investigated.

  9. Adipogenic placenta-derived mesenchymal stem cells are not lineage restricted by withdrawing extrinsic factors: developing a novel visual angle in stem cell biology

    Science.gov (United States)

    Hu, C; Cao, H; Pan, X; Li, J; He, J; Pan, Q; Xin, J; Yu, X; Li, J; Wang, Y; Zhu, D; Li, L

    2016-01-01

    Current evidence implies that differentiated bone marrow mesenchymal stem cells (BMMSCs) can act as progenitor cells and transdifferentiate across lineage boundaries. However, whether this unrestricted lineage has specificities depending on the stem cell type is unknown. Placental-derived mesenchymal stem cells (PDMSCs), an easily accessible and less invasive source, are extremely useful materials in current stem cell therapies. No studies have comprehensively analyzed the transition in morphology, surface antigens, metabolism and multilineage potency of differentiated PDMSCs after their dedifferentiation. In this study, we showed that after withdrawing extrinsic factors, adipogenic PDMSCs reverted to a primitive cell population and retained stem cell characteristics. The mitochondrial network during differentiation and dedifferentiation may serve as a marker of absent or acquired pluripotency in various stem cell models. The new population proliferated faster than unmanipulated PDMSCs and could be differentiated into adipocytes, osteocytes and hepatocytes. The cell adhesion molecules (CAMs) signaling pathway and extracellular matrix (ECM) components modulate cell behavior and enable the cells to proliferate or differentiate during the differentiation, dedifferentiation and redifferentiation processes in our study. These observations indicate that the dedifferentiated PDMSCs are distinguishable from the original PDMSCs and may serve as a novel source in stem cell biology and cell-based therapeutic strategies. Furthermore, whether PDMSCs differentiated into other lineages can be dedifferentiated to a primitive cell population needs to be investigated. PMID:26986509

  10. Leukemia inhibitory factor (LIF) enhances MAP2 + and HUC/D + neurons and influences neurite extension during differentiation of neural progenitors derived from human embryonic stem cells.

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    Leukemia Inhibitory Factor (L1F), a member of the Interleukin 6 cytokine family, has a role in differentiation of Human Neural Progenitor (hNP) cells in vitro. hNP cells, derived from Human Embryonic Stem (hES) cells, have an unlimited capacity for self-renewal in monolayer cultu...

  11. Leukemia inhibitory factor (LIF) enhances MAP2 + and HUC/D + neurons and influences neurite extension during differentiation of neural progenitors derived from human embryonic stem cells.

    Science.gov (United States)

    Leukemia Inhibitory Factor (L1F), a member of the Interleukin 6 cytokine family, has a role in differentiation of Human Neural Progenitor (hNP) cells in vitro. hNP cells, derived from Human Embryonic Stem (hES) cells, have an unlimited capacity for self-renewal in monolayer cultu...

  12. Successful elimination of non-neural cells and unachievable elimination of glial cells by means of commonly used cell culture manipulations during differentiation of GFAP and SOX2 positive neural progenitors (NHA to neuronal cells

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    Krynska Barbara

    2008-07-01

    Full Text Available Abstract Background Although extensive research has been performed to control differentiation of neural stem cells – still, the response of those cells to diverse cell culture conditions often appears to be random and difficult to predict. To this end, we strived to obtain stabilized protocol of NHA cells differentiation – allowing for an increase in percentage yield of neuronal cells. Results Uncommitted GFAP and SOX2 positive neural progenitors – so-called, Normal Human Astrocytes (NHA were differentiated in different environmental conditions to: only neural cells consisted of neuronal [MAP2+, GFAP-] and glial [GFAP+, MAP2-] population, non-neural cells [CD44+, VIMENTIN+, FIBRONECTIN+, MAP2-, GFAP-, S100β-, SOX2-], or mixture of neural and non-neural cells. In spite of successfully increasing the percentage yield of glial and neuronal vs. non-neural cells by means of environmental changes, we were not able to increase significantly the percentage of neuronal (GABA-ergic and catecholaminergic over glial cells under several different cell culture testing conditions. Supplementing serum-free medium with several growth factors (SHH, bFGF, GDNF did not radically change the ratio between neuronal and glial cells – i.e., 1,1:1 in medium without growth factors and 1,4:1 in medium with GDNF, respectively. Conclusion We suggest that biotechnologists attempting to enrich in vitro neural cell cultures in one type of cells – such as that required for transplantology purposes, should consider the strong limiting influence of intrinsic factors upon extracellular factors commonly tested in cell culture conditions.

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

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    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.

  14. Use of "MGE enhancers" for labeling and selection of embryonic stem cell-derived medial ganglionic eminence (MGE progenitors and neurons.

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    Ying-Jiun J Chen

    Full Text Available The medial ganglionic eminence (MGE is an embryonic forebrain structure that generates the majority of cortical interneurons. MGE transplantation into specific regions of the postnatal central nervous system modifies circuit function and improves deficits in mouse models of epilepsy, Parkinson's disease, pain, and phencyclidine-induced cognitive deficits. Herein, we describe approaches to generate MGE-like progenitor cells from mouse embryonic stem (ES cells. Using a modified embryoid body method, we provided gene expression evidence that mouse ES-derived Lhx6(+ cells closely resemble immature interneurons generated from authentic MGE-derived Lhx6(+ cells. We hypothesized that enhancers that are active in the mouse MGE would be useful tools in detecting when ES cells differentiate into MGE cells. Here we demonstrate the utility of enhancer elements [422 (DlxI12b, Lhx6, 692, 1056, and 1538] as tools to mark MGE-like cells in ES cell differentiation experiments. We found that enhancers DlxI12b, 692, and 1538 are active in Lhx6-GFP(+ cells, while enhancer 1056 is active in Olig2(+ cells. These data demonstrate unique techniques to follow and purify MGE-like derivatives from ES cells, including GABAergic cortical interneurons and oligodendrocytes, for use in stem cell-based therapeutic assays and treatments.

  15. A novel neuron-enriched protein SDIM1 is down regulated in Alzheimer's brains and attenuates cell death induced by DNAJB4 over-expression in neuro-progenitor cells

    Directory of Open Access Journals (Sweden)

    Lei Joy X

    2011-01-01

    Full Text Available Abstract Background Molecular changes in multiple biological processes contribute to the development of chronic neurodegeneration such as late onset Alzheimer's disease (LOAD. To discover how these changes are reflected at the level of gene expression, we used a subtractive transcription-based amplification of mRNA procedure to identify novel genes that have altered expression levels in the brains of Alzheimer's disease (AD patients. Among the genes altered in expression level in AD brains was a transcript encoding a novel protein, SDIM1, that contains 146 amino acids, including a typical signal peptide and two transmembrane domains. Here we examined its biochemical properties and putative roles in neuroprotection/neurodegeneration. Results QRT-PCR analysis of additional AD and control post-mortem human brains showed that the SDIM1 transcript was indeed significantly down regulated in all AD brains. SDIM1 is more abundant in NT2 neurons than astrocytes and present throughout the cytoplasm and neural processes, but not in the nuclei. In NT2 neurons, it is highly responsive to stress conditions mimicking insults that may cause neurodegeneration in AD brains. For example, SDIM1 was significantly down regulated 2 h after oxygen-glucose deprivation (OGD, though had recovered 16 h later, and also appeared significantly up regulated compared to untreated NT2 neurons. Overexpression of SDIM1 in neuro-progenitor cells improved cells' ability to survive after injurious insults and its downregulation accelerated cell death induced by OGD. Yeast two-hybrid screening and co-immunoprecipitation approaches revealed, both in vitro and in vivo, an interaction between SDIM1 and DNAJB4, a heat shock protein hsp40 homolog, recently known as an enhancer of apoptosis that also interacts with the mu opioid receptor in human brain. Overexpression of DNAJB4 alone significantly reduced cell viability and SDIM1 co-overexpression was capable of attenuating the cell death

  16. Real time imaging of human progenitor neurogenesis.

    Directory of Open Access Journals (Sweden)

    Thomas M Keenan

    Full Text Available Human neural progenitors are increasingly being employed in drug screens and emerging cell therapies targeted towards neurological disorders where neurogenesis is thought to play a key role including developmental disorders, Alzheimer's disease, and depression. Key to the success of these applications is understanding the mechanisms by which neurons arise. Our understanding of development can provide some guidance but since little is known about the specifics of human neural development and the requirement that cultures be expanded in vitro prior to use, it is unclear whether neural progenitors obey the same developmental mechanisms that exist in vivo. In previous studies we have shown that progenitors derived from fetal cortex can be cultured for many weeks in vitro as undifferentiated neurospheres and then induced to undergo neurogenesis by removing mitogens and exposing them to supportive substrates. Here we use live time lapse imaging and immunocytochemical analysis to show that neural progenitors use developmental mechanisms to generate neurons. Cells with morphologies and marker profiles consistent with radial glia and recently described outer radial glia divide asymmetrically and symmetrically to generate multipolar intermediate progenitors, a portion of which express ASCL1. These multipolar intermediate progenitors subsequently divide symmetrically to produce CTIP2(+ neurons. This 3-cell neurogenic scheme echoes observations in rodents in vivo and in human fetal slice cultures in vitro, providing evidence that hNPCs represent a renewable and robust in vitro assay system to explore mechanisms of human neurogenesis without the continual need for fresh primary human fetal tissue. Knowledge provided by this and future explorations of human neural progenitor neurogenesis will help maximize the safety and efficacy of new stem cell therapies by providing an understanding of how to generate physiologically-relevant cell types that maintain their

  17. Prolonged Mitosis of Neural Progenitors Alters Cell Fate in the Developing Brain.

    Science.gov (United States)

    Pilaz, Louis-Jan; McMahon, John J; Miller, Emily E; Lennox, Ashley L; Suzuki, Aussie; Salmon, Edward; Silver, Debra L

    2016-01-06

    Embryonic neocortical development depends on balanced production of progenitors and neurons. Genetic mutations disrupting progenitor mitosis frequently impair neurogenesis; however, the link between altered mitosis and cell fate remains poorly understood. Here we demonstrate that prolonged mitosis of radial glial progenitors directly alters neuronal fate specification and progeny viability. Live imaging of progenitors from a neurogenesis mutant, Magoh(+/-), reveals that mitotic delay significantly correlates with preferential production of neurons instead of progenitors, as well as apoptotic progeny. Independently, two pharmacological approaches reveal a causal relationship between mitotic delay and progeny fate. As mitotic duration increases, progenitors produce substantially more apoptotic progeny or neurons. We show that apoptosis, but not differentiation, is p53 dependent, demonstrating that these are distinct outcomes of mitotic delay. Together our findings reveal that prolonged mitosis is sufficient to alter fates of radial glia progeny and define a new paradigm to understand how mitosis perturbations underlie brain size disorders such as microcephaly.

  18. Sequential activation of p75 and TrkB is involved in dendritic development of subventricular zone-derived neuronal progenitors in vitro.

    Science.gov (United States)

    Gascon, E; Vutskits, L; Zhang, H; Barral-Moran, M J; Kiss, P J; Mas, C; Kiss, J Z

    2005-01-01

    Dendritic arbor development of subventricular zone-derived interneurons is a critical step in their integration into functional circuits of the postnatal olfactory bulb. However, the mechanism and molecular control of this process remain unknown. In this study, we have developed a culture model where dendritic development of purified subventricular zone cells proceeds under serum-free conditions in the absence of added growth factors and non-neural cells. We demonstrate that the large majority of these cells in culture express GABA and elaborate dendritic arbors with spine-like protrusions but they do not possess axons. These neurons expressed receptors for neurotrophins including p75, TrkB and TrkC but not TrkA. Application of exogenous neurotrophins, including brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT3) and nerve growth factor (NGF), to cultures stimulated dendritic growth and led to more complex dendritic arbors during the initial 3 days in culture. Our results suggest that these effects are independent of Trk receptors and mediated by the p75/ceramide signaling pathway. We also show that brain-derived neurotrophic factor is the only neurotrophin that is able to influence late-phase dendritic development via TrkB receptor activation. These results suggest that dendritic arbor development of subventricular zone-derived cells may be regulated by neurotrophins through the activation of p75 and the TrkB receptor signaling pathways in a sequentially defined temporal pattern.

  19. Dopamine Receptor Antagonists Enhance Proliferation and Neurogenesis of Midbrain Lmx1a-expressing Progenitors

    OpenAIRE

    Eva Hedlund; Laure Belnoue; Spyridon Theofilopoulos; Carmen Salto; Chris Bye; Clare Parish; Qiaolin Deng; Banafsheh Kadkhodaei; Johan Ericson; Ernest Arenas; Thomas Perlmann; András Simon

    2016-01-01

    Degeneration of dopamine neurons in the midbrain causes symptoms of the movement disorder, Parkinson disease. Dopamine neurons are generated from proliferating progenitor cells localized in the embryonic ventral midbrain. However, it remains unclear for how long cells with dopamine progenitor character are retained and if there is any potential for reactivation of such cells after cessation of normal dopamine neurogenesis. We show here that cells expressing Lmx1a and other progenitor markers ...

  20. Regulation of the nascent brain vascular network by neural progenitors.

    Science.gov (United States)

    Santhosh, Devi; Huang, Zhen

    2015-11-01

    Neural progenitors are central players in the development of the brain neural circuitry. They not only produce the diverse neuronal and glial cell types in the brain, but also guide their migration in this process. Recent evidence indicates that neural progenitors also play a critical role in the development of the brain vascular network. At an early stage, neural progenitors have been found to facilitate the ingression of blood vessels from outside the neural tube, through VEGF and canonical Wnt signaling. Subsequently, neural progenitors directly communicate with endothelial cells to stabilize nascent brain vessels, in part through down-regulating Wnt pathway activity. Furthermore, neural progenitors promote nascent brain vessel integrity, through integrin αvβ8-dependent TGFβ signaling. In this review, we will discuss the evidence for, as well as questions that remain, regarding these novel roles of neural progenitors and the underlying mechanisms in their regulation of the nascent brain vascular network.

  1. Ruta graveolens L. induces death of glioblastoma cells and neural progenitors, but not of neurons, via ERK 1/2 and AKT activation.

    Science.gov (United States)

    Gentile, Maria Teresa; Ciniglia, Claudia; Reccia, Mafalda G; Volpicelli, Floriana; Gatti, Monica; Thellung, Stefano; Florio, Tullio; Melone, Mariarosa A B; Colucci-D'Amato, Luca

    2015-01-01

    Glioblastoma multiforme is a highly aggressive brain tumor whose prognosis is very poor. Due to early invasion of brain parenchyma, its complete surgical removal is nearly impossible, and even after aggressive combined treatment (association of surgery and chemo- and radio-therapy) five-year survival is only about 10%. Natural products are sources of novel compounds endowed with therapeutic properties in many human diseases, including cancer. Here, we report that the water extract of Ruta graveolens L., commonly known as rue, induces death in different glioblastoma cell lines (U87MG, C6 and U138) widely used to test novel drugs in preclinical studies. Ruta graveolens' effect was mediated by ERK1/2 and AKT activation, and the inhibition of these pathways, via PD98058 and wortmannin, reverted its antiproliferative activity. Rue extract also affects survival of neural precursor cells (A1) obtained from embryonic mouse CNS. As in the case of glioma cells, rue stimulates the activation of ERK1/2 and AKT in A1 cells, whereas their blockade by pharmacological inhibitors prevents cell death. Interestingly, upon induction of differentiation and cell cycle exit, A1 cells become resistant to rue's noxious effects but not to those of temozolomide and cisplatin, two alkylating agents widely used in glioblastoma therapy. Finally, rutin, a major component of the Ruta graveolens water extract, failed to cause cell death, suggesting that rutin by itself is not responsible for the observed effects. In conclusion, we report that rue extracts induce glioma cell death, discriminating between proliferating/undifferentiated and non-proliferating/differentiated neurons. Thus, it can be a promising tool to isolate novel drugs and also to discover targets for therapeutic intervention.

  2. Ruta graveolens L. induces death of glioblastoma cells and neural progenitors, but not of neurons, via ERK 1/2 and AKT activation.

    Directory of Open Access Journals (Sweden)

    Maria Teresa Gentile

    Full Text Available Glioblastoma multiforme is a highly aggressive brain tumor whose prognosis is very poor. Due to early invasion of brain parenchyma, its complete surgical removal is nearly impossible, and even after aggressive combined treatment (association of surgery and chemo- and radio-therapy five-year survival is only about 10%. Natural products are sources of novel compounds endowed with therapeutic properties in many human diseases, including cancer. Here, we report that the water extract of Ruta graveolens L., commonly known as rue, induces death in different glioblastoma cell lines (U87MG, C6 and U138 widely used to test novel drugs in preclinical studies. Ruta graveolens' effect was mediated by ERK1/2 and AKT activation, and the inhibition of these pathways, via PD98058 and wortmannin, reverted its antiproliferative activity. Rue extract also affects survival of neural precursor cells (A1 obtained from embryonic mouse CNS. As in the case of glioma cells, rue stimulates the activation of ERK1/2 and AKT in A1 cells, whereas their blockade by pharmacological inhibitors prevents cell death. Interestingly, upon induction of differentiation and cell cycle exit, A1 cells become resistant to rue's noxious effects but not to those of temozolomide and cisplatin, two alkylating agents widely used in glioblastoma therapy. Finally, rutin, a major component of the Ruta graveolens water extract, failed to cause cell death, suggesting that rutin by itself is not responsible for the observed effects. In conclusion, we report that rue extracts induce glioma cell death, discriminating between proliferating/undifferentiated and non-proliferating/differentiated neurons. Thus, it can be a promising tool to isolate novel drugs and also to discover targets for therapeutic intervention.

  3. Lgr5+ve Stem/Progenitor Cells Contribute to Nephron Formation during Kidney Development

    Directory of Open Access Journals (Sweden)

    Nick Barker

    2012-09-01

    Full Text Available Multipotent stem cells and their lineage-restricted progeny drive nephron formation within the developing kidney. Here, we document expression of the adult stem cell marker Lgr5 in the developing kidney and assess the stem/progenitor identity of Lgr5+ve cells via in vivo lineage tracing. The appearance and localization of Lgr5+ve cells coincided with that of the S-shaped body around embryonic day 14. Lgr5 expression remained restricted to cell clusters within developing nephrons in the cortex until postnatal day 7, when expression was permanently silenced. In vivo lineage tracing identified Lgr5 as a marker of a stem/progenitor population within nascent nephrons dedicated to generating the thick ascending limb of Henle’s loop and distal convoluted tubule. The Lgr5 surface marker and experimental models described here will be invaluable for deciphering the contribution of early nephron stem cells to developmental defects and for isolating human nephron progenitors as a prerequisite to evaluating their therapeutic potential.

  4. Wnt2 Regulates Progenitor Proliferation in the Developing Ventral Midbrain*

    Science.gov (United States)

    Sousa, Kyle M.; Villaescusa, J. Carlos; Cajanek, Lukas; Ondr, Jennifer K.; Castelo-Branco, Goncalo; Hofstra, Wytske; Bryja, Vitezslav; Palmberg, Carina; Bergman, Tomas; Wainwright, Brandon; Lang, Richard A.; Arenas, Ernest

    2010-01-01

    Wnts are secreted, lipidated proteins that regulate multiple aspects of brain development, including dopaminergic neuron development. In this study, we perform the first purification and signaling analysis of Wnt2 and define the function of Wnt2 in ventral midbrain precursor cultures, as well as in Wnt2-null mice in vivo. We found that purified Wnt2 induces the phosphorylation of both Lrp5/6 and Dvl-2/3, and activates β-catenin in SN4741 dopaminergic cells. Moreover, purified Wnt2 increases progenitor proliferation, and the number of dopaminergic neurons in ventral midbrain precursor cultures. In agreement with these findings, analysis of the ventral midbrain of developing Wnt2-null mice revealed a decrease in progenitor proliferation and neurogenesis that lead to a decrease in the number of postmitotic precursors and dopaminergic neurons. Collectively, our observations identify Wnt2 as a novel regulator of dopaminergic progenitors and dopaminergic neuron development. PMID:20018874

  5. Wnt2 regulates progenitor proliferation in the developing ventral midbrain.

    Science.gov (United States)

    Sousa, Kyle M; Villaescusa, J Carlos; Cajanek, Lukas; Ondr, Jennifer K; Castelo-Branco, Goncalo; Hofstra, Wytske; Bryja, Vitezslav; Palmberg, Carina; Bergman, Tomas; Wainwright, Brandon; Lang, Richard A; Arenas, Ernest

    2010-03-05

    Wnts are secreted, lipidated proteins that regulate multiple aspects of brain development, including dopaminergic neuron development. In this study, we perform the first purification and signaling analysis of Wnt2 and define the function of Wnt2 in ventral midbrain precursor cultures, as well as in Wnt2-null mice in vivo. We found that purified Wnt2 induces the phosphorylation of both Lrp5/6 and Dvl-2/3, and activates beta-catenin in SN4741 dopaminergic cells. Moreover, purified Wnt2 increases progenitor proliferation, and the number of dopaminergic neurons in ventral midbrain precursor cultures. In agreement with these findings, analysis of the ventral midbrain of developing Wnt2-null mice revealed a decrease in progenitor proliferation and neurogenesis that lead to a decrease in the number of postmitotic precursors and dopaminergic neurons. Collectively, our observations identify Wnt2 as a novel regulator of dopaminergic progenitors and dopaminergic neuron development.

  6. GSK-3 is a master regulator of neural progenitor homeostasis

    Science.gov (United States)

    Kim, Woo-Yang; Wang, Xinshuo; Wu, Yaohong; Doble, Bradley W; Patel, Satish; Woodgett, James R; Snider, William D

    2016-01-01

    The development of the brain requires the exquisite coordination of progenitor proliferation and differentiation to achieve complex circuit assembly. It has been suggested that glycogen synthase kinase 3 (GSK-3) acts as an integrating molecule for multiple proliferation and differentiation signals because of its essential role in the RTK, Wnt and Shh signaling pathways. We created conditional mutations that deleted both the α and β forms of GSK-3 in mouse neural progenitors. GSK-3 deletion resulted in massive hyperproliferation of neural progenitors along the entire neuraxis. Generation of both intermediate neural progenitors and postmitotic neurons was markedly suppressed. These effects were associated with the dysregulation of β-catenin, Sonic Hedgehog, Notch and fibroblast growth factor signaling. Our results indicate that GSK-3 signaling is an essential mediator of homeostatic controls that regulate neural progenitors during mammalian brain development. PMID:19801986

  7. Fate mapping by piggyBac transposase reveals that neocortical GLAST+ progenitors generate more astrocytes than Nestin+ progenitors in rat neocortex.

    Science.gov (United States)

    Siddiqi, Faez; Chen, Fuyi; Aron, Abraham W; Fiondella, Christopher G; Patel, Komal; LoTurco, Joseph J

    2014-02-01

    Progenitors within the neocortical ventricular zone (VZ) first generate pyramidal neurons and then astrocytes. We applied novel piggyBac transposase lineage tracking methods to fate-map progenitor populations positive for Nestin or glutamate and aspartate transpoter (GLAST) promoter activities in the rat neocortex. GLAST+ and Nestin+ progenitors at embryonic day 13 (E13) produce lineages containing similar rations of neurons and astrocytes. By E15, the GLAST+ progenitor population diverges significantly to produce lineages with 5-10-fold more astrocytes relative to neurons than generated by the Nestin+ population. To determine when birth-dated progeny within GLAST+ and Nestin+ populations diverge, we used a Cre/loxP fate-mapping system in which plasmids are lost after a cell division. By E18, birth-dated progeny of GLAST+ progenitors give rise to 2-3-fold more neocortical astrocytes than do Nestin+ progenitors. Finally, we used a multicolor clonal labeling method to show that the GLAST+ population labeled at E15 generates astrocyte progenitors that produce larger, spatially restricted, clonal clusters than the Nestin+ population. This study provides in vivo evidence that by mid-corticogenesis (E15), VZ progenitor populations have significantly diversified in terms of their potential to generate astrocytes and neurons.

  8. Light-induced Notch activity controls neurogenic and gliogenic potential of neural progenitors.

    Science.gov (United States)

    Kim, Kyung-Tai; Song, Mi-Ryoung

    2016-10-28

    Oscillations in Notch signaling are essential for reserving neural progenitors for cellular diversity in developing brains. Thus, steady and prolonged overactivation of Notch signaling is not suitable for generating neurons. To acquire greater temporal control of Notch activity and mimic endogenous oscillating signals, here we adopted a light-inducible transgene system to induce active form of Notch NICD in neural progenitors. Alternating Notch activity saved more progenitors that are prone to produce neurons creating larger number of mixed clones with neurons and progenitors in vitro, compared to groups with no light or continuous light stimulus. Furthermore, more upper layer neurons and astrocytes arose upon intermittent Notch activity, indicating that dynamic Notch activity maintains neural progeny and fine-tune neuron-glia diversity.

  9. GDE2 regulates subtype-specific motor neuron generation through inhibition of Notch signaling.

    Science.gov (United States)

    Sabharwal, Priyanka; Lee, Changhee; Park, Sungjin; Rao, Meenakshi; Sockanathan, Shanthini

    2011-09-22

    The specification of spinal interneuron and motor neuron identities initiates within progenitor cells, while motor neuron subtype diversification is regulated by hierarchical transcriptional programs implemented postmitotically. Here we find that mice lacking GDE2, a six-transmembrane protein that triggers motor neuron generation, exhibit selective losses of distinct motor neuron subtypes, specifically in defined subsets of limb-innervating motor pools that correlate with the loss of force-generating alpha motor neurons. Mechanistically, GDE2 is expressed by postmitotic motor neurons but utilizes extracellular glycerophosphodiester phosphodiesterase activity to induce motor neuron generation by inhibiting Notch signaling in neighboring motor neuron progenitors. Thus, neuronal GDE2 controls motor neuron subtype diversity through a non-cell-autonomous feedback mechanism that directly regulates progenitor cell differentiation, implying that subtype specification initiates within motor neuron progenitor populations prior to their differentiation into postmitotic motor neurons.

  10. Neural progenitors, neurogenesis and the evolution of the neocortex.

    Science.gov (United States)

    Florio, Marta; Huttner, Wieland B

    2014-06-01

    The neocortex is the seat of higher cognitive functions and, in evolutionary terms, is the youngest part of the mammalian brain. Since its origin, the neocortex has expanded in several mammalian lineages, and this is particularly notable in humans. This expansion reflects an increase in the number of neocortical neurons, which is determined during development and primarily reflects the number of neurogenic divisions of distinct classes of neural progenitor cells. Consequently, the evolutionary expansion of the neocortex and the concomitant increase in the numbers of neurons produced during development entail interspecies differences in neural progenitor biology. Here, we review the diversity of neocortical neural progenitors, their interspecies variations and their roles in determining the evolutionary increase in neuron numbers and neocortex size.

  11. Molecular dissection of prethymic progenitor entry into the T lymphocyte developmental pathway

    Energy Technology Data Exchange (ETDEWEB)

    Fung, Elizabeth-sharon [Los Alamos National Laboratory

    2008-01-01

    Notch signaling activates T lineage differentiation from hemopoietic progenitors, but relatively few regulators that initiate this program have been identified, e.g., GATA3 and T cell factor-I (TCF-1) (gene name Tcli). To identify additional regulators of T cell specification, a cDNA libnlrY from mouse Pro-T cells was screened for genes that are specifically up-regulated in intrathymic T cell precursors as compared with myeloid progenitors. Over 90 genes of interest were identified, and 35 of 44 tested were confirmed to be more highly expressed in T lineage precursors relative to precursors of B and/or myeloid lineage. To a remarkable extent, however, expression of these T lineage-enriched genes, including zinc finger transcription factor, helicase, and signaling adaptor genes, was also shared by stem cells (Lin{sup -}Sca-1{sup +}Kit{sup +}CD27{sup -}) and multipotent progenitors (Lin{sup -}Sca-l{sup +}Kit{sup +}CD27{sup +}), although down-regulated in other lineages. Thus, a major fraction of these early T lineage genes are a regulatory legacy from stem cells. The few genes sharply up-regulated between multipotent progenitors and Pro-T cell stages included those encoding transcription factors Bclllb, TCF-I (Tcli), and HEBalt, Notch target Deltexl, Deltex3L, Fkbp5, Eval, and Tmem13l. Like GATA3 and Deltexl, Bclllb, Fkbp5, and Eval were dependent on Notch/Delta signaling for induction in fetal liver precursors, but only BcIlI band HEBalt were up-regulated between the first two stages of intrathymic T cell development (double negative I and double negative 2) corresponding to T lineage specification. Bclllb was uniquely T lineage restricted and induced by NotchlDelta signaling specifically upon entry into the T lineage differentiation pathway.

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

    Directory of Open Access Journals (Sweden)

    Yu-Qing Li

    2016-06-01

    Full Text Available 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.

  13. PROPERTIES OF PROLIFERATION AND DIFFERENTIATION OF NEONATAL RAT RETINAL PROGENITOR CELLS IN VITRO

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Neural stem or progenitor cells are i mmature,multipotent cells that have the capacityto differenti-ate into the three CNSlineages(neurons,astrocytesand oligodendrocytes)[1].Neuronal degeneration isthe cause of visual i mpair ment associated with prev-alent ocular diseases such as retinitis pigmentosa,age-related macular degeneration,retinal detach-ment and glaucoma[2].Transplantation of culturedneural stemcells/progenitors may helprestore visionby repopulating the damaged retina and replacingthe degenerati...

  14. Influence of endogenous ciliary neurotrophic factor on neural differentiation of adult rat hippocampal progenitors

    Institute of Scientific and Technical Information of China (English)

    Jun Ding; Zhili He; Juan Ruan; Ying Liu; Chengxin Gong; Shenggang Sun; Honghui Chen

    2013-01-01

    Ciliary neurotrophic factor is the only known neurotrophic factor that can promote differentiation of hippocampal neural progenitor cells to glial cells and neurons in adult rats. This process is similar to spontaneous differentiation. Therefore, ciliary neurotrophic factor may be involved in spontaneous differentiation of neural stem cells. To verify this hypothesis, the present study isolated neural progenitor cells from adult male rats and cultured them in vitro. Results showed that when neural progenitor cells were cultured in the absence of mitogen fibroblast growth factor-2 or epidermal growth factor, they underwent spontaneous differentiation into neurons and glial cells. Western blot and immunocytochemical staining showed that exogenous ciliary neurotrophic factor strongly induced adult hippocampal progenitor cells to differentiate into neurons and glial cells. Moreover, passage 4 adult hippocampal progenitor cells expressed high levels of endogenous ciliary neurotrophic factor, and a neutralizing antibody against ciliary neurotrophic factor prevented the spontaneous neuronal and glial differentiation of adult hippocampal progenitor cells. These results suggest that the spontaneous differentiation of adult hippocampal progenitor cells is mediated partially by endogenous ciliary neurotrophic factor.

  15. Shaping our minds: stem and progenitor cell diversity in the mammalian neocortex.

    Science.gov (United States)

    Franco, Santos J; Müller, Ulrich

    2013-01-09

    The neural circuits of the mammalian neocortex are crucial for perception, complex thought, cognition, and consciousness. This circuitry is assembled from many different neuronal subtypes with divergent properties and functions. Here, we review recent studies that have begun to clarify the mechanisms of cell-type specification in the neocortex, focusing on the lineage relationships between neocortical progenitors and subclasses of excitatory projection neurons. These studies reveal an unanticipated diversity in the progenitor pool that requires a revised view of prevailing models of cell-type specification in the neocortex. We propose a "sequential progenitor-diversification model" that integrates current knowledge to explain how projection neuron diversity is achieved by mechanisms acting on proliferating progenitors and their postmitotic offspring. We discuss the implications of this model for our understanding of brain evolution and pathological states of the neocortex.

  16. Slit/Robo signaling modulates the proliferation of central nervous system progenitors.

    Science.gov (United States)

    Borrell, Víctor; Cárdenas, Adrián; Ciceri, Gabriele; Galcerán, Joan; Flames, Nuria; Pla, Ramón; Nóbrega-Pereira, Sandrina; García-Frigola, Cristina; Peregrín, Sandra; Zhao, Zhen; Ma, Le; Tessier-Lavigne, Marc; Marín, Oscar

    2012-10-18

    Neurogenesis relies on a delicate balance between progenitor maintenance and neuronal production. Progenitors divide symmetrically to increase the pool of dividing cells. Subsequently, they divide asymmetrically to self-renew and produce new neurons or, in some brain regions, intermediate progenitor cells (IPCs). Here we report that central nervous system progenitors express Robo1 and Robo2, receptors for Slit proteins that regulate axon guidance, and that absence of these receptors or their ligands leads to loss of ventricular mitoses. Conversely, production of IPCs is enhanced in Robo1/2 and Slit1/2 mutants, suggesting that Slit/Robo signaling modulates the transition between primary and intermediate progenitors. Unexpectedly, these defects do not lead to transient overproduction of neurons, probably because supernumerary IPCs fail to detach from the ventricular lining and cycle very slowly. At the molecular level, the role of Slit/Robo in progenitor cells involves transcriptional activation of the Notch effector Hes1. These findings demonstrate that Robo signaling modulates progenitor cell dynamics in the developing brain.

  17. Fate-restricted neural progenitors in the mammalian cerebral cortex.

    Science.gov (United States)

    Franco, Santos J; Gil-Sanz, Cristina; Martinez-Garay, Isabel; Espinosa, Ana; Harkins-Perry, Sarah R; Ramos, Cynthia; Müller, Ulrich

    2012-08-10

    During development of the mammalian cerebral cortex, radial glial cells (RGCs) generate layer-specific subtypes of excitatory neurons in a defined temporal sequence, in which lower-layer neurons are formed before upper-layer neurons. It has been proposed that neuronal subtype fate is determined by birthdate through progressive restriction of the neurogenic potential of a common RGC progenitor. Here, we demonstrate that the murine cerebral cortex contains RGC sublineages with distinct fate potentials. Using in vivo genetic fate mapping and in vitro clonal analysis, we identified an RGC lineage that is intrinsically specified to generate only upper-layer neurons, independently of niche and birthdate. Because upper cortical layers were expanded during primate evolution, amplification of this RGC pool may have facilitated human brain evolution.

  18. Multiple Modes of Communication between Neurons and Oligodendrocyte Precursor Cells

    NARCIS (Netherlands)

    Maldonado, Paloma P; Angulo, María Cecilia

    2015-01-01

    The surprising discovery of bona fide synapses between neurons and oligodendrocytes precursor cells (OPCs) 15 years ago placed these progenitors as real partners of neurons in the CNS. The role of these synapses has not been established yet, but a main hypothesis is that neuron-OPC synaptic activity

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

    Directory of Open Access Journals (Sweden)

    Seong-Ho Koh

    Full Text Available 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.

  20. Characterization of Proliferating Neural Progenitors after Spinal Cord Injury in Adult Zebrafish.

    Directory of Open Access Journals (Sweden)

    Subhra Prakash Hui

    Full Text Available Zebrafish can repair their injured brain and spinal cord after injury unlike adult mammalian central nervous system. Any injury to zebrafish spinal cord would lead to increased proliferation and neurogenesis. There are presences of proliferating progenitors from which both neuronal and glial loss can be reversed by appropriately generating new neurons and glia. We have demonstrated the presence of multiple progenitors, which are different types of proliferating populations like Sox2+ neural progenitor, A2B5+ astrocyte/ glial progenitor, NG2+ oligodendrocyte progenitor, radial glia and Schwann cell like progenitor. We analyzed the expression levels of two common markers of dedifferentiation like msx-b and vimentin during regeneration along with some of the pluripotency associated factors to explore the possible role of these two processes. Among the several key factors related to pluripotency, pou5f1 and sox2 are upregulated during regeneration and associated with activation of neural progenitor cells. Uncovering the molecular mechanism for endogenous regeneration of adult zebrafish spinal cord would give us more clues on important targets for future therapeutic approach in mammalian spinal cord repair and regeneration.

  1. Distribution and characterization of progenitor cells within the human filum terminale.

    Directory of Open Access Journals (Sweden)

    Lisa Arvidsson

    Full Text Available BACKGROUND: Filum terminale (FT is a structure that is intimately associated with conus medullaris, the most caudal part of the spinal cord. It is well documented that certain regions of the adult human central nervous system contains undifferentiated, progenitor cells or multipotent precursors. The primary objective of this study was to describe the distribution and progenitor features of this cell population in humans, and to confirm their ability to differentiate within the neuroectodermal lineage. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrate that neural stem/progenitor cells are present in FT obtained from patients treated for tethered cord. When human or rat FT-derived cells were cultured in defined medium, they proliferated and formed neurospheres in 13 out of 21 individuals. Cells expressing Sox2 and Musashi-1 were found to outline the central canal, and also to be distributed in islets throughout the whole FT. Following plating, the cells developed antigen profiles characteristic of astrocytes (GFAP and neurons (β-III-tubulin. Addition of PDGF-BB directed the cells towards a neuronal fate. Moreover, the cells obtained from young donors shows higher capacity for proliferation and are easier to expand than cells derived from older donors. CONCLUSION/SIGNIFICANCE: The identification of bona fide neural progenitor cells in FT suggests a possible role for progenitor cells in this extension of conus medullaris and may provide an additional source of such cells for possible therapeutic purposes. Filum terminale, human, progenitor cells, neuron, astrocytes, spinal cord.

  2. S-phase duration is the main target of cell cycle regulation in neural progenitors of developing ferret neocortex.

    Science.gov (United States)

    Turrero García, Miguel; Chang, YoonJeung; Arai, Yoko; Huttner, Wieland B

    2016-02-15

    The evolutionary expansion of the neocortex primarily reflects increases in abundance and proliferative capacity of cortical progenitors and in the length of the neurogenic period during development. Cell cycle parameters of neocortical progenitors are an important determinant of cortical development. The ferret (Mustela putorius furo), a gyrencephalic mammal, has gained increasing importance as a model for studying corticogenesis. Here, we have studied the abundance, proliferation, and cell cycle parameters of different neural progenitor types, defined by their differential expression of the transcription factors Pax6 and Tbr2, in the various germinal zones of developing ferret neocortex. We focused our analyses on postnatal day 1, a late stage of cortical neurogenesis when upper-layer neurons are produced. Based on cumulative 5-ethynyl-2'-deoxyuridine (EdU) labeling as well as Ki67 and proliferating cell nuclear antigen (PCNA) immunofluorescence, we determined the duration of the various cell cycle phases of the different neocortical progenitor subpopulations. Ferret neocortical progenitors were found to exhibit longer cell cycles than those of rodents and little variation in the duration of G1 among distinct progenitor types, also in contrast to rodents. Remarkably, the main difference in cell cycle parameters among the various progenitor types was the duration of S-phase, which became shorter as progenitors progressively changed transcription factor expression from patterns characteristic of self-renewal to those of neuron production. Hence, S-phase duration emerges as major target of cell cycle regulation in cortical progenitors of this gyrencephalic mammal.

  3. From progenitor to afterlife

    CERN Document Server

    Chevalier, R A

    2006-01-01

    The sequence of massive star supernova types IIP (plateau light curve), IIL (linear light curve), IIb, IIn (narrow line), Ib, and Ic roughly represents a sequence of increasing mass loss during the stellar evolution. The mass loss affects the velocity distribution of the ejecta composition; in particular, only the IIP's typically end up with H moving at low velocity. Radio and X-ray observations of extragalactic supernovae show varying mass loss properties that are in line with expectations for the progenitor stars. For young supernova remnants, pulsar wind nebulae and circumstellar interaction provide probes of the inner ejecta and higher velocity ejecta, respectively. Among the young remnants, there is evidence for supernovae over a range of types, including those that exploded with much of the H envelope present (Crab Nebula, 3C 58, 0540--69) and those that exploded after having lost most of their H envelope (Cas A, G292.0+1.8).

  4. Single-Cell Transcript Profiles Reveal Multilineage Priming in Early Progenitors Derived from Lgr5+ Intestinal Stem Cells

    Directory of Open Access Journals (Sweden)

    Tae-Hee Kim

    2016-08-01

    Full Text Available Lgr5+ intestinal stem cells (ISCs drive epithelial self-renewal, and their immediate progeny—intestinal bipotential progenitors—produce absorptive and secretory lineages via lateral inhibition. To define features of early transit from the ISC compartment, we used a microfluidics approach to measure selected stem- and lineage-specific transcripts in single Lgr5+ cells. We identified two distinct cell populations, one that expresses known ISC markers and a second, abundant population that simultaneously expresses markers of stem and mature absorptive and secretory cells. Single-molecule mRNA in situ hybridization and immunofluorescence verified expression of lineage-restricted genes in a subset of Lgr5+ cells in vivo. Transcriptional network analysis revealed that one group of Lgr5+ cells arises from the other and displays characteristics expected of bipotential progenitors, including activation of Notch ligand and cell-cycle-inhibitor genes. These findings define the earliest steps in ISC differentiation and reveal multilineage gene priming as a fundamental property of the process.

  5. Progenitors of type Ia supernovae

    CERN Document Server

    Maeda, Keiichi

    2016-01-01

    Natures of progenitors of type Ia Supernovae (SNe Ia) have not yet been clarified. There has been long and intensive discussion on whether the so-called single degenerate (SD) scenario or the double degenerate (DD) scenario, or anything else, could explain a major population of SNe Ia, but the conclusion has not yet been reached. With rapidly increasing observational data and new theoretical ideas, the field of studying the SN Ia progenitors has been quickly developing, and various new insights have been obtained in recent years. This article aims at providing a summary of the current situation regarding the SN Ia progenitors, both in theory and observations. It seems difficult to explain the emerging diversity seen in observations of SNe Ia by a single population, and we emphasize that it is important to clarify links between different progenitor scenarios and different sub-classes of SNe Ia.

  6. 间充质祖细胞源性的神经元样细胞肌内移植后自身特性的维持%Characteristic maintenance of mesenchymal progenitor cells-derived neuron-like cells after being transplanted into muscle

    Institute of Scientific and Technical Information of China (English)

    赵文勇; 万立华; 粟永萍; 冉新泽

    2013-01-01

    目的 探讨间充质祖细胞(mesenchymal progenitor cells,MPCs)源性的神经元样细胞肌内移植后能否维持其自身特性.方法 取3周龄健康GFP转基因C57小鼠后肢长骨进行MPC培养及鉴定,选取生长良好的第3代MPC,采用神经元原代培养上清液进行神经元样细胞诱导分化后收集细胞,并制备成5×105/μL细胞悬液备用.选取12周龄健康C57小鼠24只,按随机数字表法分为损伤+移植细胞组、损伤+生理盐水组、假手术+移植细胞组、假手术+生理盐水组.损伤+移植细胞组及假手术+移植细胞组:将制备的5 μL MPC悬液散点注入小鼠三头肌内;损伤+生理盐水组和假手术+生理盐水组:同法注入等量生理盐水.术后4周取材,荧光显微镜下观察肌内移植细胞存活情况,电镜观察肌肉超微结构的变化,免疫荧光染色检测神经元特异性标志物NSE、NeuN及神经胶质特异性标志物GFAP的表达情况.结果 肌内移植细胞生长良好且均匀分布于肌细胞间隙,并抑制了肌细胞核、线粒体、内质网的退变及肌肉纤维化的发生.损伤+移植细胞组定植存活的移植细胞阳性表达:NSE(58.35±1.37)%、NeuN(60.22 ±0.16)%及GFAP(13.32±1.65)%,损伤+生理盐水组、假手术+移植细胞组、假手术+生理盐水组均无阳性细胞表达.结论 MPC具有良好的生物学活性,经体外诱导分化为神经元及神经胶质样细胞后移植于失神经支配肌内可定植存活,并能够维持神经元及神经胶质样细胞的特性,同时有效抑制了肌细胞核、线粒体、内质网的退变及肌肉纤维化的发生.%Objective To study the characteristic maintenance of mesenchymal progenitor cells (MPCs)-derived neuron-like cells after being transplanted into denervated muscle. Methods MPCs were separated from bones of hind limbs of GFP transgenic C57 mice mechanically, and were cultured and induced to differentiate in vitro. After being induced directionally

  7. Retinoid signaling in control of progenitor cell differentiation during mouse development.

    Science.gov (United States)

    Duester, Gregg

    2013-12-01

    The vitamin A metabolite retinoic acid (RA) serves as a ligand for nuclear RA receptors that control differentiation of progenitor cells important for vertebrate development. Genetic studies in mouse embryos deficient for RA-generating enzymes have been invaluable for deciphering RA function. RA first begins to act during early organogenesis when RA generated in trunk mesoderm begins to function as a diffusible signal controlling progenitor cell differentiation. In neuroectoderm, RA functions as an instructive signal to stimulate neuronal differentiation of progenitor cells in the hindbrain and spinal cord. RA is not required for early neuronal differentiation of the forebrain, but at later stages RA stimulates neuronal differentiation in forebrain basal ganglia. RA also acts as a permissive signal for differentiation by repressing fibroblast growth factor (FGF) signaling in differentiated cells as they emerge from progenitor populations in the caudal progenitor zone and second heart field. In addition, RA signaling stimulates differentiation of spermatogonial germ cells and induces meiosis in male but not female gonads. A more complete understanding of the normal functions of RA signaling during development will guide efforts to use RA as a differentiation agent for therapeutic purposes.

  8. Mesenchymal progenitor cells for the osteogenic lineage.

    Science.gov (United States)

    Ono, Noriaki; Kronenberg, Henry M

    2015-09-01

    Mesenchymal progenitors of the osteogenic lineage provide the flexibility for bone to grow, maintain its function and homeostasis. Traditionally, colony-forming-unit fibroblasts (CFU-Fs) have been regarded as surrogates for mesenchymal progenitors; however, this definition cannot address the function of these progenitors in their native setting. Transgenic murine models including lineage-tracing technologies based on the cre-lox system have proven to be useful in delineating mesenchymal progenitors in their native environment. Although heterogeneity of cell populations of interest marked by a promoter-based approach complicates overall interpretation, an emerging complexity of mesenchymal progenitors has been revealed. Current literatures suggest two distinct types of bone progenitor cells; growth-associated mesenchymal progenitors contribute to explosive growth of bone in early life, whereas bone marrow mesenchymal progenitors contribute to the much slower remodeling process and response to injury that occurs mainly in adulthood. More detailed relationships of these progenitors need to be studied through further experimentation.

  9. Neural stem/progenitor cells in Alzheimer's disease.

    Science.gov (United States)

    Tincer, Gizem; Mashkaryan, Violeta; Bhattarai, Prabesh; Kizil, Caghan

    2016-03-01

    Alzheimer's disease (AD) is the most prevalent neurodegenerative disease and a worldwide health challenge. Different therapeutic approaches are being developed to reverse or slow the loss of affected neurons. Another plausible therapeutic way that may complement the studies is to increase the survival of existing neurons by mobilizing the existing neural stem/progenitor cells (NSPCs) - i.e. "induce their plasticity" - to regenerate lost neurons despite the existing pathology and unfavorable environment. However, there is controversy about how NSPCs are affected by the unfavorable toxic environment during AD. In this review, we will discuss the use of stem cells in neurodegenerative diseases and in particular how NSPCs affect the AD pathology and how neurodegeneration affects NSPCs. In the end of this review, we will discuss how zebrafish as a useful model organism with extensive regenerative ability in the brain might help to address the molecular programs needed for NSPCs to respond to neurodegeneration by enhanced neurogenesis.

  10. Environmental Enrichment Increases Progenitor Cell Survival in the Dentate Gyrus following Lateral Fluid Percussion Injury

    OpenAIRE

    2005-01-01

    Neurons in the hilus of the dentate gyrus are lost following a lateral fluid percussion injury. Environmental enrichment is known to increase neurogenesis in the dentate in intact rats, suggesting that it might also do so following fluid percussion injury, and potentially provide replacements for lost neurons. We report that 1 hour of daily environmental enrichment for 3 weeks increased the number of progenitor cells in the dentate following fluid percussion injury, but only on the ipsilesion...

  11. Regulation of neural progenitor proliferation and survival by beta1 integrins

    DEFF Research Database (Denmark)

    Leone, Dino P; Relvas, João B; Campos, Lia S;

    2005-01-01

    Neural stem cells give rise to undifferentiated nestin-positive progenitors that undergo extensive cell division before differentiating into neuronal and glial cells. The precise control of this process is likely to be, at least in part, controlled by instructive cues originating from...... the extracellular environment. Some of these cues are interpreted by the integrin family of extracellular matrix receptors. Using neurosphere cell cultures as a model system, we show that beta1-integrin signalling plays a crucial role in the regulation of progenitor cell proliferation, survival and migration....... Following conditional genetic ablation of the beta1-integrin allele, and consequent loss of beta1-integrin cell surface protein, mutant nestin-positive progenitor cells proliferate less and die in higher numbers than their wild-type counterparts. Mutant progenitor cell migration on different ECM substrates...

  12. Erythropoietin and the effect of oxygen during proliferation and differentiation of human neural progenitor cells

    Directory of Open Access Journals (Sweden)

    Frech Moritz J

    2010-12-01

    Full Text Available Abstract Background Hypoxia plays a critical role in various cellular mechanisms, including proliferation and differentiation of neural stem and progenitor cells. In the present study, we explored the impact of lowered oxygen on the differentiation potential of human neural progenitor cells, and the role of erythropoietin in the differentiation process. Results In this study we demonstrate that differentiation of human fetal neural progenitor cells under hypoxic conditions results in an increased neurogenesis. In addition, expansion and proliferation under lowered oxygen conditions also increased neuronal differentiation, although proliferation rates were not altered compared to normoxic conditions. Erythropoietin partially mimicked these hypoxic effects, as shown by an increase of the metabolic activity during differentiation and protection of differentiated cells from apoptosis. Conclusion These results provide evidence that hypoxia promotes the differentiation of human fetal neural progenitor cells, and identifies the involvement of erythropoietin during differentiation as well as different cellular mechanisms underlying the induction of differentiation mediated by lowered oxygen levels.

  13. Amplification of neural stem cell proliferation by intermediate progenitor cells in Drosophila brain development

    Directory of Open Access Journals (Sweden)

    Bello Bruno C

    2008-02-01

    Full Text Available Abstract Background In the mammalian brain, neural stem cells divide asymmetrically and often amplify the number of progeny they generate via symmetrically dividing intermediate progenitors. Here we investigate whether specific neural stem cell-like neuroblasts in the brain of Drosophila might also amplify neuronal proliferation by generating symmetrically dividing intermediate progenitors. Results Cell lineage-tracing and genetic marker analysis show that remarkably large neuroblast lineages exist in the dorsomedial larval brain of Drosophila. These lineages are generated by brain neuroblasts that divide asymmetrically to self renew but, unlike other brain neuroblasts, do not segregate the differentiating cell fate determinant Prospero to their smaller daughter cells. These daughter cells continue to express neuroblast-specific molecular markers and divide repeatedly to produce neural progeny, demonstrating that they are proliferating intermediate progenitors. The proliferative divisions of these intermediate progenitors have novel cellular and molecular features; they are morphologically symmetrical, but molecularly asymmetrical in that key differentiating cell fate determinants are segregated into only one of the two daughter cells. Conclusion Our findings provide cellular and molecular evidence for a new mode of neurogenesis in the larval brain of Drosophila that involves the amplification of neuroblast proliferation through intermediate progenitors. This type of neurogenesis bears remarkable similarities to neurogenesis in the mammalian brain, where neural stem cells as primary progenitors amplify the number of progeny they generate through generation of secondary progenitors. This suggests that key aspects of neural stem cell biology might be conserved in brain development of insects and mammals.

  14. Ischemia-induced neural stem/progenitor cells express pyramidal cell markers

    NARCIS (Netherlands)

    Clausen, Martijn; Nakagomi, Takayuki; Nakano-Doi, Akiko; Saino, Orie; Takata, Masashi; Taguchi, Akihiko; Luiten, Paul; Matsuyama, Tomohiro

    2011-01-01

    Adult brain-derived neural stem cells have acquired a lot of interest as an endurable neuronal cell source that can be used for central nervous system repair in a wide range of neurological disorders such as ischemic stroke. Recently, we identified injury-induced neural stem/progenitor cells in the

  15. Interneurons and oligodendrocyte progenitors form a structured synaptic network in the developing neocortex

    NARCIS (Netherlands)

    Orduz, David; Maldonado, Paloma P; Balia, Maddalena; Vélez-Fort, Mateo; de Sars, Vincent; Yanagawa, Yuchio; Emiliani, Valentina; Angulo, Maria Cecilia

    2015-01-01

    NG2 cells, oligodendrocyte progenitors, receive a major synaptic input from interneurons in the developing neocortex. It is presumed that these precursors integrate cortical networks where they act as sensors of neuronal activity. We show that NG2 cells of the developing somatosensory cortex form a

  16. Characterization of calcium responses and electrical activity in differentiating mouse neural progenitor cells in vitro

    NARCIS (Netherlands)

    de Groot, Martje W G D M; Dingemans, Milou M L; Rus, Katinka H; de Groot, Aart; Westerink, Remco H S

    2014-01-01

    In vitro methods for developmental neurotoxicity (DNT) testing have the potential to reduce animal use and increase insight into cellular and molecular mechanisms underlying chemical-induced alterations in the development of functional neuronal networks. Mouse neural progenitor cells (mNPCs) differe

  17. MyT1 Counteracts the Neural Progenitor Program to Promote Vertebrate Neurogenesis

    Directory of Open Access Journals (Sweden)

    Francisca F. Vasconcelos

    2016-10-01

    Full Text Available The generation of neurons from neural stem cells requires large-scale changes in gene expression that are controlled to a large extent by proneural transcription factors, such as Ascl1. While recent studies have characterized the differentiation genes activated by proneural factors, less is known on the mechanisms that suppress progenitor cell identity. Here, we show that Ascl1 induces the transcription factor MyT1 while promoting neuronal differentiation. We combined functional studies of MyT1 during neurogenesis with the characterization of its transcriptional program. MyT1 binding is associated with repression of gene transcription in neural progenitor cells. It promotes neuronal differentiation by counteracting the inhibitory activity of Notch signaling at multiple levels, targeting the Notch1 receptor and many of its downstream targets. These include regulators of the neural progenitor program, such as Hes1, Sox2, Id3, and Olig1. Thus, Ascl1 suppresses Notch signaling cell-autonomously via MyT1, coupling neuronal differentiation with repression of the progenitor fate.

  18. Interactions of primary neuroepithelial progenitor and brain endothelial cells: distinct effect on neural progenitor maintenance and differentiation by soluble factors and direct contact

    Institute of Scientific and Technical Information of China (English)

    Miguel A Gama Sosa; Rita De Gasperi; Anne B Rocher; Gissel M Perez; Keila Simons; Daniel E Cruz; Patrick R Hof; Gregory A Elder

    2007-01-01

    Neurovascular interactions are crucial for the normal development of the central nervous system. To study such interactions in primary cultures, we developed a procedure to simultaneously isolate neural progenitor and endothelial cell fractions from embryonic mouse brains. Depending on the culture conditions endothelial cells were found to favor maintenance of the neuroprogenitor phenotype through the production of soluble factors, or to promote neuronal differentiation of neural progenitors through direct contact. These apparently opposing effects could reflect differential cellular interactions needed for the proper development of the brain.

  19. Embryonic Heart Progenitors and Cardiogenesis

    Science.gov (United States)

    Brade, Thomas; Pane, Luna S.; Moretti, Alessandra; Chien, Kenneth R.; Laugwitz, Karl-Ludwig

    2013-01-01

    The mammalian heart is a highly specialized organ, comprised of many different cell types arising from distinct embryonic progenitor populations during cardiogenesis. Three precursor populations have been identified to contribute to different myocytic and nonmyocytic cell lineages of the heart: cardiogenic mesoderm cells (CMC), the proepicardium (PE), and cardiac neural crest cells (CNCCs). This review will focus on molecular cues necessary for proper induction, expansion, and lineage-specific differentiation of these progenitor populations during cardiac development in vivo. Moreover, we will briefly discuss how the knowledge gained on embryonic heart progenitor biology can be used to develop novel therapeutic strategies for the management of congenital heart disease as well as for improvement of cardiac function in ischemic heart disease. PMID:24086063

  20. Characterization of progenitor domains in the developing mouse thalamus.

    Science.gov (United States)

    Vue, Tou Yia; Aaker, Joshua; Taniguchi, Aya; Kazemzadeh, Christina; Skidmore, Jennifer M; Martin, Donna M; Martin, James F; Treier, Mathias; Nakagawa, Yasushi

    2007-11-01

    To understand the molecular basis of the specification of thalamic nuclei, we analyzed the expression patterns of various transcription factors and defined progenitor cell populations in the embryonic mouse thalamus. We show that the basic helix-loop-helix (bHLH) transcription factor Olig3 is expressed in the entire thalamic ventricular zone and the zona limitans intrathalamica (ZLI). Next, we define two distinct progenitor domains within the thalamus, which we name pTH-R and pTH-C, located caudal to the ZLI. pTH-R is immediately caudal to the ZLI and expresses Nkx2.2, Mash1, and Olig3. pTH-C is caudal to pTH-R and expresses Ngn1, Ngn2, and Olig3. Short-term lineage analysis of Olig3-, Mash1-, Ngn1-, and Ngn2-expressing progenitor cells as well as tracing the Pitx2 cell lineage suggests that pTH-C is the only major source of thalamic nuclei containing neurons that project to the cerebral cortex, whereas pTH-R and ZLI are likely to produce distinct postmitotic populations outside of the cortex-projecting part of the thalamus. To determine if pTH-C is composed of subdomains, we characterized expression of the homeodomain protein Dbx1 and the bHLH protein Olig2. We show that Dbx1 is expressed in caudodorsal-high to rostroventral-low gradient within pTH-C. Analysis of heterozygous Dbx1(nlslacZ) knockin mice demonstrated that Dbx1-expressing progenitors preferentially give rise to caudodorsal thalamic nuclei. Olig2 is expressed in an opposite gradient within pTH-C to that of Dbx1. These results establish the molecular heterogeneity within the progenitor cells of the thalamus, and suggest that such heterogeneity contributes to the specification of thalamic nuclei.

  1. Proneurotrophin-3 promotes cell cycle withdrawal of developing cerebellar granule cell progenitors via the p75 neurotrophin receptor.

    Science.gov (United States)

    Zanin, Juan Pablo; Abercrombie, Elizabeth; Friedman, Wilma J

    2016-07-19

    Cerebellar granule cell progenitors (GCP) proliferate extensively in the external granule layer (EGL) of the developing cerebellum prior to differentiating and migrating. Mechanisms that regulate the appropriate timing of cell cycle withdrawal of these neuronal progenitors during brain development are not well defined. The p75 neurotrophin receptor (p75(NTR)) is highly expressed in the proliferating GCPs, but is downregulated once the cells leave the cell cycle. This receptor has primarily been characterized as a death receptor for its ability to induce neuronal apoptosis following injury. Here we demonstrate a novel function for p75(NTR) in regulating proper cell cycle exit of neuronal progenitors in the developing rat and mouse EGL, which is stimulated by proNT3. In the absence of p75(NTR), GCPs continue to proliferate beyond their normal period, resulting in a larger cerebellum that persists into adulthood, with consequent motor deficits.

  2. Methylene blue promotes quiescence of rat neural progenitor cells.

    Science.gov (United States)

    Xie, Luokun; Choudhury, Gourav R; Wang, Jixian; Park, Yong; Liu, Ran; Yuan, Fang; Zhang, Chun-Li; Yorio, Thomas; Jin, Kunlin; Yang, Shao-Hua

    2014-01-01

    Neural stem cell-based treatment holds a new therapeutic opportunity for neurodegenerative disorders. Here, we investigated the effect of methylene blue on proliferation and differentiation of rat neural progenitor cells (NPCs) both in vitro and in vivo. We found that methylene blue inhibited proliferation and promoted quiescence of NPCs in vitro without affecting committed neuronal differentiation. Consistently, intracerebroventricular infusion of methylene blue significantly inhibited NPC proliferation at the subventricular zone (SVZ). Methylene blue inhibited mTOR signaling along with down-regulation of cyclins in NPCs in vitro and in vivo. In summary, our study indicates that methylene blue may delay NPC senescence through enhancing NPCs quiescence.

  3. Directed Differentiation of Human Embryonic Stem Cells into Neural Progenitors.

    Science.gov (United States)

    Banda, Erin; Grabel, Laura

    2016-01-01

    A variety of protocols have been used to produce neural progenitors from human embryonic stem cells. We have focused on a monolayer culture approach that generates neural rosettes. To initiate differentiation, cells are plated in a serum-free nutrient-poor medium in the presence of a BMP inhibitor. Depending on the cell line used, additional growth factor inhibitors may be required to promote neural differentiation. Long-term culture and addition of the Notch inhibitor DAPT can promote terminal neuronal differentiation. Extent of differentiation is monitored using immunocytochemistry for cell type-specific markers.

  4. Cortical ventricular zone progenitors and their progeny maintain spatial relationships and radial patterning during preplate development indicating an early protomap.

    Science.gov (United States)

    O'Leary, Dennis D M; Borngasser, Douglass

    2006-07-01

    The graded expression of transcription factors by progenitors in the ventricular zone (VZ) confers positional or area identity that is inherited by subplate (SP) neurons and governs their expression of guidance molecules for thalamocortical axons and other properties required for cortical area specification. This mechanism would be most efficient if VZ progenitors and their SP neuronal progeny maintain neighbor relationships during the generation of the preplate (PP), the precursor of the SP. Therefore, a major goal of this study is to determine whether progenitors in the cortical VZ and their progeny maintain neighbor relationships during the genesis of the neocortical PP. We used time-lapse video microscopy to follow the movements of VZ progenitors and the radial movement of their progeny and distribution in the PP in whole-mount or slice cortical explants from embryonic rats at stages when PP neurons are generated. We show that labeled VZ cells proliferate and have a strong tendency to retain neighbor relationships within the VZ and that their neuronal progeny move superficially along a radial column to form the overlying PP; during this process, their neuronal progeny also retain neighbor relationships and thereby form the PP in spatial register with the VZ progenitors that generate them. This behavior differs from that reported at later stages of cortical development, when cortical plate (CP) neurons are generated, and considerable dispersion is evident among both cells within the VZ and neuronal progeny as they migrate from the VZ to the CP. However, our findings show that at the early stage of cortical development, when PP/SP neurons are generated, the VZ is, at a cellular level, a "protomap" of the PP/SP.

  5. Disturbances in the positioning, proliferation and apoptosis of neural progenitors contribute to subcortical band heterotopia formation.

    Science.gov (United States)

    Fitzgerald, M P; Covio, M; Lee, K S

    2011-03-10

    Cortical malformations are commonly associated with intractable epilepsy and other developmental disorders. Our studies utilize the tish rat, a spontaneously occurring genetic model of subcortical band heterotopia (SBH) associated with epilepsy, to evaluate the developmental events underlying SBH formation in the neocortex. Our results demonstrate that Pax6(+) and Tbr2(+) progenitors are mislocalized in tish(+/-) and tish(-/-)- neocortex throughout neurogenesis. In addition, mislocalized tish(-/-) progenitors possess a longer cell cycle than wild type or normally-positioned tish(-/-) progenitors, owing to a lengthened G(2)+M+G(1) time. This mislocalization is not associated with adherens junction breakdown or loss of radial glial polarity in the ventricular zone (VZ), as assessed by immunohistochemistry against phalloidin (to identify F-actin), aPKC-λ and Par3. However, vimentin immunohistochemistry indicates that the radial glial scaffold is disrupted in the region of the tish(-/-) heterotopia. Moreover, lineage tracing experiments using in utero electroporation in tish(-/-) neocortex demonstrate that mislocalized progenitors do not retain contact with the ventricular surface and that ventricular/subventricular zone (SVZ) progenitors produce neurons that migrate into both the heterotopia and cortical plate (CP). Taken together, these findings define a series of developmental errors contributing to SBH formation that differs fundamentally from a primary error in neuronal migration.

  6. Transient, afferent input-dependent, postnatal niche for neural progenitor cells in the cochlear nucleus.

    Science.gov (United States)

    Volkenstein, Stefan; Oshima, Kazuo; Sinkkonen, Saku T; Corrales, C Eduardo; Most, Sam P; Chai, Renjie; Jan, Taha A; van Amerongen, Renée; Cheng, Alan G; Heller, Stefan

    2013-08-27

    In the cochlear nucleus (CN), the first central relay of the auditory pathway, the survival of neurons during the first weeks after birth depends on afferent innervation from the cochlea. Although input-dependent neuron survival has been extensively studied in the CN, neurogenesis has not been evaluated as a possible mechanism of postnatal plasticity. Here we show that new neurons are born in the CN during the critical period of postnatal plasticity. Coincidently, we found a population of neural progenitor cells that are controlled by a complex interplay of Wnt, Notch, and TGFβ/BMP signaling, in which low levels of TGFβ/BMP signaling are permissive for progenitor proliferation that is promoted by Wnt and Notch activation. We further show that cells with activated Wnt signaling reside in the CN and that these cells have high propensity for neurosphere formation. Cochlear ablation resulted in diminishment of progenitors and Wnt/β-catenin-active cells, suggesting that the neonatal CN maintains an afferent innervation-dependent population of progenitor cells that display active canonical Wnt signaling.

  7. Raman spectroscopy for discrimination of neural progenitor cells and their lineages (Conference Presentation)

    Science.gov (United States)

    Chen, Keren; Ong, William; Chew, Sing Yian; Liu, Quan

    2017-02-01

    Neurological diseases are one of the leading causes of adult disability and they are estimated to cause more deaths than cancer in the elderly population by 2040. Stem cell therapy has shown great potential in treating neurological diseases. However, before cell therapy can be widely adopted in the long term, a number of challenges need to be addressed, including the fundamental research about cellular development of neural progenitor cells. To facilitate the fundamental research of neural progenitor cells, many methods have been developed to identify neural progenitor cells. Although great progress has been made, there is still lack of an effective method to achieve fast, label-free and noninvasive differentiation of neural progenitor cells and their lineages. As a fast, label-free and noninvasive technique, spontaneous Raman spectroscopy has been conducted to characterize many types of stem cells including neural stem cells. However, to our best knowledge, it has not been studied for the discrimination of neural progenitor cells from specific lineages. Here we report the differentiation of neural progenitor cell from their lineages including astrocytes, oligodendrocytes and neurons using spontaneous Raman spectroscopy. Moreover, we also evaluate the influence of system parameters during spectral acquisition on the quality of measured Raman spectra and the accuracy of classification using the spectra, which yield a set of optimal system parameters facilitating future studies.

  8. Sonic hedgehog lineage in the mouse hypothalamus: from progenitor domains to hypothalamic regions

    Directory of Open Access Journals (Sweden)

    Alvarez-Bolado Gonzalo

    2012-01-01

    Full Text Available Abstract Background The hypothalamus is a brain region with essential functions for homeostasis and energy metabolism, and alterations of its development can contribute to pathological conditions in the adult, like hypertension, diabetes or obesity. However, due to the anatomical complexity of the hypothalamus, its development is not well understood. Sonic hedgehog (Shh is a key developmental regulator gene expressed in a dynamic pattern in hypothalamic progenitor cells. To obtain insight into hypothalamic organization, we used genetic inducible fate mapping (GIFM to map the lineages derived from Shh-expressing progenitor domains onto the four rostrocaudally arranged hypothalamic regions: preoptic, anterior, tuberal and mammillary. Results Shh-expressing progenitors labeled at an early stage (before embryonic day (E9.5 contribute neurons and astrocytes to a large caudal area including the mammillary and posterior tuberal regions as well as tanycytes (specialized median eminence glia. Progenitors labeled at later stages (after E9.5 give rise to neurons and astrocytes of the entire tuberal region and in particular the ventromedial nucleus, but not to cells in the mammillary region and median eminence. At this stage, an additional Shh-expressing domain appears in the preoptic area and contributes mostly astrocytes to the hypothalamus. Shh-expressing progenitors do not contribute to the anterior region at any stage. Finally, we show a gradual shift from neurogenesis to gliogenesis, so that progenitors expressing Shh after E12.5 generate almost exclusively hypothalamic astrocytes. Conclusions We define a fate map of the hypothalamus, based on the dynamic expression of Shh in the hypothalamic progenitor zones. We provide evidence that the large neurogenic Shh-expressing progenitor domains of the ventral diencephalon are continuous with those of the midbrain. We demonstrate that the four classical transverse zones of the hypothalamus have clearly

  9. Sonic hedgehog lineage in the mouse hypothalamus: from progenitor domains to hypothalamic regions

    Science.gov (United States)

    2012-01-01

    Background The hypothalamus is a brain region with essential functions for homeostasis and energy metabolism, and alterations of its development can contribute to pathological conditions in the adult, like hypertension, diabetes or obesity. However, due to the anatomical complexity of the hypothalamus, its development is not well understood. Sonic hedgehog (Shh) is a key developmental regulator gene expressed in a dynamic pattern in hypothalamic progenitor cells. To obtain insight into hypothalamic organization, we used genetic inducible fate mapping (GIFM) to map the lineages derived from Shh-expressing progenitor domains onto the four rostrocaudally arranged hypothalamic regions: preoptic, anterior, tuberal and mammillary. Results Shh-expressing progenitors labeled at an early stage (before embryonic day (E)9.5) contribute neurons and astrocytes to a large caudal area including the mammillary and posterior tuberal regions as well as tanycytes (specialized median eminence glia). Progenitors labeled at later stages (after E9.5) give rise to neurons and astrocytes of the entire tuberal region and in particular the ventromedial nucleus, but not to cells in the mammillary region and median eminence. At this stage, an additional Shh-expressing domain appears in the preoptic area and contributes mostly astrocytes to the hypothalamus. Shh-expressing progenitors do not contribute to the anterior region at any stage. Finally, we show a gradual shift from neurogenesis to gliogenesis, so that progenitors expressing Shh after E12.5 generate almost exclusively hypothalamic astrocytes. Conclusions We define a fate map of the hypothalamus, based on the dynamic expression of Shh in the hypothalamic progenitor zones. We provide evidence that the large neurogenic Shh-expressing progenitor domains of the ventral diencephalon are continuous with those of the midbrain. We demonstrate that the four classical transverse zones of the hypothalamus have clearly defined progenitor domains

  10. Harmine stimulates proliferation of human neural progenitors

    Science.gov (United States)

    Dakic, Vanja; Maciel, Renata de Moraes; Drummond, Hannah; Nascimento, Juliana M.; Trindade, Pablo

    2016-01-01

    Harmine is the β-carboline alkaloid with the highest concentration in the psychotropic plant decoction Ayahuasca. In rodents, classical antidepressants reverse the symptoms of depression by stimulating neuronal proliferation. It has been shown that Ayahuasca presents antidepressant effects in patients with depressive disorder. In the present study, we investigated the effects of harmine in cell cultures containing human neural progenitor cells (hNPCs, 97% nestin-positive) derived from pluripotent stem cells. After 4 days of treatment, the pool of proliferating hNPCs increased by 71.5%. Harmine has been reported as a potent inhibitor of the dual specificity tyrosine-phosphorylation-regulated kinase (DYRK1A), which regulates cell proliferation and brain development. We tested the effect of analogs of harmine, an inhibitor of DYRK1A (INDY), and an irreversible selective inhibitor of monoamine oxidase (MAO) but not DYRK1A (pargyline). INDY but not pargyline induced proliferation of hNPCs similarly to harmine, suggesting that inhibition of DYRK1A is a possible mechanism to explain harmine effects upon the proliferation of hNPCs. Our findings show that harmine enhances proliferation of hNPCs and suggest that inhibition of DYRK1A may explain its effects upon proliferation in vitro and antidepressant effects in vivo. PMID:27957390

  11. Harmine stimulates proliferation of human neural progenitors

    Directory of Open Access Journals (Sweden)

    Vanja Dakic

    2016-12-01

    Full Text Available Harmine is the β-carboline alkaloid with the highest concentration in the psychotropic plant decoction Ayahuasca. In rodents, classical antidepressants reverse the symptoms of depression by stimulating neuronal proliferation. It has been shown that Ayahuasca presents antidepressant effects in patients with depressive disorder. In the present study, we investigated the effects of harmine in cell cultures containing human neural progenitor cells (hNPCs, 97% nestin-positive derived from pluripotent stem cells. After 4 days of treatment, the pool of proliferating hNPCs increased by 71.5%. Harmine has been reported as a potent inhibitor of the dual specificity tyrosine-phosphorylation-regulated kinase (DYRK1A, which regulates cell proliferation and brain development. We tested the effect of analogs of harmine, an inhibitor of DYRK1A (INDY, and an irreversible selective inhibitor of monoamine oxidase (MAO but not DYRK1A (pargyline. INDY but not pargyline induced proliferation of hNPCs similarly to harmine, suggesting that inhibition of DYRK1A is a possible mechanism to explain harmine effects upon the proliferation of hNPCs. Our findings show that harmine enhances proliferation of hNPCs and suggest that inhibition of DYRK1A may explain its effects upon proliferation in vitro and antidepressant effects in vivo.

  12. Mitotic spindle orientation distinguishes stem cell and terminal modes of neuron production in the early spinal cord.

    Science.gov (United States)

    Wilcock, Arwen C; Swedlow, Jason R; Storey, Kate G

    2007-05-01

    Despite great insight into the molecular mechanisms that specify neuronal cell type in the spinal cord, cell behaviour underlying neuron production in this tissue is largely unknown. In other neuroepithelia, divisions with a perpendicular cleavage plane at the apical surface generate symmetrical cell fates, whereas a parallel cleavage plane generates asymmetric daughters, a neuron and a progenitor in a stem cell mode, and has been linked to the acquisition of neuron-generating ability. Using a novel long-term imaging assay, we have monitored single cells in chick spinal cord as they transit mitosis and daughter cells become neurons or divide again. We reveal new morphologies accompanying neuron birth and show that neurons are generated concurrently by asymmetric and terminal symmetric divisions. Strikingly, divisions that generate two progenitors or a progenitor and a neuron both exhibit a wide range of cleavage plane orientations and only divisions that produce two neurons have an exclusively perpendicular orientation. Neuron-generating progenitors are also distinguished by lengthening cell cycle times, a finding supported by cell cycle acceleration on exposure to fibroblast growth factor (FGF), an inhibitor of neuronal differentiation. This study provides a novel, dynamic view of spinal cord neurogenesis and supports a model in which cleavage plane orientation/mitotic spindle position does not assign neuron-generating ability, but functions subsequent to this step to distinguish stem cell and terminal modes of neuron production.

  13. The poster as modernist progenitor

    OpenAIRE

    Katherine Hauser

    2015-01-01

    Ruth E. Iskin’s The Poster: Art, Advertising. Design, and Collecting, 1860s-1900s positions the late-nineteenth-century advertising poster as the progenitor of valued modernist practices typically attached solely to photography and film. Modernist biases separating high art from mass culture account for scholars ignoring posters, however the poster ushered in an innovative reductive graphic style as well as pioneered the notion of multiple originals.

  14. The poster as modernist progenitor

    Directory of Open Access Journals (Sweden)

    Katherine Hauser

    2015-12-01

    Full Text Available Ruth E. Iskin’s The Poster: Art, Advertising. Design, and Collecting, 1860s-1900s positions the late-nineteenth-century advertising poster as the progenitor of valued modernist practices typically attached solely to photography and film. Modernist biases separating high art from mass culture account for scholars ignoring posters, however the poster ushered in an innovative reductive graphic style as well as pioneered the notion of multiple originals.

  15. Gamma-Ray Burst Progenitors

    Science.gov (United States)

    Levan, Andrew; Crowther, Paul; de Grijs, Richard; Langer, Norbert; Xu, Dong; Yoon, Sung-Chul

    2016-12-01

    We review our current understanding of the progenitors of both long and short duration gamma-ray bursts (GRBs). Constraints can be derived from multiple directions, and we use three distinct strands; (i) direct observations of GRBs and their host galaxies, (ii) parameters derived from modelling, both via population synthesis and direct numerical simulation and (iii) our understanding of plausible analog progenitor systems observed in the local Universe. From these joint constraints, we describe the likely routes that can drive massive stars to the creation of long GRBs, and our best estimates of the scenarios that can create compact object binaries which will ultimately form short GRBs, as well as the associated rates of both long and short GRBs. We further discuss how different the progenitors may be in the case of black hole engine or millisecond-magnetar models for the production of GRBs, and how central engines may provide a unifying theme between many classes of extremely luminous transient, from luminous and super-luminous supernovae to long and short GRBs.

  16. Gamma-ray burst progenitors

    CERN Document Server

    Levan, Andrew; de Grijs, Richard; Langer, Norbert; Xu, Dong; Yoon, Sung-Chul

    2016-01-01

    We review our current understanding of the progenitors of both long and short duration gamma-ray bursts (GRBs). Constraints can be derived from multiple directions, and we use three distinct strands; i) direct observations of GRBs and their host galaxies, ii) parameters derived from modeling, both via population synthesis and direct numerical simulation and iii) our understanding of plausible analog progenitor systems observed in the local Universe. From these joint constraints, we describe the likely routes that can drive massive stars to the creation of long GRBs, and our best estimates of the scenarios that can create compact object binaries which will ultimately form short GRBs, as well as the associated rates of both long and short GRBs. We further discuss how different the progenitors may be in the case of black hole engine or millisecond-magnetar models for the production of GRBs, and how central engines may provide a unifying theme between many classes of extremely luminous transient, from luminous an...

  17. A novel function of DELTA-NOTCH signalling mediates the transition from proliferation to neurogenesis in neural progenitor cells.

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    Barbara Hämmerle

    Full Text Available A complete account of the whole developmental process of neurogenesis involves understanding a number of complex underlying molecular processes. Among them, those that govern the crucial transition from proliferative (self-replicating to neurogenic neural progenitor (NP cells remain largely unknown. Due to its sequential rostro-caudal gradients of proliferation and neurogenesis, the prospective spinal cord of the chick embryo is a good experimental system to study this issue. We report that the NOTCH ligand DELTA-1 is expressed in scattered cycling NP cells in the prospective chick spinal cord preceding the onset of neurogenesis. These Delta-1-expressing progenitors are placed in between the proliferating caudal neural plate (stem zone and the rostral neurogenic zone (NZ where neurons are born. Thus, these Delta-1-expressing progenitors define a proliferation to neurogenesis transition zone (PNTZ. Gain and loss of function experiments carried by electroporation demonstrate that the expression of Delta-1 in individual progenitors of the PNTZ is necessary and sufficient to induce neuronal generation. The activation of NOTCH signalling by DELTA-1 in the adjacent progenitors inhibits neurogenesis and is required to maintain proliferation. However, rather than inducing cell cycle exit and neuronal differentiation by a typical lateral inhibition mechanism as in the NZ, DELTA-1/NOTCH signalling functions in a distinct manner in the PNTZ. Thus, the inhibition of NOTCH signalling arrests proliferation but it is not sufficient to elicit neuronal differentiation. Moreover, after the expression of Delta-1 PNTZ NP continue cycling and induce the expression of Tis21, a gene that is upregulated in neurogenic progenitors, before generating neurons. Together, these experiments unravel a novel function of DELTA-NOTCH signalling that regulates the transition from proliferation to neurogenesis in NP cells. We hypothesize that this novel function is evolutionary

  18. Neural progenitor cell apoptosis and differentiation were affected by activated microglia in spinal cord slice culture.

    Science.gov (United States)

    Liu, Xuqing; Chu, Tak-Ho; Su, Huanxing; Guo, Anchen; Wu, Wutian

    2014-03-01

    Neural progenitor cell (NPC) transplantation offers great potential to treat spinal cord injury (SCI). NPCs may replace lost neurons or oligodendrocytes and act as a source of neurotrophic factors to support survival of remaining cells. However, their efficiency was limited by poor survival after transplantation, and they tended more to differentiate into astrocytes, but not neurons and oligodendrocytes. This study investigated whether activated microglia is a factor that contributes to this phenomenon. Organotypic spinal cord slice (SCS) culture was used to mimic the local environment after SCI, and NPCs were co-cultured with them to share the culture medium. After specific depletion of microglia in the SCSs with clodronate loaded liposome, the apoptotic rate of NPCs decreased, more NPCs differentiated into neurons, and glial differentiation was impaired. This suggested that microglia may impair NPC survival, and neuronal differentiation, but improve astrocyte differentiation. In NPC transplantation strategy for SCI, microglia would be manipulated to improve the survival and neuronal differentiation of NPCs.

  19. Mechanisms of oligodendrocyte regeneration from ventricular-subventricular zone-derived progenitor cells in white matter diseases

    Directory of Open Access Journals (Sweden)

    Takakuni eMaki

    2013-12-01

    Full Text Available White matter dysfunction is an important part of many CNS disorders including multiple sclerosis and vascular dementia. Within injured areas, myelin loss and oligodendrocyte death may trigger endogenous attempts at regeneration. However, during disease progression, remyelination failure may eventually occur due to impaired survival/proliferation, migration/recruitment, and differentiation of oligodendrocyte precursor cells (OPCs. The ventricular-subventricular zone (V-SVZ and the subgranular zone are the main sources of neural stem/progenitor cells (NSPCs, which can give rise to neurons as well as OPCs. Under normal conditions in the adult brain, the V-SVZ progenitors generate a large number of neurons with a small number of oligodendrocyte lineage cells. However, after demyelination, the fate of V-SVZ-derived progenitor cells shifts from neurons to OPCs, and these newly generated OPCs migrate to the demyelinating lesions to ease white matter damage. In this mini-review, we will summarize the recent studies on extrinsic (e.g., vasculature, extracellular matrix, cerebrospinal fluid and intrinsic (e.g., transcription factors, epigenetic modifiers factors, which mediate oligodendrocyte generation from the V-SVZ progenitor cells. A deeper understanding of the mechanisms that regulate the fate of V-SVZ progenitor cells may lead to new therapeutic approaches for ameliorating white matter dysfunction and damage in CNS disorders.

  20. Specified neural progenitors sort to form sharp domains after noisy Shh signaling.

    Science.gov (United States)

    Xiong, Fengzhu; Tentner, Andrea R; Huang, Peng; Gelas, Arnaud; Mosaliganti, Kishore R; Souhait, Lydie; Rannou, Nicolas; Swinburne, Ian A; Obholzer, Nikolaus D; Cowgill, Paul D; Schier, Alexander F; Megason, Sean G

    2013-04-25

    Sharply delineated domains of cell types arise in developing tissues under instruction of inductive signal (morphogen) gradients, which specify distinct cell fates at different signal levels. The translation of a morphogen gradient into discrete spatial domains relies on precise signal responses at stable cell positions. However, cells in developing tissues undergoing morphogenesis and proliferation often experience complex movements, which may affect their morphogen exposure, specification, and positioning. How is a clear pattern achieved with cells moving around? Using in toto imaging of the zebrafish neural tube, we analyzed specification patterns and movement trajectories of neural progenitors. We found that specified progenitors of different fates are spatially mixed following heterogeneous Sonic Hedgehog signaling responses. Cell sorting then rearranges them into sharply bordered domains. Ectopically induced motor neuron progenitors also robustly sort to correct locations. Our results reveal that cell sorting acts to correct imprecision of spatial patterning by noisy inductive signals.

  1. Human-specific gene ARHGAP11B promotes basal progenitor amplification and neocortex expansion.

    Science.gov (United States)

    Florio, Marta; Albert, Mareike; Taverna, Elena; Namba, Takashi; Brandl, Holger; Lewitus, Eric; Haffner, Christiane; Sykes, Alex; Wong, Fong Kuan; Peters, Jula; Guhr, Elaine; Klemroth, Sylvia; Prüfer, Kay; Kelso, Janet; Naumann, Ronald; Nüsslein, Ina; Dahl, Andreas; Lachmann, Robert; Pääbo, Svante; Huttner, Wieland B

    2015-03-27

    Evolutionary expansion of the human neocortex reflects increased amplification of basal progenitors in the subventricular zone, producing more neurons during fetal corticogenesis. In this work, we analyze the transcriptomes of distinct progenitor subpopulations isolated by a cell polarity-based approach from developing mouse and human neocortex. We identify 56 genes preferentially expressed in human apical and basal radial glia that lack mouse orthologs. Among these, ARHGAP11B has the highest degree of radial glia-specific expression. ARHGAP11B arose from partial duplication of ARHGAP11A (which encodes a Rho guanosine triphosphatase-activating protein) on the human lineage after separation from the chimpanzee lineage. Expression of ARHGAP11B in embryonic mouse neocortex promotes basal progenitor generation and self-renewal and can increase cortical plate area and induce gyrification. Hence, ARHGAP11B may have contributed to evolutionary expansion of human neocortex.

  2. Spinal motor neurons are regenerated after mechanical lesion and genetic ablation in larval zebrafish

    Science.gov (United States)

    Ohnmacht, Jochen; Yang, Yujie; Maurer, Gianna W.; Barreiro-Iglesias, Antón; Tsarouchas, Themistoklis M.; Wehner, Daniel; Sieger, Dirk; Becker, Catherina G.; Becker, Thomas

    2016-01-01

    ABSTRACT In adult zebrafish, relatively quiescent progenitor cells show lesion-induced generation of motor neurons. Developmental motor neuron generation from the spinal motor neuron progenitor domain (pMN) sharply declines at 48 hours post-fertilisation (hpf). After that, mostly oligodendrocytes are generated from the same domain. We demonstrate here that within 48 h of a spinal lesion or specific genetic ablation of motor neurons at 72 hpf, the pMN domain reverts to motor neuron generation at the expense of oligodendrogenesis. By contrast, generation of dorsal Pax2-positive interneurons was not altered. Larval motor neuron regeneration can be boosted by dopaminergic drugs, similar to adult regeneration. We use larval lesions to show that pharmacological suppression of the cellular response of the innate immune system inhibits motor neuron regeneration. Hence, we have established a rapid larval regeneration paradigm. Either mechanical lesions or motor neuron ablation is sufficient to reveal a high degree of developmental flexibility of pMN progenitor cells. In addition, we show an important influence of the immune system on motor neuron regeneration from these progenitor cells. PMID:26965370

  3. A complete developmental sequence of a Drosophila neuronal lineage as revealed by twin-spot MARCM.

    Directory of Open Access Journals (Sweden)

    Hung-Hsiang Yu

    Full Text Available Drosophila brains contain numerous neurons that form complex circuits. These neurons are derived in stereotyped patterns from a fixed number of progenitors, called neuroblasts, and identifying individual neurons made by a neuroblast facilitates the reconstruction of neural circuits. An improved MARCM (mosaic analysis with a repressible cell marker technique, called twin-spot MARCM, allows one to label the sister clones derived from a common progenitor simultaneously in different colors. It enables identification of every single neuron in an extended neuronal lineage based on the order of neuron birth. Here we report the first example, to our knowledge, of complete lineage analysis among neurons derived from a common neuroblast that relay olfactory information from the antennal lobe (AL to higher brain centers. By identifying the sequentially derived neurons, we found that the neuroblast serially makes 40 types of AL projection neurons (PNs. During embryogenesis, one PN with multi-glomerular innervation and 18 uniglomerular PNs targeting 17 glomeruli of the adult AL are born. Many more PNs of 22 additional types, including four types of polyglomerular PNs, derive after the neuroblast resumes dividing in early larvae. Although different offspring are generated in a rather arbitrary sequence, the birth order strictly dictates the fate of each post-mitotic neuron, including the fate of programmed cell death. Notably, the embryonic progenitor has an altered temporal identity following each self-renewing asymmetric cell division. After larval hatching, the same progenitor produces multiple neurons for each cell type, but the number of neurons for each type is tightly regulated. These observations substantiate the origin-dependent specification of neuron types. Sequencing neuronal lineages will not only unravel how a complex brain develops but also permit systematic identification of neuron types for detailed structure and function analysis of the

  4. S100B and APP promote a gliocentric shift and impaired neurogenesis in Down syndrome neural progenitors.

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    Jie Lu

    Full Text Available Down syndrome (DS is a developmental disorder associated with mental retardation (MR and early onset Alzheimer's disease (AD. These CNS phenotypes are attributed to ongoing neuronal degeneration due to constitutive overexpression of chromosome 21 (HSA21 genes. We have previously shown that HSA21 associated S100B contributes to oxidative stress and apoptosis in DS human neural progenitors (HNPs. Here we show that DS HNPs isolated from fetal frontal cortex demonstrate not only disturbances in redox states within the mitochondria and increased levels of progenitor cell death but also transition to more gliocentric progenitor phenotypes with a consequent reduction in neuronogenesis. HSA21 associated S100B and amyloid precursor protein (APP levels are simultaneously increased within DS HNPs, their secretions are synergistically enhanced in a paracrine fashion, and overexpressions of these proteins disrupt mitochondrial membrane potentials and redox states. HNPs show greater susceptibility to these proteins as compared to neurons, leading to cell death. Ongoing inflammation through APP and S100B overexpression further promotes a gliocentric HNPs phenotype. Thus, the loss in neuronal numbers seen in DS is not merely due to increased HNPs cell death and neurodegeneration, but also a fundamental gliocentric shift in the progenitor pool that impairs neuronal production.

  5. S100B and APP promote a gliocentric shift and impaired neurogenesis in Down syndrome neural progenitors.

    Science.gov (United States)

    Lu, Jie; Esposito, Giuseppe; Scuderi, Caterina; Steardo, Luca; Delli-Bovi, Laurent C; Hecht, Jonathan L; Dickinson, Bryan C; Chang, Christopher J; Mori, Takashi; Sheen, Volney

    2011-01-01

    Down syndrome (DS) is a developmental disorder associated with mental retardation (MR) and early onset Alzheimer's disease (AD). These CNS phenotypes are attributed to ongoing neuronal degeneration due to constitutive overexpression of chromosome 21 (HSA21) genes. We have previously shown that HSA21 associated S100B contributes to oxidative stress and apoptosis in DS human neural progenitors (HNPs). Here we show that DS HNPs isolated from fetal frontal cortex demonstrate not only disturbances in redox states within the mitochondria and increased levels of progenitor cell death but also transition to more gliocentric progenitor phenotypes with a consequent reduction in neuronogenesis. HSA21 associated S100B and amyloid precursor protein (APP) levels are simultaneously increased within DS HNPs, their secretions are synergistically enhanced in a paracrine fashion, and overexpressions of these proteins disrupt mitochondrial membrane potentials and redox states. HNPs show greater susceptibility to these proteins as compared to neurons, leading to cell death. Ongoing inflammation through APP and S100B overexpression further promotes a gliocentric HNPs phenotype. Thus, the loss in neuronal numbers seen in DS is not merely due to increased HNPs cell death and neurodegeneration, but also a fundamental gliocentric shift in the progenitor pool that impairs neuronal production.

  6. ApoE is required for maintenance of the dentate gyrus neural progenitor pool

    Science.gov (United States)

    Yang, Cui-Ping; Gilley, Jennifer A.; Zhang, Gui; Kernie, Steven G.

    2011-01-01

    Many genes regulating adult neurogenesis have been identified and are known to play similar roles during early neuronal development. We recently identified apolipoprotein E (ApoE) as a gene the expression of which is essentially absent in early brain progenitors but becomes markedly upregulated in adult dentate gyrus stem/progenitor cells. Here, we demonstrate that ApoE deficiency impairs adult dentate gyrus development by affecting the neural progenitor pool over time. We utilized ApoE-deficient mice crossed to a nestin-GFP reporter to demonstrate that dentate gyrus progenitor cells proliferate more rapidly at early ages, which is subsequently accompanied by an overall decrease in neural progenitor cell number at later time points. This appears to be secondary to over-proliferation early in life and ultimate depletion of the Type 1 nestin- and GFAP-expressing neural stem cells. We also rescue the proliferation phenotype with an ApoE-expressing retrovirus, demonstrating that ApoE works directly in this regard. These data provide novel insight into late hippocampal development and suggest a possible role for ApoE in neurodegenerative diseases. PMID:21880781

  7. Lineage tracing of neuromesodermal progenitors reveals novel Wnt-dependent roles in trunk progenitor cell maintenance and differentiation

    National Research Council Canada - National Science Library

    Garriock, Robert J; Chalamalasetty, Ravindra B; Kennedy, Mark W; Canizales, Lauren C; Lewandoski, Mark; Yamaguchi, Terry P

    2015-01-01

    ...) of the trunk region while suppressing neural specification. Recent lineage-tracing experiments have demonstrated that these trunk neural progenitors and PMPs derive from a common multipotent progenitor called the neuromesodermal progenitor (NMP...

  8. AKT signaling mediates IGF-I survival actions on otic neural progenitors.

    Directory of Open Access Journals (Sweden)

    Maria R Aburto

    Full Text Available BACKGROUND: Otic neurons and sensory cells derive from common progenitors whose transition into mature cells requires the coordination of cell survival, proliferation and differentiation programmes. Neurotrophic support and survival of post-mitotic otic neurons have been intensively studied, but the bases underlying the regulation of programmed cell death in immature proliferative otic neuroblasts remains poorly understood. The protein kinase AKT acts as a node, playing a critical role in controlling cell survival and cell cycle progression. AKT is activated by trophic factors, including insulin-like growth factor I (IGF-I, through the generation of the lipidic second messenger phosphatidylinositol 3-phosphate by phosphatidylinositol 3-kinase (PI3K. Here we have investigated the role of IGF-dependent activation of the PI3K-AKT pathway in maintenance of otic neuroblasts. METHODOLOGY/PRINCIPAL FINDINGS: By using a combination of organotypic cultures of chicken (Gallus gallus otic vesicles and acoustic-vestibular ganglia, Western blotting, immunohistochemistry and in situ hybridization, we show that IGF-I-activation of AKT protects neural progenitors from programmed cell death. IGF-I maintains otic neuroblasts in an undifferentiated and proliferative state, which is characterised by the upregulation of the forkhead box M1 (FoxM1 transcription factor. By contrast, our results indicate that post-mitotic p27(Kip-positive neurons become IGF-I independent as they extend their neuronal processes. Neurons gradually reduce their expression of the Igf1r, while they increase that of the neurotrophin receptor, TrkC. CONCLUSIONS/SIGNIFICANCE: Proliferative otic neuroblasts are dependent on the activation of the PI3K-AKT pathway by IGF-I for survival during the otic neuronal progenitor phase of early inner ear development.

  9. HIV-1 alters neural and glial progenitor cell dynamics in the central nervous system: coordinated response to opiates during maturation.

    Science.gov (United States)

    Hahn, Yun Kyung; Podhaizer, Elizabeth M; Hauser, Kurt F; Knapp, Pamela E

    2012-12-01

    HIV-associated neurocognitive disorders (HANDs) are common sequelae of human immunodeficiency virus (HIV) infection, even when viral titers are well controlled by antiretroviral therapy. Evidence in patients and animal models suggests that neurologic deficits are increased during chronic opiate exposure. We have hypothesized that central nervous system (CNS) progenitor cells in both adult and developing CNS are affected by HIV infection and that opiates exacerbate these effects. To examine this question, neural progenitors were exposed to HIV-1 Tat(1-86) in the developing brain of inducible transgenic mice and in vitro. We examined whether Tat affected the proliferation or balance of progenitor populations expressing nestin, Sox2, and Olig2. Disease relevance was further tested by exposing human-derived progenitors to supernatant from HIV-1 infected monocytes. Studies concentrated on striatum, a region preferentially targeted by HIV and opiates. Results were similar among experimental paradigms. Tat or HIV exposure reduced the proliferation of undifferentiated (Sox2(+)) progenitors and oligodendroglial (Olig2(+)) progenitors. Coexposure to morphine exacerbated the effects of Tat or HIV-1(SF162) supernatant, but partially reversed HIV-1(IIIB) supernatant effects. Populations of Sox2(+) and Olig2(+) cells were also reduced by Tat exposure, although progenitor survival was unaffected. In rare instances, p24 immunolabeling was detected in viable human progenitors by confocal imaging. The vulnerability of progenitors is likely to distort the dynamic balance among neuron/glial populations as the brain matures, perhaps contributing to reports that neurologic disease is especially prevalent in pediatric HIV patients. Pediatric disease is atypical in developed regions but remains a serious concern in resource-limited areas where infection occurs commonly at birth and through breast feeding.

  10. Distinct efficacy of pre-differentiated versus intact fetal mesencephalon-derived human neural progenitor cells in alleviating rat model of Parkinson's disease

    Institute of Scientific and Technical Information of China (English)

    XuanWang; YanyanLu; HuanqingZhang; KunWang; QihuaHe; YueWang; XianyuLiu; LinsongLi; XiaominWang

    2005-01-01

    Neural progenitor cells have shown tile effectiveness in the treatment of Parkinson's disease, but tile therapeutic efficacy remains variable. One of important factors that determine the efficacy is the necessity ofpre-differentiation of progenitor cells into dopaminergic neurons before transplantation. This study therefore investigated the therapeutic efficacy of mesencephalon-derived human neural progenitor cells with or without the pre-differentiation in alleviating a rat model of Parkinson's disease. We found that a combination of 50ng/ml fibroblast growth factor 8, 10ng/ml glial cell line-derived neurotrophic factor and 10μM forskolin facilitated the differentiation of human fetal mesencephalic progenitor cells into dopaminergic neurons in vitro. More importantly, after transplanted into the striatum ofparkinsonian rats, only pre-differentiated grafts resulted in an elevated production ofdopamine in the transplanted site and the amelioration of behavioral impairments of the parkinsonian rats. Unlike pre-differentiated progenitors, grafted intactprogenitors rarely differentiated into dopaminergic neurons in vivo and emigrated actively away from the transplanted site. These data demonstrates the importance ofpre-differentiation of human progenitor cells before transplantation in enhancing therapeutic potency for Parkinson's disease.

  11. Assessing the efficacy of endoscopic office olfactory biopsy sites to produce neural progenitor cell cultures for the study of neuropsychiatric disorders.

    Science.gov (United States)

    Wrobel, Bozena B; Mazza, Jill M; Evgrafov, Oleg V; Knowles, James A

    2013-02-01

    The olfactory region is capable of continuous neurogenesis. Situated on the cribriform plate and segments of the superior septum and both superior and middle turbinates, it is accessible through office-based biopsy and can be used to generate neural progenitor cells to study molecular abnormalities associated with neuropsychiatric disorders. The purpose of the study was to evaluate the efficacy of the endoscopic office olfactory biopsy from middle turbinate and superior-posterior septum to produce the neural progenitor cells. Endoscopic office-based biopsy samples were collected and cultured neuronal cells derived from olfactory neuroepithelium (CNON) were established from 40 healthy individuals and 40 schizophrenia patients. All patients underwent biopsies of both the middle turbinate and the superior-posterior septum. Specific culture conditions promoted the growth of neural progenitor cells from these biopsy sites. CNON cultures were established from such outgrowing neuronal cells. The study was institutional review board (IRB)-approved and informed consent was obtained. Cultures were successfully developed from 98.8% of participants. No complications were observed. The single, unsuccessful specimen failed to grow any cell types due to tissue mishandling. Overall, we have observed no significant difference in the effectiveness of biopsy from middle turbinate and superior-posterior septum to produce neural progenitor cells. The middle turbinate biopsies contain viable neural progenitor cells capable of generating neuronal cell cultures. Thus technically more simple biopsy of the middle turbinate can be used to propagate neural progenitor cells. © 2013 ARS-AAOA, LLC.

  12. Dynamic Pax6 expression during the neurogenic cell cycle influences proliferation and cell fate choices of retinal progenitors

    Directory of Open Access Journals (Sweden)

    Yang Xian-Jie

    2009-08-01

    Full Text Available Abstract Background The paired homeobox protein Pax6 is essential for proliferation and pluripotency of retinal progenitors. However, temporal changes in Pax6 protein expression associated with the generation of various retinal neurons have not been characterized with regard to the cell cycle. Here, we examine the dynamic changes of Pax6 expression among chicken retinal progenitors as they progress through the neurogenic cell cycle, and determine the effects of altered Pax6 levels on retinogenesis. Results We provide evidence that during the preneurogenic to neurogenic transition, Pax6 protein levels in proliferating progenitor cells are down-regulated. Neurogenic retinal progenitors retain a relatively low level of Pax6 protein, whereas postmitotic neurons either elevate or extinguish Pax6 expression in a cell type-specific manner. Cell imaging and cell cycle analyses show that neurogenic progenitors in the S phase of the cell cycle contain low levels of Pax6 protein, whereas a subset of progenitors exhibits divergent levels of Pax6 protein upon entering the G2 phase of the cell cycle. We also show that M phase cells contain varied levels of Pax6, and some correlate with the onset of early neuronal marker expression, forecasting cell cycle exit and cell fate commitment. Furthermore, either elevating or knocking down Pax6 attenuates cell proliferation and results in increased cell death. Reducing Pax6 decreases retinal ganglion cell genesis and enhances cone photoreceptor and amacrine interneuron production, whereas elevating Pax6 suppresses cone photoreceptor and amacrine cell fates. Conclusion These studies demonstrate for the first time quantitative changes in Pax6 protein expression during the preneurogenic to neurogenic transition and during the neurogenic cell cycle. The results indicate that Pax6 protein levels are stringently controlled in proliferating progenitors. Maintaining a relatively low Pax6 protein level is necessary for S phase

  13. Sonic hedgehog signaling regulates mode of cell division of early cerebral cortex progenitors and increases astrogliogenesis

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    Geissy LL Araújo

    2014-03-01

    Full Text Available The morphogen Sonic Hedgehog (SHH plays a critical role in the development of different tissues. In the central nervous system, SHH is well known to contribute to the patterning of the spinal cord and separation of the brain hemispheres. In addition, it has recently been shown that SHH signaling also contributes to the patterning of the telencephalon and establishment of adult neurogenic niches. In this work, we investigated whether SHH signaling influences the behavior of neural progenitors isolated from the dorsal telencephalon, which generate excitatory neurons and macroglial cells in vitro. We observed that SHH increases proliferation of cortical progenitors and generation of astrocytes, whereas blocking SHH signaling with cyclopamine has opposite effects. In both cases, generation of neurons did not seem to be affected. However, cell survival was broadly affected by blockade of SHH signaling. SHH effects were related to three different cell phenomena: mode of cell division, cell cycle length and cell growth. Together, our data in vitro demonstrate that SHH signaling controls cell behaviors that are important for proliferation of cerebral cortex progenitors, as well as differentiation and survival of neurons and astroglial cells.

  14. Migration of bone marrow progenitor cells in the adult brain of rats and rabbits.

    Science.gov (United States)

    Dennie, Donnahue; Louboutin, Jean-Pierre; Strayer, David S

    2016-04-26

    Neurogenesis takes place in the adult mammalian brain in three areas: Subgranular zone of the dentate gyrus (DG); subventricular zone of the lateral ventricle; olfactory bulb. Different molecular markers can be used to characterize the cells involved in adult neurogenesis. It has been recently suggested that a population of bone marrow (BM) progenitor cells may migrate to the brain and differentiate into neuronal lineage. To explore this hypothesis, we injected recombinant SV40-derived vectors into the BM and followed the potential migration of the transduced cells. Long-term BM-directed gene transfer using recombinant SV40-derived vectors leads to expression of the genes delivered to the BM firstly in circulating cells, then after several months in mature neurons and microglial cells, and thus without central nervous system (CNS) lesion. Most of transgene-expressing cells expressed NeuN, a marker of mature neurons. Thus, BM-derived cells may function as progenitors of CNS cells in adult animals. The mechanism by which the cells from the BM come to be neurons remains to be determined. Although the observed gradual increase in transgene-expressing neurons over 16 mo suggests that the pathway involved differentiation of BM-resident cells into neurons, cell fusion as the principal route cannot be totally ruled out. Additional studies using similar viral vectors showed that BM-derived progenitor cells migrating in the CNS express markers of neuronal precursors or immature neurons. Transgene-positive cells were found in the subgranular zone of the DG of the hippocampus 16 mo after intramarrow injection of the vector. In addition to cells expressing markers of mature neurons, transgene-positive cells were also positive for nestin and doublecortin, molecules expressed by developing neuronal cells. These cells were actively proliferating, as shown by short term BrdU incorporation studies. Inducing seizures by using kainic acid increased the number of BM progenitor cells

  15. Isolation and differentiation of neural stem/progenitor cells from fetal rat dorsal root ganglia

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    To find a promising alternative to neurons or schwann cells (SCs) for peripheral nerve repair applications,this study sought to isolate stem cells from fetal rat dorsal root ganglion (DRG) explants.Molecular expression analysis confirmed neural stem cell characteristics of DRG-derived neurospheres in terms of expressing neural stem cell-specific genes and a set of well-defined genes related to stem cell niches and glial fate decision.Under the influence of neurotrophic factors,bFGF and NGF,the neurospheres gave rise to neurofilament-expressing neurons and S100-expressing Schwann cell-like cells by different pathways.This study suggests that a subpopulation of stem cells that reside in DRGs is the progenitor of neurons and glia,which could directly induce the differentiation toward neurons,or SCs.

  16. Migration of bone marrow progenitor cells in the adult brain of rats and rabbits

    Institute of Scientific and Technical Information of China (English)

    Donnahue; Dennie; Jean-Pierre; Louboutin; David; S; Strayer

    2016-01-01

    Neurogenesis takes place in the adult mammalian brain in three areas:Subgranular zone of the dentate gyrus(DG);subventricular zone of the lateral ventricle;olfactory bulb.Different molecular markers can be used to characterizethe cells involved in adult neurogenesis.It has been recently suggested that a population of bone marrow(BM)progenitor cells may migrate to the brain and differentiate into neuronal lineage.To explore this hypothesis,we injected recombinant SV40-derived vectors into the BM and followed the potential migration of the transduced cells.Long-term BM-directed gene transfer using recombinant SV40-derived vectors leads to expression of the genes delivered to the BM firstly in circulating cells,then after several months in mature neurons and microglial cells,and thus without central nervous system(CNS)lesion.Most of transgene-expressing cells expressed NeuN,a marker of mature neurons.Thus,BM-derived cells may function as progenitors of CNS cells in adult animals.The mechanism by which the cells from the BM come to be neurons remains to be determined.Although the observed gradual increase in transgene-expressing neurons over 16mo suggests that the pathway involved differentiation of BM-resident cells into neurons,cell fusion as the principal route cannot be totally ruled out.Additional studies using similar viral vectors showed that BM-derived progenitor cells migrating in the CNS express markers of neuronal precursors or immature neurons.Transgene-positive cells were found in the subgranular zone of the DG of the hippocampus 16 mo after intramarrow injection of the vector.In addition to cells expressing markers of mature neurons,transgene-positive cells were also positive for nestin and doublecortin,molecules expressed by developing neuronal cells.These cells were actively proliferating,as shown by short term BrdU incorporation studies.Inducing seizures by using kainic acid increased the number of BM progenitor cells transduced by SV40vectors

  17. Impact of Lipid Nutrition on Neural Stem/Progenitor Cells

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    Nobuyuki Sakayori

    2013-01-01

    Full Text Available The neural system originates from neural stem/progenitor cells (NSPCs. Embryonic NSPCs first proliferate to increase their numbers and then produce neurons and glial cells that compose the complex neural circuits in the brain. New neurons are continually produced even after birth from adult NSPCs in the inner wall of the lateral ventricle and in the hippocampal dentate gyrus. These adult-born neurons are involved in various brain functions, including olfaction-related functions, learning and memory, pattern separation, and mood control. NSPCs are regulated by various intrinsic and extrinsic factors. Diet is one of such important extrinsic factors. Of dietary nutrients, lipids are important because they constitute the cell membrane, are a source of energy, and function as signaling molecules. Metabolites of some lipids can be strong lipid mediators that also regulate various biological activities. Recent findings have revealed that lipids are important regulators of both embryonic and adult NSPCs. We and other groups have shown that lipid signals including fat, fatty acids, their metabolites and intracellular carriers, cholesterol, and vitamins affect proliferation and differentiation of embryonic and adult NSPCs. A better understanding of the NSPCs regulation by lipids may provide important insight into the neural development and brain function.

  18. Interface dynamos in supernova progenitors

    CERN Document Server

    Blackman, E G; Thomas, J H; Blackman, Eric G.; Nordhaus, Jason T.; Thomas, John H.

    2004-01-01

    Observational evidence for anisotropy in supernovae (SN) and their phenomenological connection to jetted sources such as gamma-ray bursts^Mhave revived considerations of the role magnetohydrodynamic outflows might play therein. Understanding the types of dynamos that might operate in supernova progenitors is therefore relevant. In contrast to previous work, here we study an ``interface dynamo'' for the conditions of a rapidly rotating neutron star surrounded by a convective envelope. Such dynamos have been studied for the Sun, naked white dwarfs,and post-AGB stars, where analogous configurations of strong shear layers surrounded by convective envelopes are present. The interface dynamo provides estimates of large-scale poloidal and toroidal fields, whose product enters the Poynting flux. Because the poloidal field is much weaker than the toroidal magnetic field, the actual average Poynting flux is lower than rough estimates which invoke the only the magnitude of the total magnetic energy. The lower value is s...

  19. Progenitors of Supernovae Type Ia

    CERN Document Server

    Toonen, S; Bours, M; Zwart, S Portegies; Claeys, J; Mennekens, N; Ruiter, A

    2013-01-01

    Despite the significance of Type Ia supernovae (SNeIa) in many fields in astrophysics, SNeIa lack a theoretical explanation. The standard scenarios involve thermonuclear explosions of carbon/oxygen white dwarfs approaching the Chandrasekhar mass; either by accretion from a companion or by a merger of two white dwarfs. We investigate the contribution from both channels to the SNIa rate with the binary population synthesis (BPS) code SeBa in order to constrain binary processes such as the mass retention efficiency of WD accretion and common envelope evolution. We determine the theoretical rates and delay time distribution of SNIa progenitors and in particular study how assumptions affect the predicted rates.

  20. Derivation of multipotent progenitors from human circulating CD14+ monocytes.

    Science.gov (United States)

    Seta, Noriyuki; Kuwana, Masataka

    2010-07-01

    Circulating CD14(+) monocytes are originated from hematopoietic stem cells in the bone marrow and believed to be committed precursors for phagocytes, such as macrophages. Recently, we have reported a primitive cell population termed monocyte-derived multipotential cells (MOMCs), which has a fibroblast-like morphology in culture and a unique phenotype positive for CD14, CD45, CD34, and type I collagen. MOMCs are derived from circulating CD14(+) monocytes, but circulating precursors for MOMCs still remain undetermined. Comparative analysis of gene expression profiles of MOMCs and other monocyte-derived cells has revealed that embryonic stem cell markers, Nanog and Oct-4, are specifically expressed by MOMCs. In vitro generation of MOMCs requires binding to fibronectin and exposure to soluble factors derived from activated platelets. MOMCs contain progenitors with capacity to differentiate into a variety of nonphagocytes, including bone, cartilage, fat, skeletal and cardiac muscle, neuron, and endothelium, indicating that circulating monocytes are more multipotent than previously thought. In addition, MOMCs are capable of promoting ex vivo expansion of human hematopoietic progenitor cells through direct cell-to-cell contact and secretion of a variety of hematopoietic growth factors. These findings obtained from the research on MOMCs indicate that CD14(+) monocytes in circulation are involved in a variety of physiologic functions other than innate and acquired immune responses, such as repair and regeneration of the damaged tissue.

  1. Permeability transition pore-mediated mitochondrial superoxide flashes regulate cortical neural progenitor differentiation.

    Science.gov (United States)

    Hou, Yan; Mattson, Mark P; Cheng, Aiwu

    2013-01-01

    In the process of neurogenesis, neural progenitor cells (NPCs) cease dividing and differentiate into postmitotic neurons that grow dendrites and an axon, become excitable, and establish synapses with other neurons. Mitochondrial biogenesis and aerobic metabolism provide energy substrates required to support the differentiation, growth and synaptic activity of neurons. Mitochondria may also serve signaling functions and, in this regard, it was recently reported that mitochondria can generate rapid bursts of superoxide (superoxide flashes), the frequency of which changes in response to environmental conditions and signals including oxygen levels and Ca(2+) fluxes. Here we show that the frequency of mitochondrial superoxide flashes increases as embryonic cerebral cortical neurons differentiate from NPCs, and provide evidence that the superoxide flashes serve a signaling function that is critical for the differentiation process. The superoxide flashes are mediated by mitochondrial permeability transition pore (mPTP) opening, and pharmacological inhibition of the mPTP suppresses neuronal differentiation. Moreover, superoxide flashes and neuronal differentiation are inhibited by scavenging of mitochondrial superoxide. Conversely, manipulations that increase superoxide flash frequency accelerate neuronal differentiation. Our findings reveal a regulatory role for mitochondrial superoxide flashes, mediated by mPTP opening, in neuronal differentiation.

  2. Derivation of neurons with functional properties from adult limbal epithelium: implications in autologous cell therapy for photoreceptor degeneration.

    Science.gov (United States)

    Zhao, Xing; Das, Ani V; Bhattacharya, Sumitra; Thoreson, Wallace B; Sierra, Jorge Rodriguez; Mallya, Kavita B; Ahmad, Iqbal

    2008-04-01

    The limbal epithelium (LE), a circular and narrow epithelium that separates cornea from conjunctiva, harbors stem cells/progenitors in its basal layer that regenerate cornea. We have previously demonstrated that cells in the basal LE, when removed from their niche and cultured in reduced bond morphogenetic protein signaling, acquire properties of neural progenitors. Here, we demonstrate that LE-derived neural progenitors generate neurons with functional properties and can be directly differentiated along rod photoreceptor lineage in vitro and in vivo. These observations posit the LE as a potential source of neural progenitors for autologous cell therapy to treat photoreceptor degeneration in age-related macular degeneration and retinitis pigmentosa.

  3. The early postnatal nonhuman primate neocortex contains self-renewing multipotent neural progenitor cells.

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    Jihane Homman-Ludiye

    Full Text Available The postnatal neocortex has traditionally been considered a non-neurogenic region, under non-pathological conditions. A few studies suggest, however, that a small subpopulation of neural cells born during postnatal life can differentiate into neurons that take up residence within the neocortex, implying that postnatal neurogenesis could occur in this region, albeit at a low level. Evidence to support this hypothesis remains controversial while the source of putative neural progenitors responsible for generating new neurons in the postnatal neocortex is unknown. Here we report the identification of self-renewing multipotent neural progenitor cells (NPCs derived from the postnatal day 14 (PD14 marmoset monkey primary visual cortex (V1, striate cortex. While neuronal maturation within V1 is well advanced by PD14, we observed cells throughout this region that co-expressed Sox2 and Ki67, defining a population of resident proliferating progenitor cells. When cultured at low density in the presence of epidermal growth factor (EGF and/or fibroblast growth factor 2 (FGF-2, dissociated V1 tissue gave rise to multipotent neurospheres that exhibited the ability to differentiate into neurons, oligodendrocytes and astrocytes. While the capacity to generate neurones and oligodendrocytes was not observed beyond the third passage, astrocyte-restricted neurospheres could be maintained for up to 6 passages. This study provides the first direct evidence for the existence of multipotent NPCs within the postnatal neocortex of the nonhuman primate. The potential contribution of neocortical NPCs to neural repair following injury raises exciting new possibilities for the field of regenerative medicine.

  4. The early postnatal nonhuman primate neocortex contains self-renewing multipotent neural progenitor cells.

    Science.gov (United States)

    Homman-Ludiye, Jihane; Merson, Tobias D; Bourne, James A

    2012-01-01

    The postnatal neocortex has traditionally been considered a non-neurogenic region, under non-pathological conditions. A few studies suggest, however, that a small subpopulation of neural cells born during postnatal life can differentiate into neurons that take up residence within the neocortex, implying that postnatal neurogenesis could occur in this region, albeit at a low level. Evidence to support this hypothesis remains controversial while the source of putative neural progenitors responsible for generating new neurons in the postnatal neocortex is unknown. Here we report the identification of self-renewing multipotent neural progenitor cells (NPCs) derived from the postnatal day 14 (PD14) marmoset monkey primary visual cortex (V1, striate cortex). While neuronal maturation within V1 is well advanced by PD14, we observed cells throughout this region that co-expressed Sox2 and Ki67, defining a population of resident proliferating progenitor cells. When cultured at low density in the presence of epidermal growth factor (EGF) and/or fibroblast growth factor 2 (FGF-2), dissociated V1 tissue gave rise to multipotent neurospheres that exhibited the ability to differentiate into neurons, oligodendrocytes and astrocytes. While the capacity to generate neurones and oligodendrocytes was not observed beyond the third passage, astrocyte-restricted neurospheres could be maintained for up to 6 passages. This study provides the first direct evidence for the existence of multipotent NPCs within the postnatal neocortex of the nonhuman primate. The potential contribution of neocortical NPCs to neural repair following injury raises exciting new possibilities for the field of regenerative medicine.

  5. Multipotent adult progenitor cell conditions enhance human adipose-derived stem cells’ ability to protect retinal neurons%多能成体祖细胞培养条件促进人脂肪干细胞的视网膜神经保护功能

    Institute of Scientific and Technical Information of China (English)

    娄慧; 徐国旭

    2014-01-01

    目的:检测多能成体祖细胞(MAPC)的培养条件对猴骨髓间充质细胞(BMMSCs)和人脂肪干细胞(hADSCs)生长的影响,旨在获得更适合治疗视网膜变性疾病的供体细胞。方法通过细胞形态观察、MTT实验、克隆形成率、PCR检测、以及成脂、成骨、成软骨分化潜能检测等,研究MAPC培养条件下猴BMMSCs和hADSCs的特征,并用DMEM/LG和MAPC培养条件培养的hADSCs进行RCS大鼠视网膜下腔移植,通过视网膜电图(ERG)和TUNEL检测,判断细胞移植治疗对视功能及视网膜细胞凋亡的影响。结果与常规培养基相比,MAPC培养条件能促进猴BMMSCs增殖,细胞变小,但传2代后,细胞变得宽大扁平,出现衰老征象;然而,MAPC培养条件下的hADSCs细胞增殖能力及克隆形成率均增强,形成的克隆较大可稳定传10代以上,且具有成脂、成骨、成软骨的多向分化潜能,细胞表面标记物及细胞因子出现差异表达:CD140b、CD90、CD47、HGF和PEDF显著上调,CD73、CD105和IL-6显著下调。与对照组相比,移植DMEM/LG和MAPC培养条件培养的hADSCs(P4)3周后,RCS大鼠的B波波幅明显升高,外核层细胞凋亡明显减少。结论 MAPC培养条件培养的hADSCs显示出更好的视网膜神经保护作用,适合用于治疗视网膜退行性疾病。%Objective To investigate the effects of multipotent adult progenitor cell (MAPC) conditions on biological characteristics and therapeutic effects of monkey bone marrow mesenchymal stem cells (BMMSCs) and human adipose-derived stem cells (hADSCs), thus to obtain optimal donor cells for treatment of retinal degeneration (RD). Methods The cell morphology, MTT assay, clone formation, adipogenic, osteogenic, chondrogenic differentiation potential and qRT-PCR technique were used to detect biological characteristics of monkey BMMSCs and hADSCs. The hADSCs were cultured under MAPC condition medium and transplanted into

  6. Transplanted Neural Progenitor Cells from Distinct Sources Migrate Differentially in an Organotypic Model of Brain Injury

    Science.gov (United States)

    Ngalula, Kapinga P.; Cramer, Nathan; Schell, Michael J.; Juliano, Sharon L.

    2015-01-01

    Brain injury is a major cause of long-term disability. The possibility exists for exogenously derived neural progenitor cells to repair damage resulting from brain injury, although more information is needed to successfully implement this promising therapy. To test the ability of neural progenitor cells (NPCs) obtained from rats to repair damaged neocortex, we transplanted neural progenitor cell suspensions into normal and injured slice cultures of the neocortex acquired from rats on postnatal day 0–3. Donor cells from E16 embryos were obtained from either the neocortex, including the ventricular zone (VZ) for excitatory cells, ganglionic eminence (GE) for inhibitory cells or a mixed population of the two. Cells were injected into the ventricular/subventricular zone (VZ/SVZ) or directly into the wounded region. Transplanted cells migrated throughout the cortical plate with GE and mixed population donor cells predominately targeting the upper cortical layers, while neocortically derived NPCs from the VZ/SVZ migrated less extensively. In the injured neocortex, transplanted cells moved predominantly into the wounded area. NPCs derived from the GE tended to be immunoreactive for GABAergic markers while those derived from the neocortex were more strongly immunoreactive for other neuronal markers such as MAP2, TUJ1, or Milli-Mark. Cells transplanted in vitro acquired the electrophysiological characteristics of neurons, including action potential generation and reception of spontaneous synaptic activity. This suggests that transplanted cells differentiate into neurons capable of functionally integrating with the host tissue. Together, our data suggest that transplantation of neural progenitor cells holds great potential as an emerging therapeutic intervention for restoring function lost to brain damage. PMID:26500604

  7. Morphine Modulates Adult Neurogenesis and Contextual Memory by Impeding the Maturation of Neural Progenitors.

    Science.gov (United States)

    Zhang, Yue; Xu, Chi; Zheng, Hui; Loh, Horace H; Law, Ping-Yee

    2016-01-01

    The regulation of adult neurogenesis by opiates has been implicated in modulating different addiction cycles. At which neurogenesis stage opiates exert their action remains unresolved. We attempt to define the temporal window of morphine's inhibition effect on adult neurogenesis by using the POMC-EGFP mouse model, in which newborn granular cells (GCs) can be visualized between days 3-28 post-mitotic. The POMC-EGFP mice were trained under the 3-chambers conditioned place preference (CPP) paradigm with either saline or morphine. We observed after 4 days of CPP training with saline, the number of EGFP-labeled newborn GCs in sub-granular zone (SGZ) hippocampus significantly increased compared to mice injected with saline in their homecage. CPP training with morphine significantly decreased the number of EGFP-labeled GCs, whereas no significant difference in the number of EGFP-labeled GCs was observed with the homecage mice injected with the same dose of morphine. Using cell-type selective markers, we observed that morphine reduced the number of late stage progenitors and immature neurons such as Doublecortin (DCX) and βIII Tubulin (TuJ1) positive cells in the SGZ but did not reduce the number of early progenitors such as Nestin, SOX2, or neurogenic differentiation-1 (NeuroD1) positive cells. Analysis of co-localization between different cell markers shows that morphine reduced the number of adult-born GCs by interfering with differentiation of early progenitors, but not by inducing apoptosis. In addition, when NeuroD1 was over-expressed in DG by stereotaxic injection of lentivirus, it rescued the loss of immature neurons and prolonged the extinction of morphine-trained CPP. These results suggest that under the condition of CPP training paradigm, morphine affects the transition of neural progenitor/stem cells to immature neurons via a mechanism involving NeuroD1.

  8. Transplanted neural progenitor cells from distinct sources migrate differentially in an organotypic model of brain injury

    Directory of Open Access Journals (Sweden)

    Kapinga eNgalula

    2015-10-01

    Full Text Available Brain injury is a major cause of long-term disability. The possibility exists for exogenously derived neural progenitor cells to repair damage resulting from brain injury, although more information is needed to successfully implement this promising therapy. To test the ability of neural progenitor cells (NPCs obtained from rats to repair damaged neocortex, we transplanted neural progenitor cell suspensions into normal and injured slice cultures of the neocortex acquired from rats on postnatal day 0-3. Donor cells from E16 embryos were obtained from either the neocortex, including the ventricular zone (VZ for excitatory cells, ganglionic eminence (GE for inhibitory cells or a mixed population of the two. Cells were injected into the ventricular/subventricular zone (VZ/SVZ or directly into the wounded region. Transplanted cells migrated throughout the cortical plate with GE and mixed population donor cells predominately targeting the upper cortical layers, while neocortically derived NPCs from the VZ/SVZ migrated less extensively. In the injured neocortex, transplanted cells moved predominantly into the wounded area. NPCs derived from the GE tended to be immunoreactive for GABAergic markers while those derived from the neocortex were more strongly immunoreactive for other neuronal markers such as MAP2, TUJ1, or Milli-Mark. Cells transplanted in vitro acquired the electrophysiological characteristics of neurons, including action potential generation and reception of spontaneous synaptic activity. This suggests that transplanted cells differentiate into neurons capable of functionally integrating with the host tissue. Together, our data suggest that transplantation of neural progenitor cells holds great potential as an emerging therapeutic intervention for restoring function lost to brain damage.

  9. β-catenin/Wnt signaling controls progenitor fate in the developing and regenerating zebrafish retina

    Directory of Open Access Journals (Sweden)

    Meyers Jason R

    2012-08-01

    Full Text Available Abstract Background The zebrafish retina maintains two populations of stem cells: first, the germinal zone or ciliary marginal zone (CMZ contains multipotent retinal progenitors that add cells to the retinal periphery as the fish continue to grow; second, radial glia (Müller cells occasionally divide asymmetrically to generate committed progenitors that differentiate into rod photoreceptors, which are added interstitially throughout the retina with growth. Retinal injury stimulates Müller glia to dedifferentiate, re-enter the cell cycle, and generate multipotent retinal progenitors similar to those in the CMZ to replace missing neurons. The specific signals that maintain these two distinct populations of endogenous retinal stem cells are not understood. Results We used genetic and pharmacological manipulation of the β-catenin/Wnt signaling pathway to show that it is required to maintain proliferation in the CMZ and that hyperstimulation of β-catenin/Wnt signaling inhibits normal retinal differentiation and expands the population of proliferative retinal progenitors. To test whether similar effects occur during regeneration, we developed a method for making rapid, selective photoreceptor ablations in larval zebrafish with intense light. We found that dephosphorylated β-catenin accumulates in Müller glia as they re-enter the cell cycle following injury, but not in Müller glia that remain quiescent. Activation of Wnt signaling is required for regenerative proliferation, and hyperstimulation results in loss of Müller glia from the INL as all proliferative cells move into the ONL. Conclusions β-catenin/Wnt signaling is thus required for the maintenance of retinal progenitors during both initial development and lesion-induced regeneration, and is sufficient to prevent differentiation of those progenitors and maintain them in a proliferative state. This suggests that the β-catenin/Wnt cascade is part of the shared molecular circuitry that

  10. The Contradictory Effects of Neuronal Hyperexcitationon Adult Hippocampal Neurogenesis.

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    Juan Manuel Encinas

    2016-03-01

    Full Text Available Adult hippocampal neurogenesis is a highly plastic process that responds swiftly to neuronal activity. Adult hippocampal neurogenesis can be regulated at the level of neural stem cell recruitment and activation, progenitor proliferation, as well as newborn cell survival and differentiation. An excitation-neurogenesis rule was proposed after the demonstration of the capability of cultured neural stem and progenitor cells to intrinsically sense neuronal excitatory activity. In vivo, this property has remained elusive although recently the direct response of neural stem cells to GABA in the hippocampus via GABAA receptors has evidenced a mechanism for a direct talk between neurons and neural stem cells. As it is pro-neurogenic, the effect of excitatory neuronal activity has been generally considered beneficial. But what happens in situations of neuronal hyperactivity in which neurogenesis can be dramatically boosted? In animal models, electroconvulsive shock markedly increases neurogenesis. On the contrary, in epilepsy rodent models, seizures induce the generation of misplaced neurons with abnormal morphological and electrophysiological properties, namely aberrant neurogenesis. We will herein discuss what is known about the mechanisms of influence of neurons on neural stem cells, as well as the severe effects of neuronal hyperexcitation on hippocampal neurogenesis.

  11. Preclinical Analysis of Fetal Human Mesencephalic Neural Progenitor Cell Lines: Characterization and Safety In Vitro and In Vivo.

    Science.gov (United States)

    Moon, Jisook; Schwarz, Sigrid C; Lee, Hyun-Seob; Kang, Jun Mo; Lee, Young-Eun; Kim, Bona; Sung, Mi-Young; Höglinger, Günter; Wegner, Florian; Kim, Jin Su; Chung, Hyung-Min; Chang, Sung Woon; Cha, Kwang Yul; Kim, Kwang-Soo; Schwarz, Johannes

    2016-09-02

    : We have developed a good manufacturing practice for long-term cultivation of fetal human midbrain-derived neural progenitor cells. The generation of human dopaminergic neurons may serve as a tool of either restorative cell therapies or cellular models, particularly as a reference for phenotyping region-specific human neural stem cell lines such as human embryonic stem cells and human inducible pluripotent stem cells. We cultivated 3 different midbrain neural progenitor lines at 10, 12, and 14 weeks of gestation for more than a year and characterized them in great detail, as well as in comparison with Lund mesencephalic cells. The whole cultivation process of tissue preparation, cultivation, and cryopreservation was developed using strict serum-free conditions and standardized operating protocols under clean-room conditions. Long-term-cultivated midbrain-derived neural progenitor cells retained stemness, midbrain fate specificity, and floorplate markers. The potential to differentiate into authentic A9-specific dopaminergic neurons was markedly elevated after prolonged expansion, resulting in large quantities of functional dopaminergic neurons without genetic modification. In restorative cell therapeutic approaches, midbrain-derived neural progenitor cells reversed impaired motor function in rodents, survived well, and did not exhibit tumor formation in immunodeficient nude mice in the short or long term (8 and 30 weeks, respectively). We conclude that midbrain-derived neural progenitor cells are a promising source for human dopaminergic neurons and suitable for long-term expansion under good manufacturing practice, thus opening the avenue for restorative clinical applications or robust cellular models such as high-content or high-throughput screening.

  12. Differentiation of neurons from neural precursors generated in floating spheres from embryonic stem cells

    Directory of Open Access Journals (Sweden)

    Forrester Jeff

    2009-09-01

    Full Text Available Abstract Background Neural differentiation of embryonic stem (ES cells is usually achieved by induction of ectoderm in embryoid bodies followed by the enrichment of neuronal progenitors using a variety of factors. Obtaining reproducible percentages of neural cells is difficult and the methods are time consuming. Results Neural progenitors were produced from murine ES cells by a combination of nonadherent conditions and serum starvation. Conversion to neural progenitors was accompanied by downregulation of Oct4 and NANOG and increased expression of nestin. ES cells containing a GFP gene under the control of the Sox1 regulatory regions became fluorescent upon differentiation to neural progenitors, and ES cells with a tau-GFP fusion protein became fluorescent upon further differentiation to neurons. Neurons produced from these cells upregulated mature neuronal markers, or differentiated to glial and oligodendrocyte fates. The neurons gave rise to action potentials that could be recorded after application of fixed currents. Conclusion Neural progenitors were produced from murine ES cells by a novel method that induced neuroectoderm cells by a combination of nonadherent conditions and serum starvation, in contrast to the embryoid body method in which neuroectoderm cells must be selected after formation of all three germ layers.

  13. Mirror neurons

    National Research Council Canada - National Science Library

    Rubia Vila, Francisco José

    2011-01-01

    Mirror neurons were recently discovered in frontal brain areas of the monkey. They are activated when the animal makes a specific movement, but also when the animal observes the same movement in another animal...

  14. Hematopoietic progenitor migration to the adult thymus

    OpenAIRE

    Zlotoff, Daniel A.; Bhandoola, Avinash

    2011-01-01

    While most hematopoietic lineages develop in the bone marrow (BM), T cells uniquely complete their development in the specialized environment of the thymus. Hematopoietic stem cells with long-term self-renewal capacity are not present in the thymus. As a result, continuous T cell development requires that BM-derived progenitors be imported into the thymus throughout adult life. The process of thymic homing begins with the mobilization of progenitors out of the bone marrow, continues with thei...

  15. Supernova Remnant Progenitor Masses in M31

    CERN Document Server

    Jennings, Zachary G; Murphy, Jeremiah W; Dalcanton, Julianne J; Gilbert, Karoline M; Dolphin, Andrew E; Fouesneau, Morgan; Weisz, Daniel R

    2012-01-01

    Using HST photometry, we age-date 59 supernova remnants (SNRs) in the spiral galaxy M31 and use these ages to estimate zero-age main sequence masses (MZAMS) for their progenitors. To accomplish this, we create color-magnitude diagrams (CMDs) and use CMD fitting to measure the recent star formation history (SFH) of the regions surrounding cataloged SNR sites. We identify any young coeval population that likely produced the progenitor star and assign an age and uncertainty to that population. Application of stellar evolution models allows us to infer the MZAMS from this age. Because our technique is not contingent on precise location of the progenitor star, it can be applied to the location of any known SNR. We identify significant young SF around 53 of the 59 SNRs and assign progenitor masses to these, representing a factor of 2 increase over currently measured progenitor masses. We consider the remaining 6 SNRs as either probable Type Ia candidates or the result of core-collapse progenitors that have escaped ...

  16. Immunocytochemical characterisation of neural stem-progenitor cells from green terror cichlid Aequidens rivulatus.

    Science.gov (United States)

    Wen, C M; Chen, M M; Nan, F H; Wang, C S

    2017-01-01

    In this study, cultures of neural stem-progenitor cells (NSPC) from the brain of green terror cichlid Aequidens rivulatus were established and various NSPCs were demonstrated using immunocytochemistry. All of the NSPCs expressed brain lipid-binding protein, dopamine- and cAMP-regulated neuronal phosphoprotein 32 (DARPP-32), oligodendrocyte transcription factor 2, paired box 6 and sex determining region Y-box 2. The intensity and localisation of these proteins, however, varied among the different NSPCs. Despite being intermediate cells, NSPCs can be divided into radial glial cells, oligodendrocyte progenitor cells (OPC) and neuroblasts by expressing the astrocyte marker glial fibrillary acidic protein (GFAP), OPC marker A2B5 and neuronal markers, including acetyl-tubulin, βIII-tubulin, microtubule-associated protein 2 and neurofilament protein. Nevertheless, astrocytes were polymorphic and were the most dominant cells in the NSPC cultures. By using Matrigel, radial glia exhibiting a long GFAP(+) or DARPP-32(+) fibre and neurons exhibiting a significant acetyl-tubulin(+) process were obtained. The results confirmed that NSPCs obtained from A. rivulatus brains can proliferate and differentiate into neurons in vitro. Clonal culture can be useful for further studying the distinct NSPCs.

  17. Neurons derive from the more apical daughter in asymmetric divisions in the zebrafish neural tube.

    Science.gov (United States)

    Alexandre, Paula; Reugels, Alexander M; Barker, David; Blanc, Eric; Clarke, Jonathan D W

    2010-06-01

    In the developing CNS, asymmetric cell division is critical for maintaining the balanced production of differentiating neurons while renewing the population of neural progenitors. In invertebrates, this process depends on asymmetric inheritance of fate determinants during progenitor divisions. A similar mechanism is widely believed to underlie asymmetrically fated divisions in vertebrates, but compelling evidence for this is missing. We used live imaging of individual progenitors in the intact zebrafish embryo CNS to test this hypothesis. We found that asymmetric inheritance of a subcellular domain is strongly correlated with asymmetric daughter fates and our results reveal an unexpected feature of this process. The daughter cell destined to become a neuron was derived from the more apical of the two daughters, whereas the more basal daughter inherited the basal process and replenished the apical progenitor pool.

  18. Cortical neurogenesis in adult rats after ischemic brain injury:most new neurons fail to mature

    Institute of Scientific and Technical Information of China (English)

    Qing-quan Li; Guan-qun Qiao; Jun Ma; Hong-wei Fan; Ying-bin Li

    2015-01-01

    The present study examines the hypothesis that endogenous neural progenitor cells isolated from the neocortex of ischemic brain can differentiate into neurons or glial cells and contribute to neural regeneration. We performed middle cerebral artery occlusion to establish a model of cerebral ischemia/reperfusion injury in adult rats. Immunohistochemical staining of the cortex 1, 3, 7, 14 or 28 days after injury revealed that neural progenitor cells double-positive for nestin and sox-2 appeared in the injured cortex 1 and 3 days post-injury, and were also positive for glial ifbrillary acidic protein. New neurons were labeled using bromodeoxyuridine and different stages of maturity were identiifed using doublecortin, microtubule-associated protein 2 and neuronal nuclei antigen immunohistochemistry. Immature new neurons coexpressing doublecortin and bromodeoxyuridine were observed in the cortex at 3 and 7 days post-injury, and semi-mature and mature new neurons double-positive for microtubule-associated protein 2 and bromode-oxyuridine were found at 14 days post-injury. A few mature new neurons coexpressing neuronal nuclei antigen and bromodeoxyuridine were observed in the injured cortex 28 days post-injury. Glial ifbrillary acidic protein/bromodeoxyuridine double-positive astrocytes were also found in the injured cortex. Our ifndings suggest that neural progenitor cells are present in the damaged cortex of adult rats with cerebral ischemic brain injury, and that they differentiate into astrocytes and immature neurons, but most neurons fail to reach the mature stage.

  19. Specification of Region-Specific Neurons Including Forebrain Glutamatergic Neurons from Human Induced Pluripotent Stem Cells

    Science.gov (United States)

    Martins-Taylor, Kristen; Wang, Xiaofang; Zhang, Zheng; Park, Jung Woo; Zhan, Shuning; Kronenberg, Mark S.; Lichtler, Alexander; Liu, Hui-Xia; Chen, Fang-Ping; Yue, Lixia; Li, Xue-Jun; Xu, Ren-He

    2010-01-01

    Background Directed differentiation of human induced pluripotent stem cells (hiPSC) into functional, region-specific neural cells is a key step to realizing their therapeutic promise to treat various neural disorders, which awaits detailed elucidation. Methodology/Principal Findings We analyzed neural differentiation from various hiPSC lines generated by others and ourselves. Although heterogeneity in efficiency of neuroepithelial (NE) cell differentiation was observed among different hiPSC lines, the NE differentiation process resembles that from human embryonic stem cells (hESC) in morphology, timing, transcriptional profile, and requirement for FGF signaling. NE cells differentiated from hiPSC, like those from hESC, can also form rostral phenotypes by default, and form the midbrain or spinal progenitors upon caudalization by morphogens. The rostrocaudal neural progenitors can further mature to develop forebrain glutamatergic projection neurons, midbrain dopaminergic neurons, and spinal motor neurons, respectively. Typical ion channels and action potentials were recorded in the hiPSC-derived neurons. Conclusions/Significance Our results demonstrate that hiPSC, regardless of how they were derived, can differentiate into a spectrum of rostrocaudal neurons with functionality, which supports the considerable value of hiPSC for study and treatment of patient-specific neural disorders. PMID:20686615

  20. Specification of region-specific neurons including forebrain glutamatergic neurons from human induced pluripotent stem cells.

    Directory of Open Access Journals (Sweden)

    Hui Zeng

    Full Text Available BACKGROUND: Directed differentiation of human induced pluripotent stem cells (hiPSC into functional, region-specific neural cells is a key step to realizing their therapeutic promise to treat various neural disorders, which awaits detailed elucidation. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed neural differentiation from various hiPSC lines generated by others and ourselves. Although heterogeneity in efficiency of neuroepithelial (NE cell differentiation was observed among different hiPSC lines, the NE differentiation process resembles that from human embryonic stem cells (hESC in morphology, timing, transcriptional profile, and requirement for FGF signaling. NE cells differentiated from hiPSC, like those from hESC, can also form rostral phenotypes by default, and form the midbrain or spinal progenitors upon caudalization by morphogens. The rostrocaudal neural progenitors can further mature to develop forebrain glutamatergic projection neurons, midbrain dopaminergic neurons, and spinal motor neurons, respectively. Typical ion channels and action potentials were recorded in the hiPSC-derived neurons. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that hiPSC, regardless of how they were derived, can differentiate into a spectrum of rostrocaudal neurons with functionality, which supports the considerable value of hiPSC for study and treatment of patient-specific neural disorders.

  1. Meis1 regulates Foxn4 expression during retinal progenitor cell differentiation

    Directory of Open Access Journals (Sweden)

    Mohammed M. Islam

    2013-09-01

    The transcription factor forkhead box N4 (Foxn4 is a key regulator in a variety of biological processes during development. In particular, Foxn4 plays an essential role in the genesis of horizontal and amacrine neurons from neural progenitors in the vertebrate retina. Although the functions of Foxn4 have been well established, the transcriptional regulation of Foxn4 expression during progenitor cell differentiation remains unclear. Here, we report that an evolutionarily conserved 129 bp noncoding DNA fragment (Foxn4CR4.2 or CR4.2, located ∼26 kb upstream of Foxn4 transcription start site, functions as a cis-element for Foxn4 regulation. CR4.2 directs gene expression in Foxn4-positive cells, primarily in progenitors, differentiating horizontal and amacrine cells. We further determined that the gene regulatory activity of CR4.2 is modulated by Meis1 binding motif, which is bound and activated by Meis1 transcription factor. Deletion of the Meis1 binding motif or knockdown of Meis1 expression abolishes the gene regulatory activity of CR4.2. In addition, knockdown of Meis1 expression diminishes the endogenous Foxn4 expression and affects cell lineage development. Together, we demonstrate that CR4.2 and its interacting Meis1 transcription factor play important roles in regulating Foxn4 expression during early retinogenesis. These findings provide new insights into molecular mechanisms that govern gene regulation in retinal progenitors and specific cell lineage development.

  2. Up-regulation of DRP-3 long isoform during the induction of neural progenitor cells by glutamate treatment in the ex vivo rat retina

    Energy Technology Data Exchange (ETDEWEB)

    Tokuda, Kazuhiro, E-mail: r502um@yamaguchi-u.ac.jp [Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi (Japan); Department of Biochemistry and Functional Proteomics, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi (Japan); Kuramitsu, Yasuhiro; Byron, Baron; Kitagawa, Takao [Department of Biochemistry and Functional Proteomics, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi (Japan); Tokuda, Nobuko [Faculty of Health Sciences, Yamaguchi University Graduate School of Medicine, Ube (Japan); Kobayashi, Daiki; Nagayama, Megumi; Araki, Norie [Department of Tumor Genetics and Biology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto (Japan); Sonoda, Koh-Hei [Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi (Japan); Nakamura, Kazuyuki [Department of Biochemistry and Functional Proteomics, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi (Japan)

    2015-08-07

    Glutamate has been shown to induce neural progenitor cells in the adult vertebrate retina. However, protein dynamics during progenitor cell induction by glutamate are not fully understood. To identify specific proteins involved in the process, we employed two-dimensional electrophoresis-based proteomics on glutamate untreated and treated retinal ex vivo sections. Rat retinal tissues were incubated with 1 mM glutamate for 1 h, followed by incubation in glutamate-free media for a total of 24 h. Consistent with prior reports, it was found that mitotic cells appeared in the outer nuclear layer without any histological damage. Immunohistological evaluations and immunoblotting confirmed the emergence of neuronal progenitor cells in the mature retina treated with glutamate. Proteomic analysis revealed the up-regulation of dihydropyrimidinase-related protein 3 (DRP-3), DRP-2 and stress-induced-phosphoprotein 1 (STIP1) during neural progenitor cell induction by glutamate. Moreover, mRNA expression of DRP-3, especially, its long isoform, robustly increased in the treated retina compared to that in the untreated retina. These results may indicate that glutamate induces neural progenitor cells in the mature rat retina by up-regulating the proteins which mediate cell mitosis and neurite growth. - Highlights: • Glutamate induced neuronal progenitor cells in the mature rat retina. • Proteomic analysis revealed the up-regulation of DRP-3, DRP-2 and STIP1. • mRNA expression of DRP-3, especially, its long isoform, robustly increased.

  3. Histone deacetylases 1 and 2 control the progression of neural precursors to neurons during brain development

    Science.gov (United States)

    Montgomery, Rusty L.; Hsieh, Jenny; Barbosa, Ana C.; Richardson, James A.; Olson, Eric N.

    2009-01-01

    The molecular mechanism by which neural progenitor cells commit to a specified lineage of the central nervous system remains unknown. We show that HDAC1 and HDAC2 redundantly control neuronal development and are required for neuronal specification. Mice lacking HDAC1 or HDAC2 in neuronal precursors show no overt histoarchitectural phenotypes, whereas deletion of both HDAC1 and HDAC2 in developing neurons results in severe hippocampal abnormalities, absence of cerebellar foliation, disorganization of cortical neurons, and lethality by postnatal day 7. These abnormalities in brain formation can be attributed to a failure of neuronal precursors to differentiate into mature neurons and to excessive cell death. These results reveal redundant and essential roles for HDAC1 and HDAC2 in the progression of neuronal precursors to mature neurons in vivo. PMID:19380719

  4. PACAP Promotes Matrix-Driven Adhesion of Cultured Adult Murine Neural Progenitors

    Directory of Open Access Journals (Sweden)

    James A. Waschek

    2017-05-01

    Full Text Available New neurons are born throughout the life of mammals in germinal zones of the brain known as neurogenic niches: the subventricular zone of the lateral ventricles and the subgranular zone of the dentate gyrus of the hippocampus. These niches contain a subpopulation of cells known as adult neural progenitor cells (aNPCs, which self-renew and give rise to new neurons and glia. aNPCs are regulated by many factors present in the niche, including the extracellular matrix (ECM. We show that the neuropeptide PACAP (pituitary adenylate cyclase-activating polypeptide affects subventricular zone-derived aNPCs by increasing their surface adhesion. Gene array and reconstitution assays indicate that this effect can be attributed to the regulation of ECM components and ECM-modifying enzymes in aNPCs by PACAP. Our work suggests that PACAP regulates a bidirectional interaction between the aNPCs and their niche: PACAP modifies ECM production and remodeling, in turn the ECM regulates progenitor cell adherence. We speculate that PACAP may in this manner help restrict adult neural progenitors to the stem cell niche in vivo, with potential significance for aNPC function in physiological and pathological states.

  5. Effects of Chronic Low-Dose Radiation on Human Neural Progenitor Cells

    Science.gov (United States)

    Katsura, Mari; Cyou-Nakamine, Hiromasa; Zen, Qin; Zen, Yang; Nansai, Hiroko; Amagasa, Shota; Kanki, Yasuharu; Inoue, Tsuyoshi; Kaneki, Kiyomi; Taguchi, Akashi; Kobayashi, Mika; Kaji, Toshiyuki; Kodama, Tatsuhiko; Miyagawa, Kiyoshi; Wada, Youichiro; Akimitsu, Nobuyoshi; Sone, Hideko

    2016-01-01

    The effects of chronic low-dose radiation on human health have not been well established. Recent studies have revealed that neural progenitor cells are present not only in the fetal brain but also in the adult brain. Since immature cells are generally more radiosensitive, here we investigated the effects of chronic low-dose radiation on cultured human neural progenitor cells (hNPCs) derived from embryonic stem cells. Radiation at low doses of 31, 124 and 496 mGy per 72 h was administered to hNPCs. The effects were estimated by gene expression profiling with microarray analysis as well as morphological analysis. Gene expression was dose-dependently changed by radiation. By thirty-one mGy of radiation, inflammatory pathways involving interferon signaling and cell junctions were altered. DNA repair and cell adhesion molecules were affected by 124 mGy of radiation while DNA synthesis, apoptosis, metabolism, and neural differentiation were all affected by 496 mGy of radiation. These in vitro results suggest that 496 mGy radiation affects the development of neuronal progenitor cells while altered gene expression was observed at a radiation dose lower than 100 mGy. This study would contribute to the elucidation of the clinical and subclinical phenotypes of impaired neuronal development induced by chronic low-dose radiation. PMID:26795421

  6. Effects of Chronic Low-Dose Radiation on Human Neural Progenitor Cells

    Science.gov (United States)

    Katsura, Mari; Cyou-Nakamine, Hiromasa; Zen, Qin; Zen, Yang; Nansai, Hiroko; Amagasa, Shota; Kanki, Yasuharu; Inoue, Tsuyoshi; Kaneki, Kiyomi; Taguchi, Akashi; Kobayashi, Mika; Kaji, Toshiyuki; Kodama, Tatsuhiko; Miyagawa, Kiyoshi; Wada, Youichiro; Akimitsu, Nobuyoshi; Sone, Hideko

    2016-01-01

    The effects of chronic low-dose radiation on human health have not been well established. Recent studies have revealed that neural progenitor cells are present not only in the fetal brain but also in the adult brain. Since immature cells are generally more radiosensitive, here we investigated the effects of chronic low-dose radiation on cultured human neural progenitor cells (hNPCs) derived from embryonic stem cells. Radiation at low doses of 31, 124 and 496 mGy per 72 h was administered to hNPCs. The effects were estimated by gene expression profiling with microarray analysis as well as morphological analysis. Gene expression was dose-dependently changed by radiation. By thirty-one mGy of radiation, inflammatory pathways involving interferon signaling and cell junctions were altered. DNA repair and cell adhesion molecules were affected by 124 mGy of radiation while DNA synthesis, apoptosis, metabolism, and neural differentiation were all affected by 496 mGy of radiation. These in vitro results suggest that 496 mGy radiation affects the development of neuronal progenitor cells while altered gene expression was observed at a radiation dose lower than 100 mGy. This study would contribute to the elucidation of the clinical and subclinical phenotypes of impaired neuronal development induced by chronic low-dose radiation.

  7. Effects of Chronic Low-Dose Radiation on Human Neural Progenitor Cells.

    Science.gov (United States)

    Katsura, Mari; Cyou-Nakamine, Hiromasa; Zen, Qin; Zen, Yang; Nansai, Hiroko; Amagasa, Shota; Kanki, Yasuharu; Inoue, Tsuyoshi; Kaneki, Kiyomi; Taguchi, Akashi; Kobayashi, Mika; Kaji, Toshiyuki; Kodama, Tatsuhiko; Miyagawa, Kiyoshi; Wada, Youichiro; Akimitsu, Nobuyoshi; Sone, Hideko

    2016-01-22

    The effects of chronic low-dose radiation on human health have not been well established. Recent studies have revealed that neural progenitor cells are present not only in the fetal brain but also in the adult brain. Since immature cells are generally more radiosensitive, here we investigated the effects of chronic low-dose radiation on cultured human neural progenitor cells (hNPCs) derived from embryonic stem cells. Radiation at low doses of 31, 124 and 496 mGy per 72 h was administered to hNPCs. The effects were estimated by gene expression profiling with microarray analysis as well as morphological analysis. Gene expression was dose-dependently changed by radiation. By thirty-one mGy of radiation, inflammatory pathways involving interferon signaling and cell junctions were altered. DNA repair and cell adhesion molecules were affected by 124 mGy of radiation while DNA synthesis, apoptosis, metabolism, and neural differentiation were all affected by 496 mGy of radiation. These in vitro results suggest that 496 mGy radiation affects the development of neuronal progenitor cells while altered gene expression was observed at a radiation dose lower than 100 mGy. This study would contribute to the elucidation of the clinical and subclinical phenotypes of impaired neuronal development induced by chronic low-dose radiation.

  8. Mitogen and stress-activated kinases 1/2 regulate ischemia-induced hippocampal progenitor cell proliferation and neurogenesis.

    Science.gov (United States)

    Karelina, K; Liu, Y; Alzate-Correa, D; Wheaton, K L; Hoyt, K R; Arthur, J S C; Obrietan, K

    2015-01-29

    Pathophysiological conditions such as cerebral ischemia trigger the production of new neurons from the neurogenic niche within the subgranular zone (SGZ) of the dentate gyrus. The functional significance of ischemia-induced neurogenesis is believed to be the regeneration of lost cells, thus contributing to post-ischemia recovery. However, the cell signaling mechanisms by which this process is regulated are still under investigation. Here, we investigated the role of mitogen and stress-activated protein kinases (MSK1/2) in the regulation of progenitor cell proliferation and neurogenesis after cerebral ischemia. Using the endothelin-1 model of ischemia, wild-type (WT) and MSK1(-/-)/MSK2(-/-) (MSK dKO) mice were injected with BrdU and sacrificed 2 days, 4 weeks, or 6 weeks later for the analysis of progenitor cell proliferation, neurogenesis, and neuronal morphology, respectively. We report a decrease in SGZ progenitor cell proliferation in MSK dKO mice compared to WT mice. Moreover, MSK dKO mice exhibited reduced neurogenesis and a delayed maturation of ischemia-induced newborn neurons. Further, structural analysis of neuronal arborization revealed reduced branching complexity in MSK dKO compared to WT mice. Taken together, this dataset suggests that MSK1/2 plays a significant role in the regulation of ischemia-induced progenitor cell proliferation and neurogenesis. Ultimately, revealing the cell signaling mechanisms that promote neuronal recovery will lead to novel pharmacological approaches for the treatment of neurodegenerative diseases such as cerebral ischemia. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

  9. Intermediate Progenitors Facilitate Intracortical Progression of Thalamocortical Axons and Interneurons through CXCL12 Chemokine Signaling.

    Science.gov (United States)

    Abe, Philipp; Molnár, Zoltán; Tzeng, Yi-Shiuan; Lai, Dar-Ming; Arnold, Sebastian J; Stumm, Ralf

    2015-09-23

    Glutamatergic principal neurons, GABAergic interneurons and thalamocortical axons (TCAs) are essential elements of the cerebrocortical network. Principal neurons originate locally from radial glia and intermediate progenitors (IPCs), whereas interneurons and TCAs are of extrinsic origin. Little is known how the assembly of these elements is coordinated. C-X-C motif chemokine 12 (CXCL12), which is known to guide axons outside the neural tube and interneurons in the cortex, is expressed in the meninges and IPCs. Using mouse genetics, we dissected the influence of IPC-derived CXCL12 on TCAs and interneurons by showing that Cxcl12 ablation in IPCs, leaving meningeal Cxcl12 intact, attenuates intracortical TCA growth and disrupts tangential interneuron migration in the subventricular zone. In accordance with strong CXCR4 expression in the forming thalamus and TCAs, we identified a CXCR4-dependent growth-promoting effect of CXCL12 on TCAs in thalamus explants. Together, our findings indicate a cell-autonomous role of CXCR4 in promoting TCA growth. We propose that CXCL12 signals from IPCs link cortical neurogenesis to the progression of TCAs and interneurons spatially and temporally. Significance statement: The cerebral cortex exerts higher brain functions including perceptual and emotional processing. Evolutionary expansion of the mammalian cortex is mediated by intermediate progenitors, transient amplifying cells generating cortical excitatory neurons. During the peak period of cortical neurogenesis, migrating precursors of inhibitory interneurons originating in subcortical areas and thalamic axons invade the cortex. Although defects in the assembly of cortical network elements cause neurological and mental disorders, little is known how neurogenesis, interneuron recruitment, and axonal ingrowth are coordinated. We demonstrate that intermediate progenitors release the chemotactic cytokine CXCL12 to promote intracortical interneuron migration and growth of thalamic axons

  10. Neurovascular Recovery via Cotransplanted Neural and Vascular Progenitors Leads to Improved Functional Restoration after Ischemic Stroke in Rats

    Directory of Open Access Journals (Sweden)

    Jia Li

    2014-07-01

    Full Text Available The concept of the “neurovascular unit,” emphasizing the interactions between neural and vascular components in the brain, raised the notion that neural progenitor cell (NPC transplantation therapy aimed at neural repair may be insufficient for the treatment of ischemic stroke. Here, we demonstrate that enhanced neurovascular recovery via cotransplantation of NPCs and embryonic stem cell-derived vascular progenitor cells (VPCs in a rat stroke model is correlated with improved functional recovery after stroke. We found that cotransplantation promoted the survival, migration, differentiation, and maturation of neuronal and vascular cells derived from the cotransplanted progenitors. Furthermore, it triggered an increased generation of VEGF-, BDNF-, and IGF1-expressing neural cells derived from the grafted NPCs. Consistently, compared with transplantation of NPCs alone, cotransplantation more effectively improved the neurobehavioral deficits and attenuated the infarct volume. Thus, cotransplantation of NPCs and VPCs represents a more effective therapeutic strategy for the treatment of stroke than transplantation of NPCs alone.

  11. Terminal Differentiation of Adult Hippocampal Progenitor Cells Is a Step Functionally Dissociable from Proliferation and Is Controlled by Tis21, Id3 and NeuroD2

    Science.gov (United States)

    Micheli, Laura; Ceccarelli, Manuela; Gioia, Roberta; D’Andrea, Giorgio; Farioli-Vecchioli, Stefano; Costanzi, Marco; Saraulli, Daniele; Cestari, Vincenzo; Tirone, Felice

    2017-01-01

    Cell proliferation and differentiation are interdependent processes. Here, we have asked to what extent the two processes of neural progenitor cell amplification and differentiation are functionally separated. Thus, we analyzed whether it is possible to rescue a defect of terminal differentiation in progenitor cells of the dentate gyrus, where new neurons are generated throughout life, by inducing their proliferation and/or their differentiation with different stimuli appropriately timed. As a model we used the Tis21 knockout mouse, whose dentate gyrus neurons, as demonstrated by us and others, have an intrinsic defect of terminal differentiation. We first tested the effect of two proliferative as well as differentiative neurogenic stimuli, one pharmacological (fluoxetine), the other cognitive (the Morris water maze (MWM) training). Both effectively enhanced the number of new dentate gyrus neurons produced, and fluoxetine also reduced the S-phase length of Tis21 knockout dentate gyrus progenitor cells and increased the rate of differentiation of control cells, but neither factor enhanced the defective rate of differentiation. In contrast, the defect of terminal differentiation was fully rescued by in vivo infection of proliferating dentate gyrus progenitor cells with retroviruses either silencing Id3, an inhibitor of neural differentiation, or expressing NeuroD2, a proneural gene expressed in terminally differentiated dentate gyrus neurons. This is the first demonstration that NeuroD2 or the silencing of Id3 can activate the differentiation of dentate gyrus neurons, complementing a defect of differentiation. It also highlights how the rate of differentiation of dentate gyrus neurons is regulated genetically at several levels and that a neurogenic stimulus for amplification of neural stem/progenitor cells may not be sufficient in itself to modify this rate. PMID:28740463

  12. Characterization of calcium responses and electrical activity in differentiating mouse neural progenitor cells in vitro.

    Science.gov (United States)

    de Groot, Martje W G D M; Dingemans, Milou M L; Rus, Katinka H; de Groot, Aart; Westerink, Remco H S

    2014-02-01

    In vitro methods for developmental neurotoxicity (DNT) testing have the potential to reduce animal use and increase insight into cellular and molecular mechanisms underlying chemical-induced alterations in the development of functional neuronal networks. Mouse neural progenitor cells (mNPCs) differentiate into nervous system-specific cell types and have proven valuable to detect DNT using biochemical and morphological techniques. We therefore investigated a number of functional neuronal parameters in primary mNPCs to explore their applicability for neurophysiological in vitro DNT testing. Immunocytochemistry confirmed that mNPCs express neuronal, glial, and progenitor markers at various differentiation durations (1, 7, 14, and 21 days). Because intracellular calcium ([Ca(2+)]i) plays an essential role in neuronal development and function, we measured stimulus-evoked changes in [Ca(2+)]i at these differentiation durations using the Ca(2+)-responsive dye Fura-2. Increases in [Ca(2+)]i (averages ranging from 65 to 226 nM) were evoked by depolarization, ATP, l-glutamic acid, acetylcholine, and dopamine (up to 87%, 57%, 93%, 28%, and 37% responding cells, respectively) and to a lesser extent by serotonin and gamma-aminobutyric acid (both up to 10% responding cells). Notably, the changes in percentage of responsive cells and their response amplitudes over time indicate changes in the expression and functionality of the respective neurotransmitter receptors and related calcium signaling pathways during in vitro differentiation. The development of functional intercellular signaling pathways was confirmed using multielectrode arrays, demonstrating that mNPCs develop electrical activity within 1-2 weeks of differentiation (55% active wells at 14 days of differentiation; mean spike rate of 1.16 spikes/s/electrode). The combined data demonstrate that mNPCs develop functional neuronal characteristics in vitro, making it a promising model to study chemical-induced effects on the

  13. Molecular Memory of Morphologies by Septins during Neuron Generation Allows Early Polarity Inheritance.

    Science.gov (United States)

    Boubakar, Leila; Falk, Julien; Ducuing, Hugo; Thoinet, Karine; Reynaud, Florie; Derrington, Edmund; Castellani, Valérie

    2017-08-16

    Transmission of polarity established early during cell lineage history is emerging as a key process guiding cell differentiation. Highly polarized neurons provide a fascinating model to study inheritance of polarity over cell generations and across morphological transitions. Neural crest cells (NCCs) migrate to the dorsal root ganglia to generate neurons directly or after cell divisions in situ. Using live imaging of vertebrate embryo slices, we found that bipolar NCC progenitors lose their polarity, retracting their processes to round for division, but generate neurons with bipolar morphology by emitting processes from the same locations as the progenitor. Monitoring the dynamics of Septins, which play key roles in yeast polarity, indicates that Septin 7 tags process sites for re-initiation of process growth following mitosis. Interfering with Septins blocks this mechanism. Thus, Septins store polarity features during mitotic rounding so that daughters can reconstitute the initial progenitor polarity. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. YAP regulates neuronal differentiation through Sonic hedgehog signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Yi-Ting; Ding, Jing-Ya [Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan (China); Li, Ming-Yang [Department of Life Science, National Taiwan Normal University, Taipei 116, Taiwan (China); Yeh, Tien-Shun [Department of Anatomy and Cell Biology, National Yang-Ming University, Taipei 112, Taiwan (China); Wang, Tsu-Wei, E-mail: twwang@ntnu.edu.tw [Department of Life Science, National Taiwan Normal University, Taipei 116, Taiwan (China); Yu, Jenn-Yah, E-mail: jyyu@ym.edu.tw [Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei 112, Taiwan (China); Brain Research Center, National Yang-Ming University, Taipei 112, Taiwan (China)

    2012-09-10

    Tight regulation of cell numbers by controlling cell proliferation and apoptosis is important during development. Recently, the Hippo pathway has been shown to regulate tissue growth and organ size in Drosophila. In mammalian cells, it also affects cell proliferation and differentiation in various tissues, including the nervous system. Interplay of several signaling cascades, such as Notch, Wnt, and Sonic Hedgehog (Shh) pathways, control cell proliferation during neuronal differentiation. However, it remains unclear whether the Hippo pathway coordinates with other signaling cascades in regulating neuronal differentiation. Here, we used P19 cells, a mouse embryonic carcinoma cell line, as a model to study roles of YAP, a core component of the Hippo pathway, in neuronal differentiation. P19 cells can be induced to differentiate into neurons by expressing a neural bHLH transcription factor gene Ascl1. Our results showed that YAP promoted cell proliferation and inhibited neuronal differentiation. Expression of Yap activated Shh but not Wnt or Notch signaling activity during neuronal differentiation. Furthermore, expression of Yap increased the expression of Patched homolog 1 (Ptch1), a downstream target of the Shh signaling. Knockdown of Gli2, a transcription factor of the Shh pathway, promoted neuronal differentiation even when Yap was over-expressed. We further demonstrated that over-expression of Yap inhibited neuronal differentiation in primary mouse cortical progenitors and Gli2 knockdown rescued the differentiation defect in Yap over-expressing cells. In conclusion, our study reveals that Shh signaling acts downstream of YAP in regulating neuronal differentiation. -- Highlights: Black-Right-Pointing-Pointer YAP promotes cell proliferation and inhibits neuronal differentiation in P19 cells. Black-Right-Pointing-Pointer YAP promotes Sonic hedgehog signaling activity during neuronal differentiation. Black-Right-Pointing-Pointer Knockdown of Gli2 rescues the Yap

  15. [Mirror neurons].

    Science.gov (United States)

    Rubia Vila, Francisco José

    2011-01-01

    Mirror neurons were recently discovered in frontal brain areas of the monkey. They are activated when the animal makes a specific movement, but also when the animal observes the same movement in another animal. Some of them also respond to the emotional expression of other animals of the same species. These mirror neurons have also been found in humans. They respond to or "reflect" actions of other individuals in the brain and are thought to represent the basis for imitation and empathy and hence the neurobiological substrate for "theory of mind", the potential origin of language and the so-called moral instinct.

  16. Serotonin Promotes Development and Regeneration of Spinal Motor Neurons in Zebrafish

    Directory of Open Access Journals (Sweden)

    Antón Barreiro-Iglesias

    2015-11-01

    Full Text Available In contrast to mammals, zebrafish regenerate spinal motor neurons. During regeneration, developmental signals are re-deployed. Here, we show that, during development, diffuse serotonin promotes spinal motor neuron generation from pMN progenitor cells, leaving interneuron numbers unchanged. Pharmacological manipulations and receptor knockdown indicate that serotonin acts at least in part via 5-HT1A receptors. In adults, serotonin is supplied to the spinal cord mainly (90% by descending axons from the brain. After a spinal lesion, serotonergic axons degenerate caudal to the lesion but sprout rostral to it. Toxin-mediated ablation of serotonergic axons also rostral to the lesion impaired regeneration of motor neurons only there. Conversely, intraperitoneal serotonin injections doubled numbers of new motor neurons and proliferating pMN-like progenitors caudal to the lesion. Regeneration of spinal-intrinsic serotonergic interneurons was unaltered by these manipulations. Hence, serotonin selectively promotes the development and adult regeneration of motor neurons in zebrafish.

  17. Serotonin Promotes Development and Regeneration of Spinal Motor Neurons in Zebrafish.

    Science.gov (United States)

    Barreiro-Iglesias, Antón; Mysiak, Karolina S; Scott, Angela L; Reimer, Michell M; Yang, Yujie; Becker, Catherina G; Becker, Thomas

    2015-11-01

    In contrast to mammals, zebrafish regenerate spinal motor neurons. During regeneration, developmental signals are re-deployed. Here, we show that, during development, diffuse serotonin promotes spinal motor neuron generation from pMN progenitor cells, leaving interneuron numbers unchanged. Pharmacological manipulations and receptor knockdown indicate that serotonin acts at least in part via 5-HT1A receptors. In adults, serotonin is supplied to the spinal cord mainly (90%) by descending axons from the brain. After a spinal lesion, serotonergic axons degenerate caudal to the lesion but sprout rostral to it. Toxin-mediated ablation of serotonergic axons also rostral to the lesion impaired regeneration of motor neurons only there. Conversely, intraperitoneal serotonin injections doubled numbers of new motor neurons and proliferating pMN-like progenitors caudal to the lesion. Regeneration of spinal-intrinsic serotonergic interneurons was unaltered by these manipulations. Hence, serotonin selectively promotes the development and adult regeneration of motor neurons in zebrafish.

  18. Low Density Lipoprotein Receptor Related Proteins as Regulators of Neural Stem and Progenitor Cell Function

    Directory of Open Access Journals (Sweden)

    Loic Auderset

    2016-01-01

    Full Text Available The central nervous system (CNS is a highly organised structure. Many signalling systems work in concert to ensure that neural stem cells are appropriately directed to generate progenitor cells, which in turn mature into functional cell types including projection neurons, interneurons, astrocytes, and oligodendrocytes. Herein we explore the role of the low density lipoprotein (LDL receptor family, in particular family members LRP1 and LRP2, in regulating the behaviour of neural stem and progenitor cells during development and adulthood. The ability of LRP1 and LRP2 to bind a diverse and extensive range of ligands, regulate ligand endocytosis, recruit nonreceptor tyrosine kinases for direct signal transduction and signal in conjunction with other receptors, enables them to modulate many crucial neural cell functions.

  19. A Bio-Acoustic Levitational (BAL) Assembly Method for Engineering of Multilayered, 3D Brain-Like Constructs, Using Human Embryonic Stem Cell Derived Neuro-Progenitors.

    Science.gov (United States)

    Bouyer, Charlène; Chen, Pu; Güven, Sinan; Demirtaş, Tuğrul Tolga; Nieland, Thomas J F; Padilla, Frédéric; Demirci, Utkan

    2016-01-06

    A bio-acoustic levitational assembly method for engineering of multilayered, 3D brainlike constructs is presented. Acoustic radiation forces are used to levitate neuroprogenitors derived from human embryonic stem cells in 3D multilayered fibrin tissue constructs. The neuro-progenitor cells are subsequently differentiated in neural cells, resulting in a 3D neuronal construct with inter and intralayer neurite elongations.

  20. Isolation of neural progenitor cells from the human adult subventricular zone based on expression of the cell surface marker CD271

    NARCIS (Netherlands)

    van Strien, Miriam E; Sluijs, Jacqueline A; Reynolds, Brent A; Steindler, Dennis A; Aronica, Eleonora; Hol, Elly M

    2014-01-01

    Neural progenitor cells (NPCs) in the subventricular zone (SVZ) hold promise for future therapy for neurodegenerative disorders, because the stimulation of adult neurogenesis could potentially restore the function of degenerating neurons and glia. To obtain more knowledge on these NPCs, we developed

  1. p600 regulates spindle orientation in apical neural progenitors and contributes to neurogenesis in the developing neocortex

    Directory of Open Access Journals (Sweden)

    Camille Belzil

    2014-05-01

    Full Text Available Apical neural progenitors (aNPs drive neurogenesis by means of a program consisting of self-proliferative and neurogenic divisions. The balance between these two manners of division sustains the pool of apical progenitors into late neurogenesis, thereby ensuring their availability to populate the brain with terminal cell types. Using knockout and in utero electroporation mouse models, we report a key role for the microtubule-associated protein 600 (p600 in the regulation of spindle orientation in aNPs, a cellular event that has been associated with cell fate and neurogenesis. We find that p600 interacts directly with the neurogenic protein Ndel1 and that aNPs knockout for p600, depleted of p600 by shRNA or expressing a Ndel1-binding p600 fragment all display randomized spindle orientation. Depletion of p600 by shRNA or expression of the Ndel1-binding p600 fragment also results in a decreased number of Pax6-positive aNPs and an increased number of Tbr2-positive basal progenitors destined to become neurons. These Pax6-positive aNPs display a tilted mitotic spindle. In mice wherein p600 is ablated in progenitors, the production of neurons is significantly impaired and this defect is associated with microcephaly. We propose a working model in which p600 controls spindle orientation in aNPs and discuss its implication for neurogenesis.

  2. Pulse labeling and long-term tracing of newborn neurons in the adult subgranular zone

    Institute of Scientific and Technical Information of China (English)

    Xuewen Cheng; Yang Li; Ying Huang; Xiaoyan Feng; Guoping Feng; Zhi-Qi Xiong

    2011-01-01

    Research over the past decades has demonstrated that adult brain produces neural progenitor cells which proliferate and differentiate to newborn neurons that integrate into the existing circuit.However, detailed differentiation processes and underlying mechanisms of newly generated neurons are largely unknown due to the limitation of available methods for labeling and manipulating neural progenitor cells and newborn neurons. In this study, we designed a tightly controlled,noninvasive system based on Cre/loxP recombination to achieve long-term tracing and genetic manipulation of adult neurons in vivo. In this system, tamoxifen-inducible recomumase,CreERT2,was driven by BAC-based promoter of doublecortin(DCX,a marker of newborn neurons).By crossing this Cre line with reporter mouse, we found that newborn neurons in the dentate gyrus (DG) could be selectively pulse-labeled by tamoxifeninduced expression of yellow fluorescent protein(YFP).YFP-positive neurons were identified by coimmunostaining with cell type-specific markers and characterized by electrophysiological recording.Furthermore,analysis of the migration of these neurons showed that the majority of these labeled neurons migrated to the inner part of granule cell layer.Moreover,spine growth of inner molecular layer of newborn granule neurons takes a dynamic pattern of invert U-shape,in contrast to the wedge-shaped change in the outer molecular layer.Our transgenic tool provides an efficient way to selectively label and manipulate newborn neuron in adult mouse DG.

  3. Endothelial progenitor cells in cardiovascular diseases

    Institute of Scientific and Technical Information of China (English)

    Poay; Sian; Sabrina; Lee; Kian; Keong; Poh

    2014-01-01

    Endothelial dysfunction has been associated with the development of atherosclerosis and cardiovascular diseases. Adult endothelial progenitor cells(EPCs) are derived from hematopoietic stem cells and are capable of forming new blood vessels through a process of vas-culogenesis. There are studies which report correlations between circulating EPCs and cardiovascular risk fac-tors. There are also studies on how pharmacotherapies may influence levels of circulating EPCs. In this review, we discuss the potential role of endothelial progenitor cells as both diagnostic and prognostic biomarkers. In addition, we look at the interaction between cardio-vascular pharmacotherapies and endothelial progenitor cells. We also discuss how EPCs can be used directly and indirectly as a therapeutic agent. Finally, we evalu-ate the challenges facing EPC research and how these may be overcome.

  4. Endogenous and exogenous CNS derived stem/progenitor cell approaches for neurotrauma.

    Science.gov (United States)

    Kulbatski, I; Mothe, A J; Nomura, H; Tator, C H

    2005-02-01

    Neural stem/progenitor cells capable of generating new neurons and glia, reside in specific areas of the adult mammalian central nervous system (CNS), including the ependymal region of the spinal cord and the subventricular zone (SVZ), hippocampus, and dentate gyrus of the brain. Much is known about the neurogenic regions in the CNS, and their response to various stimuli including injury, neurotrophins (NFs), morphogens, and environmental factors like learning, stress, and aging. This work has shaped our current views about the CNS's potential to recover lost tissue and function post-traumatically and the therapies to support the intrinsic regenerative capacity of the brain or spinal cord. Recently, intensive research has explored the potential of harvesting, culturing, and transplanting neural stem/progenitors as a therapeutic intervention for spinal cord injury (SCI) and traumatic brain injury (TBI). Another strategy has focused on maximizing the potential of this endogenous population of cells by stimulating their recruitment, proliferation, migration, and differentiation in vivo following traumatic lesions to the CNS. The promise of such experimental treatments has prompted tissue and biomaterial engineers to implant synthetic three-dimensional biodegradable scaffolds seeded with neural stem/progenitors into CNS lesions. Although there is no definitive answer about the ideal cell type for transplantation, strong evidence supports the use of region specific neural stem/progenitors. The technical and logistic considerations for transplanting neural stem/progenitors are extensive and crucial to optimizing and maintaining cell survival both before and after transplantation, as well as for tracking the fate of transplanted cells. These issues have been systematically addressed in many animal models, that has improved our understanding and approach to clinical therapeutic paradigms.

  5. Human neural progenitors express functional lysophospholipid receptors that regulate cell growth and morphology

    Directory of Open Access Journals (Sweden)

    Callihan Phillip

    2008-12-01

    Full Text Available Abstract Background Lysophospholipids regulate the morphology and growth of neurons, neural cell lines, and neural progenitors. A stable human neural progenitor cell line is not currently available in which to study the role of lysophospholipids in human neural development. We recently established a stable, adherent human embryonic stem cell-derived neuroepithelial (hES-NEP cell line which recapitulates morphological and phenotypic features of neural progenitor cells isolated from fetal tissue. The goal of this study was to determine if hES-NEP cells express functional lysophospholipid receptors, and if activation of these receptors mediates cellular responses critical for neural development. Results Our results demonstrate that Lysophosphatidic Acid (LPA and Sphingosine-1-phosphate (S1P receptors are functionally expressed in hES-NEP cells and are coupled to multiple cellular signaling pathways. We have shown that transcript levels for S1P1 receptor increased significantly in the transition from embryonic stem cell to hES-NEP. hES-NEP cells express LPA and S1P receptors coupled to Gi/o G-proteins that inhibit adenylyl cyclase and to Gq-like phospholipase C activity. LPA and S1P also induce p44/42 ERK MAP kinase phosphorylation in these cells and stimulate cell proliferation via Gi/o coupled receptors in an Epidermal Growth Factor Receptor (EGFR- and ERK-dependent pathway. In contrast, LPA and S1P stimulate transient cell rounding and aggregation that is independent of EGFR and ERK, but dependent on the Rho effector p160 ROCK. Conclusion Thus, lysophospholipids regulate neural progenitor growth and morphology through distinct mechanisms. These findings establish human ES cell-derived NEP cells as a model system for studying the role of lysophospholipids in neural progenitors.

  6. Cortical excitatory neurons become protected from cell division during neurogenesis in an Rb family-dependent manner.

    Science.gov (United States)

    Oshikawa, Mio; Okada, Kei; Nakajima, Kazunori; Ajioka, Itsuki

    2013-06-01

    Cell cycle dysregulation leads to abnormal proliferation and cell death in a context-specific manner. Cell cycle progression driven via the Rb pathway forces neurons to undergo S-phase, resulting in cell death associated with the progression of neuronal degeneration. Nevertheless, some Rb- and Rb family (Rb, p107 and p130)-deficient differentiating neurons can proliferate and form tumors. Here, we found in mouse that differentiating cerebral cortical excitatory neurons underwent S-phase progression but not cell division after acute Rb family inactivation in differentiating neurons. However, the differentiating neurons underwent cell division and proliferated when Rb family members were inactivated in cortical progenitors. Differentiating neurons generated from Rb(-/-); p107(-/-); p130(-/-) (Rb-TKO) progenitors, but not acutely inactivated Rb-TKO differentiating neurons, activated the DNA double-strand break (DSB) repair pathway without increasing trimethylation at lysine 20 of histone H4 (H4K20), which has a role in protection against DNA damage. The activation of the DSB repair pathway was essential for the cell division of Rb-TKO differentiating neurons. These results suggest that newly born cortical neurons from progenitors become epigenetically protected from DNA damage and cell division in an Rb family-dependent manner.

  7. Core-Collapse supernovae and its progenitors

    CERN Document Server

    Bose, Subhash; Misra, Kuntal

    2016-01-01

    Massive stars unable to sustain gravitational collapse, at the end of nuclear burning stage, turns out into core-collapse supernovae, leaving behind compact objects like neutron stars or black holes. The progenitor properties like mass and metallicity primarily governs the explosion parameters and type of compact remnant. In this contribution we summarize observational study of three Core Collapse type IIP SNe 2012aw, 2013ab and 2013ej, which are rigorously observed from ARIES and other Indian observatories and discuss their progenitor and explosion properties.

  8. X Inactivation and Progenitor Cancer Cells

    Directory of Open Access Journals (Sweden)

    Ruben Agrelo

    2011-04-01

    Full Text Available In mammals, silencing of one of the two X chromosomes is necessary to achieve dosage compensation. The 17 kb non-coding RNA called Xist triggers X inactivation. Gene silencing by Xist can only be achieved in certain contexts such as in cells of the early embryo and in certain hematopoietic progenitors where silencing factors are present. Moreover, these epigenetic contexts are maintained in cancer progenitors in which SATB1 has been identified as a factor related to Xist-mediated chromosome silencing.

  9. Immune-mediated bone marrow failure syndromes of progenitor and stem cells: molecular analysis of cytotoxic T cell clones.

    Directory of Open Access Journals (Sweden)

    Ramon Tiu

    2007-03-01

    Full Text Available The unique structure of the T cell receptor (TCR enables molecular identification of individual T cell clones and provides an unique opportunity for the design of molecular diagnostic tests based on the structure of the rearranged TCR chain e.g., using the TCR CDR3 region. Initially, clonal T cell malignancies, including T cell large granular lymphocyte leukemia (T-LGL, mucosis fungoides and peripheral T cell lymphoma were targets for the TCR-based analytic assays such as detection of clonality by T-gamma rearrangement using y-chain-specific PCR or Southern Blotting. Study of these disorders facilitated further analytic concepts and application of rational methods of TCR analysis to investigations of polyclonal T cell-mediated diseases. In hematology, such conditions include graft versus host disease (GvHD and immune-mediated bone marrow failure syndromes. In aplastic anemia (AA, myelodysplastic syndrome (MDS or paroxysmal nocturnal hemoglobinuria (PNH, cytotoxic T cell responses may be directed against certain antigens located on stem or more lineage-restricted progenitor cells in single lineage cytopenias. The nature of the antigenic targets driving polyclonal CTL responses remains unclear. Novel methods of TCR repertoire analysis, include VB flow cytometry, peptide-specific tetramer staining, in vitro stimulation assays and TCR CDR3-specific PCR. Such PCR assay can be either VB family-specific or multiplexed for all VB families. Amplified products can be characterized and quantitated to facilitate detection of the most immunodominant clonotypes. Such clonotypes may serve as markers for the global polyclonal T cell response. Identification of these clonotypes can be performed in blood and tissue biopsy material by various methods. Once immunodominant clonotypes corresponding to pathogenic CTL clones are identified they can serve as surrogate markers for the activity of the pathophysiologic process or even indicate the presence of specific

  10. Siah regulation of Pard3A controls neuronal cell adhesion during germinal zone exit.

    Science.gov (United States)

    Famulski, Jakub K; Trivedi, Niraj; Howell, Danielle; Yang, Yuan; Tong, Yiai; Gilbertson, Richard; Solecki, David J

    2010-12-24

    The brain's circuitry is established by directed migration and synaptogenesis of neurons during development. Although neurons mature and migrate in specific patterns, little is known about how neurons exit their germinal zone niche. We found that cerebellar granule neuron germinal zone exit is regulated by proteasomal degradation of Pard3A by the Seven in Absentia homolog (Siah) E3 ubiquitin ligase. Pard3A gain of function and Siah loss of function induce precocious radial migration. Time-lapse imaging using a probe to measure neuronal cell contact reveals that Pard3A promotes adhesive interactions needed for germinal zone exit by recruiting the epithelial tight junction adhesion molecule C to the neuronal cell surface. Our findings define a Siah-Pard3A signaling pathway that controls adhesion-dependent exit of neuronal progenitors or immature neurons from a germinal zone niche.

  11. Proliferative hypothalamic neurospheres express NPY, AGRP, POMC, CART and Orexin-A and differentiate to functional neurons.

    Directory of Open Access Journals (Sweden)

    Lígia Sousa-Ferreira

    Full Text Available Some pathological conditions with feeding pattern alterations, including obesity and Huntington disease (HD are associated with hypothalamic dysfunction and neuronal cell death. Additionally, the hypothalamus is a neurogenic region with the constitutive capacity to generate new cells of neuronal lineage, in adult rodents. The aim of the present work was to evaluate the expression of feeding-related neuropeptides in hypothalamic progenitor cells and their capacity to differentiate to functional neurons which have been described to be affected by hypothalamic dysfunction. Our study shows that hypothalamic progenitor cells from rat embryos grow as floating neurospheres and express the feeding-related neuropeptides Neuropeptide Y (NPY, Agouti-related Protein (AGRP, Pro-OpioMelanocortin (POMC, Cocaine-and-Amphetamine Responsive Transcript (CART and Orexin-A/Hypocretin-1. Moreover the relative mRNA expression of NPY and POMC increases during the expansion of hypothalamic neurospheres in proliferative conditions.Mature neurons were obtained from the differentiation of hypothalamic progenitor cells including NPY, AGRP, POMC, CART and Orexin-A positive neurons. Furthermore the relative mRNA expression of NPY, CART and Orexin-A increases after the differentiation of hypothalamic neurospheres. Similarly to the adult hypothalamic neurons the neurospheres-derived neurons express the glutamate transporter EAAT3. The orexigenic and anorexigenic phenotype of these neurons was identified by functional response to ghrelin and leptin hormones, respectively. This work demonstrates the presence of appetite-related neuropeptides in hypothalamic progenitor cells and neurons obtained from the differentiation of hypothalamic neurospheres, including the neuronal phenotypes that have been described by others as being affected by hypothalamic neurodegeneration. These in vitro models can be used to study hypothalamic progenitor cells aiming a therapeutic intervention to

  12. Cross-talk between the epidermal growth factor-like repeats/fibronectin 6-8 repeats domains of Tenascin-R and microglia modulates neural stem/progenitor cell proliferation and differentiation.

    Science.gov (United States)

    Liao, Hong; Huang, Wenhui; Niu, Rui; Sun, Lixin; Zhang, Luyong

    2008-01-01

    Mounting evidence has demonstrated that the microenvironment of stem/progenitor cells plays an important role in their proliferation and commitment to their fate. However, it remains unclear how all elements, such as astrocytes, microglia, extracellular matrix molecules, soluble factors, and their cross-talk interactions in the microenvironments, affect neural stem/progenitor cell fate. This work explored the influences of cross-talk between Tenascin-R (TN-R) and microglia on neural stem/progenitor cell proliferation and differentiation. Our results show that microglia triggered by TN-R distinct domains EGF-like repeats (EGFL) and fibronectin 6-8 repeats (FN6-8) significantly enhanced the proliferation of neural stem/progenitor cells and also obviously induced the differentiation into neurons but not oligodendrocytes. Neurite processes of neurons generated from neural progenitor cells were promoted by both EGFL and FN6-8 domains-activated microglia. Microglia triggered by EGFL and FN6-8 secreted brain-derived neurotrophic factor (BDNF) and transforming growth factor-beta (TGF-beta); interestingly, FN6-8 could activate microglia to secrete nerve growth factor in addition to BDNF and TGF-beta, but EGFL domain could not. All these data implied that the cross-talk between TN-R distinct domains EGFL/FN6-8 and microglia promoted neural stem/progenitor cell proliferation and induced their differentiation into neurons.

  13. Agmatine increases proliferation of cultured hippocampal progenitor cells and hippocampal neurogenesis in chronically stressed mice

    Institute of Scientific and Technical Information of China (English)

    Yun-feng LI; Hong-xia CHEN; Ying LIU; You-zhi ZHANG; Yan-qin LIU; Jin LI

    2006-01-01

    Aim:To explore the mechanism of agmatine's antidepressant action.Methods: Male mice were subjected to a variety of unpredictable stressors on a daily basis over a 24-d period.The open-field behaviors of the mice were displayed and recorded using a Videomex-V image analytic system automatically.For bromodeoxyuridine (BrdU;thymidine analog as a marker for dividing cells) labeling,the mice were injected with BrdU (100 mg/kg,ip,twice per d for 2 d),and the hippocampal neurogenesis in stressed mice was measured by immunohistochemistry.The proliferation of cultured hippocampal progenitor cells from neonatal rats was determined by colorimetric assay (cell counting kit-8) and 3H-thymidine incorporation assay.Results:After the onset of chronic stress,the locomotor activity of the mice in the open field significantly decreased,while coadministration of agmatine 10 mg/kg (po) blocked it.Furthermore,the number of BrdU-labeled cells in the hippocampal dentate gyrus significantly decreased in chronically stressed mice, which was also blocked by chronic coadministration with agmatine 10 mg/kg (po). Four weeks after the BrdU injection, some of the new born cells matured and became neurons, as determined by double labeling for BrdU and neuron specific enolase (NSE), a marker for mature neurons.In vitro treatment with agmatine 0.1-10 μmo1/L for 3 d significantly increased the proliferation of the cultured hippocampal progenitor cells in a dose-dependent manner.Conclusion:We have found that agmatine increases proliferation of hippocampal progenitor cells in vitro and the hippocampal neurogenesis in vivo in chronically stressed mice.This may be one of the important mechanisms involved in agmatine's antidepressant action.

  14. An interneuron progenitor maintains neurogenic potential in vivo and differentiates into GABAergic interneurons after transplantation in the postnatal rat brain.

    Science.gov (United States)

    Wang, Qi; Hong, Peiwei; Gao, Hui; Chen, Yuntian; Yang, Qi; Jiang, Mei; Li, Hedong

    2016-01-11

    Dysfunction of cortical GABAergic interneurons are involved in numerous neurological disorders including epilepsy, schizophrenia and autism; and replenishment of these cells by transplantation strategy has proven to be a feasible and effective method to help revert the symptoms in several animal models. To develop methodology of generating transplantable GABAergic interneurons for therapy, we previously reported the isolation of a v-myc-induced GABAergic interneuron progenitor clone GE6 from embryonic ganglionic eminence (GE). These cells can proliferate and form functional inhibitory synapses in culture. Here, we tested their differentiation behavior in vivo by transplanting them into the postnatal rat forebrain. We found that GE6 cells migrate extensively in the neonatal forebrain and differentiate into both neurons and glia, but preferentially into neurons when compared with a sister progenitor clone CTX8. The neurogenic potential of GE6 cells is also maintained after transplantation into a non-permissive environment such as adult cortex or when treated with inflammatory cytokine in culture. The GE6-derived neurons were able to mature in vivo as GABAergic interneurons expressing GABAergic, not glutamatergic, presynaptic puncta. Finally, we propose that v-myc-induced human interneuron progenitor clones could be an alternative cell source of transplantable GABAergic interneurons for treating related neurological diseases in future clinic.

  15. ESC-Derived BDNF-Overexpressing Neural Progenitors Differentially Promote Recovery in Huntington's Disease Models by Enhanced Striatal Differentiation

    Directory of Open Access Journals (Sweden)

    Tina Zimmermann

    2016-10-01

    Full Text Available Huntington's disease (HD is characterized by fatal motoric failures induced by loss of striatal medium spiny neurons. Neuronal cell death has been linked to impaired expression and axonal transport of the neurotrophin BDNF (brain-derived neurotrophic factor. By transplanting embryonic stem cell-derived neural progenitors overexpressing BDNF, we combined cell replacement and BDNF supply as a potential HD therapy approach. Transplantation of purified neural progenitors was analyzed in a quinolinic acid (QA chemical and two genetic HD mouse models (R6/2 and N171-82Q on the basis of distinct behavioral parameters, including CatWalk gait analysis. Explicit rescue of motor function by BDNF neural progenitors was found in QA-lesioned mice, whereas genetic mouse models displayed only minor improvements. Tumor formation was absent, and regeneration was attributed to enhanced neuronal and striatal differentiation. In addition, adult neurogenesis was preserved in a BDNF-dependent manner. Our findings provide significant insight for establishing therapeutic strategies for HD to ameliorate neurodegenerative symptoms.

  16. Motor Neurons

    DEFF Research Database (Denmark)

    Hounsgaard, Jorn

    2017-01-01

    Motor neurons translate synaptic input from widely distributed premotor networks into patterns of action potentials that orchestrate motor unit force and motor behavior. Intercalated between the CNS and muscles, motor neurons add to and adjust the final motor command. The identity and functional...... properties of this facility in the path from synaptic sites to the motor axon is reviewed with emphasis on voltage sensitive ion channels and regulatory metabotropic transmitter pathways. The catalog of the intrinsic response properties, their underlying mechanisms, and regulation obtained from motoneurons...... in in vitro preparations is far from complete. Nevertheless, a foundation has been provided for pursuing functional significance of intrinsic response properties in motoneurons in vivo during motor behavior at levels from molecules to systems....

  17. Characterization of hepatic progenitors from human fetal liver using CD34 as a hepatic progenitor marker

    Institute of Scientific and Technical Information of China (English)

    Parveen Nyamath; Ayesha AM; Aejaz Habeeb; Sanjeev Khosla; Aleem A Khan; CM Habibullah

    2007-01-01

    AIM: To enrich putative hepatic progenitors from the developing human fetal liver using CD34 as a marker.METHODS: Aborted fetuses of 13-20 wk were used for the isolation of liver cells. The cells were labeled with anti CD34; a marker used for isolating progenitor population and the cells were sorted using magnetic cell sorting. The positive fractions of cells were assessed for specific hepatic markers. Further, these cells were cultured in vitro for long term investigation.RESULTS: Flow cytometric and immunocytochemical analysis for alphafetoprotein (AFP) showed that the majority of the enriched CD34 positive cells were positive for AFP. Furthermore, these enriched cells proliferated in the long term and maintained hepatic characteristics in in vitro culture.CONCLUSION: The study shows that aborted human fetal liver is a potential source for isolation of hepatic progenitors for clinical applications. The study also demonstrates that CD34 can be a good marker for the enrichment of progenitor populations.

  18. Single Degenerate Progenitors of Type Ia Supernovae

    Science.gov (United States)

    Bours, Madelon; Toonen, Silvia; Nelemans, Gijs

    2013-01-01

    There is a general agreement that Type Ia supernovae correspond to the thermonuclear runaway of a white dwarf (WD) in a compact binary. The details of these progenitor systems are still unclear. Using the population synthesis code SeBa and several assumption for the WD retention efficiency, we estimate the delay times and supernova rates for the single degenerate scenario.

  19. Direct Conversion of Fibroblasts to Megakaryocyte Progenitors

    Directory of Open Access Journals (Sweden)

    Julian Pulecio

    2016-10-01

    Full Text Available Current sources of platelets for transfusion are insufficient and associated with risk of alloimmunization and blood-borne infection. These limitations could be addressed by the generation of autologous megakaryocytes (MKs derived in vitro from somatic cells with the ability to engraft and differentiate in vivo. Here, we show that overexpression of a defined set of six transcription factors efficiently converts mouse and human fibroblasts into MK-like progenitors. The transdifferentiated cells are CD41+, display polylobulated nuclei, have ploidies higher than 4N, form MK colonies, and give rise to platelets in vitro. Moreover, transplantation of MK-like murine progenitor cells into NSG mice results in successful engraftment and further maturation in vivo. Similar results are obtained using disease-corrected fibroblasts from Fanconi anemia patients. Our results combined demonstrate that functional MK progenitors with clinical potential can be obtained in vitro, circumventing the use of hematopoietic progenitors or pluripotent stem cells.

  20. Targeting human oligodendrocyte progenitors for myelin repair.

    Science.gov (United States)

    Dietz, Karen C; Polanco, Jessie J; Pol, Suyog U; Sim, Fraser J

    2016-09-01

    Oligodendrocyte development has been studied for several decades, and has served as a model system for both neurodevelopmental and stem/progenitor cell biology. Until recently, the vast majority of studies have been conducted in lower species, especially those focused on rodent development and remyelination. In humans, the process of myelination requires the generation of vastly more myelinating glia, occurring over a period of years rather than weeks. Furthermore, as evidenced by the presence of chronic demyelination in a variety of human neurologic diseases, it appears likely that the mechanisms that regulate development and become dysfunctional in disease may be, in key ways, divergent across species. Improvements in isolation techniques, applied to primary human neural and oligodendrocyte progenitors from both fetal and adult brain, as well as advancements in the derivation of defined progenitors from human pluripotent stem cells, have begun to reveal the extent of both species-conserved signaling pathways and potential key differences at cellular and molecular levels. In this article, we will review the commonalities and differences in myelin development between rodents and man, describing the approaches used to study human oligodendrocyte differentiation and myelination, as well as heterogeneity within targetable progenitor pools, and discuss the advances made in determining which conserved pathways may be both modeled in rodents and translate into viable therapeutic strategies to promote myelin repair.

  1. SUPERNOVA REMNANT PROGENITOR MASSES IN M31

    Energy Technology Data Exchange (ETDEWEB)

    Jennings, Zachary G.; Williams, Benjamin F.; Dalcanton, Julianne J.; Gilbert, Karoline M.; Fouesneau, Morgan; Weisz, Daniel R. [Department of Astronomy, University of Washington Seattle, Box 351580, WA 98195 (United States); Murphy, Jeremiah W. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Dolphin, Andrew E., E-mail: zachjenn@uw.edu, E-mail: adolphin@raytheon.com [Raytheon, 1151 East Hermans Road, Tucson, AZ 85706 (United States)

    2012-12-10

    Using Hubble Space Telescope photometry, we age-date 59 supernova remnants (SNRs) in the spiral galaxy M31 and use these ages to estimate zero-age main-sequence masses (M{sub ZAMS}) for their progenitors. To accomplish this, we create color-magnitude diagrams (CMDs) and employ CMD fitting to measure the recent star formation history of the regions surrounding cataloged SNR sites. We identify any young coeval population that likely produced the progenitor star, then assign an age and uncertainty to that population. Application of stellar evolution models allows us to infer the M{sub ZAMS} from this age. Because our technique is not contingent on identification or precise location of the progenitor star, it can be applied to the location of any known SNRs. We identify significant young star formation around 53 of the 59 SNRs and assign progenitor masses to these, representing a factor of {approx}2 increase over currently measured progenitor masses. We consider the remaining six SNRs as either probable Type Ia candidates or the result of core-collapse progenitors that have escaped their birth sites. In general, the distribution of recovered progenitor masses is bottom-heavy, showing a paucity of the most massive stars. If we assume a single power-law distribution, dN/dM{proportional_to}M{sup {alpha}}, then we find a distribution that is steeper than a Salpeter initial mass function (IMF) ({alpha} = -2.35). In particular, we find values of {alpha} outside the range -2.7 {>=} {alpha} {>=} -4.4 to be inconsistent with our measured distribution at 95% confidence. If instead we assume a distribution that follows a Salpeter IMF up to some maximum mass, then we find that values of M{sub Max} > 26 are inconsistent with the measured distribution at 95% confidence. In either scenario, the data suggest that some fraction of massive stars may not explode. The result is preliminary and requires more SNRs and further analysis. In addition, we use our distribution to estimate a

  2. Duration of Shh signaling contributes to mDA neuron diversity.

    Science.gov (United States)

    Hayes, Lindsay; Ralls, Sherry; Wang, Hui; Ahn, Sohyun

    2013-02-01

    Sonic hedgehog (Shh) signaling is critical for various developmental processes including specification of the midbrain dopamine (mDA) neurons in the ventral mesencephalon (vMes). While the timing of Shh and its response gene Gli1 segregates mDA neurons, their overall lineage contribution to mDA neurons heavily overlaps. Here, we demonstrate that the same set of mDA neuron progenitors sequentially respond to Shh signaling (Gli1 expression), induce Shh expression, and then turn off Shh responsiveness. Thus, at any given developmental stage, cells rarely co-express Shh and Gli1. Using Shh(Cre:GFP) mice to delete the Smoothened receptor in the Shh pathway, we demonstrate that the loss of Shh signaling in Shh expressing cells results in a transient increase in proliferation and subsequent depletion of mDA neuron progenitors in the posterior vMes due to the facilitated cell cycle exit. Moreover, the change in duration of Shh signaling in vMes progenitors altered the timing of the contribution to the ventral tegmental area (VTA) and the substantia nigra pars compacta (SNc) mDA neurons. Taken together, our investigation on the relationship between the Shh-secreting and -responding cells revealed an intricate regulation of induction and cessation of Shh signaling that influences the distribution of mDA neurons in the VTA and SNc.

  3. Characterization of Hemagglutinin Negative Botulinum Progenitor Toxins

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    Suzanne R. Kalb

    2017-06-01

    Full Text Available Botulism is a disease involving intoxication with botulinum neurotoxins (BoNTs, toxic proteins produced by Clostridium botulinum and other clostridia. The 150 kDa neurotoxin is produced in conjunction with other proteins to form the botulinum progenitor toxin complex (PTC, alternating in size from 300 kDa to 500 kDa. These progenitor complexes can be classified into hemagglutinin positive or hemagglutinin negative, depending on the ability of some of the neurotoxin-associated proteins (NAPs to cause hemagglutination. The hemagglutinin positive progenitor toxin complex consists of BoNT, nontoxic non-hemagglutinin (NTNH, and three hemagglutinin proteins; HA-70, HA-33, and HA-17. Hemagglutinin negative progenitor toxin complexes contain BoNT and NTNH as the minimally functional PTC (M-PTC, but not the three hemagglutinin proteins. Interestingly, the genome of hemagglutinin negative progenitor toxin complexes comprises open reading frames (orfs which encode for three proteins, but the existence of these proteins has not yet been extensively demonstrated. In this work, we demonstrate that these three proteins exist and form part of the PTC for hemagglutinin negative complexes. Several hemagglutinin negative strains producing BoNT/A, /E, and /F were found to contain the three open reading frame proteins. Additionally, several BoNT/A-containing bivalent strains were examined, and NAPs from both genes, including the open reading frame proteins, were associated with BoNT/A. The open reading frame encoded proteins are more easily removed from the botulinum complex than the hemagglutinin proteins, but are present in several BoNT/A and /F toxin preparations. These are not easily removed from the BoNT/E complex, however, and are present even in commercially-available purified BoNT/E complex.

  4. Duration of Shh signaling contributes to mDA neuron diversity

    OpenAIRE

    Hayes, Lindsay; Ralls, Sherry; Wang, Hui; Ahn, Sohyun

    2012-01-01

    Sonic hedgehog (Shh) signaling is critical for various developmental processes including specification of the midbrain dopamine (mDA) neurons in the ventral mesencephalon (vMes). While the timing of Shh and its response gene Gli1 segregates mDA neurons, their overall lineage contribution to mDA neurons heavily overlaps. Here, we demonstrate that the same set of mDA neuron progenitors sequentially respond to Shh signaling (Gli1 expression), induce Shh expression, and then turn off Shh responsi...

  5. Neuronal Polarity in the Embryonic Mammalian Cerebral Cortex

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    Elif Kon

    2017-06-01

    Full Text Available The cerebral cortex is composed of billions of neurons that can grossly be subdivided into two broad classes: inhibitory GABAergic interneurons and excitatory glutamatergic neurons. The majority of cortical neurons in mammals are the excitatory type and they are the main focus of this review article. Like many of the cells in multicellular organisms, fully differentiated neurons are both morphologically and functionally polarized. However, they go through several changes in polarity before reaching this final mature differentiated state. Neurons are derived from polarized neuronal progenitor/stem cells and their commitment to neuronal fate is decided by cellular and molecular asymmetry during their last division in the neurogenic zone. They migrate from their birthplace using so-called multipolar migration, during which they switch direction of movement several times, and repolarize for bipolar migration when the axon is specified. Therefore, neurons have to break their previous symmetry, change their morphology and adequately respond to polarizing signals during migration in order to reach the correct position in the cortex and start making connections. Finally, the dendritic tree is elaborated and the axon/dendrite morphological polarity is set. Here we will describe the function, establishment and maintenance of polarity during the different developmental steps starting from neural stem cell (NSC division, neuronal migration and axon specification at embryonic developmental stages.

  6. Apoptotic death of olfactory sensory neurons in the adult rat.

    Science.gov (United States)

    Deckner, M L; Risling, M; Frisén, J

    1997-01-01

    Olfactory sensory neurons only live for about 1 month in most mammals. It is not fully understood whether the short life span of these neurons is due to necrotic death, or if these cells die by apoptosis. One characteristic of cells undergoing apoptotic cell death is internucleosomal DNA-fragmentation. We have used TdT-mediated dUTP-digoxigenin nick end labeling (TUNEL) to detect cells undergoing DNA-fragmentation in situ. In the intact olfactory epithelium of adult rats a subpopulation of basal immature neuronal progenitor cells, as well as mature olfactory sensory neurons, showed DNA-fragmentation. The number of TUNEL-labeled neurons increased dramatically 1.5 days after transection of the fila olfactoria and declined to control levels by Day 4 after the injury. In order to relate DNA-fragmentation to ultrastructural characteristics of apoptosis we modified the TUNEL-labeling protocol to enable studies of TUNEL-labeled cells in the electron microscope. This confirmed that TUNEL-labeled neurons showed morphological characteristics of apoptosis. The data provide evidence for apoptotic death of neurons in the adult mammalian nervous system. The turnover of olfactory sensory neurons is, at least in part, regulated by apoptosis and disruption of the contact with the olfactory bulb results in massive apoptotic death of neurons in the olfactory epithelium.

  7. The homeobox gene Gsx2 regulates the self-renewal and differentiation of neural stem cells and the cell fate of postnatal progenitors.

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    Héctor R Méndez-Gómez

    Full Text Available The Genetic screened homeobox 2 (Gsx2 transcription factor is required for the development of olfactory bulb (OB and striatal neurons, and for the regional specification of the embryonic telencephalon. Although Gsx2 is expressed abundantly by progenitor cells in the ventral telencephalon, its precise function in the generation of neurons from neural stem cells (NSCs is not clear. Similarly, the role of Gsx2 in regulating the self-renewal and multipotentiality of NSCs has been little explored. Using retroviral vectors to express Gsx2, we have studied the effect of Gsx2 on the growth of NSCs isolated from the OB and ganglionic eminences (GE, as well as its influence on the proliferation and cell fate of progenitors in the postnatal mouse OB. Expression of Gsx2 reduces proliferation and the self-renewal capacity of NSCs, without significantly affecting cell death. Furthermore, Gsx2 overexpression decreases the differentiation of NSCs into neurons and glia, and it maintains the cells that do not differentiate as cycling progenitors. These effects were stronger in GESCs than in OBSCs, indicating that the actions of Gsx2 are cell-dependent. In vivo, Gsx2 produces a decrease in the number of Pax6+ cells and doublecortin+ neuroblasts, and an increase in Olig2+ cells. In summary, our findings show that Gsx2 inhibits the ability of NSCs to proliferate and self-renew, as well as the capacity of NSC-derived progenitors to differentiate, suggesting that this transcription factor regulates the quiescent and undifferentiated state of NSCs and progenitors. Furthermore, our data indicate that Gsx2 negatively regulates neurogenesis from postnatal progenitor cells.

  8. TGF-β Signaling in Neuronal Stem Cells

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    Chohee Yun

    2008-01-01

    Full Text Available Transforming growth factor beta (TGF-β signaling has diverse and complex roles in various biological phenomena such as cell growth, differentiation, embryogenesis and morphogenesis. ES cells provide an essential model for understanding the role of TGF-β signaling in lineage specification and differentiation. Recent studies have suggested significant role of TGF-β in stem/progenitor cell biology. Here in this review, we focus on the role of the TGF-β superfamily in neuronal development.

  9. The influence of immunosuppressive drugs on neural stem/progenitor cell fate in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Skardelly, Marco, E-mail: Marco.Skardelly@med.uni-tuebingen.de [Department of Neurosurgery, University Hospital, Leipzig (Germany); Translational Centre for Regenerative Medicine, University of Leipzig, Leipzig (Germany); Glien, Anja; Groba, Claudia; Schlichting, Nadine [Department of Neurosurgery, University Hospital, Leipzig (Germany); Kamprad, Manja [Institute of Clinical Immunology, Medical Faculty, University of Leipzig, Leipzig (Germany); Meixensberger, Juergen [Department of Neurosurgery, University Hospital, Leipzig (Germany); Milosevic, Javorina [Translational Centre for Regenerative Medicine, University of Leipzig, Leipzig (Germany)

    2013-12-10

    In allogenic and xenogenic transplantation, adequate immunosuppression plays a major role in graft survival, especially over the long term. The effect of immunosuppressive drugs on neural stem/progenitor cell fate has not been sufficiently explored. The focus of this study is to systematically investigate the effects of the following four different immunotherapeutic strategies on human neural progenitor cell survival/death, proliferation, metabolic activity, differentiation and migration in vitro: (1) cyclosporine A (CsA), a calcineurin inhibitor; (2) everolimus (RAD001), an mTOR-inhibitor; (3) mycophenolic acid (MPA, mycophenolate), an inhibitor of inosine monophosphate dehydrogenase and (4) prednisolone, a steroid. At the minimum effective concentration (MEC), we found a prominent decrease in hNPCs' proliferative capacity (BrdU incorporation), especially for CsA and MPA, and an alteration of the NAD(P)H-dependent metabolic activity. Cell death rate, neurogenesis, gliogenesis and cell migration remained mostly unaffected under these conditions for all four immunosuppressants, except for apoptotic cell death, which was significantly increased by MPA treatment. - Highlights: • Four immunosuppresants (ISs) were tested in human neural progenitor cells in vitro. • Cyclosporine A and mycophenolic acid showed a prominent anti-proliferative activity • Mycophenolic acid exhibited a significant pro-apoptotic effect. • NAD(P)H-dependent metabolic activity was occasionally induced by ISs. • Neuronal differentiation and migration potential remained unaffected by ISs treatment.

  10. Generation and In Vitro Expansion of Hepatic Progenitor Cells from Human iPS Cells.

    Science.gov (United States)

    Yanagida, Ayaka; Nakauchi, Hiromitsu; Kamiya, Akihide

    2016-01-01

    Stem cells have the unique properties of self-renewal and multipotency (producing progeny belonging to two or more lineages). Induced pluripotent stem (iPS) cells can be generated from somatic cells by simultaneous expression of pluripotent factors (Oct3/4, Klf4, Sox2, and c-Myc). They share the same properties as embryonic stem (ES) cells and can differentiate into several tissue cells, i.e., neurons, hematopoietic cells, and liver cells. Therefore, iPS cells are suitable candidate cells for regenerative medicine and analyses of disease mechanisms.The liver is the major organ that regulates a multitude of metabolic functions. Hepatocytes are the major cell type populating the liver parenchyma and express several metabolic enzymes that are necessary for liver functions. Although hepatocytes are essential for maintaining homeostasis, it is difficult to alter artificial and transplanted cells because of their multifunctionality, donor shortage, and immunorejection risk. During liver development, hepatic progenitor cells in the fetal liver differentiate into both mature hepatocytes and cholangiocytes. As hepatic progenitor cells have bipotency and high proliferation ability, they could present a potential source for generating transplantable cells or as a liver study model. Here we describe the induction and purification of hepatic progenitor cells derived from human iPS cells. These cells can proliferate for a long term under suitable culture conditions.

  11. Lipidome of midbody released from neural stem and progenitor cells during mammalian cortical neurogenesis

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    Yoko eArai

    2015-08-01

    Full Text Available Midbody release from proliferative neural progenitor cells is tightly associated with the neuronal commitment of neural progenitor cells during the progression of neurogenesis in the mammalian cerebral cortex. While the central portion of the midbody, a cytoplasmic bridge between nascent daughter cells, is engulfed by one of the daughter cell by most cells in vitro, it is shown to be released into the extracellular cerebrospinal fluid in vivo in mouse embryos. Several proteins have been involved in midbody release; however, few studies have addressed the participation of the plasma membrane’s lipids in this process. Here, we show by Shotgun Lipidomic analysis that phosphatydylserine (PS, among other lipids, is enriched in the released midbodies compared to lipoparticles and cellular membranes, both collected from the cerebrospinal fluid of the developing mouse embryos. Moreover, the developing mouse embryo neural progenitor cells released two distinct types of midbodies carrying either internalized PS or externalized PS on their membrane. This strongly suggests that phagocytosis and an alternative fate of released midbodies exists. HeLa cells, which are known to mainly engulf the midbody show almost no PS exposure, if any, on the outer leaflet of the midbody membrane. These results point towards that PS exposure might be involved in the selection of recipients of released midbodies, either to be engulfed by daughter cells or phagocytosed by non-daughter cells or another cell type in the developing cerebral cortex.

  12. Derivation of myoepithelial progenitor cells from bipotent mammary stem/progenitor cells.

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    Xiangshan Zhao

    Full Text Available There is increasing evidence that breast and other cancers originate from and are maintained by a small fraction of stem/progenitor cells with self-renewal properties. Recent molecular profiling has identified six major subtypes of breast cancer: basal-like, ErbB2-overexpressing, normal breast epithelial-like, luminal A and B, and claudin-low subtypes. To help understand the relationship among mammary stem/progenitor cells and breast cancer subtypes, we have recently derived distinct hTERT-immortalized human mammary stem/progenitor cell lines: a K5(+/K19(- type, and a K5(+/K19(+ type. Under specific culture conditions, bipotent K5(+/K19(- stem/progenitor cells differentiated into stable clonal populations that were K5(-/K19(- and exhibit self-renewal and unipotent myoepithelial differentiation potential in contrast to the parental K5(+/K19(- cells which are bipotent. These K5(-/K19(- cells function as myoepithelial progenitor cells and constitutively express markers of an epithelial to mesenchymal transition (EMT and show high invasive and migratory abilities. In addition, these cells express a microarray signature of claudin-low breast cancers. The EMT characteristics of an un-transformed unipotent mammary myoepithelial progenitor cells together with claudin-low signature suggests that the claudin-low breast cancer subtype may arise from myoepithelial lineage committed progenitors. Availability of immortal MPCs should allow a more definitive analysis of their potential to give rise to claudin-low breast cancer subtype and facilitate biological and molecular/biochemical studies of this disease.

  13. Transgenic mice for interleukin 3 develop motor neuron degeneration associated with autoimmune reaction against spinal cord motor neurons

    OpenAIRE

    Chavany, Christine; Vicario-Abejón, Carlos; Miller, Georgina; Jendoubi, Moncef

    1998-01-01

    Interleukin 3 (IL-3) stimulates the proliferation and differentiation of various haematopoietic progenitor cells. Recently, IL-3 and other cytokines were reported to exert a neurotrophic activity and to be associated with neurological disorders, suggesting their complex role in the central nervous system. We now show that overexpression of IL-3 in transgenic mice causes a motor neuron disease with several features of amyotrophic lateral sclerosis and progressive muscular atrophy. These animal...

  14. Btg1 is Required to Maintain the Pool of Stem and Progenitor Cells of the Dentate Gyrus and Subventricular Zone

    Science.gov (United States)

    Farioli-Vecchioli, Stefano; Micheli, Laura; Saraulli, Daniele; Ceccarelli, Manuela; Cannas, Sara; Scardigli, Raffaella; Leonardi, Luca; Cinà, Irene; Costanzi, Marco; Ciotti, Maria Teresa; Moreira, Pedro; Rouault, Jean-Pierre; Cestari, Vincenzo; Tirone, Felice

    2012-01-01

    Btg1 belongs to a family of cell cycle inhibitory genes. We observed that Btg1 is highly expressed in adult neurogenic niches, i.e., the dentate gyrus and subventricular zone (SVZ). Thus, we generated Btg1 knockout mice to analyze the role of Btg1 in the process of generation of adult new neurons. Ablation of Btg1 causes a transient increase of the proliferating dentate gyrus stem and progenitor cells at post-natal day 7; however, at 2 months of age the number of these proliferating cells, as well as of mature neurons, greatly decreases compared to wild-type controls. Remarkably, adult dentate gyrus stem and progenitor cells of Btg1-null mice exit the cell cycle after completing the S phase, express p53 and p21 at high levels and undergo apoptosis within 5 days. In the SVZ of adult (two-month-old) Btg1-null mice we observed an equivalent decrease, associated to apoptosis, of stem cells, neuroblasts, and neurons; furthermore, neurospheres derived from SVZ stem cells showed an age-dependent decrease of the self-renewal and expansion capacity. We conclude that ablation of Btg1 reduces the pool of dividing adult stem and progenitor cells in the dentate gyrus and SVZ by decreasing their proliferative capacity and inducing apoptosis, probably reflecting impairment of the control of the cell cycle transition from G1 to S phase. As a result, the ability of Btg1-null mice to discriminate among overlapping contextual memories was affected. Btg1 appears, therefore, to be required for maintaining adult stem and progenitor cells quiescence and self-renewal. PMID:22969701

  15. BTG1 is required to maintain the pool of stem and progenitor cells of dentate gyrus and subventricular zone

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    Stefano eFarioli-Vecchioli

    2012-08-01

    Full Text Available Btg1 belongs to a family of cell cycle inhibitory genes. We observed that Btg1 is highly expressed in adult neurogenic niches, i.e., the dentate gyrus and subventricular zone (SVZ. Thus, we generated Btg1 knockout mice to analyze the role of Btg1 in the process of generation of adult new neurons.Ablation of Btg1 causes a transient increase of the proliferating dentate gyrus stem and progenitor cells at post-natal day 7; however, at two months of age the number of these proliferating cells, as well as of mature neurons, greatly decreases compared to wild-type controls. Remarkably, adult dentate gyrus stem and progenitor cells of Btg1-null mice exit cell cycle after completing the S phase, highly express p53 and p21, and within 5 days undergo apoptosis. In SVZ we observed an equivalent decrease, associated to apoptosis, of Btg1-null stem cells, neuroblasts and neurons; furthermore, neurospheres derived from SVZ stem cells showed an age-dependent decrease of the self-renewal and expansion capacity.We conclude that the ablation of Btg1 reduces the pool of dividing adult stem and progenitor cells in dentate gyrus and SVZ by decreasing their proliferative capacity and inducing apoptosis, likely reflecting the impairment of the control of the cell cycle transition from G1 to S phase. As a result, the ability of Btg1-null mice to discriminate among overlapping contextual memories was affected. Thus, Btg1 appears to be required for maintaining adult stem and progenitor cells quiescence and self-renewal.

  16. Neural progenitors, patterning and ecology in neocortical origins

    Science.gov (United States)

    Aboitiz, Francisco; Zamorano, Francisco

    2013-01-01

    The anatomical organization of the mammalian neocortex stands out among vertebrates for its laminar and columnar arrangement, featuring vertically oriented, excitatory pyramidal neurons. The evolutionary origin of this structure is discussed here in relation to the brain organization of other amniotes, i.e., the sauropsids (reptiles and birds). Specifically, we address the developmental modifications that had to take place to generate the neocortex, and to what extent these modifications were shared by other amniote lineages or can be considered unique to mammals. In this article, we propose a hypothesis that combines the control of proliferation in neural progenitor pools with the specification of regional morphogenetic gradients, yielding different anatomical results by virtue of the differential modulation of these processes in each lineage. Thus, there is a highly conserved genetic and developmental battery that becomes modulated in different directions according to specific selective pressures. In the case of early mammals, ecological conditions like nocturnal habits and reproductive strategies are considered to have played a key role in the selection of the particular brain patterning mechanisms that led to the origin of the neocortex. PMID:24273496

  17. On the progenitor of V838 Monocerotis

    CERN Document Server

    Tylenda, R; Szczerba, R

    2004-01-01

    We summarize and analyze the available observational data on the progenitor and the enviroment of V838 Mon, the object that erupted in January 2002. We show that the radio and infrared observed matter in the vicinity of V838 Mon could not have its origin in mass loss from V838 Mon but is of interstellar origin. Also from the light echo evolution we conclude that the reflecting dust is of the same nature and not blown by V838 Mon in the past. This is compatible with the photometric data for the progenitor of V838 Mon, from which we exclude the possibility that the object before eruption was an evolved red giant star (AGB or RGB star). We find that most likely it was a main sequence star of \\~5-10 M_sun.

  18. Interneuron progenitor transplantation to treat CNS dysfunction

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    Muhammad O Chohan

    2016-08-01

    Full Text Available Due to the inadequacy of endogenous repair mechanisms diseases of the nervous system remain a major challenge to scientists and clinicians. Stem cell based therapy is an exciting and viable strategy that has been shown to ameliorate or even reverse symptoms of CNS dysfunction in preclinical animal models. Of particular importance has been the use of GABAergic interneuron progenitors as a therapeutic strategy. Born in the neurogenic niches of the ventral telencephalon, interneuron progenitors retain their unique capacity to disperse, integrate and induce plasticity in adult host circuitries following transplantation. Here we discuss the potential of interneuron based transplantation strategies as it relates to CNS disease therapeutics. We also discuss mechanisms underlying their therapeutic efficacy and some of the challenges that face the field.

  19. Resident mesenchymal progenitors of articular cartilage.

    Science.gov (United States)

    Candela, Maria Elena; Yasuhara, Rika; Iwamoto, Masahiro; Enomoto-Iwamoto, Motomi

    2014-10-01

    Articular cartilage has poor capacity of self-renewal and repair. Insufficient number and activity of resident mesenchymal (connective tissue) progenitors is likely one of the underlying reasons. Chondroprogenitors reside not only in the superficial zone of articular cartilage but also in other zones of articular cartilage and in the neighboring tissues, including perichondrium (groove of Ranvier), synovium and fat pad. These cells may respond to injury and contribute to articular cartilage healing. In addition, marrow stromal cells can migrate through subchondral bone when articular cartilage is damaged. We should develop drugs and methods that correctly stimulate resident progenitors for improvement of repair and inhibition of degenerative changes in articular cartilage. Copyright © 2014. Published by Elsevier B.V.

  20. Noninvasive Imaging of Administered Progenitor Cells

    Energy Technology Data Exchange (ETDEWEB)

    Steven R Bergmann, M.D., Ph.D.

    2012-12-03

    The objective of this research grant was to develop an approach for labeling progenitor cells, specifically those that we had identified as being able to replace ischemic heart cells, so that the distribution could be followed non-invasively. In addition, the research was aimed at determining whether administration of progenitor cells resulted in improved myocardial perfusion and function. The efficiency and toxicity of radiolabeling of progenitor cells was to be evaluated. For the proposed clinical protocol, subjects with end-stage ischemic coronary artery disease were to undergo a screening cardiac positron emission tomography (PET) scan using N-13 ammonia to delineate myocardial perfusion and function. If they qualified based on their PET scan, they would undergo an in-hospital protocol whereby CD34+ cells were stimulated by the administration of granulocytes-colony stimulating factor (G-CSF). CD34+ cells would then be isolated by apharesis, and labeled with indium-111 oxine. Cells were to be re-infused and subjects were to undergo single photon emission computed tomography (SPECT) scanning to evaluate uptake and distribution of labeled progenitor cells. Three months after administration of progenitor cells, a cardiac PET scan was to be repeated to evaluate changes in myocardial perfusion and/or function. Indium oxine is a radiopharmaceutical for labeling of autologous lymphocytes. Indium-111 (In-111) decays by electron capture with a t{sub ½} of 67.2 hours (2.8 days). Indium forms a saturated complex that is neutral, lipid soluble, and permeates the cell membrane. Within the cell, the indium-oxyquinolone complex labels via indium intracellular chelation. Following leukocyte labeling, ~77% of the In-111 is incorporated in the cell pellet. The presence of red cells and /or plasma reduces the labeling efficacy. Therefore, the product needed to be washed to eliminate plasma proteins. This repeated washing can damage cells. The CD34 selected product was a 90

  1. The endocannabinoid system drives neural progenitor proliferation.

    Science.gov (United States)

    Aguado, Tania; Monory, Krisztina; Palazuelos, Javier; Stella, Nephi; Cravatt, Benjamin; Lutz, Beat; Marsicano, Giovanni; Kokaia, Zaal; Guzmán, Manuel; Galve-Roperh, Ismael

    2005-10-01

    The discovery of multipotent neural progenitor (NP) cells has provided strong support for the existence of neurogenesis in the adult brain. However, the signals controlling NP proliferation remain elusive. Endocannabinoids, the endogenous counterparts of marijuana-derived cannabinoids, act as neuromodulators via presynaptic CB1 receptors and also control neural cell death and survival. Here we show that progenitor cells express a functional endocannabinoid system that actively regulates cell proliferation both in vitro and in vivo. Specifically, NPs produce endocannabinoids and express the CB1 receptor and the endocannabinoid-inactivating enzyme fatty acid amide hydrolase (FAAH). CB1 receptor activation promotes cell proliferation and neurosphere generation, an action that is abrogated in CB1-deficient NPs. Accordingly, proliferation of hippocampal NPs is increased in FAAH-deficient mice. Our results demonstrate that endocannabinoids constitute a new group of signaling cues that regulate NP proliferation and thus open novel therapeutic avenues for manipulation of NP cell fate in the adult brain.

  2. IFN gamma regulates proliferation and neuronal differentiation by STAT1 in adult SVZ niche.

    Science.gov (United States)

    Pereira, Leticia; Medina, Rebeca; Baena, Miguel; Planas, Anna M; Pozas, Esther

    2015-01-01

    The adult subventricular zone (SVZ) is the main neurogenic niche in normal adult brains of mice and rats. Interferon gamma (IFNγ) has somewhat controversially been associated with SVZ progenitor proliferation and neurogenesis. The in vivo involvement of IFNγ in the physiology of the adult SVZ niche is not fully understood and its intracellular mediators are unknown. Here we show that IFNγ, through activation of its canonical signal transducer and activator of transcription 1 (STAT1) pathway, acts specifically on Nestin+ progenitors by decreasing both progenitor proliferation and the number of cycling cells. In addition, IFNγ increases the number of neuroblasts generated without shifting glial fate determination. The final result is deficient recruitment of newborn neurons to the olfactory bulb (OB), indicating that IFNγ-induced stimulation of neuronal differentiation does not compensate for its antiproliferative effect. We conclude that IFNγ signaling via STAT1 in the SVZ acts dually as an antiproliferative and proneurogenic factor, and thereby regulates neurogenesis in normal adult brains.

  3. Endothelial progenitor cell biology in ankylosing spondylitis.

    Science.gov (United States)

    Verma, Inderjeet; Syngle, Ashit; Krishan, Pawan

    2015-03-01

    Endothelial progenitor cells (EPCs) are unique populations which have reparative potential in overcoming endothelial damage and reducing cardiovascular risk. Patients with ankylosing spondylitis (AS) have increased risk of cardiovascular morbidity and mortality. The aim of this study was to investigate the endothelial progenitor cell population in AS patients and its potential relationships with disease variables. Endothelial progenitor cells were measured in peripheral blood samples from 20 AS and 20 healthy controls by flow cytometry on the basis of CD34 and CD133 expression. Disease activity was evaluated by using Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). Functional ability was monitored by using Bath Ankylosing Spondylitis Functional Index (BASFI). EPCs were depleted in AS patients as compared to healthy controls (CD34(+) /CD133(+) : 0.027 ± 0.010% vs. 0.044 ± 0.011%, P < 0.001). EPC depletions were significantly associated with disease duration (r = -0.52, P = 0.01), BASDAI (r = -0.45, P = 0.04) and C-reactive protein (r = -0.5, P = 0.01). This is the first study to demonstrate endothelial progenitor cell depletion in AS patients. EPC depletions inversely correlate with disease duration, disease activity and inflammation, suggesting the pivotal role of inflammation in depletion of EPCs. EPC would possibly also serve as a therapeutic target for preventing cardiovascular disease in AS. © 2014 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

  4. Isolation of Human Induced Pluripotent Stem Cell-Derived Dopaminergic Progenitors by Cell Sorting for Successful Transplantation

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    Daisuke Doi

    2014-03-01

    Full Text Available Human induced pluripotent stem cells (iPSCs can provide a promising source of midbrain dopaminergic (DA neurons for cell replacement therapy for Parkinson’s disease. However, iPSC-derived donor cells inevitably contain tumorigenic or inappropriate cells. Here, we show that human iPSC-derived DA progenitor cells can be efficiently isolated by cell sorting using a floor plate marker, CORIN. We induced DA neurons using scalable culture conditions on human laminin fragment, and the sorted CORIN+ cells expressed the midbrain DA progenitor markers, FOXA2 and LMX1A. When transplanted into 6-OHDA-lesioned rats, the CORIN+ cells survived and differentiated into midbrain DA neurons in vivo, resulting in significant improvement of the motor behavior, without tumor formation. In particular, the CORIN+ cells in a NURR1+ cell-dominant stage exhibited the best survival and function as DA neurons. Our method is a favorable strategy in terms of scalability, safety, and efficiency and may be advantageous for clinical application.

  5. Concomitant multipotent and unipotent dental pulp progenitors and their respective contribution to mineralised tissue formation

    Directory of Open Access Journals (Sweden)

    S Dimitrova-Nakov

    2012-05-01

    Full Text Available Upon in vitro induction or in vivo implantation, the stem cells of the dental pulp display hallmarks of odontoblastic, osteogenic, adipogenic or neuronal cells. However, whether these phenotypes result from genuine multipotent cells or from coexistence of distinct progenitors is still an open question. Furthermore, determining whether a single cell-derived progenitor is capable of undergoing a differentiation cascade leading to tissue repair in situ is important for the development of cell therapy strategies. Three clonal pulp precursor cell lines (A4, C5, H8, established from embryonic ED18 first molars of mouse transgenic for a recombinant plasmid adeno-SV40, were induced to differentiate towards the odonto/osteogenic, chondrogenic or adipogenic programme. Expression of phenotypic markers of each lineage was evaluated by RT-PCR, histochemistry or immunocytochemistry. The clones were implanted into mandibular incisors or calvaria of adult mice. The A4 clone was capable of being recruited towards at least 3 mesodermal lineages in vitro and of contributing to dentin-like or bone formation, in vivo, thus behaving as a multipotent cell. In contrast, the C5 and H8 clones displayed a more restricted potential. Flow cytometric analysis revealed that isolated monopotent and multipotent clones could be distinguished by a differential expression of CD90. Altogether, isolation of these clonal lines allowed demonstrating the coexistence of multipotential and restricted-lineage progenitors in the mouse pulp. These cells may further permit unravelling specificities of the different types of pulp progenitors, hence facilitating the development of cell-based therapies of the dental pulp or other cranio-facial tissues.

  6. PROPERTIES OF PROLIFERATION AND DIFFERENTIATION OF NEONATAL RAT RETINAL PROGENITOR CELLS IN VITRO

    Institute of Scientific and Technical Information of China (English)

    Kang Qianyan; Liu Yong; Zhao Jianjun; Qiu Fen; Chen Xinlin; Tian Yumei; Hu Ming

    2006-01-01

    Objective To investigate the properties of proliferation and differentiation of neonatal rat retinal progenitor cells (RPCs) in vitro. Methods RPCs were isolated from neonatal SD rats neural retina and cultured in DMEM/F12+N2 with EGF and bFGF (suspension medium )or 10%FBS without EGF and bFGF (differentiation medium). The cells grew as suspended spheres or adherent monolayers, depending on different culture conditions. The neural stem cells or retinal progenitors, neurons, astrocytes, retinal ganglion cells, rod photoreceptors and the proliferating cells were evaluated with immunofluorescence analysis by Nestin or Pax6, Map2, GFAP, Thy-1, Rhodopsin and BrdU antibodies respectively. Results RPCs could propagate and differentiate in suspension or differentiation medium and express the markers of Nestin (92.86%) or Pax6 (86.75%), Map2 (38.54%), GFAP (20.93%), Thy-1 (27.66%) and Rhodopsin(13.33%)in suspension medium; however, Nestin (60.27%), Pax6 (52%), Map2 (34.94%), GFAP (38.17%), Thy-1(30.84%) and Rhodopsin (34.67%) in differentiation medium. 96.4% of the population in the neurospheres was BrdU-positive cells. The cells could spontaneously adherent forming some subspheres and retinal specific cell types. Conclusion Neonatal rat RPCs possess the high degree of proliferation and can differentiate into neurons, astrocytes, retinal ganglion cells and rod photoreceptors in vitro. There are different proportions for RPCs to differentiate into specific cell types.

  7. Distribution of neurosensory progenitor pools during inner ear morphogenesis unveiled by cell lineage reconstruction

    Science.gov (United States)

    Dyballa, Sylvia; Savy, Thierry; Germann, Philipp; Mikula, Karol; Remesikova, Mariana; Špir, Róbert; Zecca, Andrea; Peyriéras, Nadine; Pujades, Cristina

    2017-01-01

    Reconstructing the lineage of cells is central to understanding how the wide diversity of cell types develops. Here, we provide the neurosensory lineage reconstruction of a complex sensory organ, the inner ear, by imaging zebrafish embryos in vivo over an extended timespan, combining cell tracing and cell fate marker expression over time. We deliver the first dynamic map of early neuronal and sensory progenitor pools in the whole otic vesicle. It highlights the remodeling of the neuronal progenitor domain upon neuroblast delamination, and reveals that the order and place of neuroblasts’ delamination from the otic epithelium prefigure their position within the SAG. Sensory and non-sensory domains harbor different proliferative activity contributing distinctly to the overall growth of the structure. Therefore, the otic vesicle case exemplifies a generic morphogenetic process where spatial and temporal cues regulate cell fate and functional organization of the rudiment of the definitive organ. DOI: http://dx.doi.org/10.7554/eLife.22268.001 PMID:28051766

  8. The complexity of the calretinin-expressing progenitors in the human cerebral cortex

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    Nevena V Radonjic

    2014-08-01

    Full Text Available The complex structure and function of the cerebral cortex critically depend on the balance of excitation and inhibition provided by the pyramidal projection neurons and GABAergic interneurons, respectively. The calretinin-expressing (CalR+ cell is a subtype of GABAergic cortical interneurons that is more prevalent in humans than in rodents. In rodents, CalR+ interneurons originate in the caudal ganglionic eminence (CGE from Gsx2+ progenitors, but in humans it has been suggested that a subpopulation of CalR+ cells can also be generated in the cortical ventricular/subventricular zone (VZ/SVZ. The progenitors for cortically generated CalR+ subpopulation in primates are not yet characterized. Hence, the aim of this study was to identify patterns of expression of the transcription factors (TFs that commit cortical stem cells to the CalR fate, with a focus on Gsx2. First, we studied the expression of Gsx2 and its downstream effectors, Ascl1 and Sp8 in the cortical regions of the fetal human forebrain at midgestation. Next, we established that a subpopulation of cells expressing these TFs are proliferating in the cortical SVZ, and can be co-labeled with CalR. The presence and proliferation of Gsx2+ cells, not only in the ventral telencephalon (GE as previously reported, but also in the cerebral cortex suggests cortical origin of a subpopulation of CalR+ neurons in humans. In vitro treatment of human cortical progenitors with Sonic hedgehog (Shh, an important morphogen in the specification of interneurons, decreased levels of Ascl1 and Sp8 proteins, but did not affect Gsx2 levels. Taken together, our ex-vivo and in vitro results on human fetal brain suggest complex endogenous and exogenous regulation of TFs implied in the specification of different subtypes of CalR+ cortical interneurons.

  9. Ror family receptor tyrosine kinases regulate the maintenance of neural progenitor cells in the developing neocortex.

    Science.gov (United States)

    Endo, Mitsuharu; Doi, Ryosuke; Nishita, Michiru; Minami, Yasuhiro

    2012-04-15

    The Ror family receptor tyrosine kinases (RTKs), Ror1 and Ror2, have been shown to play crucial roles in developmental morphogenesis by acting as receptors or co-receptors to mediate Wnt5a-induced signaling. Although Ror1, Ror2 and Wnt5a are expressed in the developing brain, little is known about their roles in the neural development. Here we show that Ror1, Ror2 and their ligand Wnt5a are highly expressed in neocortical neural progenitor cells (NPCs). Small interfering RNA (siRNA)-mediated suppression of Ror1, Ror2 or Wnt5a in cultured NPCs isolated from embryonic neocortex results in the reduction of βIII-tubulin-positive neurons that are produced from NPCs possibly through the generation of T-box brain 2 (Tbr2)-positive intermediate progenitors. BrdU-labeling experiments further reveal that the proportion of proliferative and neurogenic NPCs, which are positive for neural progenitor cell marker (Pax6) but negative for glial cell marker (glial fibrillary acidic protein; GFAP), is reduced within a few days in culture following knockdown of these molecules, suggesting that Ror1, Ror2 and Wnt5a regulate neurogenesis through the maintenance of NPCs. Moreover, we show that Dishevelled 2 (Dvl2) is involved in Wnt5a-Ror1 and Wnt5a-Ror2 signaling in NPCs, and that suppressed expression of Dvl2 indeed reduces the proportion of proliferative and neurogenic NPCs. Interestingly, suppressed expression of either Ror1 or Ror2 in NPCs in the developing neocortex results in the precocious differentiation of NPCs into neurons, and their forced expression results in delayed differentiation. Collectively, these results indicate that Wnt5a-Ror1 and Wnt5a-Ror2 signaling pathways play roles in maintaining proliferative and neurogenic NPCs during neurogenesis of the developing neocortex.

  10. c-Myc Enhances Sonic Hedgehog-Induced Medulloblastoma Formation from Nestin-Expressing Neural Progenitors in Mice

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    Ganesh Rao

    2003-05-01

    Full Text Available Medulloblastomas are malignant brain tumors that arise in the cerebella of children. The presumed cellsof-origin are undifferentiated precursors of granule neurons that occupy the external granule layer (EGL of the developing cerebellum. The overexpression of proteins that normally stimulate proliferation of neural progenitor cells may initiate medulloblastoma formation. Two known mitogens for neural progenitors are the c-Myc oncoprotein and Sonic hedgehog (Shh, a crucial determinant of embryonic pattern formation in the central nervous system. We modeled the ability of c-Myc and Shh to induce medulloblastoma in mice using the RCAS/tv-a system, which allows postnatal gene transfer and expression in a cell type-specific manner. We targeted the expression of Shh and c-Myc to nestin-expressing neural progenitor cells by injecting replication-competent ALV splice acceptor (RCAS vectors into the cerebella of newborn mice. Following injection with RCAS-Shh alone, 3/32 (9% mice developed medulloblastomas and 5/32 showed multifocal hyperproliferation of the EGL, possibly a precursor stage of medulloblastoma. Following injection with RCAS-Shh plus RCAS-Myc, 9/39 (23% mice developed medulloblastomas. We conclude that nestin-expressing neural progenitors, present in the cerebellum at birth, can act as the cells-of-origin for medulloblastoma, and that c-Myc cooperates with Shh to enhance tumorigenicity.

  11. Generation of high-purity human ventral midbrain dopaminergic progenitors for in vitro maturation and intracerebral transplantation.

    Science.gov (United States)

    Nolbrant, Sara; Heuer, Andreas; Parmar, Malin; Kirkeby, Agnete

    2017-09-01

    Generation of precisely patterned neural cells from human pluripotent stem cells (hPSCs) is instrumental in developing disease models and stem cell therapies. Here, we provide a detailed 16-d protocol for obtaining high-purity ventral midbrain (VM) dopamine (DA) progenitors for intracerebral transplantation into animal models and for in vitro maturation into neurons. We have successfully transplanted such cells into the rat; however, in principle, the cells can be used for transplantation into any animal model, and the protocol is designed to also be compatible with clinical transplantation into humans. We show how to precisely set the balance of patterning factors to obtain specifically the caudal VM progenitors that give rise to DA-rich grafts. By specifying how to perform quality control (QC), troubleshooting and adaptation of the procedure, this protocol will facilitate implementation in different laboratories and with a variety of hPSC lines. To facilitate reproducibility of experiments and enable shipping of cells between centers, we present a method for cryopreservation of the progenitors for subsequent direct transplantation or terminal differentiation into DA neurons. This protocol is free of xeno-derived products and can be performed under good manufacturing practice (GMP) conditions.

  12. Characterization of neural stem/progenitor cells expressing VEGF and its receptors in the subventricular zone of newborn piglet brain.

    Science.gov (United States)

    Ara, Jahan; Fekete, Saskia; Zhu, Anli; Frank, Melissa

    2010-09-01

    Neural stem/progenitor cell (NSP) biology and neurogenesis in adult central nervous system (CNS) are important both towards potential future therapeutic applications for CNS repair, and for the fundamental function of the CNS. In the present study, we report the characterization of NSP population from subventricular zone (SVZ) of neonatal piglet brain using in vivo and in vitro systems. We show that the nestin and vimentin-positive neural progenitor cells are present in the SVZ of the lateral ventricles of neonatal piglet brain. In vitro, piglet NSPs proliferated as neurospheres, expressed the typical protein of neural progenitors, nestin and a range of well-established neurodevelopmental markers. Upon dissociation and subculture, piglet NSPs differentiated into neurons and glial cells. Clonal analysis demonstrates that piglet NSPs are multipotent and retain the capacity to generate both glia and neurons. These cells expressed VEGF, VEGFR1, VEGFR2 and Neuropilin-1 and -2 mRNAs. Real time PCR revealed that SVZ NSPs from newborn piglet expressed total VEGF and all VEGF splice variants. These findings show that piglet NSPs may be helpful to more effectively design growth factor based strategies to enhance endogenous precursor cells for cell transplantation studies potentially leading to the application of this strategy in the nervous system disease and injury.

  13. Overproduction of Upper-Layer Neurons in the Neocortex Leads to Autism-like Features in Mice

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    Wei-Qun Fang

    2014-12-01

    Full Text Available The functional integrity of the neocortex depends upon proper numbers of excitatory and inhibitory neurons; however, the consequences of dysregulated neuronal production during the development of the neocortex are unclear. As excess cortical neurons are linked to the neurodevelopmental disorder autism, we investigated whether the overproduction of neurons leads to neocortical malformation and malfunction in mice. We experimentally increased the number of pyramidal neurons in the upper neocortical layers by using the small molecule XAV939 to expand the intermediate progenitor population. The resultant overpopulation of neurons perturbs development of dendrites and spines of excitatory neurons and alters the laminar distribution of interneurons. Furthermore, these phenotypic changes are accompanied by dysregulated excitatory and inhibitory synaptic connection and balance. Importantly, these mice exhibit behavioral abnormalities resembling those of human autism. Thus, our findings collectively suggest a causal relationship between neuronal overproduction and autism-like features, providing developmental insights into the etiology of autism.

  14. Overproduction of upper-layer neurons in the neocortex leads to autism-like features in mice.

    Science.gov (United States)

    Fang, Wei-Qun; Chen, Wei-Wei; Jiang, Liwen; Liu, Kai; Yung, Wing-Ho; Fu, Amy K Y; Ip, Nancy Y

    2014-12-11

    The functional integrity of the neocortex depends upon proper numbers of excitatory and inhibitory neurons; however, the consequences of dysregulated neuronal production during the development of the neocortex are unclear. As excess cortical neurons are linked to the neurodevelopmental disorder autism, we investigated whether the overproduction of neurons leads to neocortical malformation and malfunction in mice. We experimentally increased the number of pyramidal neurons in the upper neocortical layers by using the small molecule XAV939 to expand the intermediate progenitor population. The resultant overpopulation of neurons perturbs development of dendrites and spines of excitatory neurons and alters the laminar distribution of interneurons. Furthermore, these phenotypic changes are accompanied by dysregulated excitatory and inhibitory synaptic connection and balance. Importantly, these mice exhibit behavioral abnormalities resembling those of human autism. Thus, our findings collectively suggest a causal relationship between neuronal overproduction and autism-like features, providing developmental insights into the etiology of autism.

  15. 3D Normal Human Neural Progenitor Tissue-Like Assemblies: A Model of Persistent VZV Infection

    Science.gov (United States)

    Goodwin, Thomas J.

    2013-01-01

    Varicella-zoster virus (VZV) is a neurotropic human alphaherpesvirus that causes varicella upon primary infection, establishes latency in multiple ganglionic neurons, and can reactivate to cause zoster. Live attenuated VZV vaccines are available; however, they can also establish latent infections and reactivate. Studies of VZV latency have been limited to the analyses of human ganglia removed at autopsy, as the virus is strictly a human pathogen. Recently, terminally differentiated human neurons have received much attention as a means to study the interaction between VZV and human neurons; however, the short life-span of these cells in culture has limited their application. Herein, we describe the construction of a model of normal human neural progenitor cells (NHNP) in tissue-like assemblies (TLAs), which can be successfully maintained for at least 180 days in three-dimensional (3D) culture, and exhibit an expression profile similar to that of human trigeminal ganglia. Infection of NHNP TLAs with cell-free VZV resulted in a persistent infection that was maintained for three months, during which the virus genome remained stable. Immediate-early, early and late VZV genes were transcribed, and low-levels of infectious VZV were recurrently detected in the culture supernatant. Our data suggest that NHNP TLAs are an effective system to investigate long-term interactions of VZV with complex assemblies of human neuronal cells.

  16. Mobilization of hematopoietic progenitor cells in patients with liver cirrhosis

    Institute of Scientific and Technical Information of China (English)

    Ursula; M; Gehling; Marc; Willems; Kathleen; Schlagner; Ralf; A; Benndorf; Maura; Dandri; Jrg; Petersen; Martina; Sterneck; Joerg-Matthias; Pollok; Dieter; K; Hossfeld; Xavier; Rogiers

    2010-01-01

    AIM:To test the hypothesis that liver cirrhosis is associated with mobilization of hematopoietic progenitor cells. METHODS:Peripheral blood samples from 72 patients with liver cirrhosis of varying etiology were analyzed by flow cytometry.Identified progenitor cell subsets were immunoselected and used for functional assays in vitro. Plasma levels of stromal cell-derived factor-1(SDF-1) were measured using an enzyme linked immunosorbent assay.RESULTS:Progenitor cells with a CD133 + /CD45 + CD14 + phenotype we...

  17. Identification, Characterization, and Utilization of Adult Meniscal Progenitor Cells

    Science.gov (United States)

    2015-09-01

    AWARD NUMBER: W81XWH-13-1-0244 TITLE: Identification, Characterization, and Utilization of Adult Meniscal Progenitor Cells PRINCIPAL...2014 - 31 Aug 2015 4. TITLE AND SUBTITLE Identification, Characterization, and Utilization of Adult Meniscal Progenitor Cells 5a. CONTRACT NUMBER 5b...the development of knee osteoarthritis (OA). New treatments centered on the stem/ progenitor cell population resident within the adult meniscus will be

  18. Lin28 sustains early renal progenitors and induces Wilms tumor

    National Research Council Canada - National Science Library

    Urbach, Achia; Yermalovich, Alena; Zhang, Jin; Spina, Catherine S; Zhu, Hao; Perez-Atayde, Antonio R; Shukrun, Rachel; Charlton, Jocelyn; Sebire, Neil; Mifsud, William; Dekel, Benjamin; Pritchard-Jones, Kathy; Daley, George Q

    2014-01-01

    .... Here we show that overexpression of the heterochronic regulator Lin28 during kidney development in mice markedly expands nephrogenic progenitors by blocking their final wave of differentiation...

  19. Postembryonic neuronal addition in Zebrafish dorsal root ganglia is regulated by Notch signaling

    Directory of Open Access Journals (Sweden)

    McGraw Hillary

    2012-06-01

    Full Text Available Abstract Background The sensory neurons and glia of the dorsal root ganglia (DRG arise from neural crest cells in the developing vertebrate embryo. In mouse and chick, DRG formation is completed during embryogenesis. In contrast, zebrafish continue to add neurons and glia to the DRG into adulthood, long after neural crest migration is complete. The molecular and cellular regulation of late DRG growth in the zebrafish remains to be characterized. Results In the present study, we use transgenic zebrafish lines to examine neuronal addition during postembryonic DRG growth. Neuronal addition is continuous over the period of larval development. Fate-mapping experiments support the hypothesis that new neurons are added from a population of resident, neural crest-derived progenitor cells. Conditional inhibition of Notch signaling was used to assess the role of this signaling pathway in neuronal addition. An increase in the number of DRG neurons is seen when Notch signaling is inhibited during both early and late larval development. Conclusions Postembryonic growth of the zebrafish DRG comes about, in part, by addition of new neurons from a resident progenitor population, a process regulated by Notch signaling.

  20. [Neuronal network].

    Science.gov (United States)

    Langmeier, M; Maresová, D

    2005-01-01

    Function of the central nervous system is based on mutual relations among the nerve cells. Description of nerve cells and their processes, including their contacts was enabled by improvement of optical features of the microscope and by the development of impregnation techniques. It is associated with the name of Antoni van Leeuwenhoek (1632-1723), J. Ev. Purkyne (1787-1869), Camillo Golgi (1843-1926), and Ramón y Cajal (1852-1934). Principal units of the neuronal network are the synapses. The term synapse was introduced into neurophysiology by Charles Scott Sherrington (1857-1952). Majority of the interactions between nerve cells is mediated by neurotransmitters acting at the receptors of the postsynaptic membrane or at the autoreceptors of the presynaptic part of the synapse. Attachment of the vesicles to the presynaptic membrane and the release of the neurotransmitter into the synaptic cleft depend on the intracellular calcium concentration and on the presence of several proteins in the presynaptic element.

  1. Optimizing Culture Medium Composition to Improve Oligodendrocyte Progenitor Cell Yields In Vitro from Subventricular Zone-Derived Neural Progenitor Cell Neurospheres

    Science.gov (United States)

    Franco, Paula G.; Pasquini, Juana M.; Silvestroff, Lucas

    2015-01-01

    Neural Stem and Progenitor Cells (NSC/NPC) are gathering tangible recognition for their uses in cell therapy and cell replacement therapies for human disease, as well as a model system to continue research on overall neural developmental processes in vitro. The Subventricular Zone is one of the largest NSC/NPC niches in the developing mammalian Central Nervous System, and persists through to adulthood. Oligodendrocyte progenitor cell (OPC) enriched cultures are usefull tools for in vitro studies as well as for cell replacement therapies for treating demyelination diseases. We used Subventricular Zone-derived NSC/NPC primary cultures from newborn mice and compared the effects of different growth factor combinations on cell proliferation and OPC yield. The Platelet Derived Growth Factor-AA and BB homodimers had a positive and significant impact on OPC generation. Furthermore, heparin addition to the culture media contributed to further increase overall culture yields. The OPC generated by this protocol were able to mature into Myelin Basic Protein-expressing cells and to interact with neurons in an in vitro co-culture system. As a whole, we describe an optimized in vitro method for increasing OPC. PMID:25837625

  2. Optimizing culture medium composition to improve oligodendrocyte progenitor cell yields in vitro from subventricular zone-derived neural progenitor cell neurospheres.

    Science.gov (United States)

    Franco, Paula G; Pasquini, Juana M; Silvestroff, Lucas

    2015-01-01

    Neural Stem and Progenitor Cells (NSC/NPC) are gathering tangible recognition for their uses in cell therapy and cell replacement therapies for human disease, as well as a model system to continue research on overall neural developmental processes in vitro. The Subventricular Zone is one of the largest NSC/NPC niches in the developing mammalian Central Nervous System, and persists through to adulthood. Oligodendrocyte progenitor cell (OPC) enriched cultures are usefull tools for in vitro studies as well as for cell replacement therapies for treating demyelination diseases. We used Subventricular Zone-derived NSC/NPC primary cultures from newborn mice and compared the effects of different growth factor combinations on cell proliferation and OPC yield. The Platelet Derived Growth Factor-AA and BB homodimers had a positive and significant impact on OPC generation. Furthermore, heparin addition to the culture media contributed to further increase overall culture yields. The OPC generated by this protocol were able to mature into Myelin Basic Protein-expressing cells and to interact with neurons in an in vitro co-culture system. As a whole, we describe an optimized in vitro method for increasing OPC.

  3. Distribution and localization of fibroblast growth factor-8 in rat brain and nerve cells during neural stem/progenitor cell differentiation

    Institute of Scientific and Technical Information of China (English)

    Jiang Lu; Dongsheng Li; Kehuan Lu

    2012-01-01

    The present study explored the distribution and localization of fibroblast growth factor-8 and its potential receptor,fibroblast growth factor receptor-3,in adult rat brain in vivo and in nerve cells during differentiation of neural stem/progenitor cells in vitro.Immunohistochemistry was used to examine the distribution of fibroblast growth factor-8 in adult rat brain in vivo.Localization of fibroblast growth factor-8 and fibroblast growth factor receptor-3 in cells during neural stem/progenitor cell differentiation in vitro was detected by immunofluorescence.Flow cytometry and immunofluorescence were used to evaluate the effect of an anti-fibroblast growth factor-8 antibody on neural stem/progenitor cell differentiation and expansion in vitro.Results from this study confirmed that fibroblast growth factor-8 was mainly distributed in adult midbrain,namely the substantia nigra,compact part,dorsal tier,substantia nigra and reticular part,but was not detected in the forebrain comprising the caudate putamen and striatum.Unusual results were obtained in retrosplenial locations of adult rat brain.We found that fibroblast growth factor-8 and fibroblast growth factor receptor-3 were distributed on the cell membrane and in the cytoplasm of nerve cells using immunohistochemistry and immunofluorescence analyses.We considered that the distribution of fibroblast growth factor-8 and fibroblast growth factor receptor-3 in neural cells corresponded to the characteristics of fibroblast growth factor-8,a secretory factor.Addition of an anti-fibroblast growth factor-8 antibody to cultures significantly affected the rate of expansion and differentiation of neural stem/progenitor cells.In contrast,addition of recombinant fibroblast growth factor-8 to differentiation medium promoted neural stem/progenitor cell differentiation and increased the final yields of dopaminergic neurons and total neurons.Our study may help delineate the important roles of fibroblast growth factor-8 in brain

  4. The timing of upper-layer neurogenesis is conferred by sequential derepression and negative feedback from deep-layer neurons.

    Science.gov (United States)

    Toma, Kenichi; Kumamoto, Takuma; Hanashima, Carina

    2014-09-24

    The prevailing view of upper-layer (UL) neurogenesis in the cerebral cortex is that progenitor cells undergo successive rounds of asymmetric cell division that restrict the competence and production of UL neurons later in development. However, the recent discovery of UL fate-committed early progenitors raises an alternative perspective concerning their ontogeny. To investigate the emergence of UL progenitors, we manipulated the timing and extent of cortical neurogenesis in vivo in mice. We demonstrated that UL competence is tightly linked to deep-layer (DL) neurogenesis and that this sequence is determined primarily through derepression of Fezf2 by Foxg1 within a closed transcriptional cascade. We further demonstrated that the sequential acquisition of UL competence requires negative feedback, which is propagated from postmitotic DL neurons. Thus, neocortical progenitors integrate intrinsic and extrinsic cues to generate UL neurons through a system that controls the sequence of DL and UL neurogenesis and to scale the production of intracortical projection neurons based on the availability of their subcortical projection neuron counterparts during cortical development and evolution.

  5. Expanded CAG repeats in the murine Huntington's disease gene increases neuronal differentiation of embryonic and neural stem cells.

    Science.gov (United States)

    Lorincz, Matthew T; Zawistowski, Virginia A

    2009-01-01

    Huntington's disease is an uncommon autosomal dominant neurodegenerative disorder caused by expanded polyglutamine repeats. Increased neurogenesis was demonstrated recently in Huntington's disease post-mortem samples. In this manuscript, neuronally differentiated embryonic stem cells with expanded CAG repeats in the murine Huntington's disease homologue and neural progenitors isolated from the subventricular zone of an accurate mouse Huntington's disease were examined for increased neurogenesis. Embryonic stem cells with expanded CAG repeats in the murine Huntington's disease homologue were demonstrated to undergo facilitated differentiation first into neural progenitors, then into more mature neurons. Neural progenitor cells isolated from the subventricular zone of a Huntington's disease knock-in animal displayed increased production of neural progenitors and increased neurogenesis. These findings suggested that neuronally differentiating embryonic stem cells with expanded CAG repeats is a reasonable system to identify factors responsible for increased neurogenesis in Huntington's disease. Expression profiling analysis comparing neuronally differentiating embryonic stem cells with expanded CAG repeats to neuronally differentiating embryonic stem cells without expanded CAG repeats identified transcripts involved in development and transcriptional regulation as factors possibly mediating increased neurogenesis in response to expanded CAG repeats.

  6. Generation of New Neurons in Dorsal Root Ganglia in Adult Rats after Peripheral Nerve Crush Injury

    Directory of Open Access Journals (Sweden)

    Luisa Muratori

    2015-01-01

    Full Text Available The evidence of neurons generated ex novo in sensory ganglia of adult animals is still debated. In the present study, we investigated, using high resolution light microscopy and stereological analysis, the changes in the number of neurons in dorsal root ganglia after 30 days from a crush lesion of the rat brachial plexus terminal branches. Results showed, as expected, a relevant hypertrophy of dorsal root ganglion neurons. In addition, we reported, for the first time in the literature, that neuronal hypertrophy was accompanied by massive neuronal hyperplasia leading to a 42% increase of the number of primary sensory neurons. Moreover, ultrastructural analyses on sensory neurons showed that there was not a relevant neuronal loss as a consequence of the nerve injury. The evidence of BrdU-immunopositive neurons and neural progenitors labeled with Ki67, nanog, nestin, and sox-2 confirmed the stereological evidence of posttraumatic neurogenesis in dorsal root ganglia. Analysis of morphological changes following axonal damage in addition to immunofluorescence characterization of cell phenotype suggested that the neuronal precursors which give rise to the newly generated neurons could be represented by satellite glial cells that actively proliferate after the lesion and are able to differentiate toward the neuronal lineage.

  7. Insulin-like growth factor actions during development of neural stem cells and progenitors in the central nervous system.

    Science.gov (United States)

    Ye, Ping; D'Ercole, A Joseph

    2006-01-01

    Insulin-like growth factor-I (IGF-I) plays a key role in normal development. Recent studies show that IGF-I exerts a wide variety actions in the central nervous system during development as well as in adulthood. This report reviews recent developments on IGF-I actions and its mechanisms in the central nervous system, with a focus on its actions during the development of neural stem cells and progenitors. Available data strongly indicate that IGF-I shortens the length of the cell cycle in neuron progenitors during embryonic life and has an influence on the growth of all neural cell types. The phosphatidylinositol-3 kinase/Akt and mitogen-activated protein kinase pathways seem to be the predominant mediators of IGF-I-stimulated neural cell proliferation and survival. IGF-I actions, however, likely depend on cell type, developmental stage, and microenvironmental milieu.

  8. Focal Transplantation of Human iPSC-Derived Glial-Rich Neural Progenitors Improves Lifespan of ALS Mice

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    Takayuki Kondo

    2014-08-01

    Full Text Available Transplantation of glial-rich neural progenitors has been demonstrated to attenuate motor neuron degeneration and disease progression in rodent models of mutant superoxide dismutase 1 (SOD1-mediated amyotrophic lateral sclerosis (ALS. However, translation of these results into a clinical setting requires a renewable human cell source. Here, we derived glial-rich neural progenitors from human iPSCs and transplanted them into the lumbar spinal cord of ALS mouse models. The transplanted cells differentiated into astrocytes, and the treated mouse group showed prolonged lifespan. Our data suggest a potential therapeutic mechanism via activation of AKT signal. The results demonstrated the efficacy of cell therapy for ALS by the use of human iPSCs as cell source.

  9. Mammalian neurogenesis requires Treacle-Plk1 for precise control of spindle orientation, mitotic progression, and maintenance of neural progenitor cells.

    Directory of Open Access Journals (Sweden)

    Daisuke Sakai

    Full Text Available The cerebral cortex is a specialized region of the brain that processes cognitive, motor, somatosensory, auditory, and visual functions. Its characteristic architecture and size is dependent upon the number of neurons generated during embryogenesis and has been postulated to be governed by symmetric versus asymmetric cell divisions, which mediate the balance between progenitor cell maintenance and neuron differentiation, respectively. The mechanistic importance of spindle orientation remains controversial, hence there is considerable interest in understanding how neural progenitor cell mitosis is controlled during neurogenesis. We discovered that Treacle, which is encoded by the Tcof1 gene, is a novel centrosome- and kinetochore-associated protein that is critical for spindle fidelity and mitotic progression. Tcof1/Treacle loss-of-function disrupts spindle orientation and cell cycle progression, which perturbs the maintenance, proliferation, and localization of neural progenitors during cortical neurogenesis. Consistent with this, Tcof1(+/- mice exhibit reduced brain size as a consequence of defects in neural progenitor maintenance. We determined that Treacle elicits its effect via a direct interaction with Polo-like kinase1 (Plk1, and furthermore we discovered novel in vivo roles for Plk1 in governing mitotic progression and spindle orientation in the developing mammalian cortex. Increased asymmetric cell division, however, did not promote increased neuronal differentiation. Collectively our research has therefore identified Treacle and Plk1 as novel in vivo regulators of spindle fidelity, mitotic progression, and proliferation in the maintenance and localization of neural progenitor cells. Together, Treacle and Plk1 are critically required for proper cortical neurogenesis, which has important implications in the regulation of mammalian brain size and the pathogenesis of congenital neurodevelopmental disorders such as microcephaly.

  10. Motor neuron cell bodies are actively positioned by Slit/Robo repulsion and Netrin/DCC attraction.

    Science.gov (United States)

    Kim, Minkyung; Fontelonga, Tatiana; Roesener, Andrew P; Lee, Haeram; Gurung, Suman; Mendonca, Philipe R F; Mastick, Grant S

    2015-03-01

    Motor neurons differentiate from a ventral column of progenitors and settle in static clusters, the motor nuclei, next to the floor plate. Within these cell clusters, motor neurons receive afferent input and project their axons out to muscle targets. The molecular mechanisms that position motor neurons in the neural tube remain poorly understood. The floor plate produces several types of guidance cues with well-known roles in attracting and repelling axons, including the Slit family of chemorepellents via their Robo receptors, and Netrin1 via its DCC attractive receptor. In the present study we found that Islet1(+) motor neuron cell bodies invaded the floor plate of Robo1/2 double mutant mouse embryos or Slit1/2/3 triple mutants. Misplaced neurons were born in their normal progenitor column, but then migrated tangentially into the ventral midline. Robo1 and 2 receptor expression in motor neurons was confirmed by reporter gene staining and anti-Robo antibody labeling. Mis-positioned motor neurons projected their axons longitudinally within the floor plate, and failed to reach their normal exit points. To test for potential counteracting ventral attractive signals, we examined Netrin-1 and DCC mutants, and found that motor neurons shifted dorsally in the hindbrain and spinal cord, suggesting that Netrin-1/DCC signaling normally attracts motor neurons closer to the floor plate. Our results show that motor neurons are actively migrating cells, and are normally trapped in a static position by Slit/Robo repulsion and Netrin-1/DCC attraction.

  11. Enhancing endothelial progenitor cell for clinical use

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Circulating endothelial progenitor cells (EPCs) havebeen demonstrated to correlate negatively with vascularendothelial dysfunction and cardiovascular risk factors.However, translation of basic research into the clinicalpractice has been limited by the lack of unambiguousand consistent definitions of EPCs and reduced EPCcell number and function in subjects requiring them forclinical use. This article critically reviews the definitionof EPCs based on commonly used protocols, their valueas a biomarker of cardiovascular risk factor in subjectswith cardiovascular disease, and strategies to enhanceEPCs for treatment of ischemic diseases.

  12. Beneficial effect of cilostazol-mediated neuronal repair following trimethyltin-induced neuronal loss in the dentate gyrus.

    Science.gov (United States)

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

    2015-01-01

    Cilostazol acts as an antiplatelet agent and has other pleiotropic effects based on phosphodiesterase-3-dependent mechanisms. We evaluated whether cilostazol would have a beneficial effect on neuronal repair following hippocampal neuronal damage by using a mouse model of trimethyltin (TMT)-induced neuronal loss/self-repair in the hippocampal dentate gyrus [Ogita et al. (2005) J Neurosci Res 82:609-621]; these mice will hereafter be referred to as impaired animals. A single treatment with cilostazol (10 mg/kg, i.p.) produced no significant change in the number of 5-bromo-2'-deoxyuridine (BrdU)-incorporating cells in the dentate granule cell layer (GCL) or subgranular zone on day 3 after TMT treatment. However, chronic treatment with cilostazol on days 3-15 posttreatment resulted in an increase in the number of BrdU-incorporating cells in the dentate GCL of the impaired animals, and these cells were positive for neuronal nuclear antigen or doublecortin. Cilostazol was effective in elevating the level of phosphorylated cyclic adrenosine monophosphate response element-binding protein (pCREB) in the dentate gyrus of impaired animals. The results of a forced swimming test revealed that the chronic treatment with cilostazol improved the depression-like behavior seen in the impaired animals. In the cultures of hippocampal neural stem/progenitor cells, exposure to cilostazol produced not only enhancement of proliferation activity but also elevation of pCREB levels. Taken together, our data suggest that cilostazol has a beneficial effect on neuronal repair following neuronal loss in the dentate gyrus through promotion of proliferation and/or neuronal differentiation of neural progenitor cells in the subgranular zone. © 2014 Wiley Periodicals, Inc.

  13. Zebrafish adult-derived hypothalamic neurospheres generate gonadotropin-releasing hormone (GnRH) neurons

    Science.gov (United States)

    Cortés-Campos, Christian; Letelier, Joaquín; Ceriani, Ricardo; Whitlock, Kathleen E.

    2015-01-01

    ABSTRACT Gonadotropin-releasing hormone (GnRH) is a hypothalamic decapeptide essential for fertility in vertebrates. Human male patients lacking GnRH and treated with hormone therapy can remain fertile after cessation of treatment suggesting that new GnRH neurons can be generated during adult life. We used zebrafish to investigate the neurogenic potential of the adult hypothalamus. Previously we have characterized the development of GnRH cells in the zebrafish linking genetic pathways to the differentiation of neuromodulatory and endocrine GnRH cells in specific regions of the brain. Here, we developed a new method to obtain neural progenitors from the adult hypothalamus in vitro. Using this system, we show that neurospheres derived from the adult hypothalamus can be maintained in culture and subsequently differentiate glia and neurons. Importantly, the adult derived progenitors differentiate into neurons containing GnRH and the number of cells is increased through exposure to either testosterone or GnRH, hormones used in therapeutic treatment in humans. Finally, we show in vivo that a neurogenic niche in the hypothalamus contains GnRH positive neurons. Thus, we demonstrated for the first time that neurospheres can be derived from the hypothalamus of the adult zebrafish and that these neural progenitors are capable of producing GnRH containing neurons. PMID:26209533

  14. Zebrafish adult-derived hypothalamic neurospheres generate gonadotropin-releasing hormone (GnRH neurons

    Directory of Open Access Journals (Sweden)

    Christian Cortés-Campos

    2015-09-01

    Full Text Available Gonadotropin-releasing hormone (GnRH is a hypothalamic decapeptide essential for fertility in vertebrates. Human male patients lacking GnRH and treated with hormone therapy can remain fertile after cessation of treatment suggesting that new GnRH neurons can be generated during adult life. We used zebrafish to investigate the neurogenic potential of the adult hypothalamus. Previously we have characterized the development of GnRH cells in the zebrafish linking genetic pathways to the differentiation of neuromodulatory and endocrine GnRH cells in specific regions of the brain. Here, we developed a new method to obtain neural progenitors from the adult hypothalamus in vitro. Using this system, we show that neurospheres derived from the adult hypothalamus can be maintained in culture and subsequently differentiate glia and neurons. Importantly, the adult derived progenitors differentiate into neurons containing GnRH and the number of cells is increased through exposure to either testosterone or GnRH, hormones used in therapeutic treatment in humans. Finally, we show in vivo that a neurogenic niche in the hypothalamus contains GnRH positive neurons. Thus, we demonstrated for the first time that neurospheres can be derived from the hypothalamus of the adult zebrafish and that these neural progenitors are capable of producing GnRH containing neurons.

  15. Müller glial cells induce stem cell properties in retinal progenitors in vitro and promote their further differentiation into photoreceptors.

    Science.gov (United States)

    Simón, María V; De Genaro, Pablo; Abrahan, Carolina E; de los Santos, Beatriz; Rotstein, Nora P; Politi, Luis E

    2012-02-01

    Using stem cells to replace lost neurons is a promising strategy for treating retinal neurodegenerative diseases. Among their multiple functions, Müller glial cells are retina stem cells, with a robust regenerative potential in lower vertebrates, which is much more restricted in mammals. In rodents, most retina progenitors exit the cell cycle immediately after birth, differentiate as neurons, and then cannot reenter the cell cycle. Here we demonstrate that, in mixed cultures with Müller glial cells, rat retina progenitor cells expressed stem cell properties, maintained their proliferative potential, and were able to preserve these properties and remain mitotically active after several consecutive passages. Notably, these progenitors retained the capacity to differentiate as photoreceptors, even after successive reseedings. Müller glial cells markedly stimulated differentiation of retina progenitors; these cells initially expressed Crx and then developed as mature photoreceptors that expressed characteristic markers, such as opsin and peripherin. Moreover, they were light responsive, insofar as they decreased their cGMP levels when exposed to light, and they also showed high-affinity glutamate uptake, a characteristic of mature photoreceptors. Our present findings indicate that, in addition to giving rise to new photoreceptors, Müller glial cells might instruct a pool of undifferentiated cells to develop and preserve stem cell characteristics, even after successive reseedings, and then stimulate their differentiation as functional photoreceptors. This complementary mechanism might contribute to enlarge the limited regenerative capacity of mammalian Müller cells.

  16. Sonic hedgehog signaling coordinates the proliferation and differentiation of neural stem/progenitor cells by regulating cell cycle kinetics during development of the neocortex.

    Science.gov (United States)

    Komada, Munekazu

    2012-06-01

    Sonic hedgehog (Shh) acts as a morphogen in normal development of various vertebrate tissues and organs. Shh signaling is essential for patterning and cell-fate specification, particularly in the central nervous system. Shh signaling plays different roles depending on its concentration, area, and timing of exposure. During the development of the neocortex, a low level of Shh is expressed in the neural stem/progenitor cells as well as in mature neurons in the dorsal telencephalon. Shh signaling in neocortex development has been shown to regulate cell cycle kinetics of radial glial cells and intermediate progenitor cells, thereby maintaining the proliferation, survival and differentiation of neurons in the neocortex. During the development of the telencephalon, endogenous Shh signaling is involved in the transition of slow-cycling neural stem cells to fast-cycling neural progenitor cells. It seems that high-level Shh signaling in the ventral telencephalon is essential for ventral specification, while low-level Shh signaling in the dorsal telencephalon plays important roles in the fine-tuning of cell cycle kinetics. The Shh levels and multiple functions of Shh signaling are important for proper corticogenesis in the developing brain. The present paper discusses the roles of Shh signaling in the proliferation and differentiation of neural stem/progenitor cells.

  17. Dedifferentiation of neurons and astrocytes by oncogenes can induce gliomas in mice.

    Science.gov (United States)

    Friedmann-Morvinski, Dinorah; Bushong, Eric A; Ke, Eugene; Soda, Yasushi; Marumoto, Tomotoshi; Singer, Oded; Ellisman, Mark H; Verma, Inder M

    2012-11-23

    Glioblastoma multiforme (GBM) is the most common and aggressive malignant primary brain tumor in humans. Here we show that gliomas can originate from differentiated cells in the central nervous system (CNS), including cortical neurons. Transduction by oncogenic lentiviral vectors of neural stem cells (NSCs), astrocytes, or even mature neurons in the brains of mice can give rise to malignant gliomas. All the tumors, irrespective of the site of lentiviral vector injection (the initiating population), shared common features of high expression of stem or progenitor markers and low expression of differentiation markers. Microarray analysis revealed that tumors of astrocytic and neuronal origin match the mesenchymal GBM subtype. We propose that most differentiated cells in the CNS upon defined genetic alterations undergo dedifferentiation to generate a NSC or progenitor state to initiate and maintain the tumor progression, as well as to give rise to the heterogeneous populations observed in malignant gliomas.

  18. Isolation of neural progenitor cells from the human adult subventricular zone based on expression of the cell surface marker CD271.

    Science.gov (United States)

    van Strien, Miriam E; Sluijs, Jacqueline A; Reynolds, Brent A; Steindler, Dennis A; Aronica, Eleonora; Hol, Elly M

    2014-04-01

    Neural progenitor cells (NPCs) in the subventricular zone (SVZ) hold promise for future therapy for neurodegenerative disorders, because the stimulation of adult neurogenesis could potentially restore the function of degenerating neurons and glia. To obtain more knowledge on these NPCs, we developed a method to specifically isolate NPCs from postmortem adult human brains based on the expression of the specific human adult neural stem/progenitor cell marker glial fibrillary acidic protein δ (GFAPδ). An extensive immunophenotyping analysis for cell surface markers resulted in the observation that CD271 was limited to the SVZ-derived GFAPδ-positive cells. CD271(+) cells developed into neurospheres and could be differentiated into astrocytes, neurons, and oligodendrocytes. We are the first to show that a pure population of NPCs can be isolated from the adult human SVZ, which is highly instrumental for developing future therapies based on stimulating endogenous SVZ neurogenesis.

  19. Up-regulation of DRP-3 long isoform during the induction of neural progenitor cells by glutamate treatment in the ex vivo rat retina.

    Science.gov (United States)

    Tokuda, Kazuhiro; Kuramitsu, Yasuhiro; Byron, Baron; Kitagawa, Takao; Tokuda, Nobuko; Kobayashi, Daiki; Nagayama, Megumi; Araki, Norie; Sonoda, Koh-Hei; Nakamura, Kazuyuki

    2015-08-07

    Glutamate has been shown to induce neural progenitor cells in the adult vertebrate retina. However, protein dynamics during progenitor cell induction by glutamate are not fully understood. To identify specific proteins involved in the process, we employed two-dimensional electrophoresis-based proteomics on glutamate untreated and treated retinal ex vivo sections. Rat retinal tissues were incubated with 1 mM glutamate for 1 h, followed by incubation in glutamate-free media for a total of 24 h. Consistent with prior reports, it was found that mitotic cells appeared in the outer nuclear layer without any histological damage. Immunohistological evaluations and immunoblotting confirmed the emergence of neuronal progenitor cells in the mature retina treated with glutamate. Proteomic analysis revealed the up-regulation of dihydropyrimidinase-related protein 3 (DRP-3), DRP-2 and stress-induced-phosphoprotein 1 (STIP1) during neural progenitor cell induction by glutamate. Moreover, mRNA expression of DRP-3, especially, its long isoform, robustly increased in the treated retina compared to that in the untreated retina. These results may indicate that glutamate induces neural progenitor cells in the mature rat retina by up-regulating the proteins which mediate cell mitosis and neurite growth.

  20. Beneficial in vivo effect of aripiprazole on neuronal regeneration following neuronal loss in the dentate gyrus: evaluation using a mouse model of trimethyltin-induced neuronal loss/self-repair in the dentate gyrus.

    Science.gov (United States)

    Yoneyama, Masanori; Hasebe, Shigeru; Kawamoto, Noriko; Shiba, Tatsuo; Yamaguchi, Taro; Kikuta, Maho; Shuto, Makoto; Ogita, Kiyokazu

    2014-01-01

    Aripiprazole is used clinically as an atypical antipsychotic. We evaluated the effect of in vivo treatment with aripiprazole on the proliferation and differentiation of neural stem/progenitor cells in a mouse model, trimethyltin-induced neuronal loss/self-repair in the hippocampal dentate gyrus (referred as "impaired animals") [Ogita et al., J Neurosci Res. 82, 609 - 621 (2005)]. In the impaired animals, an increased number of 5-bromo-2'-deoxyuridine (BrdU)-positive cells was seen in the dentate gyrus at the initial time window of the self-repair stage. At the same time window, a single treatment with aripiprazole significantly increased the number of cells positive for both BrdU and nestin in the dentate gyrus of the impaired animals. Chronic treatment with aripiprazole promoted the proliferation/survival and neuronal differentiation of the cells newly-generated following the neuronal loss in the dentate gyrus of the impaired animals. The chronic treatment with aripiprazole improved depression-like behavior seen in the impaired animals. Taken together, our data suggest that aripiprazole had a beneficial effect on neuronal regeneration following neuronal loss in the dentate gyrus through indirectly promoted proliferation/survival and neuronal differentiation of neural stem/progenitor cells in the subgranular zone of the dentate gyrus.

  1. Efficient induction of dopaminergic neuron differentiation from induced pluripotent stem cells reveals impaired mitophagy in PARK2 neurons.

    Science.gov (United States)

    Suzuki, Sadafumi; Akamatsu, Wado; Kisa, Fumihiko; Sone, Takefumi; Ishikawa, Kei-Ichi; Kuzumaki, Naoko; Katayama, Hiroyuki; Miyawaki, Atsushi; Hattori, Nobutaka; Okano, Hideyuki

    2017-01-29

    Patient-specific induced pluripotent stem cells (iPSCs) show promise for use as tools for in vitro modeling of Parkinson's disease. We sought to improve the efficiency of dopaminergic (DA) neuron induction from iPSCs by the using surface markers expressed in DA progenitors to increase the significance of the phenotypic analysis. By sorting for a CD184(high)/CD44(-) fraction during neural differentiation, we obtained a population of cells that were enriched in DA neuron precursor cells and achieved higher differentiation efficiencies than those obtained through the same protocol without sorting. This high efficiency method of DA neuronal induction enabled reliable detection of reactive oxygen species (ROS) accumulation and vulnerable phenotypes in PARK2 iPSCs-derived DA neurons. We additionally established a quantitative system using the mt-mKeima reporter system to monitor mitophagy in which mitochondria fuse with lysosomes and, by combining this system with the method of DA neuronal induction described above, determined that mitophagy is impaired in PARK2 neurons. These findings suggest that the efficiency of DA neuron induction is important for the precise detection of cellular phenotypes in modeling Parkinson's disease. Copyright © 2016. Published by Elsevier Inc.

  2. Excitatory cortical neurons with multipolar shape establish neuronal polarity by forming a tangentially oriented axon in the intermediate zone.

    Science.gov (United States)

    Hatanaka, Yumiko; Yamauchi, Kenta

    2013-01-01

    The formation of axon-dendrite polarity is crucial for neuron to make the proper information flow within the brain. Although the processes of neuronal polarity formation have been extensively studied using neurons in dissociated culture, the corresponding developmental processes in vivo are still unclear. Here, we illuminate the initial steps of morphological polarization of excitatory cortical neurons in situ, by sparsely labeling their neuroepithelial progenitors using in utero electroporation and then examining their neuronal progeny in brain sections and in slice cultures. Morphological analysis showed that an axon-like long tangential process formed in progeny cells in the intermediate zone (IZ). Time-lapse imaging analysis using slice culture revealed that progeny cells with multipolar shape, after alternately extending and retracting their short processes for several hours, suddenly elongated a long process tangentially. These cells then transformed into a bipolar shape, extending a pia-directed leading process, and migrated radially leaving the tangential process behind, which gave rise to an "L-shaped" axon. Our findings suggest that neuronal polarity in these cells is established de novo from a nonpolarized stage in vivo and indicate that excitatory cortical neurons with multipolar shape in the IZ initiate axon outgrowth before radial migration into the cortical plate.

  3. The progenitors of supernovae Type Ia

    Science.gov (United States)

    Toonen, Silvia

    2014-09-01

    Despite the significance of Type Ia supernovae (SNeIa) in many fields in astrophysics, SNeIa lack a theoretical explanation. SNeIa are generally thought to be thermonuclear explosions of carbon/oxygen (CO) white dwarfs (WDs). The canonical scenarios involve white dwarfs reaching the Chandrasekhar mass, either by accretion from a non-degenerate companion (single-degenerate channel, SD) or by a merger of two CO WDs (double-degenerate channel, DD). The study of SNeIa progenitors is a very active field of research for binary population synthesis (BPS) studies. The strength of the BPS approach is to study the effect of uncertainties in binary evolution on the macroscopic properties of a binary population, in order to constrain binary evolutionary processes. I will discuss the expected SNeIa rate from the BPS approach and the uncertainties in their progenitor evolution, and compare with current observations. I will also discuss the results of the POPCORN project in which four BPS codes were compared to better understand the differences in the predicted SNeIa rate of the SD channel. The goal of this project is to investigate whether differences in the simulated populations are due to numerical effects or whether they can be explained by differences in the input physics. I will show which assumptions in BPS codes affect the results most and hence should be studied in more detail.

  4. Single degenerate supernova type Ia progenitors

    CERN Document Server

    Bours, M C P; Nelemans, G

    2013-01-01

    There is general agreement that supernovae Ia correspond to the thermonuclear runaway of a white dwarf that is part of a compact binary, but the details of the progenitor systems are still unknown and much debated. One of the proposed progenitor theories is the single-degenerate channel in which a white dwarf accretes from a companion, grows in mass, reaches a critical mass limit, and is then consumed after thermonuclear runaway sets in. However, there are major disagreements about the theoretical delay time distribution and the corresponding time-integrated supernova Ia rate from this channel. We investigate whether the differences are due to the uncertainty in the common envelope phase and the fraction of transferred mass that is retained by the white dwarf. This so-called retention efficiency may have a strong influence on the final amount and timing of supernovae Ia. Using the population synthesis code SeBa, we simulated large numbers of binaries for various assumptions on common envelopes and retention e...

  5. Galactic Constraints on Supernova Progenitor Models

    CERN Document Server

    Acharova, I; Mishurov, Yu; Kovtyukh, V

    2013-01-01

    We undertake a statistical analysis of the radial abundance distributions in the Galactic disk within a theoretical framework for Galactic chemical evolution which incorporates the influence of spiral arms. 1) The mean mass of oxygen ejected per core-collapse SNe (CC SNe) event (which are concentrated within spiral arms) is $\\sim$0.27 M$_{\\odot}$; 2) the mean mass of iron ejected by `tardy' Type Ia SNe (SNeIa; progenitors of whom are older/longer-lived stars with ages $\\simgt$100 Myr and up to several Gyr, which do not concentrate within spiral arms) is $\\sim$0.58 M$_{\\odot}$; 3) the upper mass of iron ejected by prompt SNeIa (SNe whose progenitors are younger/shorter-lived stars with ages $\\simlt$100 Myr, which are concentrated within spiral arms) is $\\leq$0.23 M$_{\\odot}$ per event; 4) the corresponding mean mass of iron produced by CC SNe is $\\leq$0.04 M$_{\\odot}$ per event; (v) short-lived SNe (core-collapse or prompt SNeIa) supply $\\sim$85% of the Galactic disk's iron. The inferred low mean mass of oxyge...

  6. Magnetized massive stars as magnetar progenitors

    CERN Document Server

    Hu, Ren-Yu

    2009-01-01

    The origin of ultra-intense magnetic fields on magnetars is a mystery in modern astrophysics. We model the core collapse dynamics of massive progenitor stars with high surface magnetic fields in the theoretical framework of a self-similar general polytropic magnetofluid under the self-gravity with a quasi-spherical symmetry. With the specification of physical parameters such as mass density, temperature, magnetic field and wind mass loss rate on the progenitor stellar surface and the consideration of a rebound shock breaking through the stellar interior and envelope, we find a remnant compact object (i.e. neutron star) left behind at the centre with a radius of $\\sim 10^6$ cm and a mass range of $\\sim 1-3$ solar masses. Moreover, we find that surface magnetic fields of such kind of compact objects can be $\\sim 10^{14}-10^{15}$ G, consistent with those inferred for magnetars which include soft gamma-ray repeaters (SGRs) and anomalous X-ray pulsars (AXPs). The magnetic field enhancement factor critically depend...

  7. Endothelial Progenitor Cells Enter the Aging Arena.

    Directory of Open Access Journals (Sweden)

    Kate eWilliamson

    2012-02-01

    Full Text Available Age is a significant risk factor for the development of vascular diseases, such as atherosclerosis. Although pharmacological treatments, including statins and anti-hypertensive drugs, have improved the prognosis for patients with cardiovascular disease, it remains a leading cause of mortality in those aged 65 years and over. Furthermore, given the increased life expectancy of the population in developed countries, there is a clear need for alternative treatment strategies. Consequently, the relationship between aging and progenitor cell-mediated repair is of great interest. Endothelial progenitor cells (EPCs play an integral role in the cellular repair mechanisms for endothelial regeneration and maintenance. However, EPCs are subject to age-associated changes that diminish their number in circulation and function, thereby enhancing vascular disease risk. A great deal of research is aimed at developing strategies to harness the regenerative capacity of these cells.In this review, we discuss the current understanding of the cells termed ‘EPCs’, examine the impact of age on EPC-mediated repair and identify therapeutic targets with potential for attenuating the age-related decline in vascular health via beneficial actions on EPCs.

  8. Retinal progenitor cell xenografts to the pig retina

    DEFF Research Database (Denmark)

    Warfvinge, Karin; Kiilgaard, Jens Folke; Lavik, Erin B;

    2005-01-01

    To investigate the survival, integration, and differentiation of mouse retinal progenitor cells after transplantation to the subretinal space of adult pigs.......To investigate the survival, integration, and differentiation of mouse retinal progenitor cells after transplantation to the subretinal space of adult pigs....

  9. Progenitor cells in arteriosclerosis: good or bad guys?

    Science.gov (United States)

    Campagnolo, Paola; Wong, Mei Mei; Xu, Qingbo

    2011-08-15

    Accumulating evidence indicates that the mobilization and recruitment of circulating or tissue-resident progenitor cells that give rise to endothelial cells (ECs) and smooth muscle cells (SMCs) can participate in atherosclerosis, neointima hyperplasia after arterial injury, and transplant arteriosclerosis. It is believed that endothelial progenitor cells do exist and can repair and rejuvenate the arteries under physiologic conditions; however, they may also contribute to lesion formation by influencing plaque stability in advanced atherosclerotic plaque under specific pathologic conditions. At the same time, smooth muscle progenitors, despite their capacity to expedite lesion formation during restenosis, may serve to promote atherosclerotic plaque stabilization by producing extracellular matrix proteins. This profound evidence provides support to the hypothesis that both endothelial and smooth muscle progenitors may act as a double-edged sword in the pathogenesis of arteriosclerosis. Therefore, the understanding of the regulatory networks that control endothelial and smooth muscle progenitor differentiation is undoubtedly fundamental both for basic research and for improving current therapeutic avenues for atherosclerosis. We update the progress in progenitor cell study related to the development of arteriosclerosis, focusing specifically on the role of progenitor cells in lesion formation and discuss the controversial issues that regard the origins, frequency, and impact of the progenitors in the disease.

  10. Clusters of neural stem/progenitor cells cultured on a soft poly(vinyl alcohol) hydrogel crosslinked by gamma irradiation.

    Science.gov (United States)

    Mori, Hideki; Hara, Masayuki

    2016-05-01

    Neural stem/progenitor cells (NSPCs) in the central nervous system (CNS) have the capacity to self-renew by proliferation and are multipotent, giving rise to neurons, astrocytes, and oligodendrocytes. NSPCs can be amplified in neurosphere suspension cultures for cell transplantation therapy to treat CNS diseases as well as for in vitro pharmacological/toxicological assays; however, these suspension cultures have certain limitations, including the inconvenience of changing the culture medium as well as difficulty of live imaging. In the present study, we prepared a gamma-crosslinked poly(vinyl alcohol) (PVA) hydrogel and assessed its suitability as a substrate for adherent NSPC cultures. Differentiation was determined by evaluating the expression of the markers nestin (progenitors), βIII tubulin (neurons), and glial fibrillary acidic protein and S100β (glia) by immunocytochemistry and quantitative reverse transcriptase PCR. The levels of the marker genes were similar between the two types of culture; although some variability was observed, there were no fold differences in expression. NSPCs adhered to the PVA gel as clusters and grew without differentiating into neurons and glia. The proliferation rate of cells grown on the soft PVA gel [3.75-7.5% (w/v) PVA] was approximately 70% of that of neurospheres in suspension. We conclude that gamma-crosslinked PVA hydrogels can function as a novel scaffold for maintaining adherent NSPCs in an undifferentiated state.

  11. The influence of electric fields on hippocampal neural progenitor cells.

    Science.gov (United States)

    Ariza, Carlos Atico; Fleury, Asha T; Tormos, Christian J; Petruk, Vadim; Chawla, Sagar; Oh, Jisun; Sakaguchi, Donald S; Mallapragada, Surya K

    2010-12-01

    The differentiation and proliferation of neural stem/progenitor cells (NPCs) depend on various in vivo environmental factors or cues, which may include an endogenous electrical field (EF), as observed during nervous system development and repair. In this study, we investigate the morphologic, phenotypic, and mitotic alterations of adult hippocampal NPCs that occur when exposed to two EFs of estimated endogenous strengths. NPCs treated with a 437 mV/mm direct current (DC) EF aligned perpendicularly to the EF vector and had a greater tendency to differentiate into neurons, but not into oligodendrocytes or astrocytes, compared to controls. Furthermore, NPC process growth was promoted perpendicularly and inhibited anodally in the 437 mV/mm DC EF. Yet fewer cells were observed in the DC EF, which in part was due to a decrease in cell viability. The other EF applied was a 46 mV/mm alternating current (AC) EF. However, the 46 mV/mm AC EF showed no major differences in alignment or differentiation, compared to control conditions. For both EF treatments, the percent of mitotic cells during the last 14 h of the experiment were statistically similar to controls. Reported here, to our knowledge, is the first evidence of adult NPC differentiation affected in an EF in vitro. Further investigation and application of EFs on stem cells is warranted to elucidate the utility of EFs to control phenotypic behavior. With progress, the use of EFs may be engineered to control differentiation and target the growth of transplanted cells in a stem cell-based therapy to treat nervous system disorders.

  12. Müller glia: Stem cells for generation and regeneration of retinal neurons in teleost fish.

    Science.gov (United States)

    Lenkowski, Jenny R; Raymond, Pamela A

    2014-05-01

    Adult zebrafish generate new neurons in the brain and retina throughout life. Growth-related neurogenesis allows a vigorous regenerative response to damage, and fish can regenerate retinal neurons, including photoreceptors, and restore functional vision following photic, chemical, or mechanical destruction of the retina. Müller glial cells in fish function as radial-glial-like neural stem cells. During adult growth, Müller glial nuclei undergo sporadic, asymmetric, self-renewing mitotic divisions in the inner nuclear layer to generate a rod progenitor that migrates along the radial fiber of the Müller glia into the outer nuclear layer, proliferates, and differentiates exclusively into rod photoreceptors. When retinal neurons are destroyed, Müller glia in the immediate vicinity of the damage partially and transiently dedifferentiate, re-express retinal progenitor and stem cell markers, re-enter the cell cycle, undergo interkinetic nuclear migration (characteristic of neuroepithelial cells), and divide once in an asymmetric, self-renewing division to generate a retinal progenitor. This daughter cell proliferates rapidly to form a compact neurogenic cluster surrounding the Müller glia; these multipotent retinal progenitors then migrate along the radial fiber to the appropriate lamina to replace missing retinal neurons. Some aspects of the injury-response in fish Müller glia resemble gliosis as observed in mammals, and mammalian Müller glia exhibit some neurogenic properties, indicative of a latent ability to regenerate retinal neurons. Understanding the specific properties of fish Müller glia that facilitate their robust capacity to generate retinal neurons will inform and inspire new clinical approaches for treating blindness and visual loss with regenerative medicine.

  13. Mast cell progenitors: origin, development and migration to tissues.

    Science.gov (United States)

    Dahlin, Joakim S; Hallgren, Jenny

    2015-01-01

    Mast cells in tissues are developed from mast cell progenitors emerging from the bone marrow in a process highly regulated by transcription factors. Through the advancement of the multicolor flow cytometry technique, the mast cell progenitor population in the mouse has been characterized in terms of surface markers. However, only cell populations with enriched mast cell capability have been described in human. In naïve mice, the peripheral tissues have a constitutive pool of mast cell progenitors. Upon infections in the gut and in allergic inflammation in the lung, the local mast cell progenitor numbers increase tremendously. This review focuses on the origin and development of mast cell progenitors. Furthermore, the evidences for cells and molecules that govern the migration of these cells in mice in vivo are described.

  14. Effect of human neural progenitor cells on injured spinal cord

    Institute of Scientific and Technical Information of China (English)

    XU Guang-hui; BAI Jin-zhu; CAI Qin-lin; LI Xiao-xia; LI Ling-song; SHEN Li

    2005-01-01

    Objective: To study whether human neural progenitor cells can differentiate into neural cells in vivo and improve the recovery of injured spinal cord in rats.Methods: Human neural progenitor cells were transplanted into the injured spinal cord and the functional recovery of the rats with spinal cord contusion injury was evaluated with Basso-Beattie-Bresnahan (BBB) locomotor scale and motor evoked potentials. Additionally, the differentiation of human neural progenitor cells was shown by immunocytochemistry.Results: Human neural progenitor cells developed into functional cells in the injured spinal cord and improved the recovery of injured spinal cord in both locomotor scores and electrophysiological parameters in rats.Conclusions: Human neural progenitor cells can treat injured spinal cord, which may provide a new cell source for research of clinical application.

  15. Hepatic progenitor cells in human liver tumor development

    Institute of Scientific and Technical Information of China (English)

    Louis Libbrecht

    2006-01-01

    In recent years, the results of several studies suggest that human liver tumors can be derived from hepatic progenitor cells rather than from mature cell types.The available data indeed strongly suggest that most combined hepatocellular-cholangiocarcinomas arise from hepatic progenitor cells that retained their potential to differentiate into the hepatocytic and biliary lineages.Hepatic progenitor cells could also be the basis for some hepatocellular carcinomas and hepatocellular adenomas, although it is very difficult to determine the origin of an individual hepatocellular carcinoma. There is currently not enough data to make statements regarding a hepatic progenitor cell origin of cholangiocarcinoma.The presence of hepatic progenitor cell markers and the presence and extent of the cholangiocellular component are factors that are related to the prognosis of hepatocellular carcinomas and combined hepatocellularcholangiocarcinomas, respectively.

  16. Conditional induction of Math1 specifies embryonic stem cells to cerebellar granule neuron lineage and promotes differentiation into mature granule neurons.

    Science.gov (United States)

    Srivastava, Rupali; Kumar, Manoj; Peineau, Stéphane; Csaba, Zsolt; Mani, Shyamala; Gressens, Pierre; El Ghouzzi, Vincent

    2013-04-01

    Directing differentiation of embryonic stem cells (ESCs) to specific neuronal subtype is critical for modeling disease pathology in vitro. An attractive means of action would be to combine regulatory differentiation factors and extrinsic inductive signals added to the culture medium. In this study, we have generated mature cerebellar granule neurons by combining a temporally controlled transient expression of Math1, a master gene in granule neuron differentiation, with inductive extrinsic factors involved in cerebellar development. Using a Tetracyclin-On transactivation system, we overexpressed Math1 at various stages of ESCs differentiation and found that the yield of progenitors was considerably increased when Math1 was induced during embryonic body stage. Math1 triggered expression of Mbh1 and Mbh2, two target genes directly involved in granule neuron precursor formation and strong expression of early cerebellar territory markers En1 and NeuroD1. Three weeks after induction, we observed a decrease in the number of glial cells and an increase in that of neurons albeit still immature. Combining Math1 induction with extrinsic factors specifically increased the number of neurons that expressed Pde1c, Zic1, and GABAα6R characteristic of mature granule neurons, formed "T-shaped" axons typical of granule neurons, and generated synaptic contacts and action potentials in vitro. Finally, in vivo implantation of Math1-induced progenitors into young adult mice resulted in cell migration and settling of newly generated neurons in the cerebellum. These results show that conditional induction of Math1 drives ESCs toward the cerebellar fate and indicate that acting on both intrinsic and extrinsic factors is a powerful means to modulate ESCs differentiation and maturation into a specific neuronal lineage.

  17. Running rescues defective adult neurogenesis by shortening the length of the cell cycle of neural stem and progenitor cells.

    Science.gov (United States)

    Farioli-Vecchioli, Stefano; Mattera, Andrea; Micheli, Laura; Ceccarelli, Manuela; Leonardi, Luca; Saraulli, Daniele; Costanzi, Marco; Cestari, Vincenzo; Rouault, Jean-Pierre; Tirone, Felice

    2014-07-01

    Physical exercise increases the generation of new neurons in adult neurogenesis. However, only few studies have investigated the beneficial effects of physical exercise in paradigms of impaired neurogenesis. Here, we demonstrate that running fully reverses the deficient adult neurogenesis within the hippocampus and subventricular zone of the lateral ventricle, observed in mice lacking the antiproliferative gene Btg1. We also evaluated for the first time how running influences the cell cycle kinetics of stem and precursor subpopulations of wild-type and Btg1-null mice, using a new method to determine the cell cycle length. Our data show that in wild-type mice running leads to a cell cycle shortening only of NeuroD1-positive progenitor cells. In contrast, in Btg1-null mice, physical exercise fully reactivates the defective hippocampal neurogenesis, by shortening the S-phase length and the overall cell cycle duration of both neural stem (glial fibrillary acidic protein(+) and Sox2(+)) and progenitor (NeuroD1(+)) cells. These events are sufficient and necessary to reactivate the hyperproliferation observed in Btg1-null early-postnatal mice and to expand the pool of adult neural stem and progenitor cells. Such a sustained increase of cell proliferation in Btg1-null mice after running provides a long-lasting increment of proliferation, differentiation, and production of newborn neurons, which rescues the impaired pattern separation previously identified in Btg1-null mice. This study shows that running positively affects the cell cycle kinetics of specific subpopulations of newly generated neurons and suggests that the plasticity of neural stem cells without cell cycle inhibitory control is reactivated by running, with implications for the long-term modulation of neurogenesis.

  18. Folic acid supplementation changes the fate of neural progenitors in mouse embryos of hyperglycemic and diabetic pregnancy.

    Science.gov (United States)

    Yuan, Qiuhuan; Zhao, Shidou; Liu, Shangming; Zhang, Yanmin; Fu, Jie; Wang, Fuwu; Liu, Qian; Ling, Eng-Ang; Hao, Aijun

    2013-07-01

    Folic acid has been shown to decrease the incidence of neural tube defects (NTDs) in normal and hyperglycemic conditions, but the influence of folic acid on the development of central nervous system is not fully understood. Here, we aimed to explore the effects of folic acid, especially high dose of folic acid, on the characteristics of neural progenitors in embryos of hyperglycemic and diabetic mouse. Hyperglycemic and diabetic pregnant mice were given 3 mg/kg or 15 mg/kg folic acid from embryonic day 0.5 (E0.5) and were euthanased on E11.5, E13.5 or E18.5. The incidence of NTDs at E13.5 was counted. The proliferation, apoptosis and differentiation of neural progenitors and neuronal migration were determined using BrdU incorporation assay, TUNEL assay, immunofluorescence, Western blot and real-time reverse transcriptase polymerase chain reaction. Both normal and high doses of folic acid decreased the incidence of NTDs, promoted proliferation and reduced apoptosis of neuroepithelial cells in embryos of hyperglycemic and diabetic mice. Importantly, folic acid, especially at high dose, might affect the premature differentiation of neural progenitors in embryos of hyperglycemic and diabetic pregnancy. This may be attributed to changes of messenger RNA expression levels of some basic-helix-loop-helix transcription factors. In addition, folic acid might be involved in regulating neuronal migration in embryos of hyperglycemic and diabetic pregnancy. These findings suggest that periconceptional supplementation of folic acid, especially at high dose, may be a double-edged sword because it may result in undesirable outcomes affecting both the neuronal and glial differentiation in hyperglycemic and diabetic pregnancy.

  19. The Specification and Maturation of Nociceptive Neurons from Human Embryonic Stem Cells.

    Science.gov (United States)

    Boisvert, Erin M; Engle, Sandra J; Hallowell, Shawn E; Liu, Ping; Wang, Zhao-Wen; Li, Xue-Jun

    2015-11-19

    Nociceptive neurons play an essential role in pain sensation by transmitting painful stimuli to the central nervous system. However, investigations of nociceptive neuron biology have been hampered by the lack of accessibility of human nociceptive neurons. Here, we describe a system for efficiently guiding human embryonic stem cells into nociceptive neurons by first inducing these cells to the neural lineage. Subsequent addition of retinoic acid and BMP4 at specific time points and concentrations yielded a high population of neural crest progenitor cells (AP2α(+), P75(+)), which further differentiated into nociceptive neurons (TRKA(+), Nav1.7(+), P2X3(+)). The overexpression of Neurogenin 1 (Neurog1) promoted the neurons to express genes related to sensory neurons (Peripherin, TrkA) and to further mature into TRPV1(+) nociceptive neurons. Importantly, the overexpression of Neurog1 increased the response of these neurons to capsaicin stimulation, a hallmark of mature functional nociceptive neurons. Taken together, this study reveals the important role that Neurog1 plays in generating functional human nociceptive neurons.

  20. Analysis of neural progenitors from embryogenesis to juvenile adult in Xenopus laevis reveals biphasic neurogenesis and continuous lengthening of the cell cycle

    Directory of Open Access Journals (Sweden)

    Raphaël Thuret

    2015-12-01

    Full Text Available Xenopus laevis is a prominent model system for studying neural development, but our understanding of the long-term temporal dynamics of neurogenesis remains incomplete. Here, we present the first continuous description of neurogenesis in X. laevis, covering the entire period of development from the specification of neural ectoderm during gastrulation to juvenile frog. We have used molecular markers to identify progenitors and neurons, short-term bromodeoxyuridine (BrdU incorporation to map the generation of newborn neurons and dual pulse S-phase labelling to characterise changes in their cell cycle length. Our study revealed the persistence of Sox3-positive progenitor cells from the earliest stages of neural development through to the juvenile adult. Two periods of intense neuronal generation were observed, confirming the existence of primary and secondary waves of neurogenesis, punctuated by a period of quiescence before metamorphosis and culminating in another period of quiescence in the young adult. Analysis of multiple parameters indicates that neural progenitors alternate between global phases of differentiation and amplification and that, regardless of their behaviour, their cell cycle lengthens monotonically during development, at least at the population level.

  1. SSEA-4 and YKL-40 positive progenitor subtypes in the subventricular zone of developing human neocortex.

    Science.gov (United States)

    Brøchner, Christian B; Møllgård, Kjeld

    2016-01-01

    The glycosphingolipid SSEA-4 and the glycoprotein YKL-40 have both been associated with human embryonic and neural stem cell differentiation. We investigated the distribution of SSEA-4 and YKL-40 positive cells in proliferative zones of human fetal forebrain using immunohistochemistry and double-labeling immunofluorescence. A few small rounded SSEA-4 and YKL-40 labeled cells were present in the radial glial BLBP positive proliferative zones adjacent to the lateral ganglionic eminence from 12th week post conception. With increasing age, a similarly stained cell population appeared more widespread in the subventricular zone. At midgestation, the entire subventricular zone showed patches of SSEA-4, YKL-40, and BLBP positive cells. Co-labeling with markers for radial glial cells (RGCs) and neuronal, glial, and microglial markers tested the lineage identity of this subpopulation of radial glial descendants. Adjacent to the ventricular zone, a minor fraction showed overlap with GFAP but not with nestin, Olig2, NG2, or S100. No co-localization was found with neuronal markers NeuN, calbindin, DCX or with markers for microglial cells (Iba-1, CD68). Moreover, the SSEA-4 and YKL-40 positive cell population in subventricular zone was largely devoid of Tbr2, a marker for intermediate neuronal progenitor cells descending from RGCs. YKL-40 has recently been found in astrocytes in the neuron-free fimbria, and both SSEA-4 and YKL-40 are present in malignant astroglial brain tumors. We suggest that the population of cells characterized by immunohistochemical combination of antibodies against SSEA-4 and YKL-40 and devoid of neuronal and microglial markers represent a yet unexplored astrogenic lineage illustrating the complexity of astroglial development.

  2. General artificial neuron

    Science.gov (United States)

    Degeratu, Vasile; Schiopu, Paul; Degeratu, Stefania

    2007-05-01

    In this paper the authors present a model of artificial neuron named the general artificial neuron. Depending on application this neuron can change self number of inputs, the type of inputs (from excitatory in inhibitory or vice versa), the synaptic weights, the threshold, the type of intensifying functions. It is achieved into optoelectronic technology. Also, into optoelectronic technology a model of general McCulloch-Pitts neuron is showed. The advantages of these neurons are very high because we have to solve different applications with the same neural network, achieved from these neurons, named general neural network.

  3. Purification of functional human ES and iPSC-derived midbrain dopaminergic progenitors using LRTM1

    Science.gov (United States)

    Samata, Bumpei; Doi, Daisuke; Nishimura, Kaneyasu; Kikuchi, Tetsuhiro; Watanabe, Akira; Sakamoto, Yoshimasa; Kakuta, Jungo; Ono, Yuichi; Takahashi, Jun

    2016-01-01

    Human induced pluripotent stem cells (iPSCs) can provide a promising source of midbrain dopaminergic (mDA) neurons for cell replacement therapy for Parkinson's disease (PD). However, iPSC-derived donor cells inevitably contain tumorigenic or inappropriate cells. To eliminate these unwanted cells, cell sorting using antibodies for specific markers such as CORIN or ALCAM has been developed, but neither marker is specific for ventral midbrain. Here we employ a double selection strategy for cells expressing both CORIN and LMX1A::GFP, and report a cell surface marker to enrich mDA progenitors, LRTM1. When transplanted into 6-OHDA-lesioned rats, human iPSC-derived LRTM1+ cells survive and differentiate into mDA neurons in vivo, resulting in a significant improvement in motor behaviour without tumour formation. In addition, there was marked survival of mDA neurons following transplantation of LRTM1+ cells into the brain of an MPTP-treated monkey. Thus, LRTM1 may provide a tool for efficient and safe cell therapy for PD patients. PMID:27739432

  4. Injury-induced neurogenesis: consideration of resident microglia as supportive of neural progenitor cells.

    Science.gov (United States)

    McPherson, Christopher A; Kraft, Andrew D; Harry, G Jean

    2011-02-01

    The induction of neurogenesis in the adult subgranular zone (SGZ) by injury is often accompanied by changes in the extracellular environment that can have significant impacts on neural progenitor cells (NPCs). We examined the induction of neurogenesis in the SGZ at 72 h following an injection of the hippocampal toxicant, trimethyltin (TMT; 2 mg/kg, ip) inducing apoptosis in dentate granule neurons. BrdU+ incorporation during the active period of neuronal death indicated NPC proliferation and migration of newly generated cells into the granule cell layer (GCL). BrdU+ cells were transiently in contact with process bearing microglia within the inner SGZ layer. Contact with GFAP+ astrocyte processes occurred once cells were within the GCL. A small percentage of the BrdU+ cells within the SGZ region showed immunoreactivity for tumor necrosis factor (TNF) p75 receptor (TNFp75R). In mice deficient for TNFp75R, TMT injection produced an equivalent level of dentate granule cell death however; BrdU+ cells were localized at the SGZ as compared to the presence of cells within the GCL in the WT mice dosed with TMT. These data suggest that cells generated by NPCs in the SGZ induced with a focal lesion to the dentate granule neurons of adolescent mice maintain the capacity to utilize the neuroinflammation and microglia responses within their environment for migration into the GCL.

  5. Migration and differentiation of neural progenitor cells after recurrent laryngeal nerve avulsion in rats.

    Directory of Open Access Journals (Sweden)

    Wan Zhao

    Full Text Available To investigate migration and differentiation of neural progenitor cells (NPCs from the ependymal layer to the nucleus ambiguus (NA after recurrent laryngeal nerve (RLN avulsion. All of the animals received a CM-DiI injection in the left lateral ventricle. Forty-five adult rats were subjected to a left RLN avulsion injury, and nine rats were used as controls. 5-Bromo-2-deoxyuridine (BrdU was injected intraperitoneally. Immunohistochemical analyses were performed in the brain stems at different time points after RLN injury. After RLN avulsion, the CM-DiI+ NPCs from the ependymal layer migrated to the lesioned NA. CM-DiI+/GFAP+ astrocytes, CM-DiI+/DCX+ neuroblasts and CM-DiI+/NeuN+ neurons were observed in the migratory stream. However, the ipsilateral NA included only CM-DiI+ astrocytes, not newborn neurons. After RLN avulsion, the NPCs in the ependymal layer of the 4th ventricle or central canal attempt to restore the damaged NA. We first confirm that the migratory stream includes both neurons and glia differentiated from the NPCs. However, only differentiated astrocytes are successfully incorporated into the NA. The presence of both cell types in the migratory process may play a role in repairing RLN injuries.

  6. Migration and differentiation of neural progenitor cells after recurrent laryngeal nerve avulsion in rats.

    Science.gov (United States)

    Zhao, Wan; Xu, Wen

    2014-01-01

    To investigate migration and differentiation of neural progenitor cells (NPCs) from the ependymal layer to the nucleus ambiguus (NA) after recurrent laryngeal nerve (RLN) avulsion. All of the animals received a CM-DiI injection in the left lateral ventricle. Forty-five adult rats were subjected to a left RLN avulsion injury, and nine rats were used as controls. 5-Bromo-2-deoxyuridine (BrdU) was injected intraperitoneally. Immunohistochemical analyses were performed in the brain stems at different time points after RLN injury. After RLN avulsion, the CM-DiI+ NPCs from the ependymal layer migrated to the lesioned NA. CM-DiI+/GFAP+ astrocytes, CM-DiI+/DCX+ neuroblasts and CM-DiI+/NeuN+ neurons were observed in the migratory stream. However, the ipsilateral NA included only CM-DiI+ astrocytes, not newborn neurons. After RLN avulsion, the NPCs in the ependymal layer of the 4th ventricle or central canal attempt to restore the damaged NA. We first confirm that the migratory stream includes both neurons and glia differentiated from the NPCs. However, only differentiated astrocytes are successfully incorporated into the NA. The presence of both cell types in the migratory process may play a role in repairing RLN injuries.

  7. Protection of visual functions by human neural progenitors in a rat model of retinal disease.

    Directory of Open Access Journals (Sweden)

    David M Gamm

    Full Text Available BACKGROUND: A promising clinical application for stem and progenitor cell transplantation is in rescue therapy for degenerative diseases. This strategy seeks to preserve rather than restore host tissue function by taking advantage of unique properties often displayed by these versatile cells. In studies using different neurodegenerative disease models, transplanted human neural progenitor cells (hNPC protected dying host neurons within both the brain and spinal cord. Based on these reports, we explored the potential of hNPC transplantation to rescue visual function in an animal model of retinal degeneration, the Royal College of Surgeons rat. METHODOLOGY/PRINCIPAL FINDINGS: Animals received unilateral subretinal injections of hNPC or medium alone at an age preceding major photoreceptor loss. Principal outcomes were quantified using electroretinography, visual acuity measurements and luminance threshold recordings from the superior colliculus. At 90-100 days postnatal, a time point when untreated rats exhibit little or no retinal or visual function, hNPC-treated eyes retained substantial retinal electrical activity and visual field with near-normal visual acuity. Functional efficacy was further enhanced when hNPC were genetically engineered to secrete glial cell line-derived neurotrophic factor. Histological examination at 150 days postnatal showed hNPC had formed a nearly continuous pigmented layer between the neural retina and retinal pigment epithelium, as well as distributed within the inner retina. A concomitant preservation of host cone photoreceptors was also observed. CONCLUSIONS/SIGNIFICANCE: Wild type and genetically modified human neural progenitor cells survive for prolonged periods, migrate extensively, secrete growth factors and rescue visual functions following subretinal transplantation in the Royal College of Surgeons rat. These results underscore the potential therapeutic utility of hNPC in the treatment of retinal degenerative

  8. Roles of CDX2 and EOMES in human induced trophoblast progenitor cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ying, E-mail: ying.chen@hc.msu.edu [Department of Obstetrics, Gynecology and Reproductive Biology, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503 (United States); Wang, Kai [Department of Obstetrics, Gynecology and Reproductive Biology, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503 (United States); Gong, Yun Guo; Khoo, Sok Kean [Genomic Microarray Core Facility, Van Andel Research Institute, Grand Rapids, MI 49503 (United States); Leach, Richard, E-mail: Richard.Leach@hc.msu.edu [Department of Obstetrics, Gynecology and Reproductive Biology, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503 (United States); Department of Obstetrics, Gynecology and Women’s Health, Spectrum Health Medical Group, Grand Rapids, MI 49503 (United States)

    2013-02-08

    Highlights: ► CDX2 and EOMES play critical roles in human induced trophoblast progenitors (iTP). ► iTP cells directly transformed from fibroblasts. ► Differentiation of iTP cells into extravillous trophoblasts and syncytiotrophoblasts. -- Abstract: Abnormal trophoblast lineage proliferation and differentiation in early pregnancy have been associated with the pathogenesis of placenta diseases of pregnancy. However, there is still a gap in understanding the molecular mechanisms of early placental development due to the limited primary trophoblast cultures and fidelity of immortalized trophoblast lines. Trophoblasts stem (TS) cells, an in vitro model of trophectoderm that can differentiate into syncytiotrophoblasts and extravillous trophoblasts, can be an attractive tool for early pregnancy research. TS cells are well established in mouse but not in humans due to insufficient knowledge of which trophoblast lineage-specific transcription factors are involved in human trophectoderm (TE) proliferation and differentiation. Here, we applied induced pluripotent stem cell technique to investigate the human trophoblast lineage-specific transcription factors. We established human induced trophoblast progenitor (iTP) cells by direct reprogramming the fibroblasts with a pool of mouse trophoblast lineage-specific transcription factors consisting of CDX2, EOMES, and ELF5. The human iTP cells exhibit epithelial morphology and can be maintained in vitro for more than 2 months. Gene expression profile of these cells was tightly clustered with human trophectoderm but not with human neuron progenitor cells, mesenchymal stem cells, or endoderm cells. These cells are capable of differentiating into cells with an invasive capacity, suggesting extravillous trophoblasts. They also form multi-nucleated cells which secrete human chorionic gonadotropin and estradiol, consistent with a syncytiotrophoblast phenotype. Our results provide the evidence that transcription factors CDX2 and

  9. Cardiac Progenitor Cell Extraction from Human Auricles

    KAUST Repository

    Di Nardo, Paolo

    2017-02-22

    For many years, myocardial tissue has been considered terminally differentiated and, thus, incapable of regenerating. Recent studies have shown, instead, that cardiomyocytes, at least in part, are slowly substituted by new cells originating by precursor cells mostly embedded into the heart apex and in the atria. We have shown that an elective region of progenitor cell embedding is represented by the auricles, non-contractile atria appendages that can be easily sampled without harming the patient. The protocol here reported describes how from auricles a population of multipotent, cardiogenic cells can be isolated, cultured, and differentiated. Further studies are needed to fully exploit this cell population, but, sampling auricles, it could be possible to treat cardiac patients using their own cells circumventing rejection or organ shortage limitations.

  10. PET imaging of adoptive progenitor cell therapies.

    Energy Technology Data Exchange (ETDEWEB)

    Gelovani, Juri G.

    2008-05-13

    Objectives. The overall objective of this application is to develop novel technologies for non-invasive imaging of adoptive stem cell-based therapies with positron emission tomography (PET) that would be applicable to human patients. To achieve this objective, stem cells will be genetically labeled with a PET-reporter gene and repetitively imaged to assess their distribution, migration, differentiation, and persistence using a radiolabeled reporter probe. This new imaging technology will be tested in adoptive progenitor cell-based therapy models in animals, including: delivery pro-apoptotic genes to tumors, and T-cell reconstitution for immunostimulatory therapy during allogeneic bone marrow progenitor cell transplantation. Technical and Scientific Merits. Non-invasive whole body imaging would significantly aid in the development and clinical implementation of various adoptive progenitor cell-based therapies by providing the means for non-invasive monitoring of the fate of injected progenitor cells over a long period of observation. The proposed imaging approaches could help to address several questions related to stem cell migration and homing, their long-term viability, and their subsequent differentiation. The ability to image these processes non-invasively in 3D and repetitively over a long period of time is very important and will help the development and clinical application of various strategies to control and direct stem cell migration and differentiation. Approach to accomplish the work. Stem cells will be genetically with a reporter gene which will allow for repetitive non-invasive “tracking” of the migration and localization of genetically labeled stem cells and their progeny. This is a radically new approach that is being developed for future human applications and should allow for a long term (many years) repetitive imaging of the fate of tissues that develop from the transplanted stem cells. Why the approach is appropriate. The novel approach to

  11. New approaches to SNe Ia progenitors

    CERN Document Server

    Ruiz-Lapuente, Pilar

    2014-01-01

    Although Type Ia supernovae (SNe Ia) are a major tool in cosmology and play a key role in the chemical evolution of galaxies, the nature of their progenitor systems (apart from the fact that they must be close binaries containing at least one white dwarf) remains largely unknown. In the last decade, considerable efforts have been made, both observationally and theoretically, to solve this problem. Observations have, however, revealed a previously unsuspected variety of events, ranging from very underluminous outbursts to clearly overluminous ones, and spanning a range well outside the peak luminosity--decline rate of the light curve relationship, used to make calibrated candles of the SNe Ia. On the theoretical side, new explosion scenarios, such as violent mergings of pairs of white dwarfs, have been explored. We review those recent developments, emphasizing the new observational findings, but also trying to tie them to the different scenarios and explosion mechanisms proposed thus far.

  12. Juvenil neuronal ceroid lipofuscinosis

    DEFF Research Database (Denmark)

    Ostergaard, J R; Hertz, Jens Michael

    1998-01-01

    Neuronal ceroid-lipofuscinosis is a group of neurodegenerative diseases which are characterized by an abnormal accumulation of lipopigment in neuronal and extraneuronal cells. The diseases can be differentiated into several subgroups according to age of onset, the clinical picture...

  13. Thrombopoietin is a growth factor for rat hepatic progenitors.

    Science.gov (United States)

    Schmelzer, Eva; Deiwick, Andrea; Bruns, Helge; Fiegel, Henning C; Bader, Augustinus

    2008-03-01

    The liver is the primary site of hematopoiesis during fetal development; it has been shown that thrombopoietin (TPO) produced by the liver during fetal development is a major regulator of megakaryocytopoiesis. As maximum liver growth and hematopoiesis occur simultaneously, we hypothesized that TPO may act as a growth factor for hepatic progenitors. Therefore, the influence of TPO on the proliferation of fetal hepatic progenitors in vitro compared with that of adult hepatocytes was analyzed. The expression of the TPO receptor, c-mpl, was investigated in fetal and adult liver. Cell proliferation was measured by bromodeoxyuridine incorporation and total cell counts. TPO and c-mpl gene expression was investigated by reverse transcription polymerase chain reaction. The cell surface expression of c-mpl was analyzed in fetal and adult human liver by immunohistochemistry. Hepatic progenitors of fetal and adult liver but not hepatocytes expressed the TPO receptor, c-mpl, on the cell surface. Fetal hepatic progenitors expressed mRNA for TPO and its receptor. TPO stimulated cell proliferation and increased cell numbers of cultured rat fetal hepatic progenitors but not adult hepatocytes. We conclude that TPO acts in addition to its known role in megakaryocytopoiesis as a growth factor for hepatic progenitors but not hepatocytes in vitro; thus, TPO represents a growth factor for hepatic progenitors during fetal liver development.

  14. The multipolar stage and disruptions in neuronal migration.

    Science.gov (United States)

    LoTurco, Joseph J; Bai, Jilin

    2006-07-01

    The genetic basis is now known for several disorders of neuronal migration in the developing cerebral cortex. Identification of the cellular processes mediated by the implicated genes is revealing crucial stages of neuronal migration and has the potential to reveal common cellular causes of neuronal migration disorders. We hypothesize that a newly recognized morphological stage of neuronal migration, the multipolar stage, is vulnerable and is disrupted in several disorders of neocortical development. The multipolar stage occurs as bipolar progenitor cells become radially migrating neurons. Several studies using in utero electroporation and RNAi have revealed that transition out of the multipolar stage depends on the function of filamin A, LIS1 and DCX. Mutations in the genes encoding these proteins in humans cause distinct neuronal migration disorders, including periventricular nodular heterotopia, subcortical band heterotopia and lissencephaly. The multipolar stage therefore seems to be a critical point of migration control and a vulnerable target for disruption of neocortical development. This review is part of the INMED/TINS special issue "Nature and nurture in brain development and neurological disorders", based on presentations at the annual INMED/TINS symposium (http://inmednet.com/).

  15. TALE-class homeodomain transcription factors, homothorax and extradenticle, control dendritic and axonal targeting of olfactory projection neurons in the Drosophila brain.

    Science.gov (United States)

    Ando, Mai; Totani, Yoko; Walldorf, Uwe; Furukubo-Tokunaga, Katsuo

    2011-10-01

    Precise neuronal connectivity in the nervous system depends on specific axonal and dendritic targeting of individual neurons. In the Drosophila brain, olfactory projection neurons convey odor information from the antennal lobe to higher order brain centers such as the mushroom body and the lateral horn. Here, we show that Homothorax (Hth), a TALE-class homeodomain transcription factor, is expressed in many of the antennal lobe neurons including projection neurons and local interneurons. In addition, HTH is expressed in the progenitors of the olfactory projection neurons, and the activity of hth is required for the generation of the lateral but not for the anterodorsal and ventral lineages. MARCM analyses show that the hth is essential for correct dendritic targeting of projection neurons in the antennal lobe. Moreover, the activity of hth is required for axonal fasciculation, correct routing and terminal branching of the projection neurons. We also show that another TALE-class homeodomain protein, Extradenticle (Exd), is required for the dendritic and axonal development of projection neurons. Mutation of exd causes projection neuron defects that are reminiscent of the phenotypes caused by the loss of the hth activity. Double immunostaining experiments show that Hth and Exd are coexpressed in olfactory projection neurons and their progenitors, and that the expressions of Hth and Exd require the activity of each other gene. These results thus demonstrate the functional importance of the TALE-class homeodomain proteins in cell-type specification and precise wiring of the Drosophila olfactory network.

  16. Interneurons and oligodendrocyte progenitors form a structured synaptic network in the developing neocortex.

    Science.gov (United States)

    Orduz, David; Maldonado, Paloma P; Balia, Maddalena; Vélez-Fort, Mateo; de Sars, Vincent; Yanagawa, Yuchio; Emiliani, Valentina; Angulo, Maria Cecilia

    2015-04-22

    NG2 cells, oligodendrocyte progenitors, receive a major synaptic input from interneurons in the developing neocortex. It is presumed that these precursors integrate cortical networks where they act as sensors of neuronal activity. We show that NG2 cells of the developing somatosensory cortex form a transient and structured synaptic network with interneurons that follows its own rules of connectivity. Fast-spiking interneurons, highly connected to NG2 cells, target proximal subcellular domains containing GABAA receptors with γ2 subunits. Conversely, non-fast-spiking interneurons, poorly connected with these progenitors, target distal sites lacking this subunit. In the network, interneuron-NG2 cell connectivity maps exhibit a local spatial arrangement reflecting innervation only by the nearest interneurons. This microcircuit architecture shows a connectivity peak at PN10, coinciding with a switch to massive oligodendrocyte differentiation. Hence, GABAergic innervation of NG2 cells is temporally and spatially regulated from the subcellular to the network level in coordination with the onset of oligodendrogenesis.

  17. Feline Neural Progenitor Cells I: Long-Term Expansion under Defined Culture Conditions

    Directory of Open Access Journals (Sweden)

    Jing Yang

    2012-01-01

    Full Text Available Neural progenitor cells (NPCs of feline origin (cNPCs have demonstrated utility in transplantation experiments, yet are difficult to grow in culture beyond the 1 month time frame. Here we use an enriched, serum-free base medium (Ultraculture and report the successful long-term propagation of these cells. Primary cultures were derived from fetal brain tissue and passaged in DMEM/F12-based or Ultraculture-based proliferation media, both in the presence of EGF + bFGF. Cells in standard DMEM/F12-based medium ceased to proliferate by 1-month, whereas the cells in the Ultraculture-based medium continued to grow for at least 5 months (end of study with no evidence of senescence. The Ultraculture-based cultures expressed lower levels of progenitor and lineage-associated markers under proliferation conditions but retained multipotency as evidenced by the ability to differentiate into neurons and glia following growth factor removal in the presence of FBS. Importantly, later passage cNPCs did not develop chromosomal aberrations.

  18. Stress, Glucocorticoid Hormones and Hippocampal Neural Progenitor Cells: Implications to Mood Disorders

    Directory of Open Access Journals (Sweden)

    Tomoshige eKino

    2015-08-01

    Full Text Available The hypothalamic-pituitary-adrenal (HPA axis and its end-effectors glucocorticoid hormones play central roles in the adaptive response to numerous stressors that can be either internal or external. Thus, this system has a strong impact on the brain hippocampus and its major functions, such as cognition, memory as well as behavior and mood. The hippocampal area of the adult brain contains neural stem cells or more committed neural progenitor cells, which retain throughout the human life the ability of self-renewal and to differentiate into multiple neural cell lineages, such as neurons, astrocytes and oligodendrocytes. Importantly, these characteristic cells contribute significantly to the above-indicated functions of the hippocampus, while various stressors and glucocorticoids influence proliferation, differentiation and fate of these cells. This review offers an overview of the current understanding on the interactions between the HPA axis/glucocorticoid stress-responsive system and hippocampal neural progenitor cells by focusing on the actions of glucocorticoids. Also addressed is a further discussion on the implications of such interactions to the pathophysiology of mood disorders.

  19. NEURON and Python

    OpenAIRE

    Michael Hines; Davison, Andrew P.; Eilif Muller

    2009-01-01

    The NEURON simulation program now allows Python to be used, alone or in combination with NEURON's traditional Hoc interpreter. Adding Python to NEURON has the immediate benefit of making available a very extensive suite of analysis tools written for engineering and science. It also catalyzes NEURON software development by offering users a modern programming tool that is recognized for its flexibility and power to create and maintain complex programs. At the same time, nothing is lost because ...

  20. Transcriptional changes during neuronal death and replacement in the olfactory epithelium.

    Science.gov (United States)

    Shetty, Ranjit S; Bose, Soma C; Nickell, Melissa D; McIntyre, Jeremy C; Hardin, Debra H; Harris, Andrew M; McClintock, Timothy S

    2005-12-01

    The olfactory epithelium has the unusual ability to replace its neurons.We forced replacement of mouse olfactory sensory neurons by bulbectomy. Microarray, bioinformatics, and in situ hybridization techniques detected a rapid shift in favor of pro-apoptotic proteins, a progressive immune response by macrophages and dendritic cells, and identified or predicted 439 mRNAs enriched in olfactory sensory neurons, including gene silencing factors and sperm flagellar proteins. Transcripts encoding cell cycle regulators, axonogenesis proteins, and transcription factors and signaling proteins that promote proliferation and differentiation were increased at 5-7 days after bulbectomy and were expressed by basal progenitor cells or immature neurons. The transcription factors included Nhlhl, Hes6, Lmycl, c-Myc, Mxd4, Idl,Nmycl, Cited2, c-Myb, Mybll, Tead2, Dpl, Gata2, Lmol, and Soxll. The data reveal significant similarities with embryonic neurogenesis and make several mechanistic predictions, including the roles of the transcription factors in the olfactory sensory neuron lineage.

  1. MRI visualization of endogenous neural progenitor cell migration along the RMS in the adult mouse brain

    DEFF Research Database (Denmark)

    Vreys, Ruth; Vande Velde, Greetje; Krylychkina, Olga

    2010-01-01

    The adult rodent brain contains neural progenitor cells (NPCs), generated in the subventricular zone (SVZ), which migrate along the rostral migratory stream (RMS) towards the olfactory bulb (OB) where they differentiate into neurons. The aim of this study was to visualize endogenous NPC migration...... along the RMS with magnetic resonance imaging (MRI) in adult healthy mice. We evaluated various in situ (in vivo) labeling approaches using micron-sized iron oxide particles (MPIOs) on their efficiency to label endogenous NPCs. In situ labeling and visualization of migrating NPCs were analyzed...... by a longitudinal MRI study and validated with histology. Here, we visualized endogenous NPC migration in the mouse brain by in vivo MRI and demonstrated accumulation of MPIO-labeled NPCs in the OB over time with ex vivo MRI. Furthermore, we investigated the influence of in situ injection of MPIOs on adult...

  2. Lycium barbarum polysaccharides promotes in vivo proliferation of adult rat retinal progenitor cells

    Directory of Open Access Journals (Sweden)

    Hua Wang

    2015-01-01

    Full Text Available Lycium barbarum is a widely used Chinese herbal medicine prescription for protection of optic nerve. However, it remains unclear regarding the effects of Lycium barbarum polysaccharides, the main component of Lycium barbarum, on in vivo proliferation of adult ciliary body cells. In this study, adult rats were intragastrically administered low- and high-dose Lycium barbarum polysaccharides (1 and 10 mg/kg for 35 days and those intragastrically administered phosphate buffered saline served as controls. The number of Ki-67-positive cells in rat ciliary body in the Lycium barbarum polysaccharides groups, in particular low-dose Lycium barbarum polysaccharides group, was significantly greater than that in the phosphate buffered saline group. Ki-67-positive rat ciliary body cells expressed nestin but they did not express glial fibrillary acidic protein. These findings suggest that Lycium barbarum polysaccharides can promote the proliferation of adult rat retinal progenitor cells and the proliferated cells present with neuronal phenotype.

  3. Isolation and characterization of progenitor cells in uninjured, adult rat lacrimal gland

    DEFF Research Database (Denmark)

    Shatos, Marie A; Haugaard-Kedstrom, Linda; Hodges, Robin R

    2012-01-01

    (SMA), which marks myoepithelial cells (MECs), by immunofluorescence microscopy (IF). Small, immature cells were isolated after digestion of LG with collagenase and culture in RPMI 1640 for 2 weeks. Immature cells were examined for expression of stem cell markers by IF. Immature cell were grown...... in neuronal, epithelial, and myoepithelial cell media, and examined by light morphology and IF using antibodies to markers of different cell lineages. RESULTS: In the intact LGs, MECs expressed the stem cell markers nestin, Musashi 1, ABCG2, Pax6, Chx 10, ΔN p63, and Sox 2. All markers colocalized with SMA......, and labeled with the epithelial marker AE1/AE3. In RPMI media immature cells differentiated into cells with MEC-like morphology, and expressed the MEC markers SMA, α-actinin, adenylate cyclase II, and vimentin. CONCLUSIONS: We conclude that uninjured, adult LG contains progenitor cells that may be MECs, which...

  4. Vascular smooth muscle progenitor cells: building and repairing blood vessels.

    Science.gov (United States)

    Majesky, Mark W; Dong, Xiu Rong; Regan, Jenna N; Hoglund, Virginia J

    2011-02-04

    Molecular pathways that control the specification, migration, and number of available smooth muscle progenitor cells play key roles in determining blood vessel size and structure, capacity for tissue repair, and progression of age-related disorders. Defects in these pathways produce malformations of developing blood vessels, depletion of smooth muscle progenitor cell pools for vessel wall maintenance and repair, and aberrant activation of alternative differentiation pathways in vascular disease. A better understanding of the molecular mechanisms that uniquely specify and maintain vascular smooth muscle cell precursors is essential if we are to use advances in stem and progenitor cell biology and somatic cell reprogramming for applications directed to the vessel wall.

  5. Transplantation of enteric neural stem/progenitor cells into the irradiated young mouse hippocampus.

    Science.gov (United States)

    Osman, Ahmed M; Zhou, Kai; Zhu, Changlian; Blomgren, Klas

    2014-01-01

    Radiotherapy is an effective treatment for brain tumors but often results in cognitive deficits in survivors. Transplantation of embryonic or brain-derived neural stem/progenitor cells (BNSPCs) ameliorated cognitive impairment after irradiation (IR) in animal models. However, such an approach in patients requires a clinically relevant source of cells. We show for the first time the utilization of enteric neural stem/progenitor cells (ENSPCs) from the postnatal intestinal wall as a source of autologous cells for brain repair after injury caused by IR. Cells were isolated from the intestinal wall and propagated in vitro for 1 week. Differentiation assays showed that ENSPCs are multipotent and generated neurons, astrocytes, and myofibroblasts. To investigate whether ENSPCs can be used in vivo, postnatal day 9 mice were subjected to a single moderate irradiation dose (6 or 8 Gy). Twelve days later, mice received an intrahippocampal injection of syngeneic ENSPCs. Four weeks after transplantation, 0.5% and 1% of grafted ENSPCs were detected in the dentate gyrus of sham and irradiated animals, respectively, and only 0.1% was detected after 16 weeks. Grafted ENSPCs remained undifferentiated but failed to restore IR-induced loss of BNSPCs and the subsequent impaired growth of the dentate gyrus. We observed microglia activation, astrogliosis, and loss of granule neurons associated with grafted ENSPC clusters. Transplantation of ENSPCs did not ameliorate IR-induced impaired learning and memory. In summary, while autologous ENSPC grafting to the brain worked technically, even in the absence of immunosuppression, the protocols need to be modified to improve survival and integration.

  6. Intestinal epithelial stem/progenitor cells are controlled by mucosal afferent nerves.

    Directory of Open Access Journals (Sweden)

    Ove Lundgren

    Full Text Available BACKGROUND: The maintenance of the intestinal epithelium is of great importance for the survival of the organism. A possible nervous control of epithelial cell renewal was studied in rats and mice. METHODS: Mucosal afferent nerves were stimulated by exposing the intestinal mucosa to capsaicin (1.6 mM, which stimulates intestinal external axons. Epithelial cell renewal was investigated in the jejunum by measuring intestinal thymidine kinase (TK activity, intestinal (3H-thymidine incorporation into DNA, and the number of crypt cells labeled with BrdU. The influence of the external gut innervation was minimized by severing the periarterial nerves. PRINCIPAL FINDINGS: Luminal capsaicin increased all the studied variables, an effect nervously mediated to judge from inhibitory effects on TK activity or (3H-thymidine incorporation into DNA by exposing the mucosa to lidocaine (a local anesthetic or by giving four different neurotransmitter receptor antagonists i.v. (muscarinic, nicotinic, neurokinin1 (NK1 or calcitonin gene related peptide (CGRP receptors. After degeneration of the intestinal external nerves capsaicin did not increase TK activity, suggesting the involvement of an axon reflex. Intra-arterial infusion of Substance P (SP or CGRP increased intestinal TK activity, a response abolished by muscarinic receptor blockade. Immunohistochemistry suggested presence of M3 and M5 muscarinic receptors on the intestinal stem/progenitor cells. We propose that the stem/progenitor cells are controlled by cholinergic nerves, which, in turn, are influenced by mucosal afferent neuron(s releasing acetylcholine and/or SP and/or CGRP. In mice lacking the capsaicin receptor, thymidine incorporation into DNA and number of crypt cells labeled with BrdU was lower than in wild type animals suggesting that nerves are important also in the absence of luminal capsaicin, a conclusion also supported by the observation that atropine lowered thymidine incorporation into DNA

  7. Nestin is essential for zebrafish brain and eye development through control of progenitor cell apoptosis.

    Directory of Open Access Journals (Sweden)

    Hua-Ling Chen

    Full Text Available BACKGROUND: Nestin is expressed in neural progenitor cells (NPC of developing brain. Despite its wide use as an NPC marker, the function of nestin in embryo development is unclear. METHODOLOGY/PRINCIPAL FINDINGS: As nestin is conserved in zebrafish and its predicted sequence is clustered with the mammalian nestin orthologue, we used zebrafish as a model to investigate its role in embryogenesis. Injection of nestin morpholino (MO into fertilized eggs induced time- and dose-dependent brain and eye developmental defects. Nestin morphants exhibited characteristic morphological changes including small head, small eyes and hydrocephalus. Histological examinations show reduced hind- and mid-brain size, dilated ventricle, poorly organized retina and underdeveloped lens. Injection of control nestin MO did not induce brain or eye changes. Nestin MO injection reduced expression of ascl1b (achaete-scute complex-like 1b, a marker of NPCs, without affecting its distribution. Nestin MO did not influence Elavl3/4 (Embryonic lethal, abnormal vision, Drosophila-like 3/4 (a neuronal marker, or otx2 (a midbrain neuronal marker, but severely perturbed cranial motor nerve development and axon distribution. To determine whether the developmental defects are due to excessive NPC apoptosis and/or reduced NPC proliferation, we analyzed apoptosis by TUNEL assay and acridine orange staining and proliferation by BrdU incorporation, pcna and mcm5 expressions. Excessive apoptosis was noted in hindbrain and midbrain cells. Apoptotic signals were colocalized with ascl1b. Proliferation markers were not significantly altered by nestin MO. CONCLUSION/SIGNIFICANCE: These results suggest that nestin is essential for zebrafish brain and eye development probably through control of progenitor cell apoptosis.

  8. Hippocampal Adult Neurogenesis Is Maintained by Neil3-Dependent Repair of Oxidative DNA Lesions in Neural Progenitor Cells

    Directory of Open Access Journals (Sweden)

    Christine Elisabeth Regnell

    2012-09-01

    Full Text Available Accumulation of oxidative DNA damage has been proposed as a potential cause of age-related cognitive decline. The major pathway for removal of oxidative DNA base lesions is base excision repair, which is initiated by DNA glycosylases. In mice, Neil3 is the main DNA glycosylase for repair of hydantoin lesions in single-stranded DNA of neural stem/progenitor cells, promoting neurogenesis. Adult neurogenesis is crucial for maintenance of hippocampus-dependent functions involved in behavior. Herein, behavioral studies reveal learning and memory deficits and reduced anxiety-like behavior in Neil3−/− mice. Neural stem/progenitor cells from aged Neil3−/− mice show impaired proliferative capacity and reduced DNA repair activity. Furthermore, hippocampal neurons in Neil3−/− mice display synaptic irregularities. It appears that Neil3-dependent repair of oxidative DNA damage in neural stem/progenitor cells is required for maintenance of adult neurogenesis to counteract the age-associated deterioration of cognitive performance.

  9. Lineage tracing of neuromesodermal progenitors reveals novel Wnt-dependent roles in trunk progenitor cell maintenance and differentiation.

    Science.gov (United States)

    Garriock, Robert J; Chalamalasetty, Ravindra B; Kennedy, Mark W; Canizales, Lauren C; Lewandoski, Mark; Yamaguchi, Terry P

    2015-05-01

    In the development of the vertebrate body plan, Wnt3a is thought to promote the formation of paraxial mesodermal progenitors (PMPs) of the trunk region while suppressing neural specification. Recent lineage-tracing experiments have demonstrated that these trunk neural progenitors and PMPs derive from a common multipotent progenitor called the neuromesodermal progenitor (NMP). NMPs are known to reside in the anterior primitive streak (PS) region; however, the extent to which NMPs populate the PS and contribute to the vertebrate body plan, and the precise role that Wnt3a plays in regulating NMP self-renewal and differentiation are unclear. To address this, we used cell-specific markers (Sox2 and T) and tamoxifen-induced Cre recombinase-based lineage tracing to locate putative NMPs in vivo. We provide functional evidence for NMP location primarily in the epithelial PS, and to a lesser degree in the ingressed PS. Lineage-tracing studies in Wnt3a/β-catenin signaling pathway mutants provide genetic evidence that trunk progenitors normally fated to enter the mesodermal germ layer can be redirected towards the neural lineage. These data, combined with previous PS lineage-tracing studies, support a model that epithelial anterior PS cells are Sox2(+)T(+) multipotent NMPs and form the bulk of neural progenitors and PMPs of the posterior trunk region. Finally, we find that Wnt3a/β-catenin signaling directs trunk progenitors towards PMP fates; however, our data also suggest that Wnt3a positively supports a progenitor state for both mesodermal and neural progenitors. © 2015. Published by The Company of Biologists Ltd.

  10. Potential for cell therapy in Parkinson's disease using genetically programmed human embryonic stem cell-derived neural progenitor cells.

    Science.gov (United States)

    Ambasudhan, Rajesh; Dolatabadi, Nima; Nutter, Anthony; Masliah, Eliezer; Mckercher, Scott R; Lipton, Stuart A

    2014-08-15

    Neural transplantation is a promising strategy for restoring dopaminergic dysfunction and modifying disease progression in Parkinson's disease (PD). Human embryonic stem cells (hESCs) are a potential resource in this regard because of their ability to provide a virtually limitless supply of homogenous dopaminergic progenitors and neurons of appropriate lineage. The recent advances in developing robust cell culture protocols for directed differentiation of hESCs to near pure populations of ventral mesencephalic (A9-type) dopaminergic neurons has heightened the prospects for PD cell therapy. Here, we focus our review on current state-of-the-art techniques for harnessing hESC-based strategies toward development of a stem cell therapeutic for PD. Importantly, we also briefly describe a novel genetic-programming approach that may address many of the key challenges that remain in the field and that may hasten clinical translation. © 2014 Wiley Periodicals, Inc.

  11. Sequential generation of olfactory bulb glutamatergic neurons by Neurog2-expressing precursor cells

    Directory of Open Access Journals (Sweden)

    Brill Monika S

    2011-04-01

    Full Text Available Abstract Background While the diversity and spatio-temporal origin of olfactory bulb (OB GABAergic interneurons has been studied in detail, much less is known about the subtypes of glutamatergic OB interneurons. Results We studied the temporal generation and diversity of Neurog2-positive precursor progeny using an inducible genetic fate mapping approach. We show that all subtypes of glutamatergic neurons derive from Neurog2 positive progenitors during development of the OB. Projection neurons, that is, mitral and tufted cells, are produced at early embryonic stages, while a heterogeneous population of glutamatergic juxtaglomerular neurons are generated at later embryonic as well as at perinatal stages. While most juxtaglomerular neurons express the T-Box protein Tbr2, those generated later also express Tbr1. Based on morphological features, these juxtaglomerular cells can be identified as tufted interneurons and short axon cells, respectively. Finally, targeted electroporation experiments provide evidence that while the majority of OB glutamatergic neurons are generated from intrabulbar progenitors, a small portion of them originate from extrabulbar regions at perinatal ages. Conclusions We provide the first comprehensive analysis of the temporal and spatial generation of OB glutamatergic neurons and identify distinct populations of juxtaglomerular interneurons that differ in their antigenic properties and time of origin.

  12. Isolation of locally derived stem/progenitor cells from the peri-infarct area that do not migrate from the lateral ventricle after cortical stroke.

    Science.gov (United States)

    Shimada, Issei S; Peterson, Brittni M; Spees, Jeffrey L

    2010-09-01

    Neurogenesis can arise from neural stem/progenitor cells of the subventricular zone after strokes involving both the cortex and striatum. However, it is controversial whether all types of stroke and strokes of different sizes activate neurogenesis from the subventricular zone niche. In contrast with cortical/striatal strokes, repair and remodeling after mild cortical strokes may involve to a greater extent local cortical stem/progenitor cells and cells from nonneurogenic niches. We compared stem/progenitor cell responses after focal cortical strokes produced by distal middle cerebral artery occlusion and cortical/striatal strokes produced by the intraluminal suture model. To label migrating neuroblasts from the subventricular zone, we injected DiI to the lateral ventricle after distal middle cerebral artery occlusion. By immunohistochemistry, we characterized cells expressing stem/progenitor cell markers in the peri-infarct area. We isolated cortical stem/progenitor cells from the peri-infarct area after distal middle cerebral artery occlusion and assayed their self-renewal and differentiation capacity. In contrast with cortical/striatal strokes, focal cortical strokes did not induce neuroblast migration from the subventricular zone to the infarct zone after distal middle cerebral artery occlusion. By immunohistochemistry, we observed subpopulations of reactive astrocytes in the peri-infarct area that coexpressed radial glial cell markers such as Sox2, Nestin, and RC2. Clonal neural spheres isolated from the peri-infarct area after distal middle cerebral artery occlusion differentiated into neurons, astrocytes, oligodendrocytes, and smooth muscle cells. Notably, neural spheres isolated from the peri-infarct area also expressed RC2 before differentiation. Mild cortical strokes that do not penetrate the striatum activate local cortical stem/progenitor cells but do not induce neuroblast migration from the subventricular zone niche.

  13. Delayed rectifier and A-type potassium channels associated with Kv 2.1 and Kv 4.3 expression in embryonic rat neural progenitor cells.

    Directory of Open Access Journals (Sweden)

    Dean O Smith

    Full Text Available BACKGROUND: Because of the importance of voltage-activated K(+ channels during embryonic development and in cell proliferation, we present here the first description of these channels in E15 rat embryonic neural progenitor cells derived from the subventricular zone (SVZ. Activation, inactivation, and single-channel conductance properties of recorded progenitor cells were compared with those obtained by others when these Kv gene products were expressed in oocytes. METHODOLOGY/PRINCIPAL FINDINGS: Neural progenitor cells derived from the subventricular zone of E15 embryonic rats were cultured under conditions that did not promote differentiation. Immunocytochemical and Western blot assays for nestin expression indicated that almost all of the cells available for recording expressed this intermediate filament protein, which is generally accepted as a marker for uncommitted embryonic neural progenitor cells. However, a very small numbers of the cells expressed GFAP, a marker for astrocytes, O4, a marker for immature oligodendrocytes, and betaIII-tubulin, a marker for neurons. Using immunocytochemistry and Western blots, we detected consistently the expression of Kv2.1, and 4.3. In whole-cell mode, we recorded two outward currents, a delayed rectifier and an A-type current. CONCLUSIONS/SIGNIFICANCE: We conclude that Kv2.1, and 4.3 are expressed in E15 SVZ neural progenitor cells, and we propose that they may be associated with the delayed-rectifier and the A-type currents, respectively, that we recorded. These results demonstrate the early expression of delayed rectifier and A-type K(+ currents and channels in embryonic neural progenitor cells prior to the differentiation of these cells.

  14. Golli Myelin Basic Proteins Modulate Voltage-Operated Ca(++) Influx and Development in Cortical and Hippocampal Neurons.

    Science.gov (United States)

    Vt, Cheli; DA, Santiago González; V, Spreuer; V, Handley; At, Campagnoni; Pm, Paez

    2016-10-01

    The golli proteins, products of the myelin basic protein gene, are widely expressed in oligodendrocyte progenitor cells and neurons during the postnatal development of the brain. While golli appears to be important for oligodendrocyte migration and differentiation, its function in neuronal development is completely unknown. We have found that golli proteins function as new and novel modulators of voltage-operated Ca(++) channels (VOCCs) in neurons. In vitro, golli knock-out (KO) neurons exhibit decreased Ca(++) influx after plasma membrane depolarization and a substantial maturational delay. Increased expression of golli proteins enhances L-type Ca(++) entry and processes outgrowth in cortical neurons, and pharmacological activation of L-type Ca(++) channels stimulates maturation and prevents cell death in golli-KO neurons. In situ, Ca(++) influx mediated by L-type VOCCs was significantly decreased in cortical and hippocampal neurons of the golli-KO brain. These Ca(++) alterations affect cortical and hippocampal development and the proliferation and survival of neural progenitor cells during the postnatal development of the golli-KO brain. The CA1/3 sections and the dentate gyrus of the hippocampus were reduced in the golli-KO mice as well as the density of dendrites in the somatosensory cortex. Furthermore, the golli-KO mice display abnormal behavior including deficits in episodic memory and reduced anxiety. Because of the expression of the golli proteins within neurons in learning and memory centers of the brain, this work has profound implication in neurodegenerative diseases and neurological disorders.

  15. Observational clues to the progenitors of Type-Ia supernovae

    CERN Document Server

    Maoz, Dan; Nelemans, Gijs

    2013-01-01

    Type-Ia supernovae (SNe Ia) are important distance indicators, element factories, cosmic-ray accelerators, kinetic-energy sources in galaxy evolution, and endpoints of stellar binary evolution. It has long been clear that a SN Ia must be the runaway thermonuclear explosion of a degenerate carbon-oxygen stellar core, most likely a white dwarf (WD). However, the specific progenitor systems of SNe Ia, and the processes that lead to their ignition, have not been identified. Two broad classes of progenitor binary systems have long been considered: single-degenerate (SD), in which a WD gains mass from a non-degenerate star; and double-degenerate (DD), involving the merger of two WDs. New theoretical work has enriched these possibilities with some interesting updates and variants. We review the significant recent observational progress in addressing the progenitor problem. We consider clues that have emerged from the observed properties of the various proposed progenitor populations, from studies of their sites, pre...

  16. Luminal progenitors restrict their lineage potential during mammary gland development.

    Science.gov (United States)

    Rodilla, Veronica; Dasti, Alessandro; Huyghe, Mathilde; Lafkas, Daniel; Laurent, Cécile; Reyal, Fabien; Fre, Silvia

    2015-02-01

    The hierarchical relationships between stem cells and progenitors that guide mammary gland morphogenesis are still poorly defined. While multipotent basal stem cells have been found within the myoepithelial compartment, the in vivo lineage potential of luminal progenitors is unclear. Here we used the expression of the Notch1 receptor, previously implicated in mammary gland development and tumorigenesis, to elucidate the hierarchical organization of mammary stem/progenitor cells by lineage tracing. We found that Notch1 expression identifies multipotent stem cells in the embryonic mammary bud, which progressively restrict their lineage potential during mammary ductal morphogenesis to exclusively generate an ERαneg luminal lineage postnatally. Importantly, our results show that Notch1-labelled cells represent the alveolar progenitors that expand during pregnancy and survive multiple successive involutions. This study reveals that postnatal luminal epithelial cells derive from distinct self-sustained lineages that may represent the cells of origin of different breast cancer subtypes.

  17. Trichothecene toxicity on human megakaryocyte progenitors (CFU-MK).

    Science.gov (United States)

    Froquet, R; Sibiril, Y; Parent-Massin, D

    2001-02-01

    Trichothecenes are mycotoxins produced by various species of fungi, which can occur on various agricultural products. Among these compounds, T-2 toxin, HT-2 toxin, diacetoxyscirpenol (DAS) and deoxynivalenol (DON) are the most naturally encountered and the most potent trichothecenes. Consumption of trichothecene contaminated foods by farm animals and humans leads to mycotoxicosis. Trichothecenes are known to induce haematological disorders such as neutropenia, aplastic anemia and thrombocytopenia in humans and animals. Four trichothecenes, T-2 toxin, HT-2 toxin, DAS and DON have been tested on human platelet progenitors (CFU-MK) using a culture model of CFU-MK optimized for toxicological studies. Trichothecenes cause, at low concentrations, cytotoxic effects in megakaryocyte progenitors, which could induce thrombocytopenia. Sensitivity of human CFU-MK is compared to respective sensitivities of human red blood cell progenitors (BFU-E) and white blood cell progenitors (CF-U-GM) that were described in previous works.

  18. On Measuring the Metallicity of Supernovae Type Ia Progenitors

    CERN Document Server

    Miles, Broxton J; Townsley, Dean M; Timmes, F X; Jackson, Aaron P; Calder, Alan C; Brown, Edward F

    2015-01-01

    In Type Ia Supernovae (\\sneia), the relative abundances of chemical elements are affected by the neutron excess in the composition of the progenitor white dwarf. Since these products leave signatures in the spectra near maximum light, spectral features may be used to constrain the composition of the progenitor. We calculate the nucleosynthetic yields for three \\snia simulations for a wide range of progenitor metallicities, and calculate synthetic light curves and spectra to explore correlations between progenitor metallicity and the strength of spectral features. We use two 2D simulations of the deflagration-detonation-transition scenario with different $^{56}$Ni yields and the W7 simulation to control for differences between explosion models and total yields. While the overall yields of intermediate mass elements (16 $<$ A $\\leq$ 40) differ between the three cases, trends in the yields are similar. With increasing metallicity, $^{28}$Si yields remain nearly constant, $^{40}$Ca yields decline, and Ti and $...

  19. Senegenin promotes in vitro proliferation of human neural progenitor cells

    Institute of Scientific and Technical Information of China (English)

    Fang Shi; Zhigang Liang; Zixuan Guo; Ran Li; Fen Yu; Zhanjun Zhang; Xuan Wang; Xiaomin Wang

    2011-01-01

    Senegenin, an effective component of Polygala tenuifolia root extract, promotes proliferation and differentiation of neural progenitor cells in the hippocampus.However, the effects of senegenin on mesencephalon-derived neural progenitor cells remain poorly understood.Cells from a ventral mesencephalon neural progenitor cell line (ReNcell VM) were utilized as models for pharmaceutical screening.The effects of various senegenin concentrations on cell proliferation were analyzed,demonstrating that high senegenin concentrations (5, 10, 50, and 100 pmo/L), particularly 50 pmol/L, significantly promoted proliferation of ReNcell VM cells.In the mitogen-activated protein kinase signal transduction pathway, senegenin significantly increased phosphorylation levels of extracellular signal-regulated kinases.Moreover, cell proliferation was suppressed by extracellular signal-regulated kinase inhibitors.Results suggested that senegenin contributed to in vitro proliferation of human neural progenitor cells by upregulating phosphorylation of extracellular signal-regulated kinase.

  20. Luminal progenitors restrict their lineage potential during mammary gland development.

    Directory of Open Access Journals (Sweden)

    Veronica Rodilla

    2015-02-01

    Full Text Available The hierarchical relationships between stem cells and progenitors that guide mammary gland morphogenesis are still poorly defined. While multipotent basal stem cells have been found within the myoepithelial compartment, the in vivo lineage potential of luminal progenitors is unclear. Here we used the expression of the Notch1 receptor, previously implicated in mammary gland development and tumorigenesis, to elucidate the hierarchical organization of mammary stem/progenitor cells by lineage tracing. We found that Notch1 expression identifies multipotent stem cells in the embryonic mammary bud, which progressively restrict their lineage potential during mammary ductal morphogenesis to exclusively generate an ERαneg luminal lineage postnatally. Importantly, our results show that Notch1-labelled cells represent the alveolar progenitors that expand during pregnancy and survive multiple successive involutions. This study reveals that postnatal luminal epithelial cells derive from distinct self-sustained lineages that may represent the cells of origin of different breast cancer subtypes.

  1. Characterizing PCDH19 in human induced pluripotent stem cells (iPSCs) and iPSC-derived developing neurons: emerging role of a protein involved in controlling polarity during neurogenesis.

    Science.gov (United States)

    Compagnucci, Claudia; Petrini, Stefania; Higuraschi, Norimichi; Trivisano, Marina; Specchio, Nicola; Hirose, Shinichi; Bertini, Enrico; Terracciano, Alessandra

    2015-09-29

    PCDH19 (Protocadherin 19), a member of the cadherin superfamily, is involved in the pathogenic mechanism of an X-linked model of neurological disease. The biological function of PCHD19 in human neurons and during neurogenesis is currently unknown. Therefore, we decided to use the model of the induced pluripotent stem cells (iPSCs) to characterize the location and timing of expression of PCDH19 during cortical neuronal differentiation. Our data show that PCDH19 is expressed in pluripotent cells before differentiation in a homogeneous pattern, despite its localization is often limited to one pole of the cell. During neuronal differentiation, positional information on the progenitor cells assumes an important role in acquiring polarization. The proper control of the cell orientation ensures a fine balancing between symmetric (giving rise to two progenitor sister cells) versus asymmetric (giving rise to one progenitor cell and one newborn neuron) division. This process results in the polar organization of the neural tube with a lumen indicating the basal part of the polarized neuronal progenitor cell; in the iPSC model the cells are organized in the 'neural rosette' and interestingly, PCDH19 is located at the center of the rosette, with other well-known markers of the lumen (N-cadherin and ZO-1). These data suggest that PCDH19 has a role in instructing the apico-basal polarity of the progenitor cells, thus regulating the development of a properly organized human brain.

  2. Endothelial progenitor cells with Alzheimer's disease

    Institute of Scientific and Technical Information of China (English)

    KONG Xiao-dong; ZHANG Yun; LIU Li; SUN Ning; ZHANG Ming-yi; ZHANG Jian-ning

    2011-01-01

    Background Endothelial dysfunction is thought to be critical events in the pathogenesis of Alzheimer's disease (AD).Endothelial progenitor cells (EPCs) have provided insight into maintaining and repairing endothelial function. To study the relation between EPCs and AD, we explored the number of circulating EPCs in patients with AD.Methods A total of 104 patients were recruited from both the outpatients and inpatients of the geriatric neurology department at General Hospital, rianjin Medical University. Consecutive patients with newly diagnosed AD (n=30),patients with vascular dementia (VaD, n=34), and healthy elderly control subjects with normal cognition (n=40) were enrolled after matching for age, gender, body mass index, medical history, current medication and Mini Mental State Examination. Middle cerebral artery flow velocity was examined with transcranial Doppler. Endothelial function was evaluated according to the level of EPCs, and peripheral blood EPCs was counted by flow cytometry.Results There were no significant statistical differences of clinical data in AD, VaD and control groups (P >0.05). The patients with AD showed decreased CD34-positive (CD34+) or CD133-positive (CD133+) levels compared to the control subjects, but there were no significant statistical differences in patients with AD. The patients with AD had significantly lower CD34+CD133+ EPCs(CD34 and CD133 double positive endothelial progenitor cells) than the control subjects (P <0.05). In the patients with AD, a lower CD34+CD133+ EPCs count was independently associated with a lower Mini-Mental State Examination score (r=0.514, P=0.004). Patients with VaD also showed a significant decrease in CD34+CD133+ EPCs levels, but this was not evidently associated with the Mini-Mental State Examination score. The changes of middle cerebral artery flow velocity were similar between AD and VaD. Middle cerebral artery flow velocity was decreased in the AD and VaD groups and significantly lower than

  3. Endothelial Progenitor Cells for Diagnosis and Prognosis in Cardiovascular Disease

    OpenAIRE

    2015-01-01

    Objective. To identify, evaluate, and synthesize evidence on the predictive power of circulating endothelial progenitor cells (EPCs) in cardiovascular disease, through a systematic review of quantitative studies. Data Sources. MEDLINE was searched using keywords related to “endothelial progenitor cells” and “endothelium” and, for the different categories, respectively, “smoking”; “blood pressure”; “diabetes mellitus” or “insulin resistance”; “dyslipidemia”; “aging” or “elderly”; “angina p...

  4. Human pancreatic islet progenitor cells demonstrate phenotypic plasticity in vitro

    Indian Academy of Sciences (India)

    Maithili P Dalvi; Malati R Umrani; Mugdha V Joglekar; Anandwardhan A Hardikar

    2009-10-01

    Phenotypic plasticity is a phenomenon that describes the occurrence of 2 or more distinct phenotypes under diverse conditions. This article discusses the work carried out over the past few years in understanding the potential of human pancreatic islet-derived progenitors for cell replacement therapy in diabetes. The phenotypic plasticity exhibited by pancreatic progenitors during reversible epithelial-to-mesenchymal transition (EMT) and possible role of microRNAs in regulation of this process is also presented herein.

  5. NDUFV2 regulates neuronal migration in the developing cerebral cortex through modulation of the multipolar-bipolar transition.

    Science.gov (United States)

    Chen, Tianda; Wu, Qinwei; Zhang, Yang; Zhang, Dai

    2015-11-02

    Abnormalities during brain development are tightly linked several psychiatric disorders. Mutations in NADH dehydrogenase ubiquinone flavoprotein 2 (NDUFV2) are responsible for schizophrenia, bipolar disorder and Parkinson׳s disease. However, the function of NDUFV2 during brain development remains unclear. Here we reported that ndufv2 is expressed in the developing cerebral cortex. In utero suppression of ndufv2 arrested neuronal migration, leading to accumulation of ectopic neurons in the intermediate zone. ndufv2 inhibition did not affect radial glia scaffold, progenitor cells or neurons survival. However, the loss of ndufv2 impairs neuronal multipolar-bipolar transition in vivo and polarization in vitro. Moreover, ndufv2 affected actin cytoskeleton and tubulin stabilization in cortical neurons. Overall, our findings establish a new NDUFV2 dependent mechanism underlying neuronal migration and psychiatric disorders.

  6. Trasplante de progenitores hemopoyéticos Transplant of hemopoietic progenitors

    Directory of Open Access Journals (Sweden)

    J. J. Rifón

    2006-08-01

    Full Text Available En la segunda mitad del siglo XX el trasplante de progenitores hemopoyéticos ha pasado de ser un tratamiento desesperado con una alta incidencia de complicaciones que implicaba una elevada mortalidad, a ser un tratamiento curativo para miles de pacientes con neoplasias hematológicas y otras enfermedades. Desde entonces se han ampliado los conocimientos sobre las células madre hemopoyéticas, la sangre periférica ha sustituido a la médula ósea como fuente de progenitores, la sangre de cordón se ha establecido como fuente viable de progenitores, la realización de trasplantes no emparentados es una realidad para muchos pacientes. La mejora en los regímenes de acondicionamiento y la introducción de los regímenes no mieloablativos han disminuido las recaídas. Las nuevas técnicas diagnósticas y los nuevos tratamientos antimicrobianos han disminuido las complicaciones infecciosas y su mortalidad. Se han desarrollado los conocimientos en determinación de enfermedad mínima residual y el efecto antitumoral de los linfocitos del donante lo que ha permitido ampliar las indicaciones. Además, los nuevos conocimientos en la inmunobiología del trasplante han mejorado por un lado las opciones de controlar una de las principales complicaciones como es la enfermedad injerto contra huésped, y por otro un mejor aprovechamiento del efecto inmunoterápico del trasplante.In the second half of the XX century, the transplant of hemopoietic progenitors ceased to be a desperate treatment with a high incidence of complications implying a high mortality, and became a curative treatment for thousands of patients with hematological neoplasias and other diseases. Since then understanding of the hemopoietic stem cells has increased, peripheral blood has replaced bone marrow as a source of progenitors, cord blood has been established as a viable source of progenitors and the realisation of unrelated transplants is a reality for many patients. The improvement of

  7. Nkx2.2 and Nkx2.9 are the key regulators to determine cell fate of branchial and visceral motor neurons in caudal hindbrain.

    Science.gov (United States)

    Jarrar, Wassan; Dias, Jose M; Ericson, Johan; Arnold, Hans-Henning; Holz, Andreas

    2015-01-01

    Cranial motor nerves in vertebrates are comprised of the three principal subtypes of branchial, visceral, and somatic motor neurons, which develop in typical patterns along the anteroposterior and dorsoventral axes of hindbrain. Here we demonstrate that the formation of branchial and visceral motor neurons critically depends on the transcription factors Nkx2.2 and Nkx2.9, which together determine the cell fate of neuronal progenitor cells. Disruption of both genes in mouse embryos results in complete loss of the vagal and spinal accessory motor nerves, and partial loss of the facial and glossopharyngeal motor nerves, while the purely somatic hypoglossal and abducens motor nerves are not diminished. Cell lineage analysis in a genetically marked mouse line reveals that alterations of cranial nerves in Nkx2.2; Nkx2.9 double-deficient mouse embryos result from changes of cell fate in neuronal progenitor cells. As a consequence progenitors of branchiovisceral motor neurons in the ventral p3 domain of hindbrain are transformed to somatic motor neurons, which use ventral exit points to send axon trajectories to their targets. Cell fate transformation is limited to the caudal hindbrain, as the trigeminal nerve is not affected in double-mutant embryos suggesting that Nkx2.2 and Nkx2.9 proteins play no role in the development of branchiovisceral motor neurons in hindbrain rostral to rhombomere 4.

  8. Prospective separation and transcriptome analyses of cortical projection neurons and interneurons based on lineage tracing by Tbr2 (Eomes)-GFP/Dcx-mRFP reporters.

    Science.gov (United States)

    Liu, Jiancheng; Wu, Xiwei; Zhang, Heying; Qiu, Runxiang; Yoshikawa, Kazuaki; Lu, Qiang

    2016-06-01

    In the cerebral cortex, projection neurons and interneurons work coordinately to establish neural networks for normal cortical functions. While the specific mechanisms that control productions of projection neurons and interneurons are beginning to be revealed, a global characterization of the molecular differences between these two neuron types is crucial for a more comprehensive understanding of their developmental specifications and functions. In this study, using lineage tracing power of combining Tbr2(Eomes)-GFP and Dcx-mRFP reporter mice, we prospectively separated intermediate progenitor cell (IPC)-derived neurons (IPNs) from non-IPC-derived neurons (non-IPNs) of the embryonic cerebral cortex. Molecular characterizations revealed that IPNs and non-IPNs were enriched with projection neurons and interneurons, respectively. Expression profiling documented cell-specific genes including differentially expressed transcriptional regulators that might be involved in cellular specifications, for instance, our data found that SOX1 and SOX2, which were known for important functions in neural stem/progenitor cells, continued to be expressed by interneurons but not by projection neurons. Transcriptome analyses of cortical neurons isolated at different stages of neurogenesis revealed distinct temporal patterns of expression of genes involved in early-born or late-born neuron specification. These data present a resource useful for further investigation of the molecular regulations and functions of projection neurons and interneurons.

  9. Invited review: mesenchymal progenitor cells in intramuscular connective tissue development.

    Science.gov (United States)

    Miao, Z G; Zhang, L P; Fu, X; Yang, Q Y; Zhu, M J; Dodson, M V; Du, M

    2016-01-01

    The abundance and cross-linking of intramuscular connective tissue contributes to the background toughness of meat, and is thus undesirable. Connective tissue is mainly synthesized by intramuscular fibroblasts. Myocytes, adipocytes and fibroblasts are derived from a common pool of progenitor cells during the early embryonic development. It appears that multipotent mesenchymal stem cells first diverge into either myogenic or non-myogenic lineages; non-myogenic mesenchymal progenitors then develop into the stromal-vascular fraction of skeletal muscle wherein adipocytes, fibroblasts and derived mesenchymal progenitors reside. Because non-myogenic mesenchymal progenitors mainly undergo adipogenic or fibrogenic differentiation during muscle development, strengthening progenitor proliferation enhances the potential for both intramuscular adipogenesis and fibrogenesis, leading to the elevation of both marbling and connective tissue content in the resulting meat product. Furthermore, given the bipotent developmental potential of progenitor cells, enhancing their conversion to adipogenesis reduces fibrogenesis, which likely results in the overall improvement of marbling (more intramuscular adipocytes) and tenderness (less connective tissue) of meat. Fibrogenesis is mainly regulated by the transforming growth factor (TGF) β signaling pathway and its regulatory cascade. In addition, extracellular matrix, a part of the intramuscular connective tissue, provides a niche environment for regulating myogenic differentiation of satellite cells and muscle growth. Despite rapid progress, many questions remain in the role of extracellular matrix on muscle development, and factors determining the early differentiation of myogenic, adipogenic and fibrogenic cells, which warrant further studies.

  10. Interstitial stromal progenitors during kidney development: here, there and everywhere.

    Science.gov (United States)

    Fanni, Daniela; Gerosa, Clara; Vinci, Laura; Ambu, Rossano; Dessì, Angelica; Eyken, Peter Van; Fanos, Vassilios; Faa, Gavino

    2016-12-01

    In recent years, the renal interstitium has been identified as the site of multiple cell types, giving rise to multiple contiguous cellular networks with multiple fundamental structural and functional roles. Few studies have been carried out on the morphological and functional properties of the stromal/interstitial renal cells during the intrauterine life. This work was aimed at reviewing the peculiar features of renal interstitial stem/progenitor cells involved in kidney development. The origin of the renal interstitial progenitor cells remains unknown. During kidney development, besides the Six2 + cells of the cap mesenchyme, a self-renewing progenitor population, characterized by the expression of Foxd1, represents the first actor of the non-nephrogenic lineage. Foxd1 + interstitial progenitors originate the cortical and the renal medullary interstitial progenitors. Here, the most important stromal/interstitial compartments present in the developing human kidney will be analyzed: capsular stromal cells, cortical interstitial cells, medullary interstitial cells, the interstitium inside the renal stem cell niche, Hilar interstitial cells and Ureteric interstitial cells. Data reported here indicate that the different interstitial compartments of the developing kidney are formed by different cell types that characterize the different renal areas. Further studies are needed to better characterize the different pools of renal interstitial progenitors and their role in human nephrogenesis.

  11. On the progenitor of the Type IIb supernova 2016gkg

    Science.gov (United States)

    Kilpatrick, Charles D.; Foley, Ryan J.; Abramson, Louis E.; Pan, Yen-Chen; Lu, Cicero-Xinyu; Williams, Peter; Treu, Tommaso; Siebert, Matthew R.; Fassnacht, Christopher D.; Max, Claire E.

    2017-03-01

    We present a detection in pre-explosion Hubble Space Telescope (HST) imaging of a point source consistent with being the progenitor star of the Type IIb supernova (SN IIb) 2016gkg. Post-explosion imaging from the Keck adaptive optics system was used to perform relative astrometry between the Keck and HST imaging. We identify a single point source in the HST images coincident with the SN position to 0.89σ. The HST photometry is consistent with the progenitor star being an A0 Ia star with T = 9500 K and log (L/L⊙) = 5.15. We find that the SN 2016gkg progenitor star appears more consistent with binary than single-star evolutionary models. In addition, early-time light-curve data from SN 2016gkg revealed a rapid rise in luminosity within ∼0.4 d of non-detection limits, consistent with models of the cooling phase after shock break-out. We use these data to determine an explosion date of 2016 September 20.15 and progenitor-star radius of log (R/R⊙) = 2.41, which agrees with photometry from the progenitor star. Our findings are also consistent with detections of other SNe IIb progenitor stars, although more luminous and bluer than most other examples.

  12. Hematopoietic progenitor cell mobilization for autologous transplantation - a literature review

    Directory of Open Access Journals (Sweden)

    Marco Aurélio Salvino

    2016-02-01

    Full Text Available ABSTRACT The use of high-dose chemotherapy with autologous support of hematopoietic progenitor cells is an effective strategy to treat various hematologic neoplasms, such as non-Hodgkin lymphomas and multiple myeloma. Mobilized peripheral blood progenitor cells are the main source of support for autologous transplants, and collection of an adequate number of hematopoietic progenitor cells is a critical step in the autologous transplant procedure. Traditional strategies, based on the use of growth factors with or without chemotherapy, have limitations even when remobilizations are performed. Granulocyte colony-stimulating factor is the most widely used agent for progenitor cell mobilization. The association of plerixafor, a C-X-C Chemokine receptor type 4 (CXCR4 inhibitor, to granulocyte colony stimulating factor generates rapid mobilization of hematopoietic progenitor cells. A literature review was performed of randomized studies comparing different mobilization schemes in the treatment of multiple myeloma and lymphomas to analyze their limitations and effectiveness in hematopoietic progenitor cell mobilization for autologous transplant. This analysis showed that the addition of plerixafor to granulocyte colony stimulating factor is well tolerated and results in a greater proportion of patients with non-Hodgkin lymphomas or multiple myeloma reaching optimal CD34+ cell collections with a smaller number of apheresis compared the use of granulocyte colony stimulating factor alone.

  13. Study of a new neuron

    CERN Document Server

    Adler, Stephen Louis; Weckel, J D

    1994-01-01

    We study a modular neuron alternative to the McCulloch-Pitts neuron that arises naturally in analog devices in which the neuron inputs are represented as coherent oscillatory wave signals. Although the modular neuron can compute XOR at the one neuron level, it is still characterized by the same Vapnik-Chervonenkis dimension as the standard neuron. We give the formulas needed for constructing networks using the new neuron and training them using back-propagation. A numerical study of the modular neuron on two data sets is presented, which demonstrates that the new neuron performs at least as well as the standard neuron.

  14. Galectin-1 is expressed in early-type neural progenitor cells and down-regulates neurogenesis in the adult hippocampus

    Directory of Open Access Journals (Sweden)

    Imaizumi Yoichi

    2011-01-01

    Full Text Available Abstract Background In the adult mammalian brain, neural stem cells (NSCs proliferate in the dentate gyrus (DG of the hippocampus and generate new neurons throughout life. A multimodal protein, Galectin-1, is expressed in neural progenitor cells (NPCs and implicated in the proliferation of the NPCs in the DG. However, little is known about its detailed expression profile in the NPCs and functions in adult neurogenesis in the DG. Results Our immunohistochemical and morphological analysis showed that Galectin-1 was expressed in the type 1 and 2a cells, which are putative NSCs, in the subgranular zone (SGZ of the adult mouse DG. To study Galectin-1's function in adult hippocampal neurogenesis, we made galectin-1 knock-out mice on the C57BL6 background and characterized the effects on neurogenesis. In the SGZ of the galectin-1 knock-out mice, increased numbers of type 1 cells, DCX-positive immature progenitors, and NeuN-positive newborn neurons were observed. Using triple-labeling immunohistochemistry and morphological analyses, we found that the proliferation of the type-1 cells was increased in the SGZ of the galectin-1 knock-out mice, and we propose that this proliferation is the mechanism for the net increase in the adult neurogenesis in these knock-out mice DG. Conclusions Galectin-1 is expressed in the neural stem cells and down-regulates neurogenesis in the adult hippocampus.

  15. Cyclin D2 in the basal process of neural progenitors is linked to non-equivalent cell fates

    Science.gov (United States)

    Tsunekawa, Yuji; Britto, Joanne M; Takahashi, Masanori; Polleux, Franck; Tan, Seong-Seng; Osumi, Noriko

    2012-01-01

    Asymmetric cell division plays an indispensable role during corticogenesis for producing new neurons while maintaining a self-renewing pool of apical progenitors. The cellular and molecular determinants favouring asymmetric division are not completely understood. Here, we identify a novel mechanism for generating cellular asymmetry through the active transportation and local translation of Cyclin D2 mRNA in the basal process. This process is regulated by a unique cis-regulatory sequence found in the 3′ untranslated region (3′UTR) of the mRNA. Unequal inheritance of Cyclin D2 protein to the basally positioned daughter cell with the basal process confers renewal of the apical progenitor after asymmetric division. Conversely, depletion of Cyclin D2 in the apically positioned daughter cell results in terminal neuronal differentiation. We demonstrate that Cyclin D2 is also expressed in the developing human cortex within similar domains, thus indicating that its role as a fate determinant is ancient and conserved. PMID:22395070

  16. C-MYC transcriptionally amplifies SOX2 target genes to regulate self-renewal in multipotent otic progenitor cells.

    Science.gov (United States)

    Kwan, Kelvin Y; Shen, Jun; Corey, David P

    2015-01-13

    Sensorineural hearing loss is caused by the loss of sensory hair cells and neurons of the inner ear. Once lost, these cell types are not replaced. Two genes expressed in the developing inner ear are c-Myc and Sox2. We created immortalized multipotent otic progenitor (iMOP) cells, a fate-restricted cell type, by transient expression of C-MYC in SOX2-expressing otic progenitor cells. This activated the endogenous C-MYC and amplified existing SOX2-dependent transcripts to promote self-renewal. RNA-seq and ChIP-seq analyses revealed that C-MYC and SOX2 occupy over 85% of the same promoters. C-MYC and SOX2 target genes include cyclin-dependent kinases that regulate cell-cycle progression. iMOP cells continually divide but retain the ability to differentiate into functional hair cells and neurons. We propose that SOX2 and C-MYC regulate cell-cycle progression of these cells and that downregulation of C-MYC expression after growth factor withdrawal serves as a molecular switch for differentiation. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  17. Reciprocal actions of microRNA-9 and TLX in the proliferation and differentiation of retinal progenitor cells.

    Science.gov (United States)

    Hu, Yamin; Luo, Min; Ni, Ni; Den, Yuan; Xia, Jing; Chen, Junzhao; Ji, Jing; Zhou, Xiaojian; Fan, Xianqun; Gu, Ping

    2014-11-15

    Recent research has demonstrated critical roles of a number of microRNAs (miRNAs) in stem cell proliferation and differentiation. miRNA-9 (miR-9) is a brain-enriched miRNA. Whether miR-9 has a role in retinal progenitor cell (RPC) proliferation and differentiation remains unknown. In this study, we show that miR-9 plays an important role in RPC fate determination. The expression of miR-9 was inversely correlated with that of the nuclear receptor TLX, which is an essential regulator of neural stem cell self-renewal. Overexpression of miR-9 downregulated the TLX levels in RPCs, leading to reduced RPC proliferation and increased neuronal and glial differentiation, and the effect of miR-9 overexpression on RPC proliferation and differentiation was inhibited by the TLX overexpression; knockdown of miR-9 resulted in increased TLX expression as well as enhanced proliferation of RPCs. Furthermore, inhibition of endogenous TLX by small interfering RNA suppressed RPC proliferation and promoted RPCs to differentiate into retinal neuronal and glial cells. These results suggest that miR-9 and TLX form a feedback regulatory loop to coordinate the proliferation and differentiation of retinal progenitors.

  18. The Binary Progenitor of Tycho Brahe's Supernova

    Science.gov (United States)

    Ruiz-Lapuente, P.

    2006-08-01

    The brightness of type Ia supernovae, and their homogeneity as a class, makes them powerful tools in cosmology, yet little is known about the progenitor systems of these explosions. They are thought to arise when a white dwarf accretes matter from a companion star, is compressed and undergoes a thermonuclear explosion. Unless the companion star is another white dwarf (in which case it should be destroyed by the mass-transfer process itself), it should survive and show distinguishing properties. Tycho's supernova (SN 1572) provides an opportunity to address observationally the identification of the surviving companion. Here we report a survey of the central region of its remnant, around the position of the explosion, which excludes red giants as the mass donor of the exploding white dwarf. We found a type G0-G2 star, similar to our Sun in surface temperature and luminosity (but lower surface gravity), moving at more than three times the mean velocity of the stars at that distance, which appears to be the surviving companion of the supernova.

  19. Role of liver progenitors in liver regeneration.

    Science.gov (United States)

    Best, Jan; Manka, Paul; Syn, Wing-Kin; Dollé, Laurent; van Grunsven, Leo A; Canbay, Ali

    2015-02-01

    During massive liver injury and hepatocyte loss, the intrinsic regenerative capacity of the liver by replication of resident hepatocytes is overwhelmed. Treatment of this condition depends on the cause of liver injury, though in many cases liver transplantation (LT) remains the only curative option. LT for end stage chronic and acute liver diseases is hampered by shortage of donor organs and requires immunosuppression. Hepatocyte transplantation is limited by yet unresolved technical difficulties. Since currently no treatment is available to facilitate liver regeneration directly, therapies involving the use of resident liver stem or progenitor cells (LPCs) or non-liver stem cells are coming to fore. LPCs are quiescent in the healthy liver, but may be activated under conditions where the regenerative capacity of mature hepatocytes is severely impaired. Non-liver stem cells include embryonic stem cells (ES cells) and mesenchymal stem cells (MSCs). In the first section, we aim to provide an overview of the role of putative cytokines, growth factors, mitogens and hormones in regulating LPC response and briefly discuss the prognostic value of the LPC response in clinical practice. In the latter section, we will highlight the role of other (non-liver) stem cells in transplantation and discuss advantages and disadvantages of ES cells, induced pluripotent stem cells (iPS), as well as MSCs.

  20. Binary progenitor models of type IIb supernovae

    CERN Document Server

    Claeys, J S W; Pols, O R; Eldridge, J J; Baes, M

    2011-01-01

    Massive stars that lose their hydrogen-rich envelope down to a few tenths of a solar mass explode as extended type IIb supernovae, an intriguing subtype that links the hydrogen-rich type II supernovae with the hydrogen-poor type Ib and Ic. The progenitors may be very massive single stars that lose their envelope due to their stellar wind, but mass stripping due to interaction with a companion star in a binary system is currently considered to be the dominant formation channel. We computed an extensive grid of binary models with the Eggleton binary evolution code. The predicted rate from our standard models, which assume conservative mass transfer, is about 6 times smaller than the current rate indicated by observations. It is larger but still comparable to the rate expected from single stars. To recover the observed rate we must generously allow for uncertainties and low accretion efficiencies in combination with limited angular momentum loss from the system. Motivated by the claims of detection and non-detec...

  1. Subretinal transplantation of mouse retinal progenitor cells

    Institute of Scientific and Technical Information of China (English)

    Caihui Jiang; Maonian Zhang; Henry Klassen; Michael Young

    2011-01-01

    The development of cell replacement techniques is promising as a potential treatment for photoreceptor loss. However, the limited integration ability of donor and recipient cells presents a challenge following transplantation. In the present study, retinal progenitor cells (RPCs) were harvested from the neural retinas of enhanced green fluorescent protein mice on postnatal day 1, and expanded in a neurobasal medium supplemented with fetal bovine serum without endothelial growth factor. Using a confocal microscope, immunohistochemistry demonstrated that expanded RPCs in vitro maintain retinal stem cell properties and can be differentiated into photoreceptor cells. Three weeks after transplantation, subretinal transplanted RPCs were found to have migrated and integrated into the outer nuclear layer of recipient retinas with laser injury, some of the integrated cells had differentiated into photoreceptors, and a subpopulation of these cells expressed photoreceptor specific synaptic protein, appearing to form synaptic connections with bipolar cells. These results suggest that subretinal transplantation of RPCs may provide a feasible therapeutic strategy for the loss of retinal photoreceptor cells.

  2. Hepatic progenitors for liver disease: current position

    Directory of Open Access Journals (Sweden)

    Alice Conigliaro

    2010-02-01

    Full Text Available Alice Conigliaro1, David A Brenner2, Tatiana Kisseleva21University “La Sapienza”, Dipartimento di Biotecnologie Cellulari ed Ematologia Policlinico Umberto I, V Clinica Medica, Rome, Italy; 2Department of Medicine, University of California, San Diego, La Jolla, CA, USAAbstract: Liver regeneration restores the original functionality of hepatocytes and cholangiocytes in response to injury. It is regulated on several levels, with different cellular populations contributing to this process, eg, hepatocytes, liver precursor cells, intrahepatic stem cells. In response to injury, mature hepatocytes have the capability to proliferate and give rise to new hepatocytes and cholangiocytes. Meanwhile, liver precursor cells (oval cells have become the most recognized bipotential precursor cells in the damaged liver. They rapidly proliferate, change their cellular composition, and differentiate into hepatocytes and cholangiocytes to compensate for the cellular loss and maintain liver homeostasis. There is a growing body of evidence that oval cells originate from the intrahepatic stem cell(s, which in turn give(s rise to epithelial, including oval cells, and/or other hepatic cells of nonepithelial origin. Since there is a close relationship between the liver and hematopoiesis, bone marrow derived cells can also contribute to liver regeneration by the fusion of myeloid cells with damaged hepatocytes, or differentiation of mesenchymal stem cells into hepatocyte-like cells. The current review discusses the contribution of different cells to liver regeneration and their characteristics.Keywords: hepatic progenitor, liver disease, liver precursor cells, oval cells, hepatocytes, intrahepatic stem cells, cholangiocytes

  3. Type Ia Supernovae: Colors, Rates, and Progenitors

    CERN Document Server

    Heringer, Epson; Kezwer, Jason; Graham, Melissa L; Sand, David; Bildfell, Chris

    2016-01-01

    The rate of type Ia supernovae (SNe Ia) in a galaxy depends not only on stellar mass, but also on star formation history. Here we show that two simple observational quantities ($g-r$ or $u-r$ host galaxy color, and $r$-band luminosity), coupled with an assumed delay time distribution (the rate of SNe Ia as a function of time for an instantaneous burst of star formation), are sufficient to accurately determine a galaxy's SN Ia rate, with very little sensitivity to the precise details of the star formation history. Using this result, we compare observed and predicted color distributions of SN Ia hosts for the MENeaCS cluster supernova survey, and for the SDSS Stripe 82 supernova survey. The observations are consistent with a continuous delay time distribution (DTD), without any cutoff. For old progenitor systems the power-law slope for the DTD is found to be $-1.50 ^{+0.19} _{-0.15}$. This result favours the double degenerate scenario for SN Ia, though other interpretations are possible. We find that the late-t...

  4. Constraining GRB progenitors environment with Swift XRT

    CERN Document Server

    Saez, Dounia

    2015-01-01

    The characteristics of the Gamma-Ray Bursts (GRBs) environment may reflect the differences in GRB progenitors: long GRBs are expected to be found in high-density star-forming regions of the GRB host galaxies, while short ones may be associated with an older stellar population that may have had the time to travel far from stellar forming regions in potentially lower density regions. The latter is related to the hypothesis that short GRBs are associated to the merging of compact objects (BH-NS or NS-NS). We used the Swift XRT GRB afterglow archive to compare the intrinsic neutral hydrogen column density values for long and short GRBs within the redshift range 0.1- 1.3, performing a coherent analysis, and excluding from our analysis observations with poor statistics, which reduced our sample to 15 short GRBs. While short GRBs effectively show a median absorption value smaller than long ones the result is not statistically significant. In order to increase our sample we added short GRBs without redshift measure, ...

  5. The Hippo pathway controls a switch between retinal progenitor cell proliferation and photoreceptor cell differentiation in zebrafish.

    Science.gov (United States)

    Asaoka, Yoichi; Hata, Shoji; Namae, Misako; Furutani-Seiki, Makoto; Nishina, Hiroshi

    2014-01-01

    The precise regulation of numbers and types of neurons through control of cell cycle exit and terminal differentiation is an essential aspect of neurogenesis. The Hippo signaling pathway has recently been identified as playing a crucial role in promoting cell cycle exit and terminal differentiation in multiple types of stem cells, including in retinal progenitor cells. When Hippo signaling is activated, the core Mst1/2 kinases activate the Lats1/2 kinases, which in turn phosphorylate and inhibit the transcriptional cofactor Yap. During mouse retinogenesis, overexpression of Yap prolongs progenitor cell proliferation, whereas inhibition of Yap decreases this proliferation and promotes retinal cell differentiation. However, to date, it remains unknown how the Hippo pathway affects the differentiation of distinct neuronal cell types such as photoreceptor cells. In this study, we investigated whether Hippo signaling regulates retinogenesis during early zebrafish development. Knockdown of zebrafish mst2 induced early embryonic defects, including altered retinal pigmentation and morphogenesis. Similar abnormal retinal phenotypes were observed in zebrafish embryos injected with a constitutively active form of yap [(yap (5SA)]. Loss of Yap's TEAD-binding domain, two WW domains, or transcription activation domain attenuated the retinal abnormalities induced by yap (5SA), indicating that all of these domains contribute to normal retinal development. Remarkably, yap (5SA)-expressing zebrafish embryos displayed decreased expression of transcription factors such as otx5 and crx, which orchestrate photoreceptor cell differentiation by activating the expression of rhodopsin and other photoreceptor cell genes. Co-immunoprecipitation experiments revealed that Rx1 is a novel interacting partner of Yap that regulates photoreceptor cell differentiation. Our results suggest that Yap suppresses the differentiation of photoreceptor cells from retinal progenitor cells by repressing Rx1

  6. The Hippo pathway controls a switch between retinal progenitor cell proliferation and photoreceptor cell differentiation in zebrafish.

    Directory of Open Access Journals (Sweden)

    Yoichi Asaoka

    Full Text Available The precise regulation of numbers and types of neurons through control of cell cycle exit and terminal differentiation is an essential aspect of neurogenesis. The Hippo signaling pathway has recently been identified as playing a crucial role in promoting cell cycle exit and terminal differentiation in multiple types of stem cells, including in retinal progenitor cells. When Hippo signaling is activated, the core Mst1/2 kinases activate the Lats1/2 kinases, which in turn phosphorylate and inhibit the transcriptional cofactor Yap. During mouse retinogenesis, overexpression of Yap prolongs progenitor cell proliferation, whereas inhibition of Yap decreases this proliferation and promotes retinal cell differentiation. However, to date, it remains unknown how the Hippo pathway affects the differentiation of distinct neuronal cell types such as photoreceptor cells. In this study, we investigated whether Hippo signaling regulates retinogenesis during early zebrafish development. Knockdown of zebrafish mst2 induced early embryonic defects, including altered retinal pigmentation and morphogenesis. Similar abnormal retinal phenotypes were observed in zebrafish embryos injected with a constitutively active form of yap [(yap (5SA]. Loss of Yap's TEAD-binding domain, two WW domains, or transcription activation domain attenuated the retinal abnormalities induced by yap (5SA, indicating that all of these domains contribute to normal retinal development. Remarkably, yap (5SA-expressing zebrafish embryos displayed decreased expression of transcription factors such as otx5 and crx, which orchestrate photoreceptor cell differentiation by activating the expression of rhodopsin and other photoreceptor cell genes. Co-immunoprecipitation experiments revealed that Rx1 is a novel interacting partner of Yap that regulates photoreceptor cell differentiation. Our results suggest that Yap suppresses the differentiation of photoreceptor cells from retinal progenitor cells by

  7. Cajal bodies in neurons.

    Science.gov (United States)

    Lafarga, Miguel; Tapia, Olga; Romero, Ana M; Berciano, Maria T

    2016-09-14

    Cajal is commonly regarded as the father of modern neuroscience in recognition of his fundamental work on the structure of the nervous system. But Cajal also made seminal contributions to the knowledge of nuclear structure in the early 1900s, including the discovery of the "accessory body" later renamed "Cajal body" (CB). This important nuclear structure has emerged as a center for the assembly of ribonucleoproteins (RNPs) required for splicing, ribosome biogenesis and telomere maintenance. The modern era of CB research started in the 1990s with the discovery of coilin, now known as a scaffold protein of CBs, and specific probes for small nuclear RNAs (snRNAs). In this review, we summarize what we have learned in the recent decades concerning CBs in post-mitotic neurons, thereby ruling out dynamic changes in CB functions during the cell cycle. We show that CBs are particularly prominent in neurons, where they frequently associate with the nucleolus. Neuronal CBs are transcription-dependent nuclear organelles. Indeed, their number dynamically accommodates to support the high neuronal demand for splicing and ribosome biogenesis required for sustaining metabolic and bioelectrical activity. Mature neurons have canonical CBs enriched in coilin, survival motor neuron protein and snRNPs. Disruption and loss of neuronal CBs associate with severe neuronal dysfunctions in several neurological disorders such as motor neuron diseases. In particular, CB depletion in motor neurons seems to reflect a perturbation of transcription and splicing in spinal muscular atrophy, the most common genetic cause of infant mortality.

  8. The Bicoid class homeodomain factors ceh-36/OTX and unc-30/PITX cooperate in C. elegans embryonic progenitor cells to regulate robust development.

    Directory of Open Access Journals (Sweden)

    Travis Walton

    2015-03-01

    Full Text Available While many transcriptional regulators of pluripotent and terminally differentiated states have been identified, regulation of intermediate progenitor states is less well understood. Previous high throughput cellular resolution expression studies identified dozens of transcription factors with lineage-specific expression patterns in C. elegans embryos that could regulate progenitor identity. In this study we identified a broad embryonic role for the C. elegans OTX transcription factor ceh-36, which was previously shown to be required for the terminal specification of four neurons. ceh-36 is expressed in progenitors of over 30% of embryonic cells, yet is not required for embryonic viability. Quantitative phenotyping by computational analysis of time-lapse movies of ceh-36 mutant embryos identified cell cycle or cell migration defects in over 100 of these cells, but most defects were low-penetrance, suggesting redundancy. Expression of ceh-36 partially overlaps with that of the PITX transcription factor unc-30. unc-30 single mutants are viable but loss of both ceh-36 and unc-30 causes 100% lethality, and double mutants have significantly higher frequencies of cellular developmental defects in the cells where their expression normally overlaps. These factors are also required for robust expression of the downstream developmental regulator mls-2/HMX. This work provides the first example of genetic redundancy between the related yet evolutionarily distant OTX and PITX families of bicoid class homeodomain factors and demonstrates the power of quantitative developmental phenotyping in C. elegans to identify developmental regulators acting in progenitor cells.

  9. Varicella Zoster Virus (VZV-Human Neuron Interaction

    Directory of Open Access Journals (Sweden)

    Don Gilden

    2013-09-01

    Full Text Available Varicella zoster virus (VZV is a highly neurotropic, exclusively human herpesvirus. Primary infection causes varicella (chickenpox, wherein VZV replicates in multiple organs, particularly the skin. Widespread infection in vivo is confirmed by the ability of VZV to kill tissue culture cells in vitro derived from any organ. After varicella, VZV becomes latent in ganglionic neurons along the entire neuraxis. During latency, virus DNA replication stops, transcription is restricted, and no progeny virions are produced, indicating a unique virus-cell (neuron relationship. VZV reactivation produces zoster (shingles, often complicated by serious neurological and ocular disorders. The molecular trigger(s for reactivation, and thus the identity of a potential target to prevent it, remains unknown due to an incomplete understanding of the VZV-neuron interaction. While no in vitro system has yet recapitulated the findings in latently infected ganglia, recent studies show that VZV infection of human neurons in SCID mice and of human stem cells, including induced human pluripotent stem cells and normal human neural progenitor tissue-like assemblies, can be established in the absence of a cytopathic effect. Usefulness of these systems in discovering the mechanisms underlying reactivation awaits analyses of VZV-infected, highly pure (>90%, terminally differentiated human neurons capable of prolonged survival in vitro.

  10. Lithium promotes neuronal repair and ameliorates depression-like behavior following trimethyltin-induced neuronal loss in the dentate gyrus.

    Science.gov (United States)

    Yoneyama, Masanori; Shiba, Tatsuo; Hasebe, Shigeru; Umeda, Kasumi; Yamaguchi, Taro; Ogita, Kiyokazu

    2014-01-01

    Lithium, a mood stabilizer, is known to ameliorate the stress-induced decrease in hippocampal neurogenesis seen in animal models of stress-related disorders. However, it is unclear whether lithium has beneficial effect on neuronal repair following neuronal damage in neuronal degenerative diseases. Here, we evaluated the effect of in vivo treatment with lithium on the hippocampal neuronal repair in a mouse model of trimethyltin (TMT)-induced neuronal loss/self-repair in the hippocampal dentate gyrus (such mice referred to as "impaired animals") [Ogita et al. (2005) J Neurosci Res 82: 609-621]. The impaired animals had a dramatically increased number of 5-bromo-2'-deoxyuridine (BrdU)-incorporating cells in their dentate gyrus at the initial time window (days 3 to 5 post-TMT treatment) of the self-repair stage. A single treatment with lithium produced no significant change in the number of BrdU-incorporating cells in the dentate granule cell layer and subgranular zone on day 3 post-TMT treatment. On day 5 post-TMT treatment, however, BrdU-incorporating cells were significantly increased in number by lithium treatment for 3 days. Most interestingly, chronic treatment (15 days) with lithium increased the number of BrdU-incorporating cells positive for NeuN or doublecortin in the dentate granule cell layer of the impaired animals, but not in that of naïve animals. The results of a forced swimming test revealed that the chronic treatment with lithium improved the depression-like behavior seen in the impaired animals. Taken together, our data suggest that lithium had a beneficial effect on neuronal repair following neuronal loss in the dentate gyrus through promoted proliferation and survival/neuronal differentiation of neural stem/progenitor cells in the subgranular zone.

  11. Lithium promotes neuronal repair and ameliorates depression-like behavior following trimethyltin-induced neuronal loss in the dentate gyrus.

    Directory of Open Access Journals (Sweden)

    Masanori Yoneyama

    Full Text Available Lithium, a mood stabilizer, is known to ameliorate the stress-induced decrease in hippocampal neurogenesis seen in animal models of stress-related disorders. However, it is unclear whether lithium has beneficial effect on neuronal repair following neuronal damage in neuronal degenerative diseases. Here, we evaluated the effect of in vivo treatment with lithium on the hippocampal neuronal repair in a mouse model of trimethyltin (TMT-induced neuronal loss/self-repair in the hippocampal dentate gyrus (such mice referred to as "impaired animals" [Ogita et al. (2005 J Neurosci Res 82: 609-621]. The impaired animals had a dramatically increased number of 5-bromo-2'-deoxyuridine (BrdU-incorporating cells in their dentate gyrus at the initial time window (days 3 to 5 post-TMT treatment of the self-repair stage. A single treatment with lithium produced no significant change in the number of BrdU-incorporating cells in the dentate granule cell layer and subgranular zone on day 3 post-TMT treatment. On day 5 post-TMT treatment, however, BrdU-incorporating cells were significantly increased in number by lithium treatment for 3 days. Most interestingly, chronic treatment (15 days with lithium increased the number of BrdU-incorporating cells positive for NeuN or doublecortin in the dentate granule cell layer of the impaired animals, but not in that of naïve animals. The results of a forced swimming test revealed that the chronic treatment with lithium improved the depression-like behavior seen in the impaired animals. Taken together, our data suggest that lithium had a beneficial effect on neuronal repair following neuronal loss in the dentate gyrus through promoted proliferation and survival/neuronal differentiation of neural stem/progenitor cells in the subgranular zone.

  12. Apoptosis of glutamatergic neurons fails to trigger a neurogenic response in the adult neocortex.

    Science.gov (United States)

    Diaz, Frank; McKeehan, Nicholas; Kang, Wenfei; Hébert, Jean M

    2013-04-10

    Adult neurogenesis is actively studied in part because of the potential to manipulate endogenous neural stem and progenitor cells for tissue repair. Although constitutive generation of neurons in the adult rodent olfactory bulb and hippocampal dentate gyrus is widely accepted and stroke-induced generation of striatal inhibitory neurons consistently observed, evidence supporting the generation of neurons in the neocortex after neuronal loss remains slim. Nevertheless, a few studies suggested that targeted apoptosis of neocortical glutamatergic neurons could trigger the generation of new ones in the adult brain. In light of such studies, we tested whether apoptosis of glutamatergic cortical neurons using two novel transgenic approaches in mice, an inducible Caspase-8 protein and an inducible diphtheria toxin gene, results in new neurons. After a thorough analysis, no new neurons were detected in the neocortex. Interestingly, an increase in the expression of the neuroblast marker DCX was observed in both models, in some cases in cells with morphologies previously associated with poststroke neuroblasts, but DCX(+) cells coexpressed the oligodendrocyte precursor marker Olig2, suggesting caution when using DCX as a marker for neuroblasts after injury. Given that the adult neocortex lacks an innate potential to regenerate lost glutamatergic neurons, future strategies should concentrate on manipulating the differentiation potential of endogenous or exogenous precursor cells.

  13. Pbx Regulates Patterning of the Cerebral Cortex in Progenitors and Postmitotic Neurons

    DEFF Research Database (Denmark)

    Golonzhka, Olga; Nord, Alex; Tang, Paul L F

    2015-01-01

    molecular phenotypes of cortical regional and laminar organization: hypoplasia of the frontal cortex, ventral expansion of the dorsomedial cortex, and ventral expansion of Reelin expression in the cortical plate of the frontal cortex, concomitant with an inversion of cortical layering in the rostral cortex...

  14. Noise and Neuronal Heterogeneity

    CERN Document Server

    Barber, Michael J

    2010-01-01

    We consider signal transaction in a simple neuronal model featuring intrinsic noise. The presence of noise limits the precision of neural responses and impacts the quality of neural signal transduction. We assess the signal transduction quality in relation to the level of noise, and show it to be maximized by a non-zero level of noise, analogous to the stochastic resonance effect. The quality enhancement occurs for a finite range of stimuli to a single neuron; we show how to construct networks of neurons that extend the range. The range increases more rapidly with network size when we make use of heterogeneous populations of neurons with a variety of thresholds, rather than homogeneous populations of neurons all with the same threshold. The limited precision of neural responses thus can have a direct effect on the optimal network structure, with diverse functional properties of the constituent neurons supporting an economical information processing strategy that reduces the metabolic costs of handling a broad...

  15. Neurons and tumor suppressors.

    Science.gov (United States)

    Zochodne, Douglas W

    2014-08-20

    Neurons choose growth pathways with half hearted reluctance, behavior that may be appropriate to maintain fixed long lasting connections but not to regenerate them. We now recognize that intrinsic brakes on regrowth are widely expressed in these hesitant neurons and include classical tumor suppressor molecules. Here, we review how two brakes, PTEN (phosphatase and tensin homolog deleted on chromosome 10) and retinoblastoma emerge as new and exciting knockdown targets to enhance neuron plasticity and improve outcome from damage or disease.

  16. 2-Bromopalmitate modulates neuronal differentiation through the regulation of histone acetylation

    OpenAIRE

    Chen, Xueran; Du, Zhaoxia; Shi, Wei; Wang, Chen; Yang YANG; Wang, Fen; Yao, Yao; He, Kun; Hao, Aijun

    2014-01-01

    In order to evaluate the functional significance of palmitoylation during multi-potent neural stem/progenitor cell proliferation and differentiation, retinoic acid-induced P19 cells were used in this study as a model system. Cell behaviour was monitored in the presence of the protein palmitoylation inhibitor 2-bromopalmitate (2BP). Here, we observed a significant reduction in neuronal differentiation in the 2BP-treated cell model. We further explored the underlying mechanisms and found that 2...

  17. Cell-Surface Protein Profiling Identifies Distinctive Markers of Progenitor Cells in Human Skeletal Muscle

    Directory of Open Access Journals (Sweden)

    Akiyoshi Uezumi

    2016-08-01

    Full Text Available Skeletal muscle contains two distinct stem/progenitor populations. One is the satellite cell, which acts as a muscle stem cell, and the other is the mesenchymal progenitor, which contributes to muscle pathogeneses such as fat infiltration and fibrosis. Detailed and accurate characterization of these progenitors in humans remains elusive. Here, we performed comprehensive cell-surface protein profiling of the two progenitor populations residing in human skeletal muscle and identified three previously unrecognized markers: CD82 and CD318 for satellite cells and CD201 for mesenchymal progenitors. These markers distinguish myogenic and mesenchymal progenitors, and enable efficient isolation of the two types of progenitors. Functional study revealed that CD82 ensures expansion and preservation of myogenic progenitors by suppressing excessive differentiation, and CD201 signaling favors adipogenesis of mesenchymal progenitors. Thus, cell-surface proteins identified here are not only useful markers but also functionally important molecules, and provide valuable insight into human muscle biology and diseases.

  18. Indian hedgehog B function is required for the specification of oligodendrocyte progenitor cells in the zebrafish CNS.

    Science.gov (United States)

    Chung, Ah-Young; Kim, Suhyun; Kim, Eunmi; Kim, Dohyun; Jeong, Inyoung; Cha, Young Ryun; Bae, Young-ki; Park, Seung Woo; Lee, Jehee; Park, Hae-Chul

    2013-01-23

    A subset of ventral spinal cord precursors, known as pMN precursor cells, initially generate motor neurons and then oligodendrocyte progenitor cells (OPCs), which migrate and differentiate as myelinating oligodendrocytes in the developing neural tube. The switch between motor neuron and oligodendrocyte production by the pMN neural precursors is an important step in building a functional nervous system. However, the precise mechanism that orchestrates the sequential generation of motor neurons and oligodendrocytes within the common population of pMN precursors is still unclear. The current study demonstrates that Indian Hedgehog b (Ihhb), previously known as Echidna Hedgehog, begins to be expressed in the floor plate cells of the ventral spinal cord at the time of OPC specification in zebrafish embryos. Ihhb loss-of-function analysis revealed that Ihhb function is required for OPC specification from pMN precursors by negatively regulating the proliferation of neural precursors. Finally, results showed that Sonic Hedgehog (Shh) could not replace Ihhb function in OPC specification, suggesting that Ihhb and Shh play separate roles in OPC specification. Altogether, data from the present study suggested a novel mechanism, mediated by Ihhb, for the sequential generation of motor neurons and oligodendrocytes from pMN precursors in the ventral spinal cord of zebrafish embryos.

  19. Three-dimensional normal human neural progenitor tissue-like assemblies: a model of persistent varicella-zoster virus infection.

    Directory of Open Access Journals (Sweden)

    Thomas J Goodwin

    Full Text Available Varicella-zoster virus (VZV is a neurotropic human alphaherpesvirus that causes varicella upon primary infection, establishes latency in multiple ganglionic neurons, and can reactivate to cause zoster. Live attenuated VZV vaccines are available; however, they can also establish latent infections and reactivate. Studies of VZV latency have been limited to the analyses of human ganglia removed at autopsy, as the virus is strictly a human pathogen. Recently, terminally differentiated human neurons have received much attention as a means to study the interaction between VZV and human neurons; however, the short life-span of these cells in culture has limited their application. Herein, we describe the construction of a model of normal human neural progenitor cells (NHNP in tissue-like assemblies (TLAs, which can be successfully maintained for at least 180 days in three-dimensional (3D culture, and exhibit an expression profile similar to that of human trigeminal ganglia. Infection of NHNP TLAs with cell-free VZV resulted in a persistent infection that was maintained for three months, during which the virus genome remained stable. Immediate-early, early and late VZV genes were transcribed, and low-levels of infectious VZV were recurrently detected in the culture supernatant. Our data suggest that NHNP TLAs are an effective system to investigate long-term interactions of VZV with complex assemblies of human neuronal cells.

  20. Three-dimensional normal human neural progenitor tissue-like assemblies: a model of persistent varicella-zoster virus infection.

    Science.gov (United States)

    Goodwin, Thomas J; McCarthy, Maureen; Osterrieder, Nikolaus; Cohrs, Randall J; Kaufer, Benedikt B

    2013-01-01

    Varicella-zoster virus (VZV) is a neurotropic human alphaherpesvirus that causes varicella upon primary infection, establishes latency in multiple ganglionic neurons, and can reactivate to cause zoster. Live attenuated VZV vaccines are available; however, they can also establish latent infections and reactivate. Studies of VZV latency have been limited to the analyses of human ganglia removed at autopsy, as the virus is strictly a human pathogen. Recently, terminally differentiated human neurons have received much attention as a means to study the interaction between VZV and human neurons; however, the short life-span of these cells in culture has limited their application. Herein, we describe the construction of a model of normal human neural progenitor cells (NHNP) in tissue-like assemblies (TLAs), which can be successfully maintained for at least 180 days in three-dimensional (3D) culture, and exhibit an expression profile similar to that of human trigeminal ganglia. Infection of NHNP TLAs with cell-free VZV resulted in a persistent infection that was maintained for three months, during which the virus genome remained stable. Immediate-early, early and late VZV genes were transcribed, and low-levels of infectious VZV were recurrently detected in the culture supernatant. Our data suggest that NHNP TLAs are an effective system to investigate long-term interactions of VZV with complex assemblies of human neuronal cells.

  1. The Lysine Acetyltransferase Activator Brpf1 Governs Dentate Gyrus Development through Neural Stem Cells and Progenitors

    Science.gov (United States)

    You, Linya; Yan, Kezhi; Zhou, Jinfeng; Zhao, Hong; Bertos, Nicholas R.; Park, Morag; Wang, Edwin; Yang, Xiang-Jiao

    2015-01-01

    Lysine acetylation has recently emerged as an important post-translational modification in diverse organisms, but relatively little is known about its roles in mammalian development and stem cells. Bromodomain- and PHD finger-containing protein 1 (BRPF1) is a multidomain histone binder and a master activator of three lysine acetyltransferases, MOZ, MORF and HBO1, which are also known as KAT6A, KAT6B and KAT7, respectively. While the MOZ and MORF genes are rearranged in leukemia, the MORF gene is also mutated in prostate and other cancers and in four genetic disorders with intellectual disability. Here we show that forebrain-specific inactivation of the mouse Brpf1 gene causes hypoplasia in the dentate gyrus, including underdevelopment of the suprapyramidal blade and complete loss of the infrapyramidal blade. We trace the developmental origin to compromised Sox2+ neural stem cells and Tbr2+ intermediate neuronal progenitors. We further demonstrate that Brpf1 loss deregulates neuronal migration, cell cycle progression and transcriptional control, thereby causing abnormal morphogenesis of the hippocampus. These results link histone binding and acetylation control to hippocampus development and identify an important epigenetic regulator for patterning the dentate gyrus, a brain structure critical for learning, memory and adult neurogenesis. PMID:25757017

  2. Methylglyoxal Causes Cell Death in Neural Progenitor Cells and Impairs Adult Hippocampal Neurogenesis.

    Science.gov (United States)

    Chun, Hye Jeong; Lee, Yujeong; Kim, Ah Hyun; Lee, Jaewon

    2016-04-01

    Methylglyoxal (MG) is formed during normal metabolism by processes like glycolysis, lipid peroxidation, and threonine catabolism, and its accumulation is associated with various degenerative diseases, such as diabetes and arterial atherogenesis. Furthermore, MG has also been reported to have toxic effects on hippocampal neurons. However, these effects have not been studied in the context of neurogenesis. Here, we report that MG adversely affects hippocampal neurogenesis and induces neural progenitor cell (NPC) death. MG significantly reduced C17.2 NPC proliferation, and high concentration of MG (500 μM) induced cell death and elevated oxidative stress. Further, MG was found to activate the ERK signaling pathway, indicating elevated stress response. To determine the effects of MG in vivo, mice were administrated with vehicle or MG (0.5 or 1 % in drinking water) for 4 weeks. The numbers of BrdU-positive cells in hippocampi were significantly lower in MG-treated mice, indicating impaired neurogenesis, but MG did not induce neuronal damage or glial activations. Interestingly, MG reduced memory retention when administered to mice at 1 % but not at 0.5 %. In addition, the levels of hippocampal BDNF and synaptophysin were significantly lower in the hippocampi of mice treated with MG at 1 %. Collectively, our findings suggest MG could be harmful to NPCs and to hippocampal neurogenesis.

  3. Generation of Integration-free and Region-Specific Neural Progenitors from Primate Fibroblasts

    Directory of Open Access Journals (Sweden)

    Jianfeng Lu

    2013-05-01

    Full Text Available Postnatal and adult human and monkey fibroblasts were infected with Sendai virus containing the Yamanaka factors for 24 hr, then they were cultured in a chemically defined medium containing leukemia inhibitory factor (LIF, transforming growth factor (TGF-β inhibitor SB431542, and glycogen synthase kinase (GSK-3β inhibitor CHIR99021 at 39°C for inactivation of the virus. Induced neural progenitor (iNP colonies appeared as early as day 13 and can be expanded for >20 passages. Under the same defined condition, no induced pluripotent stem cell (iPSC colonies formed at either 37°C or 39°C. The iNPs predominantly express hindbrain genes and differentiate into hindbrain neurons, and when caudalized, they produced an enriched population of spinal motor neurons. Following transplantation into the forebrain, the iNP-derived cells retained the hindbrain identity. The ability to generate defined, integration-free iNPs from adult primate fibroblasts under a defined condition with predictable fate choices will facilitate disease modeling and therapeutic development.

  4. The lysine acetyltransferase activator Brpf1 governs dentate gyrus development through neural stem cells and progenitors.

    Science.gov (United States)

    You, Linya; Yan, Kezhi; Zou, Jinfeng; Zhou, Jinfeng; Zhao, Hong; Bertos, Nicholas R; Park, Morag; Wang, Edwin; Yang, Xiang-Jiao

    2015-03-01

    Lysine acetylation has recently emerged as an important post-translational modification in diverse organisms, but relatively little is known about its roles in mammalian development and stem cells. Bromodomain- and PHD finger-containing protein 1 (BRPF1) is a multidomain histone binder and a master activator of three lysine acetyltransferases, MOZ, MORF and HBO1, which are also known as KAT6A, KAT6B and KAT7, respectively. While the MOZ and MORF genes are rearranged in leukemia, the MORF gene is also mutated in prostate and other cancers and in four genetic disorders with intellectual disability. Here we show that forebrain-specific inactivation of the mouse Brpf1 gene causes hypoplasia in the dentate gyrus, including underdevelopment of the suprapyramidal blade and complete loss of the infrapyramidal blade. We trace the developmental origin to compromised Sox2+ neural stem cells and Tbr2+ intermediate neuronal progenitors. We further demonstrate that Brpf1 loss deregulates neuronal migration, cell cycle progression and transcriptional control, thereby causing abnormal morphogenesis of the hippocampus. These results link histone binding and acetylation control to hippocampus development and identify an important epigenetic regulator for patterning the dentate gyrus, a brain structure critical for learning, memory and adult neurogenesis.

  5. The lysine acetyltransferase activator Brpf1 governs dentate gyrus development through neural stem cells and progenitors.

    Directory of Open Access Journals (Sweden)

    Linya You

    2015-03-01

    Full Text Available Lysine acetylation has recently emerged as an important post-translational modification in diverse organisms, but relatively little is known about its roles in mammalian development and stem cells. Bromodomain- and PHD finger-containing protein 1 (BRPF1 is a multidomain histone binder and a master activator of three lysine acetyltransferases, MOZ, MORF and HBO1, which are also known as KAT6A, KAT6B and KAT7, respectively. While the MOZ and MORF genes are rearranged in leukemia, the MORF gene is also mutated in prostate and other cancers and in four genetic disorders with intellectual disability. Here we show that forebrain-specific inactivation of the mouse Brpf1 gene causes hypoplasia in the dentate gyrus, including underdevelopment of the suprapyramidal blade and complete loss of the infrapyramidal blade. We trace the developmental origin to compromised Sox2+ neural stem cells and Tbr2+ intermediate neuronal progenitors. We further demonstrate that Brpf1 loss deregulates neuronal migration, cell cycle progression and transcriptional control, thereby causing abnormal morphogenesis of the hippocampus. These results link histone binding and acetylation control to hippocampus development and identify an important epigenetic regulator for patterning the dentate gyrus, a brain structure critical for learning, memory and adult neurogenesis.

  6. Interleukin-1 regulates proliferation and differentiation of oligodendrocyte progenitor cells.

    Science.gov (United States)

    Vela, José M; Molina-Holgado, Eduardo; Arévalo-Martín, Angel; Almazán, Guillermina; Guaza, Carmen

    2002-07-01

    Interleukin-1 (IL-1) is a pleiotropic cytokine expressed during normal CNS development and in inflammatory demyelinating diseases, but remarkably little is known about its effect on oligodendroglial cells. In this study we explored the role of IL-1beta in oligodendrocyte progenitors and differentiated oligodendrocytes. The effects of IL-1beta were compared to those of IL-1 receptor antagonist, the specific inhibitor of IL-1 activity, since progenitors and differentiated oligodendrocytes produce IL-1beta and express IL-1 receptors. Unlike other proinflammatory cytokines (TNFalpha and IFNgamma), IL-1beta was not toxic for oligodendrocyte lineage cells. However, this cytokine inhibited proliferation of oligodendrocyte progenitors in the presence of growth factors (PDGF plus bFGF). This was evidenced by a significant decrease in both cells incorporating bromodeoxyuridine (45%) and total cell numbers (57%) after 6 days of treatment. Interestingly, IL-1beta blocked proliferation at the late progenitor/prooligodendrocyte (O4+) stage but did not affect proliferation of early progenitors (A2B5+). Inhibition of proliferation paralleled with promotion of differentiation, as revealed by the increased percentage of R-mab+ cells (6.7-fold). Moreover, when oligodendrocyte progenitors were allowed to differentiate in the absence of growth factors, treatment with IL-1beta promoted maturation to the MBP+ stage (4.2-fold) and survival of differentiating oligodendrocytes (2.1-fold). Regarding intracellular signaling, IL-1beta activated the p38 mitogen-activated protein kinase (MAPK) but not the p42/p44 MAPK and, when combined with growth factors, intensified p38 activation but inhibited the growth-factor-induced p42/p44 activation. IL-1beta also induced a time-dependent inhibition of PFGF-Ralpha gene expression. These results support a role for IL-1beta in promoting mitotic arrest and differentiation of oligodendrocyte progenitors as well as maturation and survival of differentiating

  7. Epigenetic States of nephron progenitors and epithelial differentiation.

    Science.gov (United States)

    Adli, Mazhar; Parlak, Mahmut; Li, Yuwen; El-Dahr, Samir S

    2015-06-01

    In mammals, formation of new nephrons ends perinatally due to consumption of mesenchymal progenitor cells. Premature depletion of progenitors due to prematurity or postnatal loss of nephrons due to injury causes chronic kidney disease and hypertension. Intensive efforts are currently invested in designing regenerative strategies to form new nephron progenitors from pluripotent cells, which upon further differentiation provide a potential source of new nephrons. To know if reprogramed renal cells can maintain their identity and fate requires knowledge of the epigenetic states of native nephron progenitors and their progeny. In this article, we summarize current knowledge and gaps in the epigenomic landscape of the developing kidney. We now know that Pax2/PTIP/H3K4 methyltransferase activity provides the initial epigenetic specification signal to the metanephric mesenchyme. During nephrogenesis, the cap mesenchyme housing nephron progenitors is enriched in bivalent chromatin marks; as tubulogenesis proceeds, the tubular epithelium acquires H3K79me2. The latter mark is uniquely induced during epithelial differentiation. Analysis of histone landscapes in clonal metanephric mesenchyme cell lines and in Wilms tumor and normal fetal kidney has revealed that promoters of poised nephrogenesis genes carry bivalent histone signatures in progenitors. Differentiation or stimulation of Wnt signaling promotes resolution of bivalency; this does not occur in Wilms tumor cells consistent with their developmental arrest. The use of small cell number ChIP-Seq should facilitate the characterization of the chromatin landscape of the metanephric mesenchyme and various nephron compartments during nephrogenesis. Only then we will know if stem and somatic cell reprogramming into kidney progenitors recapitulates normal development. © 2015 Wiley Periodicals, Inc.

  8. Retinoic acid from the meninges regulates cortical neuron generation.

    Science.gov (United States)

    Siegenthaler, Julie A; Ashique, Amir M; Zarbalis, Konstantinos; Patterson, Katelin P; Hecht, Jonathan H; Kane, Maureen A; Folias, Alexandra E; Choe, Youngshik; May, Scott R; Kume, Tsutomu; Napoli, Joseph L; Peterson, Andrew S; Pleasure, Samuel J

    2009-10-30

    Extrinsic signals controlling generation of neocortical neurons during embryonic life have been difficult to identify. In this study we demonstrate that the dorsal forebrain meninges communicate with the adjacent radial glial endfeet and influence cortical development. We took advantage of Foxc1 mutant mice with defects in forebrain meningeal formation. Foxc1 dosage and loss of meninges correlated with a dramatic reduction in both neuron and intermediate progenitor production and elongation of the neuroepithelium. Several types of experiments demonstrate that retinoic acid (RA) is the key component of this secreted activity. In addition, Rdh10- and Raldh2-expressing cells in the dorsal meninges were either reduced or absent in the Foxc1 mutants, and Rdh10 mutants had a cortical phenotype similar to the Foxc1 null mutants. Lastly, in utero RA treatment rescued the cortical phenotype in Foxc1 mutants. These results establish RA as a potent, meningeal-derived cue required for successful corticogenesis.

  9. Endothelial progenitor cells and integrins: adhesive needs

    Directory of Open Access Journals (Sweden)

    Caiado Francisco

    2012-03-01

    Full Text Available Abstract In the last decade there have been multiple studies concerning the contribution of endothelial progenitor cells (EPCs to new vessel formation in different physiological and pathological settings. The process by which EPCs contribute to new vessel formation in adults is termed postnatal vasculogenesis and occurs via four inter-related steps. They must respond to chemoattractant signals and mobilize from the bone marrow to the peripheral blood; home in on sites of new vessel formation; invade and migrate at the same sites; and differentiate into mature endothelial cells (ECs and/or regulate pre-existing ECs via paracrine or juxtacrine signals. During these four steps, EPCs interact with different physiological compartments, namely bone marrow, peripheral blood, blood vessels and homing tissues. The success of each step depends on the ability of EPCs to interact, adapt and respond to multiple molecular cues. The present review summarizes the interactions between integrins expressed by EPCs and their ligands: extracellular matrix components and cell surface proteins present at sites of postnatal vasculogenesis. The data summarized here indicate that integrins represent a major molecular determinant of EPC function, with different integrin subunits regulating different steps of EPC biology. Specifically, integrin α4β1 is a key regulator of EPC retention and/or mobilization from the bone marrow, while integrins α5β1, α6β1, αvβ3 and αvβ5 are major determinants of EPC homing, invasion, differentiation and paracrine factor production. β2 integrins are the major regulators of EPC transendothelial migration. The relevance of integrins in EPC biology is also demonstrated by many studies that use extracellular matrix-based scaffolds as a clinical tool to improve the vasculogenic functions of EPCs. We propose that targeted and tissue-specific manipulation of EPC integrin-mediated interactions may be crucial to further improve the usage of

  10. P53 regulates disruption of neuronal development in the adult hippocampus after irradiation

    Science.gov (United States)

    Li, Y-Q; Cheng, ZW-C; Liu, SK-W; Aubert, I; Wong, C S

    2016-01-01

    Inhibition of hippocampal neurogenesis is implicated in neurocognitive dysfunction after cranial irradiation for brain tumors. How irradiation results in impaired neuronal development remains poorly understood. The Trp53 (p53) gene is known to regulate cellular DNA damage response after irradiation. Whether it has a role in disruption of late neuronal development remains unknown. Here we characterized the effects of p53 on neuronal development in adult mouse hippocampus after irradiation. Different bromodeoxyuridine incorporation paradigms and a transplantation study were used for cell fate mapping. Compared with wild-type mice, we observed profound inhibition of hippocampal neurogenesis after irradiation in mice deficient in p53 despite the absence of acute apoptosis of neuroblasts. The putative neural stem cells were apoptosis resistant after irradiation regardless of p53 genotype. Cell fate mapping using different bromodeoxyuridine incorporation paradigms revealed enhanced activation of neural stem cells and their consequential exhaustion in the absence of p53 after irradiation. Both p53-knockout and wild-type mice demonstrated similar extent of microglial activation in the hippocampus after irradiation. Impairment of neuronal differentiation of neural progenitors transplanted in irradiated hippocampus was not altered by p53 genotype of the recipient mice. We conclude that by inhibiting neural progenitor activation, p53 serves to mitigate disruption of neuronal development after irradiation independent of apoptosis and perturbation of the neural stem cell niche. These findings suggest for the first time that p53 may have a key role in late effects in brain after irradiation.

  11. ALTERED HIPPOCAMPAL NEUROGENESIS AND AMYGDALAR NEURONAL ACTIVITY IN ADULT MICE WITH REPEATED EXPERIENCE OF AGGRESSION

    Directory of Open Access Journals (Sweden)

    Dmitriy eSmagin

    2015-12-01

    Full Text Available The repeated experience of winning in a social conflict setting elevates levels of aggression and may lead to violent behavioral patterns. Here we use a paradigm of repeated aggression and fighting deprivation to examine changes in behavior, neurogenesis, and neuronal activity in mice with positive fighting experience. We show that for males, repeated positive fighting experience induces persistent demonstration of aggression and stereotypic behaviors in daily agonistic interactions, enhances aggressive motivation, and elevates levels of anxiety. When winning males are deprived of opportunities to engage in further fights, they demonstrate increased levels of aggressiveness. Positive fighting experience results in increased levels of progenitor cell proliferation and production of young neurons in the hippocampus. This increase is not diminished after a fighting deprivation period. Furthermore, repeated winning experience decreases the number of activated (c-fos positive cells in the basolateral amygdala and increases the number of activated cells in the hippocampus; a subsequent no-fight period restores the number of c-fos-positive cells. Our results indicate that extended positive fighting experience in a social conflict heightens aggression, increases proliferation of neuronal progenitors and production of young neurons in the hippocampus, and decreases neuronal activity in the amygdala; these changes can be modified by depriving the winners of the opportunity for further fights.

  12. Motor-circuit communication matrix from spinal cord to brainstem neurons revealed by developmental origin.

    Science.gov (United States)

    Pivetta, Chiara; Esposito, Maria Soledad; Sigrist, Markus; Arber, Silvia

    2014-01-30

    Accurate motor-task execution relies on continuous comparison of planned and performed actions. Motor-output pathways establish internal circuit collaterals for this purpose. Here we focus on motor collateral organization between spinal cord and upstream neurons in the brainstem. We used a newly developed mouse genetic tool intersectionally with viruses to uncover the connectivity rules of these ascending pathways by capturing the transient expression of neuronal subpopulation determinants. We reveal a widespread and diverse network of spinal dual-axon neurons, with coincident input to forelimb motor neurons and the lateral reticular nucleus (LRN) in the brainstem. Spinal information to the LRN is not segregated by motor pool or neurotransmitter identity. Instead, it is organized according to the developmental domain origin of the progenitor cells. Thus, excerpts of most spinal information destined for action are relayed to supraspinal centers through exquisitely organized ascending connectivity modules, enabling precise communication between command and execution centers of movement.

  13. Pacemaking Kisspeptin Neurons

    Science.gov (United States)

    Kelly, Martin J.; Zhang, Chunguang; Qiu, Jian; Rønnekleiv, Oline K.

    2013-01-01

    Kisspeptin (Kiss1) neurons are vital for reproduction. GnRH neurons express the kisspeptin receptor, GPR 54, and kisspeptins potently stimulate the release of GnRH by depolarising and inducing sustained action potential firing in GnRH neurons. As such Kiss1 neurons may be the pre-synaptic pacemaker neurons in the hypothalamic circuitry that controls reproduction. There are at least two different populations of Kiss1 neurons: one in the rostral periventricular area (RP3V) that is stimulated by oestrogens and the other in the arcuate nucleus that is inhibited by oestrogens. How each of these Kiss1 neuronal populations participate in the regulation of the reproductive cycle is currently under intense investigation. Based on electrophysiological studies in the guinea pig and mouse, Kiss1 neurons in general are capable of generating burst firing behavior. Essentially all Kiss1 neurons, which have been studied thus far in the arcuate nucleus, express the ion channels necessary for burst firing, which include hyperpolarization-activated, cyclic nucleotide gated cation (HCN) channels and the T-type calcium (Cav3.1) channels. Under voltage clamp conditions, these channels produce distinct currents that under current clamp conditions can generate burst firing behavior. The future challenge is to identify other key channels and synaptic inputs involved in the regulation of the firing properties of Kiss1 neurons and the physiological regulation of the expression of these channels and receptors by oestrogens and other hormones. The ultimate goal is to understand how Kiss1 neurons control the different phases of GnRH neurosecretion and hence reproduction. PMID:23884368

  14. Chief sources of brachiopod recovery from the end Ordovician mass extinction with special references to progenitors

    Institute of Scientific and Technical Information of China (English)

    戎嘉余; 詹仁斌

    1999-01-01

    Survivor, Lazarus and progenitor taxa are sources of biotic recovery following mass extinction. Investigations of the benthic brachiopods through the latest Ordovician mass extinction shows that progenitors developed many evolutionary novelties and successful surviving mechanisms. They are superior to survivors and Lazarus taxa in their ability to adapt to environmental changes. They are the primary source of macroevolution and the ancestors of a number of new taxa. Three kinds of progenitors are recognized based on the Ordovician-Silurian brachiopods from South China: survivor-progenitors, crisis-progenitors and Lazarus-progenitors; the last has the strongest ability to resist adverse environments, and is the most diverse and abundant.

  15. Ex vivo expansion of human peripheral blood progenitors.

    Science.gov (United States)

    Chabannon, C; Herrera-Rodriguez, D; Bardin, F; Mouren, M; Novakovitch, G; Blaise, D; Maraninchi, D; Mannoni, P

    1995-01-01

    Culture of human hematopoietic progenitors on a large scale could lead to several clinical applications within the near future, including the production of differentiated and functional cells, the increase in the number of early progenitors, especially stem cells, with such use as gene transfer, or the improvement of grafts used to limit the hematological toxicity associated with high-dose chemotherapy. In this case, one can still distinguish different objectives: improvement of grafts that contain low numbers of progenitors because of prior chemotherapies or because of marrow involvement for example, and qualitative changes in the graft content that would allow to envision the disappearance, or the further reduction, in the duration of absolute neutropenia that follows delivery of high dose chemotherapy ("nadir rescue"), despite substitution of mobilized blood cells to marrow cells and the in vivo use of hematopoietic growth factors. Additional advantages may be related to tumor purging in autologous expanded cells, and to the change in the ratio between hematopoietic progenitors and immunocompetent cells in allogeneic expanded populations. Therefore it appears that in vitro expansion currently raises two types of questions: the first ones are related to the definition of clinical or biological endpoints to be achieved, the second ones are related to "bioengineering", and deal with the efficiency and safety of progenitor cell cultures to be used for clinical applications. We here present preliminary results preparing future pilot clinical studies with ex vivo cultured human hematopoietic cells.

  16. Type Ia Supernovae Keep Memory of their Progenitor Metallicity

    Science.gov (United States)

    Piersanti, Luciano; Bravo, Eduardo; Cristallo, Sergio; Domínguez, Inmaculada; Straniero, Oscar; Tornambé, Amedeo; Martínez-Pinedo, Gabriel

    2017-02-01

    The ultimate understanding of SNe Ia diversity is one of the most urgent issues to exploit thermonuclear explosions of accreted White Dwarfs (WDs) as cosmological yardsticks. In particular, we investigate the impact of the progenitor system metallicity on the physical and chemical properties of the WD at the explosion epoch. We analyze the evolution of CO WDs through the accretion and simmering phases by using evolutionary models based on time-dependent convective mixing and an extended nuclear network including the most important electron captures, beta decays, and URCA processes. We find that, due to URCA processes and electron-captures, the neutron excess and density at which the thermal runaway occurs are substantially larger than previously claimed. Moreover, we find that the higher the progenitor metallicity, the larger the neutron excess variation during the accretion and simmering phases and the higher the central density and the convective velocity at the explosion. Hence, the simmering phase acts as an amplifier of the differences existing in SNe Ia progenitors. When applying our results to the neutron excess estimated for the Tycho and Kepler young supernova remnants, we derive that the metallicity of the progenitors should be in the range Z=0.030{--}0.032, close to the average metallicity value of the thin disk of the Milky Way. As the amount of {}56{Ni} produced in the explosion depends on the neutron excess and central density at the thermal runaway, our results suggest that the light curve properties depend on the progenitor metallicity.

  17. The Progenitor of the Type IIb SN 2008ax Revisited

    CERN Document Server

    Folatelli, Gastón; Kuncarayakti, Hanindyo; Benvenuto, Omar G; Maeda, Keiichi; Nomoto, Ken'ichi

    2015-01-01

    Hubble Space Telescope observations of the site of the supernova (SN) 2008ax obtained in 2011 and 2013 reveal that the possible progenitor object detected in pre-explosion images was in fact multiple. Four point sources are resolved in the new, higher-resolution images. We identify one of the sources with the fading SN. The other three objects are consistent with single supergiant stars. We conclude that their light contaminated the previously identified progenitor candidate. After subtraction of these stars, the progenitor appears to be significantly fainter and bluer than previously measured. Post-explosion photometry at the SN location indicates that the progenitor object has disappeared. If single, the progenitor is compatible with a supergiant star of B to mid-A spectral type, while a Wolf-Rayet (WR) star would be too luminous in the ultraviolet to account for the observations. Moreover, our hydrodynamical modelling shows the pre-explosion mass was $4-5$ $M_\\odot$ and the radius was $30-50$ $R_\\odot$, wh...

  18. THE TYPE IIb SUPERNOVA 2011dh FROM A SUPERGIANT PROGENITOR

    Energy Technology Data Exchange (ETDEWEB)

    Bersten, Melina C.; Nomoto, Ken' ichi; Folatelli, Gaston; Maeda, Keiichi [Kavli Institute for the Physics and Mathematics of the Universe, Todai Institutes for Advanced Study, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Benvenuto, Omar G. [Facultad de Ciencias Astronomicas y Geofisicas, Universidad Nacional de La Plata, Paseo del Bosque S/N, B1900FWA La Plata (Argentina); Ergon, Mattias; Sollerman, Jesper [The Oskar Klein Centre, Department of Astronomy, AlbaNova, SE-106 91 Stockholm (Sweden); Benetti, Stefano; Ochner, Paolo; Tomasella, Lina [INAF-Osservatorio Astronomico di Padova, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy); Botticella, Maria Teresa [INAF-Osservatorio Astronomico di Capodimonte, Salita Moiariello 16, I-80131 Napoli (Italy); Fraser, Morgan; Kotak, Rubina, E-mail: melina.bersten@ipmu.jp [Astrophysics Research Centre, School of Mathematics and Physics, Queen' s University Belfast, Belfast BT7 1NN (United Kingdom)

    2012-09-20

    A set of hydrodynamical models based on stellar evolutionary progenitors is used to study the nature of SN 2011dh. Our modeling suggests that a large progenitor star-with R {approx} 200 R{sub Sun }-is needed to reproduce the early light curve (LC) of SN 2011dh. This is consistent with the suggestion that the yellow super-giant star detected at the location of the supernova (SN) in deep pre-explosion images is the progenitor star. From the main peak of the bolometric LC and expansion velocities, we constrain the mass of the ejecta to be Almost-Equal-To 2 M{sub Sun }, the explosion energy to be E = (6-10) Multiplication-Sign 10{sup 50} erg, and the {sup 56}Ni mass to be approximately 0.06 M{sub Sun }. The progenitor star was composed of a helium core of 3-4 M{sub Sun} and a thin hydrogen-rich envelope of Almost-Equal-To 0.1M{sub Sun} with a main-sequence mass estimated to be in the range of 12-15 M{sub Sun }. Our models rule out progenitors with helium-core masses larger than 8 M{sub Sun }, which correspond to M{sub ZAMS} {approx}> 25M{sub Sun }. This suggests that a single star evolutionary scenario for SN 2011dh is unlikely.

  19. The Type IIb Supernova 2011dh from a Supergiant Progenitor

    CERN Document Server

    Bersten, Melina C; Nomoto, Ken'ichi; Ergon, Mattias; Folatelli, Gastón; Sollerman, Jesper; Benetti, Stefano; Botticella, Maria Teresa; Fraser, Morgan; Kotak, Rubina; Maeda, Keiichi; Ochner, Paolo; Tomasella, Lina

    2012-01-01

    A set of hydrodynamical models based on stellar evolutionary progenitors is used to study the nature of SN 2011dh. Our modeling suggests that a large progenitor star ---with R ~200 Rsun---, is needed to reproduce the early light curve of SN 2011dh. This is consistent with the suggestion that the yellow super-giant star detected at the location of the SN in deep pre-explosion images is the progenitor star. From the main peak of the bolometric light curve and expansion velocities we constrain the mass of the ejecta to be ~2 Msun, the explosion energy to be E= 6-10 x 10^50 erg, and the 56Ni mass to be approximately 0.06 Msun. The progenitor star was composed of a helium core of 3 to 4 Msun and a thin hydrogen-rich envelope of ~0.1 M_sun with a main sequence mass estimated to be in the range of 12--15 Msun. Our models rule out progenitors with helium-core masses larger than 8 Msun, which correspond to M_ZAMS > 25 Msun. This suggests that a single star evolutionary scenario for SN 2011dh is unlikely.

  20. The progenitor mass of the magnetar SGR1900+14

    CERN Document Server

    Davies, Ben; Kudritzki, Rolf-Peter; Trombley, Christine; Kouveliotou, Chryssa; Wachter, Stefanie

    2009-01-01

    Magnetars are young neutron stars with extreme magnetic fields (B > 10^{14}-10^{15}G). How these fields relate to the properties of their progenitor stars is not yet clearly established. However, from the few objects associated with young clusters it has been possible to estimate the initial masses of the progenitors, with results indicating that a very massive progenitor star (M_prog >40Msun) is required to produce a magnetar. Here we present adaptive-optics assisted Keck/NIRC2 imaging and Keck/NIRSPEC spectroscopy of the cluster associated with the magnetar SGR 1900+14, and report that the initial progenitor star mass of the magnetar was a factor of two lower than this limit, M_prog=17 \\pm 2 Msun. Our result presents a strong challenge to the concept that magnetars can only result from very massive progenitors. Instead, we favour a mechanism which is dependent on more than just initial stellar mass for the production of these extreme magnetic fields, such as the "fossil-field" model or a process involving c...

  1. On the Progenitor of the Type IIb Supernova 2016gkg

    CERN Document Server

    Kilpatrick, Charles D; Abramson, Louis E; Pan, Yen-Chen; Lu, Cicero-Xinyu; Williams, Peter; Treu, Tommaso; Siebert, Matthew R; Fassnacht, Christopher D; Max, Claire E

    2016-01-01

    We present a detection in pre-explosion Hubble Space Telescope (HST) imaging of a point source consistent with being the progenitor star of the Type IIb supernova (SN IIb) 2016gkg. Post-explosion imaging from the Keck Adaptive Optics system was used to perform relative astrometry between the Keck and HST imaging. We identify a single point source in the HST images coincident with the SN position to 0.89-sigma. The HST photometry is consistent with the progenitor star being an A0Ia star with T=9500 K and log (L/Lsun)=5.15. We find that the SN 2016gkg progenitor star appears more consistent with binary than single-star evolutionary models. In addition, early-time light curve data from SN 2016gkg revealed a rapid rise in luminosity within ~0.4 days of non-detection limits, consistent with models of the cooling phase after shock break-out. We use these data to determine an explosion date of 20.15 September 2016 and progenitor star radius of log (R/Rsun)=2.41, which agrees with photometry from the progenitor star....

  2. Myostatin promotes the terminal differentiation of embryonic muscle progenitors.

    Science.gov (United States)

    Manceau, Marie; Gros, Jérôme; Savage, Kathleen; Thomé, Virginie; McPherron, Alexandra; Paterson, Bruce; Marcelle, Christophe

    2008-03-01

    Myostatin, a TGF-beta family member, is an important regulator of adult muscle size. While extensively studied in vitro, the mechanisms by which this molecule mediates its effect in vivo are poorly understood. We addressed this question using chick and mouse embryos. We show that while myostatin overexpression in chick leads to an exhaustion of the muscle progenitor population that ultimately results in muscle hypotrophy, myostatin loss of function in chick and mouse provokes an expansion of this population. Our data demonstrate that myostatin acts in vivo to regulate the balance between proliferation and differentiation of embryonic muscle progenitors by promoting their terminal differentiation through the activation of p21 and MyoD. Previous studies have suggested that myostatin imposes quiescence on muscle progenitors. Our data suggest that myostatin's effect on muscle progenitors is more complex than previously realized and is likely to be context-dependent. We propose a novel model for myostatin mode of action in vivo, in which myostatin affects the balance between proliferation and differentiation of embryonic muscle progenitors by enhancing their differentiation.

  3. Corticospinal mirror neurons.

    Science.gov (United States)

    Kraskov, A; Philipp, R; Waldert, S; Vigneswaran, G; Quallo, M M; Lemon, R N

    2014-01-01

    Here, we report the properties of neurons with mirror-like characteristics that were identified as pyramidal tract neurons (PTNs) and recorded in the ventral premotor cortex (area F5) and primary motor cortex (M1) of three macaque monkeys. We analysed the neurons' discharge while the monkeys performed active grasp of either food or an object, and also while they observed an experimenter carrying out a similar range of grasps. A considerable proportion of tested PTNs showed clear mirror-like properties (52% F5 and 58% M1). Some PTNs exhibited 'classical' mirror neuron properties, increasing activity for both execution and observation, while others decreased their discharge during observation ('suppression mirror-neurons'). These experiments not only demonstrate the existence of PTNs as mirror neurons in M1, but also reveal some interesting differences between M1 and F5 mirror PTNs. Although observation-related changes in the discharge of PTNs must reach the spinal cord and will include some direct projections to motoneurons supplying grasping muscles, there was no EMG activity in these muscles during action observation. We suggest that the mirror neuron system is involved in the withholding of unwanted movement during action observation. Mirror neurons are differentially recruited in the behaviour that switches rapidly between making your own movements and observing those of others.

  4. Culturing rat hippocampal neurons.

    Science.gov (United States)

    Audesirk, G; Audesirk, T; Ferguson, C

    2001-01-01

    Cultured neurons are widely used to investigate the mechanisms of neurotoxicity. Embryonic rat hippocampal neurons may be grown as described under a wide variety of conditions to suit differing experimental procedures, including electrophysiology, morphological analysis of neurite development, and various biochemical and molecular analyses.

  5. Role of non-neuronal cells in body weight and appetite control

    Directory of Open Access Journals (Sweden)

    Pilar eArgente-Arizón

    2015-03-01

    Full Text Available The brain is composed of neurons and non-neuronal cells, with the latter encompassing glial, ependymal and endothelial cells, as well as pericytes and progenitor cells. Studies aimed at understanding how the brain operates have traditionally focused on neurons, but the importance of non-neuronal cells has become increasingly evident. Once relegated to supporting roles, it is now indubitable that these diverse cell types are fundamental for brain development and function, including that of metabolic circuits and they may play a significant role in obesity onset and complications. They participate in processes of neurogenesis, synaptogenesis and synaptic plasticity of metabolic circuits both during development and in adulthood. Some glial cells, such as tanycytes and astrocytes, transport circulating nutrients and metabolic factors that are fundamental for neuronal viability and activity into and within the hypothalamus. All of these cell types express receptors for a variety of metabolic factors and hormones, suggesting that they participate in metabolic function. They are the first line of defense against any assault to neurons. Indeed, microglia and astrocytes participate in the hypothalamic inflammatory response to high fat diet (HFD-induced obesity, with this process contributing to inflammatory related insulin and leptin resistance. Moreover, HFD-induced obesity and hyperleptinemia modify hypothalamic astroglial morphology, which is associated with changes in the synaptic inputs to neuronal metabolic circuits. Astrocytic contact with the microvasculature is increased by HFD intake and this could modify nutrient/hormonal uptake into the brain. In addition, progenitor cells in the hypothalamus are now known to have the capacity to renew metabolic circuits and this can be affected by HFD intake and obesity. Here we discuss our current understanding of how non-neuronal cells participate in physiological and physiopathological metabolic control.

  6. Role of Non-Neuronal Cells in Body Weight and Appetite Control

    Science.gov (United States)

    Argente-Arizón, Pilar; Freire-Regatillo, Alejandra; Argente, Jesús; Chowen, Julie A.

    2015-01-01

    The brain is composed of neurons and non-neuronal cells, with the latter encompassing glial, ependymal and endothelial cells, as well as pericytes and progenitor cells. Studies aimed at understanding how the brain operates have traditionally focused on neurons, but the importance of non-neuronal cells has become increasingly evident. Once relegated to supporting roles, it is now indubitable that these diverse cell types are fundamental for brain development and function, including that of metabolic circuits, and they may play a significant role in obesity onset and complications. They participate in processes of neurogenesis, synaptogenesis, and synaptic plasticity of metabolic circuits both during development and in adulthood. Some glial cells, such as tanycytes and astrocytes, transport circulating nutrients and metabolic factors that are fundamental for neuronal viability and activity into and within the hypothalamus. All of these cell types express receptors for a variety of metabolic factors and hormones, suggesting that they participate in metabolic function. They are the first line of defense against any assault to neurons. Indeed, microglia and astrocytes participate in the hypothalamic inflammatory response to high fat diet (HFD)-induced obesity, with this process contributing to inflammatory-related insulin and leptin resistance. Moreover, HFD-induced obesity and hyperleptinemia modify hypothalamic astroglial morphology, which is associated with changes in the synaptic inputs to neuronal metabolic circuits. Astrocytic contact with the microvasculature is increased by HFD intake and this could modify nutrient/hormonal uptake into the brain. In addition, progenitor cells in the hypothalamus are now known to have the capacity to renew metabolic circuits, and this can be affected by HFD intake and obesity. Here, we discuss our current understanding of how non-neuronal cells participate in physiological and physiopathological metabolic control. PMID:25859240

  7. Imaging calcium in neurons.

    Science.gov (United States)

    Grienberger, Christine; Konnerth, Arthur

    2012-03-08

    Calcium ions generate versatile intracellular signals that control key functions in all types of neurons. Imaging calcium in neurons is particularly important because calcium signals exert their highly specific functions in well-defined cellular subcompartments. In this Primer, we briefly review the general mechanisms of neuronal calcium signaling. We then introduce the calcium imaging devices, including confocal and two-photon microscopy as well as miniaturized devices that are used in freely moving animals. We provide an overview of the classical chemical fluorescent calcium indicators and of the protein-based genetically encoded calcium indicators. Using application examples, we introduce new developments in the field, such as calcium imaging in awake, behaving animals and the use of calcium imaging for mapping single spine sensory inputs in cortical neurons in vivo. We conclude by providing an outlook on the prospects of calcium imaging for the analysis of neuronal signaling and plasticity in various animal models.

  8. NEURON and Python

    Directory of Open Access Journals (Sweden)

    Michael Hines

    2009-01-01

    Full Text Available The NEURON simulation program now allows Python to be used, alone or in combination with NEURON's traditional Hoc interpreter. Adding Python to NEURON has the immediate benefit of making available a very extensive suite of analysis tools written for engineering and science. It also catalyzes NEURON software development by offering users a modern programming tool that is recognized for its flexibility and power to create and maintain complex programs. At the same time, nothing is lost because all existing models written in Hoc, including GUI tools, continue to work without change and are also available within the Python context. An example of the benefits of Python availability is the use of the XML module in implementing NEURON's Import3D and CellBuild tools to read MorphML and NeuroML model specifications.

  9. NEURON and Python.

    Science.gov (United States)

    Hines, Michael L; Davison, Andrew P; Muller, Eilif

    2009-01-01

    The NEURON simulation program now allows Python to be used, alone or in combination with NEURON's traditional Hoc interpreter. Adding Python to NEURON has the immediate benefit of making available a very extensive suite of analysis tools written for engineering and science. It also catalyzes NEURON software development by offering users a modern programming tool that is recognized for its flexibility and power to create and maintain complex programs. At the same time, nothing is lost because all existing models written in Hoc, including graphical user interface tools, continue to work without change and are also available within the Python context. An example of the benefits of Python availability is the use of the xml module in implementing NEURON's Import3D and CellBuild tools to read MorphML and NeuroML model specifications.

  10. Development and molecular composition of the hepatic progenitor cell niche.

    Science.gov (United States)

    Vestentoft, Peter Siig

    2013-05-01

    End-stage liver diseases represent major health problems that are currently treated by liver transplantation. However, given the world-wide shortage of donor livers novel strategies are needed for therapeutic treatment. Adult stem cells have the ability to self-renew and differentiate into the more specialized cell types of a given organ and are found in tissues throughout the body. These cells, whose progeny are termed progenitor cells in human liver and oval cells in rodents, have the potential to treat patients through the generation of hepatic parenchymal cells, even from the patient's own tissue. Little is known regarding the nature of the hepatic progenitor cells. Though they are suggested to reside in the most distal part of the biliary tree, the canal of Hering, the lack of unique surface markers for these cells has hindered their isolation and characterization. Upon activation, they proliferate and form ductular structures, termed "ductular reactions", which radiate into the hepatic parenchyma. The ductular reactions contain activated progenitor cells that not only acquire a phenotype resembling that observed in developing liver but also display markers of differentiation shared with the cholangiocytic or hepatocytic lineages, the two parenchymal hepatic cell types. Interactions between the putative progenitor cells, the surrounding support cells and the extracellular matrix scaffold, all constituting the progenitor cell niche, are likely to be important for regulating progenitor cell activity and differentiation. Therefore, identifying novel progenitor cell markers and deciphering their microenvironment could facilitate clinical use. The aims of the present PhD thesis were to expand knowledge of the hepatic progenitor cell niche and characterize it both during development and in disease. Several animal models of hepatic injury are known to induce activation of the progenitor cells. In order to identify possible progenitor cell markers and niche components

  11. Rates and progenitors of type Ia supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Wood-Vasey, William Michael [Univ. of California, Berkeley, CA (United States)

    2004-01-01

    analyzing the true sensitivity of a multi-epoch supernova search and finds a Type Ia supernova rate from z ~ 0.01-0.1 of rV = 4.26$+1.39 +0.10\\atop{-1.93 -0.10}$h3 x 10-4 SNe Ia/yr/Mpc3 from a preliminary analysis of a subsample of the SNfactory prototype search. Several unusual supernovae were found in the course of the SNfactory prototype search. One in particular, SN 2002ic, was the first SN Ia to exhibit convincing evidence for a circumstellar medium and offers valuable insight into the progenitors of Type Ia supernovae.

  12. Gravitational Wave Constraints on the Progenitors of Fast Radio Bursts

    CERN Document Server

    Callister, Thomas; Weinstein, Alan

    2016-01-01

    The nature of fast radio bursts (FRBs) remains enigmatic. Highly energetic radio pulses of millisecond duration, fast radio bursts are observed with dispersion measures consistent with an extragalactic source. A variety of models have been proposed to explain their origin. One popular class of theorized FRB progenitor is the coalescence of compact binaries composed of neutron stars and/or black holes. We demonstrate that measurements made by the LIGO and Virgo gravitational wave observatories can be leveraged to severely constrain the validity of FRB binary coalescence models. Existing measurements rule out binary black holes as FRB progenitors, and results from Advanced LIGO's O1 and O2 observing runs will either confirm or strongly rule out binary neutron star and neutron star-black hole progenitors.

  13. In vitro pancreas organogenesis from dispersed mouse embryonic progenitors

    DEFF Research Database (Denmark)

    Greggio, Chiara; De Franceschi, Filippo; Figueiredo-Larsen, Evan Manuel

    2014-01-01

    The pancreas is an essential organ that regulates glucose homeostasis and secretes digestive enzymes. Research on pancreas embryogenesis has led to the development of protocols to produce pancreatic cells from stem cells (1). The whole embryonic organ can be cultured at multiple stages...... the efficient expansion of dissociated mouse embryonic pancreatic progenitors. By manipulating the composition of the culture medium it is possible to generate either hollow spheres, mainly composed of pancreatic progenitors expanding in their initial state, or, complex organoids which progress to more mature...... expanding progenitors and differentiate into endocrine, acinar and ductal cells and which spontaneously self-organize to resemble the embryonic pancreas. We show here that the in vitro process recapitulates many aspects of natural pancreas development. This culture system is suitable to investigate how...

  14. Suppressive activity of acivicin on murine bone marrow hemopoietic progenitors.

    Science.gov (United States)

    Castello, G; Mencoboni, M; Lerza, R; Cerruti, A; Bogliolo, G; Pannacciulli, I

    1992-01-01

    Acivicin (AVC), a L-glutamine antagonist, is an intriguing antimetabolite coupling cell growth inhibition activity with differentiating effects. In this in vivo study the influence of acivicin on mice bone marrow hemopoietic progenitors was tested. 10 mg/kg b.w./day of acivicin were i.p. injected in B6D2F1 mice for nine days. Leucocyte and reticulocyte level (in peripheral blood), CFU-S (multipotent stem cells) and GM-CFU (granulocyte-macrophage committed progenitors) content in bone marrow were determined during drug administration and for 14 days thereafter. All tested populations decreased severely during the first days of treatment. The drop was particularly striking for bone marrow CFU-S. The recovery of hemopoietic progenitors, however, began while AVC was still administered. These results suggest that the effects of acivicin on normal mouse hemopoietic system are mainly inhibitory, causing considerable myelosuppression.

  15. Flow cytometric data analysis of circulating progenitor cell stability

    Directory of Open Access Journals (Sweden)

    Ernestine A. Mahar

    2017-02-01

    We performed a quality control assessment of the stability of circulating blood progenitor cells in blood samples stored at 4 °C, to determine the time period during which blood samples can be analyzed and yield consistent data for progenitor cell content. Healthy volunteers (n=6 were recruited and underwent phlebotomy, and blood was stored in EDTA tubes at 4 °C. Flow cytometry was performed to quantitate progenitor cell subsets at 0–4 h, 24 h, and 48 h post phlebotomy. All processed samples were fixed with 1% Paraformaldehyde and 1,000,000 total data events were collected. We found no significant differences in PC data for both CD34+ (P=0.68 for one-way ANOVA and CD34+/CD133+ (P=0.74 for one-way ANOVA.

  16. Establishment of bipotent progenitor cell clone from rat skeletal muscle.

    Science.gov (United States)

    Murakami, Yousuke; Yada, Erica; Nakano, Shin-ichi; Miyagoe-Suzuki, Yuko; Hosoyama, Tohru; Matsuwaki, Takashi; Yamanouchi, Keitaro; Nishihara, Masugi

    2011-12-01

    The present study describes the isolation, cloning and characterization of adipogenic progenitor cells from rat skeletal muscle. Among the obtained 10 clones, the most highly adipogenic progenitor, 2G11 cells, were further characterized. In addition to their adipogenicity, 2G11 cells retain myogenic potential as revealed by formation of multinucleated myotubes when co-cultured with myoblasts. 2G11 cells were resistant to an inhibitory effect of basic fibroblast growth factor on adipogenesis, while adipogenesis of widely used preadipogenic cell line, 3T3-L1 cells, was suppressed almost completely by the same treatment. In vivo transplantation experiments revealed that 2G11 cells are able to possess both adipogenicity and myogenicity in vivo. These results indicate the presence of bipotent progenitor cells in rat skeletal muscle, and suggest that such cells may contribute to ectopic fat formation in skeletal muscle.

  17. Close Binary Progenitors and Ejected Companions of Thermonuclear Supernovae

    Science.gov (United States)

    Geier, S.; Kupfer, T.; Heber, U.; Nemeth, P.; Ziegerer, E.; Irrgang, A.; Schindewolf, M.; Marsh, T. R.; Gänsicke, B. T.; Barlow, B. N.; Bloemen, S.

    2017-03-01

    Hot subdwarf stars (sdO/Bs) are evolved core helium-burning stars with very thin hydrogen envelopes, which can be formed by common envelope ejection. Close sdB binaries with massive white dwarf (WD) companions are potential progenitors of thermonuclear supernovae type Ia (SN Ia). We discovered such a progenitor candidate as well as a candidate for a surviving companion star, which escapes from the Galaxy. More candidates for both types of objects have been found by cross-matching known sdB stars with proper motion and light curve catalogues. We found 72 sdO/B candidates with high Galactic restframe velocities, 12 of them might be unbound to our Galaxy. Furthermore, we discovered the second-most compact sdB+WD binary known. However, due to the low mass of the WD companion, it is unlikely to be a SN Ia progenitor.

  18. Omega 3 fatty acids reduce myeloid progenitor cell frequency in the bone marrow of mice and promote progenitor cell differentiation

    Directory of Open Access Journals (Sweden)

    Sollars Vincent E

    2009-03-01

    Full Text Available Abstract Background Omega 3 fatty acids have been found to inhibit proliferation, induce apoptosis, and promote differentiation in various cell types. The processes of cell survival, expansion, and differentiation are of key importance in the regulation of hematopoiesis. We investigated the role of omega 3 fatty acids in controlling the frequency of various myeloid progenitor cells in the bone marrow of mice. Increased progenitor cell frequency and blocked differentiation are characteristics of hematopoietic disorders of the myeloid lineage, such as myeloproliferative diseases and myeloid leukemias. Results We found that increasing the proportion of omega 3 fatty acids relative to the proportion of omega 6 fatty acids in the diet caused increased differentiation and reduced the frequency of myeloid progenitor cells in the bone marrow of mice. Furthermore, this had no adverse effect on peripheral white blood cell counts. Conclusion Our results indicate that omega 3 fatty acids impact hematopoietic differentiation by reducing myeloid progenitor cell frequency in the bone marrow and promoting progenitor cell differentiation. Further exploration of this discovery could lead to the use of omega 3 fatty acids as a therapeutic option for patients that have various disorders of hematopoiesis.

  19. Efficient and cost-effective generation of mature neurons from human induced pluripotent stem cells.

    Science.gov (United States)

    Badja, Cherif; Maleeva, Galyna; El-Yazidi, Claire; Barruet, Emilie; Lasserre, Manon; Tropel, Philippe; Binetruy, Bernard; Bregestovski, Piotr; Magdinier, Frédérique

    2014-12-01

    For years, our ability to study pathological changes in neurological diseases has been hampered by the lack of relevant models until the recent groundbreaking work from Yamanaka's group showing that it is feasible to generate induced pluripotent stem cells (iPSCs) from human somatic cells and to redirect the fate of these iPSCs into differentiated cells. In particular, much interest has focused on the ability to differentiate human iPSCs into neuronal progenitors and functional neurons for relevance to a large number of pathologies including mental retardation and behavioral or degenerative syndromes. Current differentiation protocols are time-consuming and generate limited amounts of cells, hindering use on a large scale. We describe a feeder-free method relying on the use of a chemically defined medium that overcomes the need for embryoid body formation and neuronal rosette isolation for neuronal precursors and terminally differentiated neuron production. Four days after induction, expression of markers of the neurectoderm lineage is detectable. Between 4 and 7 days, neuronal precursors can be expanded, frozen, and thawed without loss of proliferation and differentiation capacities or further differentiated. Terminal differentiation into the different subtypes of mature neurons found in the human brain were observed. At 6-35 days after induction, cells express typical voltage-gated and ionotrophic receptors for GABA, glycine, and acetylcholine. This specific and efficient single-step strategy in a chemically defined medium allows the production of mature neurons in 20-40 days with multiple applications, especially for modeling human pathologies.

  20. Modeling distinct osteosarcoma subtypes in vivo using Cre:lox and lineage-restricted transgenic shRNA.

    Science.gov (United States)

    Mutsaers, Anthony J; Ng, Alvin J M; Baker, Emma K; Russell, Megan R; Chalk, Alistair M; Wall, Meaghan; Liddicoat, Brain J J; Ho, Patricia W M; Slavin, John L; Goradia, Ankita; Martin, T John; Purton, Louise E; Dickins, Ross A; Walkley, Carl R

    2013-07-01

    Osteosarcoma is the most common primary cancer of bone and one that predominantly affects children and adolescents. Osteoblastic osteosarcoma represents the major subtype of this tumor, with approximately equal representation of fibroblastic and chondroblastic subtypes. We and others have previously described murine models of osteosarcoma based on osteoblast-restricted Cre:lox deletion of Trp53 (p53) and Rb1 (Rb), resulting in a phenotype most similar to fibroblastic osteosarcoma in humans. We now report a model of the most prevalent form of human osteosarcoma, the osteoblastic subtype. In contrast to other osteosarcoma models that have used Cre:lox mediated gene deletion, this model was generated through shRNA-based knockdown of p53. As is the case with the human disease the shRNA tumors most frequently present in the long bones and preferentially disseminate to the lungs; feature less consistently modeled using Cre:lox approaches. Our approach allowed direct comparison of the in vivo consequences of targeting the same genetic drivers using two different technologies, Cre:lox and shRNA. This demonstrated that the effects of Cre:lox and shRNA mediated knock-down are qualitatively different, at least in the context of osteosarcoma, and yielded distinct subtypes of osteosarcoma. Through the use of complementary genetic modification strategies we have established a model of the most common clinical subtype of osteosarcoma that was not previously represented and more fully recapitulated the clinical spectrum of this cancer. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Hematopoietic stem cell and progenitor cell mechanisms in myelodysplastic syndromes

    Science.gov (United States)

    Pang, Wendy W.; Pluvinage, John V.; Price, Elizabeth A.; Sridhar, Kunju; Arber, Daniel A.; Greenberg, Peter L.; Schrier, Stanley L.; Park, Christopher Y.; Weissman, Irving L.

    2013-01-01

    Myelodysplastic syndromes (MDS) are a group of disorders characterized by variable cytopenias and ineffective hematopoiesis. Hematopoietic stem cells (HSCs) and myeloid progenitors in MDS have not been extensively characterized. We transplanted purified human HSCs from MDS samples into immunodeficient mic