WorldWideScience

Sample records for oligodendrocyte precursor cells

  1. Doublecortin in Oligodendrocyte Precursor Cells in the Adult Mouse Brain

    Science.gov (United States)

    Boulanger, Jenna J.; Messier, Claude

    2017-01-01

    Key Points Oligodendrocyte precursor cells express doublecortin, a microtubule-associated protein.Oligodendrocyte precursor cells express doublecortin, but at a lower level of expression than in neuronal precursor.Doublecortin is not associated with a potential immature neuronal phenotype in Oligodendrocyte precursor cells. Oligodendrocyte precursor cells (OPC) are glial cells that differentiate into myelinating oligodendrocytes during embryogenesis and early stages of post-natal life. OPCs continue to divide throughout adulthood and some eventually differentiate into oligodendrocytes in response to demyelinating lesions. There is growing evidence that OPCs are also involved in activity-driven de novo myelination of previously unmyelinated axons and myelin remodeling in adulthood. Considering these roles in the adult brain, OPCs are likely mobile cells that can migrate on some distances before they differentiate into myelinating oligodendrocytes. A number of studies have noted that OPCs express doublecortin (DCX), a microtubule-associated protein expressed in neural precursor cells and in migrating immature neurons. Here we describe the distribution of DCX in OPCs. We found that almost all OPCs express DCX, but the level of expression appears to be much lower than what is found in neural precursor. We found that DCX is downregulated when OPCs start expressing mature oligodendrocyte markers and is absent in myelinating oligodendrocytes. DCX does not appear to signal an immature neuronal phenotype in OPCs in the adult mouse brain. Rather, it could be involved either in cell migration, or as a marker of an immature oligodendroglial cell phenotype.

  2. 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

  3. Diazoxide promotes oligodendrocyte precursor cell proliferation and myelination.

    Directory of Open Access Journals (Sweden)

    Birgit Fogal

    Full Text Available BACKGROUND: Several clinical conditions are associated with white matter injury, including periventricular white matter injury (PWMI, which is a form of brain injury sustained by preterm infants. It has been suggested that white matter injury in this condition is due to altered oligodendrocyte (OL development or death, resulting in OL loss and hypomyelination. At present drugs are not available that stimulate OL proliferation and promote myelination. Evidence suggests that depolarizing stimuli reduces OL proliferation and differentiation, whereas agents that hyperpolarize OLs stimulate OL proliferation and differentiation. Considering that the drug diazoxide activates K(ATP channels to hyperpolarize cells, we tested if this compound could influence OL proliferation and myelination. METHODOLOGY/FINDINGS: Studies were performed using rat oligodendrocyte precursor cell (OPC cultures, cerebellar slice cultures, and an in vivo model of PWMI in which newborn mice were exposed to chronic sublethal hypoxia (10% O(2. We found that K(ATP channel components Kir 6.1 and 6.2 and SUR2 were expressed in oligodendrocytes. Additionally, diazoxide potently stimulated OPC proliferation, as did other K(ATP activators. Diazoxide also stimulated myelination in cerebellar slice cultures. We also found that diazoxide prevented hypomyelination and ventriculomegaly following chronic sublethal hypoxia. CONCLUSIONS: These results identify KATP channel components in OLs and show that diazoxide can stimulate OL proliferation in vitro. Importantly we find that diazoxide can promote myelination in vivo and prevent hypoxia-induced PWMI.

  4. Adrenomedullin promotes differentiation of oligodendrocyte precursor cells into myelin-basic-protein expressing oligodendrocytes under pathological conditions in vitro.

    Science.gov (United States)

    Maki, Takakuni; Takahashi, Yoko; Miyamoto, Nobukazu; Liang, Anna C; Ihara, Masafumi; Lo, Eng H; Arai, Ken

    2015-07-01

    Oligodendrocytes, which are the main cell type in cerebral white matter, are generated from their precursor cells (oligodendrocyte precursor cells: OPCs). However, the differentiation from OPCs to oligodendrocytes is disturbed under stressed conditions. Therefore, drugs that can improve oligodendrocyte regeneration may be effective for white matter-related diseases. Here we show that a vasoactive peptide adrenomedullin (AM) promotes the in vitro differentiation of OPCs under pathological conditions. Primary OPCs were prepared from neonatal rat brains, and differentiated into myelin-basic-protein expressing oligodendrocytes over time. This in vitro OPC differentiation was inhibited by prolonged chemical hypoxic stress induced by non-lethal CoCl(2) treatment. However, AM promoted the OPC differentiation under the hypoxic stress conditions, and the AM receptor antagonist AM(22-52) canceled the AM-induced OPC differentiation. In addition, AM treatment increased the phosphorylation level of Akt in OPC cultures, and correspondingly, the PI3K/Akt inhibitor LY294002 blocked the AM-induced OPC differentiation. Taken together, AM treatment rescued OPC maturation under pathological conditions via an AM-receptor-PI3K/Akt pathway. Oligodendrocytes play critical roles in white matter by forming myelin sheath. Therefore, AM signaling may be a promising therapeutic target to boost oligodendrocyte regeneration in CNS disorders.

  5. Auraptene induces oligodendrocyte lineage precursor cells in a cuprizone-induced animal model of demyelination.

    Science.gov (United States)

    Nakajima, Mitsunari; Shimizu, Risei; Furuta, Kohei; Sugino, Mami; Watanabe, Takashi; Aoki, Rui; Okuyama, Satoshi; Furukawa, Yoshiko

    2016-05-15

    We investigated the effects of auraptene on mouse oligodendroglial cell lineage in an animal model of demyelination induced by cuprizone. Auraptene, a citrus coumarin, was intraperitoneally administered to mice fed the demyelinating agent cuprizone. Immunohistochemical analysis of the corpus callosum and/or Western blotting analysis of brain extracts revealed that cuprizone reduced immunoreactivity for myelin-basic protein, a marker of myelin, whereas it increased immunoreactivity to platelet derived-growth factor receptor-α, a marker of oligodendrocyte precursor cells. Administration of auraptene enhanced the immunoreactivity to oligodendrocyte transcription factor 2, a marker of oligodendrocyte precursor cells and oligodendrocyte lineage precursor cells, but had no effect on immunoreactivity to myelin-basic protein or platelet-derived growth factor receptor-α. These findings suggest that auraptene promotes the production of oligodendrocyte lineage precursor cells in an animal model of demyelination and may be useful for individuals with demyelinating diseases. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Differentiation of rat oligodendrocyte precursor cells in chemical conditional medium in vitro

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Objective: To investigate in vitro differentiation of oligodendrocyte precursor cells (OPCs) into mature oligodendrocytes in chemical conditional medium. Methods: The mixed glial cells from cerebral cortices of 48-hour-old Sprague-Dawley (SD) rats were cultured in vitro. The OPCs were separated by shaking procedure around 9-10 d in the primary culture. Then the isolated OPCs were further transferred into the chemical conditional medium for cell differentiation. The pattern of OPCs maturation in vitro was continuously observed with contrast phase microscopy and mature oligodendrocytes were further identified by immunocytochemical assays. Results: OPCs grew well when co-cultured with glial cells and distinct cellular stratification formed about 9-10 d in the primary culture, which indicated the appropriate opportunity for the separation of OPCs. Following cultured in the chemical conditional medium, the OPCs progressively differentiated into the mature oligodendrocytes. These mature oligodendrocytes were also immunostained with the oligodendrocyte lineage-specific antibody, Oligo2. Conclusion: The OPCs isolated from the cerebral cortices of neonatal SD rats can progressively differentiate into mature oligodendrocytes in the chemical conditional medium in vitro.

  7. In vitro transdifferentiation of human cultured CD34+ stem cells into oligodendrocyte precursors using thyroid hormones.

    Science.gov (United States)

    Venkatesh, Katari; Srikanth, Lokanathan; Vengamma, Bhuma; Chandrasekhar, Chodimella; Prasad, Bodapati Chandra Mouleshwara; Sarma, Potukuchi Venkata Gurunadha Krishna

    2015-02-19

    The extent of myelination on the axon promotes transmission of impulses in the neural network, any disturbances in this process results in the neurodegenerative condition. Transplantation of oligodendrocyte precursors that supports in the regeneration of axons through myelination is an important step in the restoration of damaged neurons. Therefore, in the present study, the differentiation of human CD34+ stem cells into oligodendrocytes was carried out. The pure human CD34+ culture developed from the stem cells obtained from a peripheral blood of a donor were subjected to oligodendrocyte differentiation medium (ODM). The ODM at a concentration of 40ng/ml thyroxine, 40ng/ml 3,3',5-tri-iodo-thyronine showed distinct morphological changes from day 6 to 9 with cells exhibiting conspicuous stellate morphology and extensive foot processes. The real-time PCR analysis showed prominent expression of Olig2, CNPase, PDGFRα and PLP1/DM20 in the differentiated cells confirming the formed cells are oligodendrocyte precursors. The expression of these genes increased from days 6 to 9 corresponding to the morphological changes observed with almost no expression of GFAP+ cells. The distinct CNPase activity was observed in these differentiated cells compared to normal CD34+ stem cells correlating with results of real-time PCR conclusively explains the development of oligodendrocytes from human CD34+ stem cells.

  8. Slit2 regulates the dispersal of oligodendrocyte precursor cells via Fyn/RhoA signaling.

    Science.gov (United States)

    Liu, Xiujie; Lu, Yan; Zhang, Yong; Li, Yuanyuan; Zhou, Jiazhen; Yuan, Yimin; Gao, Xiaofei; Su, Zhida; He, Cheng

    2012-05-18

    Oligodendrocyte precursor cells (OPCs) are a unique type of glia that are responsible for the myelination of the central nervous system. OPC migration is important for myelin formation during central nervous system development and repair. However, the precise extracellular and intracellular mechanisms that regulate OPC migration remain elusive. Slits were reported to regulate neurodevelopmental processes such as migration, adhesion, axon guidance, and elongation through binding to roundabout receptors (Robos). However, the potential roles of Slits/Robos in oligodendrocytes remain unknown. In this study, Slit2 was found to be involved in regulating the dispersal of OPCs through the association between Robo1 and Fyn. Initially, we examined the expression of Robos in OPCs both in vitro and in vivo. Subsequently, the Boyden chamber assay showed that Slit2 could inhibit OPC migration. RoboN, a specific inhibitor of Robos, could significantly attenuate this effect. The effects were confirmed through the explant migration assay. Furthermore, treating OPCs with Slit2 protein deactivated Fyn and increased the level of activated RhoA-GTP. Finally, Fyn was found to form complexes with Robo1, but this association was decreased after Slit2 stimulation. Thus, we demonstrate for the first time that Slit2 regulates the dispersal of oligodendrocyte precursor cells through Fyn and RhoA signaling.

  9. Transplanted microvascular endothelial cells promote oligodendrocyte precursor cell survival in ischemic demyelinating lesions.

    Science.gov (United States)

    Iijima, Keiya; Kurachi, Masashi; Shibasaki, Koji; Naruse, Masae; Puentes, Sandra; Imai, Hideaki; Yoshimoto, Yuhei; Mikuni, Masahiko; Ishizaki, Yasuki

    2015-11-01

    We previously showed that transplantation of brain microvascular endothelial cells (MVECs) greatly stimulated remyelination in the white matter infarct of the internal capsule (IC) induced by endothelin-1 injection and improved the behavioral outcome. In the present study, we examined the effect of MVEC transplantation on the infarct volume using intermittent magnetic resonance image and on the behavior of oligodendrocyte lineage cells histochemically. Our results in vivo show that MVEC transplantation reduced the infarct volume in IC and apoptotic death of oligodendrocyte precursor cells (OPCs). These results indicate that MVECs have a survival effect on OPCs, and this effect might contribute to the recovery of the white matter infarct. The conditioned-medium from cultured MVECs reduced apoptosis of cultured OPCs, while the conditioned medium from cultured fibroblasts did not show such effect. These results suggest a possibility that transplanted MVECs increased the number of OPCs through the release of humoral factors that prevent their apoptotic death. Identification of such humoral factors may lead to the new therapeutic strategy against ischemic demyelinating diseases.

  10. Hypoxia alters cell cycle regulatory protein expression and induces premature maturation of oligodendrocyte precursor cells.

    Directory of Open Access Journals (Sweden)

    Ravi Shankar Akundi

    Full Text Available BACKGROUND: Periventricular white matter injury (PWMI is a common form of brain injury sustained by preterm infants. A major factor that predisposes to PWMI is hypoxia. Because oligodendrocytes (OLs are responsible for myelination of axons, abnormal OL development or function may affect brain myelination. At present our understanding of the influences of hypoxia on OL development is limited. To examine isolated effects of hypoxia on OLs, we examined the influences of hypoxia on OL development in vitro. METHODOLOGY/FINDINGS: Cultures of oligodendrocyte precursor cells (OPCs were prepared from mixed glial cultures and were 99% pure. OPCs were maintained at 21% O(2 or hypoxia (1% or 4% O(2 for up to 7 days. We observed that 1% O(2 lead to an increase in the proportion of myelin basic protein (MBP-positive OLs after 1 week in culture, and a decrease in the proportion of platelet-derived growth factor receptor alpha (PDGFRalpha-positive cells suggesting premature OL maturation. Increased expression of the cell cycle regulatory proteins p27(Kip1 and phospho-cdc2, which play a role in OL differentiation, was seen as well. CONCLUSIONS: These results show that hypoxia interferes with the normal process of OL differentiation by inducing premature OPC maturation.

  11. Differential proliferation rhythm of neural progenitor and oligodendrocyte precursor cells in the young adult hippocampus.

    Directory of Open Access Journals (Sweden)

    Yoko Matsumoto

    Full Text Available Oligodendrocyte precursor cells (OPCs are a unique type of glial cells that function as oligodendrocyte progenitors while constantly proliferating in the normal condition from rodents to humans. However, the functional roles they play in the adult brain are largely unknown. In this study, we focus on the manner of OPC proliferation in the hippocampus of the young adult mice. Here we report that there are oscillatory dynamics in OPC proliferation that differ from neurogenesis in the subgranular zone (SGZ; the former showed S-phase and M-phase peaks in the resting and active periods, respectively, while the latter only exhibited M-phase peak in the active period. There is coincidence between different modes of proliferation and expression of cyclin proteins that are crucial for cell cycle; cyclin D1 is expressed in OPCs, while cyclin D2 is observed in neural stem cells. Similar to neurogenesis, the proliferation of hippocampal OPCs was enhanced by voluntary exercise that leads to an increase in neuronal activity in the hippocampus. These data suggest an intriguing control of OPC proliferation in the hippocampus.

  12. Transplantation of oligodendrocyte precursor cells improves locomotion deficits in rats with spinal cord irradiation injury.

    Directory of Open Access Journals (Sweden)

    Yan Sun

    Full Text Available Demyelination contributes to the functional impairment of irradiation injured spinal cord. One potential therapeutic strategy involves replacing the myelin-forming cells. Here, we asked whether transplantation of Olig2(+-GFP(+-oligodendrocyte precursor cells (OPCs, which are derived from Olig2-GFP-mouse embryonic stem cells (mESCs, could enhance remyelination and functional recovery after spinal cord irradiation injury. We differentiated Olig2-GFP-mESCs into purified Olig2(+-GFP(+-OPCs and transplanted them into the rats' cervical 4-5 dorsal spinal cord level at 4 months after irradiation injury. Eight weeks after transplantation, the Olig2(+-GFP(+-OPCs survived and integrated into the injured spinal cord. Immunofluorescence analysis showed that the grafted Olig2(+-GFP(+-OPCs primarily differentiated into adenomatous polyposis coli (APC(+ oligodendrocytes (54.6±10.5%. The staining with luxol fast blue, hematoxylin & eosin (LFB/H&E and electron microscopy demonstrated that the engrafted Olig2(+-GFP(+-OPCs attenuated the demyelination resulted from the irradiation. More importantly, the recovery of forelimb locomotor function was enhanced in animals receiving grafts of Olig2(+-GFP(+-OPCs. We concluded that OPC transplantation is a feasible therapy to repair the irradiated lesions in the central nervous system (CNS.

  13. Human umbilical cord Wharton's jelly-derived oligodendrocyte precursor-like cells for axon and myelin sheath regeneration

    Institute of Scientific and Technical Information of China (English)

    Hong Chen; Yan Zhang; Zhijun Yang; Hongtian Zhang

    2013-01-01

    Human umbilical mesenchymal stem cells from Wharton's jelly of the umbilical cord were induced to differentiate into oligodendrocyte precursor-like cells in vitro. Oligodendrocyte precursor cells were transplanted into contused rat spinal cords. Immunofluorescence double staining indicated that transplanted cells survived in injured spinal cord, and differentiated into mature and immature oligodendrocyte precursor cells. Biotinylated dextran amine tracing results showed that cell transplantation promoted a higher density of the corticospinal tract in the central and caudal parts of the injured spinal cord. Luxol fast blue and toluidine blue staining showed that the volume of residual myelin was significantly increased at 1 and 2 mm rostral and caudal to the lesion epicenter after cell transplantation. Furthermore, immunofluorescence staining verified that the newly regenerated myelin sheath was derived from the central nervous system. Basso, Beattie and Bresnahan testing showed an evident behavioral recovery. These results suggest that human umbilical mesenchymal stem cell-derived oligodendrocyte precursor cells promote the regeneration of spinal axons and myelin sheaths.

  14. Role of the cellular prion protein in oligodendrocyte precursor cell proliferation and differentiation in the developing and adult mouse CNS.

    Directory of Open Access Journals (Sweden)

    Ana Bribián

    Full Text Available There are numerous studies describing the signaling mechanisms that mediate oligodendrocyte precursor cell (OPC proliferation and differentiation, although the contribution of the cellular prion protein (PrP(c to this process remains unclear. PrP(c is a glycosyl-phosphatidylinositol (GPI-anchored glycoprotein involved in diverse cellular processes during the development and maturation of the mammalian central nervous system (CNS. Here we describe how PrP(c influences oligodendrocyte proliferation in the developing and adult CNS. OPCs that lack PrP(c proliferate more vigorously at the expense of a delay in differentiation, which correlates with changes in the expression of oligodendrocyte lineage markers. In addition, numerous NG2-positive cells were observed in cortical regions of adult PrP(c knockout mice, although no significant changes in myelination can be seen, probably due to the death of surplus cells.

  15. Anosmin-1 over-expression regulates oligodendrocyte precursor cell proliferation, migration and myelin sheath thickness.

    Science.gov (United States)

    Murcia-Belmonte, Verónica; Esteban, Pedro F; Martínez-Hernández, José; Gruart, Agnès; Luján, Rafael; Delgado-García, José María; de Castro, Fernando

    2016-04-01

    During development of the central nervous system, anosmin-1 (A1) works as a chemotropic cue contributing to axonal outgrowth and collateralization, as well as modulating the migration of different cell types, fibroblast growth factor receptor 1 (FGFR1) being the main receptor involved in all these events. To further understand the role of A1 during development, we have analysed the over-expression of human A1 in a transgenic mouse line. Compared with control mice during development and in early adulthood, A1 over-expressing transgenic mice showed an enhanced oligodendrocyte precursor cell (OPC) proliferation and a higher number of OPCs in the subventricular zone and in the corpus callosum (CC). The migratory capacity of OPCs from the transgenic mice is increased in vitro due to a higher basal activation of ERK1/2 mediated through FGFR1 and they also produced more myelin basic protein (MBP). In vivo, the over-expression of A1 resulted in an elevated number of mature oligodendrocytes with higher levels of MBP mRNA and protein, as well as increased levels of activation of the ERK1/2 proteins, while electron microscopy revealed thicker myelin sheaths around the axons of the CC in adulthood. Also in the mature CC, the nodes of Ranvier were significantly longer and the conduction velocity of the nerve impulse in vivo was significantly increased in the CC of A1 over-expressing transgenic mice. Altogether, these data confirmed the involvement of A1 in oligodendrogliogenesis and its relevance for myelination.

  16. Transformation of quiescent adult oligodendrocyte precursor cells into malignant glioma through a multistep reactivation process.

    Science.gov (United States)

    Galvao, Rui Pedro; Kasina, Anita; McNeill, Robert S; Harbin, Jordan E; Foreman, Oded; Verhaak, Roel G W; Nishiyama, Akiko; Miller, C Ryan; Zong, Hui

    2014-10-07

    How malignant gliomas arise in a mature brain remains a mystery, hindering the development of preventive and therapeutic interventions. We previously showed that oligodendrocyte precursor cells (OPCs) can be transformed into glioma when mutations are introduced perinatally. However, adult OPCs rarely proliferate compared with their perinatal counterparts. Whether these relatively quiescent cells have the potential to transform is unknown, which is a critical question considering the late onset of human glioma. Additionally, the premalignant events taking place between initial mutation and a fully developed tumor mass are particularly poorly understood in glioma. Here we used a temporally controllable Cre transgene to delete p53 and NF1 specifically in adult OPCs and demonstrated that these cells consistently give rise to malignant gliomas. To investigate the transforming process of quiescent adult OPCs, we then tracked these cells throughout the premalignant phase, which revealed a dynamic multistep transformation, starting with rapid but transient hyperproliferative reactivation, followed by a long period of dormancy, and then final malignant transformation. Using pharmacological approaches, we discovered that mammalian target of rapamycin signaling is critical for both the initial OPC reactivation step and late-stage tumor cell proliferation and thus might be a potential target for both glioma prevention and treatment. In summary, our results firmly establish the transforming potential of adult OPCs and reveal an actionable multiphasic reactivation process that turns slowly dividing OPCs into malignant gliomas.

  17. 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.

  18. WIN55,212-2 protects oligodendrocyte precursor cells in stroke penumbra following permanent focal cerebral ischemia in rats

    OpenAIRE

    SUN, JING; Fang, Yin-quan; Ren, Hong; Tao CHEN; Guo, Jing-Jing; Yan, Jun; SONG, SHU; Zhang, Lu-yong; Liao, Hong

    2012-01-01

    Aim: To explore whether the synthetic cannabinoid receptor agonist WIN55,212-2 could protect oligodendrocyte precursor cells (OPCs) in stroke penumbra, thereby providing neuroprotection following permanent focal cerebral ischemia in rats. Methods: Adult male SD rats were subjected to permanent middle cerebral artery occlusion (p-MCAO). The animals were administered WIN55,212-2 at 2 h, and sacrificed at 24 h after the ischemic insult. The infarct volumes and brain swelling were assessed. The e...

  19. A complex between contactin-1 and the protein tyrosine phosphatase PTPRZ controls the development of oligodendrocyte precursor cells

    Energy Technology Data Exchange (ETDEWEB)

    Lamprianou, Smaragda; Chatzopoulou, Elli; Thomas, Jean-Léon; Bouyain, Samuel; Harroch, Sheila (IP-Korea); (UPMC); (UMKC)

    2013-09-23

    The six members of the contactin (CNTN) family of neural cell adhesion molecules are involved in the formation and maintenance of the central nervous system (CNS) and have been linked to mental retardation and neuropsychiatric disorders such as autism. Five of the six CNTNs bind to the homologous receptor protein tyrosine phosphatases gamma (PTPRG) and zeta (PTPRZ), but the biological roles of these interactions remain unclear. We report here the cocrystal structure of the carbonic anhydrase-like domain of PTPRZ bound to tandem Ig repeats of CNTN1 and combine these structural data with binding assays to show that PTPRZ binds specifically to CNTN1 expressed at the surface of oligodendrocyte precursor cells. Furthermore, analyses of glial cell populations in wild-type and PTPRZ-deficient mice show that the binding of PTPRZ to CNTN1 expressed at the surface of oligodendrocyte precursor cells inhibits their proliferation and promotes their development into mature oligodendrocytes. Overall, these results implicate the PTPRZ/CNTN1 complex as a previously unknown modulator of oligodendrogenesis.

  20. Adjunctive MSCs enhance myelin formation by xenogenic oligodendrocyte precursors transplanted in the retina

    Institute of Scientific and Technical Information of China (English)

    Aileen Arriola; Mary E Kie; Yufang Shi; Randall D McKinnon

    2010-01-01

    Dear Editor, We examined myelin formation by oligodendrocytes co-transplanted with immunosuppressive mesenchymal stem cells (MSCs). Oligodendrocyte precursor cells (OPCs) were grafted into the mouse retina, and graft survival and maturation was determined with or without adjunctive MSCs.

  1. CNTF promotes the survival and differentiation of adult spinal cord-derived oligodendrocyte precursor cells in vitro but fails to promote remyelination in vivo.

    Science.gov (United States)

    Talbott, Jason F; Cao, Qilin; Bertram, James; Nkansah, Michael; Benton, Richard L; Lavik, Erin; Whittemore, Scott R

    2007-03-01

    Delivery of factors capable of promoting oligodendrocyte precursor cell (OPC) survival and differentiation in vivo is an important therapeutic strategy for a variety of pathologies in which demyelination is a component, including multiple sclerosis and spinal cord injury. Ciliary neurotrophic factor (CNTF) is a neuropoietic cytokine that promotes both survival and maturation of a variety of neuronal and glial cell populations, including oligodendrocytes. Present results suggest that, although CNTF has a potent survival and differentiation promoting effect in vitro on OPCs isolated from the adult spinal cord, CNTF administration in vivo is not sufficient to promote oligodendrocyte remyelination in the glial-depleted environment of unilateral ethidium bromide (EB) lesions.

  2. Polysialic acid modification of the synaptic cell adhesion molecule SynCAM 1 in human embryonic stem cell-derived oligodendrocyte precursor cells

    Directory of Open Access Journals (Sweden)

    Sebastian Werneburg

    2015-05-01

    Full Text Available Oligodendrocyte precursor cells (OPCs are the progenitors of myelinating oligodendrocytes in brain development and repair. Successful myelination depends on the control of adhesiveness during OPC migration and axon contact formation. The decoration of cell surface proteins with the glycan polysialic acid (polySia is a key regulatory element of OPC interactions during development and under pathological conditions. By far the major protein carrier of polySia is the neural cell adhesion molecule NCAM, but recently, polysialylation of the synaptic cell adhesion molecule SynCAM 1 has been detected in the developing mouse brain. In mice, polySia-SynCAM 1 is associated with cells expressing NG2, a marker of a heterogeneous precursor cell population, which is the primary source for oligodendrocytes in development and myelin repair but can also give rise to astrocytes and possibly neurons. It is not yet clear if polySia-SynCAM 1 is expressed by OPCs and its occurrence in humans is elusive. By generating uniform human embryonic stem cell-derived OPC cultures, we demonstrate that polySia is present on human OPCs but down-regulated during differentiation into myelin basic protein-positive oligodendrocytes. PolySia on NCAM resides on the isoforms NCAM-180 and NCAM-140, and SynCAM 1 is identified as a novel polySia acceptor in human OPCs.

  3. Quiescence of adult oligodendrocyte precursor cells requires thyroid hormone and hypoxia to activate Runx1.

    Science.gov (United States)

    Tokumoto, Yasuhito; Tamaki, Shinpei; Kabe, Yasuaki; Takubo, Keiyo; Suematsu, Makoto

    2017-04-21

    The adult mammalian central nervous system (CNS) contains a population of slowly dividing oligodendrocyte precursor cells (OPCs), i.e., adult OPCs, which supply new oligodendrocytes throughout the life of animal. While adult OPCs develop from rapidly dividing perinatal OPCs, the mechanisms underlying their quiescence remain unknown. Here, we show that perinatal rodent OPCs cultured with thyroid hormone (TH) under hypoxia become quiescent and acquire adult OPCs-like characteristics. The cyclin-dependent kinase inhibitor p15/INK4b plays crucial roles in the TH-dependent cell cycle deceleration in OPCs under hypoxia. Klf9 is a direct target of TH-dependent signaling. Under hypoxic conditions, hypoxia-inducible factors mediates runt-related transcription factor 1 activity to induce G1 arrest in OPCs through enhancing TH-dependent p15/INK4b expression. As adult OPCs display phenotypes of adult somatic stem cells in the CNS, the current results shed light on environmental requirements for the quiescence of adult somatic stem cells during their development from actively proliferating stem/progenitor cells.

  4. The effect of glia-glia interactions on oligodendrocyte precursor cell biology during development and in demyelinating diseases

    Directory of Open Access Journals (Sweden)

    Diego eClemente

    2013-12-01

    Full Text Available Oligodendrocyte precursor cells (OPCs originate in specific areas of the developing central nervous system (CNS. Once generated, they migrate towards their destinations where they differentiate into mature oligodendrocytes. In the adult, 5-8% of all cells in the CNS are OPCs, cells that retain the capacity to proliferate, migrate and differentiate into oligodendrocytes. Indeed, these endogenous OPCs react to damage in demyelinating diseases, like multiple sclerosis (MS, representing a key element in spontaneous remyelination. In the present work, we review the specific interactions between OPCs and other glial cells (astrocytes, microglia during CNS development and in the pathological scenario of MS. We focus on: i the role of astrocytes in maintaining the homeostasis and spatial distribution of different secreted cues that determine OPC proliferation, migration and differentiation during CNS development; ii the role of microglia and astrocytes in the redistribution of iron, which is crucial for myelin synthesis during CNS development and for myelin repair in MS; iii how microglia secrete different molecules, e.g. growth factors, that favor the recruitment of OPCs in acute phases of MS lesions; and iv how astrocytes modify the extracellular matrix in MS lesions, affecting the ability of OPCs to attempt spontaneous remyelination. Together, these issues demonstrate how both astroglia and microglia influence OPCs in physiological and pathological situations, reinforcing the concept that both development and neural repair are complex and global phenomena. Understanding the molecular and cellular mechanisms that control OPC survival, proliferation, migration and differentiation during development, as well as in the mature CNS, may open new opportunities in the search for reparative therapies in demyelinating diseases like MS.

  5. Protocol to isolate a large amount of functional oligodendrocyte precursor cells from the cerebral cortex of adult mice and humans.

    Directory of Open Access Journals (Sweden)

    Eva María Medina-Rodríguez

    Full Text Available During development, oligodendrocytes are generated from oligodendrocyte precursor cells (OPCs, a cell type that is a significant proportion of the total cells (3-8% in the adult central nervous system (CNS of both rodents and humans. Adult OPCs are responsible for the spontaneous remyelination that occurs in demyelinating diseases like Multiple Sclerosis (MS and they constitute an interesting source of cells for regenerative therapy in such conditions. However, there is little data regarding the neurobiology of adult OPCs isolated from mice since an efficient method to isolate them has yet to be established. We have designed a protocol to obtain viable adult OPCs from the cerebral cortex of different mouse strains and we have compared its efficiency with other well-known methods. In addition, we show that this protocol is also useful to isolate functional OPCs from human brain biopsies. Using this method we can isolate primary cortical OPCs in sufficient quantities so as to be able to study their survival, maturation and function, and to facilitate an evaluation of their utility in myelin repair.

  6. An in vitro study on the involvement of LINGO-1 and Rho GTPases in Nogo-A regulated differentiation of oligodendrocyte precursor cells.

    Science.gov (United States)

    Zhao, Xiang-Hui; Jin, Wei-Lin; Ju, Gong

    2007-10-01

    Nogo-A has been considered as one of the most important myelin-associated axonal regeneration inhibitors in the central nervous system. Recent studies have demonstrated various additional physiological roles of Nogo family members. To understand the possible effect of Nogo-A on the differentiation of oligodendrocytes, antibodies against distinct extracellular domains of Nogo-A were applied in cell cultures. Oligodendrocyte precursor cells from P2 rat cortex were grown in the presence of monoclonal antibody against the N-terminal inhibitory domain of Nogo-A or the C-terminal 66 amino acid loop of Nogo-A for 3 days, and the antibody treatment resulted in stunted process extension and inhibited differentiation of oligodendrocytes. Concomitant with morphology changes, Rho GTPases activity was greatly increased upon the antibody treatment and the expression level of LINGO-1, which was recently shown to be a negative regulator for the oligodendrocyte maturation, was upregulated in the process of antibody treatment. These results indicate that endogenous Nogo-A expressed in oligodendrocyte may act though Rho GTPase and LINGO-1 to influence the morphological differentiation of oligodendrocytes and will help us to understand the physiology role of Nogo-A in oligodendrocyte biology.

  7. Improved differentiation of oligodendrocyte precursor cells and neurological function after spinal cord injury in rats by oscillating field stimulation.

    Science.gov (United States)

    Jing, J-H; Qian, J; Zhu, N; Chou, W-B; Huang, X-J

    2015-09-10

    Oscillating field stimulation (OFS) has been used in attempts to treat spinal cord injury (SCI) and has been shown to improve remyelination after SCI in rats. However, some controversies regarding the effects of OFS have been presented in previous papers. Oligodendrocytes (OLs) are the main cell for remyelination and are derived from the differentiation of oligodendrocyte precursor cells (OPCs). To date, it has been unclear whether the differentiation of OPCs can be regulated by OFS. The goal of this study was to determine if OFS can improve the differentiation of OPCs and promote the recovery of neurological function after SCI in rats. Immature and mature OLs were observed in spinal cord slices through immunofluorescence staining. Levels of adenosine triphosphate (ATP) and the cytokine leukemia inhibitory factor (LIF) were detected by enzyme-linked immunosorbent assay (ELISA). Basso-Beattie-Bresnahan (BBB) scores and transcranial magnetic motor-evoked potentials (tcMMEPs) were used to evaluate the locomotor outcomes of rats after SCI. Our results showed a significant improvement in the differentiation of OPCs and the content of ATP and LIF in the injured spinal cord in the OFS group. Furthermore, BBB scores and tcMMEPs were significantly improved in the rats stimulated by OFS. These findings suggest that OFS can improve the differentiation of OPCs and promote the recovery of neurological function following SCI in rats. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  8. Ba2+- and bupivacaine-sensitive background K+ conductances mediate rapid EPSP attenuation in oligodendrocyte precursor cells.

    Science.gov (United States)

    Chan, Chu-Fang; Kuo, Tzu-Wei; Weng, Ju-Yun; Lin, Yen-Chu; Chen, Ting-Yu; Cheng, Jen-Kun; Lien, Cheng-Chang

    2013-10-01

    Glutamatergic transmission onto oligodendrocyte precursor cells (OPCs) may regulate OPC proliferation, migration and differentiation. Dendritic integration of excitatory postsynaptic potentials (EPSPs) is critical for neuronal functions, and mechanisms regulating dendritic propagation and summation of EPSPs are well understood. However, little is known about EPSP attenuation and integration in OPCs. We developed realistic OPC models for synaptic integration, based on passive membrane responses of OPCs obtained by simultaneous dual whole-cell patch-pipette recordings. Compared with neurons, OPCs have a very low value of membrane resistivity, which is largely mediated by Ba(2+)- and bupivacaine-sensitive background K(+) conductances. The very low membrane resistivity not only leads to rapid EPSP attenuation along OPC processes but also sharpens EPSPs and narrows the temporal window for EPSP summation. Thus, background K(+) conductances regulate synaptic responses and integration in OPCs, thereby affecting activity-dependent neuronal control of OPC development and function.

  9. Overexpression of Polysialylated Neural Cell Adhesion Molecule Improves the Migration Capacity of Induced Pluripotent Stem Cell-Derived Oligodendrocyte Precursors

    NARCIS (Netherlands)

    Czepiel, Marcin; Leicher, Lasse; Becker, Katja; Boddeke, Erik; Copray, Sjef

    2014-01-01

    Cell replacement therapy aiming at the compensation of lost oligodendrocytes and restoration of myelination in acquired or congenital demyelination disorders has gained considerable interest since the discovery of induced pluripotent stem cells (iPSCs). Patient-derived iPSCs provide an inexhaustible

  10. Oscillating field stimulation promotes spinal cord remyelination by inducing differentiation of oligodendrocyte precursor cells after spinal cord injury.

    Science.gov (United States)

    Zhang, Cheng; Zhang, Guanghao; Rong, Wei; Wang, Aihua; Wu, Changzhe; Huo, Xiaolin

    2014-01-01

    Demyelination is part of the cascading secondary injury after the primary insult and contributes to the loss of function after spinal cord injury (SCI). Oligodendrocyte precursor cells (OPCs) are the main remyelinating cells in the central nervous system (CNS). We explored whether oscillating field stimulation (OFS) could efficiently promote OPC differentiation and improve remyelination after SCI. SD rats with SCI induced by the Allen method were randomly divided into two groups, the SCI+OFS group and SCI group. The former group received active stimulator units and the latter group received sham (inoperative) stimulator units. Additionally, rats that only received laminectomy were referred as the sham group. The electric field intensity was 600 μV/mm, and the polarity was alternated every 15 minutes. The results showed that the SCI+OFS rats had significantly less demyelination and better locomotor function recovery after 12-weeks treatment. The OFS treatment significantly increased the number of Gal C-positive OPCs after 2-weeks treatment. Furthermore, these rats had higher protein expression of oligodendroglial transcription factors Olig2 and NKx2.2. These findings suggest OFS can promote locomotor recovery and remyelination in SCI rats and this effect may be related to the improved differentiation of OPCs in the spinal cord.

  11. WIN55,212-2 protects oligodendrocyte precursor cells in stroke penumbra following permanent focal cerebral ischemia in rats

    Institute of Scientific and Technical Information of China (English)

    Jing SUN; Yin-quan FANG; Hong REN; Tao CHEN; Jing-jing GUO; Jun YAN; Shu SONG; Lu-yong ZHANG; Hong LIAO

    2013-01-01

    Aim:To explore whether the synthetic cannabinoid receptor agonist WIN55,212-2 could protect oligodendrocyte precursor cells (OPCs)in stroke penumbra,thereby providing neuroprotection following permanent focal cerebral ischemia in rats.Methods:Adult male SD rats were subjected to permanent middle cerebral artery occlusion (p-MCAO).The animals were administered WIN55,212-2 at 2 h,and sacrificed at 24 h after the ischemic insult.The infarct volumes and brain swelling were assessed.The expression of cannabinoid receptor type 1 (CB1) in the stroke penumbra was examined using Western blot assay.The pathological changes and proliferation of neural glial antigen 2-positive OPCs (NG2+ cells) in the stroke penumbra were studied using immunohistochemistry staining.Results:p-MCAO significantly increased the expression of CB1 within the stroke penumbra with the highest level appearing at 2 h following the ischemic insult.Administration of WIN55,212-2 (9 mg/kg,iv) significantly attenuated the brain swelling,and reduced the infarct volume as well as the number of tau-immunoreactive NG2+ cells (tau-1+/NG2+ cells) in the stroke penumbra.Moreover,WIN55,212-2 significantly promoted the proliferation of NG2+ cells in the stroke penumbra and in the ipsilateral subventricular zone at 24 h following the ischemic insult.Administration of the selective CB1 antagonist rimonabant (1 mg/kg,iv) partially blocked the effects caused by WIN55,212-2.Conclusion:Tau-1 is expressed in NG2+ cells following permanent focal cerebral ischemic injury.Treatment with WIN55,212-2 reduces the number of tau-1+/NG2+ cells and promotes NG2+ cell proliferation in the stroke penumbra,which are mediated partially via CB1 and may contribute to its neuroprotective effects.

  12. The NG2 Proteoglycan Protects Oligodendrocyte Precursor Cells against Oxidative Stress via Interaction with OMI/HtrA2.

    Directory of Open Access Journals (Sweden)

    Frank Maus

    Full Text Available The NG2 proteoglycan is characteristically expressed by oligodendrocyte progenitor cells (OPC and also by aggressive brain tumours highly resistant to chemo- and radiation therapy. Oligodendrocyte-lineage cells are particularly sensitive to stress resulting in cell death in white matter after hypoxic or ischemic insults of premature infants and destruction of OPC in some types of Multiple Sclerosis lesions. Here we show that the NG2 proteoglycan binds OMI/HtrA2, a mitochondrial serine protease which is released from damaged mitochondria into the cytosol in response to stress. In the cytosol, OMI/HtrA2 initiates apoptosis by proteolytic degradation of anti-apoptotic factors. OPC in which NG2 has been downregulated by siRNA, or OPC from the NG2-knockout mouse show an increased sensitivity to oxidative stress evidenced by increased cell death. The proapoptotic protease activity of OMI/HtrA2 in the cytosol can be reduced by the interaction with NG2. Human glioma expressing high levels of NG2 are less sensitive to oxidative stress than those with lower NG2 expression and reducing NG2 expression by siRNA increases cell death in response to oxidative stress. Binding of NG2 to OMI/HtrA2 may thus help protect cells against oxidative stress-induced cell death. This interaction is likely to contribute to the high chemo- and radioresistance of glioma.

  13. Transplantation of PDGF-AA-Overexpressing Oligodendrocyte Precursor Cells Promotes Recovery in Rat Following Spinal Cord Injury

    Science.gov (United States)

    Yao, Zong-Feng; Wang, Ying; Lin, Yu-Hong; Wu, Yan; Zhu, An-You; Wang, Rui; Shen, Lin; Xi, Jin; Qi, Qi; Jiang, Zhi-Quan; Lü, He-Zuo; Hu, Jian-Guo

    2017-01-01

    Our previous study showed that Schwann cells (SCs) promote survival, proliferation and migration of co-transplanted oligodendrocyte progenitor cells (OPCs) and neurological recovery in rats with spinal cord injury (SCI). A subsequent in vitro study confirmed that SCs modulated OPC proliferation and migration by secreting platelet-derived growth factor (PDGF)-AA and fibroblast growth factor-2 (FGF)-2. We also found that PDGF-AA stimulated OPC proliferation and their differentiation into oligodendrocytes (OLs) at later stages. We therefore speculated that PDGF-AA administration can exert the same effect as SC co-transplantation in SCI repair. To test this hypothesis, in this study we investigated the effect of transplanting PDGF-AA-overexpressing OPCs in a rat model of SCI. We found that PDGF-AA overexpression in OPCs promoted their survival, proliferation, and migration and differentiation into OLs in vivo. OPCs overexpressing PDGF-AA were also associated with increased myelination and tissue repair after SCI, leading to the recovery of neurological function. These results indicate that PDGF-AA-overexpressing OPCs may be an effective treatment for SCI.

  14. 少突胶质前体细胞分化的调节机制%The Regulation of Differentiation on Oligodendrocyte Precursor Cells

    Institute of Scientific and Technical Information of China (English)

    蒋萌

    2012-01-01

    In the CNS, oligodendrocytes are responsible for the formation of myelin that surrounds axons. In recent years, oligodendrocyte precursor cells (OPCs) have gained much attention for their potential of self-renew, differentiation, and remyelination of the CNS. The molecular mechanisms controlling OPCs differentiation during development, including oligodendroglial cytoskeleton, transcription, spatiotemporal regulation and axonal inhibition were reviewed.%少突胶质前体细胞形成中枢神经系统轴突的髓鞘.近年来,少突胶质前体细胞(OPC)以具有自我更新、分化及髓鞘化中枢神经系统轴突的潜能而引起关注.本文将综述在发育过程中调控OPC分化的分子机制,主要包括细胞骨架水平、转录水平、时空水平以及轴突水平等方面.

  15. Cerebral cortex demyelination and oligodendrocyte precursor response to experimental autoimmune encephalomyelitis.

    Science.gov (United States)

    Girolamo, Francesco; Ferrara, Giovanni; Strippoli, Maurizio; Rizzi, Marco; Errede, Mariella; Trojano, Maria; Perris, Roberto; Roncali, Luisa; Svelto, Maria; Mennini, Tiziana; Virgintino, Daniela

    2011-09-01

    Experimentally induced autoimmune encephalomyelitis (EAE) in mice provides an animal model that shares many features with human demyelinating diseases such as multiple sclerosis (MS). To what extent the cerebral cortex is affected by the process of demyelination and how the corollary response of the oligodendrocyte lineage is explicated are still not completely known aspects of EAE. By performing a detailed in situ analysis of expression of myelin and oligodendrocyte markers we have identified areas of subpial demyelination in the cerebral cortex of animals with conventionally induced EAE conditions. On EAE-affected cerebral cortices, the distribution and relative abundance of cells of the oligodendrocyte lineage were assessed and compared with control mouse brains. The analysis demonstrated that A2B5(+) glial restricted progenitors (GRPs) and NG2(+)/PDGFR-α(+) oligodendrocyte precursor cells (OPCs) were increased in number during "early" disease, 20 days post MOG immunization, whereas in the "late" disease, 39 days post-immunization, they were strongly diminished, and there was an accompanying reduction in NG2(+)/O4(+) pre-oligodendrocytes and GST-π mature oligodendrocytes. These results, together with the observed steady-state amount of NG2(-)/O4(+) pre-myelinating oligodendrocytes, suggested that oligodendroglial precursors attempted to compensate for the progressive loss of myelin, although these cells appeared to fail to complete the last step of their differentiation program. Our findings confirm that this chronic model of EAE reproduces the features of neocortex pathology in progressive MS and suggest that, despite the proliferative response of the oligodendroglial precursors, the failure to accomplish final differentiation may be a key contributing factor to the impaired remyelination that characterizes these demyelinating conditions. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Strategies for repair of white matter: Influence of osmolarity and microglia on proliferation and apoptosis of oligodendrocyte precursor cells in different basal culture media

    Directory of Open Access Journals (Sweden)

    Karolina eKleinsimlinghaus

    2013-12-01

    Full Text Available The aim of the present study has been to obtain high yields of oligodendrocyte precursor cells (OPCs in culture. This is a first step in facilitation of myelin repair. We show that, in addition to factors, known to promote proliferation, such as basic fibroblast growth factor (FGF-2 and platelet derived growth factor (PDGF the choice of the basal medium exerts a significant influence on the yield of OPCs in cultures from newborn rats. During a culture period of up to 9 days we observed larger numbers of surviving cells in Dulbecco’s Modified Eagle Medium (DMEM and Roswell Park Memorial Institute Medium (RPMI compared with Neurobasal Medium (NB. A larger number of A2B5-positive OPCs was found after 6 days in RPMI based media compared with NB. The percentage of bromodeoxyuridine (BrdU-positive cells was largest in cultures maintained in DMEM and RPMI. The percentage of caspase-3 positive cells was largest in NB, suggesting that this medium inhibits OPC proliferation and favors apoptosis. A difference between NB and DMEM as well as RPMI is the reduced Na+-content. The addition of equiosmolar supplements of mannitol or NaCl to NB medium rescued the BrdU-incorporation rate. This suggested that the osmolarity influences the proliferation of OPCs. Plating density as well as residual microglia influence OPC survival, BrdU incorporation and caspase-3 expression. We found, that high density cultures secrete factors that inhibit BrdU incorporation whereas the presence of additional microglia induces an increase in caspase-3 positive cells, indicative of enhanced apoptosis. An enhanced number of microglia could thus also explain the stronger inhibition of OPC differentiation observed in high density cultures in response to treatment with the cytokines TNF-a and IFN-g.We conclude that a maximal yield of OPCs is obtained in a medium of an osmolarity higher than 280 mOsm plated at a relatively low density in the presence of as little microglia as technically

  17. Oligodendrocyte differentiation and implantation : new insights for remyelinating cell therapy

    NARCIS (Netherlands)

    Sher, Falak; Balasubramaniyan, Veerakumar; Boddeke, Erik; Copray, Sjef

    2008-01-01

    Purpose of review Recent research on oligodendrocyte development has yielded new insights on the involvement of morphogens and differentiation factors in oligodendrogenesis. This knowledge has improved strategies to control neural stem cell-derived oligodendrocyte differentiation and functional matu

  18. Survival and Functionality of Human Induced Pluripotent Stem Cell-Derived Oligodendrocytes in a Nonhuman Primate Model for Multiple Sclerosis

    NARCIS (Netherlands)

    Thiruvalluvan, Arun; Czepiel, Marcin; Kap, Yolanda A; Mantingh-Otter, Ietje; Vainchtein, Ilia; Kuipers, Jeroen; Bijlard, Marjolein; Baron, Wia; Giepmans, Ben; Brück, Wolfgang; 't Hart, Bert A; Boddeke, Erik; Copray, Sjef

    2016-01-01

    : Fast remyelination by endogenous oligodendrocyte precursor cells (OPCs) is essential to prevent axonal and subsequent retrograde neuronal degeneration in demyelinating lesions in multiple sclerosis (MS). In chronic lesions, however, the remyelination capacity of OPCs becomes insufficient. Cell the

  19. Signalling pathways that inhibit the capacity of precursor cells for myelin repair.

    Science.gov (United States)

    Sabo, Jennifer K; Cate, Holly S

    2013-01-07

    In demyelinating disorders such as Multiple Sclerosis (MS), targets of injury are myelin and oligodendrocytes, leading to severe neurological dysfunction. Regenerative therapies aimed at promoting oligodendrocyte maturation and remyelination are promising strategies for treatment in demyelinating disorders. Endogenous precursor cells or exogenous transplanted cells are potential sources for remyelinating oligodendrocytes in the central nervous system (CNS). Several signalling pathways have been implicated in regulating the capacity of these cell populations for myelin repair. Here, we review neural precursor cells and oligodendrocyte progenitor cells as potential sources for remyelinating oligodendrocytes and evidence for the functional role of key signalling pathways in inhibiting regeneration from these precursor cell populations.

  20. Signalling Pathways that Inhibit the Capacity of Precursor Cells for Myelin Repair

    Directory of Open Access Journals (Sweden)

    Jennifer K. Sabo

    2013-01-01

    Full Text Available In demyelinating disorders such as Multiple Sclerosis (MS, targets of injury are myelin and oligodendrocytes, leading to severe neurological dysfunction. Regenerative therapies aimed at promoting oligodendrocyte maturation and remyelination are promising strategies for treatment in demyelinating disorders. Endogenous precursor cells or exogenous transplanted cells are potential sources for remyelinating oligodendrocytes in the central nervous system (CNS. Several signalling pathways have been implicated in regulating the capacity of these cell populations for myelin repair. Here, we review neural precursor cells and oligodendrocyte progenitor cells as potential sources for remyelinating oligodendrocytes and evidence for the functional role of key signalling pathways in inhibiting regeneration from these precursor cell populations.

  1. Corticosteroids reverse cytokine-induced block of survival and differentiation of oligodendrocyte progenitor cells from rats

    Directory of Open Access Journals (Sweden)

    Marx Romy

    2008-09-01

    Full Text Available Abstract Background Periventricular leukomalacia (PVL is a frequent complication of preterm delivery. Proinflammatory cytokines, such as interferon-γ (IFN-γ and tumor necrosis factor α (TNF-α released from astrocytes and microglia activated by infection or ischemia have previously been shown to impair survival and maturation of oligodendrocyte progenitors and could thus be considered as potential factors contributing to the generation of this disease. The first goal of the present study was to investigate whether exposure of oligodendrocyte precursors to these cytokines arrests the maturation of ion currents in parallel to its effects on myelin proteins and morphological maturation. Secondly, in the search for agents, that can protect differentiating oligodendrocyte precursor cells from cytokine-induced damage we investigated effects of coapplications of corticosteroids with proinflammatory cytokines on the subsequent survival and differentiation of oligodendrocyte progenitor cells. Methods To exclude influences from factors released from other cell types purified cultures of oligodendrocyte precursors were exposed to cytokines and/or steroids and allowed to differentiate for further 6 days in culture. Changes in membrane surface were investigated with capacitance recordings and Scanning Ion Conductance Microscopy. Na+- and K+- currents were investigated using whole cell patch clamp recordings. The expression of myelin specific proteins was investigated using western blots and the precursor cells were identified using immunostaining with A2B5 antibodies. Results Surviving IFN-γ and TNF-α treated cells continued to maintain voltage-activated Na+- and K+ currents characteristic for the immature cells after 6 days in differentiation medium. Corticosterone, dihydrocorticosterone and, most prominently dexamethasone, counteracted the deleterious effects of IFN-γ and TNF-α on cell survival, A2B5-immunostaining and expression of myelin basic

  2. Sox10 directs neural stem cells toward the oligodendrocyte lineage by decreasing Suppressor of Fused expression

    Science.gov (United States)

    Pozniak, Christine D.; Langseth, Abraham J.; Dijkgraaf, Gerrit J. P.; Choe, Youngshik; Werb, Zena; Pleasure, Samuel J.

    2010-01-01

    Oligodendrocyte precursor cells (OPCs) are lineage-restricted progenitors generally limited in vivo to producing oligodendrocytes. Mechanisms controlling genesis of OPCs are of interest because of their importance in myelin development and their potential for regenerative therapies in multiple sclerosis and dysmyelinating syndromes. We show here that the SoxE transcription factors (comprising Sox8, 9, and 10) induce multipotent neural precursor cells (NPCs) from the early postnatal subventricular zone (SVZ) to become OPCs in an autonomous manner. We performed a chromatin immunoprecipitation-based bioinformatic screen and identified Suppressor of Fused (Sufu) as a direct target of repression by Sox10. In vitro, overexpression of Sufu blocked OPC production, whereas RNAi-mediated inhibition augmented OPC production. Furthermore, mice heterozygous for Sufu have increased numbers of OPCs in the telencephalon during development. We conclude that Sox10 acts to restrict the potential of NPCs toward the oligodendrocyte lineage in part by regulating the expression of Sufu. PMID:21098272

  3. Endogenous GABA controls oligodendrocyte lineage cell number, myelination, and CNS internode length

    DEFF Research Database (Denmark)

    Hamilton, Nicola B; Clarke, Laura E; Arancibia-Carcamo, I Lorena;

    2016-01-01

    Adjusting the thickness and internodal length of the myelin sheath is a mechanism for tuning the conduction velocity of axons to match computational needs. Interactions between oligodendrocyte precursor cells (OPCs) and developing axons regulate the formation of myelin around axons. We now show, ...

  4. 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.

  5. Axonal degeneration stimulates the formation of NG2+ cells and oligodendrocytes in the mouse

    DEFF Research Database (Denmark)

    Nielsen, Helle Hvilsted; Ladeby, Rune; Drøjdahl, Nina;

    2006-01-01

    Proliferation of the adult NG2-expressing oligodendrocyte precursor cells has traditionally been viewed as a remyelination response ensuing from destruction of myelin and oligodendrocytes, and not to the axonal pathology that is also a characteristic of demyelinating disease. To better understand...... the response of the NG2+ cells to the different components of demyelinating pathology, we investigated the response of adult NG2+ cells to axonal degeneration in the absence of primary myelin or oligodendrocyte pathology. Axonal degeneration was induced in the hippocampal dentate gyrus of adult mice...... by transection of the entorhino-dentate perforant path projection. The acutely induced degeneration of axons and terminals resulted in a prompt response of NG2+ cells, consisting of morphological transformation, cellular proliferation, and upregulation of NG2 expression days 2-3 after surgery. This was followed...

  6. Enhancement of oligodendrocyte differentiation from murine embryonic stem cells by an activator of gp130 signaling.

    Science.gov (United States)

    Zhang, Peilin; Chebath, Judith; Lonai, Peter; Revel, Michel

    2004-01-01

    Embryonic stem (ES) cells derived from the inner cell mass of blastocyst-stage embryos are a potential large scale source of oligodendrocytes and of their progenitors for transplantation into the central nervous system for the repair of demyelinating lesions. We found previously that interleukin-6 (IL-6) fused to its soluble receptor (IL-6R), a potent activator of the gp130 receptor, induces myelin gene expression in Schwann cells of embryonic dorsal root ganglia. Like leukemia inhibitory factor, IL-6R/IL-6 inhibits the differentiation of murine ES cells into embryoid bodies. In the present study, we show that this recombinant cytokine may be efficiently used to stimulate the differentiation of oligodendrocytes if added to ES cell-derived neural precursors. IL-6R/IL-6 leads to an increase in early chondroitin sulfate proteoglycan positive and late O4 positive progenitors and to a stimulation of maturation into O1 and myelin basic protein expressing oligodendrocytes. Expression of the genes for transcription factor genes Olig-1 and Sox10, which appear early in the oligodendrocyte lineage, was stimulated by IL-6R/IL-6 addition. We conclude that this cytokine can significantly enhance the derivation of oligodendrocytes from ES cells.

  7. 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

  8. Oligodendrocyte-like cell transplantation for acute spinal cord injury

    Institute of Scientific and Technical Information of China (English)

    Yongtao Xu; Anmin Chen; Feng Li; Hougeng Lu

    2011-01-01

    In this study, we used insulin-like growth factor-1 to induce bone marrow mesenchymal stem cells (MSCs) to differentiate into oligodendrocyte-like cells. Cell surface marker identification showed that they expressed myelin basic protein and galactosylceramide, two specific markers of oligodendrocytes. These cells were transplanted into rats with acute spinal cord injury at T10. At 8 weeks post-implantation, oligodendrocyte-like cells were observed to have survived at the injury site. The critical angle of the inclined plane, and Basso, Beattie and Bresnahan scores were all increased. Furthermore, latencies of motion-evoked and somatosensory-evoked potentials were decreased. These results demonstrate that transplantation of oligodendrocytic-induced MSCs promote functional recovery of injured spinal cord.

  9. Secretome analysis of human oligodendrocytes derived from neural stem cells.

    Directory of Open Access Journals (Sweden)

    Woo Kyung Kim

    Full Text Available In this study, we investigated the secretome of human oligodendrocytes (F3.Olig2 cells generated from human neural stem cells by transduction with the gene encoding the Olig2 transcription factor. Using mRNA sequencing and protein cytokine arrays, we identified a number of biologically important secretory proteins whose expression has not been previously reported in oligodendrocytes. We found that F3.Olig2 cells secrete IL-6, PDGF-AA, GRO, GM-CSF, and M-CSF, and showed prominent expression of their corresponding receptors. Co-expression of ligands and receptors suggests that autocrine signaling loops may play important roles in both differentiation and maintenance of oligodendrocytes. We also found that F3.Olig2 cells secrete matrix metalloproteinases and matrix metalloproteinase-associated proteins associated with functional competence of oligodendrocytes. The results of our secretome analysis provide insights into the functional and molecular details of human oligodendrocytes. To the best of our knowledge, this is the first systematic analysis of the secretome of oligodendrocytes.

  10. Oligodendrocyte plasticity with an intact cell body in vitro.

    Directory of Open Access Journals (Sweden)

    Manabu Makinodan

    Full Text Available Demyelination is generally regarded as a consequence of oligodendrocytic cell death. Oligodendrocyte processes that form myelin sheaths may, however, degenerate and regenerate independently of the cell body, in which case cell death does not necessarily occur. We provide here the first evidence of retraction and regeneration of oligodendrocyte processes with no cell death in vitro, using time-lapse imaging. When processes were severed mechanically in vitro, the cells did not undergo cell death and the processes regenerated in 36 h. In a separate experiment, moderate N-methyl-D-aspartate (NMDA stimuli caused process retraction without apparent cell death, and the processes regained their elaborate morphology after NMDA was removed from the culture medium. These results strongly suggest that demyelination and remyelination can take place without concomitant cell death, at least in vitro. Process regeneration may therefore become a target for future therapy of demyelinating disorders.

  11. Human induced pluripotent stem cells differentiation into oligodendrocyte progenitors and transplantation in a rat model of optic chiasm demyelination.

    Directory of Open Access Journals (Sweden)

    Alireza Pouya

    Full Text Available BACKGROUND: This study aims to differentiate human induced pluripotent stem cells (hiPSCs into oligodendrocyte precursors and assess their recovery potential in a demyelinated optic chiasm model in rats. METHODOLOGY/PRINCIPAL FINDINGS: We generated a cell population of oligodendrocyte progenitors from hiPSCs by using embryoid body formation in a defined medium supplemented with a combination of factors, positive selection and mechanical enrichment. Real-time polymerase chain reaction and immunofluorescence analyses showed that stage-specific markers, Olig2, Sox10, NG2, PDGFRα, O4, A2B5, GalC, and MBP were expressed following the differentiation procedure, and enrichment of the oligodendrocyte lineage. These results are comparable with the expression of stage-specific markers in human embryonic stem cell-derived oligodendrocyte lineage cells. Transplantation of hiPSC-derived oligodendrocyte progenitors into the lysolecithin-induced demyelinated optic chiasm of the rat model resulted in recovery from symptoms, and integration and differentiation into oligodendrocytes were detected by immunohistofluorescence staining against PLP and MBP, and measurements of the visual evoked potentials. CONCLUSIONS/SIGNIFICANCE: These results showed that oligodendrocyte progenitors generated efficiently from hiPSCs can be used in future biomedical studies once safety issues have been overcome.

  12. 急性一氧化碳中毒对大鼠少突胶质前体细胞的影响%Effect of acute carbon monoxide poisoning on oligodendrocyte precursor cells in rats

    Institute of Scientific and Technical Information of China (English)

    孙瑞佼; 郭大志; 李航; 李铭鑫; 胡慧军; 潘晓雯

    2015-01-01

    Western blot .Results:Immuno‐histochemistry demonstrated that the expression levels of MBP and NG 2 began to decrease at 1st day after ACOP , and there was statistically significant difference in the integral optical density (IOD) level of MBP and NG2 as com‐pared with the control group at 3rd day after ACOP (P<0 .05) .Results of Western blot showed that as compared with the control group ,the expression levels of MBP and NG2 were decreased at 1st day after ACOP ,and decreased further at 3rd day (P<0 .05) .Conclusion:Demyelination and damage of oligodendrocyte precursor cells occurred in the brain tissue of rats after ACOP .

  13. Transplantation of human oligodendrocyte progenitor cells in an animal model of diffuse traumatic axonal injury: survival and differentiation.

    Science.gov (United States)

    Xu, Leyan; Ryu, Jiwon; Hiel, Hakim; Menon, Adarsh; Aggarwal, Ayushi; Rha, Elizabeth; Mahairaki, Vasiliki; Cummings, Brian J; Koliatsos, Vassilis E

    2015-05-14

    Diffuse axonal injury is an extremely common type of traumatic brain injury encountered in motor vehicle crashes, sports injuries, and in combat. Although many cases of diffuse axonal injury result in chronic disability, there are no current treatments for this condition. Its basic lesion, traumatic axonal injury, has been aggressively modeled in primate and rodent animal models. The inexorable axonal and perikaryal degeneration and dysmyelination often encountered in traumatic axonal injury calls for regenerative therapies, including therapies based on stem cells and precursors. Here we explore the proof of concept that treatments based on transplants of human oligodendrocyte progenitor cells can replace or remodel myelin and, eventually, contribute to axonal regeneration in traumatic axonal injury. We derived human oligodendrocyte progenitor cells from the human embryonic stem cell line H9, purified and characterized them. We then transplanted these human oligodendrocyte progenitor cells into the deep sensorimotor cortex next to the corpus callosum of nude rats subjected to traumatic axonal injury based on the impact acceleration model of Marmarou. We explored the time course and spatial distribution of differentiation and structural integration of these cells in rat forebrain. At the time of transplantation, over 90 % of human oligodendrocyte progenitor cells expressed A2B5, PDGFR, NG2, O4, Olig2 and Sox10, a profile consistent with their progenitor or early oligodendrocyte status. After transplantation, these cells survived well and migrated massively via the corpus callosum in both injured and uninjured brains. Human oligodendrocyte progenitor cells displayed a striking preference for white matter tracts and were contained almost exclusively in the corpus callosum and external capsule, the striatopallidal striae, and cortical layer 6. Over 3 months, human oligodendrocyte progenitor cells progressively matured into myelin basic protein(+) and adenomatous

  14. Human Traumatic Brain Injury Results in Oligodendrocyte Death and Increases the Number of Oligodendrocyte Progenitor Cells.

    Science.gov (United States)

    Flygt, Johanna; Gumucio, Astrid; Ingelsson, Martin; Skoglund, Karin; Holm, Jonatan; Alafuzoff, Irina; Marklund, Niklas

    2016-06-01

    Oligodendrocyte (OL) death may contribute to white matter pathology, a common cause of network dysfunction and persistent cognitive problems in patients with traumatic brain injury (TBI). Oligodendrocyte progenitor cells (OPCs) persist throughout the adult CNS and may replace dead OLs. OL death and OPCs were analyzed by immunohistochemistry of human brain tissue samples, surgically removed due to life-threatening contusions and/or focal brain swelling at 60.6 ± 75 hours (range 4-192 hours) postinjury in 10 severe TBI patients (age 51.7 ± 18.5 years). Control brain tissue was obtained postmortem from 5 age-matched patients without CNS disorders. TUNEL and CC1 co-labeling was used to analyze apoptotic OLs, which were increased in injured brain tissue (p number of single-labeled Olig2, A2B5, NG2, and PDGFR-α-positive cells, numbers of Olig2 and A2B5 co-labeled cells were increased in TBI samples (p < 0.05); this was inversely correlated with time from injury to surgery (r = -0.8, p < 0.05). These results indicate that severe focal human TBI results in OL death and increases in OPCs postinjury, which may influence white matter function following TBI.

  15. WIN55, 212-2 promotes differentiation of oligodendrocyte precursor cells and improve remyelination through regulation of the phosphorylation level of the ERK 1/2 via cannabinoid receptor 1 after stroke-induced demyelination.

    Science.gov (United States)

    Sun, Jing; Fang, Yinquan; Chen, Tao; Guo, Jingjing; Yan, Jun; Song, Shu; Zhang, Luyong; Liao, Hong

    2013-01-23

    In stroke, a common cause of neurological disability in adults is that the myelin sheaths are lost through the injury or death of mature oligodendrocytes, and the failure of remyelination may be often due to insufficient proliferation and differentiation of oligodendroglial progenitors. In the current study, we used middle cerebral artery occlusion (MCAO) to induced transient focal cerebral ischemia, and found that WIN55, 212-2 augmented actively proliferating oligodendrocytes measured by CC1 immunoreactive cells within the peri-infarct areas. To establish whether these effects were associated with changes in myelin formation, we analyzed the expression of myelin basic protein (MBP) and myelin ultrastructure. We found that WIN55, 212-2 showed more extensive remyelination than vehicle at 14 days post injection (dpi). The extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/MAPK) signaling pathway may be involved in OPCs differentiation. To determine the regulatory effect of WIN55, 212-2 post-treatment on phospho-ERK 1/2 (p-ERK 1/2) after ischemia/reperfusion, Western blot analysis was performed. We found that WIN55, 212-2 regulated the phosphorylation level of the ERK 1/2 to promote OPCs survival and differentiation. Notably, cannabinoid receptor 1 is coupled to the activation of the ERK cascade. Following rimonabant combined treatment, the effect of WIN55, 212-2 on regulating the phosphorylation level of the ERK 1/2 was reversed, and the effect of accelerated myelin formation was partially inhibited. Together, we first found that WIN55, 212-2 promoted OPCs differentiation and remyelination through regulation of the level of the p-ERK 1/2 via cannabinoid receptor 1.

  16. Neural and Oligodendrocyte Progenitor Cells: Transferrin Effects on Cell Proliferation

    Directory of Open Access Journals (Sweden)

    Lucas Silvestroff

    2013-02-01

    Full Text Available NSC (neural stem cells/NPC (neural progenitor cells are multipotent and self-renew throughout adulthood in the SVZ (subventricular zone of the mammalian CNS (central nervous system. These cells are considered interesting targets for CNS neurodegenerative disorder cell therapies, and understanding their behaviour in vitro is crucial if they are to be cultured prior to transplantation. We cultured the SVZ tissue belonging to newborn rats under the form of NS (neurospheres to evaluate the effects of Tf (transferrin on cell proliferation. The NS were heterogeneous in terms of the NSC/NPC markers GFAP (glial fibrillary acidic protein, Nestin and Sox2 and the OL (oligodendrocyte progenitor markers NG2 (nerve/glia antigen 2 and PDGFRα (platelet-derived growth factor receptor α. The results of this study indicate that aTf (apoTransferrin is able to increase cell proliferation of SVZ-derived cells in vitro, and that these effects were mediated at least in part by the TfRc1 (Tf receptor 1. Since OPCs (oligodendrocyte progenitor cells represent a significant proportion of the proliferating cells in the SVZ-derived primary cultures, we used the immature OL cell line N20.1 to show that Tf was able to augment the proliferation rate of OPC, either by adding aTf to the culture medium or by overexpressing rat Tf in situ. The culture medium supplemented with ferric iron, together with aTf, increased the DNA content, while ferrous iron did not. The present work provides data that could have a potential application in human cell replacement therapies for neurodegenerative disease and/or CNS injury that require the use of in vitro amplified NPCs.

  17. Erythropoietin (EPO) increases myelin gene expression in CG4 oligodendrocyte cells through the classical EPO receptor.

    Science.gov (United States)

    Cervellini, Ilaria; Annenkov, Alexander; Brenton, Thomas; Chernajovsky, Yuti; Ghezzi, Pietro; Mengozzi, Manuela

    2013-08-28

    Erythropoietin (EPO) has protective effects in neurodegenerative and neuroinflammatory diseases, including in animal models of multiple sclerosis, where EPO decreases disease severity. EPO also promotes neurogenesis and is protective in models of toxic demyelination. In this study, we asked whether EPO could promote neurorepair by also inducing remyelination. In addition, we investigated whether the effect of EPO could be mediated by the classical erythropoietic EPO receptor (EPOR), since it is still questioned if EPOR is functional in nonhematopoietic cells. Using CG4 cells, a line of rat oligodendrocyte precursor cells, we found that EPO increases the expression of myelin genes (myelin oligodendrocyte glycoprotein [MOG] and myelin basic protein [MBP]). EPO had no effect in wild-type CG4 cells, which do not express EPOR, whereas it increased MOG and MBP expression in cells engineered to overexpress EPOR (CG4-EPOR). This was reflected in a marked increase in MOG protein levels, as detected by Western blot. In these cells, EPO induced by 10-fold the early growth response gene 2 (Egr2), which is required for peripheral myelination. However, Egr2 silencing with a siRNA did not reverse the effect of EPO, indicating that EPO acts through other pathways. In conclusion, EPO induces the expression of myelin genes in oligodendrocytes and this effect requires the presence of EPOR. This study demonstrates that EPOR can mediate neuroreparative effects.

  18. Pericytes Stimulate Oligodendrocyte Progenitor Cell Differentiation during CNS Remyelination

    Directory of Open Access Journals (Sweden)

    Alerie Guzman De La Fuente

    2017-08-01

    Full Text Available The role of the neurovascular niche in CNS myelin regeneration is incompletely understood. Here, we show that, upon demyelination, CNS-resident pericytes (PCs proliferate, and parenchymal non-vessel-associated PC-like cells (PLCs rapidly develop. During remyelination, mature oligodendrocytes were found in close proximity to PCs. In Pdgfbret/ret mice, which have reduced PC numbers, oligodendrocyte progenitor cell (OPC differentiation was delayed, although remyelination proceeded to completion. PC-conditioned medium accelerated and enhanced OPC differentiation in vitro and increased the rate of remyelination in an ex vivo cerebellar slice model of demyelination. We identified Lama2 as a PC-derived factor that promotes OPC differentiation. Thus, the functional role of PCs is not restricted to vascular homeostasis but includes the modulation of adult CNS progenitor cells involved in regeneration.

  19. A Minimally-invasive Blood-derived Biomarker of Oligodendrocyte Cell-loss in Multiple Sclerosis.

    Science.gov (United States)

    Olsen, John A; Kenna, Lauren A; Tipon, Regine C; Spelios, Michael G; Stecker, Mark M; Akirav, Eitan M

    2016-08-01

    Multiple sclerosis (MS) is a neurodegenerative disease of the central nervous system (CNS). Minimally invasive biomarkers of MS are required for disease diagnosis and treatment. Differentially methylated circulating-free DNA (cfDNA) is a useful biomarker for disease diagnosis and prognosis, and may offer to be a viable approach for understanding MS. Here, methylation-specific primers and quantitative real-time PCR were used to study methylation patterns of the myelin oligodendrocyte glycoprotein (MOG) gene, which is expressed primarily in myelin-producing oligodendrocytes (ODCs). MOG-DNA was demethylated in O4(+) ODCs in mice and in DNA from human oligodendrocyte precursor cells (OPCs) when compared with other cell types. In the cuprizone-fed mouse model of demyelination, ODC derived demethylated MOG cfDNA was increased in serum and was associated with tissue-wide demyelination, demonstrating the utility of demethylated MOG cfDNA as a biomarker of ODC death. Collected sera from patients with active (symptomatic) relapsing-remitting MS (RRMS) demonstrated a higher signature of demethylated MOG cfDNA when compared with patients with inactive disease and healthy controls. Taken together, these results offer a minimally invasive approach to measuring ODC death in the blood of MS patients that may be used to monitor disease progression.

  20. 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.

  1. Fyn tyrosine kinase regulates oligodendroglial cell development but is not required for morphological differentiation of oligodendrocytes.

    Science.gov (United States)

    Sperber, B R; McMorris, F A

    2001-02-15

    The non-receptor protein tyrosine kinase Fyn, which is a member of the Src family of kinases, has been shown to be essential for normal myelination and has been suggested to play a role in oligodendrocyte development. However, oligodendrocyte development has not been studied directly in cells lacking Fyn. Additionally, because Fyn is expressed in neurons as well as oligodendrocytes, it is possible that normal myelination requires Fyn expression in neurons but not in oligodendrocytes. To address these issues, we analyzed the development of oligodendrocytes in neuron-free glial cell cultures from fyn(-/-) mice that express no Fyn protein. We observed that oligodendrocytes develop to the stage where they elaborate an extensive network of membranous processes and express the antigenic components of mature oligodendrocytes in the complete absence of Fyn. However, as compared with fyn(+/+) controls, fewer oligodendroglia developed in fyn(-/-) cell cultures, and a smaller proportion of them matured to the stage characterized by a high degree of morphological complexity. In addition, we found that insulin-like growth factor-I, a potent stimulator of oligodendrocyte development, failed to stimulate morphological maturation of fyn(-/-) oligodendroglia. The pyrazolopyrimidine PP2, believed to be a selective inhibitor of Fyn, did not prevent the development of morphologically complex oligodendrocytes. Unexpectedly, however, it was toxic to both fyn(+/+) and fyn(-/-) glial cells, indicating that this class of inhibitors can have significant effects that are independent of Fyn.

  2. Direct and indirect effects of immune and central nervous system-resident cells on human oligodendrocyte progenitor cell differentiation.

    Science.gov (United States)

    Moore, Craig S; Cui, Qiao-Ling; Warsi, Nebras M; Durafourt, Bryce A; Zorko, Nika; Owen, David R; Antel, Jack P; Bar-Or, Amit

    2015-01-15

    In multiple sclerosis, successful remyelination within the injured CNS is largely dependent on the survival and differentiation of oligodendrocyte progenitor cells. During inflammatory injury, oligodendrocytes and oligodendrocyte progenitor cells within lesion sites are exposed to secreted products derived from both infiltrating immune cell subsets and CNS-resident cells. Such products may be considered either proinflammatory or anti-inflammatory and have the potential to contribute to both injury and repair processes. Within the CNS, astrocytes also contribute significantly to oligodendrocyte biology during development and following inflammatory injury. The overall objective of the current study was to determine how functionally distinct proinflammatory and anti-inflammatory human immune cell subsets, implicated in multiple sclerosis, can directly and/or indirectly (via astrocytes) impact human oligodendrocyte progenitor cell survival and differentiation. Proinflammatory T cell (Th1/Th17) and M1-polarized myeloid cell supernatants had a direct cytotoxic effect on human A2B5(+) neural progenitors, resulting in decreased O4(+) and GalC(+) oligodendrocyte lineage cells. Astrocyte-conditioned media collected from astrocytes pre-exposed to the same proinflammatory supernatants also resulted in decreased oligodendrocyte progenitor cell differentiation without an apparent increase in cell death and was mediated through astrocyte-derived CXCL10, yet this decrease in differentiation was not observed in the more differentiated oligodendrocytes. Th2 and M2 macrophage or microglia supernatants had neither a direct nor an indirect impact on oligodendrocyte progenitor cell differentiation. We conclude that proinflammatory immune cell responses can directly and indirectly (through astrocytes) impact the fate of immature oligodendrocyte-lineage cells, with oligodendrocyte progenitor cells more vulnerable to injury compared with mature oligodendrocytes.

  3. 少突胶质前体细胞移植治疗对大鼠脊髓损伤轴突髓鞘化的影响%Axonal myelination in response to transplantation of oligodendrocyte precursor cells after spinal cord injury in a rat model

    Institute of Scientific and Technical Information of China (English)

    吴波; 孙磊; 任先军

    2010-01-01

    Objective To investigate the effects of transplantation of oligodendrocyte precursor cells (OPCs) on axonal myelination after spinal cord injury in a rat model. Methods A rat model of spinal cord injury at the tenth thoracic vertebral level (T10) was produced by Allen weight-drop impact method. OPCs implantation was performed at the subacute stage of spinal cord injury. Effects of OPCs transplantation on axonal myelination after spinal cord injury were evaluated by HE staining, immunohistochemistry, myelin staining and transmission electron microscopy. Results The implanted cells were still observed in lesioned segments of spinal cord eight weeks after transplantation. The results of HE staining clearly showed better structure of spinal cord in OPCs-transplanted group than that of control group.Myelin staining also demonstrated that the amount of myelin in white matter of lesioned cord in the OPCs-transplanted group (7 802.42 ± 1085.58) was higher than that of the control group (5 055.98 ± 916.74)(P <0.01 ). Expression of myelin basic protein (MBP) was significantly increased in the OPCs-trans-planted group (8 544.44 ±812.78) as compared with that of the control group (5 243.83 ±808.27)(P<0.01). Moreover, transmission electron microscopy further confirmed the improvement of micro-structure of myelination in OPCs-treated rats. Conclusion OPCs transplantation can improve axonal myelination in rat with spinal cord injury.%目的 探讨少突胶质前体细胞(oligodendrocyte precursor cells,OPCs)移植治疗对大鼠脊髓损伤轴突髓鞘化的影响.方法 采用Allen法制作大鼠T10脊髓损伤模型,亚急性期OPCs移植治疗.通过HE染色、免疫组化染色、髓鞘染色及透射电镜观察等方法,研究OPCs移植治疗对大鼠脊髓损伤轴突髓鞘化的影响.结果 移植术后8周时大鼠损伤脊髓内检测到移植细胞分布,HE染色显示OPCs移植组大鼠脊髓组织结构较对照组改善,勒克司坚牢蓝(LFB)髓鞘染色

  4. Metabolic aspects of Neuronal – Oligodendrocytic - Astrocytic (NOA interactions

    Directory of Open Access Journals (Sweden)

    Ana I Amaral

    2013-05-01

    Full Text Available Whereas astrocytes have been in the limelight on the metabolic glucose interaction scene for a while, oligodendrocytes are still waiting for a place. We would like to call oligodendrocyte interaction with astrocytes and neurons: NOA (neuron – oligodendrocyte – astrocyte interactions. One of the reasons to find out more about oligodendrocyte interaction with neurons and astrocytes is to detect markers of healthy oligodendrocyte metabolism, to be used in diagnosis and treatment assessment in diseases such as Perinatal hypoxic-ischemic encephalopathy and multiple sclerosis in which oligodendrocyte function is impaired, possibly due to glutamate toxicity. Glutamate receptors are expressed in oligodendrocytes and also vesicular glutamate release in the white matter has received considerable attention. It is also important to establish if the glial precursor cells recruited to damaged areas are developing oligodendrocyte characteristics or those of astrocytes. Thus, it is important to study astrocytes and oligodendrocytes separately to be able to differentiate between them. This is of particular importance in the white matter where the number of oligodendrocytes is considerable. The present review summarizes the not very extensive information published on glucose metabolism in oligodendrocytes in an attempt to stimulate research into this important field.

  5. Transient expression of Olig1 initiates the differentiation of neural stem cells into oligodendrocyte progenitor cells

    NARCIS (Netherlands)

    Balasubramaniyan, [No Value; Timmer, N; Kust, B; Boddeke, E; Copray, S

    2004-01-01

    In order to develop an efficient strategy to induce the in vitro differentiation of neural stem cells (NSCs) into oligodendrocyte progenitor cells (OPCs), NSCs were isolated from E14 mice and grown in medium containing epidermal growth factor and fibroblast growth factor (FGF). Besides supplementing

  6. Epigenetic Modulation of Human Induced Pluripotent Stem Cell Differentiation to Oligodendrocytes

    Directory of Open Access Journals (Sweden)

    Panagiotis Douvaras

    2016-04-01

    Full Text Available Pluripotent stem cells provide an invaluable tool for generating human, disease-relevant cells. Multiple sclerosis is an inflammatory demyelinating disease of the central nervous system, characterized by myelin damage. Oligodendrocytes are the myelinating cells of the central nervous system (CNS; they differentiate from progenitor cells, and their membranes ensheath axons, providing trophic support and allowing fast conduction velocity. The current understanding of oligodendrocyte biology was founded by rodent studies, where the establishment of repressive epigenetic marks on histone proteins, followed by activation of myelin genes, leads to lineage progression. To assess whether this epigenetic regulation is conserved across species, we differentiated human embryonic and induced pluripotent stem cells to oligodendrocytes and asked whether similar histone marks and relative enzymatic activities could be detected. The transcriptional levels of enzymes responsible for methylation and acetylation of histone marks were analyzed during oligodendrocyte differentiation, and the post-translational modifications on histones were detected using immunofluorescence. These studies showed that also in human cells, differentiation along the oligodendrocyte lineage is characterized by the acquisition of multiple repressive histone marks, including deacetylation of lysine residues on histone H3 and trimethylation of residues K9 and K27. These data suggest that the epigenetic modulation of oligodendrocyte identity is highly conserved across species.

  7. FGF-2 signal promotes proliferation of cerebellar progenitor cells and their oligodendrocytic differentiation at early postnatal stage

    Energy Technology Data Exchange (ETDEWEB)

    Naruse, Masae; Shibasaki, Koji; Ishizaki, Yasuki, E-mail: yasukiishizaki@gunma-u.ac.jp

    2015-08-07

    The origins and developmental regulation of cerebellar oligodendrocytes are largely unknown, although some hypotheses of embryonic origins have been suggested. Neural stem cells exist in the white matter of postnatal cerebellum, but it is unclear whether these neural stem cells generate oligodendrocytes at postnatal stages. We previously showed that cerebellar progenitor cells, including neural stem cells, widely express CD44 at around postnatal day 3. In the present study, we showed that CD44-positive cells prepared from the postnatal day 3 cerebellum gave rise to neurospheres, while CD44-negative cells prepared from the same cerebellum did not. These neurospheres differentiated mainly into oligodendrocytes and astrocytes, suggesting that CD44-positive neural stem/progenitor cells might generate oligodendrocytes in postnatal cerebellum. We cultured CD44-positive cells from the postnatal day 3 cerebellum in the presence of signaling molecules known as mitogens or inductive differentiation factors for oligodendrocyte progenitor cells. Of these, only FGF-2 promoted survival and proliferation of CD44-positive cells, and these cells differentiated into O4+ oligodendrocytes. Furthermore, we examined the effect of FGF-2 on cerebellar oligodendrocyte development ex vivo. FGF-2 enhanced proliferation of oligodendrocyte progenitor cells and increased the number of O4+ and CC1+ oligodendrocytes in slice cultures. These results suggest that CD44-positive cells might be a source of cerebellar oligodendrocytes and that FGF-2 plays important roles in their development at an early postnatal stage. - Highlights: • CD44 is expressed in cerebellar neural stem/progenitor cells at postnatal day 3 (P3). • FGF-2 promoted proliferation of CD44-positive progenitor cells from P3 cerebellum. • FGF-2 promoted oligodendrocytic differentiation of CD44-positive progenitor cells. • FGF-2 increased the number of oligodendrocytes in P3 cerebellar slice culture.

  8. Induction of oligodendrocyte differentiation from adult human fibroblast-derived induced pluripotent stem cells.

    Science.gov (United States)

    Ogawa, Shin-ichiro; Tokumoto, Yasuhito; Miyake, Jun; Nagamune, Teruyuki

    2011-08-01

    Induced pluripotent stem cells (iPSCs) prepared from somatic cells might become a novel therapeutic tool in regenerative medicine, especially for the central nervous system (CNS). In this study, we attempted to induce O4-positive (O4(+)) oligodendrocytes from adult human fibroblast-derived iPSCs in vitro. We used two adult human iPSC cell lines, 201B7 and 253G1. 201B7 was induced by four-gene transduction (oct4, sox2, klf4, c-myc), and 253G1 was induced by three-gene transduction (oct4, sox2, klf4). We treated these cells with two in vitro oligodendrocyte-directed differentiation protocols that were optimized for human embryonic stem cells. One protocol used platelet-derived growth factor as the major mitogen for oligodendrocyte lineage cells, and the other protocol used epidermal growth factor (EGF) as the mitogen. Although the differentiation efficiency was low (less than 0.01%), we could induce O4(+) oligodendrocytes from 253G1 cells using the EGF-dependent differentiation protocol. This is the first report of the in vitro induction of oligodendrocytes differentiation from human iPSCs.

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

    Science.gov (United States)

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

    2016-04-01

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

  10. Oligodendrocyte differentiation from adult multipotent stem cells is modulated by glutamate.

    Science.gov (United States)

    Cavaliere, F; Urra, O; Alberdi, E; Matute, C

    2012-02-02

    We used multipotent stem cells (MSCs) derived from the young rat subventricular zone (SVZ) to study the effects of glutamate in oligodendrocyte maturation. Glutamate stimulated oligodendrocyte differentiation from SVZ-derived MSCs through the activation of specific N-methyl-D-aspartate (NMDA) receptor subunits. The effect of glutamate and NMDA on oligodendrocyte differentiation was evident in both the number of newly generated oligodendrocytes and their morphology. In addition, the levels of NMDAR1 and NMDAR2A protein increased during differentiation, whereas NMDAR2B and NMDAR3 protein levels decreased, suggesting differential expression of NMDA receptor subunits during maturation. Microfluorimetry showed that the activation of NMDA receptors during oligodendrocyte differentiation elevated cytosolic calcium levels and promoted myelination in cocultures with neurons. Moreover, we observed that stimulation of MSCs by NMDA receptors induced the generation of reactive oxygen species (ROS), which were negatively modulated by the NADPH inhibitor apocynin, and that the levels of ROS correlated with the degree of differentiation. Taken together, these findings suggest that ROS generated by NADPH oxidase by the activation of NMDA receptors promotes the maturation of oligodendrocytes and favors myelination.

  11. Cyclosporin A increases recovery after spinal cord injury but does not improve myelination by oligodendrocyte progenitor cell transplantation

    Directory of Open Access Journals (Sweden)

    Wang Feng-Chao

    2010-10-01

    Full Text Available Abstract Background Transplantation of oligodendrocyte precursor cells (OPCs is an attractive therapy for demyelinating diseases. Cyclosporin A (CsA is one of the foremost immunosuppressive agents and has widespread use in tissue and cell transplantation. However, whether CsA affects survival and differentiation of engrafted OPCs in vivo is unknown. In this study, the effect of CsA on morphological, functional and immunological aspects, as well as survival and differentiation of engrafted OPCs in injured spinal cord was explored. Results We transplanted green fluorescent protein (GFP expressed OPCs (GFP-OPCs into injured spinal cords of rats treated with or without CsA (10 mg/kg. Two weeks after cell transplantation, more GFP-positive cells were found in CsA-treated rats than that in vehicle-treated ones. However, the engrafted cells mostly differentiated into astrocytes, but not oligodendrocytes in both groups. In the CsA-treated group, a significant decrease in spinal cord lesion volume along with increase in spared myelin and neurons were found compared to the control group. Such histological improvement correlated well with an increase in behavioral recovery. Further study suggested that CsA treatment could inhibit infiltration of T cells and activation of resident microglia and/or macrophages derived from infiltrating monocytes in injured spinal cords, which contributes to the survival of engrafted OPCs and repair of spinal cord injury (SCI. Conclusions These results collectively indicate that CsA can promote the survival of engrafted OPCs in injured spinal cords, but has no effect on their differentiation. The engrafted cells mostly differentiated into astrocytes, but not oligodendrocytes. The beneficial effect of CsA on SCI and the survival of engrafted cells may be attributed to its neuroprotective effect.

  12. Oligodendrocyte Progenitor Cells Directly Utilize Lactate for Promoting Cell Cycling and Differentiation.

    Science.gov (United States)

    Ichihara, Yoshinori; Doi, Toru; Ryu, Youngjae; Nagao, Motoshi; Sawada, Yasuhiro; Ogata, Toru

    2017-05-01

    Oligodendrocyte progenitor cells (OPCs) undergo marked morphological changes to become mature oligodendrocytes, but the metabolic resources for this process have not been fully elucidated. Although lactate, a metabolic derivative of glycogen, has been reported to be consumed in oligodendrocytes as a metabolite, and to ameliorate hypomyelination induced by low glucose conditions, it is not clear about the direct contribution of lactate to cell cycling and differentiation of OPCs, and the source of lactate for remyelination. Therefore, we evaluated the effect of 1,4-dideoxy-1,4-imino-d-arabinitol (DAB), an inhibitor of the glycogen catabolic enzyme glycogen phosphorylase, in a mouse cuprizone model. Cuprizone induced demyelination in the corpus callosum and remyelination occurred after cuprizone treatment ceased. This remyelination was inhibited by the administration of DAB. To further examine whether lactate affects proliferation or differentiation of OPCs, we cultured mouse primary OPC-rich cells and analyzed the effect of lactate. Lactate rescued the slowed cell cycling induced by 0.4 mM glucose, as assessed by the BrdU-positive cell ratio. Lactate also promoted OPC differentiation detected by monitoring the mature oligodendrocyte marker myelin basic protein, in the presence of both 36.6 mM and 0.4 mM glucose. Furthermore, these lactate-mediated effects were suppressed by the reported monocarboxylate transporter inhibitor, α-cyano-4-hydroxy-cinnamate. These results suggest that lactate directly promotes the cell cycling rate and differentiation of OPCs, and that glycogen, one of the sources of lactate, contributes to remyelination in vivo. J. Cell. Physiol. 232: 986-995, 2017. © 2016 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals, Inc. © 2016 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals, Inc.

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

    Science.gov (United States)

    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.

  14. Efficient Generation of Myelinating Oligodendrocytes from Primary Progressive Multiple Sclerosis Patients by Induced Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Panagiotis Douvaras

    2014-08-01

    Full Text Available Multiple sclerosis (MS is a chronic demyelinating disease of unknown etiology that affects the CNS. While current therapies are primarily directed against the immune system, the new challenge is to address progressive MS with remyelinating and neuroprotective strategies. Here, we develop a highly reproducible protocol to efficiently derive oligodendrocyte progenitor cells (OPCs and mature oligodendrocytes from induced pluripotent stem cells (iPSCs. Key elements of our protocol include adherent cultures, dual SMAD inhibition, and addition of retinoids from the beginning of differentiation, which lead to increased yields of OLIG2 progenitors and high numbers of OPCs within 75 days. Furthermore, we show the generation of viral and integration-free iPSCs from primary progressive MS (PPMS patients and their efficient differentiation to oligodendrocytes. PPMS OPCs are functional, as demonstrated by in vivo myelination in the shiverer mouse. These results provide encouraging advances toward the development of autologous cell therapies using iPSCs.

  15. Mutation of pescadillo disrupts oligodendrocyte formation in zebrafish.

    Directory of Open Access Journals (Sweden)

    Timothy Simmons

    Full Text Available BACKGROUND: In vertebrates, the myelin sheath is essential for efficient propagation of action potentials along the axon shaft. Oligodendrocytes are the cells of the central nervous system that create myelin sheaths. During embryogenesis, ventral neural tube precursors give rise to oligodendrocyte progenitor cells, which divide and migrate throughout the central nervous system. This study aimed to investigate mechanisms that regulate oligodendrocyte progenitor cell formation. METHODOLOGY/PRINCIPAL FINDINGS: By conducting a mutagenesis screen in transgenic zebrafish, we identified a mutation, designated vu166, by an apparent reduction in the number of oligodendrocyte progenitor cells in the dorsal spinal cord. We subsequently determined that vu166 is an allele of pescadillo, a gene known to play a role in ribosome biogenesis and cell proliferation. We found that pescadillo function is required for both the proper number of oligodendrocyte progenitors to form, by regulating cell cycle progression, and for normal levels of myelin gene expression. CONCLUSIONS/SIGNIFICANCE: Our data provide evidence that neural precursors require pes function to progress through the cell cycle and produce oligodendrocyte progenitor cells and for oligodendrocyte differentiation.

  16. Fluoxetine prevents oligodendrocyte cell death by inhibiting microglia activation after spinal cord injury.

    Science.gov (United States)

    Lee, Jee Y; Kang, So R; Yune, Tae Y

    2015-05-01

    Oligodendrocyte cell death and axon demyelination after spinal cord injury (SCI) are known to be important secondary injuries contributing to permanent neurological disability. Thus, blocking oligodendrocyte cell death should be considered for therapeutic intervention after SCI. Here, we demonstrated that fluoxetine, an antidepressant drug, alleviates oligodendrocyte cell death by inhibiting microglia activation after SCI. After injury at the T9 level with a Precision Systems and Instrumentation (Lexington, KY) device, fluoxetine (10 mg/kg, intraperitoneal) was administered once a day for the indicated time points. Immunostaining with CD11b (OX-42) antibody and quantification analysis showed that microglia activation was significantly inhibited by fluoxetine at 5 days after injury. Fluoxetine also significantly inhibited activation of p38 mitogen-activated protein kinase (p38-MAPK) and expression of pro-nerve growth factor (pro-NGF), which is known to mediate oligodendrocyte cell death through the p75 neurotrophin receptor after SCI. In addition, fluoxetine attenuated activation of Ras homolog gene family member A and decreased the level of phosphorylated c-Jun and, ultimately, alleviated caspase-3 activation and significantly reduced cell death of oligodendrocytes at 5 days after SCI. Further, the decrease of myelin basic protein, myelin loss, and axon loss in white matter was also significantly blocked by fluoxetine, as compared to vehicle control. These results suggest that fluoxetine inhibits oligodendrocyte cell death by inhibiting microglia activation and p38-MAPK activation, followed by pro-NGF production after SCI, and provide a potential usage of fluoxetine for a therapeutic agent after acute SCI in humans.

  17. Effects of lipopolysaccharide on oligodendrocyte progenitor cells are mediated by astrocytes and microglia.

    Science.gov (United States)

    Pang, Y; Cai, Z; Rhodes, P G

    2000-11-15

    Oligodendrocytes are the primary cells injured in periventricular leukomalacia (PVL), a predominant form of brain white matter lesion in preterm infants. To explore the possible linkage between white matter injury and maternal infection, purified rat O-2A progenitor (Oligodendrocyte-type 2 astrocyte progenitor) cell cultures were used as a model in studying the effects of lipopolysaccharide (LPS), an endotoxin, on survival and differentiation of oligodendrocytes and the involvement of other glial cells in the effects of LPS. O-2A progenitor cells were cultured from optic nerves of 7-day-old rat pups in a chemically defined medium (CDM). Astrocyte and microglia cell cultures were prepared from the cortex of 1-day-old rat brains in the CDM. Direct treatment of LPS (1 microg/ml) to O-2A cells had no effect on viability or differentiation of these cells. When O-2A progenitor cells were cultured in the conditioned medium obtained from either astrocyte or microglial cell cultures for 48 hr, survival rate and differentiation of O-2A cells into mature oligodendrocytes were greatly enhanced as measured by the MTT assay and immunocytochemistry. The conditioned medium obtained from astrocytes or microglia treated with LPS for 48 hr, however, failed to show such a promotional effect on viability and differentiation of O-2A cells. When 5 microg/ml LPS was used to stimulate astrocytes or microglia, the conditioned medium from these glial cell cultures caused O-2A cell injury. The overall results indicate that astrocytes and microglia may promote viability and differentiation of O-2A progenitor cells under physiological conditions, but they may also mediate cytotoxic effects of LPS on oligodendrocytes under an infectious disease biochemical environment.

  18. P2X7 receptors and Fyn kinase mediate ATP-induced oligodendrocyte progenitor cell migration.

    Science.gov (United States)

    Feng, Ji-Feng; Gao, Xiao-Fei; Pu, Ying-Yan; Burnstock, Geoffrey; Xiang, Zhenghua; He, Cheng

    2015-09-01

    Recruitment of oligodendrocyte precursor cells (OPCs) to the lesions is the most important event for remyelination after central nervous system (CNS) injury or in demyelinating diseases. However, the underlying molecular mechanism is not fully understood. In the present study, we found high concentrations of ATP could increase the number of migrating OPCs in vitro, while after pretreatment with oxidized ATP (a P2X7 receptor antagonist), the promotive effect was attenuated. The promotive effect of 2'(3')-O-(4-benzoylbenzoyl) adenosine 5'-triphosphate (BzATP) (a P2X7 receptor agonist) was more potent than ATP. After incubation with BzATP, the activity of Fyn, one member of the Src family of kinases, was enhanced. Moreover, the interaction between P2X7 and Fyn was identified by co-immunoprecipitation. After blocking the activity of Fyn or down-regulating the expression of Fyn, the migration of OPCs induced by BzATP was inhibited. These data indicate that P2X7 receptors/Fyn may mediate ATP-induced OPC migration under pathological conditions.

  19. PPARγ agonists promote oligodendrocyte differentiation of neural stem cells by modulating stemness and differentiation genes.

    Directory of Open Access Journals (Sweden)

    Saravanan Kanakasabai

    Full Text Available Neural stem cells (NSCs are a small population of resident cells that can grow, migrate and differentiate into neuro-glial cells in the central nervous system (CNS. Peroxisome proliferator-activated receptor gamma (PPARγ is a nuclear receptor transcription factor that regulates cell growth and differentiation. In this study we analyzed the influence of PPARγ agonists on neural stem cell growth and differentiation in culture. We found that in vitro culture of mouse NSCs in neurobasal medium with B27 in the presence of epidermal growth factor (EGF and basic fibroblast growth factor (bFGF induced their growth and expansion as neurospheres. Addition of all-trans retinoic acid (ATRA and PPARγ agonist ciglitazone or 15-Deoxy-Δ(12,14-Prostaglandin J(2 (15d-PGJ2 resulted in a dose-dependent inhibition of cell viability and proliferation of NSCs in culture. Interestingly, NSCs cultured with PPARγ agonists, but not ATRA, showed significant increase in oligodendrocyte precursor-specific O4 and NG2 reactivity with a reduction in NSC marker nestin, in 3-7 days. In vitro treatment with PPARγ agonists and ATRA also induced modest increase in the expression of neuronal β-III tubulin and astrocyte-specific GFAP in NSCs in 3-7 days. Further analyses showed that PPARγ agonists and ATRA induced significant alterations in the expression of many stemness and differentiation genes associated with neuro-glial differentiation in NSCs. These findings highlight the influence of PPARγ agonists in promoting neuro-glial differentiation of NSCs and its significance in the treatment of neurodegenerative diseases.

  20. Exploration of protective strategies against oligodendrocyte cell death in Krabbe disease models

    Directory of Open Access Journals (Sweden)

    Gonzalo Arboleda

    2015-02-01

    Full Text Available Krabbe disease (KD patients accumulate psychosine (galactosylsphingosine, a cytotoxic metabolite for oligodendrocytes, inducing early demyelination. Apoptosis has been suggested that plays an important role in psychosine-induced oligodendrocytes cell death in culture and in brains of Krabbe patients and an animal model of the disease (twitcher mouse. However, the molecular mechanism that triggers the activation of the apoptotic pathway, and hence the development/progression of the disease, still is not well understood. Here we report that silencing GALC gene expression induces cell death of the human derived oligodendrocyte cell line MO3.13. The induction of cell death is associated with the activation of caspase 3 and increase in Bax expression, suggesting that mitochondria is compromise, and decrease in cell survival signaling pathways such as PI3K/AKT, MAPK/ERK and AMPK, as observed by western blot analysis, 2 days after silencing. The data suggests an important psychosine-induced deregulation in apoptotic and anti-apoptotic cellular pathways. Moreover, pre-treatment with insuline-like growth factor (IGF-1 and PPARalfa agonist (WY 14643, significantly provides protection against the psychosine-induced changes described. Our data indicates that oligodendrocytes have a marked susceptibility to endogenous accumulation of psychosine and identified potential compounds that may offer protection against psychosine-induced apoptosis in vivo.

  1. Differential and cell development-dependent localization of myelin mRNAs in oligodendrocytes

    NARCIS (Netherlands)

    deVries, H; deJonge, JC; Schrage, C; vanderHaar, ME; Hoekstra, D

    1997-01-01

    In oligodendrocytes (OLG), the mRNAs for the various myelin proteins localize to different intracellular sites, Whereas the confinement of myelin basic protein (MBP) mRNA to the processes of the cell has been well established, we demonstrate that most other myelin mRNA species are mainly present in

  2. DISC1 (disrupted-in-schizophrenia-1 regulates differentiation of oligodendrocytes.

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Hattori

    Full Text Available Disrupted-in-schizophrenia 1 (DISC1 is a gene disrupted by a translocation, t(1;11 (q42.1;q14.3, that segregates with major psychiatric disorders, including schizophrenia, recurrent major depression and bipolar affective disorder, in a Scottish family. Here we report that mammalian DISC1 endogenously expressed in oligodendroglial lineage cells negatively regulates differentiation of oligodendrocyte precursor cells into oligodendrocytes. DISC1 expression was detected in oligodendrocytes of the mouse corpus callosum at P14 and P70. DISC1 mRNA was expressed in primary cultured rat cortical oligodendrocyte precursor cells and decreased when oligodendrocyte precursor cells were induced to differentiate by PDGF deprivation. Immunocytochemical analysis showed that overexpressed DISC1 was localized in the cell bodies and processes of oligodendrocyte precursor cells and oligodendrocytes. We show that expression of the myelin related markers, CNPase and MBP, as well as the number of cells with a matured oligodendrocyte morphology, were decreased following full length DISC1 overexpression. Conversely, both expression of CNPase and the number of oligodendrocytes with a mature morphology were increased following knockdown of endogenous DISC1 by RNA interference. Overexpression of a truncated form of DISC1 also resulted in an increase in expression of myelin related proteins and the number of mature oligodendrocytes, potentially acting via a dominant negative mechanism. We also identified involvement of Sox10 and Nkx2.2 in the DISC1 regulatory pathway of oligodendrocyte differentiation, both well-known transcription factors involved in the regulation of myelin genes.

  3. Cytolysis of oligodendrocytes is mediated by killer (K) cells but not by natural killer (NK) cells.

    Science.gov (United States)

    Satoh, J; Kim, S U; Kastrukoff, L F

    1991-03-01

    The cytotoxic activity of killer (K) cells against enriched cultures of bovine oligodendrocytes (BOL) was investigated in multiple sclerosis (MS) and controls. Human K cells mediated cytotoxicity to primary cultures of BOL in the presence of anti-BOL antiserum in all study groups, while BOL were resistant to human natural killer (NK) cells. Cytotoxic activity was significantly reduced in MS when compared to age-matched normal controls but not when compared to other neurologic disease (OND) patients. K cell-mediated lysis of BOL could also be induced with anti-galactocerebroside antibody but not with other antibodies including those specific for OL antigens (myelin basic protein, proteolipid apoprotein, and 2',3'-cyclic nucleotide 3'-phosphodiesterase). Enrichment of the effector population indicated that antibody-dependent cell-mediated cytotoxicity (ADCC) to BOL was mediated by large granular lymphocytes, and the effector population was further characterized by flow cytometry. The effector cells mediating ADCC could be inhibited by protein A of Staphylococcus aureus, and by K562 cells in cold competition assay. These observations indicate that oligodendrocytes are resistant to NK cells but are susceptible to cytolysis mediated by K cells. This may represent a potentially important immune mechanism in the pathogenesis of MS.

  4. The oligodendrocyte-specific G protein-coupled receptor GPR17 is a cell-intrinsic timer of myelination.

    Science.gov (United States)

    Chen, Ying; Wu, Heng; Wang, Shuzong; Koito, Hisami; Li, Jianrong; Ye, Feng; Hoang, Jenny; Escobar, Sabine S; Gow, Alexander; Arnett, Heather A; Trapp, Bruce D; Karandikar, Nitin J; Hsieh, Jenny; Lu, Q Richard

    2009-11-01

    The basic helix-loop-helix transcription factor Olig1 promotes oligodendrocyte maturation and is required for myelin repair. We characterized an Olig1-regulated G protein-coupled receptor, GPR17, whose function is to oppose the action of Olig1. Gpr17 was restricted to oligodendrocyte lineage cells, but was downregulated during the peak period of myelination and in adulthood. Transgenic mice with sustained Gpr17 expression in oligodendrocytes exhibited stereotypic features of myelinating disorders in the CNS. Gpr17 overexpression inhibited oligodendrocyte differentiation and maturation both in vivo and in vitro. Conversely, Gpr17 knockout mice showed early onset of oligodendrocyte myelination. The opposing action of Gpr17 on oligodendrocyte maturation reflects, at least partially, upregulation and nuclear translocation of the potent oligodendrocyte differentiation inhibitors ID2/4. Collectively, these findings suggest that GPR17 orchestrates the transition between immature and myelinating oligodendrocytes via an ID protein-mediated negative regulation and may serve as a potential therapeutic target for CNS myelin repair.

  5. Cutting edge: Multiple sclerosis-like lesions induced by effector CD8 T cells recognizing a sequestered antigen on oligodendrocytes.

    Science.gov (United States)

    Saxena, Amit; Bauer, Jan; Scheikl, Tanja; Zappulla, Jacques; Audebert, Marc; Desbois, Sabine; Waisman, Ari; Lassmann, Hans; Liblau, Roland S; Mars, Lennart T

    2008-08-01

    CD8 T cells are emerging as important players in multiple sclerosis (MS) pathogenesis, although their direct contribution to tissue damage is still debated. To assess whether autoreactive CD8 T cells can contribute to the pronounced loss of oligodendrocytes observed in MS plaques, we generated mice in which the model Ag influenza hemagglutinin is selectively expressed in oligodendrocytes. Transfer of preactivated hemagglutinin-specific CD8 T cells led to inflammatory lesions in the optic nerve, spinal cord, and brain. These lesions, associating CD8 T cell infiltration with focal loss of oligodendrocytes, demyelination, and microglia activation, were very reminiscent of active MS lesions. Thus, our study demonstrates the potential of CD8 T cells to induce oligodendrocyte lysis in vivo as a likely consequence of direct Ag-recognition. These results provide new insights with regard to CNS tissue damage mediated by CD8 T cells and for understanding the role of CD8 T cells in MS.

  6. Systematic review of the pharmacological properties of oligodendrocyte lineage

    Directory of Open Access Journals (Sweden)

    Carla eMarinelli

    2016-02-01

    Full Text Available OOligodendrogenesis and oligodendrocyte precursor maturation are essential processes during the course of central nervous system development, and lead to the myelination of axons. Cells of the oligodendrocyte lineage are generated in the germinal zone from migratory bipolar oligodendrocyte precursor cells, and acquire cell surface markers as they mature and respond specifically to factors which regulate proliferation, migration, differentiation, and survival. Loss of myelin underlies a wide range of neurological disorders, some of an autoimmune nature – multiple sclerosis probably being the most prominent. Current therapies are based on the use of immunomodulatory agents which are likely to promote myelin repair (remyelination indirectly by subverting the inflammatory response, aspects of which impair the differentiation of oligodendrocyte precursor cells. Cells of the oligodendrocyte lineage express and are capable of responding to a diverse array of ligand-receptor pairs, including neurotransmitters and nuclear receptors such as gamma-aminobutyric acid, glutamate, ATP, serotonin, acetylcholine, nitric oxide, opioids, prostaglandins, prolactin, cannabinoids and nuclear receptors. The intent of this review is to provide the reader with a synopsis of our present state of knowledge concerning the pharmacological properties of the oligodendrocyte lineage, with particular attention to these receptor-ligand (i.e., neurotransmitters and nuclear receptor interactions that can influence oligodendrocyte migration, proliferation, differentiation, and myelination, and an appraisal of their therapeutic potential. For example, many promising mediators work through Ca2+ signalling, and the balance between Ca2+ influx and efflux can determine the temporal and spatial properties of oligodendrocytes. Moreover, Ca2+ signalling in oligodendrocyte precursor cells can influence not only differentiation and myelination, but also process extension and migration, as

  7. Deletion of Jun proteins in adult oligodendrocytes does not perturb cell survival, or myelin maintenance in vivo.

    Directory of Open Access Journals (Sweden)

    Bettina Schreiner

    Full Text Available Oligodendrocytes, the myelin-forming glial cells of the central nervous system (CNS, are fundamental players in rapid impulse conduction and normal axonal functions. JunB and c-Jun are DNA-binding components of the AP-1 transcription factor, which is known to regulate different processes such as proliferation, differentiation, stress responses and death in several cell types, including cultured oligodendrocyte/lineage cells. By selectively inactivating Jun B and c-Jun in myelinating oligodendrocytes in vivo, we generated mutant mice that developed normally, and within more than 12 months showed normal ageing and survival rates. In the adult CNS, absence of JunB and c-Jun from mature oligodendrocytes caused low-grade glial activation without overt signs of demyelination or secondary leukocyte infiltration into the brain. Even after exposure to toxic or autoimmune oligodendrocyte insults, signs of altered oligodendrocyte viability were mild and detectable only upon cuprizone treatment. We conclude that JunB and c-Jun expression in post-mitotic oligodendrocytes is mostly dispensable for the maintainance of white matter tracts throughout adult life, even under demyelinating conditions.

  8. Beta4 tubulin identifies a primitive cell source for oligodendrocytes in the mammalian brain.

    Science.gov (United States)

    Wu, Chuanshen; Chang, Ansi; Smith, Maria C; Won, Roy; Yin, Xinghua; Staugaitis, Susan M; Agamanolis, Dimitri; Kidd, Grahame J; Miller, Robert H; Trapp, Bruce D

    2009-06-17

    We have identified a novel population of cells in the subventricular zone (SVZ) of the mammalian brain that expresses beta4 tubulin (betaT4) and has properties of primitive neuroectodermal cells. betaT4 cells are scattered throughout the SVZ of the lateral ventricles in adult human brain and are significantly increased in the SVZs bordering demyelinated white matter in multiple sclerosis brains. In human fetal brain, betaT4 cell densities peak during the latter stages of gliogenesis, which occurs in the SVZ of the lateral ventricles. betaT4 cells represent 95% of cells in neurospheres treated with the anti-mitotic agent Ara C. betaT4 cells produce oligodendrocytes, neurons, and astrocytes in vitro. We compared the myelinating potential of betaT4-positive cells with A2B5-positive oligodendrocyte progenitor cells after transplantation (25,000 cells) into postnatal day 3 (P3) myelin-deficient rat brains. At P20, the progeny of betaT4 cells myelinated up to 4 mm of the external capsule, which significantly exceeded that of transplanted A2B5-positive progenitor cells. Such extensive and rapid mature CNS cell generation by a relatively small number of transplanted cells provides in vivo support for the therapeutic potential of betaT4 cells. We propose that betaT4 cells are an endogenous cell source that can be recruited to promote neural repair in the adult telencephalon.

  9. NMDA modulates oligodendrocyte differentiation of subventricular zone cells through PKC activation

    Directory of Open Access Journals (Sweden)

    Fabio eCavaliere

    2013-12-01

    Full Text Available Multipotent cells from the juvenile subventricular zone (SVZ possess the ability to differentiate into new neural cells. Depending on local signals, SVZ can generate new neurons, astrocytes or oligodendrocytes. We previously demonstrated that activation of NMDA receptors in SVZ progenitors increases the rate of oligodendrocyte differentiation. Here we investigated the mechanisms involved in NMDA receptor-dependent differentiation. Using functional studies performed with the reporter gene luciferase we found that activation of NMDA receptor stimulates PKC. In turn, stimulation of PKC precedes the activation of NADPH oxidase (NOX as demonstrated by translocation of the p67phox subunit to the cellular membrane. We propose that NOX2 is involved in the transduction of the signal from NMDA receptors through PKC activation as the inhibitor gp91 reduced their pro-differentiation effect. In addition, our data and that from other groups suggest that signaling through the NMDA receptor/PKC/NOX2 cascade generates ROS that activate the PI3/mTOR pathway and finally leads to the generation of new oligodendrocytes.

  10. K(V7/KCNQ channels are functionally expressed in oligodendrocyte progenitor cells.

    Directory of Open Access Journals (Sweden)

    Wei Wang

    Full Text Available BACKGROUND: K(V7/KCNQ channels are widely expressed in neurons and they have multiple important functions, including control of excitability, spike afterpotentials, adaptation, and theta resonance. Mutations in KCNQ genes have been demonstrated to associate with human neurological pathologies. However, little is known about whether K(V7/KCNQ channels are expressed in oligodendrocyte lineage cells (OLCs and what their functions in OLCs. METHODS AND FINDINGS: In this study, we characterized K(V7/KCNQ channels expression in rat primary cultured OLCs by RT-PCR, immunostaining and electrophysiology. KCNQ2-5 mRNAs existed in all three developmental stages of rat primary cultured OLCs. K(V7/KCNQ proteins were also detected in oligodendrocyte progenitor cells (OPCs, early developmental stages of OLCs of rat primary cultures and cortex slices. Voltage-clamp recording revealed that the I(M antagonist XE991 significantly reduced K(V7/KCNQ channel current (I(K(Q in OPCs but not in differentiated oligodendrocytes. In addition, inhibition of K(V7/KCNQ channels promoted OPCs motility in vitro. CONCLUSIONS: These findings showed that K(V7/KCNQ channels were functionally expressed in rat primary cultured OLCs and might play an important role in OPCs functioning in physiological or pathological conditions.

  11. Oligodendrocytes in a nutshell

    Directory of Open Access Journals (Sweden)

    John-Paul eMichalski

    2015-09-01

    Full Text Available Oligodendrocytes are the myelinating cells of the central nervous system (CNS. While the phrase is oft repeated and holds true, the last few years have borne witness to radical change in our understanding of this unique cell type. Once considered static glue, oligodendrocytes are now seen as plastic and adaptive, capable of reacting to a changing CNS. This review is intended as a primer and guide, exploring how the past five years have fundamentally altered our appreciation of oligodendrocyte development and CNS myelination.

  12. Oligodendrocytes in a Nutshell.

    Science.gov (United States)

    Michalski, John-Paul; Kothary, Rashmi

    2015-01-01

    Oligodendrocytes are the myelinating cells of the central nervous system (CNS). While the phrase is oft repeated and holds true, the last few years have borne witness to radical change in our understanding of this unique cell type. Once considered static glue, oligodendrocytes are now seen as plastic and adaptive, capable of reacting to a changing CNS. This review is intended as a primer and guide, exploring how the past 5 years have fundamentally altered our appreciation of oligodendrocyte development and CNS myelination.

  13. Treatment with metallothionein prevents demyelination and axonal damage and increases oligodendrocyte precursors and tissue repair during experimental autoimmune encephalomyelitis

    DEFF Research Database (Denmark)

    Penkowa, Milena; Hidalgo, Juan

    2003-01-01

    )beta, neurotrophin-3 (NT-3), NT-4/5, and nerve growth factor (NGF). These beneficial effects of Zn-MT-II treatment could not be attributable to its zinc content per se. The present results support further the use of Zn-MT-II as a safe and successful therapy for multiple sclerosis....... for the first time that Zn-MT-II treatment during EAE significantly prevents demyelination and axonal damage and transection, and stimulates oligodendroglial regeneration from precursor cells, as well as the expression of the growth factors basic fibroblast growth factor (bFGF), transforming growth factor (TGF...

  14. The Innate Lymphoid Cell Precursor.

    Science.gov (United States)

    Ishizuka, Isabel E; Constantinides, Michael G; Gudjonson, Herman; Bendelac, Albert

    2016-05-20

    The discovery of tissue-resident innate lymphoid cell populations effecting different forms of type 1, 2, and 3 immunity; tissue repair; and immune regulation has transformed our understanding of mucosal immunity and allergy. The emerging complexity of these populations along with compounding issues of redundancy and plasticity raise intriguing questions about their precise lineage relationship. Here we review advances in mapping the emergence of these lineages from early lymphoid precursors. We discuss the identification of a common innate lymphoid cell precursor characterized by transient expression of the transcription factor PLZF, and the lineage relationships of innate lymphoid cells with conventional natural killer cells and lymphoid tissue inducer cells. We also review the rapidly growing understanding of the network of transcription factors that direct the development of these lineages.

  15. Differentiation of Induced Pluripotent Stem Cells Into Functional Oligodendrocytes

    NARCIS (Netherlands)

    Czepiel, Marcin; Balasubramaniyan, Veerakumar; Schaafsma, Wandert; Stancic, Mirjana; Mikkers, Harald; Huisman, Christian; Boddeke, Erik; Copray, Sjef

    2011-01-01

    The technology to generate autologous pluripotent stem cells (iPS cells) from almost any somatic cell type has brought various cell replacement therapies within clinical research. Besides the challenge to optimize iPS protocols to appropriate safety and GMP levels, procedures need to be developed to

  16. Golli myelin basic proteins stimulate oligodendrocyte progenitor cell proliferation and differentiation in remyelinating adult mouse brain.

    Science.gov (United States)

    Paez, Pablo M; Cheli, Veronica T; Ghiani, Cristina A; Spreuer, Vilma; Handley, Vance W; Campagnoni, Anthony T

    2012-07-01

    Golli myelin basic proteins are necessary for normal myelination, acting via voltage and store-dependent Ca(2+) entry at multiple steps during oligodendrocyte progenitor cell (OPC) development. To date nothing is known regarding the role of golli proteins in demyelination or remyelination events. Here the effects of golli ablation and overexpression in myelin loss and recovery were examined using the cuprizone (CPZ) model of demyelination/remyelination. We found severe demyelination in the corpus callosum (CC) of golli-overexpressing mice (JOE) during the CPZ treatment, which was accompanied by an increased number of reactive astrocytes and activation of microglia/macrophages. During demyelination of JOE brains, a significant increase in the number of proliferating OPCs was found in the CC as well as in the subventricular zone, and our data indicate that these progenitors matured and fully remyelinated the CC of JOE animals after CPZ withdrawal. In contrast, in the absence of golli (golli-KO mice) delayed myelin loss associated with a smaller immune response, and a lower number of OPCs was found in these mice during the CPZ treatment. Furthermore, incomplete remyelination was observed after CPZ removal in large areas of the CC of golli-KO mice, reflecting irregular recovery of the oligodendrocyte population and subsequent myelin sheath formation. Our findings demonstrate that golli proteins sensitize mature oligodendrocytes to CPZ-induced demyelination, while at the same time stimulate the proliferation/recruitment of OPCs during demyelination, resulting in accelerated remyelination.

  17. Axonal degeneration stimulates the formation of NG2+ cells and oligodendrocytes in the mouse

    DEFF Research Database (Denmark)

    Nielsen, Helle Hvilsted; Ladeby, Rune; Drøjdahl, Nina

    2006-01-01

    the response of the NG2+ cells to the different components of demyelinating pathology, we investigated the response of adult NG2+ cells to axonal degeneration in the absence of primary myelin or oligodendrocyte pathology. Axonal degeneration was induced in the hippocampal dentate gyrus of adult mice...... by transection of the entorhino-dentate perforant path projection. The acutely induced degeneration of axons and terminals resulted in a prompt response of NG2+ cells, consisting of morphological transformation, cellular proliferation, and upregulation of NG2 expression days 2-3 after surgery. This was followed...

  18. Neural precursors derived from human embryonic stem cells

    Institute of Scientific and Technical Information of China (English)

    Peng Hongmei; Chen Gui'an

    2005-01-01

    Human embryonic stem (hES) cells provide a promising supply of specific cell types for transplantation therapy. We presented here the method to induce differentiation of purified neural precursors from hES cells, hES cells (Line PKU-1 and Line PKU-2) were cultured in suspension in bacteriological Petri dishes, which differentiated into cystic embryoid bodies (EBs).The EBs were then cultured in N2 medium containing bFGF in poly- L-lysine-coated tissue culture dishes for two weeks. The central, small cells with 2-3 short processes of the spreading outgrowth were isolated mechanically and replated. The resulting neurospheres were cultured in suspension for 10 days, then dissociated into single cell suspension with a Pasteur pipette and plated. Cells grew vigorously in an attached way and were passed every 4-5 days. Almost all the cells were proved nestin positive by immunostaining. Following withdrawal of bFGF, they differentiated into neurons expressing β-tubulin isotypeⅢ, GABA, serotonin and synaptophysin.Through induction of PDGF-AA, they differentiated into astrocytes expressing GFAP and oligodendrocytes expressing O4. The results showed that hES cells can differentiate into typical neural precursors expressing the specific marker nestin and capable of generating all three cell types of the central nervous system (CNS) in vitro.

  19. Effects of neurotrophin-3 on the differentiation of neural stem cells into neurons and oligodendrocytes

    Institute of Scientific and Technical Information of China (English)

    Guowei Zhu; Chongran Sun; Weiguo Liu

    2012-01-01

    In this study,cells from the cerebral cortex of fetal rats at pregnant 16 days were harvested and cultured with 20 μg/L neurotrophin-3.After 7 days of culture,immunocytochemical staining showed that,22.4% of cells were positive for nestin,10.5% were positive for β-Ⅲ tubulin (neuronal marker),and 60.6% were positive for glial fibrillary acidic protein,but no cells were positive for O4 (oligodendrocytic marker).At 14 days,there were 5.6% nestin-,9.6% β-Ⅲ tubulin-,81.1% glial fibrillary acidic protein-,and 2.2% O4-positive cells.In cells not treated with neurotrophin-3,some were nestin-positive,while the majority showed positive staining for glial fibrillary acidic protein.Our experimental findings indicate that neurotrophin-3 is a crucial factor for inducing neural stem cells differentiation into neurons and oligodendrocytes.

  20. Calcium receptor expression and function in oligodendrocyte commitment and lineage progression: potential impact on reduced myelin basic protein in CaR-null mice

    DEFF Research Database (Denmark)

    Chattopadhyay, N.; Espinosa-Jeffrey, A.; Yano, S.

    2008-01-01

    Oligodendrocytes develop from oligodendrocyte progenitor cells (OPCs), which in turn arise from a subset of neuroepithelial precursor cells during midneurogenesis. Development of the oligodendrocyte lineage involves a plethora of cell-intrinsic and -extrinsic signals. A cell surface calcium......-sensing receptor (CaR) has been shown to be functionally expressed in immature oligodendrocytes. Here, we investigated the expression and function of the CaR during oligodendrocyte development. We show that the order of CaR mRNA expression as assessed by quantitative polymerase chain reaction is mature...... oligodendrocyte > neuron > astrocyte. We next determined the rank order of CaR expression on inducing specification of neural stem cells to the neuronal, oligodendroglial, or astrocytic lineages and found that the relative levels of CaR mRNA expression are OPC > neuron > astrocytes. CaR mRNA expression in cells...

  1. Systematic Review of Pharmacological Properties of the Oligodendrocyte Lineage.

    Science.gov (United States)

    Marinelli, Carla; Bertalot, Thomas; Zusso, Morena; Skaper, Stephen D; Giusti, Pietro

    2016-01-01

    Oligodendrogenesis and oligodendrocyte precursor maturation are essential processes during the course of central nervous system development, and lead to the myelination of axons. Cells of the oligodendrocyte lineage are generated in the germinal zone from migratory bipolar oligodendrocyte precursor cells (OPCs), and acquire cell surface markers as they mature and respond specifically to factors which regulate proliferation, migration, differentiation, and survival. Loss of myelin underlies a wide range of neurological disorders, some of an autoimmune nature-multiple sclerosis probably being the most prominent. Current therapies are based on the use of immunomodulatory agents which are likely to promote myelin repair (remyelination) indirectly by subverting the inflammatory response, aspects of which impair the differentiation of OPCs. Cells of the oligodendrocyte lineage express and are capable of responding to a diverse array of ligand-receptor pairs, including neurotransmitters and nuclear receptors such as γ-aminobutyric acid, glutamate, adenosine triphosphate, serotonin, acetylcholine, nitric oxide, opioids, prostaglandins, prolactin, and cannabinoids. The intent of this review is to provide the reader with a synopsis of our present state of knowledge concerning the pharmacological properties of the oligodendrocyte lineage, with particular attention to these receptor-ligand (i.e., neurotransmitters and nuclear receptor) interactions that can influence oligodendrocyte migration, proliferation, differentiation, and myelination, and an appraisal of their therapeutic potential. For example, many promising mediators work through Ca(2+) signaling, and the balance between Ca(2+) influx and efflux can determine the temporal and spatial properties of oligodendrocytes (OLs). Moreover, Ca(2+) signaling in OPCs can influence not only differentiation and myelination, but also process extension and migration, as well as cell death in mature mouse OLs. There is also evidence

  2. Electric Signals Regulate the Directional Migration of Oligodendrocyte Progenitor Cells (OPCs) via β1 Integrin.

    Science.gov (United States)

    Zhu, Bangfu; Nicholls, Matthew; Gu, Yu; Zhang, Gaofeng; Zhao, Chao; Franklin, Robin J M; Song, Bing

    2016-11-22

    The guided migration of neural cells is essential for repair in the central nervous system (CNS). Oligodendrocyte progenitor cells (OPCs) will normally migrate towards an injury site to re-sheath demyelinated axons; however the mechanisms underlying this process are not well understood. Endogenous electric fields (EFs) are known to influence cell migration in vivo, and have been utilised in this study to direct the migration of OPCs isolated from neonatal Sprague-Dawley rats. The OPCs were exposed to physiological levels of electrical stimulation, and displayed a marked electrotactic response that was dependent on β1 integrin, one of the key subunits of integrin receptors. We also observed that F-actin, an important component of the cytoskeleton, was re-distributed towards the leading edge of the migrating cells, and that this asymmetric rearrangement was associated with β1 integrin function.

  3. MicroRNA expression profiling of oligodendrocyte differentiation from human embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Brian S Letzen

    Full Text Available BACKGROUND: Cells of the oligodendrocyte (OL lineage play a vital role in the production and maintenance of myelin, a multilamellar membrane which allows for saltatory conduction along axons. These cells may provide immense therapeutic potential for lost sensory and motor function in demyelinating conditions, such as spinal cord injury, multiple sclerosis, and transverse myelitis. However, the molecular mechanisms controlling OL differentiation are largely unknown. MicroRNAs (miRNAs are considered the "micromanagers" of gene expression with suggestive roles in cellular differentiation and maintenance. Although unique patterns of miRNA expression in various cell lineages have been characterized, this is the first report documenting their expression during oligodendrocyte maturation from human embryonic stem (hES cells. Here, we performed a global miRNA analysis to reveal and identify characteristic patterns in the multiple stages leading to OL maturation from hES cells including those targeting factors involved in myelin production. METHODOLOGY/PRINCIPAL FINDINGS: We isolated cells from 8 stages of OL differentiation. Total RNA was subjected to miRNA profiling and validations preformed using real-time qRT-PCR. A comparison of miRNAs from our cultured OLs and OL progenitors showed significant similarities with published results from equivalent cells found in the rat and mouse central nervous system. Principal component analysis revealed four main clusters of miRNA expression corresponding to early, mid, and late progenitors, and mature OLs. These results were supported by correlation analyses between adjacent stages. Interestingly, the highest differentially-expressed miRNAs demonstrated a similar pattern of expression throughout all stages of differentiation, suggesting that they potentially regulate a common target or set of targets in this process. The predicted targets of these miRNAs include those with known or suspected roles in

  4. Cannabidiol protects oligodendrocyte progenitor cells from inflammation-induced apoptosis by attenuating endoplasmic reticulum stress.

    Science.gov (United States)

    Mecha, M; Torrao, A S; Mestre, L; Carrillo-Salinas, F J; Mechoulam, R; Guaza, C

    2012-06-28

    Cannabidiol (CBD) is the most abundant cannabinoid in Cannabis sativa that has no psychoactive properties. CBD has been approved to treat inflammation, pain and spasticity associated with multiple sclerosis (MS), of which demyelination and oligodendrocyte loss are hallmarks. Thus, we investigated the protective effects of CBD against the damage to oligodendrocyte progenitor cells (OPCs) mediated by the immune system. Doses of 1 μM CBD protect OPCs from oxidative stress by decreasing the production of reactive oxygen species. CBD also protects OPCs from apoptosis induced by LPS/IFNγ through the decrease of caspase 3 induction via mechanisms that do not involve CB1, CB2, TRPV1 or PPARγ receptors. Tunicamycin-induced OPC death was attenuated by CBD, suggesting a role of endoplasmic reticulum (ER) stress in the mode of action of CBD. This protection against ER stress-induced apoptosis was associated with reduced phosphorylation of eiF2α, one of the initiators of the ER stress pathway. Indeed, CBD diminished the phosphorylation of PKR and eiF2α induced by LPS/IFNγ. The pro-survival effects of CBD in OPCs were accompanied by decreases in the expression of ER apoptotic effectors (CHOP, Bax and caspase 12), and increased expression of the anti-apoptotic Bcl-2. These findings suggest that attenuation of the ER stress pathway is involved in the 'oligoprotective' effects of CBD during inflammation.

  5. Erk1/2 but not PI3K pathway is required for neurotrophin 3-induced oligodendrocyte differentiation of post-natal neural stem cells

    Institute of Scientific and Technical Information of China (English)

    XinhuaHu; LuJin; LinyinFeng

    2005-01-01

    Neurotrophin 3 (NT3) induces mouse cortical stem cells to an asymmetric division from a symmetric division, suggesting that NT3 may work as an early differentiative signal for neural stem cells (NSCs). Here, using cultured post-natal hippocampal stem cells as a model, we demonstrated that NT3-stimulation causes NSCs to differentiate into oligodendrocyte precursors (OLPs) through an extracellular signal-related kinasel/2 (Erkl/2)-dependent pathway. Following the treatment of NT3 for 24h, NSCs differentiated into more OLPs and fewer neurons, whereas the proliferation and survival of OLPs were not affected. NT3 induced a series of intracellular responses including enhancement of phosphorylation of Erk 1/2 or Akt and increase of expression of oligodendrocyte lineage gene (Olig)-1, a transcriptional factor known to participate in oligodendrocyte development. Application of U0126, a specific inhibitor of MEK1/2 which are upstream to Erk1/2, blocked the phosphorylation of Erk1/2, suppressed the expression of Olig-1 and prevented NSC differentiation into OLPs in response to NT3 stimulation. Blockade of TrkC also inhibited the differentiation of NSCs to OLPs induced by NT3. However,administration of LY294002, an inhibitor of phosphatidylinositol 3 kinase (PI3K), blocked the phosphorylation of Akt but did not affect the effect of NT3 on the expression of Olig-1 and on NSC differentiation into OLPs. Taken together, these results suggest that NT3 induce NSCs to differentiate into OLPs by enhancing the expression of Olig-1 through an Erk1/2-dependent pathway.

  6. Convergent functional genomics of oligodendrocyte differentiation identifies multiple autoinhibitory signaling circuits.

    Science.gov (United States)

    Gobert, Rosanna Pescini; Joubert, Lara; Curchod, Marie-Laure; Salvat, Catherine; Foucault, Isabelle; Jorand-Lebrun, Catherine; Lamarine, Marc; Peixoto, Hélène; Vignaud, Chloé; Frémaux, Christèle; Jomotte, Thérèse; Françon, Bernard; Alliod, Chantal; Bernasconi, Lilia; Abderrahim, Hadi; Perrin, Dominique; Bombrun, Agnes; Zanoguera, Francisca; Rommel, Christian; Hooft van Huijsduijnen, Rob

    2009-03-01

    Inadequate remyelination of brain white matter lesions has been associated with a failure of oligodendrocyte precursors to differentiate into mature, myelin-producing cells. In order to better understand which genes play a critical role in oligodendrocyte differentiation, we performed time-dependent, genome-wide gene expression studies of mouse Oli-neu cells as they differentiate into process-forming and myelin basic protein-producing cells, following treatment with three different agents. Our data indicate that different inducers activate distinct pathways that ultimately converge into the completely differentiated state, where regulated gene sets overlap maximally. In order to also gain insight into the functional role of genes that are regulated in this process, we silenced 88 of these genes using small interfering RNA and identified multiple repressors of spontaneous differentiation of Oli-neu, most of which were confirmed in rat primary oligodendrocyte precursors cells. Among these repressors were CNP, a well-known myelin constituent, and three phosphatases, each known to negatively control mitogen-activated protein kinase cascades. We show that a novel inhibitor for one of the identified genes, dual-specificity phosphatase DUSP10/MKP5, was also capable of inducing oligodendrocyte differentiation in primary oligodendrocyte precursors. Oligodendrocytic differentiation feedback loops may therefore yield pharmacological targets to treat disease related to dysfunctional myelin deposition.

  7. Early loss of oligodendrocytes in human and experimental neuromyelitis optica lesions.

    Science.gov (United States)

    Wrzos, Claudia; Winkler, Anne; Metz, Imke; Kayser, Dieter M; Thal, Dietmar R; Wegner, Christiane; Brück, Wolfgang; Nessler, Stefan; Bennett, Jeffrey L; Stadelmann, Christine

    2014-04-01

    Neuromyelitis optica (NMO) is a chronic, mostly relapsing inflammatory demyelinating disease of the CNS characterized by serum anti-aquaporin 4 (AQP4) antibodies in the majority of patients. Anti-AQP4 antibodies derived from NMO patients target and deplete astrocytes in experimental models when co-injected with complement. However, the time course and mechanisms of oligodendrocyte loss and demyelination and the fate of oligodendrocyte precursor cells (OPC) have not been examined in detail. Also, no studies regarding astrocyte repopulation of experimental NMO lesions have been reported. We utilized two rat models using either systemic transfer or focal intracerebral injection of recombinant human anti-AQP4 antibodies to generate NMO-like lesions. Time-course experiments were performed to examine oligodendroglial and astroglial damage and repair. In addition, oligodendrocyte pathology was studied in early human NMO lesions. Apart from early complement-mediated astrocyte destruction, we observed a prominent, very early loss of oligodendrocytes and oligodendrocyte precursor cells (OPCs) as well as a delayed loss of myelin. Astrocyte repopulation of focal NMO lesions was already substantial after 1 week. Olig2-positive OPCs reappeared before NogoA-positive, mature oligodendrocytes. Thus, using two experimental models that closely mimic the human disease, our study demonstrates that oligodendrocyte and OPC loss is an extremely early feature in the formation of human and experimental NMO lesions and leads to subsequent, delayed demyelination, highlighting an important difference in the pathogenesis of MS and NMO.

  8. SOX2+ cell population from normal human brain white matter is able to generate mature oligodendrocytes.

    Directory of Open Access Journals (Sweden)

    Jorge Oliver-De La Cruz

    Full Text Available OBJECTIVES: A number of neurodegenerative diseases progress with a loss of myelin, which makes them candidate diseases for the development of cell-replacement therapies based on mobilisation or isolation of the endogenous neural/glial progenitor cells, in vitro expansion, and further implantation. Cells expressing A2B5 or PDGFRA/CNP have been isolated within the pool of glial progenitor cells in the subcortical white matter of the normal adult human brain, all of which demonstrate glial progenitor features. However, the heterogeneity and differentiation potential of this pool of cells is not yet well established. METHODS: We used diffusion tensor images, histopathology, and immunostaining analysis to demonstrate normal cytoarchitecture and the absence of abnormalities in human temporal lobe samples from patients with mesial temporal sclerosis. These samples were used to isolate and enrich glial progenitor cells in vitro, and later to detect such cells in vivo. RESULTS: We have identified a subpopulation of SOX2+ cells, most of them co-localising with OLIG2, in the white matter of the normal adult human brain in vivo. These cells can be isolated and enriched in vitro, where they proliferate and generate immature (O4+ and mature (MBP+ oligodendrocytes and, to a lesser extent, astrocytes (GFAP+. CONCLUSION: Our results demonstrate the existence of a new glial progenitor cell subpopulation that expresses SOX2 in the white matter of the normal adult human brain. These cells might be of use for tissue regeneration procedures.

  9. Comparative Effects of Human Neural Stem Cells and Oligodendrocyte Progenitor Cells on the Neurobehavioral Disorders of Experimental Autoimmune Encephalomyelitis Mice

    Directory of Open Access Journals (Sweden)

    Dae-Kwon Bae

    2016-01-01

    Full Text Available Since multiple sclerosis (MS is featured with widespread demyelination caused by autoimmune response, we investigated the recovery effects of F3.olig2 progenitors, established by transducing human neural stem cells (F3 NSCs with Olig2 transcription factor, in myelin oligodendrocyte glycoprotein- (MOG- induced experimental autoimmune encephalomyelitis (EAE model mice. Six days after EAE induction, F3 or F3.olig2 cells (1 × 106/mouse were intravenously transplanted. MOG-injected mice displayed severe neurobehavioral deficits which were remarkably attenuated and restored by cell transplantation, in which F3.olig2 cells were superior to its parental F3 cells. Transplanted cells migrated to the injured spinal cord, matured to oligodendrocytes, and produced myelin basic proteins (MBP. The F3.olig2 cells expressed growth and neurotrophic factors including brain-derived neurotrophic factor (BDNF, nerve growth factor (NGF, ciliary neurotrophic factor (CNTF, and leukemia inhibitory factor (LIF. In addition, the transplanted cells markedly attenuated inflammatory cell infiltration, reduced cytokine levels in the spinal cord and lymph nodes, and protected host myelins. The results indicate that F3.olig2 cells restore neurobehavioral symptoms of EAE mice by regulating autoimmune inflammatory responses as well as by stimulating remyelination and that F3.olig2 progenitors could be a candidate for the cell therapy of demyelinating diseases including MS.

  10. A functional progesterone receptor is required for immunomodulation, reduction of reactive gliosis and survival of oligodendrocyte precursors in the injured spinal cord.

    Science.gov (United States)

    Labombarda, Florencia; Jure, Ignacio; Gonzalez, Susana; Lima, Analia; Roig, Paulina; Guennoun, Rachida; Schumacher, Michael; De Nicola, Alejandro F

    2015-11-01

    The anti-inflammatory effects of progesterone have been increasingly recognized in several neuropathological models, including spinal cord inflammation. In the present investigation, we explored the regulation of proinflammatory factors and enzymes by progesterone at several time points after spinal cord injury (SCI) in male rats. We also demonstrated the role of the progesterone receptor (PR) in inhibiting inflammation and reactive gliosis, and in enhancing the survival of oligodendrocyte progenitors cells (OPC) in injured PR knockout (PRKO) mice receiving progesterone. First, after SCI in rats, progesterone greatly attenuated the injury-induced hyperexpression of the mRNAs of interleukin 1β (IL1β), IL6, tumor necrosis factor alpha (TNFα), inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2), all involved in oligodendrocyte damage. Second, the role of the PR was investigated in PRKO mice after SCI, in which progesterone failed to reduce the high expression of IL1β, IL6, TNFα and IκB-α mRNAs, the latter being considered an index of reduced NF-κB transactivation. These effects occurred in a time framework coincident with a reduction in the astrocyte and microglial responses. In contrast to wild-type mice, progesterone did not increase the density of OPC and did not prevent apoptotic death of these cells in PRKO mice. Our results support a role of PR in: (a) the anti-inflammatory effects of progesterone; (b) the modulation of astrocyte and microglial responses and (c) the prevention of OPC apoptosis, a mechanism that would enhance the commitment of progenitors to the remyelination pathway in the injured spinal cord.

  11. PDGF is required for remyelination-promoting IgM stimulation of oligodendrocyte progenitor cell proliferation.

    Directory of Open Access Journals (Sweden)

    Jens O Watzlawik

    Full Text Available BACKGROUND: Promotion of remyelination is a major goal in treating demyelinating diseases such as multiple sclerosis (MS. The recombinant human monoclonal IgM, rHIgM22, targets myelin and oligodendrocytes (OLs and promotes remyelination in animal models of MS. It is unclear whether rHIgM22-mediated stimulation of lesion repair is due to promotion of oligodendrocyte progenitor cell (OPC proliferation and survival, OPC differentiation into myelinating OLs or protection of mature OLs. It is also unknown whether astrocytes or microglia play a functional role in IgM-mediated lesion repair. METHODS: We assessed the effect of rHIgM22 on cell proliferation in mixed CNS glial and OPC cultures by tritiated-thymidine uptake and by double-label immunocytochemistry using the proliferation marker, Ki-67. Antibody-mediated signaling events, OPC differentiation and OPC survival were investigated and quantified by Western blots. RESULTS: rHIgM22 stimulates OPC proliferation in mixed glial cultures but not in purified OPCs. There is no proliferative response in astrocytes or microglia. rHIgM22 activates PDGFαR in OPCs in mixed glial cultures. Blocking PDGFR-kinase inhibits rHIgM22-mediated OPC proliferation in mixed glia. We confirm in isolated OPCs that rHIgM22-mediated anti-apoptotic signaling and inhibition of OPC differentiation requires PDGF and FGF-2. We observed no IgM-mediated effect in mature OLs in the absence of PDGF and FGF-2. CONCLUSION: Stimulation of OPC proliferation by rHIgM22 depends on co-stimulatory astrocytic and/or microglial factors. We demonstrate that rHIgM22-mediated activation of PDGFαR is required for stimulation of OPC proliferation. We propose that rHIgM22 lowers the PDGF threshold required for OPC proliferation and protection, which can result in remyelination of CNS lesions.

  12. MK-801 treatment affects glycolysis in oligodendrocytes more than in astrocytes and neuronal cells: insights for schizophrenia

    Directory of Open Access Journals (Sweden)

    Paul C Guest

    2015-05-01

    Full Text Available As a multifactorial disease, the underlying causes of schizophrenia require analysis by multiplex methods such as proteomics to allow identification of whole protein networks. Previous post-mortem proteomic studies on brain tissues from schizophrenia patients have demonstrated changes in activation of glycolytic and energy metabolism pathways. However, it is not known whether these changes occur in neurons or in glial cells. To address this question, we treated neuronal, astrocyte and oligodendrocyte cell lines with the NMDA receptor antagonist MK-801 and measured the levels of six glycolytic enzymes by Western blot analysis. MK-801 acts on the glutamatergic system and has been proposed as a pharmacological means of modeling schizophrenia. Treatment with MK-801 resulted in significant changes in the levels of glycolytic enzymes in all cell types. Most of the differences were found in oligodendrocytes, which had altered levels of hexokinase 1 (HK1, enolase 2 (ENO2, phosphoglycerate kinase (PGK and phosphoglycerate mutase 1 (PGAM1 after acute MK-801 treatment (8 hours, and HK1, ENO2, PGK and triosphosphate isomerase (TPI following long term treatment (72 hours. Addition of the antipsychotic clozapine to the cultures resulted in counter-regulatory effects to the MK-801 treatment by normalizing the levels of ENO2 and PGK in both the acute and long term cultures. In astrocytes, MK-801 affected only aldolase C (ALDOC under both acute conditions and HK1 and ALDOC following long term treatment, and TPI was the only enzyme affected under long term conditions in the neuronal cells. In conclusion, MK-801 affects glycolysis in oligodendrocytes to a larger extent than neuronal cells and this may be modulated by antipsychotic treatment. Although cell culture studies do not necessarily reflect the in vivo pathophysiology and drug effects within the brain, these results suggest that neurons, astrocytes and oligodendrocytes are affected differently in

  13. What is the potential of oligodendrocyte progenitor cells to successfully treat human spinal cord injury?

    Directory of Open Access Journals (Sweden)

    Yeung Trevor M

    2011-09-01

    Full Text Available Abstract Background Spinal cord injury is a serious and debilitating condition, affecting millions of people worldwide. Long seen as a permanent injury, recent advances in stem cell research have brought closer the possibility of repairing the spinal cord. One such approach involves injecting oligodendrocyte progenitor cells, derived from human embryonic stem cells, into the injured spinal cord in the hope that they will initiate repair. A phase I clinical trial of this therapy was started in mid 2010 and is currently underway. Discussion The theory underlying this approach is that these myelinating progenitors will phenotypically replace myelin lost during injury whilst helping to promote a repair environment in the lesion. However, the importance of demyelination in the pathogenesis of human spinal cord injury is a contentious issue and a body of literature suggests that it is only a minor factor in the overall injury process. Summary This review examines the validity of the theory underpinning the on-going clinical trial as well as analysing published data from animal models and finally discussing issues surrounding safety and purity in order to assess the potential of this approach to successfully treat acute human spinal cord injury.

  14. How to make an oligodendrocyte

    DEFF Research Database (Denmark)

    Goldman, Steven A.; Kuypers, Nicholas J.

    2015-01-01

    and cerebral palsy, to multiple sclerosis and white matter stroke. Accordingly, replacing lost oligodendrocytes, whether by transplanting oligodendrocyte progenitor cells (OPCs) or by mobilizing endogenous progenitors, holds great promise as a therapeutic strategy for the diseases of central white matter....... In this Primer, we describe the molecular events regulating oligodendrocyte development and how our understanding of this process has led to the establishment of methods for producing OPCs and oligodendrocytes from embryonic stem cells and induced pluripotent stem cells, as well as directly from somatic cells....... In addition, we will discuss the safety of engrafted stem cell-derived OPCs, as well as approaches by which to modulate their differentiation and myelinogenesis in vivo following transplantation....

  15. Expression and regulation of versican in neural precursor cells and their lineages

    Institute of Scientific and Technical Information of China (English)

    Wen-li GU; Sai-li FU; Yan-xia WANG; Ying LI; Xiao-fei WANG; Xiao-ming XU; Pei-hua LU

    2007-01-01

    Aim: To have a better understanding of the expression and regulation of versican isoforms in neural precursor cells (NPC) and oligodendrogliogenesis. Methods:By immunocytochemistry, RT-PCR, and real-time PCR, we examined the temporal expression of versican in NPC isolated from embryonic d 16 rats as well as in oligodendrocyte (OL) lineage cells induced to differentiate from NPC,which mimicked the oligodendrogliogenesis in vivo. Results: We found that versican was constitutively expressed in NPC and their lineage cells, including neurons, astrocytes, and OL. In addition, 2 versican isoforms, V1/V0 and V2,were found to express at low levels in NPC, but at significantly higher levels in OL lineage cells. The peak expression of versican V2 was found at the oligodendrocyte precursor cell stage. Furthermore, the treatment of 2 pro-inflammatory cytokines, TNF-α and IFN-γ, enhanced the transcription of versican V2 in NPC in a dose-dependent manner, but showed no effect on V1/V0 expression.Conclusion: Taken together, our results demonstrate that versican, particularly the inhibitory V2 isoform, is increasingly expressed in OL lineage cells induced to differentiate from NPC. An increase in versican V2 expression after cytokine stimulation implies the interplay between the injury-induced upregulation of inflammatory cytokines and chondroitin sulfate proteoglycan-mediated inhibition of axonal regeneration after central nervous system injury.

  16. 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

  17. Regulation of Oligodendrocyte Progenitor Cell Maturation by PPARδ: Effects on Bone Morphogenetic Proteins

    Directory of Open Access Journals (Sweden)

    Maria Vittoria Simonini

    2009-12-01

    Full Text Available In EAE (experimental autoimmune encephalomyelitis, agonists of PPARs (peroxisome proliferator-activated receptors provide clinical benefit and reduce damage. In contrast with PPARγ, agonists of PPARδ are more effective when given at later stages of EAE and increase myelin gene expression, suggesting effects on OL (oligodendrocyte maturation. In the present study we examined effects of the PPARδ agonist GW0742 on OPCs (OL progenitor cells, and tested whether the effects involve modulation of BMPs (bone morphogenetic proteins. We show that effects of GW0742 are mediated through PPARδ since no amelioration of EAE clinical scores was observed in PPARδ-null mice. In OPCs derived from E13 mice (where E is embryonic day, GW0742, but not the PPARγ agonist pioglitazone, increased the number of myelin-producing OLs. This was due to activation of PPARδ since process formation was reduced in PPARδ-null compared with wild-type OPCs. In both OPCs and enriched astrocyte cultures, GW0742 increased noggin protein expression; however, noggin mRNA was only increased in astrocytes. In contrast, GW0742 reduced BMP2 and BMP4 mRNA levels in OPCs, with lesser effects in astrocytes. These findings demonstrate that PPARδ plays a role in OPC maturation, mediated, in part, by regulation of BMP and BMP antagonists.

  18. Lipopolysaccharide-activated microglia induce death of oligodendrocyte progenitor cells and impede their development.

    Science.gov (United States)

    Pang, Y; Campbell, L; Zheng, B; Fan, L; Cai, Z; Rhodes, P

    2010-03-17

    Damage to oligodendrocyte (OL) progenitor cells (OPCs) and hypomyelination are two hallmark features of periventricular leukomalacia (PVL), the most common form of brain damage in premature infants. Clinical and animal studies have linked the incidence of PVL to maternal infection/inflammation, and activated microglia have been proposed to play a central role. However, the precise mechanism of how activated microglia adversely affects the survival and development of OPCs is still not clear. Here we demonstrate that lipopolysaccharide (LPS)-activated microglia are deleterious to OPCs, that is, impeding OL lineage progression, reducing the production of myelin basic protein (MBP), and mediating OPC death. We further demonstrate that LPS-activated microglia mediate OPC death by two distinct mechanisms in a time-dependent manner. The early phase of cell damage occurs within 24 h after LPS treatment, which is mediated by nitric oxide (NO)-dependent oxidative damage and is prevented by N(G)-nitro-l-arginine methyl ester (l-NAME), a general inhibitor of nitric oxide synthase. The delayed cell death is evident at 48 h after LPS treatment, is mediated by cytokines, and is prevented by blocking the activity of tumor necrosis factor-alpha (TNF-alpha) and pro-nerve growth factor (proNGF), but not by l-NAME. Furthermore, microglia-derived insulin-like growth factor-1 (IGF-1) and ciliary neurotrophic factor (CNTF) were significantly suppressed by LPS, and exogenous IGF-1 and CNTF synergistically protected OLs from death induced by LPS-treated microglia conditioned medium, indicating that a deficiency in trophic support may also be involved in OL death. Our finding that LPS-activated microglia not only induce two waves of cell death but also greatly impair OL development may shed some light on the mechanisms underlying selective white matter damage and hypomyelination in PVL.

  19. Bioenergetic Failure in Rat Oligodendrocyte Progenitor Cells Treated with Cerebrospinal Fluid Derived from Multiple Sclerosis Patients

    Directory of Open Access Journals (Sweden)

    Deepali Mathur

    2017-07-01

    Full Text Available In relapsing-remitting multiple sclerosis (RRMS subtype, the patient’s brain itself is capable of repairing the damage, remyelinating the axon and recovering the neurological function. Cerebrospinal fluid (CSF is in close proximity with brain parenchyma and contains a host of proteins and other molecules, which influence the cellular physiology, that may balance damage and repair of neurons and glial cells. The purpose of this study was to determine the pathophysiological mechanisms underpinning myelin repair in distinct clinical forms of MS and neuromyelitis optica (NMO patients by studying the effect of diseased CSF on glucose metabolism and ATP synthesis. A cellular model with primary cultures of oligodendrocyte progenitor cells (OPCs from rat cerebrum was employed, and cells were treated with CSF from distinct clinical forms of MS, NMO patients and neurological controls. Prior to comprehending mechanisms underlying myelin repair, we determine the best stably expressed reference genes in our experimental condition to accurately normalize our target mRNA transcripts. The GeNorm and NormFinder algorithms showed that mitochondrial ribosomal protein (Mrpl19, hypoxanthine guanine phosphoribosyl transferase (Hprt, microglobulin β2 (B2m, and transferrin receptor (Tfrc were identified as the best reference genes in OPCs treated with MS subjects and were used for normalizing gene transcripts. The main findings on microarray gene expression profiling analysis on CSF treated OPCs cells revealed a disturbed carbohydrate metabolism and ATP synthesis in MS and NMO derived CSF treated OPCs. In addition, using STRING program, we investigate whether gene–gene interaction affected the whole network in our experimental conditions. Our findings revealed downregulated expression of genes involved in carbohydrate metabolism, and that glucose metabolism impairment and reduced ATP availability for cellular damage repair clearly differentiate more benign forms

  20. Electroacupuncture promotes the proliferation of endogenous neural stem cells and oligodendrocytes in the injured spinal cord of adult rats

    Institute of Scientific and Technical Information of China (English)

    Haiying Wu; Min Hu; Dekai Yuan; Yunhui Wang; Jing Wang; Tao Li; Chuanyun Qian

    2012-01-01

    A contusive model of spinal cord injury at spinal segment T8-9 was established in rats. Huantiao (GB30) and Huatuojiaji (Ex-B05) were punctured with needles, and endogenous neural stem cells were labeled with 5-bromo-2'-deoxyuridine (BrdU) and NG2. Double immunofluorescence staining showed that electroacupuncture markedly increased the numbers of BrdU+/NG2+ cells at spinal cord tissue 15 mm away from the injury center in the rostral and caudal directions. The results suggest that electroacupuncture promotes the proliferation of endogenous neural stem cells and oligodendrocytes in rats with spinal cord injury.

  1. Protandim Protects Oligodendrocytes against an Oxidative Insult

    Directory of Open Access Journals (Sweden)

    Jamie L. Lim

    2016-09-01

    Full Text Available Oligodendrocyte damage and loss are key features of multiple sclerosis (MS pathology. Oligodendrocytes appear to be particularly vulnerable to reactive oxygen species (ROS and cytokines, such as tumor necrosis factor-α (TNF, which induce cell death and prevent the differentiation of oligodendrocyte progenitor cells (OPCs. Here, we investigated the efficacy of sulforaphane (SFN, monomethyl fumarate (MMF and Protandim to induce Nrf2-regulated antioxidant enzyme expression, and protect oligodendrocytes against ROS-induced cell death and ROS-and TNF-mediated inhibition of OPC differentiation. OLN-93 cells and primary rat oligodendrocytes were treated with SFN, MMF or Protandim resulting in significant induction of Nrf2-driven (antioxidant proteins heme oygenase-1, nicotinamide adenine dinucleotide phosphate (NADPH: quinone oxidoreductase-1 and p62/SQSTM1, as analysed by Western blotting. After incubation with the compounds, oligodendrocytes were exposed to hydrogen peroxide. Protandim most potently promoted oligodendrocyte cell survival as measured by live/death viability assay. Moreover, OPCs were treated with Protandim or vehicle control prior to exposing them to TNF or hydrogen peroxide for five days, which inhibited OPC differentiation. Protandim significantly promoted OPC differentiation under influence of ROS, but not TNF. Protandim, a combination of five herbal ingredients, potently induces antioxidants in oligodendrocytes and is able to protect oligodendrocytes against oxidative stress by preventing ROS-induced cell death and promoting OPC differentiation.

  2. Systematic Review of Pharmacological Properties of the Oligodendrocyte Lineage

    Science.gov (United States)

    Marinelli, Carla; Bertalot, Thomas; Zusso, Morena; Skaper, Stephen D.; Giusti, Pietro

    2016-01-01

    Oligodendrogenesis and oligodendrocyte precursor maturation are essential processes during the course of central nervous system development, and lead to the myelination of axons. Cells of the oligodendrocyte lineage are generated in the germinal zone from migratory bipolar oligodendrocyte precursor cells (OPCs), and acquire cell surface markers as they mature and respond specifically to factors which regulate proliferation, migration, differentiation, and survival. Loss of myelin underlies a wide range of neurological disorders, some of an autoimmune nature—multiple sclerosis probably being the most prominent. Current therapies are based on the use of immunomodulatory agents which are likely to promote myelin repair (remyelination) indirectly by subverting the inflammatory response, aspects of which impair the differentiation of OPCs. Cells of the oligodendrocyte lineage express and are capable of responding to a diverse array of ligand-receptor pairs, including neurotransmitters and nuclear receptors such as γ-aminobutyric acid, glutamate, adenosine triphosphate, serotonin, acetylcholine, nitric oxide, opioids, prostaglandins, prolactin, and cannabinoids. The intent of this review is to provide the reader with a synopsis of our present state of knowledge concerning the pharmacological properties of the oligodendrocyte lineage, with particular attention to these receptor-ligand (i.e., neurotransmitters and nuclear receptor) interactions that can influence oligodendrocyte migration, proliferation, differentiation, and myelination, and an appraisal of their therapeutic potential. For example, many promising mediators work through Ca2+ signaling, and the balance between Ca2+ influx and efflux can determine the temporal and spatial properties of oligodendrocytes (OLs). Moreover, Ca2+ signaling in OPCs can influence not only differentiation and myelination, but also process extension and migration, as well as cell death in mature mouse OLs. There is also evidence

  3. Protective Effects of N-Acetyl-L-Cysteine in Human Oligodendrocyte Progenitor Cells and Restoration of Motor Function in Neonatal Rats with Hypoxic-Ischemic Encephalopathy

    Directory of Open Access Journals (Sweden)

    Dongsun Park

    2015-01-01

    Full Text Available Objective. Since oligodendrocyte progenitor cells (OPCs are the target cells of neonatal hypoxic-ischemic encephalopathy (HIE, the present study was aimed at investigating the protective effects of N-acetyl-L-cysteine (NAC, a well-known antioxidant and precursor of glutathione, in OPCs as well as in neonatal rats. Methods. In in vitro study, protective effects of NAC on KCN cytotoxicity in F3.Olig2 OPCs were investigated via MTT assay and apoptotic signal analysis. In in vivo study, NAC was administered to rats with HIE induced by hypoxia-ischemia surgery at postnatal day 7, and their motor functions and white matter demyelination were analyzed. Results. NAC decreased KCN cytotoxicity in F3.Olig2 cells and especially suppressed apoptosis by regulating Bcl2 and p-ERK. Administration of NAC recovered motor functions such as the using ratio of forelimb contralateral to the injured brain, locomotor activity, and rotarod performance of neonatal HIE animals. It was also confirmed that NAC attenuated demyelination in the corpus callosum, a white matter region vulnerable to HIE. Conclusion. The results indicate that NAC exerts neuroprotective effects in vitro and in vivo by preserving OPCs, via regulation of antiapoptotic signaling, and that F3.Olig2 human OPCs could be a good tool for screening of candidates for demyelinating diseases.

  4. Accelerated generation of oligodendrocyte progenitor cells from human induced pluripotent stem cells by forced expression of Sox10 and Olig2.

    Science.gov (United States)

    Li, Pengyan; Li, Mo; Tang, Xihe; Wang, Shuyan; Zhang, Y Alex; Chen, Zhiguo

    2016-11-01

    Oligodendrocyte progenitor cells (OPCs) hold great promise for treatment of dysmyelinating disorders, such as multiple sclerosis and cerebral palsy. Recent studies on generation of human OPCs mainly use human embryonic stem cells (hESCs) or neural stem cells (NSCs) as starter cell sources for the differentiation process. However, NSCs are restricted in availability and the present method for generation of oligodendrocytes (OLs) from ESCs often requires a lengthy period of time. Here, we demonstrated a protocol to efficiently derive OPCs from human induced pluripotent stem cells (hiPSCs) by forced expression of two transcription factors (2TFs), Sox10 and Olig2. With this method, PDGFRα(+) OPCs can be obtained in 14 days and O4(+) OPCs in 56 days. Furthermore, OPCs may be able to differentiate to mature OLs that could ensheath axons when co-cultured with rat cortical neurons. The results have implications in the development of autologous cell therapies.

  5. Glial-restricted precursors as potential candidates for ALS cell-replacement therapy.

    Science.gov (United States)

    Kruminis-Kaszkiel, Ewa; Wojtkiewicz, Joanna; Maksymowicz, Wojciech

    2014-01-01

    Amyotrophic lateral sclerosis is a multifactorial progressive neurodegenerative disorder leading to severe disability and death within 3-5 years after diagnosis. The main mechanisms underlying the disease progression are poorly known but according to the current knowledge, neuroinflammation is a key player in motor neurons damage. Astrocytes constitute an important cell population involved in neuroinflammatory reaction. Many studies confirmed their striking connection with motor neuron pathology and therefore they might be a target for the treatment of ALS. Cell-based therapy appears to be a promising strategy. Since direct replacement or restoring of motor neurons using various stem cells is challenging, enrichment of healthy donor-derived astrocytes appears to be a more realistic and beneficial approach. The effects of astrocytes have been examined using transplantation of glial-restricted precursors (GRPs) that represent one of the earliest precursors within the oligodendrocytic and astrocytic cell lineage. In this review, we focused on evidence-based data on astrocyte replacement transplantation therapy using GRPs in animal models of motor neuron diseases. The efficacy of GRPs engrafting is very encouraging. Furthermore, the lesson learned from application of lineage-restricted precursors in spinal cord injury (SCI) indicates that differentiation of GRPs into astrocytes before transplantation might be more advantageous in the context of axon regeneration. To sum up, the studies of glial-restricted precursors have made a step forward to ALS research and might bring breakthroughs to the field of ALS therapy in the future.

  6. Human embryonic stem cell-derived oligodendrocyte progenitors aid in functional recovery of sensory pathways following contusive spinal cord injury.

    Directory of Open Access Journals (Sweden)

    Angelo H All

    Full Text Available BACKGROUND: Transplantations of human stem cell derivatives have been widely investigated in rodent models for the potential restoration of function of neural pathways after spinal cord injury (SCI. Studies have already demonstrated cells survival following transplantation in SCI. We sought to evaluate survival and potential therapeutic effects of transplanted human embryonic stem (hES cell-derived oligodendrocyte progenitor cells (OPCs in a contusive injury in rats. Bioluminescence imaging was utilized to verify survivability of cells up to 4 weeks, and somatosensory evoked potential (SSEPs were recorded at the cortex to monitor function of sensory pathways throughout the 6-week recovery period. PRINCIPAL FINDINGS: hES cells were transduced with the firefly luciferase gene and differentiated into OPCs. OPCs were transplanted into the lesion epicenter of rat spinal cords 2 hours after inducing a moderate contusive SCI. The hES-treatment group showed improved SSEPs, including increased amplitude and decreased latencies, compared to the control group. The bioluminescence of transplanted OPCs decreased by 97% in the injured spinal cord compared to only 80% when injected into an uninjured spinal cord. Bioluminescence increased in both experimental groups such that by week 3, no statistical difference was detected, signifying that the cells survived and proliferated independent of injury. Post-mortem histology of the spinal cords showed integration of human cells expressing mature oligodendrocyte markers and myelin basic protein without the expression of markers for astrocytes (GFAP or pluripotent cells (OCT4. CONCLUSIONS: hES-derived OPCs transplanted 2 hours after contusive SCI survive and differentiate into OLs that produce MBP. Treated rats demonstrated functional improvements in SSEP amplitudes and latencies compared to controls as early as 1 week post-injury. Finally, the hostile injury microenvironment at 2 hours post-injury initially caused

  7. The balance between oligodendrocyte and astrocyte production in major white matter tracts is linearly related to serum total thyroxine

    Science.gov (United States)

    Thyroid hormone (TH) may control the ratio of oligodendrocytes to astrocytes in white matter by acting on a common precursor of these two cell types. If so, then TH should produce an equal but opposite effect on the density of these two cells types across all TH levels. To test t...

  8. Protective Effect of Electroacupuncture on Neural Myelin Sheaths is Mediated via Promotion of Oligodendrocyte Proliferation and Inhibition of Oligodendrocyte Death After Compressed Spinal Cord Injury.

    Science.gov (United States)

    Huang, Siqin; Tang, Chenglin; Sun, Shanquan; Cao, Wenfu; Qi, Wei; Xu, Jin; Huang, Juan; Lu, Weitian; Liu, Qian; Gong, Biao; Zhang, Yi; Jiang, Jin

    2015-12-01

    Electroacupuncture (EA) has been used worldwide to treat demyelinating diseases, but its therapeutic mechanism is poorly understood. In this study, a custom-designed model of compressed spinal cord injury (CSCI) was used to induce demyelination. Zusanli (ST36) and Taixi (KI3) acupoints of adult rats were stimulated by EA to demonstrate its protective effect. At 14 days after EA, both locomotor skills and ultrastructural features of myelin sheath were significantly improved. Phenotypes of proliferating cells were identified by double immunolabeling of 5-ethynyl-2'-deoxyuridine with antibodies to cell markers: NG2 [oligodendrocyte precursor cell (OPC) marker], 2',3'-cyclic-nucleotide 3'-phosphodiesterase (CNPase) (oligodendrocyte marker), and glial fibrillary acidic protein (GFAP) (astrocyte marker). EA enhanced the proliferation of OPCs and CNPase, as well as the differentiation of OPCs by promoting Olig2 (the basic helix-loop-helix protein) and attenuating Id2 (the inhibitor of DNA binding 2). EA could also improve myelin basic protein (MBP) and protect existing oligodendrocytes from apoptosis by inhibiting caspase-12 (a representative of endoplasmic reticulum stress) and cytochrome c (an apoptotic factor and hallmark of mitochondria). Therefore, our results indicate that the protective effect of EA on neural myelin sheaths is mediated via promotion of oligodendrocyte proliferation and inhibition of oligodendrocyte death after CSCI.

  9. Separation of rare oligodendrocyte progenitor cells from brain using a high-throughput multilayer thermoplastic-based microfluidic device.

    Science.gov (United States)

    Didar, Tohid Fatanat; Li, Kebin; Veres, Teodor; Tabrizian, Maryam

    2013-07-01

    Despite the advances made in the field of regenerative medicine, the progress in cutting-edge technologies for separating target therapeutic cells are still at early stage of development. These cells are often rare, such as stem cells or progenitor cells that their overall properties should be maintained during the separation process for their subsequent application in regenerative medicine. This work, presents separation of oligodendrocyte progenitor cells (OPCs) from rat brain primary cultures using an integrated thermoplastic elastomeric (TPE)- based multilayer microfluidic device fabricated using hot-embossing technology. OPCs are frequently used in recovery, repair and regeneration of central nervous system after injuries. Indeed, their ability to differentiate in vitro into myelinating oligodendrocytes, are extremely important for myelin repair. OPCs form 5-10% of the glial cells population. The traditional macroscale techniques for OPCs separation require pre-processing of cells and/or multiple time consuming steps with low efficiency leading very often to alteration of their properties. The proposed methodology implies to separate OPCs based on their smaller size compared to other cells from the brain tissue mixture. Using aforementioned microfluidic chip embedded with a 5 μm membrane pore size and micropumping system, a separation efficiency more than 99% was achieved. This microchip was able to operate at flow rates up to 100 μl/min, capable of separating OPCs from a confluent 75 cm(2) cell culture flask in less than 10 min, which provides us with a high-throughput and highly efficient separation expected from any cell sorting techniques.

  10. Prox1 Inhibits Proliferation and Is Required for Differentiation of the Oligodendrocyte Cell Lineage in the Mouse.

    Directory of Open Access Journals (Sweden)

    Kentaro Kato

    Full Text Available Central nervous system injury induces a regenerative response in ensheathing glial cells comprising cell proliferation, spontaneous axonal remyelination, and limited functional recovery, but the molecular mechanisms are not fully understood. In Drosophila, this involves the genes prospero and Notch controlling the balance between glial proliferation and differentiation, and manipulating their levels in glia can switch the response to injury from prevention to promotion of repair. In the mouse, Notch1 maintains NG2 oligodendrocyte progenitor cells (OPCs in a progenitor state, but what factor may enable oligodendrocyte (OL differentiation and functional remyelination is not understood. Here, we asked whether the mammalian homologue of prospero, Prox1, is involved. Our data show that Prox1 is distributed in NG2+ OPCs and in OLs in primary cultured cells, and in the mouse spinal cord in vivo. siRNA prox1 knockdown in primary OPCs increased cell proliferation, increased NG2+ OPC cell number and decreased CC1+ OL number. Prox1 conditional knockout in the OL cell lineage in mice increased NG2+ OPC cell number, and decreased CC1+ OL number. Lysolecithin-induced demyelination injury caused a reduction in CC1+ OLs in homozygous Prox1-/- conditional knockout mice compared to controls. Remarkably, Prox1-/- conditional knockout mice had smaller lesions than controls. Altogether, these data show that Prox1 is required to inhibit OPC proliferation and for OL differentiation, and could be a relevant component of the regenerative glial response. Therapeutic uses of glia and stem cells to promote regeneration and repair after central nervous system injury would benefit from manipulating Prox1.

  11. Protandim Protects Oligodendrocytes against an Oxidative Insult

    NARCIS (Netherlands)

    Lim, Jamie L; van der Pol, Susanne M A; Baron, Wia; McCord, Joe M; de Vries, Helga E; van Horssen, Jack

    2016-01-01

    Oligodendrocyte damage and loss are key features of multiple sclerosis (MS) pathology. Oligodendrocytes appear to be particularly vulnerable to reactive oxygen species (ROS) and cytokines, such as tumor necrosis factor-α (TNF), which induce cell death and prevent the differentiation of

  12. Protandim Protects Oligodendrocytes against an Oxidative Insult

    NARCIS (Netherlands)

    Lim, Jamie L; van der Pol, Susanne M A; Baron, Wia; McCord, Joe M; de Vries, Helga E; van Horssen, Jack

    2016-01-01

    Oligodendrocyte damage and loss are key features of multiple sclerosis (MS) pathology. Oligodendrocytes appear to be particularly vulnerable to reactive oxygen species (ROS) and cytokines, such as tumor necrosis factor-α (TNF), which induce cell death and prevent the differentiation of oligodendrocy

  13. Properties and fate of oligodendrocyte progenitor cells in the corpus callosum, motor cortex, and piriform cortex of the mouse.

    Science.gov (United States)

    Clarke, Laura E; Young, Kaylene M; Hamilton, Nicola B; Li, Huiliang; Richardson, William D; Attwell, David

    2012-06-13

    Oligodendrocyte progenitor cells (OPCs) in the postnatal mouse corpus callosum (CC) and motor cortex (Ctx) reportedly generate only oligodendrocytes (OLs), whereas those in the piriform cortex may also generate neurons. OPCs have also been subdivided based on their expression of voltage-gated ion channels, ability to respond to neuronal activity, and proliferative state. To determine whether OPCs in the piriform cortex have inherently different physiological properties from those in the CC and Ctx, we studied acute brain slices from postnatal transgenic mice in which GFP expression identifies OL lineage cells. We whole-cell patch clamped GFP-expressing (GFP(+)) cells within the CC, Ctx, and anterior piriform cortex (aPC) and used prelabeling with 5-ethynyl-2'-deoxyuridine (EdU) to assess cell proliferation. After recording, slices were immunolabeled and OPCs were defined by strong expression of NG2. NG2(+) OPCs in the white and gray matter proliferated and coexpressed PDGFRα and voltage-gated Na(+) channels (I(Na)). Approximately 70% of OPCs were capable of generating regenerative depolarizations. In addition to OLIG2(+) NG2(+) I(Na)(+) OPCs and OLIG2(+) NG2(neg) I(Na)(neg) OLs, we identified cells with low levels of NG2 limited to the soma or the base of some processes. These cells had a significantly reduced I(Na) and a reduced ability to incorporate EdU when compared with OPCs and probably correspond to early differentiating OLs. By combining EdU labeling and lineage tracing using Pdgfrα-CreER(T2) : R26R-YFP transgenic mice, we double labeled OPCs and traced their fate in the postnatal brain. These OPCs generated OLs but did not generate neurons in the aPC or elsewhere at any time that we examined.

  14. In vitro expanded stem cells from the developing retina fail to generate photoreceptors but differentiate into myelinating oligodendrocytes.

    Directory of Open Access Journals (Sweden)

    Magdalena Czekaj

    Full Text Available Cell transplantation to treat retinal degenerative diseases represents an option for the replacement of lost photoreceptor cells. In vitro expandable cells isolated from the developing mammalian retina have been suggested as a potential source for the generation of high numbers of donor photoreceptors. In this study we used standardized culture conditions based on the presence of the mitogens FGF-2 and EGF to generate high numbers of cells in vitro from the developing mouse retina. These presumptive 'retinal stem cells' ('RSCs' can be propagated as monolayer cultures over multiple passages, express markers of undifferentiated neural cells, and generate neuronal and glial cell types upon withdrawal of mitogens in vitro or following transplantation into the adult mouse retina. The proportion of neuronal differentiation can be significantly increased by stepwise removal of mitogens and inhibition of the notch signaling pathway. However, 'RSCs', by contrast to their primary counterparts in vivo, i.e. retinal progenitor cells, loose the expression of retina-specific progenitor markers like Rax and Chx10 after passaging and fail to differentiate into photoreceptors both in vitro or after intraretinal transplantation. Notably, 'RSCs' can be induced to differentiate into myelinating oligodendrocytes, a cell type not generated by primary retinal progenitor cells. Based on these findings we conclude that 'RSCs' expanded in high concentrations of FGF-2 and EGF loose their retinal identity and acquire features of in vitro expandable neural stem-like cells making them an inappropriate cell source for strategies aimed at replacing photoreceptor cells in the degenerated retina.

  15. In vitro expanded stem cells from the developing retina fail to generate photoreceptors but differentiate into myelinating oligodendrocytes.

    Science.gov (United States)

    Czekaj, Magdalena; Haas, Jochen; Gebhardt, Marlen; Müller-Reichert, Thomas; Humphries, Peter; Farrar, Jane; Bartsch, Udo; Ader, Marius

    2012-01-01

    Cell transplantation to treat retinal degenerative diseases represents an option for the replacement of lost photoreceptor cells. In vitro expandable cells isolated from the developing mammalian retina have been suggested as a potential source for the generation of high numbers of donor photoreceptors. In this study we used standardized culture conditions based on the presence of the mitogens FGF-2 and EGF to generate high numbers of cells in vitro from the developing mouse retina. These presumptive 'retinal stem cells' ('RSCs') can be propagated as monolayer cultures over multiple passages, express markers of undifferentiated neural cells, and generate neuronal and glial cell types upon withdrawal of mitogens in vitro or following transplantation into the adult mouse retina. The proportion of neuronal differentiation can be significantly increased by stepwise removal of mitogens and inhibition of the notch signaling pathway. However, 'RSCs', by contrast to their primary counterparts in vivo, i.e. retinal progenitor cells, loose the expression of retina-specific progenitor markers like Rax and Chx10 after passaging and fail to differentiate into photoreceptors both in vitro or after intraretinal transplantation. Notably, 'RSCs' can be induced to differentiate into myelinating oligodendrocytes, a cell type not generated by primary retinal progenitor cells. Based on these findings we conclude that 'RSCs' expanded in high concentrations of FGF-2 and EGF loose their retinal identity and acquire features of in vitro expandable neural stem-like cells making them an inappropriate cell source for strategies aimed at replacing photoreceptor cells in the degenerated retina.

  16. Over-expression of hNGF in adult human olfactory bulb neural stem cells promotes cell growth and oligodendrocytic differentiation.

    Directory of Open Access Journals (Sweden)

    Hany E S Marei

    precursor cells markers (PDGFRα, NG2 and CNPase respect to OBNS/PC-GFP counterparts. These findings suggest an enhanced proliferation and oligodendrocytic differentiation potential for OBNS/PC-GFP-hNGF as compared to OBNS/PC-GFP.

  17. Calcium receptor expression and function in oligodendrocyte commitment and lineage progression: potential impact on reduced myelin basic protein in CaR-null mice.

    Science.gov (United States)

    Chattopadhyay, Naibedya; Espinosa-Jeffrey, Araceli; Tfelt-Hansen, Jacob; Yano, Shozo; Bandyopadhyay, Sanghamitra; Brown, Edward M; de Vellis, Jean

    2008-08-01

    Oligodendrocytes develop from oligodendrocyte progenitor cells (OPCs), which in turn arise from a subset of neuroepithelial precursor cells during midneurogenesis. Development of the oligodendrocyte lineage involves a plethora of cell-intrinsic and -extrinsic signals. A cell surface calcium-sensing receptor (CaR) has been shown to be functionally expressed in immature oligodendrocytes. Here, we investigated the expression and function of the CaR during oligodendrocyte development. We show that the order of CaR mRNA expression as assessed by quantitative polymerase chain reaction is mature oligodendrocyte > neuron > astrocyte. We next determined the rank order of CaR expression on inducing specification of neural stem cells to the neuronal, oligodendroglial, or astrocytic lineages and found that the relative levels of CaR mRNA expression are OPC > neuron > astrocytes. CaR mRNA expression in cells at various stages of development along the oligodendrocyte lineage revealed that its expression is robustly up-regulated during the OPC stage and remains high until the premyelinating stage, decreasing thereafter by severalfold in the mature oligodendrocyte. In OPCs, high Ca(2+) acting via the CaR promotes cellular proliferation. We further observed that high Ca(2+) stimulates the mRNA levels of myelin basic protein in preoligodendrocytes, which is also CaR mediated. Finally, myelin basic protein levels were significantly reduced in the cerebellum of CaR-null mice during development. Our results show that CaR expression is up-regulated when neural stem cells are specified to the oligodendrocyte lineage and that activation of the receptor results in OPC expansion and differentiation. We conclude that the CaR may be a novel regulator of oligodendroglial development and function.

  18. PDGF-alpha receptor and myelin basic protein mRNAs are not coexpressed by oligodendrocytes in vivo: a double in situ hybridization study in the anterior medullary velum of the neonatal rat.

    Science.gov (United States)

    Butt, A M; Hornby, M F; Ibrahim, M; Kirvell, S; Graham, A; Berry, M

    1997-01-01

    Platelet-derived growth factor (PDGF) is a growth-regulatory dimer with A and B subunits. PDGF-AA, acting via PDGF receptors of the alpha-unit subtype (PDGF-alphaR), is implicated in the differentiation of oligodendrocyte precursors and in the survival of newly formed oligodendrocytes, which gradually lose expression of PDGF-alphaR. However, it is unclear whether terminally differentiated oligodendrocytes express PDGF-alphaR in vivo. To address this question, and to help clarify the role of PDGF-AA in late oligodendrocyte differentiation, we have used double in situ hybridization with digoxigenin- and fluorescein-labeled riboprobes to relate PDGF-alphaR mRNA and myelin basic protein (MBP) mRNA expression in the isolated intact anterior medullary velum (AMV) of rats ages Postnatal Day (P) 10-12 and P30-32. In parallel experiments, AMV were immunolabeled with the oligodendrocyte-specific monoclonal antibody Rip to provide information on oligodendrocyte development and the extent of myelination. At P10, the AMV contained tracts in which axons ranged from unmyelinated to fully myelinated, whereas myelination was complete in P30-32 AMV. The first oligodendrocytes to express MBP mRNA or Rip were promyelinating oligodendrocytes, which had a "star-burst" morphology and had not yet begun to form myelin sheaths. As myelination proceeded, MBP mRNA became dispersed throughout oligodendrocyte units, comprising cell somata, processes, and internodal myelin sheaths. By P30-32, MBP mRNA had been redistributed to the myelin sheaths only, reflecting a change in the site of protein synthesis in mature myelinated axon tracts. At no stage of oligodendrocyte differentiation did we observe cellular coexpression of mRNA for PDGFalphaR and MBP. Our results indicated that oligodendrocytes lost the expression of PDGFalphaR prior to gaining that of myelin gene products, and preclude an action of PDGF-AA on Rip+/MBP+ star-burst promyelinating oligodendrocytes. The spatial and temporal

  19. SOX2 expression is upregulated in adult spinal cord after contusion injury in both oligodendrocyte lineage and ependymal cells.

    Science.gov (United States)

    Lee, Hyun Joon; Wu, Junfang; Chung, Jumi; Wrathall, Jean R

    2013-02-01

    The upregulation of genes normally associated with development may occur in the adult after spinal cord injury (SCI). To test this, we performed real-time RT-PCR array analysis of mouse spinal cord mRNAs comparing embryonic day (E)14.5 spinal cord with intact adult and adult cord 1 week after a clinically relevant standardized contusion SCI. We found significantly increased expression of a large number of neural development- and stem cell-associated genes after SCI. These included Sox2 (sex determining region Y-box 2), a transcription factor that regulates self-renewal and potency of embryonic neural stem cells and is one of only a few key factors needed to induce pluripotency. In adult spinal cord of Sox2-EGFP mice, Sox2-EGFP was found mainly in the ependymal cells of the central canal. After SCI, both mRNA and protein levels of Sox2 were significantly increased at and near the injury site. By 1 day, Sox2 was upregulated in NG2(+) oligodendrocyte progenitor cells (OPC) in the spared white matter. By 3 days, Sox2-EGFP ependymal cells had increased proliferation and begun to form multiple layers and clusters of cells in the central lesion zone of the cord. Expression of Sox2 by NG2(+) cells had declined by 1 week, but increased numbers of other Sox2-expressing cells persisted for at least 4 weeks after SCI in both mouse and rat models. Thus, SCI upregulates many genes associated with development and neural stem cells, including the key transcription factor Sox2, which is expressed in a pool of cells that persists for weeks after SCI.

  20. Protective Effects of Berberine on Oxygen-Glucose Deprivation/Reperfusion on Oligodendrocyte Cell Line (OLN-93

    Directory of Open Access Journals (Sweden)

    Shabnam Nadjafi

    2014-01-01

    Conclusions: We concluded that berberine protected OLN-93 oligodendrocyte against ischemic induced excitotoxic injury. Attenuation of intracellular Ca 2+ overload by berberine may be the key mechanism that saved OLN-93 from excitotoxicity damage.

  1. Platelet-derived growth factor delays oligodendrocyte differentiation and axonal myelination in vivo in the anterior medullary velum of the developing rat.

    Science.gov (United States)

    Butt, A M; Hornby, M F; Kirvell, S; Berry, M

    1997-06-15

    The AA dimeric form of platelet-derived growth factor (PDGF-AA) is implicated in the differentiation of cells of the oligodendrocyte lineage, which express PDGF receptors of the alpha subunit type (PDGF-alphaR). In the present study, we show that a single injection of PDGF-AA into the cerebrospinal fluid of neonatal rats delays oligodendrocyte differentiation and interrupts the progress of myelination in the anterior medullary velum (AMV), a white matter tract roofing the IVth ventricle of the brain. PDGF-AA or saline was injected intrathecally in postnatal day (P) 7 rats, and the AMV was subsequently removed and immunolabelled with the oligodendrocyte-specific antibody Rip, at P9, P12, and P21, corresponding to postinjection days (PID) 2, 5, and 14. At P9 (PID2), myelination was retarded in PDGF-AA-treated rats as opposed to saline-treated controls but progressed rapidly after P12 (PID5). Quantification supported the qualitative observations that PDGF-AA mediated an acute decrease in the number of Rip+ oligodendrocytes at P9-12, which largely recovered by P21, suggesting that PDGF-AA may have delayed recruitment of myelinating oligodendrocytes. However, the definitive number of Rip+ oligodendrocytes in the AMV was not increased, suggesting that its action as a promoter of early oligodendrocyte survival may not ultimately affect the definitive number of myelinating oliogdendrocytes in vivo. We discuss the possibilities that excess PDGF-AA may have acted on early oligodendrocytes (precursors or preoligodendrocytes) to either (1) delay their differentiation by maintaining them in the cell cycle or (2) accelerate their differentiation, which may result in premature cell death in the absence of synchronised survival signals. This study supports a role for PDGF-AA in the timing of oligodendrocyte differentiation in vivo, as has been shown in vitro.

  2. Nestin Reporter Transgene Labels Multiple Central Nervous System Precursor Cells

    Directory of Open Access Journals (Sweden)

    Avery S. Walker

    2010-01-01

    Full Text Available Embryonic neuroepithelia and adult subventricular zone (SVZ stem and progenitor cells express nestin. We characterized a transgenic line that expresses enhanced green fluorescent protein (eGFP specified to neural tissue by the second intronic enhancer of the nestin promoter that had several novel features. During embryogenesis, the dorsal telencephalon contained many and the ventral telencephalon few eGFP+ cells. eGFP+ cells were found in postnatal and adult neurogenic regions. eGFP+ cells in the SVZ expressed multiple phenotype markers, glial fibrillary acidic protein, Dlx, and neuroblast-specific molecules suggesting the transgene is expressed through the lineage. eGFP+ cell numbers increased in the SVZ after cortical injury, suggesting this line will be useful in probing postinjury neurogenesis. In non-neurogenic regions, eGFP was strongly expressed in oligodendrocyte progenitors, but not in astrocytes, even when they were reactive. This eGFP+ mouse will facilitate studies of proliferative neuroepithelia and adult neurogenesis, as well as of parenchymal oligodendrocytes.

  3. Astrocytes induce proliferation of oligodendrocyte progenitor cells via connexin 47-mediated activation of the ERK/Id4 pathway.

    Science.gov (United States)

    Liu, Zhaoyu; Xu, Dan; Wang, Shang; Chen, Yi; Li, Zhen; Gao, Xiaoyan; Jiang, Lu; Tang, Yong; Peng, Yan

    2017-04-03

    The proliferative ability of oligodendrocyte progenitor cells (OPCs) varied markedly under different culture conditions. Astrocytes (ASTs) have been verified to play a major role in regulating the proliferation of OPCs through direct contact. However, the mechanisms have not been fully clarified. To investigate the effect and mechanism under AST and OPC co-culture conditions, we analyzed all connexins comprehensively in OPCs under OPC mono-culture, AST-secreted cell factor co-culture and AST-OPC direct-contact co-culture, and found that significantly differentially expressed Cx47 was the most significant. To assess whether Cx47 plays a role in proliferation, Cx47 siRNA were conducted. The result indicates that the cell cycle of OPCs was changed, and the cell proliferation was markedly inhibited. Kyoto Encyclopedia of Genes and Genomes (KEGG) predictive analysis suggested that Cx47 regulate cell cycle and proliferation by Ca(2+) activation of ERK1/2. To verify the prediction, flow cytometry, confocal microscopy, 5-ethynyl-2'-deoxyuridine (EdU), polymerase chain reaction (RT-PCR) and western blot were used. The results show that interference of Cx47 led to decreased Ca(2+) concentrations, lower p-ERK 1/2 levels, reduced transcription factor inhibitor of DNA binding 4 (Id4) expression, arrested cell cycle and reduced OPCs proliferative ability. Additionally, blocking ERK1/2 signaling caused decreased Id4 expression, arrested cell cycle in G1 phase, and reduced OPCs proliferative ability. In conclusion, ASTs can cause Ca(2+) signaling activation, ERK1/2 phosphorylation, and Id4 expression stimulation in OPCs, inducing proliferation of these cells, mainly through Cx47.

  4. A primitive cell origin for B-cell precursor ALL?

    Science.gov (United States)

    Cox, C V; Blair, A

    2005-01-01

    A stem cell origin has been described for both acute and chronic myelogenous leukemias. In contrast, childhood B-cell precursor acute lymphoblastic leukemia (ALL) is thought to arise in committed B-lineage cells. Recently described in vitro and in vivo model systems that support the proliferation and expansion of ALL cells have provided new tools to investigate the cellular targets for the origin of this malignancy. Evidence suggests that some subtypes of childhood ALL have a primitive cell origin and share many immunophenotypic characteristics with normal progenitor cells. These leukemic stem cells may be resistant to current therapeutic strategies designed to kill the bulk ALL cell population and subsequent relapses may arise from this population. More precise definition of these ALL stem cells through combined analyses of antigen expression, genetic lesions, and functionality is essential for the development of more effective, targeted therapeutic strategies.

  5. Development of neural precursor cells from mouse embryonic stem cells

    Institute of Scientific and Technical Information of China (English)

    WU Xuan; LI Hai-di; Li Shu-nong; XU Hai-wei; XU Ling

    2001-01-01

    Objective: To explore the serum-free culture conditions for differentiating mouse embryonic stem cells (ES cells)into neural precursor cells (NPC) and compare the effects of human embryonic fibroblasts (HEF) as the feeder layer of ES with that of mouse embryonic fibroblasts (MEF)in vitro. Methods: Mouse ES cells were cultured in or not in feeder layer cells medium containing or not leukemia inhibitory factor to suppress their differentiation. Immunocytochemical method was used to identify NPC by detecting nestin antigen and alkaline phosphatase. Results: The ES cells cultured in HEF were positive to alkaline phosphatase. Serum-free medium allowed the differentiation of ES cells into NPC. Conclusion:HEF could replace MEF and keep the undifferentiated condition of ES cells with more benefits. NPC of high purity could be cultured from ES cells by serum-free culture method.

  6. Therapeutic effect of transplanted human Wharton's jelly stem cell-derived oligodendrocyte progenitor cells (hWJ-MSC-derived OPCs) in an animal model of multiple sclerosis.

    Science.gov (United States)

    Mikaeili Agah, Elmira; Parivar, Kazem; Joghataei, Mohammad Taghi

    2014-04-01

    Multiple sclerosis (MS) is an immune-mediated demyelinating disease of the central nervous system (CNS). A potential new therapeutic approach for MS is cell transplantation which may promote remyelination. We transplanted human Wharton's jelly stem cell-derived oligodendrocyte progenitor cells (hWJ-MSC-derived OPCs) into the brain ventricles of mice induced with experimental autoimmune encephalomyelitis (EAE), the animal model of MS. We studied the effect of the transplanted OPCs on the functional and pathological manifestations of the disease. Transplanted hWJ-MSC-derived OPCs significantly reduced the clinical signs of EAE. Histological examinations showed that remyelination was significantly increased after transplantation. These results suggest that hWJ-MSC-derived OPCs promote the regeneration of myelin sheaths in the brain.

  7. Developmental stage of oligodendrocytes determines their response to activated microglia in vitro

    Directory of Open Access Journals (Sweden)

    Bresnahan Jacqueline C

    2007-11-01

    Full Text Available Abstract Background Oligodendrocyte progenitor cells (OPCs and mature oligodendrocytes are both lost in central nervous system injury and disease. Activated microglia may play a role in OPC and oligodendrocyte loss or replacement, but it is not clear how the responses of OPCs and oligodendrocytes to activated microglia differ. Methods OPCs and microglia were isolated from rat cortex. OPCs were induced to differentiate into oligodendrocytes with thyroid hormone in defined medium. For selected experiments, microglia were added to OPC or oligodendrocyte cultures. Lipopolysaccharide was used to activate microglia and microglial activation was confirmed by TNFα ELISA. Cell survival was assessed with immunocytochemistry and cell counts. OPC proliferation and oligodendrocyte apoptosis were also assessed. Results OPCs and oligodendrocytes displayed phenotypes representative of immature and mature oligodendrocytes, respectively. Activated microglia reduced OPC survival, but increased survival and reduced apoptosis of mature oligodendrocytes. Activated microglia also underwent cell death themselves. Conclusion Activated microglia may have divergent effects on OPCs and mature oligodendrocytes, reducing OPC survival and increasing mature oligodendrocyte survival. This may be of importance because activated microglia are present in several disease states where both OPCs and mature oligodendrocytes are also reacting to injury. Activated microglia may simultaneously have deleterious and helpful effects on different cells after central nervous system injury.

  8. Human embryonic epidermis contains a diverse Langerhans cell precursor pool.

    Science.gov (United States)

    Schuster, Christopher; Mildner, Michael; Mairhofer, Mario; Bauer, Wolfgang; Fiala, Christian; Prior, Marion; Eppel, Wolfgang; Kolbus, Andrea; Tschachler, Erwin; Stingl, Georg; Elbe-Bürger, Adelheid

    2014-02-01

    Despite intense efforts, the exact phenotype of the epidermal Langerhans cell (LC) precursors during human ontogeny has not been determined yet. These elusive precursors are believed to migrate into the embryonic skin and to express primitive surface markers, including CD36, but not typical LC markers such as CD1a, CD1c and CD207. The aim of this study was to further characterize the phenotype of LC precursors in human embryonic epidermis and to compare it with that of LCs in healthy adult skin. We found that epidermal leukocytes in first trimester human skin are negative for CD34 and heterogeneous with regard to the expression of CD1c, CD14 and CD36, thus contrasting the phenotypic uniformity of epidermal LCs in adult skin. These data indicate that LC precursors colonize the developing epidermis in an undifferentiated state, where they acquire the definitive LC marker profile with time. Using a human three-dimensional full-thickness skin model to mimic in vivo LC development, we found that FACS-sorted, CD207(-) cord blood-derived haematopoietic precursor cells resembling foetal LC precursors but not CD14(+)CD16(-) blood monocytes integrate into skin equivalents, and without additional exogenous cytokines give rise to cells that morphologically and phenotypically resemble LCs. Overall, it appears that CD14(-) haematopoietic precursors possess a much higher differentiation potential than CD14(+) precursor cells.

  9. Role of neural precursor cells in promoting repair following stroke

    Institute of Scientific and Technical Information of China (English)

    Pooya DIBAJNIA; Cindi M MORSHEAD

    2013-01-01

    Stem cell-based therapies for the treatment of stroke have received considerable attention.Two broad approaches to stem cell-based therapies have been taken:the transplantation of exogenous stem cells,and the activation of endogenous neural stem and progenitor cells (together termed neural precursors).Studies examining the transplantation of exogenous cells have demonstrated that neural stem and progenitor cells lead to the most clinically promising results.Endogenous activation of neural precursors has also been explored based on the fact that resident precursor cells have the inherent capacity to proliferate,migrate and differentiate into mature neurons in the uninjured adult brain.Studies have revealed that these neural precursor cell behaviours can be activated following stroke,whereby neural precursors will expand in number,migrate to the infarct site and differentiate into neurons.However,this innate response is insufficient to lead to functional recovery,making it necessary to enhance the activation of endogenous precursors to promote tissue repair and functional recovery.Herein we will discuss the current state of the stem cell-based approaches with a focus on endogenous repair to treat the stroke injured brain.

  10. UCB Transplant of Inherited Metabolic Diseases With Administration of Intrathecal UCB Derived Oligodendrocyte-Like Cells

    Science.gov (United States)

    2017-06-27

    Adrenoleukodystrophy; Batten Disease; Mucopolysaccharidosis II; Leukodystrophy, Globoid Cell; Leukodystrophy, Metachromatic; Neimann Pick Disease; Pelizaeus-Merzbacher Disease; Sandhoff Disease; Tay-Sachs Disease; Brain Diseases, Metabolic, Inborn; Alpha-Mannosidosis; Sanfilippo Mucopolysaccharidoses

  11. Altered Oligodendrocyte Maturation and Myelin Maintenance: The Role of Antiretrovirals in HIV-Associated Neurocognitive Disorders.

    Science.gov (United States)

    Jensen, Brigid K; Monnerie, Hubert; Mannell, Maggie V; Gannon, Patrick J; Espinoza, Cagla Akay; Erickson, Michelle A; Bruce-Keller, Annadora J; Gelman, Benjamin B; Briand, Lisa A; Pierce, R Christopher; Jordan-Sciutto, Kelly L; Grinspan, Judith B

    2015-11-01

    Despite effective viral suppression through combined antiretroviral therapy (cART), approximately half of HIV-positive individuals have HIV-associated neurocognitive disorders (HAND). Studies of antiretroviral-treated patients have revealed persistent white matter abnormalities including diffuse myelin pallor, diminished white matter tracts, and decreased myelin protein mRNAs. Loss of myelin can contribute to neurocognitive dysfunction because the myelin membrane generated by oligodendrocytes is essential for rapid signal transduction and axonal maintenance. We hypothesized that myelin changes in HAND are partly due to effects of antiretroviral drugs on oligodendrocyte survival and/or maturation. We showed that primary mouse oligodendrocyte precursor cell cultures treated with therapeutic concentrations of HIV protease inhibitors ritonavir or lopinavir displayed dose-dependent decreases in oligodendrocyte maturation; however, this effect was rapidly reversed after drug removal. Conversely, nucleoside reverse transcriptase inhibitor zidovudine had no effect. Furthermore, in vivo ritonavir administration to adult mice reduced frontal cortex myelin protein levels. Finally, prefrontal cortex tissue from HIV-positive individuals with HAND on cART showed a significant decrease in myelin basic protein compared with untreated HIV-positive individuals with HAND or HIV-negative controls. These findings demonstrate that antiretrovirals can impact myelin integrity and have implications for myelination in juvenile HIV patients and myelin maintenance in adults on lifelong therapy.

  12. Brain-derived neurotrophic factor promotes central nervous system myelination via a direct effect upon oligodendrocytes.

    Science.gov (United States)

    Xiao, Junhua; Wong, Agnes W; Willingham, Melanie M; van den Buuse, Maarten; Kilpatrick, Trevor J; Murray, Simon S

    2010-01-01

    The extracellular factors that are responsible for inducing myelination in the central nervous system (CNS) remain elusive. We investigated whether brain-derived neurotrophic factor (BDNF) is implicated, by first confirming that BDNF heterozygous mice exhibit delayed CNS myelination during early postnatal development. We next established that the influence of BDNF upon myelination was direct, by acting on oligodendrocytes, using co-cultures of dorsal root ganglia neurons and oligodendrocyte precursor cells. Importantly, we found that BDNF retains its capacity to enhance myelination of neurons or by oligodendrocytes derived from p75NTR knockout mice, indicating the expression of p75NTR is not necessary for BDNF-induced myelination. Conversely, we observed that phosphorylation of TrkB correlated with myelination, and that inhibiting TrkB signalling also inhibited the promyelinating effect of BDNF, suggesting that BDNF enhances CNS myelination via activating oligodendroglial TrkB-FL receptors. Together, our data reveal a previously unknown role for BDNF in potentiating the normal development of CNS myelination, via signalling within oligodendrocytes.

  13. Downregulation of the microtubule associated protein tau impairs process outgrowth and myelin basic protein mRNA transport in oligodendrocytes.

    Science.gov (United States)

    Seiberlich, Veronika; Bauer, Nina G; Schwarz, Lisa; Ffrench-Constant, Charles; Goldbaum, Olaf; Richter-Landsberg, Christiane

    2015-09-01

    Oligodendrocytes, the myelin forming cells of the CNS, are characterized by their numerous membranous extensions, which enwrap neuronal axons and form myelin sheaths. During differentiation oligodendrocytes pass different morphological stages, downregulate the expression of the proteoglycan NG2, and acquire major myelin specific proteins, such as myelin basic proteins (MBP) and proteolipid protein. MBP mRNA is transported in RNA granules along the microtubules (MTs) to the periphery and translated locally. MTs participate in the elaboration and stabilization of the myelin forming extensions and are essential for cellular sorting processes. Their dynamic properties are regulated by microtubule associated proteins (MAPs). The MAP tau is present in oligodendrocytes and involved in the regulation and stabilization of the MT network. To further elucidate the functional significance of tau in oligodendrocytes, we have downregulated tau by siRNA technology and studied the effects on cell differentiation and neuron-glia contact formation. The data show that tau knockdown impairs process outgrowth and leads to a decrease in MBP expression. Furthermore, MBP mRNA transport to distant cellular extensions is impaired and cells remain in the NG2 stage. In myelinating cocultures with dorsal root ganglion neurons, oligodendrocyte precursor cells after tau miR RNA lentiviral knockdown develop into NG2 positive cells with very long and thin processes, contacting axons loosely, but fail to form internodes. This demonstrates that tau is important for MBP mRNA transport and involved in process formation. The disturbance of the balance of tau leads to abnormalities in oligodendrocyte differentiation, neuron-glia contact formation and the early myelination process.

  14. E2F1 Coregulates Cell Cycle Genes and Chromatin Components during the Transition of Oligodendrocyte Progenitors from Proliferation to Differentiation

    Science.gov (United States)

    Magri, Laura; Swiss, Victoria A.; Jablonska, Beata; Lei, Liang; Pedre, Xiomara; Walsh, Martin; Zhang, Weijia; Gallo, Vittorio; Canoll, Peter

    2014-01-01

    Cell cycle exit is an obligatory step for the differentiation of oligodendrocyte progenitor cells (OPCs) into myelinating cells. A key regulator of the transition from proliferation to quiescence is the E2F/Rb pathway, whose activity is highly regulated in physiological conditions and deregulated in tumors. In this paper we report a lineage-specific decline of nuclear E2F1 during differentiation of rodent OPC into oligodendrocytes (OLs) in developing white matter tracts and in cultured cells. Using chromatin immunoprecipitation (ChIP) and deep-sequencing in mouse and rat OPCs, we identified cell cycle genes (i.e., Cdc2) and chromatin components (i.e., Hmgn1, Hmgn2), including those modulating DNA methylation (i.e., Uhrf1), as E2F1 targets. Binding of E2F1 to chromatin on the gene targets was validated and their expression assessed in developing white matter tracts and cultured OPCs. Increased expression of E2F1 gene targets was also detected in mouse gliomas (that were induced by retroviral transformation of OPCs) compared with normal brain. Together, these data identify E2F1 as a key transcription factor modulating the expression of chromatin components in OPC during the transition from proliferation to differentiation. PMID:24453336

  15. Shh Signaling through the Primary Cilium Modulates Rat Oligodendrocyte Differentiation.

    Science.gov (United States)

    Falcón-Urrutia, Paulina; Carrasco, Carlos M; Lois, Pablo; Palma, Veronica; Roth, Alejandro D

    2015-01-01

    Primary Cilia (PC) are a very likely place for signal integration where multiple signaling pathways converge. Two major signaling pathways clearly shown to signal through the PC, Sonic Hedgehog (Shh) and PDGF-Rα, are particularly important for the proliferation and differentiation of oligodendrocytes, suggesting that their interaction occurs in or around this organelle. We identified PC in rat oligodendrocyte precursor cells (OPCs) and found that, while easily detectable in early OPCs, PC are lost as these cells progress to terminal differentiation. We confirmed the interaction between these pathways, as cyclopamine inhibition of Hedgehog function impairs both PDGF-mediated OPC proliferation and Shh-dependent cell branching. However, we failed to detect PDGF-Rα localization into the PC. Remarkably, ciliobrevin-mediated disruption of PC and reduction of OPC process extension was counteracted by recombinant Shh treatment, while PDGF had no effect. Therefore, while PDGF-Rα-dependent OPC proliferation and survival most probably does not initiate at the PC, still the integrity of this organelle and cilium-centered pathway is necessary for OPC survival and differentiation.

  16. Oligodendrocyte dysfunction in the pathogenesis of amyotrophic lateral sclerosis

    NARCIS (Netherlands)

    Philips, T.; Bento-Abreu, A.; Nonneman, A.; Haeck, W.; Staats, K.; Geelen, V.; Hersmus, N.; Kusters, B.; Bosch, L. Van Den; Damme, P. van; Richardson, W.D.; Robberecht, W.

    2013-01-01

    Oligodendrocytes are well known targets for immune-mediated and infectious diseases, and have been suggested to play a role in neurodegeneration. Here, we report the involvement of oligodendrocytes and their progenitor cells in the ventral grey matter of the spinal cord in amyotrophic lateral sclero

  17. Oligodendrocyte dysfunction in the pathogenesis of amyotrophic lateral sclerosis

    NARCIS (Netherlands)

    Philips, T.; Bento-Abreu, A.; Nonneman, A.; Haeck, W.; Staats, K.; Geelen, V.; Hersmus, N.; Kusters, B.; Bosch, L. Van Den; Damme, P. van; Richardson, W.D.; Robberecht, W.

    2013-01-01

    Oligodendrocytes are well known targets for immune-mediated and infectious diseases, and have been suggested to play a role in neurodegeneration. Here, we report the involvement of oligodendrocytes and their progenitor cells in the ventral grey matter of the spinal cord in amyotrophic lateral sclero

  18. 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

  19. 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.

  20. An Extract of Chinpi, the Dried Peel of the Citrus Fruit Unshiu, Enhances Axonal Remyelination via Promoting the Proliferation of Oligodendrocyte Progenitor Cells

    Directory of Open Access Journals (Sweden)

    Hideaki Tokunaga

    2016-01-01

    Full Text Available The aging-induced decrease in axonal myelination/remyelination is due to impaired recruitment and differentiation of oligodendrocyte progenitor cells (OPCs. Our previous studies have shown that a monoclonal antibody to DEAD (Asp-Glu-Ala-Asp box polypeptide 54 (Ddx54, a member of the DEAD box family of RNA helicases, (1 specifically labels oligodendrocyte lineages, (2 binds to mRNA and protein isoforms of myelin basic proteins (MBP, and (3 regulates migration of OPCs from ventricular zone to corpus callosum in mice. It has also been demonstrated that specific loss of a 21.5 kDa MBP isoform (MBP21.5 reflects demyelination status, and oral administration of an extract of Chinpi, citrus unshiu peel, reversed the aging-induced demyelination. Here, we report that Chinpi treatment induced a specific increase in the MBP21.5, led to the reappearance of Ddx54-expressing cells in ventricular-subventricular zone and corpus callosum of aged mice, and promoted remyelination. Treatment of in vitro OPC cultures with Chinpi constituents, hesperidin plus narirutin, led to an increase in 5-bromo-2′-deoxyuridine incorporation in Ddx54-expressing OPCs, but not in NG2- or Olig2-expressing cell populations. The present study suggests that Ddx54 plays crucial role in remyelination. Furthermore, Chinpi and Chinpi-containing herbal medicines may be a therapeutic option for the aging-induced demyelination diseases.

  1. Resistance of subventricular neural stem cells to chronic hypoxemia despite structural disorganization of the germinal center and impairment of neuronal and oligodendrocyte survival

    Science.gov (United States)

    d’Anglemont de Tassigny, Xavier; Sirerol-Piquer, M Salomé; Gómez-Pinedo, Ulises; Pardal, Ricardo; Bonilla, Sonia; Capilla-Gonzalez, Vivian; López-López, Ivette; De la Torre-Laviana, Francisco Javier; García-Verdugo, José Manuel; López-Barneo, José

    2015-01-01

    Chronic hypoxemia, as evidenced in de-acclimatized high-altitude residents or in patients with chronic obstructive respiratory disorders, is a common medical condition that can produce serious neurological alterations. However, the pathogenesis of this phenomenon is unknown. We have found that adult rodents exposed for several days/weeks to hypoxia, with an arterial oxygen tension similar to that of chronically hypoxemic patients, manifest a partially irreversible structural disarrangement of the subventricular neurogenic niche (subventricular zone) characterized by displacement of neurons and myelinated axons, flattening of the ependymal cell layer, and thinning of capillary walls. Despite these abnormalities, the number of neuronal and oligodendrocyte progenitors, neuroblasts, and neurosphere-forming cells as well as the proliferative activity in subventricular zone was unchanged. These results suggest that neural stem cells and their undifferentiated progeny are resistant to hypoxia. However, in vivo and in vitro experiments indicate that severe chronic hypoxia decreases the survival of newly generated neurons and oligodendrocytes, with damage of myelin sheaths. These findings help explain the effects of hypoxia on adult neurogenesis and provide new perspectives on brain responsiveness to persistent hypoxemia. PMID:27774479

  2. Laser microdissection of sensory organ precursor cells of Drosophila microchaetes.

    Directory of Open Access Journals (Sweden)

    Eulalie Buffin

    Full Text Available BACKGROUND: In Drosophila, each external sensory organ originates from the division of a unique precursor cell (the sensory organ precursor cell or SOP. Each SOP is specified from a cluster of equivalent cells, called a proneural cluster, all of them competent to become SOP. Although, it is well known how SOP cells are selected from proneural clusters, little is known about the downstream genes that are regulated during SOP fate specification. METHODOLOGY/PRINCIPAL FINDINGS: In order to better understand the mechanism involved in the specification of these precursor cells, we combined laser microdissection, toisolate SOP cells, with transcriptome analysis, to study their RNA profile. Using this procedure, we found that genes that exhibit a 2-fold or greater expression in SOPs versus epithelial cells were mainly associated with Gene Ontology (GO terms related with cell fate determination and sensory organ specification. Furthermore, we found that several genes such as pebbled/hindsight, scabrous, miranda, senseless, or cut, known to be expressed in SOP cells by independent procedures, are particularly detected in laser microdissected SOP cells rather than in epithelial cells. CONCLUSIONS/SIGNIFICANCE: These results confirm the feasibility and the specificity of our laser microdissection based procedure. We anticipate that this analysis will give new insight into the selection and specification of neural precursor cells.

  3. NG2-expressing glial precursor cells are a new potential oligodendroglioma cell initiating population in N-ethyl-N-nitrosourea-induced gliomagenesis.

    Science.gov (United States)

    Briançon-Marjollet, Anne; Balenci, Laurent; Fernandez, Manuel; Estève, François; Honnorat, Jérôme; Farion, Régine; Beaumont, Marine; Barbier, Emmanuel; Rémy, Chantal; Baudier, Jacques

    2010-10-01

    Gliomas are the most common primary brain tumor affecting human adults and remain a therapeutic challenge because cells of origin are still unknown. Here, we investigated the cellular origin of low-grade gliomas in a rat model based on transplacental exposure to N-ethyl-N-nitrosourea (ENU). Longitudinal magnetic resonance imaging coupled to immunohistological and immunocytochemical analyses were used to further characterize low-grade rat gliomas at different stages of evolution. We showed that early low-grade gliomas have characteristics of oligodendroglioma-like tumors and exclusively contain NG2-expressing slow dividing precursor cells, which express early markers of oligodendroglial lineage. These tumor-derived precursors failed to fully differentiate into oligodendrocytes and exhibited multipotential abilities in vitro. Moreover, a few glioma NG2+ cells are resistant to radiotherapy and may be responsible for tumor recurrence, frequently observed in humans. Overall, these findings suggest that transformed multipotent NG2 glial precursor cell may be a potential cell of origin in the genesis of rat ENU-induced oligodendroglioma-like tumors. This work may open up new perspectives for understanding biology of human gliomas.

  4. Quantification of erythroid and granulocytic precursor cells in plateletpheresis residues

    Energy Technology Data Exchange (ETDEWEB)

    Abboud, C.N.; Brennan, J.K.; Lichtman, M.A.; Nusbacher, J.

    1978-01-01

    Mononuclear cell fractions of human blood and plateletpheresis residues were compared for their content of hemopoietic precursor cells. Erythroid burst-forming units (BFU-E) averaged 560 +- 130 per ml of blood and granulocyte--monocyte colony forming units (CFU-C) averaged 240 +- 90 per ml blood. Estimates based on a blood volume of 7% of body weight indicate that the total blood pools of BFU-E and CFU-C are about 3.5 x 10/sup 6/ and 1.5 x 10/sup 6/ cells respectively. Sequential studies were performed over 3 days following one plateletpheresis in 4 donors. CFU-C and BFU-E approximately doubled between 48 and 72 hours after a plateletpheresis. During this time there was no significant alteration in the percent of null, T or B lymphocytes in blood. Thus, plateletpheresis appears to lead to a mobilization of precursor cells, which results in a transient increase in their concentration in blood. Therefore, pheresis 48 to 72 hours after an initial short-term procedure could harvest much larger numbers of precursor cells. Moreover, such techniques would put blood precursor cell content of plateletpheresis residues within reach of the precursor cell content in the volume of human marrow used for transplantation.

  5. Cerebrospinal fluid derived from progressive multiple sclerosis patients promotes neuronal and oligodendroglial differentiation of human neural precursor cells in vitro.

    Science.gov (United States)

    Cristofanilli, M; Cymring, B; Lu, A; Rosenthal, H; Sadiq, S A

    2013-10-10

    In the adult CNS, tissue-specific germinal niches, such as the subventricular zone of the lateral ventricles and the subgranular zone of the dentate gyrus of the hippocampus, contain multipotent neural precursor cells (NPCs) with the capacity to self-renew and differentiate into functional brain cells (i.e. neurons, astrocytes or oligodendrocytes). Due to their intrinsic plasticity, NPCs can be considered an essential part of the cellular mechanism(s) by which the CNS tries to repair itself after an injury. In inflammatory CNS disorders, such as multiple sclerosis (MS), neurogenesis and gliogenesis occur as part of an 'intrinsic' self-repair process. However, full and long-lasting repair in progressive MS is not achieved. Recent data suggest that endogenous NPCs, while trying to repair the damaged CNS in MS, may become the target of the disease itself. It is possible that factors produced during MS, like CNS-infiltrating blood-borne inflammatory mononuclear cells, reactive CNS-resident cells, and humoral mediators, can alter the physiological properties of NPCs, ultimately impairing their ability to promote neural regeneration. Here, we investigate the effect of cerebrospinal fluid (CSF) derived from primary progressive (PPMS) and secondary progressive (SPMS) MS patients (CSF-MS) on the survival, proliferation, and differentiation of commercially available human embryonic-derived NPCs named ENStem-A. We found that PPMS derived CSF markedly reduced the proliferation of ENStem-A and increased their differentiation toward neuronal and oligodendroglial cells, compared to control CSF. Similar but less striking results were seen when ENstem-A were treated with SPMS derived CSF. Our findings suggest that in both SPMS and PPMS the CNS milieu, as determined by extrapolation from CSF findings, may stimulate the endogenous pool of NPCs to differentiate into neurons and oligodendrocytes.

  6. Synthesis of gangliosides by cultured oligodendrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Mack, S.R.; Szuchet, S.; Dawson, G.

    1981-01-01

    Gangliosides are enriched in the nervous system compared to other tissues. The synthesis of gangliosides by monolayer cultures of isolated oligodendrocytes has not previously been investigated. Cells were labeled with (3H) galactose at preselected times and gangliosides isolated by phase partition, purified, and identified by chromatography. Cultured oligodendrocytes showed selectivity in their synthesis of gangliosides, which was expressed in the type of ganglioside synthesized as well as in the change of incorporation over time in culture. For the first ten days, there was very little incorporation of (3H) galactose in gangliosides, but this was followed by a stimulation of uptake for GM3, GM1/GD3, and GD1 gangliosides, reaching a maximum after approximately 25-30 days in vitro. There was little incorporation into GM2 or trisialogangliosides throughout the life of the cultures. Since oligodendrocytes synthesize extensive membranes during this period, one may speculate that the de novo-synthesized gangliosides are used for membranes.

  7. Culture of Mouse Neural Stem Cell Precursors

    OpenAIRE

    Currle, D. Spencer; Hu, Jia Sheng; Kolski-Andreaco, Aaron; Monuki, Edwin S

    2007-01-01

    Primary neural stem cell cultures are useful for studying the mechanisms underlying central nervous system development. Stem cell research will increase our understanding of the nervous system and may allow us to develop treatments for currently incurable brain diseases and injuries. In addition, stem cells should be used for stem cell research aimed at the detailed study of mechanisms of neural differentiation and transdifferentiation and the genetic and environmental signals that direct the...

  8. Therapeutic activities of engrafted neural stem/precursor cells are not dormant in the chronically injured spinal cord.

    Science.gov (United States)

    Kumamaru, Hiromi; Saiwai, Hirokazu; Kubota, Kensuke; Kobayakawa, Kazu; Yokota, Kazuya; Ohkawa, Yasuyuki; Shiba, Keiichiro; Iwamoto, Yukihide; Okada, Seiji

    2013-08-01

    The transplantation of neural stem/precursor cells (NSPCs) is a promising therapeutic strategy for many neurodegenerative disorders including spinal cord injury (SCI) because it provides for neural replacement or trophic support. This strategy is now being extended to the treatment of chronic SCI patients. However, understanding of biological properties of chronically transplanted NSPCs and their surrounding environments is limited. Here, we performed temporal analysis of injured spinal cords and demonstrated their multiphasic cellular and molecular responses. In particular, chronically injured spinal cords were growth factor-enriched environments, whereas acutely injured spinal cords were enriched by neurotrophic and inflammatory factors. To determine how these environmental differences affect engrafted cells, NSPCs transplanted into acutely, subacutely, and chronically injured spinal cords were selectively isolated by flow cytometry, and their whole transcriptomes were compared by RNA sequencing. This analysis revealed that NSPCs produced many regenerative/neurotrophic molecules irrespective of transplantation timing, and these activities were prominent in chronically transplanted NSPCs. Furthermore, chronically injured spinal cords permitted engrafted NSPCs to differentiate into neurons/oligodendrocytes and provided more neurogenic environment for NSPCs than other environments. Despite these results demonstrate that transplanted NSPCs have adequate capacity in generating neurons/oligodendrocytes and producing therapeutic molecules in chronic SCI microenvironments, they did not improve locomotor function. Our results indicate that failure in chronic transplantation is not due to the lack of therapeutic activities of engrafted NSPCs but the refractory state of chronically injured spinal cords. Environmental modulation, rather modification of transplanting cells, will be significant for successful translation of stem cell-based therapies into chronic SCI patients.

  9. Subclasses of oligodendrocytes populate the mouse hippocampus

    NARCIS (Netherlands)

    Vinet, Jonathan; Lemieux, Philippe; Tamburri, Albert; Tiesinga, Paul; Scafidi, Joseph; Gallo, Vittorio; Sik, Attila

    2010-01-01

    Oligodendrocytes are the myelin-forming cells of the central nervous system that facilitate transmission of axonal electrical impulses. Using transgenic mice expressing 2',3' cyclic nucleotide 3' phosphodiesterase (CNPase)-enhanced green fluorescent protein, a three-dimensional reconstruction tool a

  10. Derivation of multipotent mesenchymal precursors from human embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    2005-06-01

    Full Text Available BACKGROUND: Human embryonic stem cells provide access to the earliest stages of human development and may serve as a source of specialized cells for regenerative medicine. Thus, it becomes crucial to develop protocols for the directed differentiation of embryonic stem cells into tissue-restricted precursors. METHODS AND FINDINGS: Here, we present culture conditions for the derivation of unlimited numbers of pure mesenchymal precursors from human embryonic stem cells and demonstrate multilineage differentiation into fat, cartilage, bone, and skeletal muscle cells. CONCLUSION: Our findings will help to elucidate the mechanism of mesoderm specification during embryonic stem cell differentiation and provide a platform to efficiently generate specialized human mesenchymal cell types for future clinical applications.

  11. Biochemical subtypes of oligodendrocyte in the anterior medullary velum of the rat as revealed by the monoclonal antibody Rip.

    Science.gov (United States)

    Butt, A M; Ibrahim, M; Ruge, F M; Berry, M

    1995-07-01

    Oligodendrocytes were studied in the anterior medullary velum (AMV) of the rat using the monoclonal antibody Rip, an oligodendrocyte marker of unknown function. Confocal microscopic imaging of double immunofluorescent labelling with antibodies to Rip and carbonic anhydrase II (CAII) revealed two biochemically and morphologically distinct populations of oligodendrocyte which were either Rip+CAII+ or Rip+CAII-. Double immunofluorescent labelling with Rip and myelin basic protein (MBP) or glial fibrillary acidic protein (GFAP) provided direct evidence that Rip-labelled cells were phenotypically oligodendrocytes and confirmed that Rip did not recognise astrocytes. Oligodendrocytes which were Rip+CAII+ supported numerous myelin sheaths for small diameter axons, whilst Rip+CAII- oligodendrocytes supported fewer myelin sheaths for large diameter axons. Morphologically, Rip+CAII+ oligodendrocytes corresponded to types I or II of classical nomenclature, whilst Rip+CAII- oligodendrocytes corresponded to types III and IV. The results demonstrated a biochemical difference between oligodendrocytes which myelinated small and large diameter fibres.

  12. Injectable hydrogel promotes early survival of induced pluripotent stem cell-derived oligodendrocytes and attenuates longterm teratoma formation in a spinal cord injury model.

    Science.gov (United States)

    Führmann, T; Tam, R Y; Ballarin, B; Coles, B; Elliott Donaghue, I; van der Kooy, D; Nagy, A; Tator, C H; Morshead, C M; Shoichet, M S

    2016-03-01

    Transplantation of pluripotent stem cells and their differentiated progeny has the potential to preserve or regenerate functional pathways and improve function after central nervous system injury. However, their utility has been hampered by poor survival and the potential to form tumors. Peptide-modified biomaterials influence cell adhesion, survival and differentiation in vitro, but their effectiveness in vivo remains uncertain. We synthesized a peptide-modified, minimally invasive, injectable hydrogel comprised of hyaluronan and methylcellulose to enhance the survival and differentiation of human induced pluripotent stem cell-derived oligodendrocyte progenitor cells. Cells were transplanted subacutely after a moderate clip compression rat spinal cord injury. The hydrogel, modified with the RGD peptide and platelet-derived growth factor (PDGF-A), promoted early survival and integration of grafted cells. However, prolific teratoma formation was evident when cells were transplanted in media at longer survival times, indicating that either this cell line or the way in which it was cultured is unsuitable for human use. Interestingly, teratoma formation was attenuated when cells were transplanted in the hydrogel, where most cells differentiated to a glial phenotype. Thus, this hydrogel promoted cell survival and integration, and attenuated teratoma formation by promoting cell differentiation.

  13. mTOR: a link from the extracellular milieu to transcriptional regulation of oligodendrocyte development

    Directory of Open Access Journals (Sweden)

    Teresa L. Wood

    2013-03-01

    Full Text Available Oligodendrocyte development is controlled by numerous extracellular signals that regulate a series of transcription factors that promote the differentiation of oligodendrocyte progenitor cells to myelinating cells in the central nervous system. A major element of this regulatory system that has only recently been studied is the intracellular signalling from surface receptors to transcription factors to down-regulate inhibitors and up-regulate inducers of oligodendrocyte differentiation and myelination. The current review focuses on one such pathway: the mTOR (mammalian target of rapamycin pathway, which integrates signals in many cell systems and induces cell responses including cell proliferation and cell differentiation. This review describes the known functions of mTOR as they relate to oligodendrocyte development, and its recently discovered impact on oligodendrocyte differentiation and myelination. A potential model for its role in oligodendrocyte development is proposed.

  14. mTOR: A Link from the Extracellular Milieu to Transcriptional Regulation of Oligodendrocyte Development

    Directory of Open Access Journals (Sweden)

    Teresa L. Wood

    2013-02-01

    Full Text Available Oligodendrocyte development is controlled by numerous extracellular signals that regulate a series of transcription factors that promote the differentiation of oligodendrocyte progenitor cells to myelinating cells in the central nervous system. A major element of this regulatory system that has only recently been studied is the intracellular signalling from surface receptors to transcription factors to down-regulate inhibitors and up-regulate inducers of oligodendrocyte differentiation and myelination. The current review focuses on one such pathway: the mTOR (mammalian target of rapamycin pathway, which integrates signals in many cell systems and induces cell responses including cell proliferation and cell differentiation. This review describes the known functions of mTOR as they relate to oligodendrocyte development, and its recently discovered impact on oligodendrocyte differentiation and myelination. A potential model for its role in oligodendrocyte development is proposed.

  15. Targeted Overexpression of a Golli-Myelin Basic Protein Isoform to Oligodendrocytes Results in Aberrant Oligodendrocyte Maturation and Myelination

    Directory of Open Access Journals (Sweden)

    Erin C Jacobs

    2009-08-01

    Full Text Available Recently, several in vitro studies have shown that the golli-myelin basic proteins regulate Ca2+ homoeostasis in OPCs (oligodendrocyte precursor cells and immature OLs (oligodendrocytes, and that a number of the functions of these cells are affected by cellular levels of the golli proteins. To determine the influence of golli in vivo on OL development and myelination, a transgenic mouse was generated in which the golli isoform J37 was overexpressed specifically within OLs and OPCs. The mouse, called JOE (J37-overexpressing, is severely hypomyelinated between birth and postnatal day 50. During this time, it exhibits severe intention tremors that gradually abate at later ages. After postnatal day 50, ultrastructural studies and Northern and Western blot analyses indicate that myelin accumulates in the brain, but never reaches normal levels. Several factors appear to underlie the extensive hypomyelination. In vitro and in vivo experiments indicate that golli overexpression causes a significant delay in OL maturation, with accumulation of significantly greater numbers of pre-myelinating OLs that fail to myelinate axons during the normal myelinating period. Immunohistochemical studies with cell death and myelin markers indicate that JOE OLs undergo a heightened and extended period of cell death and are unable to effectively myelinate until 2 months after birth. The results indicate that increased levels of golli in OPC/OLs delays myelination, causing significant cell death of OLs particularly in white matter tracts. The results provide in vivo evidence for a significant role of the golli proteins in the regulation of maturation of OLs and normal myelination.

  16. Stimulation of adult oligodendrogenesis by myelin-specific T cells

    DEFF Research Database (Denmark)

    Hvilsted Nielsen, Helle; Toft-Hansen, Henrik; Lambertsen, Kate Lykke

    2011-01-01

    investigated the effect of myelin-specific T cells on oligodendrocyte formation at sites of axonal damage in the mouse hippocampal dentate gyrus. Infiltrating T cells specific for myelin proteolipid protein stimulated proliferation of chondroitin sulfate NG2-expressing oligodendrocyte precursor cells early...... of calretinergic associational/commissural fibers within the dentate gyrus. These results have implications for the perception of MS pathogenesis because they show that infiltrating myelin-specific T cells can stimulate oligodendrogenesis in the adult central nervous system....

  17. LINGO-1, a transmembrane signaling protein, inhibits oligodendrocyte differentiation and myelination through intercellular self-interactions.

    Science.gov (United States)

    Jepson, Scott; Vought, Bryan; Gross, Christian H; Gan, Lu; Austen, Douglas; Frantz, J Daniel; Zwahlen, Jacque; Lowe, Derek; Markland, William; Krauss, Raul

    2012-06-22

    Overcoming remyelination failure is a major goal of new therapies for demyelinating diseases like multiple sclerosis. LINGO-1, a key negative regulator of myelination, is a transmembrane signaling protein expressed in both neurons and oligodendrocytes. In neurons, LINGO-1 is an integral component of the Nogo receptor complex, which inhibits axonal growth via RhoA. Because the only ligand-binding subunit of this complex, the Nogo receptor, is absent in oligodendrocytes, the extracellular signals that inhibit myelination through a LINGO-1-mediated mechanism are unknown. Here we show that LINGO-1 inhibits oligodendrocyte terminal differentiation through intercellular interactions and is capable of a self-association in trans. Consistent with previous reports, overexpression of full-length LINGO-1 inhibited differentiation of oligodendrocyte precursor cells (OPCs). Unexpectedly, treatment with a soluble recombinant LINGO-1 ectodomain also had an inhibitory effect on OPCs and decreased myelinated axonal segments in cocultures with neurons from dorsal root ganglia. We demonstrated LINGO-1-mediated inhibition of OPCs through intercellular signaling by using a surface-bound LINGO-1 construct expressed ectopically in astrocytes. Further investigation showed that the soluble LINGO-1 ectodomain can interact with itself in trans by binding to CHO cells expressing full-length LINGO-1. Finally, we observed that soluble LINGO-1 could activate RhoA in OPCs. We propose that LINGO-1 acts as both a ligand and a receptor and that the mechanism by which it negatively regulates OPC differentiation and myelination is mediated by a homophilic intercellular interaction. Disruption of this protein-protein interaction could lead to a decrease of LINGO-1 inhibition and an increase in myelination.

  18. Neuroprotective effect of transplanted human embryonic stem cell-derived neural precursors in an animal model of multiple sclerosis.

    Directory of Open Access Journals (Sweden)

    Michal Aharonowiz

    Full Text Available BACKGROUND: Multiple sclerosis (MS is an immune mediated demyelinating disease of the central nervous system (CNS. A potential new therapeutic approach for MS is cell transplantation which may promote remyelination and suppress the inflammatory process. METHODS: We transplanted human embryonic stem cells (hESC-derived early multipotent neural precursors (NPs into the brain ventricles of mice induced with experimental autoimmune encephalomyelitis (EAE, the animal model of MS. We studied the effect of the transplanted NPs on the functional and pathological manifestations of the disease. RESULTS: Transplanted hESC-derived NPs significantly reduced the clinical signs of EAE. Histological examination showed migration of the transplanted NPs to the host white matter, however, differentiation to mature oligodendrocytes and remyelination were negligible. Time course analysis of the evolution and progression of CNS inflammation and tissue injury showed an attenuation of the inflammatory process in transplanted animals, which was correlated with the reduction of both axonal damage and demyelination. Co-culture experiments showed that hESC-derived NPs inhibited the activation and proliferation of lymph node-derived T cells in response to nonspecific polyclonal stimuli. CONCLUSIONS: The therapeutic effect of transplantation was not related to graft or host remyelination but was mediated by an immunosuppressive neuroprotective mechanism. The attenuation of EAE by hESC-derived NPs, demonstrated here, may serve as the first step towards further developments of hESC for cell therapy in MS.

  19. Oligodendroglial p130Cas is a target of Fyn kinase involved in process formation, cell migration and survival.

    Directory of Open Access Journals (Sweden)

    Constantin Gonsior

    Full Text Available Oligodendrocytes are the myelinating glial cells of the central nervous system. In the course of brain development, oligodendrocyte precursor cells migrate, scan the environment and differentiate into mature oligodendrocytes with multiple cellular processes which recognize and ensheath neuronal axons. During differentiation, oligodendrocytes undergo dramatic morphological changes requiring cytoskeletal rearrangements which need to be tightly regulated. The non-receptor tyrosine kinase Fyn plays a central role in oligodendrocyte differentiation and myelination. In order to improve our understanding of the role of oligodendroglial Fyn kinase, we have identified Fyn targets in these cells. Purification and mass-spectrometric analysis of tyrosine-phosphorylated proteins in response to overexpressed active Fyn in the oligodendrocyte precursor cell line Oli-neu, yielded the adaptor molecule p130Cas. We analyzed the function of this Fyn target in oligodendroglial cells and observed that reduction of p130Cas levels by siRNA affects process outgrowth, the thickness of cellular processes and migration behavior of Oli-neu cells. Furthermore, long term p130Cas reduction results in decreased cell numbers as a result of increased apoptosis in cultured primary oligodendrocytes. Our data contribute to understanding the molecular events taking place during oligodendrocyte migration and morphological differentiation and have implications for myelin formation.

  20. Perfluorooctane sulfonate induces neuronal and oligodendrocytic differentiation in neural stem cells and alters the expression of PPARγ in vitro and in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Wan Ibrahim, Wan Norhamidah, E-mail: hamidah@science.upm.edu.my [Department of Neuroscience, Karolinska Institutet, S-17177 Stockholm (Sweden); Tofighi, Roshan, E-mail: Roshan.Tofighi@ki.se [Department of Neuroscience, Karolinska Institutet, S-17177 Stockholm (Sweden); Onishchenko, Natalia, E-mail: Natalia.Onishchenko@ki.se [Department of Neuroscience, Karolinska Institutet, S-17177 Stockholm (Sweden); Rebellato, Paola, E-mail: Paola.Rebellato@ki.se [Department of Medical Biochemistry and Biophysics, Karolinska Institutet, S-17177 Stockholm (Sweden); Bose, Raj, E-mail: Raj.Bose@ki.se [Department of Neuroscience, Karolinska Institutet, S-17177 Stockholm (Sweden); Uhlén, Per, E-mail: Per.Uhlen@ki.se [Department of Medical Biochemistry and Biophysics, Karolinska Institutet, S-17177 Stockholm (Sweden); Ceccatelli, Sandra, E-mail: Sandra.Ceccatelli@ki.se [Department of Neuroscience, Karolinska Institutet, S-17177 Stockholm (Sweden)

    2013-05-15

    Perfluorinated compounds are ubiquitous chemicals of major concern for their potential adverse effects on the human population. We have used primary rat embryonic neural stem cells (NSCs) to study the effects of perfluorooctane sulfonate (PFOS) on the process of NSC spontaneous differentiation. Upon removal of basic fibroblast growth factor, NSCs were exposed to nanomolar concentrations of PFOS for 48 h, and then allowed to differentiate for additional 5 days. Exposure to 25 or 50 nM concentration resulted in a lower number of proliferating cells and a higher number of neurite-bearing TuJ1-positive cells, indicating an increase in neuronal differentiation. Exposure to 50 nM also significantly increased the number of CNPase-positive cells, pointing to facilitation of oligodendrocytic differentiation. PPAR genes have been shown to be involved in PFOS toxicity. By q-PCR we detected an upregulation of PPARγ with no changes in PPARα or PPARδ genes. One of the downstream targets of PPARs, the mitochondrial uncoupling protein 2 (UCP2) was also upregulated. The number of TuJ1- and CNPase-positive cells increased after exposure to PPARγ agonist rosiglitazone (RGZ, 3 μM) and decreased after pre-incubation with the PPARγ antagonist GW9662 (5 μM). RGZ also upregulated the expression of PPARγ and UCP2 genes. Meanwhile GW9662 abolished the UCP2 upregulation and decreased Ca{sup 2+} activity induced by PFOS. Interestingly, a significantly higher expression of PPARγ and UCP3 genes was also detected in mouse neonatal brain after prenatal exposure to PFOS. These data suggest that PPARγ plays a role in the alteration of spontaneous differentiation of NSCs induced by nanomolar concentrations of PFOS. - Highlights: • PFOS decreases proliferation of neural stem cells (NSCs). • PFOS induces neuronal and oligodendrocytic differentiation in NSCs. • PFOS alters expression of PPARγ and UCP2 in vitro. • PFOS alters expression of PPARγ and UCP3 in vivo. • Block of PPAR

  1. Cytoskeletal Linker Protein Dystonin Is Not Critical to Terminal Oligodendrocyte Differentiation or CNS Myelination.

    Directory of Open Access Journals (Sweden)

    Samantha F Kornfeld

    Full Text Available Oligodendrocyte differentiation and central nervous system myelination require massive reorganization of the oligodendrocyte cytoskeleton. Loss of specific actin- and tubulin-organizing factors can lead to impaired morphological and/or molecular differentiation of oligodendrocytes, resulting in a subsequent loss of myelination. Dystonin is a cytoskeletal linker protein with both actin- and tubulin-binding domains. Loss of function of this protein results in a sensory neuropathy called Hereditary Sensory Autonomic Neuropathy VI in humans and dystonia musculorum in mice. This disease presents with severe ataxia, dystonic muscle and is ultimately fatal early in life. While loss of the neuronal isoforms of dystonin primarily leads to sensory neuron degeneration, it has also been shown that peripheral myelination is compromised due to intrinsic Schwann cell differentiation abnormalities. The role of this cytoskeletal linker in oligodendrocytes, however, remains unclear. We sought to determine the effects of the loss of neuronal dystonin on oligodendrocyte differentiation and central myelination. To address this, primary oligodendrocytes were isolated from a severe model of dystonia musculorum, Dstdt-27J, and assessed for morphological and molecular differentiation capacity. No defects could be discerned in the differentiation of Dstdt-27J oligodendrocytes relative to oligodendrocytes from wild-type littermates. Survival was also compared between Dstdt-27J and wild-type oligodendrocytes, revealing no significant difference. Using a recently developed migration assay, we further analysed the ability of primary oligodendrocyte progenitor cell motility, and found that Dstdt-27J oligodendrocyte progenitor cells were able to migrate normally. Finally, in vivo analysis of oligodendrocyte myelination was done in phenotype-stage optic nerve, cerebral cortex and spinal cord. The density of myelinated axons and g-ratios of Dstdt-27J optic nerves was normal, as

  2. Whole-cell fungal transformation of precursors into dyes

    Directory of Open Access Journals (Sweden)

    Jarosz-Wilkołazka Anna

    2010-07-01

    Full Text Available Abstract Background Chemical methods of producing dyes involve extreme temperatures and unsafe toxic compounds. Application of oxidizing enzymes obtained from fungal species, for example laccase, is an alternative to chemical synthesis of dyes. Laccase can be replaced by fungal biomass acting as a whole-cell biocatalyst with properties comparable to the isolated form of the enzyme. The application of the whole-cell system simplifies the transformation process and reduces the time required for its completion. In the present work, four fungal strains with a well-known ability to produce laccase were tested for oxidation of 17 phenolic and non-phenolic precursors into stable and non-toxic dyes. Results An agar-plate screening test of the organic precursors was carried out using four fungal strains: Trametes versicolor, Fomes fomentarius, Abortiporus biennis, and Cerrena unicolor. Out of 17 precursors, nine were transformed into coloured substances in the presence of actively growing fungal mycelium. The immobilized fungal biomass catalyzed the transformation of 1 mM benzene and naphthalene derivatives in liquid cultures yielding stable and non-toxic products with good dyeing properties. The type of fungal strain had a large influence on the absorbance of the coloured products obtained after 48-hour transformation of the selected precursors, and the most effective was Fomes fomentarius (FF25. Whole-cell transformation of AHBS (3-amino-4-hydroxybenzenesulfonic acid into a phenoxazinone dye was carried out in four different systems: in aqueous media comprising low amounts of carbon and nitrogen source, in buffer, and in distilled water. Conclusions This study demonstrated the ability of four fungal strains belonging to the ecological type of white rot fungi to transform precursors into dyes. This paper highlights the potential of fungal biomass for replacing isolated enzymes as a cheaper industrial-grade biocatalyst for the synthesis of dyes and other

  3. Hemopoietic cell precursor responses to erythropoietin in plasma clot cultures

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, W.L.

    1979-01-01

    The time dependence of the response of mouse bone marrow cells to erythropoietin (Ep) in vitro was studied. Experiments include studies on the Ep response of marrow cells from normal, plethoric, or bled mice. Results with normal marrow reveal: (1) Not all erythroid precursors (CFU-E) are alike in their response to Ep. A significant number of the precursors develop to a mature erythroid colony after very short Ep exposures, but they account for only approx. 13% of the total colonies generated when Ep is active for 48 hrs. If Ep is active more than 6 hrs, a second population of erythroid colonies emerges at a nearly constant rate until the end of the culture. Full erythroid colony production requires prolonged exposure to erythropoietin. (2) The longer erythropoietin is actively present, the larger the number of erythroid colonies that reach 17 cells or more. Two distinct populations of immediate erythroid precursors are also present in marrow from plethoric mice. In these mice, total colony numbers are equal to or below those obtained from normal mice. However, the population of fast-responding CFU-E is consistently decreased to 10 to 20% of that found in normal marrow. The remaining colonies are formed from plethoric marrow at a rate equal to normal marrow. With increasing Ep exposures, the number of large colonies produced increases. From the marrow of bled mice, total erythroid colony production is equal to or above that of normal marrow. Two populations of colony-forming cells are again evident, with the fast-responding CFU-E being below normal levels. The lack of colonies from this group was compensated in bled mice by rapid colony production in the second population. A real increase in numbers of precursors present in this pool increased the rate of colony production in culture to twice that of normal marrow. The number of large colonies obtained from bled mice was again increased as the Ep exposure was lengthened. (ERB)

  4. Hyperforin promotes mitochondrial function and development of oligodendrocytes.

    Science.gov (United States)

    Wang, Yanlin; Zhang, Yanbo; He, Jue; Zhang, Handi; Xiao, Lan; Nazarali, Adil; Zhang, Zhijun; Zhang, Dai; Tan, Qingrong; Kong, Jiming; Li, Xin-Min

    2011-11-01

    St. John's wort has been found to be an effective and safe herbal treatment for depression in several clinical trials. However, the underlying mechanism of its therapeutic effects is unclear. Recent studies show that the loss and malfunction of oligodendrocytes are closely related to the neuropathological changes in depression, which can be reversed by antidepressant treatment. In this study, we evaluated the effects of hyperforin, a major active component of St. John's wort, on the proliferation, development and mitochondrial function of oligodendrocytes. The study results revealed that hyperforin promotes maturation of oligodendrocytes and increases mitochondrial function without affecting proliferation of an oligodendrocyte progenitor cell line and neural stem/progenitor cells. Hyperforin also prevented mitochondrial toxin-induced cytotoxicity in an oligodendrocyte progenitor cell line. These findings suggest that hyperforin may stimulate the development and function of oligodendrocytes, which could be a mechanism of its effect in depression. Future in vitro and in vivo studies are required to further characterize the mechanisms of hyperforin.

  5. Prolactin stimulates precursor cells in the adult mouse hippocampus.

    Directory of Open Access Journals (Sweden)

    Tara L Walker

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

  6. Suiciding of lymphocytic precursor cells by tritiated nucleosides, in vitro.

    Science.gov (United States)

    Uyeki, E M; Nishimura, T; Bisel, T U

    1978-02-01

    Differences in suiciding by various tritiated nucleosides were observed between two functional assays for in vitro lymphocytic precursor cell development, the hemolysin plaque-forming cell (PFC) assay and the B lymphocytic colony-forming cell (CFC-L) assay, using BDF1 mouse spleen cells. PFC growth was markedly reduced by an early (days 0-1) pulse of tritiated deoxyadenosine ([3H]dAdo), but relatively unaffected by a pulse of tritiated thymidine ([3H]dThd) during the same interval. In contrast, CFC-L formation significantly dropped after an early (day 0) [3H]dThd pulse, as well as after pulses of [3H]dAdo and the corresponding tritiated ribosides, uridine and adenosine. This implied a cycling state in an early lymphocytic precursor cell, as opposed to the PFC insensitivity to an early [3H]dThd pulse. The response pattern of colonies and clusters to [3H]dThd supported our notion of a delayed suiciding of CFC contributing to the increase in cluster numbers.

  7. 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.

  8. Human Oligodendrocytes in Remyelination Research

    NARCIS (Netherlands)

    Czepiel, Marcin; Boddeke, Erik; Copray, Sjef

    2015-01-01

    Studies on myelination and oligodendrocyte development are inevitably linked with demyelinating conditions such as multiple sclerosis (MS), leukodystrophies or spinal cord injury (SCI). Chronic loss of myelin, subsequently leading to neurodegeneration, is the ultimate cause of severe and permanent d

  9. Glutamate receptor-mediated toxicity in optic nerve oligodendrocytes

    Science.gov (United States)

    Matute, Carlos; Sánchez-Gómez, M. Victoria; Martínez-Millán, Luis; Miledi, Ricardo

    1997-01-01

    In cultured oligodendrocytes isolated from perinatal rat optic nerves, we have analyzed the expression of ionotropic glutamate receptor subunits as well as the effect of the activation of these receptors on oligodendrocyte viability. Reverse transcription–PCR, in combination with immunocytochemistry, demonstrated that most oligodendrocytes differentiated in vitro express the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunits GluR3 and GluR4 and the kainate receptor subunits GluR6, GluR7, KA1 and KA2. Acute and chronic exposure to kainate caused extensive oligodendrocyte death in culture. This effect was partially prevented by the AMPA receptor antagonist GYKI 52466 and was completely abolished by the non-N-methyl-d-aspartate receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), suggesting that both AMPA and kainate receptors mediate the observed kainate toxicity. Furthermore, chronic application of kainate to optic nerves in vivo resulted in massive oligodendrocyte death which, as in vitro, could be prevented by coinfusion of the toxin with CNQX. These findings suggest that excessive activation of the ionotropic glutamate receptors expressed by oligodendrocytes may act as a negative regulator of the size of this cell population. PMID:9238063

  10. 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.

  11. Notch signaling acts before cell division to promote asymmetric cleavage and cell fate of neural precursor cells.

    Science.gov (United States)

    Bhat, Krishna Moorthi

    2014-10-21

    Asymmetric cell divisions in the central nervous system generate neurons of diverse fates. In Drosophila melanogaster, the protein Numb localizes asymmetrically to dividing neural precursor cells such that only one daughter cell inherits Numb. Numb inhibits Notch signaling in this daughter cell, resulting in a different cell fate from the Notch-induced fate in the other-Numb-negative-daughter cell. Precursor cells undergo asymmetric cytokinesis generating daughter cells of different sizes. I found that inactivation of Notch in fly embryonic neural precursor cells disrupted the asymmetric positioning of the cleavage furrow and produced daughter cells of the same size and fate. Moreover, inactivation of Notch at different times altered the degree of asymmetric Numb localization, such that earlier inactivation of Notch caused symmetric distribution of Numb and later inactivation produced incomplete asymmetric localization of Numb. The extent of asymmetrically localized Numb positively correlated with the degree of asymmetric cytokinesis and the size disparity in daughter cells. Loss of Numb or expression of constitutively active Notch led to premature specification of the precursor cells into the fate of one of the daughter cells. Thus, in addition to its role in the specification of daughter cell fate after division, Notch controls Numb localization in the precursor cells to determine the size and fate of daughter cells. Numb also inhibits Notch signaling in precursor cells to prevent Notch-induced differentiation of the precursor cell, forming an autoregulatory loop. Copyright © 2014, American Association for the Advancement of Science.

  12. Regulation of the timing of oligodendrocyte differentiation:mechanisms and perspectives

    Institute of Scientific and Technical Information of China (English)

    Hao Huang; Xiao-Feng Zhao; Kang Zheng; Mengsheng Qiu

    2013-01-01

    Axonal myelination is an essential process for normal functioning of the vertebrate central nervous system.Proper formation of myelin sheaths around axons depends on the timely differentiation of oligodendrocytes.This differentiation occurs on a predictable schedule both in culture and during development.However,the timing mechanisms for oligodendrocyte differentiation during normal development have not been fully uncovered.Recent studies have identified a large number of regulatory factors,including cell-intrinsic factors and extracellular signals,that could control the timing of oligodendrocyte differentiation.Here we provide a mechanistic and critical review of the timing control of oligodendrocyte differentiation.

  13. Regulation of DM-20 mRNA expression and intracellular translocation of glutathione-S-transferase pi isoform during oligodendrocyte differentiation in the adult rat spinal cord.

    Science.gov (United States)

    Kitada, Masaaki; Takeda, Kazuya; Dezawa, Mari

    2016-07-01

    We previously demonstrated that NG2-positive oligodendrocyte precursor cells (OPCs) do not express DM-20 mRNA and identified a distinct DM-20 mRNA-positive cell population expressing glutathione-S-transferase pi isoform (GST-pi) in the nucleus (GST-pi(Nuc)) of the adult rat spinal cord. As GST-pi intranuclear localization correlates with progenitor cell properties, we examined the differentiation status of this cell population under the intensive 5-bromo-2'-deoxyuridine (BrdU) administration method, consisting of intraperitoneal BrdU injections every 2 h for 48 h. We observed that a certain population of proliferating/proliferated cells expressed DM-20 mRNA, and sometimes two proliferating/proliferated cells were observed still attached to each other. We performed triple staining for BrdU, DM-20 mRNA, and NG2 and found pairs of neighboring BrdU-positive cells, which were considered to originate from the same progenitor cells and where both cells expressed DM-20 mRNA. Triple staining for BrdU, DM-20 mRNA, and GST-pi detected proliferating/proliferated cells exhibiting the GST-pi(Nuc)/DM-20 mRNA-positive expression pattern. These findings suggested the presence of a GST-pi(Nuc)/DM-20 mRNA-positive oligodendrocyte-lineage progenitor cell population in the adult rat spinal cord. However, we did not find any pair of neighboring BrdU-positive cells with this expression pattern. These observations collectively support the idea that GST-pi(Nuc)/DM-20 mRNA-expressing cells are the progeny of NG2-positive OPCs rather than a novel type of oligodendrocyte-lineage progenitor cells and that DM-20 mRNA expression is dynamically regulated during differentiation of OPCs into oligodendrocytes.

  14. Functional integration of human neural precursor cells in mouse cortex.

    Directory of Open Access Journals (Sweden)

    Fu-Wen Zhou

    Full Text Available This study investigates the electrophysiological properties and functional integration of different phenotypes of transplanted human neural precursor cells (hNPCs in immunodeficient NSG mice. Postnatal day 2 mice received unilateral injections of 100,000 GFP+ hNPCs into the right parietal cortex. Eight weeks after transplantation, 1.21% of transplanted hNPCs survived. In these hNPCs, parvalbumin (PV-, calretinin (CR-, somatostatin (SS-positive inhibitory interneurons and excitatory pyramidal neurons were confirmed electrophysiologically and histologically. All GFP+ hNPCs were immunoreactive with anti-human specific nuclear protein. The proportions of PV-, CR-, and SS-positive cells among GFP+ cells were 35.5%, 15.7%, and 17.1%, respectively; around 15% of GFP+ cells were identified as pyramidal neurons. Those electrophysiologically and histological identified GFP+ hNPCs were shown to fire action potentials with the appropriate firing patterns for different classes of neurons and to display spontaneous excitatory and inhibitory postsynaptic currents (sEPSCs and sIPSCs. The amplitude, frequency and kinetic properties of sEPSCs and sIPSCs in different types of hNPCs were comparable to host cells of the same type. In conclusion, GFP+ hNPCs produce neurons that are competent to integrate functionally into host neocortical neuronal networks. This provides promising data on the potential for hNPCs to serve as therapeutic agents in neurological diseases with abnormal neuronal circuitry such as epilepsy.

  15. Laminin regulates postnatal oligodendrocyte production by promoting oligodendrocyte progenitor survival in the subventricular zone.

    Science.gov (United States)

    Relucio, Jenne; Menezes, Michael J; Miyagoe-Suzuki, Yuko; Takeda, Shin'ichi; Colognato, Holly

    2012-10-01

    The laminin family of extracellular matrix proteins are expressed broadly during embryonic brain development, but are enriched at ventricular and pial surfaces where laminins mediate radial glial attachment during corticogenesis. In the adult brain, however, laminin distribution is restricted, yet is found within the vascular basal lamina and associated fractones of the ventricular zone (VZ)-subventricular zone (SVZ) stem cell niche, where laminins regulate adult neural progenitor cell proliferation. It remains unknown, however, if laminins regulate the wave of oligodendrogenesis that occurs in the neonatal/early postnatal VZ-SVZ. Here we report that Lama2, the gene that encodes the laminin α2-subunit, regulates postnatal oligodendrogenesis. At birth, Lama2-/- mice had significantly higher levels of dying oligodendrocyte progenitor cells (OPCs) in the OPC germinal zone of the dorsal SVZ. This translated into fewer OPCs, both in the dorsal SVZ well as in an adjacent developing white matter tract, the corpus callosum. In addition, intermediate progenitor cells that give rise to OPCs in the Lama2-/- VZ-SVZ were mislocalized and proliferated nearer to the ventricle surface. Later, delays in oligodendrocyte maturation (with accompanying OPC accumulation), were observed in the Lama2-/- corpus callosum, leading to dysmyelination by postnatal day 21. Together these data suggest that prosurvival laminin interactions in the developing postnatal VZ-SVZ germinal zone regulate the ability, or timing, of oligodendrocyte production to occur appropriately.

  16. Oligodendrocytes and the control of myelination in vivo: new insights from the rat anterior medullary velum.

    Science.gov (United States)

    Butt, A M; Berry, M

    2000-02-15

    The rat anterior medullary velum (AMV) is representative of the brain and spinal cord, overall, and provides an almost two-dimensional preparation for investigating axon-glial interactions in vivo. Here, we review some of our findings on axon-oligodendrocyte unit relations in our adult, development, and injury paradigms: (1) adult oligodendrocytes are phenotypically heterogeneous, conforming to Del Rio Hortega's types I-IV, whereby differences in oligodendrocyte morphology, metabolism, myelin sheath radial and longitudinal dimensions, and biochemistry correlate with the diameters of axons in the unit; (2) oligodendrocytes derive from a common premyelinating oligodendrocyte phenotype, and divergence of types I-IV is related to the age they emerge and the presumptive diameter of axons in the unit; (3) during myelination, axon-oligodendrocyte units progress through a sequence of maturation phases, related to axon contact, ensheathment, establishment of internodal myelin sheaths, and finally the radial growth and compaction of the myelin sheath; (4) we provide direct in vivo evidence that platelet-derived growth factor-AA (PDGF-AA), fibroblast growth factor (FGF-2), and insulin-like growth factor-I (IGF-I) differentially regulate these events, by injecting the growth factors into the cerebrospinal fluid of neonatal rat pups; (5) in lesioned adult AMV, transected central nervous system (CNS) axons regenerate through the putatively inhibitory environment of the glial scar, but remyelination by oligodendrocytes is incomplete, indicating that axon-oligodendrocyte interactions are defective; and (6) in the adult AMV, cells expressing the NG2 chondroitin sulphate have a presumptive adult oligodendrocyte progenitor antigenic phenotype, but are highly complex cells and send processes to contact axolemma at nodes of Ranvier, suggesting they subserve a specific perinodal function. Thus, axons and oligodendrocyte lineage cells form interdependent functional units, but

  17. Precursors of executive function in infants with sickle cell anemia.

    Science.gov (United States)

    Hogan, Alexandra M; Telfer, Paul T; Kirkham, Fenella J; de Haan, Michelle

    2013-10-01

    Executive dysfunction occurs in sickle cell anemia, but there are few early data. Infants with sickle cell anemia (n = 14) and controls (n = 14) performed the "A-not-B" and Object Retrieval search tasks, measuring precursors of executive function at 9 and 12 months. Significant group differences were not found. However, for the A-not-B task, 7 of 11 sickle cell anemia infants scored in the lower 2 performance categories at 9 months, but only 1 at 12 months (P = .024); controls obtained scores at 12 months that were statistically comparable to the scores they had already obtained at 9 months. On the Object Retrieval task, 9- and 12-month controls showed comparable scores, whereas infants with sickle cell anemia continued to improve (P = .027); at 9 months, those with lower hemoglobin oxygen saturation passed fewer trials (R s = 0.670, P = .024) and took longer to obtain the toy (R s = -0.664, P = .013). Subtle delays in acquiring developmental skills may underlie abnormal executive function in childhood.

  18. On the biogenesis of the myelin sheath : Cognate polarized trafficking pathways in oligodendrocytes

    NARCIS (Netherlands)

    de Vries, H; Hoekstra, D

    2000-01-01

    Oligodendrocytes, the myelinating cells of the central nervous system, are capable of transporting vast quantities of proteins and of lipids, In particular galactosphingolipids, to the myelin sheath. The sheath is continuous with the plasma membrane of the oligodendrocyte, but the composition of bot

  19. Myocilin is involved in NgR1/Lingo-1-mediated oligodendrocyte differentiation and myelination of the optic nerve.

    Science.gov (United States)

    Kwon, Heung Sun; Nakaya, Naoki; Abu-Asab, Mones; Kim, Hong Sug; Tomarev, Stanislav I

    2014-04-16

    Myocilin is a secreted glycoprotein that belongs to a family of olfactomedin domain-containing proteins. Although myocilin is detected in several ocular and nonocular tissues, the only reported human pathology related to mutations in the MYOCILIN gene is primary open-angle glaucoma. Functions of myocilin are poorly understood. Here we demonstrate that myocilin is a mediator of oligodendrocyte differentiation and is involved in the myelination of the optic nerve in mice. Myocilin is expressed and secreted by optic nerve astrocytes. Differentiation of optic nerve oligodendrocytes is delayed in Myocilin-null mice. Optic nerves of Myocilin-null mice contain reduced levels of several myelin-associated proteins including myelin basic protein, myelin proteolipid protein, and 2'3'-cyclic nucleotide 3'-phosphodiesterase compared with those of wild-type littermates. This leads to reduced myelin sheath thickness of optic nerve axons in Myocilin-null mice compared with wild-type littermates, and this difference is more pronounced at early postnatal stages compared with adult mice. Myocilin also affects differentiation of oligodendrocyte precursors in vitro. Its addition to primary cultures of differentiating oligodendrocyte precursors increases levels of tested markers of oligodendrocyte differentiation and stimulates elongation of oligodendrocyte processes. Myocilin stimulation of oligodendrocyte differentiation occurs through the NgR1/Lingo-1 receptor complex. Myocilin physically interacts with Lingo-1 and may be considered as a Lingo-1 ligand. Myocilin-induced elongation of oligodendrocyte processes may be mediated by activation of FYN and suppression of RhoA GTPase.

  20. IL-1β induces hypomyelination in the periventricular white matter through inhibition of oligodendrocyte progenitor cell maturation via FYN/MEK/ERK signaling pathway in septic neonatal rats.

    Science.gov (United States)

    Xie, Di; Shen, Fengcai; He, Shaoru; Chen, Mengmeng; Han, Qianpeng; Fang, Ming; Zeng, Hongke; Chen, Chunbo; Deng, Yiyu

    2016-04-01

    Neuroinflammation elicited by microglia plays a key role in periventricular white matter (PWM) damage (PWMD) induced by infectious exposure. This study aimed to determine if microglia-derived interleukin-1β (IL-1β) would induce hypomyelination through suppression of maturation of oligodendrocyte progenitor cells (OPCs) in the developing PWM. Sprague-Dawley rats (1-day old) were injected with lipopolysaccharide (LPS) (1 mg/kg) intraperitoneally, following which upregulated expression of IL-1β and IL-1 receptor 1 (IL-1R1 ) was observed. This was coupled with enhanced apoptosis and suppressed proliferation of OPCs in the PWM. The number of PDGFR-α and NG2-positive OPCs was significantly decreased in the PWM at 24 h and 3 days after injection of LPS, whereas it was increased at 14 days and 28 days. The protein expression of Olig1, Olig2, and Nkx2.2 was significantly reduced, and mRNA expression of Tcf4 and Axin2 was upregulated in the developing PWM after LPS injection. The expression of myelin basic protein (MBP) and 2',3'-cyclic-nucleotide 3"-phosphodiesterase (CNPase) was downregulated in the PWM at 14 days and 28 days after LPS injection; this was linked to reduction of the proportion of myelinated axons and thinner myelin sheath as revealed by electron microscopy. Primary cultured OPCs treated with IL-1β showed the failure of maturation and proliferation. Furthermore, FYN/MEK/ERK signaling pathway was involved in suppression of maturation of primary OPCs induced by IL-1β administration. Our results suggest that following LPS injection, microglia are activated and produce IL-1β in the PWM in the neonatal rats. Excess IL-1β inhibits the maturation of OPCs via suppression of FYN/MEK/ERK phosphorylation thereby leading to axonal hypomyelination.

  1. Vaginal epithelial dendritic cells renew from bone marrow precursors.

    Science.gov (United States)

    Iijima, Norifumi; Linehan, Melissa M; Saeland, Sem; Iwasaki, Akiko

    2007-11-27

    Dendritic cells (DCs) represent key professional antigen-presenting cells capable of initiating primary immune responses. A specialized subset of DCs, the Langerhans cells (LCs), are located in the stratified squamous epithelial layer of the skin and within the mucosal epithelial lining of the vaginal and oral cavities. The vaginal mucosa undergoes cyclic changes under the control of sex hormones, and the renewal characteristics of the vaginal epithelial DCs (VEDCs) remain unknown. Here, we examined the origin of VEDCs. In contrast to the skin epidermal LCs, the DCs in the epithelium of the vagina were found to be repopulated mainly by nonmonocyte bone-marrow-derived precursors, with a half-life of 13 days under steady-state conditions. Upon infection with HSV-2, the Gr-1(hi) monocytes were found to give rise to VEDCs. Furthermore, flow cytometric analysis of the VEDCs revealed the presence of at least three distinct populations, namely, CD11b(+)F4/80(hi), CD11b(+)F4/80(int), and CD11b(-)F4/80(-). Importantly, these VEDC populations expressed CD207 at low levels and had a constitutively more activated phenotype compared with the skin LCs. Collectively, our results revealed mucosa-specific features of the VEDCs with respect to their phenotype, activation status, and homeostatic renewal potential.

  2. Polarity development in oligodendrocytes : Sorting and trafficking of myelin components

    NARCIS (Netherlands)

    Maier, Olaf; Hoekstra, Dick; Baron, Wia

    2008-01-01

    In vertebrates, myelination is required for the saltatory signal conductance along the axon. At the onset of myelination, the myelinating cells, i.e., oligodendrocytes in the central nervous system and Schwann cells in the peripheral nervous system, are heavily engaged in the biogenesis of membranes

  3. Lysophosphatidic Acid Receptor Is a Functional Marker of Adult Hippocampal Precursor Cells

    Directory of Open Access Journals (Sweden)

    Tara L. Walker

    2016-04-01

    Full Text Available Here, we show that the lysophosphatidic acid receptor 1 (LPA1 is expressed by a defined population of type 1 stem cells and type 2a precursor cells in the adult mouse dentate gyrus. LPA1, in contrast to Nestin, also marks the quiescent stem cell population. Combining LPA1-GFP with EGFR and prominin-1 expression, we have enabled the prospective separation of both proliferative and non-proliferative precursor cell populations. Transcriptional profiling of the isolated proliferative precursor cells suggested immune mechanisms and cytokine signaling as molecular regulators of adult hippocampal precursor cell proliferation. In addition to LPA1 being a marker of this important stem cell population, we also show that the corresponding ligand LPA is directly involved in the regulation of adult hippocampal precursor cell proliferation and neurogenesis, an effect that can be attributed to LPA signaling via the AKT and MAPK pathways.

  4. The relationship between developing oligodendrocyte units and maturing axons during myelinogenesis in the anterior medullary velum of neonatal rats.

    Science.gov (United States)

    Butt, A M; Ibrahim, M; Berry, M

    1997-05-01

    Myelinogenesis was investigated in whole-mounted anterior medullary vela from rats aged postnatal day (P) 10-12, using double immunofluorescence labelling with Rip and anti-neurofilament 200 (NF200) antibodies, to identify oligodendrocytes and axons, respectively. A number of discrete phases of maturation of oligodendrocyte units were recognised. (1) Promyelinating oligodendrocytes co-expressed Rip and Myelin basic Protein and formed axonal associations, prior to ensheathment. (2) Transitional oligodendrocytes contained both ensheathing and non-ensheating processes. (3) Myelinating oligodendrocytes were established after a period of remodelling (in which non-ensheathing processes were lost), appearing as oligodendrocyte unit morphological phenotypes with a definitive number of incipient myelin sheaths. (4) Maturation of myelinating oligodendrocytes was defined as the establishment of internodal sheath lengths and the redistrubution of myelin basic protein from the cell somata and radial processes into the myelin sheaths only. Myelination was probably related to the maturational state of the axons, since it was initiated when the latter had attained a critical diameter of between approximately 0.2 and 0.4 micron, coincident with the expression of NF200. Oligodendrocyte differentiation and myelination of the AMV were asynchronous and multifocal, and at P10: (1) axons which were destined to be of the largest calibre in the adult AMV were already myelinated by early developing oligodendrocytes, whilst those which were destined to be the smallest calibre in the adult were unmyelinated, but ultimately became ensheathed by late developing oligoendrocytes; (2) axons were sequentially ensheathed by early developing myelinating oligodendrocytes and late developing promyelinating oligodendrocytes; (3) all axons were small calibre; (4) oligodendrocyte units exhibited polymorphism. Thus, the development of oligodendrocyte morphological phenotypes was not related solely to

  5. Mechanisms regulating the development of oligodendrocytes and central nervous system myelin.

    Science.gov (United States)

    Mitew, S; Hay, C M; Peckham, H; Xiao, J; Koenning, M; Emery, B

    2014-09-12

    Oligodendrocytes and the myelin they produce are a remarkable vertebrate specialization that enables rapid and efficient nerve conduction within the central nervous system. The generation of myelin during development involves a finely-tuned pathway of oligodendrocyte precursor specification, proliferation and migration followed by differentiation and the subsequent myelination of appropriate axons. In this review we summarize the molecular mechanisms known to regulate each of these processes, including the extracellular ligands that promote or inhibit development of the oligodendrocyte lineage, the intracellular pathways they signal through and the key transcription factors that mediate their effects. Many of these regulatory mechanisms have recurring roles in regulating several transitions during oligodendrocyte development, highlighting their importance. It is also highly likely that many of these developmental mechanisms will also be involved in myelin repair in human neurological disease.

  6. Oligodendrocyte ablation as a tool to study demyelinating diseases

    Institute of Scientific and Technical Information of China (English)

    Ahdeah Pajoohesh-Ganji; Robert H. Miller

    2016-01-01

    Multiple sclerosis (MS) is an autoimmune mediated neurodegenerative disease characterized by demyelin-ation and oligodendrocyte (OL) loss in the central nervous system and accompanied by local inlfammation and inifltration of peripheral immune cells. Although many risk factors and symptoms have been iden-tified in MS, the pathology is complicated and the cause remains unknown. It is also unclear whether OL apoptosis precedes the inlfammation or whether the local inlfammation is the cause of OL death and demyelination. This review brielfy discusses several models that have been developed to speciifcally ablate oligodendrocytes in an effort to separate the effects of demyelination from inlfammation.

  7. Bone marrow B cell precursor number after allogeneic stem cell transplantation and GVHD development.

    Science.gov (United States)

    Fedoriw, Yuri; Samulski, T Danielle; Deal, Allison M; Dunphy, Cherie H; Sharf, Andrew; Shea, Thomas C; Serody, Jonathan S; Sarantopoulos, Stefanie

    2012-06-01

    Patients without chronic graft-versus-host disease (cGVHD) have robust B cell reconstitution and are able to maintain B cell homeostasis after allogeneic hematopoietic stem cell transplantation (HSCT). To determine whether B lymphopoiesis differs before cGVHD develops, we examined bone marrow (BM) biopsies for terminal deoxynucleotidyl transferase (TdT) and PAX5 immunostaining early post-HSCT at day 30 when all patients have been shown to have high B cell activating factor (BAFF) levels. We found significantly greater numbers of BM B cell precursors in patients who did not develop cGVHD compared with those who developed cGVHD (median = 44 vs 2 cells/high powered field [hpf]; respectively; P < .001). Importantly, a significant increase in precursor B cells was maintained when patients receiving high-dose steroid therapy were excluded (median = 49 vs 20 cells/hpf; P = .017). Thus, we demonstrate the association of BM B cell production capacity in human GVHD development. Increased BM precursor B cell number may serve to predict good clinical outcome after HSCT. Copyright © 2012 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  8. P2X7 receptors mediate ischemic damage to oligodendrocytes.

    Science.gov (United States)

    Domercq, Maria; Perez-Samartin, Alberto; Aparicio, David; Alberdi, Elena; Pampliega, Olatz; Matute, Carlos

    2010-04-15

    Brain ischemia leading to stroke is a major cause of disability in developed countries. Therapeutic strategies have most commonly focused on protecting neurons from ischemic damage. However, ischemic damage to white matter causes oligodendrocyte death, myelin disruption, and axon dysfunction, and it is partially mediated by glutamate excitotoxicity. We have previously demonstrated that oligodendrocytes express ionotropic purinergic receptors. The objective of this study was to investigate the role of purinergic signaling in white matter ischemia. We show that, in addition to glutamate, enhanced ATP signaling during ischemia is also deleterious to oligodendrocytes and myelin, and impairs white matter function. Thus, ischemic oligodendrocytes in culture display an inward current and cytosolic Ca(2+) overload, which is partially mediated by P2X7 receptors. Indeed, oligodendrocytes release ATP after oxygen and glucose deprivation through the opening of pannexin hemichannels. Consistently, ischemia-induced mitochondrial depolarization as well as oxidative stress culminating in cell death are partially reversed by P2X7 receptor antagonists, by the ATP degrading enzyme apyrase and by blockers of pannexin hemichannels. In turn, ischemic damage in isolated optic nerves, which share the properties of brain white matter, is greatly attenuated by all these drugs. Ultrastructural analysis and electrophysiological recordings demonstrated that P2X7 antagonists prevent ischemic damage to oligodendrocytes and myelin, and improved action potential recovery after ischemia. These data indicate that ATP released during ischemia and the subsequent activation of P2X7 receptor is critical to white matter demise during stroke and point to this receptor type as a therapeutic target to limit tissue damage in cerebrovascular diseases.

  9. Cell-type dependent modulation of Notch signaling by the amyloid precursor protein.

    Science.gov (United States)

    Oh, Sun Young; Chen, Ci-Di; Abraham, Carmela R

    2010-04-01

    The amyloid precursor protein is a ubiquitously expressed transmembrane protein that has been long implicated in the pathogenesis of Alzheimer's disease but its normal biological function has remained elusive despite extensive effort. We have previously reported the identification of Notch2 as an amyloid precursor protein interacting protein in E18 rat neurons. Here, we sought to reveal the physiologic consequences of this interaction. We report a functional relationship between amyloid precursor protein and Notch1, which does not affect Delta ligand binding. First, we observed interactions between the amyloid precursor protein and Notch in mouse embryonic stem cells lacking both presenilin 1 and presenilin 2, the active proteolytic components of the gamma-secretase complex, suggesting that these two transmembrane proteins can interact in the absence of presenilin. Next, we demonstrated that the amyloid precursor protein affects Notch signaling by using Notch-dependent luciferase assays in two cell lines, the human embryonic kidney 293 and the monkey kidney, COS7. We found that the amyloid precursor protein exerts opposing effects on Notch signaling in human embryonic kidney 293 vs. COS7 cells. Finally, we show that more Notch Intracellular Domain is found in the nucleus in the presence of exogenous amyloid precursor protein or its intracellular domain, suggesting the mechanism by which the amyloid precursor protein affects Notch signaling in certain cells. Our results provide evidence of potentially important communications between the amyloid precursor protein and Notch.

  10. A role for hemopexin in oligodendrocyte differentiation and myelin formation.

    Directory of Open Access Journals (Sweden)

    Noemi Morello

    Full Text Available Myelin formation and maintenance are crucial for the proper function of the CNS and are orchestrated by a plethora of factors including growth factors, extracellular matrix components, metalloproteases and protease inhibitors. Hemopexin (Hx is a plasma protein with high heme binding affinity, which is also locally produced in the CNS by ependymal cells, neurons and glial cells. We have recently reported that oligodendrocytes (OLs are the type of cells in the brain that are most susceptible to lack of Hx, as the number of iron-overloaded OLs increases in Hx-null brain, leading to oxidative tissue damage. In the current study, we found that the expression of the Myelin Basic Protein along with the density of myelinated fibers in the basal ganglia and in the motor and somatosensory cortex of Hx-null mice were strongly reduced starting at 2 months and progressively decreased with age. Myelin abnormalities were confirmed by electron microscopy and, at the functional level, resulted in the inability of Hx-null mice to perform efficiently on the Rotarod. It is likely that the poor myelination in the brain of Hx-null mice was a consequence of defective maturation of OLs as we demonstrated that the number of mature OLs was significantly reduced in mutant mice whereas that of precursor cells was normal. Finally, in vitro experiments showed that Hx promotes OL differentiation. Thus, Hx may be considered a novel OL differentiation factor and the modulation of its expression in CNS may be an important factor in the pathogenesis of human neurodegenerative disorders.

  11. Opioid precursor protein isoform is targeted to the cell nuclei in the human brain

    NARCIS (Netherlands)

    Kononenko, Olga; Bazov, Igor; Watanabe, Hiroyuki; Gerashchenko, Ganna; Dyachok, Oleg; Verbeek, Dineke S; Alkass, Kanar; Druid, Henrik; Andersson, Malin; Mulder, Jan; Svenningsen, Åsa Fex; Rajkowska, Grazyna; Stockmeier, Craig A; Krishtal, Oleg; Yakovleva, Tatiana; Bakalkin, Georgy

    2017-01-01

    BACKGROUND: Neuropeptide precursors are traditionally viewed as proteins giving rise to small neuropeptide molecules. Prodynorphin (PDYN) is the precursor protein to dynorphins, endogenous ligands for the κ-opioid receptor. Alternative mRNA splicing of neuropeptide genes may regulate cell- and tissu

  12. Perspectives on the role of Pannexin 1 in neural precursor cell biology

    Institute of Scientific and Technical Information of China (English)

    Juan C Sanchez-Arias; Leigh E Wicki-Stordeur; Leigh Anne Swayne

    2016-01-01

    We recently reported that targeted deletion of Pannexin 1 in neural precursor cells of the ventricular zone impairs the maintenance of these cells in healthy and stroke-injured brain. Here we frame this exciting new ifnding in the context of our previous studies on Pannexin 1 in neural precursors as well as the close rela-tionship between Pannexin 1 and purinergic receptors established by other groups. Moreover, we identify important gaps in our understanding of Pannexin 1 in neural precursor cell biology in terms of the under-lying molecular mechanisms and functional/behavioural outcomes.

  13. GH mediates exercise-dependent activation of SVZ neural precursor cells in aged mice.

    Directory of Open Access Journals (Sweden)

    Daniel G Blackmore

    Full Text Available Here we demonstrate, both in vivo and in vitro, that growth hormone (GH mediates precursor cell activation in the subventricular zone (SVZ of the aged (12-month-old brain following exercise, and that GH signaling stimulates precursor activation to a similar extent to exercise. Our results reveal that both addition of GH in culture and direct intracerebroventricular infusion of GH stimulate neural precursor cells in the aged brain. In contrast, no increase in neurosphere numbers was observed in GH receptor null animals following exercise. Continuous infusion of a GH antagonist into the lateral ventricle of wild-type animals completely abolished the exercise-induced increase in neural precursor cell number. Given that the aged brain does not recover well after injury, we investigated the direct effect of exercise and GH on neural precursor cell activation following irradiation. This revealed that physical exercise as well as infusion of GH promoted repopulation of neural precursor cells in irradiated aged animals. Conversely, infusion of a GH antagonist during exercise prevented recovery of precursor cells in the SVZ following irradiation.

  14. Synaptic network activity induces neuronal differentiation of adult hippocampal precursor cells through BDNF signaling

    Directory of Open Access Journals (Sweden)

    Harish Babu

    2009-09-01

    Full Text Available Adult hippocampal neurogenesis is regulated by activity. But how do neural precursor cells in the hippocampus respond to surrounding network activity and translate increased neural activity into a developmental program? Here we show that long-term potential (LTP-like synaptic activity within a cellular network of mature hippocampal neurons promotes neuronal differentiation of newly generated cells. In co-cultures of precursor cells with primary hippocampal neurons, LTP-like synaptic plasticity induced by addition of glycine in Mg2+-free media for 5 min, produced synchronous network activity and subsequently increased synaptic strength between neurons. Furthermore, this synchronous network activity led to a significant increase in neuronal differentiation from the co-cultured neural precursor cells. When applied directly to precursor cells, glycine and Mg2+-free solution did not induce neuronal differentiation. Synaptic plasticity-induced neuronal differentiation of precursor cells was observed in the presence of GABAergic neurotransmission blockers but was dependent on NMDA-mediated Ca2+ influx. Most importantly, neuronal differentiation required the release of brain-derived neurotrophic factor (BDNF from the underlying substrate hippocampal neurons as well as TrkB receptor phosphorylation in precursor cells. This suggests that activity-dependent stem cell differentiation within the hippocampal network is mediated via synaptically evoked BDNF signaling.

  15. Cre-inducible site-specific recombination in zebrafish oligodendrocytes.

    Science.gov (United States)

    Pinzon-Olejua, Alejandro; Welte, Cornelia; Chekuru, Avinash; Bosak, Viktoria; Brand, Michael; Hans, Stefan; Stuermer, Claudia A O

    2017-01-01

    The conditional Cre/lox system has recently emerged as a valuable tool for studies on both embryonic and adult Zebrafish. Temporal control and site-specific recombination are achieved by using the ligand-inducible CreER(T2) and administration of the drug tamoxifen (TAM) or its active metabolite, 4-Hydroxytamoxifen (4-OHT). Here we report the generation of a transgenic Zebrafish line, which expresses an mCherry-tagged variant of CreER(T2) under the control of the myelin basic protein a (mbpa) promoter. Our analysis shows that larval and adult expression of the transgene recapitulates the endogenous mbpa expression pattern in oligodendrocytes. Furthermore, combination with a Cre-dependent EGFP reporter results in EGFP-expressing oligodendrocytes in the spinal cord, brain, and optic nerve in TAM- or 4-OHT-treated larvae and 4-month-old fish, but not in untreated controls. The transgenic Zebrafish line Tg(mbpa:mCherry-T2A-CreER(T2) ) elicits CreER(T2) expression specifically in myelinating glia cells. Cre-inducible targeted recombination of genes in oligodendrocytes will be useful to elucidate cellular and molecular mechanisms of myelination in vivo during development (myelination) and regeneration (remyelination) after injury to the central nervous system (CNS). It will also allow targeted expression and overexpression of genes of interest (transgenes) in oligodendrocytes at defined developmental and adult stages. Developmental Dynamics 246:41-49, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  16. Inducible T-cell receptor expression in precursor T-cells for leukemia control

    Science.gov (United States)

    Hoseini, Shahabuddin S; Hapke, Martin; Herbst, Jessica; Wedekind, Dirk; Baumann, Rolf; Heinz, Niels; Schiedlmeier, Bernhard; Vignali, Dario AA; van den Brink, Marcel R.M.; Schambach, Axel; Blazar, Bruce R.; Sauer, Martin G.

    2015-01-01

    Co-transplantation of hematopoietic stem cells with those engineered to express leukemia-reactive T cell receptors (TCRs) and differentiated ex vivo into precursor T cells (preTs) may reduce the risk of leukemia relapse. Since expression of potentially self-(leukemia-) reactive TCRs will lead to negative selection or provoke autoimmunity upon thymic maturation, we investigated a novel concept whereby TCR expression set under the control of an inducible promoter would allow timely controlled TCR expression. After in vivo maturation and gene induction, preTs developed potent anti-leukemia effects. Engineered preTs provided protection even after repeated leukemia challenges by giving rise to effector and central memory cells. Importantly, adoptive transfer of TCR-transduced allogeneic preTs mediated anti-leukemia effect without evoking graft-versus-host disease (GVHD). Earlier transgene induction forced CD8+ T cell development, was required to obtain a mature T cell subset of targeted specificity, allowed engineered T cells to efficiently pass positive selection and abrogated the endogenous T cell repertoire. Later induction favored CD4 differentiation and failed to produce a leukemia-reactive population emphasizing the dominant role of positive selection. Taken together, we provide new functional insights for the employment of TCR-engineered precursor cells as a controllable immunotherapeutic modality with significant anti-leukemia activity. PMID:25652739

  17. 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.

  18. Overexpression of CD44 in neural precursor cells improves trans-endothelial migration and facilitates their invasion of perivascular tissues in vivo.

    Directory of Open Access Journals (Sweden)

    Cyrille Deboux

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

  19. Evidence for local expansion of IgA plasma cell precursors in human ileum

    NARCIS (Netherlands)

    Yuvaraj, S.; Dijkstra, G.; Burgerhof, J.G.M.; Dammers, P.M.; Stoel, M.; Visser, Annie; Kroese, F.G.M.; Bos, N.A.

    2009-01-01

    IgA plays a crucial role in establishment and maintenance of mucosal homeostasis between host cells and commensal bacteria. To this end, numerous IgA plasma cells are located in the intestinal lamina propria. Whether the (immediate) precursor cells for these plasma cells can expand locally is not

  20. Effects of endotoxin on proliferation of human hematopoietic cell precursors

    OpenAIRE

    Rinehart, John J.; Keville, Lisa

    1997-01-01

    In examining the effects of corticosteroids on hematopoiesis in vitro, we observed that results were highly dependent on the lot of commercial fetal calf serum (FCS) utilized. We hypothesized that this variability correlated with the picogram (pg) level of endotoxin contaminating the FCS. Randomly obtained commercial lots of FCS contained 0.39 to 187 pg/ml of lipopolysaccharide (LPS). Standard FCS concentrations in hematopoietic precursor proliferation assays (granulocyte-marcrophage colony f...

  1. Insulin-like growth factor binding protein-1 activates integrin-mediated intracellular signaling and migration in oligodendrocytes

    NARCIS (Netherlands)

    Chesik, Daniel; De Keyser, Jacques; Bron, Reinier; Fuhler, Gwenny M.

    2010-01-01

    P>In multiple sclerosis (MS), oligodendrocytes in lesions are lost, leaving damaged tissue virtually devoid of these myelin-producing cells. Our group has recently demonstrated enhanced expression of insulin-like growth factor (IGF) binding protein-1 (IGFBP-1) in oligodendrocytes (CNPase+) localized

  2. Direct Genesis of Functional Rodent and Human Schwann Cells from Skin Mesenchymal Precursors

    Directory of Open Access Journals (Sweden)

    Matthew P. Krause

    2014-07-01

    Full Text Available Recent reports of directed reprogramming have raised questions about the stability of cell lineages. Here, we have addressed this issue, focusing upon skin-derived precursors (SKPs, a dermally derived precursor cell. We show by lineage tracing that murine SKPs from dorsal skin originate from mesenchymal and not neural crest-derived cells. These mesenchymally derived SKPs can, without genetic manipulation, generate functional Schwann cells, a neural crest cell type, and are highly similar at the transcriptional level to Schwann cells isolated from the peripheral nerve. This is not a mouse-specific phenomenon, since human SKPs that are highly similar at the transcriptome level can be made from neural crest-derived facial and mesodermally derived foreskin dermis and the foreskin SKPs can make myelinating Schwann cells. Thus, nonneural crest-derived mesenchymal precursors can differentiate into bona fide peripheral glia in the absence of genetic manipulation, suggesting that developmentally defined lineage boundaries are more flexible than widely thought.

  3. Derivation of Neural Precursor Cells from Human Embryonic Stem Cells for DNA Methylomic Analysis.

    Science.gov (United States)

    Roubal, Ivan; Park, Sun Joo; Kim, Yong

    2016-01-01

    Embryonic stem cells are self-renewing pluripotent cells with competency to differentiate into all three-germ lineages. Many studies have demonstrated the importance of genetic and epigenetic molecular mechanisms in the maintenance of self-renewal and pluripotency. Stem cells are under unique molecular and cellular regulations different from somatic cells. Proper regulation should be ensured to maintain their unique self-renewal and undifferentiated characteristics. Understanding key mechanisms in stem cell biology will be important for the successful application of stem cells for regenerative therapeutic medicine. More importantly practical use of stem cells will require our knowledge on how to properly direct and differentiate stem cells into the necessary type of cells. Embryonic stem cells and adult stem cells have been used as study models to unveil molecular and cellular mechanisms in various signaling pathways. They are especially beneficial to developmental studies where in vivo molecular/cellular study models are not available. We have derived neural stem cells from human embryonic stem cells as a model to study the effect of teratogen in neural development. We have tested commercial neural differentiation system and successfully derived neural precursor cells exhibiting key molecular features of neural stem cells, which will be useful for experimental application.

  4. Induction of Skin-Derived Precursor Cells from Human Induced Pluripotent Stem Cells

    Science.gov (United States)

    Sugiyama-Nakagiri, Yoriko; Fujimura, Tsutomu; Moriwaki, Shigeru

    2016-01-01

    The generation of full thickness human skin from dissociated cells is an attractive approach not only for treating skin diseases, but also for treating many systemic disorders. However, it is currently not possible to obtain an unlimited number of skin dermal cells. The goal of this study was to develop a procedure to produce skin dermal stem cells from induced pluripotent stem cells (iPSCs). Skin-derived precursor cells (SKPs) were isolated as adult dermal precursors that could differentiate into both neural and mesodermal progenies and could reconstitute the dermis. Thus, we attempted to generate SKPs from iPSCs that could reconstitute the skin dermis. Human iPSCs were initially cultured with recombinant noggin and SB431542, an inhibitor of activin/nodal and TGFβ signaling, to induce neural crest progenitor cells. Those cells were then treated with SKP medium that included CHIR99021, a WNT signal activator. The induction efficacy from neural crest progenitor cells to SKPs was more than 97%. No other modifiers tested were able to induce those cells. Those human iPSC-derived SKPs (hiPSC-SKPs) showed a similar gene expression signature to SKPs isolated from human skin dermis. Human iPSC-SKPs differentiated into neural and mesodermal progenies, including adipocytes, skeletogenic cell types and Schwann cells. Moreover, they could be induced to follicular type keratinization when co-cultured with human epidermal keratinocytes. We here provide a new efficient protocol to create human skin dermal stem cells from hiPSCs that could contribute to the treatment of various skin disorders. PMID:27992514

  5. Oligodendrocyte and interneuron density in hippocampal subfields in schizophrenia and association of oligodendrocyte number with cognitive deficits

    Directory of Open Access Journals (Sweden)

    Peter eFalkai

    2016-03-01

    differences in Olig1-, Olig2-, or parvalbumin-positive cell density between schizophrenia patients and controls in any of the subregions of the posterior hippocampus.Based on the results from our stereological study we hypothesize that a decreased number of oligodendrocytes in the anterior and entire hippocampus may be involved in cognitive deficits by impairing the connectivity of this structure in schizophrenia. In the posterior hippocampus, we could not replicate previously reported findings of decreased interneurons from the entire hippocampus.

  6. Vitreous humor and albumin augment the proliferation of cultured retinal precursor cells

    DEFF Research Database (Denmark)

    Yang, Jing; Klassen, Henry; Pries, Mette

    2008-01-01

    Intravitreal injection is an important delivery route for studies involving the transplantation of various types of precursor cells to the retina; however, the effect on these cells of exposure to the vitreous microenvironment has not been specifically investigated. Here vitreous humor was evalua......Intravitreal injection is an important delivery route for studies involving the transplantation of various types of precursor cells to the retina; however, the effect on these cells of exposure to the vitreous microenvironment has not been specifically investigated. Here vitreous humor...... was evaluated for the potential to influence the proliferation of rat retinal precursor cells in vitro. Cells were isolated at embryonic day 19 and plated in standard proliferation medium in the presence or absence of fluid expressed from porcine vitreous humor. Cellular proliferation at different...

  7. Bone marrow precursors: a model explaining radio-protection by opposite cell cycle-acting cytokines

    Energy Technology Data Exchange (ETDEWEB)

    Dalmau, Sergio Ranto; Coelho, Marsen G.P. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Dept. de Bioquimica; Freitas, Claudia Sondermann [Instituto nacional do Cancer, Rio de Janeiro, RJ (Brazil). Centro de Pesquisa Basica

    1997-12-31

    Full text. Cytokines such as interleukin-1 (IL-1), tumor necrosis factor alpha (TNF-a), stem cell factor (SCF), and interleukin-12 (IL-12) are presently known to exert a radioprotective effect on bone marrow (BM) precursor cells. IL-1, SCF, and IL-12 are known to promote BM precursor cell cycling. Conversely, TNF-a and TGF-b, the latter a radio sensitizer, induce cycle arrest in these cells. Cycling is known to increase radioprotection. Therefore, the mechanism by which TNF-a exerts radio-protection on BM precursors is unclear. However, IL-1 and TNF-a are unique among these cytokines in their ability to induce detoxifying mechanisms. Supported on the literature, the present communication proposes a model, based on the induction of biochemical detoxifying mechanisms, aiming to explain BM cell radio-protection by opposite cell cycle-acting cytokines

  8. Contribution of constitutively proliferating precursor cell subtypes to dentate neurogenesis after cortical infarcts

    Directory of Open Access Journals (Sweden)

    Oberland Julia

    2010-11-01

    Full Text Available Abstract Background It is well known that focal ischemia increases neurogenesis in the adult dentate gyrus of the hippocampal formation but the cellular mechanisms underlying this proliferative response are only poorly understood. We here investigated whether precursor cells which constitutively proliferate before the ischemic infarct contribute to post-ischemic neurogenesis. To this purpose, transgenic mice expressing green fluorescent protein (GFP under the control of the nestin promoter received repetitive injections of the proliferation marker bromodeoxyuridine (BrdU prior to induction of cortical infarcts. We then immunocytochemically analyzed the fate of these BrdU-positive precursor cell subtypes from day 4 to day 28 after the lesion. Results Quantification of BrdU-expressing precursor cell populations revealed no alteration in number of radial glia-like type 1 cells but a sequential increase of later precursor cell subtypes in lesioned animals (type 2a cells at day 7, type 3 cells/immature neurons at day 14. These alterations result in an enhanced survival of mature neurons 4 weeks postinfarct. Conclusions Focal cortical infarcts recruit dentate precursor cells generated already before the infarct and significantly contribute to an enhanced neurogenesis. Our findings thereby increase our understanding of the complex cellular mechanisms of postlesional neurogenesis.

  9. Impaired precursor B cell differentiation in Bruton's tyrosine kinase-deficient mice

    NARCIS (Netherlands)

    S. Middendorp; G.M. Dingjan (Gemma); R.W. Hendriks (Rudi)

    2002-01-01

    textabstractBruton's tyrosine kinase (Btk) is a cytoplasmic signaling molecule that is crucial for precursor (pre-B) cell differentiation in humans. In this study, we show that during the transition of large cycling to small resting pre-B cells in the mouse, Btk-deficient cells fai

  10. Impaired precursor B cell differentiation in Bruton's tyrosine kinase-deficient mice

    NARCIS (Netherlands)

    S. Middendorp; G.M. Dingjan (Gemma); R.W. Hendriks (Rudi)

    2002-01-01

    textabstractBruton's tyrosine kinase (Btk) is a cytoplasmic signaling molecule that is crucial for precursor (pre-B) cell differentiation in humans. In this study, we show that during the transition of large cycling to small resting pre-B cells in the mouse, Btk-deficient cells

  11. Plectasin, a Fungal Defensin, Targets the Bacterial Cell Wall Precursor Lipid II

    DEFF Research Database (Denmark)

    Schneider, Tanja; Kruse, Thomas; Wimmer, Reinhard

    2010-01-01

    that plectasin, a fungal defensin, acts by directly binding the bacterial cell-wall precursor Lipid II. A wide range of genetic and biochemical approaches identify cell-wall biosynthesis as the pathway targeted by plectasin. In vitro assays for cell-wall synthesis identified Lipid II as the specific cellular...

  12. Regulation of Asymmetric Cell Division in Mammalian Neural Stem and Cancer Precursor Cells.

    Science.gov (United States)

    Daynac, Mathieu; Petritsch, Claudia K

    Stem and progenitor cells are characterized by their abilities to self-renew and produce differentiated progeny. The balance between self-renewal and differentiation is achieved through control of cell division mode, which can be either asymmetric or symmetric. Failure to properly control cell division mode may result in premature depletion of the stem/progenitor cell pool or abnormal growth and impaired differentiation. In many tissues, including the brain, stem cells and progenitor cells undergo asymmetric cell division through the establishment of cell polarity. Cell polarity proteins are therefore potentially critical regulators of asymmetric cell division. Decrease or loss of asymmetric cell division can be associated with reduced differentiation common during aging or impaired remyelination as seen in demyelinating diseases. Progenitor-like glioma precursor cells show decreased asymmetric cell division rates and increased symmetric divisions, which suggests that asymmetric cell division suppresses brain tumor formation. Cancer stem cells, on the other hand, still undergo low rates of asymmetric cell division, which may provide them with a survival advantage during therapy. These findings led to the hypotheses that asymmetric cell divisions are not always tumor suppressive but can also be utilized to maintain a cancer stem cell population. Proper control of cell division mode is therefore not only deemed necessary to generate cellular diversity during development and to maintain adult tissue homeostasis but may also prevent disease and determine disease progression. Since brain cancer is most common in the adult and aging population, we review here the current knowledge on molecular mechanisms that regulate asymmetric cell divisions in the neural and oligodendroglial lineage during development and in the adult brain.

  13. A protocol for isolation and enriched monolayer cultivation of neural precursor cells from mouse dentate gyrus

    Directory of Open Access Journals (Sweden)

    Harish eBabu

    2011-07-01

    Full Text Available In vitro assays are valuable tools to study the characteristics of adult neural precursor cells under controlled conditions with a defined set of parameters. We here present a detailed protocol based on our previous original publication (Babu et al., Enriched monolayer precursor cell cultures from micro-dissected adult mouse dentate gyrus yield functional granule cell-like neurons, PLoS One 2007, 2:e388 to isolate neural precursor cells from the hippocampus of adult mice and maintain and propagate them as adherent monolayer cultures. The strategy is based on the use of Percoll density gradient centrifugation to enrich precursor cells from the micro-dissected dentate gyrus. Based on the expression of Nestin and Sox2, a culture-purity of more than 98% can be achieved. The cultures are expanded under serum-free conditions in Neurobasal A medium with addition of the mitogens EGF and FGF2 as well as the supplements Glutamax-1 and B27. Under differentiation conditions, the precursor cells reliably generate approximately 30% neurons with appropriate morphological, molecular and electrophysiological characteristics that might reflect granule cell properties as their in vivo counterpart. We also highlight potential modifications to the protocol.

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

    Directory of Open Access Journals (Sweden)

    Hui-Fang Chang

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

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

    Science.gov (United States)

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

    2016-01-01

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

  16. Cerebellar granule cells are predominantly generated by terminal symmetric divisions of granule cell precursors.

    Science.gov (United States)

    Nakashima, Kie; Umeshima, Hiroki; Kengaku, Mineko

    2015-06-01

    Neurons in the central nervous system (CNS) are generated by symmetric and asymmetric cell division of neural stem cells and their derivative progenitor cells. Cerebellar granule cells are the most abundant neurons in the CNS, and are generated by intensive cell division of granule cell precursors (GCPs) during postnatal development. Dysregulation of GCP cell cycle is causal for some subtypes of medulloblastoma. However, the details and mechanisms underlying neurogenesis from GCPs are not well understood. Using long-term live-cell imaging of proliferating GCPs transfected with a fluorescent newborn-granule cell marker, we found that GCPs underwent predominantly symmetric divisions, generating two GCPs or two neurons, while asymmetric divisions generating a GCP and a neuron were only occasionally observed, in both dissociated culture and within tissues of isolated cerebellar lobules. We found no significant difference in cell cycle length between proliferative and neurogenic divisions, or any consistent changes in cell cycle length during repeated proliferative division. Unlike neural stem cells in the cerebral cortex and spinal cord, which generate many neurons by repeated asymmetric division, cerebellar GCPs produce neurons predominantly by terminal symmetric division. These results indicate diverse mechanisms of neurogenesis in the mammalian brain. © 2015 Wiley Periodicals, Inc.

  17. On the biogenesis of the myelin sheath: cognate polarized trafficking pathways in oligodendrocytes.

    Science.gov (United States)

    de Vries, H; Hoekstra, D

    2000-01-01

    Oligodendrocytes, the myelinating cells of the central nervous system, are capable of transporting vast quantities of proteins and of lipids, in particular galactosphingolipids, to the myelin sheath. The sheath is continuous with the plasma membrane of the oligodendrocyte, but the composition of both membrane domains differs substantially. Given its high glycosphingolipid and cholesterol content the myelin sheath bears similarity to the lipid composition of the apical domain of a polarized cell. The question thus arises whether myelin components, like typical apical membrane proteins are transported by an apical-like trafficking mechanism to the sheath, involving a 'raft'-mediated mechanism. Indeed, the evidence indicates the presence of cognate apical and basolateral pathways in oligodendrocytes. However, all major myelin proteins do not participate in this pathway, and remarkably apical-like trafficking seems to be restricted to the oligodendrocyte cell body. In this review, we summarize the evidence on the existence of different trafficking pathways in the oligodendrocyte, and discuss possible mechanisms separating the oligodendrocyte's membrane domains.

  18. In vitro generation of motor neuron precursors from mouse embryonic stem cells using mesoporous nanoparticles

    DEFF Research Database (Denmark)

    Garcia-Bennett, Alfonso E; König, Niclas; Abrahamsson, Ninnie

    2014-01-01

    Aim: Stem cell-derived motor neurons (MNs) are utilized to develop replacement strategies for spinal cord disorders. Differentiation of embryonic stem cells into MN precursors involves factors and their repeated administration. We investigated if delivery of factors loaded into mesoporous...

  19. Generation of GABAergic and dopaminergic interneurons from endogenous embryonic olfactory bulb precursor cells.

    Science.gov (United States)

    Vergaño-Vera, Eva; Yusta-Boyo, María J; de Castro, Fernando; Bernad, Antonio; de Pablo, Flora; Vicario-Abejón, Carlos

    2006-11-01

    During the embryonic period, many olfactory bulb (OB) interneurons arise in the lateral ganglionic eminence (LGE) from precursor cells expressing Dlx2, Gsh2 and Er81 transcription factors. Whether GABAergic and dopaminergic interneurons are also generated within the embryonic OB has not been studied thoroughly. In contrast to abundant Dlx2 and Gsh2 expression in ganglionic eminences (GE), Dlx2 and Gsh2 proteins are not expressed in the E12.5-13.5 mouse OB, whereas the telencephalic pallial domain marker Pax6 is abundant. We found GABAergic and dopaminergic neurons originating from dividing precursor cells in E13.5 OB and in short-term dissociated cultures prepared from the rostral half of E13.5 OB. In OB cultures, 22% of neurons were GAD+, of which 53% were Dlx2+, whereas none expressed Gsh2. By contrast, 70% of GAD+ cells in GE cultures were Dlx2+ and 16% expressed Gsh2. In E13.5 OB slices transplanted with EGFP-labeled E13.5 OB precursor cells, 31.7% of EGFP+ cells differentiated to GABAergic neurons. OB and LGE precursors transplanted into early postnatal OB migrated and differentiated in distinct patterns. Transplanted OB precursors gave rise to interneurons with dendritic spines in close proximity to synaptophysin-positive boutons. Interneurons were also abundant in differentiating OB neural stem cell cultures; the neurons responded to the neurotrophin Bdnf and expressed presynaptic proteins. In vivo, the Bdnf receptor TrkB colocalized with synaptic proteins at the glomeruli. These findings suggest that, in addition to receiving interneurons from the LGE, the embryonic OB contains molecularly distinct local precursor cells that generate mature GABAergic and dopaminergic neurons.

  20. T cell precursor migration towards beta 2-microglobulin is involved in thymus colonization of chicken embryos

    DEFF Research Database (Denmark)

    Dunon, D; Kaufman, J; Salomonsen, J;

    1990-01-01

    beta 2-microglobulin (beta 2m) attracts hemopoietic precursors from chicken bone marrow cells in vitro. The cell population responding to beta 2m increases during the second period of thymus colonization, which takes place at days 12-14 of incubation. The precursors from 13.5 day old embryos were...... isolated after migration towards beta 2m in vitro and shown to be able to colonize a 13 day old thymus in ovo, where they subsequently acquire thymocyte markers. In contrast these beta 2m responsive precursors did not colonize embryonic bursa, i.e. differentiate into B lymphocytes. During chicken...... embryogenesis, peaks of beta 2m transcripts and of free beta 2m synthesis can only be detected in the thymus. The peak of free beta 2m synthesis in the thymus and the increase of beta 2m responding bone marrow cells both occur concomitantly with the second wave of thymus colonization in chicken embryo, facts...

  1. Acute hepatitis A induction of precursor B-cell acute lymphoblastic leukemia: a causal relationship?

    Science.gov (United States)

    Senadhi, V; Emuron, D; Gupta, R

    2010-09-01

    Precursor B-cell acute lymphoblastic leukemia accounts for 2% of all lymphoid neoplasms in the United States and occurs most frequently in childhood, but can also occur in adults with a median age of 39 years. It is more commonly seen in males and in Caucasians. We present a case of a 51-year-old Caucasian female with the development of precursor B-cell acute lymphoblastic leukemia after suffering acute hepatitis A 4 weeks prior to her diagnosis. She presented with malaise for a month without spontaneous bruising/bleeding, infections, or B-symptoms, such as fevers, night sweats, or unintentional weight loss. Nonspecific viral transformation of bone marrow has been discussed in the literature, but we specifically describe hepatitis A-induced adult-onset precursor B-cell acute lymphoblastic leukemia, which is the first reported case in the literature.

  2. Over-expression of hNGF in adult human olfactory bulb neural stem cells promotes cell growth and oligodendrocytic differentiation

    NARCIS (Netherlands)

    H.E.S. Marei (Hany); A. Althani (Asmaa); N. Afifi (Nahla); A. Abd-Elmaksoud (Ahmed); C. Bernardini (Camilla); F. Michetti (Fabrizio); M. Barba (Marta); M. Pescatori (Mario); G. Maira (Giulio); E. Paldino (Emanuela); L. Manni (Luigi); P. Casalbore (Patrizia); C. Cenciarelli (Carlo)

    2013-01-01

    textabstractThe adult human olfactory bulb neural stem/progenitor cells (OBNC/PC) are promising candidate for cell-based therapy for traumatic and neurodegenerative insults. Exogenous application of NGF was suggested as a promising therapeutic strategy for traumatic and neurodegenerative diseases, h

  3. Axon-myelin sheath relations of oligodendrocyte unit phenotypes in the adult rat anterior medullary velum.

    Science.gov (United States)

    Butt, A M; Ibrahim, M; Berry, M

    1998-04-01

    Axon-oligodendrocyte relations of Rip-immunolabelled and dye-injected oligodendrocyte units are characterised in the adult rat anterior medullary velum (AMV). Each oligodendrocyte unit comprised the oligodendrocyte cell body, processes and the internodal myelin segments they support. Oligodendrocyte units corresponded to classically described type I/II or type III/IV unit phenotypes which respectively myelinated discrete populations of small and large diameter axons, delineated by a myelinated fire diameter of 2-4 microns (diameter of the axon plus its myelin sheath). Within units, mean fibre diameter was directly related to mean internodal length and inversely related to the number of myelin sheaths in the unit. The relationship between fibre diameter and internodal length was retained in units which myelinated axons of different diameters, indicating that axon diameter was an important determinant of the longitudinal dimensions of myelin sheaths. We also show that type III/IV units maintained a far greater volume of myelin than type I/II units. It was concluded that type I/II and III/IV oligodendrocytes represent two functionally and morphologically distinct phenotypes whose distribution densities were determined by the diameter and spatial dispersion of axons.

  4. SNX27, a protein involved in down syndrome, regulates GPR17 trafficking and oligodendrocyte differentiation.

    Science.gov (United States)

    Meraviglia, Veronica; Ulivi, Alessandro Francesco; Boccazzi, Marta; Valenza, Fabiola; Fratangeli, Alessandra; Passafaro, Maria; Lecca, Davide; Stagni, Fiorenza; Giacomini, Andrea; Bartesaghi, Renata; Abbracchio, Maria P; Ceruti, Stefania; Rosa, Patrizia

    2016-08-01

    The G protein-coupled receptor 17 (GPR17) plays crucial roles in myelination. It is highly expressed during transition of oligodendrocyte progenitor cells to immature oligodendrocytes, but, after this stage, it must be down-regulated to allow generation of mature myelinating cells. After endocytosis, GPR17 is sorted into lysosomes for degradation or recycled to the plasma membrane. Balance between degradation and recycling is important for modulation of receptor levels at the cell surface and thus for the silencing/activation of GPR17-signaling pathways that, in turn, affect oligodendrocyte differentiation. The molecular mechanisms at the basis of these processes are still partially unknown and their characterization will allow a better understanding of myelination and provide cues to interpret the consequences of GPR17 dysfunction in diseases. Here, we demonstrate that the endocytic trafficking of GPR17 is mediated by the interaction of a type I PDZ-binding motif located at the C-terminus of the receptor and SNX27, a recently identified protein of the endosome-associated retromer complex and whose functions in oligodendrocytes have never been studied. SNX27 knock-down significantly reduces GPR17 plasma membrane recycling in differentiating oligodendrocytes while accelerating cells' terminal maturation. Interestingly, trisomy-linked down-regulation of SNX27 expression in the brain of Ts65Dn mice, a model of Down syndrome, correlates with a decrease in GPR17(+) cells and an increase in mature oligodendrocytes, which, however, fail in reaching full maturation, eventually leading to hypomyelination. Our data demonstrate that SNX27 modulates GPR17 plasma membrane recycling and stability, and that disruption of the SNX27/GPR17 interaction might contribute to pathological oligodendrocyte differentiation defects. GLIA 2016. GLIA 2016;64:1437-1460.

  5. Characterization of Porcine Ventral Mesencephalic Precursor Cells following Long-Term Propagation in 3D Culture

    Directory of Open Access Journals (Sweden)

    Pia S. Jensen

    2012-01-01

    Full Text Available The potential use of predifferentiated neural precursor cells for treatment of a neurological disorder like Parkinson’s disease combines stem cell research with previous experimental and clinical transplantation of developing dopaminergic neurons. One current obstacle is, however, the lack of ability to generate dopaminergic neurons after long-term in vitro propagation of the cells. The domestic pig is considered a useful nonprimate large animal model in neuroscience, because of a better resemblance of the larger gyrencephalic pig brain to the human brain than the commonly used brains of smaller rodents. In the present study, porcine embryonic (28–30 days, ventral mesencephalic precursor cells were isolated and propagated as free-floating neural tissue spheres in medium containing epidermal growth factor and fibroblast growth factor 2. For passaging, the tissue spheres were cut into quarters, avoiding mechanical or enzymatic dissociation in order to minimize cellular trauma and preserve intercellular contacts. Spheres were propagated for up to 237 days with analysis of cellular content and differentiation at various time points. Our study provides the first demonstration that porcine ventral mesencephalic precursor cells can be long-term propagated as neural tissue spheres, thereby providing an experimental 3D in vitro model for studies of neural precursor cells, their niche, and differentiation capacity.

  6. Epithelial cell identity in hyperplastic precursors of breast cancer

    Institute of Scientific and Technical Information of China (English)

    Danila Coradini; Patrizia Boracchi; Saro Oriana; Elia Biganzoli; Federico Ambrogi

    2015-01-01

    Introduction:In the adult human breast, hyperplastic enlarged lobular unit (HELU) and atypical ductal hyperplasia (ADH) are two common abnormalities that frequently coexist with ductal carcinoma in situ (DCIS). For this reason, they have been proposed as the early steps in a biological continuum toward breast cancer. Methods:We investigated in silico the expression of 369 genes experimentally recognized as involved in establishing and maintaining epithelial cell identity and mammary gland remodeling, in HELUs or ADHs with respect to the corresponding patient-matched normal tissue. Results:Despite the common luminal origin, HELUs and ADHs proved to be characterized by distinct gene profiles that overlap for 5 genes only. While HELUs were associated with the overexpression of progesterone receptor (PGR), ADHs were characterized by the overexpression of estrogen receptor 1 (ESR1) coupled with the overexpression of some proliferation-associated genes. Conclusions:This unexpected finding contradicts the notion that in differentiated luminal cells the expression of estrogen receptor (ER) is dissociated from cell proliferation and suggests that the establishing of an ER-dependent signaling is able to sustain cell proliferation in an autocrine manner as an early event in tumor initiation. Although clinical evidence indicates that only a fraction of HELUs and ADHs evolve to invasive cancer, present findings warn that exposure to synthetic progestins, frequently administered as hormone-replacement therapy, and estrogens, when abnormally produced by adipose cells and persistently present in the stroma surrounding the mammary gland, may cause these hyperplastic lesions.

  7. Isolation of Precursor Cells from Waste Solid Fat Tissue

    Science.gov (United States)

    Byerly, Diane; Sognier, Marguerite A.

    2009-01-01

    A process for isolating tissue-specific progenitor cells exploits solid fat tissue obtained as waste from such elective surgical procedures as abdominoplasties (tummy tucks) and breast reductions. Until now, a painful and risky process of aspiration of bone marrow has been used to obtain a limited number of tissue- specific progenitor cells. The present process yields more tissue-specific progenitor cells and involves much less pain and risk for the patient. This process includes separation of fat from skin, mincing of the fat into small pieces, and forcing a fat saline mixture through a sieve. The mixture is then digested with collagenase type I in an incubator. After centrifugation tissue-specific progenitor cells are recovered and placed in a tissue-culture medium in flasks or Petri dishes. The tissue-specific progenitor cells can be used for such purposes as (1) generating three-dimensional tissue equivalent models for studying bone loss and muscle atrophy (among other deficiencies) and, ultimately, (2) generating replacements for tissues lost by the fat donor because of injury or disease.

  8. N-acylethanolamines and precursor phospholipids - Relation to cell injury

    DEFF Research Database (Denmark)

    Hansen, Harald S.; Moesgaard, B.; Hansen, H.H.

    2000-01-01

    mitochondria, and direct inhibition of ceramidase. Anandamide (20:4-NAE) is formed as a minor component along with other NAEs during cell injury. Whether 20:4-NAE has a separate physiological role is at present not known, but some data suggest that 20:4-NAE may be formed, e.g. in the uterus, by a more......The present review focuses on the relationship between formation of N-acylethanolamine phospholipids (NAPEs) and N-acyletransferase (NAEs) catalyzed by N-acyltranferase and NAPE-hydrolyzing phospholipase D, respectively, and cell injury in tissues like brain, heart, and testis. A number...

  9. Myelin Oligodendrocyte Glycoprotein: Deciphering a Target in Inflammatory Demyelinating Diseases

    Directory of Open Access Journals (Sweden)

    Patrick Peschl

    2017-05-01

    Full Text Available Myelin oligodendrocyte glycoprotein (MOG, a member of the immunoglobulin (Ig superfamily, is a myelin protein solely expressed at the outermost surface of myelin sheaths and oligodendrocyte membranes. This makes MOG a potential target of cellular and humoral immune responses in inflammatory demyelinating diseases. Due to its late postnatal developmental expression, MOG is an important marker for oligodendrocyte maturation. Discovered about 30 years ago, it is one of the best-studied autoantigens for experimental autoimmune models for multiple sclerosis (MS. Human studies, however, have yielded controversial results on the role of MOG, especially MOG antibodies (Abs, as a biomarker in MS. But with improved detection methods using different expression systems to detect Abs in patients’ samples, this is meanwhile no longer the case. Using cell-based assays with recombinant full-length, conformationally intact MOG, several recent studies have revealed that MOG Abs can be found in a subset of predominantly pediatric patients with acute disseminated encephalomyelitis (ADEM, aquaporin-4 (AQP4 seronegative neuromyelitis optica spectrum disorders (NMOSD, monophasic or recurrent isolated optic neuritis (ON, or transverse myelitis, in atypical MS and in N-methyl-d-aspartate receptor-encephalitis with overlapping demyelinating syndromes. Whereas MOG Abs are only transiently observed in monophasic diseases such as ADEM and their decline is associated with a favorable outcome, they are persistent in multiphasic ADEM, NMOSD, recurrent ON, or myelitis. Due to distinct clinical features within these diseases it is controversially disputed to classify MOG Ab-positive cases as a new disease entity. Neuropathologically, the presence of MOG Abs is characterized by MS-typical demyelination and oligodendrocyte pathology associated with Abs and complement. However, it remains unclear whether MOG Abs are a mere inflammatory bystander effect or truly pathogenetic

  10. Fine-tuning oligodendrocyte development by miRNAs

    Directory of Open Access Journals (Sweden)

    Richard eLu

    2012-02-01

    Full Text Available Myelination of axons by oligodendrocytes in the central nervous system is essential for normal neuronal functions. The failure of remyelination due to injury or pathological insults results in devastating demyelinating diseases. Oligodendrocytes originate in restricted regions of the embryonic ventral neural tube. After migration to populate all areas of the brain and spinal cord, they undergo a temporally well-defined series of molecular and structural changes, ultimately culminating in the cessation of proliferation, and the elaboration of a highly complex myelin sheath. The emergence of microRNAs as potent regulators of gene expression at the post-transcriptional level has broad implications in all facets of biology. Recent studies have demonstrated a critical role of microRNAs in oligodendrocyte development, including cell proliferation, maturation, and myelin formation. In this review, we will highlight and discuss the recent understanding of functional links of miRNAs to regulatory networks for central myelination, as well as perspectives on the role of miRNAs in demyelinating diseases.

  11. PROGRAMMED CELL DEATH IN EXTRAOCULAR MUSCLE TENDON/SCLERA PRECURSORS

    Science.gov (United States)

    AbstractPurpose: This study was designed to examine the occurrence of natural cell death in the periocular mesenchyme of mouse embryos. Methods: Vital staining with LysoTracker Red and Nile blue sulphate as well as terminal nick end labeling (TUNEL) were utiliz...

  12. PROGRAMMED CELL DEATH IN EXTRAOCULAR MUSCLE TENDON/SCLERA PRECURSORS

    Science.gov (United States)

    AbstractPurpose: This study was designed to examine the occurrence of natural cell death in the periocular mesenchyme of mouse embryos. Methods: Vital staining with LysoTracker Red and Nile blue sulphate as well as terminal nick end labeling (TUNEL) were utiliz...

  13. Differentiation of Mouse Embryonic Stem Cells into Ventral Foregut Precursors

    DEFF Research Database (Denmark)

    Rothová, Michaela; Hölzenspies, Jurriaan J; Livigni, Alessandra

    2016-01-01

    endoderm with pronounced anterior character. ADE-containing cultures can be produced in vitro by suspension (embryoid body) culture or in a serum-free adherent monolayer culture. ESC-derived ADE cells are committed to endodermal fates and can undergo further differentiation in vitro towards ventral foregut...

  14. Transplanted neural stem/precursor cells instruct phagocytes and reduce secondary tissue damage in the injured spinal cord.

    Science.gov (United States)

    Cusimano, Melania; Biziato, Daniela; Brambilla, Elena; Donegà, Matteo; Alfaro-Cervello, Clara; Snider, Silvia; Salani, Giuliana; Pucci, Ferdinando; Comi, Giancarlo; Garcia-Verdugo, Jose Manuel; De Palma, Michele; Martino, Gianvito; Pluchino, Stefano

    2012-02-01

    Transplanted neural stem/precursor cells possess peculiar therapeutic plasticity and can simultaneously instruct several therapeutic mechanisms in addition to cell replacement. Here, we interrogated the therapeutic plasticity of neural stem/precursor cells after their focal implantation in the severely contused spinal cord. We injected syngeneic neural stem/precursor cells at the proximal and distal ends of the contused mouse spinal cord and analysed locomotor functions and relevant secondary pathological events in the mice, cell fate of transplanted neural stem/precursor cells, and gene expression and inflammatory cell infiltration at the injured site. We used two different doses of neural stem/precursor cells and two treatment schedules, either subacute (7 days) or early chronic (21 days) neural stem/precursor cell transplantation after the induction of experimental thoracic severe spinal cord injury. Only the subacute transplant of neural stem/precursor cells enhanced the recovery of locomotor functions of mice with spinal cord injury. Transplanted neural stem/precursor cells survived undifferentiated at the level of the peri-lesion environment and established contacts with endogenous phagocytes via cellular-junctional coupling. This was associated with significant modulation of the expression levels of important inflammatory cell transcripts in vivo. Transplanted neural stem/precursor cells skewed the inflammatory cell infiltrate at the injured site by reducing the proportion of 'classically-activated' (M1-like) macrophages, while promoting the healing of the injured cord. We here identify a precise window of opportunity for the treatment of complex spinal cord injuries with therapeutically plastic somatic stem cells, and suggest that neural stem/precursor cells have the ability to re-programme the local inflammatory cell microenvironment from a 'hostile' to an 'instructive' role, thus facilitating the healing or regeneration past the lesion.

  15. Blockade of microglial KATP -channel abrogates suppression of inflammatory-mediated inhibition of neural precursor cells.

    Science.gov (United States)

    Ortega, Francisco J; Vukovic, Jana; Rodríguez, Manuel J; Bartlett, Perry F

    2014-02-01

    Microglia positively affect neural progenitor cell physiology through the release of inflammatory mediators or trophic factors. We demonstrated previously that reactive microglia foster K(ATP) -channel expression and that blocking this channel using glibenclamide administration enhances striatal neurogenesis after stroke. In this study, we investigated whether the microglial K(ATP) -channel directly influences the activation of neural precursor cells (NPCs) from the subventricular zone using transgenic Csf1r-GFP mice. In vitro exposure of NPCs to lipopolysaccharide and interferon-gamma resulted in a significant decrease in precursor cell number. The complete removal of microglia from the culture or exposure to enriched microglia culture also decreased the precursor cell number. The addition of glibenclamide rescued the negative effects of enriched microglia on neurosphere formation and promoted a ∼20% improvement in precursor cell number. Similar results were found using microglial-conditioned media from isolated microglia. Using primary mixed glial and pure microglial cultures, glibenclamide specifically targeted reactive microglia to restore neurogenesis and increased the microglial production of the chemokine monocyte chemoattractant protein-1 (MCP-1). These findings provide the first direct evidence that the microglial K(ATP) -channel is a regulator of the proliferation of NPCs under inflammatory conditions.

  16. Non-Viral Generation of Neural Precursor-like Cells from Adult Human Fibroblasts

    Directory of Open Access Journals (Sweden)

    Maucksch C

    2012-01-01

    Full Text Available Recent studies have reported direct reprogramming of human fibroblasts to mature neurons by the introduction of defined neural genes. This technology has potential use in the areas of neurological disease modeling and drug development. However, use of induced neurons for large-scale drug screening and cell-based replacement strategies is limited due to their inability to expand once reprogrammed. We propose it would be more desirable to induce expandable neural precursor cells directly from human fibroblasts. To date several pluripotent and neural transcription factors have been shown to be capable of converting mouse fibroblasts to neural stem/precursor-like cells when delivered by viral vectors. Here we extend these findings and demonstrate that transient ectopic insertion of the transcription factors SOX2 and PAX6 to adult human fibroblasts through use of non-viral plasmid transfection or protein transduction allows the generation of induced neural precursor (iNP colonies expressing a range of neural stem and pro-neural genes. Upon differentiation, iNP cells give rise to neurons exhibiting typical neuronal morphologies and expressing multiple neuronal markers including tyrosine hydroxylase and GAD65/67. Importantly, iNP-derived neurons demonstrate electrophysiological properties of functionally mature neurons with the capacity to generate action potentials. In addition, iNP cells are capable of differentiating into glial fibrillary acidic protein (GFAP-expressing astrocytes. This study represents a novel virus-free approach for direct reprogramming of human fibroblasts to a neural precursor fate.

  17. Sonic hedgehog-expressing basal cells are general post-mitotic precursors of functional taste receptor cells

    Science.gov (United States)

    Miura, Hirohito; Scott, Jennifer K.; Harada, Shuitsu; Barlow, Linda A.

    2014-01-01

    Background Taste buds contain ~60 elongate cells and several basal cells. Elongate cells comprise three functional taste cell types: I - glial cells, II - bitter/sweet/umami receptor cells, and III - sour detectors. Although taste cells are continuously renewed, lineage relationships among cell types are ill-defined. Basal cells have been proposed as taste bud stem cells, a subset of which express Sonic hedgehog (Shh). However, Shh+ basal cells turnover rapidly suggesting that Shh+ cells are precursors of some or all taste cell types. Results To fate map Shh-expressing cells, mice carrying ShhCreERT2 and a high (CAG-CAT-EGFP) or low (R26RLacZ) efficiency reporter allele were given tamoxifen to activate Cre in Shh+ cells. Using R26RLacZ, lineage-labeled cells occur singly within buds, supporting a post-mitotic state for Shh+ cells. Using either reporter, we show that Shh+ cells differentiate into all three taste cell types, in proportions reflecting cell type ratios in taste buds (I > II > III). Conclusions Shh+ cells are not stem cells, but are post-mitotic, immediate precursors of taste cells. Shh+ cells differentiate into each of the three taste cell types, and the choice of a specific taste cell fate is regulated to maintain the proper ratio within buds. PMID:24590958

  18. Proteomic analysis of osteogenic differentiation of dental follicle precursor cells

    DEFF Research Database (Denmark)

    Morsczeck, Christian; Petersen, Jørgen; Völlner, Florian

    2009-01-01

    proteins, plastin 3 T-isoform, beta-actin, superoxide dismutases, and transgelin were found to be highly up-regulated, whereas cofilin-1, pro-alpha 1 collagen, destrin, prolyl 4-hydrolase and dihydrolipoamide dehydrogenase were found to be highly down-regulated. The group of up-regulated proteins...... is associated with actin-bundling and defence against oxidative cellular stress, whereas down-regulated proteins were associated with collagen biosynthesis. Bioinformatic analyses of the entire data set confirmed these findings that represent significant steps towards the understanding of DFPC differentiation....... The bioinformatic analyses suggest that proteins associated with cell cycle progression and protein metabolism were down-regulated and proteins involved in catabolism, cell motility and biological quality were up-regulated. These results display the general physiological state of DFPCs before and after osteogenic...

  19. IL-9-Producing Mast Cell Precursors and Food Allergy

    Science.gov (United States)

    2016-10-01

    Faculty of Allied Health Sciences, Thammasat University, Bangkok; cthe Department of Immunology, University of Texas and MD Anderson Cancer Center...www.healthline.com/ health -news/scientists-discover-new-cell- that-may-be-key-to-food-allergies-092215 (2) Peer-Reviewed Scientific Journals: (i) Chen...Peyer’s patch (PP), mesenteric lymph nodes (MLNs), spleen, lung, or liver (Figure 1I). Together, these results suggest an association of Lin IL-9

  20. Alcohol-Induced Molecular Dysregulation in Human Embryonic Stem Cell-Derived Neural Precursor Cells

    Science.gov (United States)

    Kim, Yi Young; Roubal, Ivan; Lee, Youn Soo; Kim, Jin Seok; Hoang, Michael; Mathiyakom, Nathan; Kim, Yong

    2016-01-01

    Adverse effect of alcohol on neural function has been well documented. Especially, the teratogenic effect of alcohol on neurodevelopment during embryogenesis has been demonstrated in various models, which could be a pathologic basis for fetal alcohol spectrum disorders (FASDs). While the developmental defects from alcohol abuse during gestation have been described, the specific mechanisms by which alcohol mediates these injuries have yet to be determined. Recent studies have shown that alcohol has significant effect on molecular and cellular regulatory mechanisms in embryonic stem cell (ESC) differentiation including genes involved in neural development. To test our hypothesis that alcohol induces molecular alterations during neural differentiation we have derived neural precursor cells from pluripotent human ESCs in the presence or absence of ethanol treatment. Genome-wide transcriptomic profiling identified molecular alterations induced by ethanol exposure during neural differentiation of hESCs into neural rosettes and neural precursor cell populations. The Database for Annotation, Visualization and Integrated Discovery (DAVID) functional analysis on significantly altered genes showed potential ethanol’s effect on JAK-STAT signaling pathway, neuroactive ligand-receptor interaction, Toll-like receptor (TLR) signaling pathway, cytokine-cytokine receptor interaction and regulation of autophagy. We have further quantitatively verified ethanol-induced alterations of selected candidate genes. Among verified genes we further examined the expression of P2RX3, which is associated with nociception, a peripheral pain response. We found ethanol significantly reduced the level of P2RX3 in undifferentiated hESCs, but induced the level of P2RX3 mRNA and protein in hESC-derived NPCs. Our result suggests ethanol-induced dysregulation of P2RX3 along with alterations in molecules involved in neural activity such as neuroactive ligand-receptor interaction may be a molecular event

  1. Specific labeling of peptidoglycan precursors as a tool for bacterial cell wall studies

    NARCIS (Netherlands)

    van Dam, V.|info:eu-repo/dai/nl/304833908; Olrichs, N.K.|info:eu-repo/dai/nl/304837571; Breukink, E.J.|info:eu-repo/dai/nl/120305100

    2009-01-01

    Wall chart: The predominant component of the bacterial cell wall, peptidoglycan, consists of long alternating stretches of aminosugar subunits interlinked in a large three-dimensional network and is formed from precursors through several cytosolic and membrane-bound steps. The high tolerance of the

  2. Smooth Muscle Precursor Cells Derived from Human Pluripotent Stem Cells for Treatment of Stress Urinary Incontinence

    Science.gov (United States)

    Wang, Zhe; Li, Yan Hui; Wei, Yi; Green, Morgaine; Wani, Prachi; Zhang, Pengbo; Pera, Renee Reijo; Chen, Bertha

    2016-01-01

    There is great interest in using stem cells (SC) to regenerate a deficient urethral sphincter in patients with urinary incontinence. The smooth muscle component of the sphincter is a significant contributor to sphincter function. However, current translational efforts for sphincter muscle restoration focus only on skeletal muscle regeneration because they rely on adult mesenchymal SC as cell source. These adult SC do not yield sufficient smooth muscle cells (SMCs) for transplantation. We may be able to overcome this limitation by using pluripotent stem cell (PSC) to derive SMCs. Hence, we sought to investigate whether smooth muscle precursor cells (pSMCs) derived from human PSCs can restore urethral function in an animal model generated by surgical urethrolysis and ovariectomy. Rats were divided into four groups: control (no intervention), sham saline (surgery + saline injection), bladder SMC (surgery + human bladder SMC injection), and treatment (surgery + pSMC injection, which includes human embryonic stem cell (hESC) H9-derived pSMC, episomal reprogrammed induced pluripotent stem cells (iPSCs)-derived pSMC, or viral reprogrammed iPSC-derived pSMC). pSMCs (2 × 106 cells/rat) were injected periurethrally 3 weeks postsurgery. Leak point pressure (LPP) and baseline external urethral sphincter electromyography were measured 5 weeks postinjection. Both iPSC-derived pSMC treatment groups showed significantly higher LPP compared to the sham saline group, consistent with restoration of urethral sphincter function. While the difference between the H9-derived pSMC treatment and sham saline group was not significant, it did show a trend toward restoration of the LPP to the level of intact controls. Our data indicate that pSMCs derived from human PSCs (hESC and iPSC) can restore sphincter function. PMID:26785911

  3. The Mesenchymal Precursor Cell Marker Antibody STRO-1 Binds to Cell Surface Heat Shock Cognate 70.

    Science.gov (United States)

    Fitter, Stephen; Gronthos, Stan; Ooi, Soo Siang; Zannettino, Andrew C W

    2016-12-27

    Since its discovery more than 25 years ago, the STRO-1 antibody has played a fundamental role in defining the hierarchical nature of mesenchymal precursor cells (MPC) and their progeny. STRO-1 antibody binding remains a hallmark of immature pluripotent MPC. Despite the significance of STRO-1 in the MPC field, the identity of the antigen has remained elusive. Using a combination of two-dimensional gel electrophoresis, coupled with Western blotting and Tandem mass spectroscopy, we have identified the STRO-1 antigen as heat shock cognate 70 (HSC70;HSPA8). STRO-1 binds to immune-precipitated HSC70 and siRNA-mediated knock down of HSPA8 reduced STRO-1 binding. STRO-1 surface binding does not correlate with HSC70 expression and sequestration of cholesterol reduces STRO-1 surface binding, suggesting that the plasma membrane lipid composition may be an important determinant in the presentation of HSC70 on the cell surface. HSC70 is present on the surface of STRO-1(+) but not STRO-1(-) cell lines as assessed by cell surface biotinylation and recombinant HSC70 blocks STRO-1 binding to the cell surface. The STRO-1 epitope on HSC70 was mapped to the ATPase domain using a series of deletion mutants in combination with peptide arrays. Deletion of the first four amino acids of the consensus epitope negated STRO-1 binding. Notably, in addition to HSC70, STRO-1 cross-reacts with heat shock protein 70 (HSP70), however all the clonogenic cell activity is restricted to the STRO-1(BRIGHT) /HSP70(-) fraction. These results provide important insight into the properties that define multipotent MPC and provide the impetus to explore the role of cell surface HSC70 in MPC biology. Stem Cells 2016.

  4. Primary orbital precursor T-cell lymphoblastic lymphoma

    DEFF Research Database (Denmark)

    Stenman, Lisa; Persson, Marta; Enlund, Fredrik

    2016-01-01

    Primary T-cell lymphoblastic lymphoma (T-LBL) in the eye region is very rare. The present study described a unique case of T-LBL involving the extraocular muscles. A 22-year-old male patient presented with a 3-week history of headache, reduced visual acuity and edema of the left eye. Clinical....... There was no involvement of the bone marrow. Based on the clinical and histopathological findings, a diagnosis of T-LBL was made. There was no evidence of NOTCH1 mutation or rearrangements of the ETV6 and MLL genes and high-resolution array-based comparative genomic hybridization (arrayCGH) analysis revealed a normal...... genomic profile. The patient received chemotherapy according to the high-risk NOPHO protocol, followed by myeloablative allogenic bone marrow transplantation. At 35 months after diagnosis, the patient remained in complete first remission, but without light perception on his left eye. To the best of our...

  5. Comparison of neurosphere-like cell clusters derived from dental follicle precursor cells and retinal Müller cells

    DEFF Research Database (Denmark)

    Beck, Hans Christian; Petersen, Jørgen; Felthaus, Oliver

    2011-01-01

    Unrelated cells such as dental follicle precursor cells (DFPCs) and retinal Müller cells (MCs) make spheres after cultivation in serum-replacement medium (SRM). Until today, the relation and molecular processes of sphere formation from different cell types remain undescribed. Thus in this study we...... compared proteomes of spheres derived from MCs and DFPCs. 73% of 676 identified proteins were similar expressed in both cell types and many of them are expressed in the brain (55%). Moreover proteins are overrepresented that are associated with pathways for neural diseases such as Huntington disease...... or Alzheimer disease. Interestingly up-regulated proteins in DFPCs are involved in the biosynthesis of glycosphingolipids. These lipids are components of gangliosides such as GD3, which is a novel neural stem cell marker. In conclusion spheres from different types of cells have highly similar proteomes...

  6. MENINGES HARBOR CELLS EXPRESSING NEURAL PRECURSOR MARKERS DURING DEVELOPMENT AND ADULTHOOD

    Directory of Open Access Journals (Sweden)

    Francesco eBifari

    2015-10-01

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

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

    Science.gov (United States)

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

    2015-01-01

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

  8. Deficient leukemia inhibitory factor signaling in muscle precursor cells from patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Broholm, Christa; Brandt, Claus; Schultz, Ninna S

    2012-01-01

    The cytokine leukemia-inhibitory factor (LIF) is expressed by skeletal muscle and induces proliferation of muscle precursor cells, an important feature of skeletal muscle maintenance and repair. We hypothesized that muscle precursor cells from patients with type 2 diabetes had a deficient response......-stimulated cell proliferation and a decreased LIF-stimulated induction of the proliferation-promoting factors cyclin D1, JunB, and c-myc. SOCS3 protein was upregulated in diabetic myoblasts, and knockdown of SOCS3 rescued LIF-induced gene expression in diabetic myoblasts, whereas neither STAT1 or STAT3 signaling...... nor proliferation rate was affected. In conclusion, although LIF and LIFR proteins were increased in muscle tissue and myoblasts from diabetic patients, LIF signaling and LIF-stimulated cell proliferation were impaired in diabetic myoblasts, suggesting a novel mechanism by which muscle function...

  9. Culture of rat cerebral oligodendrocytes in a serum-free, chemically defined medium

    NARCIS (Netherlands)

    Koper, J.W.; Lopes-Cardozo, M.; Romijn, H.J.; Golde, L.M.G. van

    1984-01-01

    Oligodendrocytes were isolated from the cerebra of young rats (5-10 days old) by trypsinization of the tissue followed by cell separation on Percoll gradients. The isolation was carried out in physiological, isotonic media. The cell yield was 2-4 × 10⁶ cells per brain; the plating efficiency was ≥70

  10. HIV-1 broadly neutralizing antibody precursor B cells revealed by germline-targeting immunogen.

    Science.gov (United States)

    Jardine, Joseph G; Kulp, Daniel W; Havenar-Daughton, Colin; Sarkar, Anita; Briney, Bryan; Sok, Devin; Sesterhenn, Fabian; Ereño-Orbea, June; Kalyuzhniy, Oleksandr; Deresa, Isaiah; Hu, Xiaozhen; Spencer, Skye; Jones, Meaghan; Georgeson, Erik; Adachi, Yumiko; Kubitz, Michael; deCamp, Allan C; Julien, Jean-Philippe; Wilson, Ian A; Burton, Dennis R; Crotty, Shane; Schief, William R

    2016-03-25

    Induction of broadly neutralizing antibodies (bnAbs) is a major HIV vaccine goal. Germline-targeting immunogens aim to initiate bnAb induction by activating bnAb germline precursor B cells. Critical unmet challenges are to determine whether bnAb precursor naïve B cells bind germline-targeting immunogens and occur at sufficient frequency in humans for reliable vaccine responses. Using deep mutational scanning and multitarget optimization, we developed a germline-targeting immunogen (eOD-GT8) for diverse VRC01-class bnAbs. We then used the immunogen to isolate VRC01-class precursor naïve B cells from HIV-uninfected donors. Frequencies of true VRC01-class precursors, their structures, and their eOD-GT8 affinities support this immunogen as a candidate human vaccine prime. These methods could be applied to germline targeting for other classes of HIV bnAbs and for Abs to other pathogens.

  11. Artificial and Natural Sialic Acid Precursors Influence the Angiogenic Capacity of Human Umbilical Vein Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Sebastian P. Galuska

    2013-02-01

    Full Text Available N-acetylneuraminic acid (Neu5Ac represents the most common terminal carbohydrate residue in many mammalian glycoconjugates and is directly involved in a number of different physiological as well as pathological cellular processes. Endogenous sialic acids derive from the biosynthetic precursor molecule N-acetyl-D-mannosamine (ManNAc. Interestingly, N-acyl-analogues of D-mannosamine (ManN can also be incorporated and converted into corresponding artificial sialic acids by eukaryotic cells. Within this study, we optimized a protocol for the chemical synthesis of various peracetylated ManN derivatives resulting in yields of approximately 100%. Correct molecular structures of the obtained products ManNAc, N-propanoyl-ManN (ManNProp and N-butyl-ManN (ManNBut were verified by GC-, ESI-MS- and NMR-analyses. By applying these substances to human umbilical vein endothelial cells (HUVECs, we could show that each derivative was metabolized to the corresponding N-acylneuraminic acid variant and subsequently incorporated into nascent glycoproteins. To investigate whether natural and/or artificial sialic acid precursors are able to modulate the angiogenic capacity of HUVECs, a spheroid assay was performed. By this means, an increase in total capillary length has been observed when cells incorporated N-butylneuraminic acid (Neu5But into their glycoconjugates. In contrast, the natural precursor ManNAc inhibited the growth of capillaries. Thus, sialic acid precursors may represent useful agents to modulate blood vessel formation.

  12. LINGO-1 negatively regulates myelination by oligodendrocytes.

    Science.gov (United States)

    Mi, Sha; Miller, Robert H; Lee, Xinhua; Scott, Martin L; Shulag-Morskaya, Svetlane; Shao, Zhaohui; Chang, Jufang; Thill, Greg; Levesque, Melissa; Zhang, Mingdi; Hession, Cathy; Sah, Dinah; Trapp, Bruce; He, Zhigang; Jung, Vincent; McCoy, John M; Pepinsky, R Blake

    2005-06-01

    The control of myelination by oligodendrocytes in the CNS is poorly understood. Here we show that LINGO-1 is an important negative regulator of this critical process. LINGO-1 is expressed in oligodendrocytes. Attenuation of its function by dominant-negative LINGO-1, LINGO-1 RNA-mediated interference (RNAi) or soluble human LINGO-1 (LINGO-1-Fc) leads to differentiation and increased myelination competence. Attenuation of LINGO-1 results in downregulation of RhoA activity, which has been implicated in oligodendrocyte differentiation. Conversely, overexpression of LINGO-1 leads to activation of RhoA and inhibition of oligodendrocyte differentiation and myelination. Treatment of oligodendrocyte and neuron cocultures with LINGO-1-Fc resulted in highly developed myelinated axons that have internodes and well-defined nodes of Ranvier. The contribution of LINGO-1 to myelination was verified in vivo through the analysis of LINGO-1 knockout mice. The ability to recapitulate CNS myelination in vitro using LINGO-1 antagonists and the in vivo effects seen in the LINGO-1 knockout indicate that LINGO-1 signaling may be critical for CNS myelination.

  13. Generation, Release, and Uptake of the NAD Precursor Nicotinic Acid Riboside by Human Cells.

    Science.gov (United States)

    Kulikova, Veronika; Shabalin, Konstantin; Nerinovski, Kirill; Dölle, Christian; Niere, Marc; Yakimov, Alexander; Redpath, Philip; Khodorkovskiy, Mikhail; Migaud, Marie E; Ziegler, Mathias; Nikiforov, Andrey

    2015-11-06

    NAD is essential for cellular metabolism and has a key role in various signaling pathways in human cells. To ensure proper control of vital reactions, NAD must be permanently resynthesized. Nicotinamide and nicotinic acid as well as nicotinamide riboside (NR) and nicotinic acid riboside (NAR) are the major precursors for NAD biosynthesis in humans. In this study, we explored whether the ribosides NR and NAR can be generated in human cells. We demonstrate that purified, recombinant human cytosolic 5'-nucleotidases (5'-NTs) CN-II and CN-III, but not CN-IA, can dephosphorylate the mononucleotides nicotinamide mononucleotide and nicotinic acid mononucleotide (NAMN) and thus catalyze NR and NAR formation in vitro. Similar to their counterpart from yeast, Sdt1, the human 5'-NTs require high (millimolar) concentrations of nicotinamide mononucleotide or NAMN for efficient catalysis. Overexpression of FLAG-tagged CN-II and CN-III in HEK293 and HepG2 cells resulted in the formation and release of NAR. However, NAR accumulation in the culture medium of these cells was only detectable under conditions that led to increased NAMN production from nicotinic acid. The amount of NAR released from cells engineered for increased NAMN production was sufficient to maintain viability of surrounding cells unable to use any other NAD precursor. Moreover, we found that untransfected HeLa cells produce and release sufficient amounts of NAR and NR under normal culture conditions. Collectively, our results indicate that cytosolic 5'-NTs participate in the conversion of NAD precursors and establish NR and NAR as integral constituents of human NAD metabolism. In addition, they point to the possibility that different cell types might facilitate each other's NAD supply by providing alternative precursors.

  14. Generation, Release, and Uptake of the NAD Precursor Nicotinic Acid Riboside by Human Cells*

    Science.gov (United States)

    Kulikova, Veronika; Shabalin, Konstantin; Nerinovski, Kirill; Dölle, Christian; Niere, Marc; Yakimov, Alexander; Redpath, Philip; Khodorkovskiy, Mikhail; Migaud, Marie E.; Ziegler, Mathias; Nikiforov, Andrey

    2015-01-01

    NAD is essential for cellular metabolism and has a key role in various signaling pathways in human cells. To ensure proper control of vital reactions, NAD must be permanently resynthesized. Nicotinamide and nicotinic acid as well as nicotinamide riboside (NR) and nicotinic acid riboside (NAR) are the major precursors for NAD biosynthesis in humans. In this study, we explored whether the ribosides NR and NAR can be generated in human cells. We demonstrate that purified, recombinant human cytosolic 5′-nucleotidases (5′-NTs) CN-II and CN-III, but not CN-IA, can dephosphorylate the mononucleotides nicotinamide mononucleotide and nicotinic acid mononucleotide (NAMN) and thus catalyze NR and NAR formation in vitro. Similar to their counterpart from yeast, Sdt1, the human 5′-NTs require high (millimolar) concentrations of nicotinamide mononucleotide or NAMN for efficient catalysis. Overexpression of FLAG-tagged CN-II and CN-III in HEK293 and HepG2 cells resulted in the formation and release of NAR. However, NAR accumulation in the culture medium of these cells was only detectable under conditions that led to increased NAMN production from nicotinic acid. The amount of NAR released from cells engineered for increased NAMN production was sufficient to maintain viability of surrounding cells unable to use any other NAD precursor. Moreover, we found that untransfected HeLa cells produce and release sufficient amounts of NAR and NR under normal culture conditions. Collectively, our results indicate that cytosolic 5′-NTs participate in the conversion of NAD precursors and establish NR and NAR as integral constituents of human NAD metabolism. In addition, they point to the possibility that different cell types might facilitate each other's NAD supply by providing alternative precursors. PMID:26385918

  15. Dual-specific Phosphatase-6 (Dusp6) and ERK Mediate AMPA Receptor-induced Oligodendrocyte Death*

    Science.gov (United States)

    Domercq, Maria; Alberdi, Elena; Sánchez-Gómez, Maria Victoria; Ariz, Usue; Pérez-Samartín, Alberto; Matute, Carlos

    2011-01-01

    Oligodendrocytes, the myelinating cells of the CNS, are highly vulnerable to glutamate excitotoxicity, a mechanism involved in tissue damage in multiple sclerosis. Thus, understanding oligodendrocyte death at the molecular level is important to develop new therapeutic approaches to treat the disease. Here, using microarray analysis and quantitative PCR, we observed that dual-specific phosphatase-6 (Dusp6), an extracellular regulated kinase-specific phosphatase, is up-regulated in oligodendrocyte cultures as well as in optic nerves after AMPA receptor activation. In turn, Dusp6 is overexpressed in optic nerves from multiple sclerosis patients before the appearance of evident damage in this structure. We further analyzed the role of Dusp6 and ERK signaling in excitotoxic oligodendrocyte death and observed that AMPA receptor activation induces a rapid increase in ERK1/2 phosphorylation. Blocking Dusp6 expression, which enhances ERK1/2 phosphorylation, significantly diminished AMPA receptor-induced oligodendrocyte death. In contrast, MAPK/ERK pathway inhibition with UO126 significantly potentiates excitotoxic oligodendrocyte death and increases cytochrome c release, mitochondrial depolarization, and mitochondrial calcium overload produced by AMPA receptor stimulation. Upstream analysis demonstrated that MAPK/ERK signaling alters AMPA receptor properties. Indeed, Dusp6 overexpression as well as incubation with UO126 produced an increase in AMPA receptor-induced inward currents and cytosolic calcium overload. Together, these data suggest that levels of phosphorylated ERK, controlled by Dusp6 phosphatase, regulate glutamate receptor permeability and oligodendroglial excitotoxicity. Therefore, targeting Dusp6 may be a useful strategy to prevent oligodendrocyte death in multiple sclerosis and other diseases involving CNS white matter. PMID:21300799

  16. Lead Poisoning Disturbs Oligodendrocytes Differentiation Involved in Decreased Expression of NCX3 Inducing Intracellular Calcium Overload

    Directory of Open Access Journals (Sweden)

    Teng Ma

    2015-08-01

    Full Text Available Lead (Pb poisoning has always been a serious health concern, as it permanently damages the central nervous system. Chronic Pb accumulation in the human body disturbs oligodendrocytes (OLs differentiation, resulting in dysmyelination, but the molecular mechanism remains unknown. In this study, Pb at 1 μM inhibits OLs precursor cells (OPCs differentiation via decreasing the expression of Olig 2, CNPase proteins in vitro. Moreover, Pb treatment inhibits the sodium/calcium exchanger 3 (NCX3 mRNA expression, one of the major means of calcium (Ca2+ extrusion at the plasma membrane during OPCs differentiation. Also addition of KB-R7943, NCX3 inhibitor, to simulate Pb toxicity, resulted in decreased myelin basic protein (MBP expression and cell branching. Ca2+ response trace with Pb and KB-R7943 treatment did not drop down in the same recovery time as the control, which elevated intracellular Ca2+ concentration reducing MBP expression. In contrast, over-expression of NCX3 in Pb exposed OPCs displayed significant increase MBP fluorescence signal in positive regions and CNPase expression, which recovered OPCs differentiation to counterbalance Pb toxicity. In conclusion, Pb exposure disturbs OLs differentiation via affecting the function of NCX3 by inducing intracellular calcium overload.

  17. Differentiation and selection of hepatocyte precursors in suspension spheroid culture of transgenic murine embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Elke Gabriel

    Full Text Available Embryonic stem cell-derived hepatocyte precursor cells represent a promising model for clinical transplantations to diseased livers, as well as for establishment of in vitro systems for drug metabolism and toxicology investigations. This study aimed to establish an in vitro culture system for scalable generation of hepatic progenitor cells. We used stable transgenic clones of murine embryonic stem cells possessing a reporter/selection vector, in which the enhanced green fluorescent protein- and puromycin N-acetyltransferase-coding genes are driven by a common alpha-fetoprotein gene promoter. This allowed for "live" monitoring and puromycin selection of the desired differentiating cell type possessing the activated alpha-fetoprotein gene. A rotary culture system was established, sequentially yielding initially partially selected hepatocyte lineage-committed cells, and finally, a highly purified cell population maintained as a dynamic suspension spheroid culture, which progressively developed the hepatic gene expression phenotype. The latter was confirmed by quantitative RT-PCR analysis, which showed a progressive up-regulation of hepatic genes during spheroid culture, indicating development of a mixed hepatocyte precursor-/fetal hepatocyte-like cell population. Adherent spheroids gave rise to advanced differentiated hepatocyte-like cells expressing hepatic proteins such as albumin, alpha-1-antitrypsin, cytokeratin 18, E-cadherin, and liver-specific organic anion transporter 1, as demonstrated by fluorescent immunostaining. A fraction of adherent cells was capable of glycogen storage and of reversible up-take of indocyanine green, demonstrating their hepatocyte-like functionality. Moreover, after transplantation of spheroids into the mouse liver, the spheroid-derived cells integrated into recipient. These results demonstrate that large-scale hepatocyte precursor-/hepatocyte-like cultures can be established for use in clinical trials, as well as in

  18. Skin-derived precursor cells promote wound healing in diabetic mice.

    Science.gov (United States)

    Sato, Hideyoshi; Ebisawa, Katsumi; Takanari, Keisuke; Yagi, Shunjiro; Toriyama, Kazuhiro; Yamawaki-Ogata, Aika; Kamei, Yuzuru

    2015-01-01

    Impaired wound healing as one of the complications arising from diabetes mellitus is a serious clinical issue. Recently, various cell therapies have been reported for promotion of wound healing. Skin-derived precursor cells (SKPs) are multipotent adult stem cells with the tendency to differentiate into neurons. We investigated the potency of promoting diabetic wound healing by the application of SKPs. Skin-derived precursor cells isolated from diabetic murine skin were cultured in sphere formation medium. At passage 2, they were suspended in phosphate-buffered saline (PBS), and applied topically to full-thickness excisional cutaneous wounds in diabetic mice. Application of PBS served as controls (n = 21 for each group; n = 42 total). Time to closure and percentage closure were calculated by morphometry. Wounds were harvested at 10 and 28 days and then processed, sectioned, and stained (CD31, α-smooth muscle actin, and neurofilament heavy chain) to quantify vascularity and neurofilaments. Wounds treated with SKPs demonstrated a significantly decreased time to closure (18.63 days) compared with PBS-control wounds (21.72 days, P wounds (P wounds at day 10 but not at day 28. Nerve Density (the number of neurofilaments/mm2) had increased significantly in SKP-treated wounds at day 28 compared with control group. Some applied SKPs were stained by neurofilament heavy chain, which demonstrates that SKPs directly differentiated into neurons. Skin-derived precursor cells promoted diabetic wound healings through vasculogenesis at the early stage of wound healing. Skin-derived precursor cells are a possible therapeutic tool for diabetic impaired wound healing.

  19. HEBAlt enhances the T-cell potential of fetal myeloid-biased precursors.

    Science.gov (United States)

    Braunstein, Marsela; Rajkumar, Paula; Claus, Carol L; Vaccarelli, Giovanna; Moore, Amanda J; Wang, Duncheng; Anderson, Michele K

    2010-12-01

    Hematopoiesis is controlled by the interplay between transcription factors and environmental signals. One of the primary determinants of the T-lineage choice is Delta-like (DL)-Notch signaling, which promotes T-cell development and inhibits B-cell development. We have found that the transcription factor HEBAlt is up-regulated in early hematopoietic precursors in response to DL-Notch signaling and that it can promote early T-cell development. Here, we identified a population of lineage-negative Sca-1⁻c-kit(+) (LK) cells in the mouse fetal liver that rapidly gave rise to myeloid cells and B cells but exhibited very little T-cell potential. However, forced expression of HEBAlt in these precursors restored their ability to develop into T cells. We also showed that Ikaros and Notch1 are up-regulated in response to HEBAlt over-expression and that activated Notch1 enhances the ability of LK cells to enter the T-cell lineage. Furthermore, the myeloid transcription factor C/EBPα is down-regulated in response to HEBAlt. We therefore propose that HEBAlt plays a role in the network that enforces the T-lineage fate and limits myeloid fate during hematopoiesis.

  20. Chondroitin Sulfate Proteoglycans Negatively Modulate Spinal Cord Neural Precursor Cells by Signaling Through LAR and RPTPσ and Modulation of the Rho/ROCK Pathway.

    Science.gov (United States)

    Dyck, Scott M; Alizadeh, Arsalan; Santhosh, Kallivalappil T; Proulx, Evan H; Wu, Chia-Lun; Karimi-Abdolrezaee, Soheila

    2015-08-01

    Multipotent adult neural precursor cells (NPCs) have tremendous intrinsic potential to repair the damaged spinal cord. However, evidence shows that the regenerative capabilities of endogenous and transplanted NPCs are limited in the microenvironment of spinal cord injury (SCI). We previously demonstrated that injury-induced upregulation of matrix chondroitin sulfate proteoglycans (CSPGs) restricts the survival, migration, integration, and differentiation of NPCs following SCI. CSPGs are long-lasting components of the astroglial scar that are formed around the lesion. Our recent in vivo studies demonstrated that removing CSPGs from the SCI environment enhances the potential of transplanted and endogenous adult NPCs for spinal cord repair; however, the mechanisms by which CSPGs regulate NPCs remain unclear. In this study, using in vitro models recapitulating the extracellular matrix of SCI, we investigated the direct role of CSPGs in modulating the properties of adult spinal cord NPCs. We show that CSPGs significantly decrease NPCs growth, attachment, survival, proliferation, and oligodendrocytes differentiation. Moreover, using genetic models, we show that CSPGs regulate NPCs by signaling on receptor protein tyrosine phosphate sigma (RPTPσ) and leukocyte common antigen-related phosphatase (LAR). Intracellularly, CSPGs inhibitory effects are mediated through Rho/ROCK pathway and inhibition of Akt and Erk1/2 phosphorylation. Downregulation of RPTPσ and LAR and blockade of ROCK in NPCs attenuates the inhibitory effects of CSPGS. Our work provide novel evidence uncovering how upregulation of CSPGs challenges the response of NPCs in their post-SCI niche and identifies new therapeutic targets for enhancing NPC-based therapies for SCI repair.

  1. Hypoxia Epigenetically Confers Astrocytic Differentiation Potential on Human Pluripotent Cell-Derived Neural Precursor Cells

    Directory of Open Access Journals (Sweden)

    Tetsuro Yasui

    2017-06-01

    Full Text Available Human neural precursor cells (hNPCs derived from pluripotent stem cells display a high propensity for neuronal differentiation, but they require long-term culturing to differentiate efficiently into astrocytes. The mechanisms underlying this biased fate specification of hNPCs remain elusive. Here, we show that hypoxia confers astrocytic differentiation potential on hNPCs through epigenetic gene regulation, and that this was achieved by cooperation between hypoxia-inducible factor 1α and Notch signaling, accompanied by a reduction of DNA methylation level in the promoter region of a typical astrocyte-specific gene, Glial fibrillary acidic protein. Furthermore, we found that this hypoxic culture condition could be applied to rapid generation of astrocytes from Rett syndrome patient-derived hNPCs, and that these astrocytes impaired neuronal development. Thus, our findings shed further light on the molecular mechanisms regulating hNPC differentiation and provide attractive tools for the development of therapeutic strategies for treating astrocyte-mediated neurological disorders.

  2. Adult Subependymal Neural Precursors, but Not Differentiated Cells, Undergo Rapid Cathodal Migration in the Presence of Direct Current Electric Fields

    OpenAIRE

    Robart Babona-Pilipos; Droujinine, Ilia A.; Popovic, Milos R.; Morshead, Cindi M.

    2011-01-01

    BACKGROUND: The existence of neural stem and progenitor cells (together termed neural precursor cells) in the adult mammalian brain has sparked great interest in utilizing these cells for regenerative medicine strategies. Endogenous neural precursors within the adult forebrain subependyma can be activated following injury, resulting in their proliferation and migration toward lesion sites where they differentiate into neural cells. The administration of growth factors and immunomodulatory age...

  3. Astrocytes in Oligodendrocyte Lineage Development and White Matter Pathology

    Science.gov (United States)

    Li, Jiasi; Zhang, Lei; Chu, Yongxin; Namaka, Michael; Deng, Benqiang; Kong, Jiming; Bi, Xiaoying

    2016-01-01

    White matter is primarily composed of myelin and myelinated axons. Structural and functional completeness of myelin is critical for the reliable and efficient transmission of information. White matter injury has been associated with the development of many demyelinating diseases. Despite a variety of scientific advances aimed at promoting re-myelination, their benefit has proven at best to be marginal. Research suggests that the failure of the re-myelination process may be the result of an unfavorable microenvironment. Astrocytes, are the most ample and diverse type of glial cells in central nervous system (CNS) which display multiple functions for the cells of the oligodendrocytes lineage. As such, much attention has recently been drawn to astrocyte function in terms of white matter myelin repair. They are different in white matter from those in gray matter in specific regards to development, morphology, location, protein expression and other supportive functions. During the process of demyelination and re-myelination, the functions of astrocytes are dynamic in that they are able to change functions in accordance to different time points, triggers or reactive pathways resulting in vastly different biologic effects. They have pivotal effects on oligodendrocytes and other cell types in the oligodendrocyte lineage by serving as an energy supplier, a participant of immunological and inflammatory functions, a source of trophic factors and iron and a sustainer of homeostasis. Astrocytic impairment has been shown to be directly linked to the development of neuromyelities optica (NMO). In addition, astroctyes have also been implicated in other white matter conditions such as psychiatric disorders and neurodegenerative diseases such as Alzheimer’s disease (AD), multiple sclerosis (MS) and amyotrophic lateral sclerosis (ALS). Inhibiting specifically detrimental signaling pathways in astrocytes while preserving their beneficial functions may be a promising approach for

  4. Astrocytes in oligodendrocyte lineage development and white matter pathology

    Directory of Open Access Journals (Sweden)

    Jiasi eLi

    2016-05-01

    Full Text Available White matter is primarily composed of myelin and myelinated axons. Structural and functional completeness of myelin is critical for the reliable and efficient transmission of information. White matter injury has been associated with the development of many demyelinating diseases. Despite a variety of scientific advances aimed at promoting re-myelination, their benefit has proven at best to be marginal. Research suggests that the failure of the re-myelination process may be the result of an unfavorable microenvironment. Astrocytes, are the most ample and diverse type of glial cells in central nervous system which display multiple functions for the cells of the oligodendrocytes lineage. As such, much attention has recently been drawn to astrocyte function in terms of white matter myelin repair. They are different in white matter from those in grey matter in specific regards to development, morphology, location, protein expression and other supportive functions. During the process of demyelination and re-myelination, the functions of astrocytes are dynamic in that they are able to change functions in accordance to different time points, triggers or reactive pathways resulting in vastly different biologic effects. They have pivotal effects on oligodendrocytes and other cell types in the oligodendrocyte lineage by serving as an energy supplier, a participant of immunological and inflammatory functions, a source of trophic factors and iron and a sustainer of homeostasis. Astrocytic impairment has been shown to be directly linked to the development of neuromyelities optica. In addition, astroctyes have also been implicated in other white matter conditions such as psychiatric disorders and neurodegenerative diseases such as Alzheimer’s disease, multiple sclerosis and amyotrophic lateral sclerosis. Inhibiting specifically detrimental signaling pathways in astrocytes while preserving their beneficial functions may be a promising approach for

  5. Lineage-Specific Genes Are Prominent DNA Damage Hotspots during Leukemic Transformation of B Cell Precursors

    Directory of Open Access Journals (Sweden)

    Bryant Boulianne

    2017-02-01

    Full Text Available In human leukemia, lineage-specific genes represent predominant targets of deletion, with lymphoid-specific genes frequently affected in lymphoid leukemia and myeloid-specific genes in myeloid leukemia. To investigate the basis of lineage-specific alterations, we analyzed global DNA damage in primary B cell precursors expressing leukemia-inducing oncogenes by ChIP-seq. We identified more than 1,000 sensitive regions, of which B lineage-specific genes constitute the most prominent targets. Identified hotspots at B lineage genes relate to DNA-DSBs, affect genes that harbor genomic lesions in human leukemia, and associate with ectopic deletion in successfully transformed cells. Furthermore, we show that most identified regions overlap with gene bodies of highly expressed genes and that induction of a myeloid lineage phenotype in transformed B cell precursors promotes de novo DNA damage at myeloid loci. Hence, we demonstrate that lineage-specific transcription predisposes lineage-specific genes in transformed B cell precursors to DNA damage, which is likely to promote the frequent alteration of lineage-specific genes in human leukemia.

  6. Nanodiamonds with silicon vacancy defects for non-toxic photostable fluorescent labeling of neural precursor cells

    CERN Document Server

    Merson, Tobias D; Aharonovich, Igor; Turbic, Alisa; Kilpatrick, Trevor J; Turnley, Ann M

    2013-01-01

    Nanodiamonds (NDs) containing silicon vacancy (SiV) defects were evaluated as a potential biomarker for the labeling and fluorescent imaging of neural precursor cells (NPCs). SiV-containing NDs were synthesized using chemical vapor deposition and silicon ion implantation. Spectrally, SiV-containing NDs exhibited extremely stable fluorescence and narrow bandwidth emission with an excellent signal to noise ratio exceeding that of NDs containing nitrogen-vacancy (NV) centers. NPCs labeled with NDs exhibited normal cell viability and proliferative properties consistent with biocompatibility. We conclude that SiVcontaining NDs are a promising biomedical research tool for cellular labeling and optical imaging in stem cell research.

  7. Ankfy1 is dispensable for neural stem/precursor cell development.

    Science.gov (United States)

    Weng, Chao; Ding, Man; Chang, Lian-Sheng; Ren, Ming-Xin; Zhang, Hong-Feng; Lu, Zu-Neng; Fu, Hui

    2016-11-01

    There are few studies on the membrane protein Ankfy1. We have found Ankfy1 is specifically expressed in neural stem/precursor cells during early development in mice (murine). To further explore Ankfy1 function in neural development, we developed a gene knockout mouse with a mixed Balb/C and C57/BL6 genetic background. Using immunofluorescence and in situ hybridization, neural defects were absent in mixed genetic Ankfy1 null mice during development and in adults up to 2 months old. However, Ankfy1 gene knockout mice with a pure genetic background were found to be lethal in the C57/BL6 inbred mice embryos, even after seven generations of backcrossing. Polymerase chain reaction confirmed homozygotes were unattainable as early as embryonic day 11.5. We conclude that Ankfy1 protein is dispensable in neural stem/precursor cells, but could be critical for early embryonic murine development, depending on the genetic background.

  8. Differentially activated macrophages orchestrate myogenic precursor cell fate during human skeletal muscle regeneration

    DEFF Research Database (Denmark)

    Saclier, Marielle; Yacoub-Youssef, Houda; Mackey, Abigail;

    2013-01-01

    Macrophages (MPs) exert either beneficial or deleterious effects on tissue repair, depending on their activation/polarization state. They are crucial for adult skeletal muscle repair, notably by acting on myogenic precursor cells. However, these interactions have not been fully characterized. Here......, we explored both in vitro and in vivo, in human, the interactions of differentially activated MPs with myogenic precursor cells (MPCs) during adult myogenesis and skeletal muscle regeneration. We showed in vitro that through the differential secretion of cytokines and growth factors, proinflammatory...... MPs inhibited MPC fusion while anti-inflammatory MPs strongly promoted MPC differentiation by increasing their commitment into differentiated myocytes and the formation of mature myotubes. Furthermore, the in vivo time course of expression of myogenic and MP markers was studied in regenerating human...

  9. Differentiation of endogenous neural precursors following spinal cord injury in adult rats

    Institute of Scientific and Technical Information of China (English)

    Bin Zhao; Hua Han; Shuanke Wang; Bingren Gao; Zhengyi Sun

    2008-01-01

    BACKGROUND:Studies have shown that cell death can activate proliferation of endogenous neural stem cells and promote newly generated cells to migrate to a lesion site.OBJECTIVE:To observe regeneration and differentiation of neural cells following spinal cord injury in adult rats and to quantitatively analyze the newly differentiated cells.DESIGN,TIME AND SETTING:A cell biology experiment was performed at the Institute of Orthopedics and Medical Experimental Center,Lanzhou University.between August 2005 and October 2007.MATERIALS:Fifty adult,Wistar rats of both sexes;5-bromodeoxyuridine(BrdU,Sigma,USA);antibodies against neuron-specific enolase,glial fibrillary acidic protein,and myelin basic protein(Chemicon,USA).METHODS:Twenty-five rats were assigned to the spinal cord injury group and received a spinal cord contusion injury.Materials were obtained at day 1,3,7,15,and 29 after injury,with 5 rats for each time point.Twenty-five rats were sham-treated by removing the lamina of the vertebral arch without performing a contusion.MAIN OUTCOME MEASURES:The phenotype of BrdU-labeled cells,i.e.,expression and distribution of surface markers for neurons(neuron-specific enolase),astrocytes(glial fibrillary acidic protein),and oligodendrocytes(myelin basic protein),were identified with immunofluorescence double-labeling.Confocal microscopy was used to detect double-labeled cells by immunofluorescence.Quantitative analysis of newly generated cells was performed with stereological counting methods.RESULTS:There was significant cell production and differentiation after adult rat spinal cord injury.The quantity of newly-generated BrdU-labeled cells in the spinal cord lesion was 75-fold greater than in the corresponding area of control animals.Endogenous neural precursor cells differentiated into astrocytes and oligodendrocytes,however spontaneous neuronal difierentiation was not detected.Between 7 and 29 d after spinal cord injury,newly generated cells expressed increasingly more

  10. Coordinated control of oligodendrocyte development by extrinsic and intrinsic signaling cues

    Institute of Scientific and Technical Information of China (English)

    Li He; Q.Richard Lu

    2013-01-01

    Oligodendrocytes,the myelin-forming cells for axon ensheathment in the central nervous system,are critical for maximizing and maintaining the conduction velocity of nerve impulses and proper brain function.Demyelination caused by injury or disease together with failure of myelin regeneration disrupts the rapid propagation of action potentials along nerve fibers,and is associated with acquired and inherited disorders,including devastating multiple sclerosis and leukodystrophies.The molecular mechanisms of oligodendrocyte myelination and remyelination remain poorly understood.Recently,a series of signaling pathways including Shh,Notch,BMP and Wnt signaling and their intracellular effectors such as Olig1/2,Hes1/5,Smads and TCFs,have been shown to play important roles in regulating oligodendrocyte development and myelination.In this review,we summarize our recent understanding of how these signaling pathways modulate the progression of oligodendrocyte specification and differentiation in a spatiotemporally-specific manner.A better understanding of the complex but coordinated function of extracellular signals and intracellular determinants during oligodendrocyte development will help to devise effective strategies to promote myelin repair for patients with demyelinating diseases.

  11. Movement and structure of mitochondria in oligodendrocytes and their myelin sheaths.

    Science.gov (United States)

    Rinholm, Johanne E; Vervaeke, Koen; Tadross, Michael R; Tkachuk, Ariana N; Kopek, Benjamin G; Brown, Timothy A; Bergersen, Linda H; Clayton, David A

    2016-05-01

    Mitochondria play several crucial roles in the life of oligodendrocytes. During development of the myelin sheath they are essential providers of carbon skeletons and energy for lipid synthesis. During normal brain function their consumption of pyruvate will be a key determinant of how much lactate is available for oligodendrocytes to export to power axonal function. Finally, during calcium-overload induced pathology, as occurs in ischemia, mitochondria may buffer calcium or induce apoptosis. Despite their important functions, very little is known of the properties of oligodendrocyte mitochondria, and mitochondria have never been observed in the myelin sheaths. We have now used targeted expression of fluorescent mitochondrial markers to characterize the location and movement of mitochondria within oligodendrocytes. We show for the first time that mitochondria are able to enter and move within the myelin sheath. Within the myelin sheath the highest number of mitochondria was in the cytoplasmic ridges along the sheath. Mitochondria moved more slowly than in neurons and, in contrast to their behavior in neurons and astrocytes, their movement was increased rather than inhibited by glutamate activating NMDA receptors. By electron microscopy we show that myelin sheath mitochondria have a low surface area of cristae, which suggests a low ATP production. These data specify fundamental properties of the oxidative phosphorylation system in oligodendrocytes, the glial cells that enhance cognition by speeding action potential propagation and provide metabolic support to axons. © 2016 Wiley Periodicals, Inc.

  12. Brief Report: Efficient Generation of Hematopoietic Precursors and Progenitors from Human Pluripotent Stem Cell Lines

    Science.gov (United States)

    Woods, Niels-Bjarne; Parker, Aaron S.; Moraghebi, Roksana; Lutz, Margaret K.; Firth, Amy L.; Brennand, Kristen J.; Berggren, W. Travis; Raya, Angel; Izpisúa Belmonte, Juan Carlos; Gage, Fred H.; Verma, Inder M.

    2012-01-01

    By mimicking embryonic development of the hematopoietic system, we have developed an optimized in vitro differentiation protocol for the generation of precursors of hematopoietic lineages and primitive hematopoietic cells from human embryonic stem cells (ESC) and induced pluripotent stem cells (iPSCs). Factors such as cytokines, extra cellular matrix components, and small molecules as well as the temporal association and concentration of these factors were tested on seven different human ESC and iPSC lines. We report the differentiation of up to 84% human CD45+ cells (average 41% ± 16%, from seven pluripotent lines) from the differentiation culture, including significant numbers of primitive CD45+/CD341 and CD45+/CD341/CD38− hematopoietic progenitors. Moreover, the numbers of hematopoietic progenitor cells generated, as measured by colony forming unit assays, were comparable to numbers obtained from fresh umbilical cord blood mononuclear cell isolates on a per CD45+ cell basis. Our approach demonstrates highly efficient generation of multipotent hematopoietic progenitors with among the highest efficiencies reported to date (CD45+/CD341) using a single standardized differentiation protocol on several human ESC and iPSC lines. Our data add to the cumulating evidence for the existence of an in vitro derived precursor to the hematopoietic stem cell (HSC) with limited engrafting ability in transplanted mice but with multipotent hematopoietic potential. Because this protocol efficiently expands the preblood precursors and hematopoietic progenitors, it is ideal for testing novel factors for the generation and expansion of definitive HSCs with long-term repopulating ability. PMID:21544903

  13. Brief report: efficient generation of hematopoietic precursors and progenitors from human pluripotent stem cell lines.

    Science.gov (United States)

    Woods, Niels-Bjarne; Parker, Aaron S; Moraghebi, Roksana; Lutz, Margaret K; Firth, Amy L; Brennand, Kristen J; Berggren, W Travis; Raya, Angel; Izpisúa Belmonte, Juan Carlos; Gage, Fred H; Verma, Inder M

    2011-07-01

    By mimicking embryonic development of the hematopoietic system, we have developed an optimized in vitro differentiation protocol for the generation of precursors of hematopoietic lineages and primitive hematopoietic cells from human embryonic stem cells (ESC) and induced pluripotent stem cells (iPSCs). Factors such as cytokines, extra cellular matrix components, and small molecules as well as the temporal association and concentration of these factors were tested on seven different human ESC and iPSC lines. We report the differentiation of up to 84% human CD45+ cells (average 41% ± 16%, from seven pluripotent lines) from the differentiation culture, including significant numbers of primitive CD45+/CD34+ and CD45+/CD34+/CD38- hematopoietic progenitors. Moreover, the numbers of hematopoietic progenitor cells generated, as measured by colony forming unit assays, were comparable to numbers obtained from fresh umbilical cord blood mononuclear cell isolates on a per CD45+ cell basis. Our approach demonstrates highly efficient generation of multipotent hematopoietic progenitors with among the highest efficiencies reported to date (CD45+/CD34+) using a single standardized differentiation protocol on several human ESC and iPSC lines. Our data add to the cumulating evidence for the existence of an in vitro derived precursor to the hematopoietic stem cell (HSC) with limited engrafting ability in transplanted mice but with multipotent hematopoietic potential. Because this protocol efficiently expands the preblood precursors and hematopoietic progenitors, it is ideal for testing novel factors for the generation and expansion of definitive HSCs with long-term repopulating ability.

  14. Efficient perovskite solar cells fabricated using an aqueous lead nitrate precursor.

    Science.gov (United States)

    Hsieh, Tsung-Yu; Wei, Tzu-Chien; Wu, Kuan-Lin; Ikegami, Masashi; Miyasaka, Tsutomu

    2015-09-04

    A novel, aqueous precursor system (Pb(NO3)2 + water) is developed to replace conventional (PbI2 + DMF) for fabricating methylammonium lead iodide (MAPbI3) perovskite solar cells (PSCs). When the morphology and surface coverage of the Pb(NO3)2 film was controlled during coating, a power conversion efficiency of 12.58% under standard conditions (AM1.5, 100 mW cm(-2)) was achieved for the PSC.

  15. CuInSe2 thin film solar cells synthesised from electrodeposited binary selenide precursors

    OpenAIRE

    Fischer, Johannes

    2012-01-01

    The box must contain a summary in a maximum of 1,700 characters, spaces included. The fabrication of a CuInSe2 thin film solar cell from an electrodeposited precursor stack consisting of indium selenide and copper selenide layers is demonstrated. A best conversion efficiency of 5.5% was achieved, a higher efficiency than previously reported in literature. The thesis focuses on three main parts: (i) electrochemistry of indium selenide: The incorporation of indium in the deposit require...

  16. Growth hormone responsive neural precursor cells reside within the adult mammalian brain

    OpenAIRE

    Blackmore, Daniel G.; Brent A. Reynolds; Golmohammadi, Mohammad G.; Large, Beatrice; Aguilar, Roberto M.; Haro, Luis; Waters, Michael J.; Rietze, Rodney L.

    2012-01-01

    The detection of growth hormone (GH) and its receptor in germinal regions of the mammalian brain prompted our investigation of GH and its role in the regulation of endogenous neural precursor cell activity. Here we report that the addition of exogenous GH significantly increased the expansion rate in long-term neurosphere cultures derived from wild-type mice, while neurospheres derived from GH null mice exhibited a reduced expansion rate. We also detected a doubling in the frequency of large ...

  17. "The Correlation between the Percent of CD3- CD56+ Cells and NK Precursor Function "

    Directory of Open Access Journals (Sweden)

    Ahmad Gharehbaghian

    2006-12-01

    Full Text Available The number and function of human natural killer (NK cells are generally assessed to monitor the baseline of immune function, the effect of treatment, the progress of malignancy or metastases and diseases. NK cells recognise and kill target cells in the absence of prior sensitisation and are able to defend the host from infection or prevent the progression of a disease. Human NK cells express CD16 and CD56 which are (massively being used as a major hallmark for the NK cell. The purpose of this study was to identify the unique subsets of peripheral blood mononuclear cells (PBMC (%CD3-CD56+ cells by flow cytometry and to determine whether there is any correlation with functionally mature progeny of (NKp precursor after five days of culture. The correlation was analysed using samples obtained from 120 Caucasian patients. 20-30ml of whole blood was collected in sterile tube containing preservative free sodium heparin and a similar sample was obtained after five days. Maturation of NKp required the continuous presence of recombinant interleukin 2 (rIL-2, or interleukin 15 (rIL-15 and functional maturity of NK cells was determined by their ability to lyse target cells from the K562 cell line. The NK precursor frequency was measured by limiting dilution analysis (LDA, which The NKpf assay was set up with a range of cell dilutions from 40,000 to 625 per 100l/well in 96 well culture plates. At the end of the culture period the K562 cell line labelled with Europium (Eu-K562 was added and Eu release measured in culture supernatants using time-resolved fluorometry. The PBMC were set up in parallel cultures under various conditions .On day five cells were collected from culture plates and adjusted to 1x10 cells/ml and then mixed. The mixture was incubated and anti CD3 and anti CD56 were added. NK cells were enumerated in 120 patients by double staining with a combination of anti-CD3- and anti-CD56+. The results of these Immunophenotyping studies by flow

  18. Cyclooxygenase-2 expression in oligodendrocytes increases sensitivity to excitotoxic death

    Directory of Open Access Journals (Sweden)

    Rojas Monica A

    2010-04-01

    Full Text Available Abstract Background We previously found that cyclooxygenase 2 (COX-2 was expressed in dying oligodendrocytes at the onset of demyelination in the Theiler's murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD model of multiple sclerosis (MS (Carlson et al. J.Neuroimmunology 2006, 149:40. This suggests that COX-2 may contribute to death of oligodendrocytes. Objective The goal of this study was to examine whether COX-2 contributes to excitotoxic death of oligodendrocytes and potentially contributes to demyelination. Methods The potential link between COX-2 and oligodendrocyte death was approached using histopathology of MS lesions to examine whether COX-2 was expressed in dying oligodendrocytes. COX-2 inhibitors were examined for their ability to limit demyelination in the TMEV-IDD model of MS and to limit excitotoxic death of oligodendrocytes in vitro. Genetic manipulation of COX-2 expression was used to determine whether COX-2 contributes to excitotoxic death of oligodendrocytes. A transgenic mouse line was generated that overexpressed COX-2 in oligodendrocytes. Oligodendrocyte cultures derived from these transgenic mice were used to examine whether increased expression of COX-2 enhanced the vulnerability of oligodendrocytes to excitotoxic death. Oligodendrocytes derived from COX-2 knockout mice were evaluated to determine if decreased COX-2 expression promotes a greater resistance to excitotoxic death. Results COX-2 was expressed in dying oligodendrocytes in MS lesions. COX-2 inhibitors limited demyelination in the TMEV-IDD model of MS and protected oligodendrocytes against excitotoxic death in vitro. COX-2 expression was increased in wild-type oligodendrocytes following treatment with Kainic acid (KA. Overexpression of COX-2 in oligodendrocytes increased the sensitivity of oligodendrocytes to KA-induced excitotoxic death eight-fold compared to wild-type. Conversely, oligodendrocytes prepared from COX-2 knockout mice showed a

  19. Zinc Deficiency Induces Apoptosis via Mitochondrial p53- and Caspase-Dependent Pathways in Human Neuronal Precursor Cells

    Science.gov (United States)

    Seth, Rohit; Corniola, Rikki S.; Gower-Winter, Shannon D.; Morgan, Thomas J., Jr.; Bishop, Brian; Levenson, Cathy W.

    2015-01-01

    Previous studies have shown that zinc deficiency leads to apoptosis of neuronal precursor cells in vivo and in vitro. In addition to the role of p53 as a nuclear transcription factor in zinc deficient cultured human neuronal precursors (NT-2), we have now identified the translocation of phosphorylated p53 to the mitochondria and p53-dependent…

  20. β-Amyloid precursor protein: function in stem cell development and Alzheimer's disease brain.

    Science.gov (United States)

    Small, David H; Hu, Yanling; Bolós, Marta; Dawkins, Edgar; Foa, Lisa; Young, Kaylene M

    2014-01-01

    Stem cell therapy may be a suitable approach for the treatment of many neurodegenerative diseases. However, one major impediment to the development of successful cell-based therapies is our limited understanding of the mechanisms that instruct neural stem cell behaviour, such as proliferation and cell fate specification. The β-amyloid precursor protein (APP) of Alzheimer's disease (AD) may play an important role in neural stem cell proliferation and differentiation. Our recent work shows that in vitro, APP stimulates neural stem or progenitor cell proliferation and neuronal differentiation. The effect on proliferation is mediated by an autocrine factor that we have identified as cystatin C. As cystatin C expression is also reported to inhibit the development of amyloid pathology in APP transgenic mice, our finding has implications for the possible use of cystatin C for the therapy of AD.

  1. Oligodendrocyte, Astrocyte, and Microglia Crosstalk in Myelin Development, Damage, and Repair

    Science.gov (United States)

    Domingues, Helena S.; Portugal, Camila C.; Socodato, Renato; Relvas, João B.

    2016-01-01

    Oligodendrocytes are the myelinating glia of the central nervous system. Myelination of axons allows rapid saltatory conduction of nerve impulses and contributes to axonal integrity. Devastating neurological deficits caused by demyelinating diseases, such as multiple sclerosis, illustrate well the importance of the process. In this review, we focus on the positive and negative interactions between oligodendrocytes, astrocytes, and microglia during developmental myelination and remyelination. Even though many lines of evidence support a crucial role for glia crosstalk during these processes, the nature of such interactions is often neglected when designing therapeutics for repair of demyelinated lesions. Understanding the cellular and molecular mechanisms underlying glial cell communication and how they influence oligodendrocyte differentiation and myelination is fundamental to uncover novel therapeutic strategies for myelin repair. PMID:27551677

  2. Secretory clusterin inhibits osteoclastogenesis by attenuating M-CSF-dependent osteoclast precursor cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Bongkun; Kang, Soon-Suk [Department of Biomedical Sciences, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Kang, Sang-Wook [Department of Biomedical Sciences, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Department of Anatomy and Cell Biology, Cell Dysfunction Research Center and BMIT, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Min, Bon-Hong [Department of Pharmacology, Korea University College of Medicine, Seoul 136-705 (Korea, Republic of); Lee, Eun-Jin; Song, Da-Hyun; Kim, Sang-Min [Department of Biomedical Sciences, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Song, Youngsup [Department of Biomedical Sciences, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Department of Anatomy and Cell Biology, Cell Dysfunction Research Center and BMIT, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Yoon, Seung-Yong [Department of Anatomy and Cell Biology, Cell Dysfunction Research Center and BMIT, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Chang, Eun-Ju, E-mail: ejchang@amc.seoul.kr [Department of Biomedical Sciences, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of); Department of Anatomy and Cell Biology, Cell Dysfunction Research Center and BMIT, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of)

    2014-07-18

    Highlights: • We describe the expression and secretion of clusterin in osteoclasts. • Endogenous clusterin deficiency does not affect osteoclast formation. • Exogenous treatment with secretory clusterin decreases osteoclast differentiation. • Secretory clusterin attenuates osteoclast precursor cell proliferation by inhibiting M-CSF-mediated ERK activation. - Abstract: Secretory clusterin (sCLU)/apolipoprotein J is a multifunctional glycoprotein that is ubiquitously expressed in various tissues. Reduced sCLU in the joints of patients with bone erosive disease is associated with disease activity; however, its exact role has yet to be elucidated. Here, we report that CLU is expressed and secreted during osteoclastogenesis in mouse bone marrow-derived macrophages (BMMs) that are treated with receptor activator of nuclear factor kappa-B ligand (RANKL) and macrophage colony-stimulating factor (M-CSF). CLU-deficient BMMs obtained from CLU{sup −/−} mice exhibited no significant alterations in OC differentiation in comparison with BMMs obtained from wild-type mice. In contrast, exogenous sCLU treatment significantly inhibited OC formation in both BMMs and OC precursor cultures. The inhibitory effect of sCLU was more prominent in BMMs than OC precursor cultures. Interestingly, treating BMMs with sCLU decreased the proliferative effects elicited by M-CSF and suppressed M-CSF-induced ERK activation of OC precursor cells without causing apoptotic cell death. This study provides the first evidence that sCLU reduces OC formation by inhibiting the actions of M-CSF, thereby suggesting its protective role in bone erosion.

  3. Role of Sonic Hedgehog Signaling in Oligodendrocyte Differentiation.

    Science.gov (United States)

    Wang, Li-Chun; Almazan, Guillermina

    2016-12-01

    During development, the secreted molecule Sonic Hedgehog (Shh) is required for lineage specification and proliferation of oligodendrocyte progenitors (OLPs), which are the glia cells responsible for the myelination of axons in the central nervous system (CNS). Shh signaling has been implicated in controlling both the generation of oligodendrocytes (OLGs) during embryonic development and their production in adulthood. Although, some evidence points to a role of Shh signaling in OLG development, its involvement in OLG differentiation remains to be fully determined. The objective of this study was to assess whether Shh signaling is involved in OLG differentiation after neural stem cell commitment to the OLG lineage. To address these questions, we manipulated Shh signaling using cyclopamine, a potent inhibitor of Shh signaling activator Smoothened (Smo), alone or combined with the agonist SAG in OLG primary cultures and assessed expression of myelin-specific markers. We found that inactivation of Shh signaling caused a dose-dependent decrease in myelin basic protein (MBP) and myelin associated glycoprotein (MAG) in differentiating OLGs. Co-treatment of the cells with SAG reversed the inhibitory effect of cyclopamine on both myelin-specific protein levels and morphological changes associated with it. Further experiments are required to elucidate the molecular mechanism by which Shh signaling regulates OLG differentiation.

  4. Migration of R28 Retinal Precursor Cells into Cochlear and Vestibular Organs

    Institute of Scientific and Technical Information of China (English)

    DING Dalian; Gail Seigel; Richard Salvi

    2006-01-01

    Damaged hair cells and neurons in the inner ear generally can not be replaced in mammals. The loss of these cells causes permanent functional disorders in both the cochlear and vestibular systems. Transplantation of retinal precursor cells, R28 cells, into inner ear tissue may help replace missing cells. The aim of the current project was to induce R28 cell transdifferentiation into cochlear and vestibular cell types under culture conditions. The first part was related to R28 cell labeling with DiI fluorescence that would help identify and track R28 cells. The second part involved co-culturing R28 cells in cochlear and vestibular organotropic cultures or isolated spiral ganglion neurons. The results suggest that R28 cells have the potential to differentiate into supporting cell types and spiral ganglion neurons in serum free medium, probably under the influence of diffusible signals from inner ear tissues. This information is useful for future efforts in inducing stem cell differentiation in the inner ear to replace lost sensory and neural cells.

  5. Msx genes define a population of mural cell precursors required for head blood vessel maturation.

    Science.gov (United States)

    Lopes, Miguel; Goupille, Olivier; Saint Cloment, Cécile; Lallemand, Yvan; Cumano, Ana; Robert, Benoît

    2011-07-01

    Vessels are primarily formed from an inner endothelial layer that is secondarily covered by mural cells, namely vascular smooth muscle cells (VSMCs) in arteries and veins and pericytes in capillaries and veinules. We previously showed that, in the mouse embryo, Msx1(lacZ) and Msx2(lacZ) are expressed in mural cells and in a few endothelial cells. To unravel the role of Msx genes in vascular development, we have inactivated the two Msx genes specifically in mural cells by combining the Msx1(lacZ), Msx2(lox) and Sm22α-Cre alleles. Optical projection tomography demonstrated abnormal branching of the cephalic vessels in E11.5 mutant embryos. The carotid and vertebral arteries showed an increase in caliber that was related to reduced vascular smooth muscle coverage. Taking advantage of a newly constructed Msx1(CreERT2) allele, we demonstrated by lineage tracing that the primary defect lies in a population of VSMC precursors. The abnormal phenotype that ensues is a consequence of impaired BMP signaling in the VSMC precursors that leads to downregulation of the metalloprotease 2 (Mmp2) and Mmp9 genes, which are essential for cell migration and integration into the mural layer. Improper coverage by VSMCs secondarily leads to incomplete maturation of the endothelial layer. Our results demonstrate that both Msx1 and Msx2 are required for the recruitment of a population of neural crest-derived VSMCs.

  6. Pathogenesis of myelin/oligodendrocyte damage in multiple sclerosis.

    Science.gov (United States)

    Dhib-Jalbut, Suhayl

    2007-05-29

    Substantial evidence supports autoimmune activity as the etiologic mechanism underlying multiple sclerosis (MS). Both the innate and the adaptive arms of the immune system are involved in the aberrant response to several antigens associated with the myelin sheath and oligodendrocytes (OGCs) after the activation of immune cells by self- or cross-reactive microbial pathogens. The CD4(+) Th1 cell, in particular, has been implicated, but it is abetted by a variety of other cell types (CD8(+) cells, B cells, macrophages, and microglia) and soluble products (proteases, cytokines, and nitric oxide [NO]) that act both outside of and within the CNS. This review describes recent and salient findings from animal models and human clinical studies that have established our current understanding of the distinct steps in the development of immune autoreactivity that culminates in the CNS lesions associated with MS.

  7. The jasmonate precursor, 12-oxo-phytodienoic acid, induces phytoalexin synthesis in Petroselinum crispum cell cultures.

    Science.gov (United States)

    Dittrich, H; Kutchan, T M; Zenk, M H

    1992-08-31

    The pentacyclic biosynthetic precursor of jasmonic acid, 12-oxo-phytodienoic acid, was found to induce synthesis of the major flavonoid, apiin, in cell suspension cultures of Petroselinum crispum. The accumulation of apiin was preceded by an increase in the relative levels of poly (A)+ RNAs that code for the flavonoid biosynthetic enzymes phenylalanine ammonia lyase, 4-coumarate:CoA ligase and chalcone synthase, Poly (A)+ RNAs reached maximal levels at approximately 4-6 h after the addition of elicitor while flavonoids continued to accumulate in the cultures for at least 6 days. 12-Oxo-phytodienoic acid is the first pentacyclic precursor in the jasmonic acid biosynthetic chain which functions as a signal transducer for phytoalexin induction.

  8. Ion channel expression by white matter glia: I. Type 2 astrocytes and oligodendrocytes.

    Science.gov (United States)

    Barres, B A; Chun, L L; Corey, D P

    1988-01-01

    White matter is a compact structure consisting primarily of neuronal axons and glial cells. As in other parts of the nervous system, the function of glial cells in white matter is poorly understood. We have explored the electrophysiological properties of two types of glial cells found predominantly in white matter: type 2 astrocytes and oligodendrocytes. Whole-cells and single-channel patch-clamp techniques were used to study these cell types in postnatal rat optic nerve cultures prepared according to the procedures of Raff et al. (Nature, 303:390-396, 1983b). Type 2 astrocytes in culture exhibit a "neuronal" channel phenotype, expressing at least six distinct ion channel types. With whole-cell recording we observed three inward currents: a voltage-sensitive sodium current qualitatively similar to that found in neurons and both transient and sustained calcium currents. In addition, type 2 astrocytes had two components of outward current: a delayed potassium current which activated at 0 mV and an inactivating calcium-dependent potassium current which activated at -30 mV. Type 2 astrocytes in culture could be induced to fire single regenerative potentials in response to injections of depolarizing current. Single-channel recording demonstrated the presence of an outwardly rectifying chloride channel in both type 2 astrocytes and oligodendrocytes, but this channel could only be observed in excised patches. Oligodendrocytes expressed only one other current: an inwardly rectifying potassium current that is mediated by 30- and 120-pS channels. Because these channels preferentially conduct potassium from outside to inside the cell, and because they are open at the resting potential of the cell, they would be appropriate for removing potassium from the extracellular space; thus it is proposed that oligodendrocytes, besides myelinating axons, play an important role in potassium regulation in white matter. The conductances present in oligodendrocytes suggest a "modulated

  9. STUDY ON DIFFERENTIATION OF RATS EMBRYONIC STEM CELLS CULTURED IN BRL-CM INTO NEURAL PRECURSOR CELLS

    Institute of Scientific and Technical Information of China (English)

    张晓智; 李旭; 徐海伟; 陈葳

    2003-01-01

    Objective To investigate whether buffalo rat liver cell-conditioned medium (BRL-CM) can be used as the culture medium of embryonic stem (ES) cells, and to get relatively pure neural precursor cells (NPCs) for treatment aim. Methods Mouse ES cells were cultured in BRL-CM and medium contain leukemia inhibitory factor (LIF), respectively. NPCs were selectively cultured in serum-free medium. Alkaline phosphatase activity was visualized with NBT/BCIP and nestin antigen was detected with immunocytochemical methods. Results BRL-CM could be used as an efficiency culture condition instead of LIF in ES cells culture. About 86% of cells derived from ES cells in the serum-free culture were NPCs. Conclusion BRL-CM can replace LIF to use in ES cell culture. High purity of NPC can be induced from ES cells with serum-free culture method.

  10. Schwann cells originating from skin-derived precursors promote peripheral nerve regeneration in rats

    Institute of Scientific and Technical Information of China (English)

    Ping Zhang; Xiaocheng Lu; Jianghai Chen; Zhenbing Chen

    2014-01-01

    Artiifcial guidance channels containing Schwann cells can promote the regeneration of injured peripheral nerve over long distances. However, primary Schwann cells are not suitable for autotransplantation. Under speciifc conditions, skin-derived progenitors can be induced to dif-ferentiate into Schwann cells. Therefore, adult rat dorsal skin (dermis)-derived progenitors were isolated and induced to differentiate with DMEM/F12 containing B27, neuregulin 1, and for-skolin. Immunolfuorescence staining and reverse transcription polymerase chain reaction (RT-PCR) conifrmed that the resultant cells were indeed Schwann cells. Artiifcial guidance channels containing skin-derived progenitors, Schwann cells originating from skin-derived progenitors, or primary Schwann cells were used to bridge 5 mm sciatic nerve defects. Schwann cells originating from skin-derived progenitors signiifcantly promoted sciatic nerve axonal regeneration. The sig-niifcant recovery of injured rat sciatic nerve function after the transplantation of Schwann cells originating from skin-derived progenitors was conifrmed by electromyogram. The therapeutic effect of Schwann cells originating from skin-derived progenitors was better than that of skin-de-rived progenitors. These findings indicate that Schwann cells originating from skin-derived precursors can promote peripheral nerve regeneration in rats.

  11. Immunocytochemical study with an anti-transferrin binding protein serum: a marker for avian oligodendrocytes.

    Science.gov (United States)

    Cho, S S; Lucas, J J

    1995-03-13

    We have investigated immunocytochemically the localization of a transferrin binding protein (TfBP) in adult CNS of avian and mammalian species using a polyclonal antibody raised against the protein purified from hen oviduct membranes (alpha OV-TfBP). TfBP has recently been shown to be HSP108. An overall strong immunoreactivity was revealed in most parts of the avian brains, especially in the white matter. The main immunoreactivity originated in small, intensely reacting cells interpreted as oligodendrocytes. The density of TfBP-labeled oligodendrocytes of the avian brains was generally proportional to the degree of myelination. There were no marked differences in TfBP-immunostaining pattern between avian species (chick, pigeon and lovebird). On the other hand, in rat, rabbit and cat brains we could not find any TfBP-immunoreactivity. Immunoelectron microscopy has further revealed that TfBP is present in the light and medium types of oligodendrocytes which are known to have high metabolic activities. TfBP reaction product was homogeneously dispersed throughout the perinuclear cytoplasm and fine processes of oligodendrocytes. The intracytoplasmic organelles such as mitochondria and Golgi apparatus were devoid of reaction product. The presence of TfBP in oligodendrocytes implies that this protein may play an important role in transferrin-mediated iron metabolism in the CNS. The complete lack of cross-reactivity between alpha OV-TfBP and mammalian tissues suggests that there is species variability in TfBP structure. We conclude that this chick TfBP antiserum will prove useful in studies of oligodendrocytes and myelination in the avian CNS.

  12. The lantibiotic NAI-107 binds to bactoprenol-bound cell wall precursors and impairs membrane functions.

    Science.gov (United States)

    Münch, Daniela; Müller, Anna; Schneider, Tanja; Kohl, Bastian; Wenzel, Michaela; Bandow, Julia Elisabeth; Maffioli, Sonia; Sosio, Margherita; Donadio, Stefano; Wimmer, Reinhard; Sahl, Hans-Georg

    2014-04-25

    The lantibiotic NAI-107 is active against Gram-positive bacteria including vancomycin-resistant enterococci and methicillin-resistant Staphylococcus aureus. To identify the molecular basis of its potency, we studied the mode of action in a series of whole cell and in vitro assays and analyzed structural features by nuclear magnetic resonance (NMR). The lantibiotic efficiently interfered with late stages of cell wall biosynthesis and induced accumulation of the soluble peptidoglycan precursor UDP-N-acetylmuramic acid-pentapeptide (UDP-MurNAc-pentapeptide) in the cytoplasm. Using membrane preparations and a complete cascade of purified, recombinant late stage peptidoglycan biosynthetic enzymes (MraY, MurG, FemX, PBP2) and their respective purified substrates, we showed that NAI-107 forms complexes with bactoprenol-pyrophosphate-coupled precursors of the bacterial cell wall. Titration experiments indicate that first a 1:1 stoichiometric complex occurs, which then transforms into a 2:1 (peptide: lipid II) complex, when excess peptide is added. Furthermore, lipid II and related molecules obviously could not serve as anchor molecules for the formation of defined and stable nisin-like pores, however, slow membrane depolarization was observed after NAI-107 treatment, which could contribute to killing of the bacterial cell.

  13. Adaptive peripheral immune response increases proliferation of neural precursor cells in the adult hippocampus.

    Science.gov (United States)

    Wolf, Susanne A; Steiner, Barbara; Wengner, Antje; Lipp, Martin; Kammertoens, Thomas; Kempermann, Gerd

    2009-09-01

    To understand the link between peripheral immune activation and neuronal precursor biology, we investigated the effect of T-cell activation on adult hippocampal neurogenesis in female C57Bl/6 mice. A peripheral adaptive immune response triggered by adjuvant-induced rheumatoid arthritis (2 microg/microl methylated BSA) or staphylococcus enterotoxin B (EC(50) of 0.25 microg/ml per 20 g body weight) was associated with a transient increase in hippocampal precursor cell proliferation and neurogenesis as assessed by immunohistochemistry and confocal microscopy. Both treatments were paralleled by an increase in corticosterone levels in the hippocampus 1- to 2-fold over the physiological amount measured by quantitative radioimmunoassay. In contrast, intraperitoneal administration of the innate immune response activator lipopolysaccaride (EC(50) of 0.5 microg/ml per 20 g body weight) led to a chronic 5-fold increase of hippocampal glucocorticoid levels and a decrease of adult neurogenesis. In vitro exposure of murine neuronal progenitor cells to corticosterone triggered either cell death at high (1.5 nM) or proliferation at low (0.25 nM) concentrations. This effect could be blocked using a viral vector system expressing a transdomain of the glucocorticoid receptor. We suggest an evolutionary relevant communication route for the brain to respond to environmental stressors like inflammation mediated by glucocorticoid levels in the hippocampus.

  14. Characterization of the murine myeloid precursor cell line MuMac-E8.

    Science.gov (United States)

    Fricke, Stephan; Pfefferkorn, Cathleen; Wolf, Doris; Riemschneider, Sina; Kohlschmidt, Janine; Hilger, Nadja; Fueldner, Christiane; Knauer, Jens; Sack, Ulrich; Emmrich, Frank; Lehmann, Jörg

    2014-01-01

    Starting point for the present work was the assumption that the cell line MuMac-E8 represents a murine cell population with stem cell properties. Preliminary studies already pointed to the expression of stem-cell associated markers and a self-regenerative potential of the cells. The cell line MuMac-E8 should be examined for their differential stage within stem cell hierarchy. MuMac-E8 cells were derived from a chimeric mouse model of arthritis. It could be shown that MuMac-E8 cells express mRNA of some genes associated with pluripotent stem cells (Nanog, Nucleostemin), of genes for hematopoietic markers (EPCR, Sca-1, CD11b, CD45), for the mesenchymal marker CD105 and of genes for the neural markers Pax-6 and Ezrin. In methylcellulose and May-Grünwald-Giemsa staining, hematopoietic colonies were obtained but the hematopoietic system of lethally irradiated mice could not be rescued. Osteogenic differentiation was not detectable. Thus, it became evident that MuMac-E8 represents not a stem cell line. However, MuMac-E8 cells expressed several myeloid surface markers (i.e. CD11b, F4/80, CD14, CD64), showed phagocytosis and is capable of producing nitric oxide. Thus, this cell line seems to be arrested an advanced stage of myeloid differentiation. Adherence data measured by impedance-based real-time cell analysis together with cell morphology data suggested that MuMac-E8 represents a new macrophage precursor cell line exhibiting weak adherence. This cell line is suitable as an in-vitro model for testing of macrophage functions. Moreover, it might be also useful for differentiation or reprogramming studies.

  15. Characterization of the murine myeloid precursor cell line MuMac-E8.

    Directory of Open Access Journals (Sweden)

    Stephan Fricke

    Full Text Available Starting point for the present work was the assumption that the cell line MuMac-E8 represents a murine cell population with stem cell properties. Preliminary studies already pointed to the expression of stem-cell associated markers and a self-regenerative potential of the cells. The cell line MuMac-E8 should be examined for their differential stage within stem cell hierarchy. MuMac-E8 cells were derived from a chimeric mouse model of arthritis. It could be shown that MuMac-E8 cells express mRNA of some genes associated with pluripotent stem cells (Nanog, Nucleostemin, of genes for hematopoietic markers (EPCR, Sca-1, CD11b, CD45, for the mesenchymal marker CD105 and of genes for the neural markers Pax-6 and Ezrin. In methylcellulose and May-Grünwald-Giemsa staining, hematopoietic colonies were obtained but the hematopoietic system of lethally irradiated mice could not be rescued. Osteogenic differentiation was not detectable. Thus, it became evident that MuMac-E8 represents not a stem cell line. However, MuMac-E8 cells expressed several myeloid surface markers (i.e. CD11b, F4/80, CD14, CD64, showed phagocytosis and is capable of producing nitric oxide. Thus, this cell line seems to be arrested an advanced stage of myeloid differentiation. Adherence data measured by impedance-based real-time cell analysis together with cell morphology data suggested that MuMac-E8 represents a new macrophage precursor cell line exhibiting weak adherence. This cell line is suitable as an in-vitro model for testing of macrophage functions. Moreover, it might be also useful for differentiation or reprogramming studies.

  16. Zn2+ -induced ERK activation mediates PARP-1-dependent ischemic-reoxygenation damage to oligodendrocytes.

    Science.gov (United States)

    Domercq, Maria; Mato, Susana; Soria, Federico N; Sánchez-gómez, M Victoria; Alberdi, Elena; Matute, Carlos

    2013-03-01

    Much of the cell death following episodes of anoxia and ischemia in the mammalian central nervous system has been attributed to extracellular accumulation of glutamate and ATP, which causes a rise in [Ca(2+)](i), loss of mitochondrial potential, and cell death. However, restoration of blood flow and reoxygenation are frequently associated with exacerbation of tissue injury (the oxygen paradox). Herein we describe a novel signaling pathway that is activated during ischemia-like conditions (oxygen and glucose deprivation; OGD) and contributes to ischemia-induced oligodendroglial cell death. OGD induced a retarded and sustained increase in extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation after restoring glucose and O(2) (reperfusion-like conditions). Blocking the ERK1/2 pathway with the MEK inhibitor UO126 largely protected oligodendrocytes against ischemic insults. ERK1/2 activation was blocked by the high-affinity Zn(2+) chelator TPEN, but not by antagonists of AMPA/kainate or P2X7 receptors that were previously shown to be involved in ischemic oligodendroglial cell death. Using a high-affinity Zn(2+) probe, we showed that ischemia induced an intracellular Zn(2+) rise in oligodendrocytes, and that incubation with TPEN prevented mitochondrial depolarization and ROS generation after ischemia. Accordingly, exposure to TPEN and the antioxidant Trolox reduced ischemia-induced oligodendrocyte death. Moreover, UO126 blocked the ischemia-induced increase in poly-[ADP]-ribosylation of proteins, and the poly[ADP]-ribose polymerase 1 (PARP-1) inhibitor DPQ significantly inhibited ischemia-induced oligodendroglial cell death-demonstrating that PARP-1 was required downstream in the Zn(2+)-ERK oligodendrocyte cell death pathway. Chelation of cytosolic Zn(2+), blocking ERK signaling, and antioxidants may be beneficial for treating CNS white matter ischemia-reperfusion injury. Importantly, all the inhibitors of this pathway protected oligodendrocytes when applied

  17. Exposure of CD34+ precursors to cytostatic anthraquinone-derivatives induces rapid dendritic cell differentiation: implications for cancer immunotherapy.

    Science.gov (United States)

    van de Ven, Rieneke; Reurs, Anneke W; Wijnands, Pepijn G J T B; van Wetering, Sandra; Kruisbeek, Ada M; Hooijberg, Erik; Scheffer, George L; Scheper, Rik J; de Gruijl, Tanja D

    2012-02-01

    Appropriate activation of dendritic cells (DC) is essential for successful active vaccination and induction of cell-mediated immunity. The scarcity of precursor cells, as well as long culture methods, have hampered wide-scale application of DC vaccines derived from CD34(+) precursors, despite their suggested superior efficacy over the more commonly applied monocyte-derived DC (MoDC). Here, employing the CD34(+)/CD14(+) AML-derived human DC progenitor cell line MUTZ3, we show that cytostatic anthraquinone-derivatives (i.e., the anthracenedione mitoxantrone and the related anthracyclin doxorubicin) induce rapid differentiation of CD34(+) DC precursors into functional antigen-presenting cells (APC) in a three-day protocol. The drugs were found to act specifically on CD34(+), and not on CD14(+) DC precursors. Importantly, these observations were confirmed for primary CD34(+) and CD14(+) DC precursors from peripheral blood. Mitoxantrone-generated DC were fully differentiated within three days and after an additional 24 h of maturation, were as capable as standard 9-day differentiated and matured DC to migrate toward the lymph node-homing chemokines CCL19 and CCL21, to induce primary allogeneic T cell proliferation, and to prime functional MART1-specific CD8(+) T lymphocytes. Our finding that anthraquinone-derivatives like mitoxantrone support rapid high-efficiency differentiation of DC precursors may have consequences for in vitro production of DC vaccines as well as for novel immunochemotherapy strategies.

  18. Alpha-Synuclein Expression in the Oligodendrocyte Lineage: an In Vitro and In Vivo Study Using Rodent and Human Models

    Directory of Open Access Journals (Sweden)

    Mehdi Djelloul

    2015-08-01

    Full Text Available In this study, we sought evidence for alpha-synuclein (ASYN expression in oligodendrocytes, as a possible endogenous source of ASYN to explain its presence in glial inclusions found in multiple system atrophy (MSA and Parkinson’s disease (PD. We identified ASYN in oligodendrocyte lineage progenitors isolated from the rodent brain, in oligodendrocytes generated from embryonic stem cells, and in induced pluripotent stem cells produced from fibroblasts of a healthy individual and patients diagnosed with MSA or PD, in cultures in vitro. Notably, we observed a significant decrease in ΑSYN during oligodendrocyte maturation. Additionally, we show the presence of transcripts in PDGFRΑ/CD140a+ cells and SOX10+ oligodendrocyte lineage nuclei isolated by FACS from rodent and human healthy and diseased brains, respectively. Our work identifies ASYN in oligodendrocyte lineage cells, and it offers additional in vitro cellular models that should provide significant insights of the functional implication of ASYN during oligodendrocyte development and disease.

  19. Higher vulnerability and stress sensitivity of neuronal precursor cells carrying an alpha-synuclein gene triplication.

    Directory of Open Access Journals (Sweden)

    Adrian Flierl

    Full Text Available Parkinson disease (PD is a multi-factorial neurodegenerative disorder with loss of dopaminergic neurons in the substantia nigra and characteristic intracellular inclusions, called Lewy bodies. Genetic predisposition, such as point mutations and copy number variants of the SNCA gene locus can cause very similar PD-like neurodegeneration. The impact of altered α-synuclein protein expression on integrity and developmental potential of neuronal stem cells is largely unexplored, but may have wide ranging implications for PD manifestation and disease progression. Here, we investigated if induced pluripotent stem cell-derived neuronal precursor cells (NPCs from a patient with Parkinson's disease carrying a genomic triplication of the SNCA gene (SNCA-Tri. Our goal was to determine if these cells these neuronal precursor cells already display pathological changes and impaired cellular function that would likely predispose them when differentiated to neurodegeneration. To achieve this aim, we assessed viability and cellular physiology in human SNCA-Tri NPCs both under normal and environmentally stressed conditions to model in vitro gene-environment interactions which may play a role in the initiation and progression of PD. Human SNCA-Tri NPCs displayed overall normal cellular and mitochondrial morphology, but showed substantial changes in growth, viability, cellular energy metabolism and stress resistance especially when challenged by starvation or toxicant challenge. Knockdown of α-synuclein in the SNCA-Tri NPCs by stably expressed short hairpin RNA (shRNA resulted in reversal of the observed phenotypic changes. These data show for the first time that genetic alterations such as the SNCA gene triplication set the stage for decreased developmental fitness, accelerated aging, and increased neuronal cell loss. The observation of this "stem cell pathology" could have a great impact on both quality and quantity of neuronal networks and could provide a

  20. Tumefactive intracranial presentation of precursor B-cell acute lymphoblastic leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Forester, Craig M. [University of Utah, Salt Lake City, UT (United States); Braunreiter, Chi L. [University of Utah, Division of Pediatric Hematology Oncology, Primary Children' s Medical Center, Salt Lake City, UT (United States); Helen DeVos Children' s Hospital, Department of Pediatric Hematology Oncology, Grand Rapids, MI (United States); Yaish, Hasan; Afify, Zeinab [University of Utah, Division of Pediatric Hematology Oncology, Primary Children' s Medical Center, Salt Lake City, UT (United States); Hedlund, Gary L. [Primary Children' s Medical Center, Department of Pediatric Radiology, Salt Lake City, UT (United States)

    2009-11-15

    In children, leukemia is the most common malignancy, and approximately 75% of leukemias are acute lymphoblastic leukemia (ALL). Central nervous system leukemia is found at diagnosis in fewer than 5% of children with ALL. Leukemic intracranial masses have been described with acute myeloid leukemia, but ALL presenting as a mass lesion is rare. We describe a unique case of an intracranial confirmed precursor B cell (pre-B) ALL mass in a 13-year-old girl that was diagnosed by brain CT, MRI and cerebral angiography, and confirmed by biopsy. This report details pertinent history and distinguishing imaging features of an intracranial ALL tumefaction. (orig.)

  1. Involvement of astrocyte and oligodendrocyte gene sets in migraine.

    Science.gov (United States)

    Eising, Else; de Leeuw, Christiaan; Min, Josine L; Anttila, Verneri; Verheijen, Mark Hg; Terwindt, Gisela M; Dichgans, Martin; Freilinger, Tobias; Kubisch, Christian; Ferrari, Michel D; Smit, August B; de Vries, Boukje; Palotie, Aarno; van den Maagdenberg, Arn Mjm; Posthuma, Danielle

    2016-06-01

    Migraine is a common episodic brain disorder characterized by recurrent attacks of severe unilateral headache and additional neurological symptoms. Two main migraine types can be distinguished based on the presence of aura symptoms that can accompany the headache: migraine with aura and migraine without aura. Multiple genetic and environmental factors confer disease susceptibility. Recent genome-wide association studies (GWAS) indicate that migraine susceptibility genes are involved in various pathways, including neurotransmission, which have already been implicated in genetic studies of monogenic familial hemiplegic migraine, a subtype of migraine with aura. To further explore the genetic background of migraine, we performed a gene set analysis of migraine GWAS data of 4954 clinic-based patients with migraine, as well as 13,390 controls. Curated sets of synaptic genes and sets of genes predominantly expressed in three glial cell types (astrocytes, microglia and oligodendrocytes) were investigated. Our results show that gene sets containing astrocyte- and oligodendrocyte-related genes are associated with migraine, which is especially true for gene sets involved in protein modification and signal transduction. Observed differences between migraine with aura and migraine without aura indicate that both migraine types, at least in part, seem to have a different genetic background. © International Headache Society 2015.

  2. Alternative splicing in the differentiation of human embryonic stem cells into cardiac precursors.

    Directory of Open Access Journals (Sweden)

    Nathan Salomonis

    2009-11-01

    Full Text Available The role of alternative splicing in self-renewal, pluripotency and tissue lineage specification of human embryonic stem cells (hESCs is largely unknown. To better define these regulatory cues, we modified the H9 hESC line to allow selection of pluripotent hESCs by neomycin resistance and cardiac progenitors by puromycin resistance. Exon-level microarray expression data from undifferentiated hESCs and cardiac and neural precursors were used to identify splice isoforms with cardiac-restricted or common cardiac/neural differentiation expression patterns. Splice events for these groups corresponded to the pathways of cytoskeletal remodeling, RNA splicing, muscle specification, and cell cycle checkpoint control as well as genes with serine/threonine kinase and helicase activity. Using a new program named AltAnalyze (http://www.AltAnalyze.org, we identified novel changes in protein domain and microRNA binding site architecture that were predicted to affect protein function and expression. These included an enrichment of splice isoforms that oppose cell-cycle arrest in hESCs and that promote calcium signaling and cardiac development in cardiac precursors. By combining genome-wide predictions of alternative splicing with new functional annotations, our data suggest potential mechanisms that may influence lineage commitment and hESC maintenance at the level of specific splice isoforms and microRNA regulation.

  3. Leukemia inhibitory factor favours neurogenic differentiation of long-term propagated human midbrain precursor cells

    DEFF Research Database (Denmark)

    Andersen, Rikke K; Widmer, Hans R; Zimmer, Jens;

    2009-01-01

    , human embryonic (5 weeks post-conception) ventral mesencephalic (VM) precursor cells were propagated as neural tissue-spheres (NTS) in epidermal growth factor (EGF; 20 ng/ml) and fibroblast growth factor 2 (FGF2; 20 ng/ml). After more than 325 days, the NTS were transferred to media containing either...... EGF+FGF2, EGF+FGF2+heparin or leukemia inhibitory factor (LIF; 10 ng/ml)+FGF2+heparin. Cultures were subsequently propagated for more than 180 days with NTS analyzed at various time-points. Our data show for the first time that human VM neural precursor cells can be long-term propagated as NTS...... in the presence of EGF and FGF2. A positive effect of heparin was found only after 150 days of treatment. After switching into different media, only NTS exposed to LIF contained numerous cells positive for markers of newly formed neurons. Besides of demonstrating the ability of human VM NTS to be long...

  4. Envisaging an allogenic Corneal endothelial precursor/Stem Cell Bank (CESBANK

    Directory of Open Access Journals (Sweden)

    Parikumar P

    2008-01-01

    Full Text Available Bullous Keratopathy (BK affects thousands of people in India every year. Though in early stages it is manageable medically, advanced disease warrants either total corneal transplantation or partial thickness transplantation for which a donor-cadaver cornea is necessary. Amano et al have reported the successful treatment of BK in animal models using in-vitro expanded human corneal endothelial precursors; though the rabbits had to be kept facing eye down to allow gravity assisted settling of the cells to the summit of the cornea where the damage had been created. For successful treatment using the above method, a human being has to lie prone with eyes immobilized for 24-36 Hrs. This is extremely discomforting and hence not practical. Corneal endothelium removed from the button and transported at varying temperature conditions for 48Hrs was successfully cultured in NCRM and this was reported earlier. We are working on a suitable scaffold to retain the cells in situ until their attachment to the damaged portion of the corneal endothelium enabling it to heal without the patient having to lie prone. With such capability, we envisage to make a corneal endothelial precursor/stem cell (CES bank named as CESBANK to make in-vitro expanded CES available for patients with corneal diseases, most commonly Bullous Keratopathy (BK.

  5. Stochastic specification of primordial germ cells from mesoderm precursors in axolotl embryos.

    Science.gov (United States)

    Chatfield, Jodie; O'Reilly, Marie-Anne; Bachvarova, Rosemary F; Ferjentsik, Zoltan; Redwood, Catherine; Walmsley, Maggie; Patient, Roger; Loose, Mathew; Johnson, Andrew D

    2014-06-01

    A common feature of development in most vertebrate models is the early segregation of the germ line from the soma. For example, in Xenopus and zebrafish embryos primordial germ cells (PGCs) are specified by germ plasm that is inherited from the egg; in mice, Blimp1 expression in the epiblast mediates the commitment of cells to the germ line. How these disparate mechanisms of PGC specification evolved is unknown. Here, in order to identify the ancestral mechanism of PGC specification in vertebrates, we studied PGC specification in embryos from the axolotl (Mexican salamander), a model for the tetrapod ancestor. In the axolotl, PGCs develop within mesoderm, and classic studies have reported their induction from primitive ectoderm (animal cap). We used an axolotl animal cap system to demonstrate that signalling through FGF and BMP4 induces PGCs. The role of FGF was then confirmed in vivo. We also showed PGC induction by Brachyury, in the presence of BMP4. These conditions induced pluripotent mesodermal precursors that give rise to a variety of somatic cell types, in addition to PGCs. Irreversible restriction of the germ line did not occur until the mid-tailbud stage, days after the somatic germ layers are established. Before this, germline potential was maintained by MAP kinase signalling. We propose that this stochastic mechanism of PGC specification, from mesodermal precursors, is conserved in vertebrates.

  6. The Hippo pathway regulates homeostatic growth of stem cell niche precursors in the Drosophila ovary.

    Science.gov (United States)

    Sarikaya, Didem P; Extavour, Cassandra G

    2015-02-01

    The Hippo pathway regulates organ size, stem cell proliferation and tumorigenesis in adult organs. Whether the Hippo pathway influences establishment of stem cell niche size to accommodate changes in organ size, however, has received little attention. Here, we ask whether Hippo signaling influences the number of stem cell niches that are established during development of the Drosophila larval ovary, and whether it interacts with the same or different effector signaling pathways in different cell types. We demonstrate that canonical Hippo signaling regulates autonomous proliferation of the soma, while a novel hippo-independent activity of Yorkie regulates autonomous proliferation of the germ line. Moreover, we demonstrate that Hippo signaling mediates non-autonomous proliferation signals between germ cells and somatic cells, and contributes to maintaining the correct proportion of these niche precursors. Finally, we show that the Hippo pathway interacts with different growth pathways in distinct somatic cell types, and interacts with EGFR and JAK/STAT pathways to regulate non-autonomous proliferation of germ cells. We thus provide evidence for novel roles of the Hippo pathway in establishing the precise balance of soma and germ line, the appropriate number of stem cell niches, and ultimately regulating adult female reproductive capacity.

  7. Adult subependymal neural precursors, but not differentiated cells, undergo rapid cathodal migration in the presence of direct current electric fields.

    Directory of Open Access Journals (Sweden)

    Robart Babona-Pilipos

    Full Text Available BACKGROUND: The existence of neural stem and progenitor cells (together termed neural precursor cells in the adult mammalian brain has sparked great interest in utilizing these cells for regenerative medicine strategies. Endogenous neural precursors within the adult forebrain subependyma can be activated following injury, resulting in their proliferation and migration toward lesion sites where they differentiate into neural cells. The administration of growth factors and immunomodulatory agents following injury augments this activation and has been shown to result in behavioural functional recovery following stroke. METHODS AND FINDINGS: With the goal of enhancing neural precursor migration to facilitate the repair process we report that externally applied direct current electric fields induce rapid and directed cathodal migration of pure populations of undifferentiated adult subependyma-derived neural precursors. Using time-lapse imaging microscopy in vitro we performed an extensive single-cell kinematic analysis demonstrating that this galvanotactic phenomenon is a feature of undifferentiated precursors, and not differentiated phenotypes. Moreover, we have shown that the migratory response of the neural precursors is a direct effect of the electric field and not due to chemotactic gradients. We also identified that epidermal growth factor receptor (EGFR signaling plays a role in the galvanotactic response as blocking EGFR significantly attenuates the migratory behaviour. CONCLUSIONS: These findings suggest direct current electric fields may be implemented in endogenous repair paradigms to promote migration and tissue repair following neurotrauma.

  8. Effects of insulin-like growth factor-1 on B-cell precursor acute lymphoblastic leukemia.

    Science.gov (United States)

    Yamada, Hiroyuki; Iijima, Kazutoshi; Tomita, Osamu; Taguchi, Tomoko; Miharu, Masashi; Kobayashi, Kenichiro; Okita, Hajime; Saito, Masahiro; Shimizu, Toshiaki; Kiyokawa, Nobutaka

    2013-01-01

    Insulin-like growth factor-1 (IGF-1) is known to be a major growth factor with effects on various cell types, including hematopoietic cells, as well as neoplasms, and is regulated by IGF-binding proteins (IGFBPs). In this study, we investigated the effects of IGF-1 on B-cell precursor acute lymphoblastic leukemia (BCP-ALL) cells. When the expression of IGF-1R in clinical samples of BCP-ALL was examined, five of thirty-two cases showed IGF-1R expression, whereas IGF-1R was expressed in most BCP-ALL cell lines. We observed that IGF-1 enhanced the proliferation of BCP-ALL cell lines that can be partially inhibited by IGFBP-1, -3, and -4, but not other IGFBPs. IGF-1 also partially inhibited dexamethasone-induced apoptosis, but not apoptosis mediated by VP-16 and irradiation. Interestingly, the proliferative effect of IGF-1 was partially blocked by inhibitors of MAPK and AKT, whereas the inhibition of dexamethasone-induced apoptosis was completely blocked by both inhibitors. Our data indicate that IGF-1 is involved in cell proliferation and apoptosis regulation in BCP-ALL cells. Since some BCP-ALL cases express IGF-1R, it appears to be a plausible target for prognostic evaluation and may represent a new therapeutic strategy.

  9. Pío del Río Hortega and the discovery of the oligodendrocytes

    Directory of Open Access Journals (Sweden)

    Fernando ePérez-Cerdá

    2015-07-01

    Full Text Available Pío del Río Hortega (1882-1945 discovered microglia and oligodendrocytes and was after Ramón y Cajal, the most prominent figure of the Spanish school of neurology. He began his scientific career with Nicolás Achúcarro with whom he learned the use of metallic impregnation techniques suitable to study non neuronal cells. Later on, he joined Cajal´s laboratory, and afterwards he created his own group where he continued developing other innovative modifications of the silver staining methods that revolutionised the study of glial cells a century ago. He was at that time also interested in neuropathology and became a leading authority in Central Nervous System (CNS tumours. In parallel to this clinical activity, del Río Hortega rendered the first systematic description of the great polymorphism present in a subtype of macroglial cells that he named himself as oligodendroglia and later oligodendrocytes. He established their ectodermic origin and suggested that they build the myelin sheath of CNS axons, just as Schwann cells do in the periphery. Notably, he also suggested the trophic role of oligodendrocytes for neuronal functionality, an idea that it has been substantiated in the last few years. Del Río Hortega became internationally recognized and established an important neurohistological school with outstanding pupils from Spain and abroad, which nearly disappeared after his exile due to the Spanish civil war. Yet, the difficulty of metal impregnation methods and their variability in results, delayed for some decades the confirmation of his great insights into oligodendrocyte biology until the development of electron microscopy and immunohistochemistry. This review aims at summarizing the pioneer and essential contributions of del Río Hortega to the current knowledge of oligodendrocyte structure and function, and to provide a hint of the scientific personality of this extraordinary and insufficiently recognized man.

  10. Noscapine protects OLN-93 oligodendrocytes from ischemia-reperfusion damage: Calcium and nitric oxide involvement.

    Science.gov (United States)

    Nadjafi, S; Ebrahimi, S-A; Rahbar-Roshandel, N

    2015-12-01

    This study was carried out to evaluate the effects of noscapine, a benzylisoquinoline alkaloid from opium poppy, on oligodendrocyte during ischemia/reperfusion-induced excitotoxic injury. Changes in intracellular calcium levels due to chemical ischemia and nitric oxide (NO) production during ischemia/reperfusion were evaluated as the hallmarks of ischemia-derived excitotoxic event. OLN-93 cell line (a permanent immature rat oligodendrocyte) was used as a model of oligodendrocyte. 30- or 60-minute-oxygen-glucose deprivation/24 hours reperfusion were used to induce excitotoxicity. MTT (3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) assay was used to evaluate cell viability. Ratiometric fluorescence microscopy using Ca(2+)-sensitive indicator Fura-2/AM was utilized to assess intracellular calcium levels. NO production was evaluated by Griess method. Noscapine (4 μM) significantly attenuated intracellular Ca(2+) elevation (P noscapine significantly decreased NO production during a 30-minute oxygen-glucose deprivation/reperfusion (P noscapine (4 μM) on intracellular Ca(2+) was greater than ionotropic glutamate receptors antagonists. Noscapine is protective against ischemia/reperfusion-induced excitotoxic injury in OLN-93 oligodendrocyte. This protective effect seems to be related to attenuation of intracellular Ca(2+) overload and NO production.

  11. Flt3+ macrophage precursors commit sequentially to osteoclasts, dendritic cells and microglia

    Directory of Open Access Journals (Sweden)

    Hanau Daniel

    2002-10-01

    Full Text Available Abstract Background Macrophages, osteoclasts, dendritic cells, and microglia are highly specialized cells that belong to the mononuclear phagocyte system. Functional and phenotypic heterogeneity within the mononuclear phagocyte system may reveal differentiation plasticity of a common progenitor, but developmental pathways leading to such diversity are still unclear. Results Mouse bone marrow cells were expanded in vitro in the presence of Flt3-ligand (FL, yielding high numbers of non-adherent cells exhibiting immature monocyte characteristics. Cells expanded for 6 days, 8 days, or 11 days (day 6-FL, day 8-FL, and day 11-FL cells, respectively exhibited constitutive potential towards macrophage differentiation. In contrast, they showed time-dependent potential towards osteoclast, dendritic, and microglia differentiation that was detected in day 6-, day 8-, and day 11-FL cells, in response to M-CSF and receptor activator of NFκB ligand (RANKL, granulocyte-macrophage colony stimulating-factor (GM-CSF and tumor necrosis factor-α (TNFα, and glial cell-conditioned medium (GCCM, respectively. Analysis of cell proliferation using the vital dye CFSE revealed homogenous growth in FL-stimulated cultures of bone marrow cells, demonstrating that changes in differential potential did not result from sequential outgrowth of specific precursors. Conclusions We propose that macrophages, osteoclasts, dendritic cells, and microglia may arise from expansion of common progenitors undergoing sequential differentiation commitment. This study also emphasizes differentiation plasticity within the mononuclear phagocyte system. Furthermore, selective massive cell production, as shown here, would greatly facilitate investigation of the clinical potential of dendritic cells and microglia.

  12. Amyloid precursor protein regulates migration and metalloproteinase gene expression in prostate cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Miyazaki, Toshiaki; Ikeda, Kazuhiro; Horie-Inoue, Kuniko [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama 350-1241 (Japan); Inoue, Satoshi, E-mail: INOUE-GER@h.u-tokyo.ac.jp [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama 350-1241 (Japan); Department of Geriatric Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8655 (Japan); Department of Anti-Aging Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8655 (Japan)

    2014-09-26

    Highlights: • APP knockdown reduced proliferation and migration of prostate cancer cells. • APP knockdown reduced expression of metalloproteinase and EMT-related genes. • APP overexpression promoted LNCaP cell migration. • APP overexpression increased expression of metalloproteinase and EMT-related genes. - Abstract: Amyloid precursor protein (APP) is a type I transmembrane protein, and one of its processed forms, β-amyloid, is considered to play a central role in the development of Alzheimer’s disease. We previously showed that APP is a primary androgen-responsive gene in prostate cancer and that its increased expression is correlated with poor prognosis for patients with prostate cancer. APP has also been implicated in several human malignancies. Nevertheless, the mechanism underlying the pro-proliferative effects of APP on cancers is still not well-understood. In the present study, we explored a pathophysiological role for APP in prostate cancer cells using siRNA targeting APP (siAPP). The proliferation and migration of LNCaP and DU145 prostate cancer cells were significantly suppressed by siAPP. Differentially expressed genes in siAPP-treated cells compared to control siRNA-treated cells were identified by microarray analysis. Notably, several metalloproteinase genes, such as ADAM10 and ADAM17, and epithelial–mesenchymal transition (EMT)-related genes, such as VIM, and SNAI2, were downregulated in siAPP-treated cells as compared to control cells. The expression of these genes was upregulated in LNCaP cells stably expressing APP when compared with control cells. APP-overexpressing LNCaP cells exhibited enhanced migration in comparison to control cells. These results suggest that APP may contribute to the proliferation and migration of prostate cancer cells by modulating the expression of metalloproteinase and EMT-related genes.

  13. In Vitro Epigenetic Reprogramming of Human Cardiac Mesenchymal Stromal Cells into Functionally Competent Cardiovascular Precursors

    Science.gov (United States)

    Vecellio, Matteo; Meraviglia, Viviana; Nanni, Simona; Barbuti, Andrea; Scavone, Angela; DiFrancesco, Dario; Farsetti, Antonella; Pompilio, Giulio; Colombo, Gualtiero I.; Capogrossi, Maurizio C.

    2012-01-01

    Adult human cardiac mesenchymal-like stromal cells (CStC) represent a relatively accessible cell type useful for therapy. In this light, their conversion into cardiovascular precursors represents a potential successful strategy for cardiac repair. The aim of the present work was to reprogram CStC into functionally competent cardiovascular precursors using epigenetically active small molecules. CStC were exposed to low serum (5% FBS) in the presence of 5 µM all-trans Retinoic Acid (ATRA), 5 µM Phenyl Butyrate (PB), and 200 µM diethylenetriamine/nitric oxide (DETA/NO), to create a novel epigenetically active cocktail (EpiC). Upon treatment the expression of markers typical of cardiac resident stem cells such as c-Kit and MDR-1 were up-regulated, together with the expression of a number of cardiovascular-associated genes including KDR, GATA6, Nkx2.5, GATA4, HCN4, NaV1.5, and α-MHC. In addition, profiling analysis revealed that a significant number of microRNA involved in cardiomyocyte biology and cell differentiation/proliferation, including miR 133a, 210 and 34a, were up-regulated. Remarkably, almost 45% of EpiC-treated cells exhibited a TTX-sensitive sodium current and, to a lower extent in a few cells, also the pacemaker If current. Mechanistically, the exposure to EpiC treatment introduced global histone modifications, characterized by increased levels of H3K4Me3 and H4K16Ac, as well as reduced H4K20Me3 and H3s10P, a pattern compatible with reduced proliferation and chromatin relaxation. Consistently, ChIP experiments performed with H3K4me3 or H3s10P histone modifications revealed the presence of a specific EpiC-dependent pattern in c-Kit, MDR-1, and Nkx2.5 promoter regions, possibly contributing to their modified expression. Taken together, these data indicate that CStC may be epigenetically reprogrammed to acquire molecular and biological properties associated with competent cardiovascular precursors. PMID:23284745

  14. In vitro epigenetic reprogramming of human cardiac mesenchymal stromal cells into functionally competent cardiovascular precursors.

    Directory of Open Access Journals (Sweden)

    Matteo Vecellio

    Full Text Available Adult human cardiac mesenchymal-like stromal cells (CStC represent a relatively accessible cell type useful for therapy. In this light, their conversion into cardiovascular precursors represents a potential successful strategy for cardiac repair. The aim of the present work was to reprogram CStC into functionally competent cardiovascular precursors using epigenetically active small molecules. CStC were exposed to low serum (5% FBS in the presence of 5 µM all-trans Retinoic Acid (ATRA, 5 µM Phenyl Butyrate (PB, and 200 µM diethylenetriamine/nitric oxide (DETA/NO, to create a novel epigenetically active cocktail (EpiC. Upon treatment the expression of markers typical of cardiac resident stem cells such as c-Kit and MDR-1 were up-regulated, together with the expression of a number of cardiovascular-associated genes including KDR, GATA6, Nkx2.5, GATA4, HCN4, NaV1.5, and α-MHC. In addition, profiling analysis revealed that a significant number of microRNA involved in cardiomyocyte biology and cell differentiation/proliferation, including miR 133a, 210 and 34a, were up-regulated. Remarkably, almost 45% of EpiC-treated cells exhibited a TTX-sensitive sodium current and, to a lower extent in a few cells, also the pacemaker I(f current. Mechanistically, the exposure to EpiC treatment introduced global histone modifications, characterized by increased levels of H3K4Me3 and H4K16Ac, as well as reduced H4K20Me3 and H3s10P, a pattern compatible with reduced proliferation and chromatin relaxation. Consistently, ChIP experiments performed with H3K4me3 or H3s10P histone modifications revealed the presence of a specific EpiC-dependent pattern in c-Kit, MDR-1, and Nkx2.5 promoter regions, possibly contributing to their modified expression. Taken together, these data indicate that CStC may be epigenetically reprogrammed to acquire molecular and biological properties associated with competent cardiovascular precursors.

  15. Synthesis of albumin via a precursor protein in cell suspensions from rat liver.

    Science.gov (United States)

    Edwards, K; Schreiber, G; Dryburgh, H; Urban, J; Inglis, A S

    1976-03-16

    The mechanism of the biosynthesis of albumin was studied in cell suspensions from rat liver. The cells were prepared by continuous perfusion of the liver in situ with 0.05% collagenase and 0.10% hyaluronidase and incubated under conditions optimized for the incorporation of amino acids into protein. Seven minutes after starting the incubation L-[1-14C]leucine was added, followed after 25 min by a 15 or 30-min chase with an 830-fold excess of non-radioactive L-leucine. Total protein, an albumin-like protein, and albumin were isolated from samples withdrawn immediately of total protein was found to remain constant after addition of the non-radioactive L-leucine, whereas that of the albumin-like protein decreased and that of albumin increased with incubation time. The increase in albumin radioactivity accounted for the decrease in radioactivity of the albumin-like protein, suggesting that the latter is a precursor of albumin. The precursor protein differed from albumin by an oligopeptide extension at the N-terminal end.

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

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Liang [East Hospital, Tongji University School of Medicine, Shanghai (China); Dong, Chuanming [East Hospital, Tongji University School of Medicine, Shanghai (China); Department of Anatomy and Neurobiology, The Jiangsu Key Laboratory of Neuroregeneration, Nantong University, Nantong (China); Sun, Chenxi; Ma, Rongjie; Yang, Danjing [East Hospital, Tongji University School of Medicine, Shanghai (China); Zhu, Hongwen, E-mail: hongwen_zhu@hotmail.com [Tianjin Hospital, Tianjin Academy of Integrative Medicine, Tianjin (China); Xu, Jun, E-mail: xunymc2000@yahoo.com [East Hospital, Tongji University School of Medicine, Shanghai (China)

    2015-08-21

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

  17. Effect of precursor nature on the performance of palladium-cobalt electrocatalysts for direct methanol fuel cells

    Science.gov (United States)

    Serov, Alexey; Nedoseykina, Tatyana; Shvachko, Oleg; Kwak, Chan

    The performance of platinum-free palladium-cobalt catalysts in oxygen reduction was investigated for a direct methanol fuel cell. The dependence of catalytic activity on precursor nature was determined for two classes of precursors; namely, palladium chloride and palladium nitrate. The nitrate precursor exhibits much higher catalytic performance than the chloride precursor. X-ray absorption fine structure (XAFS) spectra indicate that the structure of palladium catalyst prepared from nitrate is much closer to Pd 3Co structure that can explain high catalytic activity. The MEA prepared from the nitrate catalyst achieved the peak power density of 125 mW cm -2, which is much higher than 19 mW cm -2 measured on the cell prepared from the chloride catalyst.

  18. CuIn(S,Se){sub 2}thin film solar cells from nanocrystal inks: Effect of nanocrystal precursors

    Energy Technology Data Exchange (ETDEWEB)

    Ford, Grayson M.; Guo Qijie [School of Chemical Engineering and The Energy Center, Purdue University, 480 Stadium Mall Dr., West Lafayette, IN 47907 (United States); Agrawal, Rakesh, E-mail: agrawalr@purdue.edu [School of Chemical Engineering and The Energy Center, Purdue University, 480 Stadium Mall Dr., West Lafayette, IN 47907 (United States); Hillhouse, Hugh W., E-mail: h2@uw.edu [School of Chemical Engineering and The Energy Center, Purdue University, 480 Stadium Mall Dr., West Lafayette, IN 47907 (United States); Department of Chemical Engineering, University of Washington, Seattle WA 98105 (United States)

    2011-10-31

    CuIn(S,Se){sub 2} thin film solar cells are fabricated by selenizing CuInS{sub 2} nanocrystals synthesized using a variety of copper and indium precursors. Specifically, copper and indium acetates, acetylacetonates, iodides, chlorides and nitrates are investigated to determine the effect of precursors on electronic properties and device performance. Nanocrystal synthesis with each of these precursors can be optimized to yield similar nanocrystal composition, size and structure. In addition, dense chalcopyrite CuIn(S,Se){sub 2} thin films with micron sized grains at the surface are formed upon selenization regardless of precursor type. Surprisingly, solar cells fabricated from each nanocrystal ink have roughly the same carrier concentrations of 10{sup 16} to 10{sup 17} cm{sup -3} in the absorber layer and achieve active area efficiencies of approximately 5%.

  19. Biochemical precursor effects on the fatty acid production in cell suspension cultures of Theobroma cacao L.

    Science.gov (United States)

    Parra, O; Gallego, A M; Urrea, A; Rojas, L F; Correa, C; Atehortúa, L

    2017-02-01

    Cocoa butter (CB) is composed of 96% palmitic, stearic, oleic, linoleic and linolenic fatty acids that are responsible for the hardness, texture and fusion properties of chocolate. Through in vitro plant cell culture it is possible to modify CB lipid profiles and to study the fatty acid biosynthesis pathway on a subcellular level, evaluating fundamental aspects to enhance in vitro fatty acid production in a specific and controlled way. In this research, culture media was supplemented with acetate, biotin, pyruvate, bicarbonate and glycerol at three different concentrations and the effects on the biomass production (g/L), cell viability, and fatty acids profile and production was evaluated in in vitro cell suspensions culture. It was found that biotin stimulated fatty acid synthesis without altering cell viability and cell growth. It was also evident a change in the lipid profile of cell suspensions, increasing middle and long chain fatty acids proportion, which are unusual to those reported in seeds; thus implying that it is possible to modify lipid profiles according to the treatment used. According to the results of sucrose gradients and enzyme assays performed, it is proposed that cacao cells probably use the pentose phosphate pathway, mitochondria being the key organelle in the carbon flux for the synthesis of reductant power and fatty acid precursors. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  20. Cannabidiol Activates Neuronal Precursor Genes in Human Gingival Mesenchymal Stromal Cells.

    Science.gov (United States)

    Soundara Rajan, Thangavelu; Giacoppo, Sabrina; Scionti, Domenico; Diomede, Francesca; Grassi, Gianpaolo; Pollastro, Federica; Piattelli, Adriano; Bramanti, Placido; Mazzon, Emanuela; Trubiani, Oriana

    2016-12-05

    In the last years, mesenchymal stromal cells (MSCs) from oral tissues have received considerable interest in regenerative medicine since they can be obtained with minimal invasive procedure and exhibit immunomodulatory properties. This study was aimed to investigate whether in vitro pre-treatment of MSCs obtained from human gingiva (hGMSCs) with Cannabidiol (CBD), a cannabinoid component produced by the plant Cannabis sativa, may promote human gingiva derived MSCs to differentiate toward neuronal precursor cells. Specifically, we have treated the hGMSCs with CBD (5 µM) for 24 h in order to evaluate the expression of genes involved in cannabidiol signaling, cell proliferation, self-renewal and multipotency, and neural progenitor cells differentiation. Next generation sequencing (NGS) demonstrated that CBD activates genes associated with G protein coupled receptor signaling in hGMSCs. Genes involved in DNA replication, cell cycle, proliferation, and apoptosis were regulated. Moreover, genes associated with the biological process of neuronal progenitor cells (NCPs) proliferation, neuron differentiation, neurogenesis, and nervous system development were significantly modulated. From our results, we hypothesize that human gingiva-derived MSCs conditioned with CBD could represent a valid method for improving the hGMSCs phenotype and thus might be a potential therapeutic tool in the treatment of neurodegenerative diseases. J. Cell. Biochem. 9999: 1-16, 2016. © 2016 Wiley Periodicals, Inc.

  1. Transplantation of primary cultured embryonic mesencephalic neural precursor cells for treating Parkinsonian rats

    Institute of Scientific and Technical Information of China (English)

    Li Fei; Chengchuan Jiang; Linyin Feng; Yaodong Ji; Zhongliang Ding

    2006-01-01

    BACKGROUND: Choosing proper donor cells is one of keys in experimental and clinical studies on cell replacement therapy (CRT) for treating Parkinson disease (PD). Embryonic mesencephalic precursor cells (MPCs) can stably differentiate into dopaminergic neuron after in vitro proliferated culture. As compared with embryonic stem cell and neural stem cell strains, cell composition of embryonic MPCs after primary culture is also the most close to that of embryonic mesencephalic ventral cell suspension without proliferated culture. Successful experience accumulated in the latter suggests that primary cultured embryonic MPCs might be the most potential donor cells in clinical application with CRT for treating PD so far.OBJECTIVE: To investigate the feasibility of primary cultured embryonic precursor cells cultured primarily as donor cells in CRT for treating PD in rats.DESIGN: A randomized and controlled trial taking SD rats as experimental animals.SETTING: Department of Neurosurgery, Huashan Hospital Affiliated to Fudan University.MATERIALS: This experiment was carried out at the Institute of Neuroscience, Shanghai Institute for Biological Science, Chinese Academy of Sciences from July 2003 to June 2004. Totally 26 female SD rats,with body mass of 200 to 220 g, were provided by Shanghai Experimental Animal Center of Chinese Academy of Sciences.METHODS: Stereotaxic injection of 6-hydroxydopamine into the medial forebrain bundle were perfored to develop PD model rat. Among 26 SD rats, 20 rats achieved a more than 5 turns/min in apomorphine induced rotation test, reaching the standard of PD model rats. Immunohistochemical detection was performed on 1out of 20 model rats after execution, and the other 19 rats were randomly divided into control group (n=5),sham transplantation group (n=5)and cell grafted group (n=9). Primary cultured E12 MPC cell suspension (1.2×1011 L-1)were used as donor cells. 4 μL primary cultured E12 MPC cell suspension prepared freshly was injected

  2. Variability of doublecortin-associated dendrite maturation in adult hippocampal neurogenesis is independent of the regulation of precursor cell proliferation

    Directory of Open Access Journals (Sweden)

    Jessberger Sebastian

    2006-11-01

    Full Text Available Abstract Background In the course of adult hippocampal neurogenesis most regulation takes place during the phase of doublecortin (DCX expression, either as pro-proliferative effect on precursor cells or as survival-promoting effect on postmitotic cells. We here obtained quantitative data about the proliferative population and the dynamics of postmitotic dendrite development during the period of DCX expression. The question was, whether any indication could be obtained that the initiation of dendrite development is timely bound to the exit from the cell cycle. Alternatively, the temporal course of morphological maturation might be subject to additional regulatory events. Results We found that (1 20% of the DCX population were precursor cells in cell cycle, whereas more than 70% were postmitotic, (2 the time span until newborn cells had reached the most mature stage associated with DCX expression varied between 3 days and several weeks, (3 positive or negative regulation of precursor cell proliferation did not alter the pattern and dynamics of dendrite development. Dendrite maturation was largely independent of close contacts to astrocytes. Conclusion These data imply that dendrite maturation of immature neurons is initiated at varying times after cell cycle exit, is variable in duration, and is controlled independently of the regulation of precursor cell proliferation. We conclude that in addition to the major regulatory events in cell proliferation and selective survival, additional micro-regulatory events influence the course of adult hippocampal neurogenesis.

  3. The Snail transcription factor regulates the numbers of neural precursor cells and newborn neurons throughout mammalian life.

    Directory of Open Access Journals (Sweden)

    Mark A Zander

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

  4. Mobilization of endothelial precursor cells: systemic vascular response to musculoskeletal trauma.

    LENUS (Irish Health Repository)

    Laing, A J

    2012-02-03

    Postnatal vasculogenesis, the process by which vascular committed bone marrow stem cells or endothelial precursor cells (EPC) migrate, differentiate, and incorporate into the nacent endothelium contributing to physiological and pathological neovascularization, has stimulated much interest. Its contribution to tumor nonvascularization, wound healing, and revascularization associated with skeletal and cardiac muscles ischaemia is established. We evaluated the mobilization of EPCs in response to musculoskeletal trauma. Blood from patients (n = 15) following AO type 42a1 closed diaphyseal tibial fractures was analyzed for CD34 and AC133 cell surface marker expression. Immunomagnetically enriched CD34+ mononuclear cell (MNC(CD34+)) populations were cultured and examined for phenotypic and functional vascular endothelial differentiation. Circulating MNC(CD34+) levels increased sevenfold by day 3 postinjury. Circulating MNC(AC133+) increased 2.5-fold. Enriched MNC(CD34+) populations from day 3 samples in culture exhibited cell cluster formation with sprouting spindles. These cells bound UEA-1 and incorporated fluorescent DiI-Ac-LDL intracellularily. Our findings suggest a systemic provascular response is initiated in response to musculoskeletal trauma. Its therapeutic manipulation may have implications for the potential enhancement of fracture healing.

  5. Amyloid precursor proteins, neural differentiation of pluripotent stem cells and its relevance to Alzheimer's disease.

    Science.gov (United States)

    Khandekar, Neeta; Lie, Khun Hong; Sachdev, Perminder S; Sidhu, Kuldip S

    2012-05-01

    Alzheimer's disease (AD) is a leading cause of age-related dementia that is characterized by an extensive loss of neurons and synaptic transmission. The pathological hallmarks of AD are neurofibrillary tangles and deposition of β-amyloid (Aβ) plaques. Previous research has investigated how Aβ fragments disrupt synaptic mechanisms in the vulnerable regions of the brain. There is a tremendous potential for stem cell technology to extend upon this research, not only in terms of developing therapeutic applications, but also in modeling AD. Indeed, the advent of induced pluripotent stem cell technology has opened up exciting new avenues for generating patient and disease-specific cell lines from somatic cells that may be used to model AD. Amyloid precursor protein (APP) is a key protein in neuronal development and this article reviews the role of APP in AD. Stem cell technology offers the opportunity to make use of APP in the directed differentiation of induced pluripotent stem cells into functional neurons, a process that may help generate a model of AD and thereby facilitate an understanding of the mechanisms underlying this disease.

  6. An Atlas of Network Topologies Reveals Design Principles for Caenorhabditis elegans Vulval Precursor Cell Fate Patterning.

    Science.gov (United States)

    Ping, Xianfeng; Tang, Chao

    2015-01-01

    The vulval precursor cell (VPC) fate patterning in Caenorhabditis elegans is a classic model experimental system for cell fate determination and patterning in development. Despite its apparent simplicity (six neighboring cells arranged in one dimension) and many experimental and computational efforts, the patterning strategy and mechanism remain controversial due to incomplete knowledge of the complex biology. Here, we carry out a comprehensive computational analysis and obtain a reservoir of all possible network topologies that are capable of VPC fate patterning under the simulation of various biological environments and regulatory rules. We identify three patterning strategies: sequential induction, morphogen gradient and lateral antagonism, depending on the features of the signal secreted from the anchor cell. The strategy of lateral antagonism, which has not been reported in previous studies of VPC patterning, employs a mutual inhibition of the 2° cell fate in neighboring cells. Robust topologies are built upon minimal topologies with basic patterning strategies and have more flexible and redundant implementations of modular functions. By simulated mutation, we find that all three strategies can reproduce experimental error patterns of mutants. We show that the topology derived by mapping currently known biochemical pathways to our model matches one of our identified functional topologies. Furthermore, our robustness analysis predicts a possible missing link related to the lateral antagonism strategy. Overall, we provide a theoretical atlas of all possible functional networks in varying environments, which may guide novel discoveries of the biological interactions in vulval development of Caenorhabditis elegans and related species.

  7. Cell surface phenotype of cytolytic T lymphocyte precursors in aged nude mice.

    Science.gov (United States)

    Maryanski, J L; MacDonald, H R; Sordat, B; Cerottini, J C

    1981-12-01

    The cell surface phenotype of cytolytic T lymphocyte precursors (CTL-P) in congenitally athymic C57BL/6 nu/nu mice has been investigated. CTL-P were detected and quantitated in a limited dilution mixed leukocyte microculture assay system supplemented with interleukin 2. Minimal estimates of the frequency of CTL-P among nylon wool passed (NWP) nude spleen cells were obtained following elimination of Thy-1-bearing or Lyt-2-bearing cells with monoclonal antibodies plus complement. Alternatively, NWP spleen cells bearing Thy-1 or Lyt-2 were positively selected on a cell sorter and assayed for CTL-P frequency. Both positive and negative selection techniques demonstrated that essentially all (greater than 98%) CTL-P in NWP nude spleen expressed Thy-1 and that the majority (80-90%) expressed Lyt-2. In control NWP spleen cells from normal C57BL/6 mice, greater than 98% of CTL-P were positive for both Thy-1 and Lyt-2. These data demonstrate that most functional alloreactive CTL-P developing in the apparent absence of thymic influence already express both Thy-1 and Lyt-2 prior to exposure to antigen.

  8. Oligodendrocyte gap junction loss and disconnection from reactive astrocytes in multiple sclerosis gray matter.

    Science.gov (United States)

    Markoullis, Kyriaki; Sargiannidou, Irene; Schiza, Natasa; Roncaroli, Federico; Reynolds, Richard; Kleopa, Kleopas A

    2014-09-01

    Gap junctions are essential for glial cell function and have been increasingly implicated in multiple sclerosis (MS). Because increasing cortical abnormalities correlate with disease progression and cognitive dysfunction, we examined the expression of oligodendrocytic connexin32 (Cx32) and Cx47 and their astrocytic partners Cx30 and Cx43 in cortical lesions and normal-appearing gray matter (NAGM) in MS patients. Postmortem brain tissue samples from 9 MS cases were compared with 10 controls using real-time polymerase chain reaction, immunoblot, and immunohistochemical analyses. Connexin32 and Cx47 gap junction formation in oligodendrocytes was reduced within lesions, whereas Cx32 loss also extended to NAGM. In contrast, astrocytic Cx30 expression was increased within cortical lesions, whereas Cx43 was elevated in both lesions and NAGM. Diffuse microglial activation and marked astrogliotic changes accompanied these connexin abnormalities. Increased expression of Cx43 correlated with inflammatory load (r = 0.828, p = 0.042), whereas Cx32 expression correlated with longer disease duration and, therefore, milder course (r = 0.825, p = 0.043). Thus, there is a loss of intramyelin and intercellular oligodendrocyte gap junctions in MS gray matter lesions and NAGM, whereas interastrocytic gap junctions are increased, reflecting astrogliosis. These changes correlate with inflammation and disease duration and suggest that disconnection of oligodendrocytes from reactive astrocytes may play a role in failed remyelination and disease progression.

  9. Notch signaling differentially regulates the cell fate of early endocrine precursor cells and their maturing descendants in the mouse pancreas and intestine.

    Science.gov (United States)

    Li, Hui Joyce; Kapoor, Archana; Giel-Moloney, Maryann; Rindi, Guido; Leiter, Andrew B

    2012-11-15

    Notch signaling inhibits differentiation of endocrine cells in the pancreas and intestine. In a number of cases, the observed inhibition occurred with Notch activation in multipotential cells, prior to the initiation of endocrine differentiation. It has not been established how direct activation of Notch in endocrine precursor cells affects their subsequent cell fate. Using conditional activation of Notch in cells expressing Neurogenin3 or NeuroD1, we examined the effects of Notch in both organs, on cell fate of early endocrine precursors and maturing endocrine-restricted cells, respectively. Notch did not preclude the differentiation of a limited number of endocrine cells in either organ when activated in Ngn3(+) precursor cells. In addition, in the pancreas most Ngn3(+) cells adopted a duct but not acinar cell fate; whereas in intestinal Ngn3(+) cells, Notch favored enterocyte and goblet cell fates, while selecting against endocrine and Paneth cell differentiation. A small fraction of NeuroD1(+) cells in the pancreas retain plasticity to respond to Notch, giving rise to intraislet ductules as well as cells with no detectable pancreatic lineage markers that appear to have limited ultrastructural features of both endocrine and duct cells. These results suggest that Notch directly regulates cell fate decisions in multipotential early endocrine precursor cells. Some maturing endocrine-restricted NeuroD1(+) cells in the pancreas switch to the duct lineage in response to Notch, indicating previously unappreciated plasticity at such a late stage of endocrine differentiation.

  10. Dynamic regulation of integrin activation by intracellular and extracellular signals controls oligodendrocyte morphology

    Directory of Open Access Journals (Sweden)

    Olsen Inger

    2005-11-01

    Full Text Available Abstract Background Myelination requires precise control of oligodendrocyte morphology and myelin generation at each of the axons contacted by an individual cell. This control must involve the integration of extracellular cues, such as those on the axon surface, with intrinsic developmental programmes. We asked whether integrins represent one class of oligodendrocyte cell-surface receptors able to provide this integration. Results Integrins signal via a process of activation, a conformational change that can be induced either by "outside-in" signals comprising physiological extracellular matrix ligands (mimicked by the pharmacological use of the divalent cation manganese or "inside-out" signalling molecules such as R-Ras. Increasing levels of outside-in signalling via the laminin receptor α6β1 integrin were found to promote oligodendrocyte processing and myelin sheet formation in culture. Similar results were obtained when inside-out signalling was increased by the expression of a constitutively-active R-Ras. Inhibiting inside-out signalling by using dominant-negative R-Ras reduces processes and myelin sheets; importantly, this can be partially rescued by the co-stimulation of outside-in signalling using manganese. Conclusion The balance of the equilibrium between active and inactive integrins regulates oligodendrocyte morphology, which is itself regulated by extrinsic and intrinsic cues so providing a mechanism of signal integration. As laminins capable of providing outside-in signals are present on axons at the time of myelination, a mechanism exists by which morphology and myelin generation might be regulated independently in each oligodendrocyte process.

  11. Protein tyrosine phosphatase receptor type z negatively regulates oligodendrocyte differentiation and myelination.

    Directory of Open Access Journals (Sweden)

    Kazuya Kuboyama

    Full Text Available BACKGROUND: Fyn tyrosine kinase-mediated down-regulation of Rho activity through activation of p190RhoGAP is crucial for oligodendrocyte differentiation and myelination. Therefore, the loss of function of its counterpart protein tyrosine phosphatase (PTP may enhance myelination during development and remyelination in demyelinating diseases. To test this hypothesis, we investigated whether Ptprz, a receptor-like PTP (RPTP expressed abuntantly in oligodendrocyte lineage cells, is involved in this process, because we recently revealed that p190RhoGAP is a physiological substrate for Ptprz. METHODOLOGY/PRINCIPAL FINDINGS: We found an early onset of the expression of myelin basic protein (MBP, a major protein of the myelin sheath, and early initiation of myelination in vivo during development of the Ptprz-deficient mouse, as compared with the wild-type. In addition, oligodendrocytes appeared earlier in primary cultures from Ptprz-deficient mice than wild-type mice. Furthermore, adult Ptprz-deficient mice were less susceptible to experimental autoimmune encephalomyelitis (EAE induced by active immunization with myelin/oligodendrocyte glycoprotein (MOG peptide than were wild-type mice. After EAE was induced, the tyrosine phosphorylation of p190RhoGAP increased significantly, and the EAE-induced loss of MBP was markedly suppressed in the white matter of the spinal cord in Ptprz-deficient mice. Here, the number of T-cells and macrophages/microglia infiltrating into the spinal cord did not differ between the two genotypes after MOG immunization. All these findings strongly support the validity of our hypothesis. CONCLUSIONS/SIGNIFICANCE: Ptprz plays a negative role in oligodendrocyte differentiation in early central nervous system (CNS development and remyelination in demyelinating CNS diseases, through the dephosphorylation of substrates such as p190RhoGAP.

  12. Hippocalcin Is Required for Astrocytic Differentiation through Activation of Stat3 in Hippocampal Neural Precursor Cells.

    Directory of Open Access Journals (Sweden)

    Min-Jeong Kang

    2016-10-01

    Full Text Available Hippocalcin (Hpca is a neuronal calcium sensor protein expressed in the mammalian brain. However, its function in neural stem/precursor cells has not yet been studied. Here, we clarify the function of Hpca in astrocytic differentiation in hippocampal neural precursor cells (HNPCs. When we overexpressed Hpca in HNPCs in the presence or absence of bFGF, expression levels of nerve-growth factors such as neurotrophin-3 (NT-3, neurotrophin-4/5 (NT-4/5 and brain-derived neurotrophic factor (BDNF, together with the proneural basic helix loop helix (bHLH transcription factors neuroD and neurogenin 1 (ngn1, increased significantly. In addition, there was an increase in the number of cells expressing glial fibrillary acidic protein (GFAP, an astrocyte marker, and in dendrite outgrowth, indicating astrocytic differentiation of the HNPCs. Downregulation of Hpca by transfection with Hpca siRNA reduced expression of NT-3, NT-4/5, BDNF, neuroD and ngn1 as well as levels of GFAP protein. Furthermore, overexpression of Hpca increased the phosphorylation of STAT3 (Ser727, and this effect was abolished by treatment with a STAT3 inhibitor (S3I-201, suggesting that STAT3 (Ser727 activation is involved in Hpca-mediated astrocytic differentiation. As expected, treatment with Stat3 siRNA or STAT3 inhibitor caused a complete inhibition of astrogliogenesis induced by Hpca overexpression. Taken together, this is the first report to show that Hpca, acting through Stat3, has an important role in the expression of neurotrophins and proneural bHLH transcription factors, and that it is an essential regulator of astrocytic differentiation and dendrite outgrowth in HNPCs.

  13. Effects of Ionizing Radiation and Glutathione Precursor on Antioxidant Enzyme and Cell Survival in Yeast

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jinkyu; Roh, Changhyun; Ryu, Taeho; Park, Jiyoung [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Nili, Michael A. [Oxiage Cosmeceutical Research Institute, Virginia (United States)

    2013-05-15

    Cells react to such an induced oxidative stress through scavenging the generated reactive oxygen species to reduce oxidative damage. Antioxidant enzymes such as glutathione peroxidase, catalase, and superoxide dismutase are immediately triggered for reactive oxygen species. N-acetyl-L-cysteine (NAC), a precursor of glutathione, is one of the antioxidants. The effect of NAC as an antioxidant and/or a cell rescue agent was investigated in the present study. Glutathione (GSH) is the most abundant intracellular thiol, which involves in antioxidant defense via direct interaction with ROS or via activities of detoxication enzymes like glutathione peroxidases (GPx). NAC flowed in the cell is converted to cysteine by deacetylation, that is supplied to the depleted GSH by oxidative stress. NAC prevents the depletion of GSH by radiation, increases the production of GSH, and improves enzymes activity such as GPx and alkaline phosphatase. Cell growth and survivorship and transcriptional level of glutathione gene are analyzed in two yeast strains exposed to combined treatment of NAC with gamma-rays. The effect of NAC on cell growth was measured during 72 hours. The cell growth was hampered by higher concentrations of NAC at stationary phase. NAC, however, didn't affect the cell division at the exponential phase. The survival of the cells decreased with radiation dose. The cell viability of the strain W303-1A was reduced significantly at the low dose (10 and 30 Gy). By comparison, the strain W303-1A was more sensitive to radiation with having a half lethal dose (LD{sub 50}) of about 20 Gy. The quantitative RT-PCR analysis showed that the transcriptional expression of antioxidant enzyme gene GPX1 increased after irradiation while the expression of the gene decreased by the combined treatment of NAC with 100 Gy radiation. The present study shows that NAC can directly scavenge ROS against oxidative stress in vivo. In conclusion, NAC can prevent radiation-induced oxidative

  14. Human Neural Precursor Cells Promote Neurologic Recovery in a Viral Model of Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Lu Chen

    2014-06-01

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

  15. Overexpression of amyloid precursor protein increases copper content in HEK293 cells

    Energy Technology Data Exchange (ETDEWEB)

    Suazo, Miriam; Hodar, Christian; Morgan, Carlos [INTA, Laboratorio de Bioinformatica y Expresion Genica, Universidad de Chile, El Libano 5524, Macul, Santiago (Chile); Cerpa, Waldo [Centro de Envejecimiento y Regeneracion (CARE), Centro de Regulacion Celular y Patologia ' Joaquin V. Luco' (CRCP), MIFAB, Departamento de Biologia Celular y Molecular, Facultad de Ciencias Biologicas, Pontificia Universidad Catolica de Chile, Santiago (Chile); Cambiazo, Veronica [INTA, Laboratorio de Bioinformatica y Expresion Genica, Universidad de Chile, El Libano 5524, Macul, Santiago (Chile); Millenium Nucleus CGC, Universidad de Chile (Chile); Inestrosa, Nibaldo C. [Centro de Envejecimiento y Regeneracion (CARE), Centro de Regulacion Celular y Patologia ' Joaquin V. Luco' (CRCP), MIFAB, Departamento de Biologia Celular y Molecular, Facultad de Ciencias Biologicas, Pontificia Universidad Catolica de Chile, Santiago (Chile); Gonzalez, Mauricio, E-mail: mgonzale@inta.cl [INTA, Laboratorio de Bioinformatica y Expresion Genica, Universidad de Chile, El Libano 5524, Macul, Santiago (Chile)

    2009-05-15

    Amyloid precursor protein (APP) is a transmembrane glycoprotein widely expressed in mammalian tissues and plays a central role in Alzheimer's disease. However, its physiological function remains elusive. Cu{sup 2+} binding and reduction activities have been described in the extracellular APP135-156 region, which might be relevant for cellular copper uptake and homeostasis. Here, we assessed Cu{sup 2+} reduction and {sup 64}Cu uptake in two human HEK293 cell lines overexpressing APP. Our results indicate that Cu{sup 2+} reduction increased and cells accumulated larger levels of copper, maintaining cell viability at supra-physiological levels of Cu{sup 2+} ions. Moreover, wild-type cells exposed to both Cu{sup 2+} ions and APP135-155 synthetic peptides increased copper reduction and uptake. Complementation of function studies in human APP751 transformed Fre1 defective Saccharomyces cerevisiae cells rescued low Cu{sup 2+} reductase activity and increased {sup 64}Cu uptake. We conclude that Cu{sup 2+} reduction activity of APP facilitates copper uptake and may represent an early step in cellular copper homeostasis.

  16. Sparing of extraocular muscle in aging and muscular dystrophies: A myogenic precursor cell hypothesis

    Energy Technology Data Exchange (ETDEWEB)

    Kallestad, Kristen M.; Hebert, Sadie L.; McDonald, Abby A.; Daniel, Mark L.; Cu, Sharon R.; McLoon, Linda K., E-mail: mcloo001@tc.umn.edu

    2011-04-01

    The extraocular muscles (EOM) are spared from pathology in aging and many forms of muscular dystrophy. Despite many studies, this sparing remains an enigma. The EOM have a distinct embryonic lineage compared to somite-derived muscles, and we have shown that they continuously remodel throughout life, maintaining a population of activated satellite cells even in aging. These data suggested the hypothesis that there is a population of myogenic precursor cells (mpcs) in EOM that is different from those in limb, with either elevated numbers of stem cells and/or mpcs with superior proliferative capacity compared to mpcs in limb. Using flow cytometry, EOM and limb muscle mononuclear cells were compared, and a number of differences were seen. Using two different cell isolation methods, EOM have significantly more mpcs per mg muscle than limb skeletal muscle. One specific subpopulation significantly increased in EOM compared to limb was positive for CD34 and negative for Sca-1, M-cadherin, CD31, and CD45. We named these the EOMCD34 cells. Similar percentages of EOMCD34 cells were present in both newborn EOM and limb muscle. They were retained in aged EOM, whereas the population decreased significantly in adult limb muscle and were extremely scarce in aged limb muscle. Most importantly, the percentage of EOMCD34 cells was elevated in the EOM from both the mdx and the mdx/utrophin{sup -/-} (DKO) mouse models of DMD and extremely scarce in the limb muscles of these mice. In vitro, the EOMCD34 cells had myogenic potential, forming myotubes in differentiation media. After determining a media better able to induce proliferation in these cells, a fusion index was calculated. The cells isolated from EOM had a 40% higher fusion index compared to the same cells isolated from limb muscle. The EOMCD34 cells were resistant to both oxidative stress and mechanical injury. These data support our hypothesis that the EOM may be spared in aging and in muscular dystrophies due to a

  17. Sparing of extraocular muscle in aging and muscular dystrophies: a myogenic precursor cell hypothesis.

    Science.gov (United States)

    Kallestad, Kristen M; Hebert, Sadie L; McDonald, Abby A; Daniel, Mark L; Cu, Sharon R; McLoon, Linda K

    2011-04-01

    The extraocular muscles (EOM) are spared from pathology in aging and many forms of muscular dystrophy. Despite many studies, this sparing remains an enigma. The EOM have a distinct embryonic lineage compared to somite-derived muscles, and we have shown that they continuously remodel throughout life, maintaining a population of activated satellite cells even in aging. These data suggested the hypothesis that there is a population of myogenic precursor cells (mpcs) in EOM that is different from those in limb, with either elevated numbers of stem cells and/or mpcs with superior proliferative capacity compared to mpcs in limb. Using flow cytometry, EOM and limb muscle mononuclear cells were compared, and a number of differences were seen. Using two different cell isolation methods, EOM have significantly more mpcs per mg muscle than limb skeletal muscle. One specific subpopulation significantly increased in EOM compared to limb was positive for CD34 and negative for Sca-1, M-cadherin, CD31, and CD45. We named these the EOMCD34 cells. Similar percentages of EOMCD34 cells were present in both newborn EOM and limb muscle. They were retained in aged EOM, whereas the population decreased significantly in adult limb muscle and were extremely scarce in aged limb muscle. Most importantly, the percentage of EOMCD34 cells was elevated in the EOM from both the mdx and the mdx/utrophin(-/-) (DKO) mouse models of DMD and extremely scarce in the limb muscles of these mice. In vitro, the EOMCD34 cells had myogenic potential, forming myotubes in differentiation media. After determining a media better able to induce proliferation in these cells, a fusion index was calculated. The cells isolated from EOM had a 40% higher fusion index compared to the same cells isolated from limb muscle. The EOMCD34 cells were resistant to both oxidative stress and mechanical injury. These data support our hypothesis that the EOM may be spared in aging and in muscular dystrophies due to a subpopulation

  18. Expression of feline immunodeficiency virus gag and env precursor proteins in Spodoptera frugiperda cells and their use in immunodiagnosis

    NARCIS (Netherlands)

    Horzinek, M.C.; Verschoor, E.J.; Vliet, A.L.W. van; Egberink, H.F.; Hesselink, W.; Ronde, A. de

    1993-01-01

    The gag and env genes of the feline immunodeficiency virus strain UT113 were cloned into a baculovirus transfer vector. The recombinant plasmids were used to create recombinant baculoviruses that expressed either the gag or the env precursor protein in insect cells (Sf9 cells). Leader sequence

  19. Expression of feline immunodeficiency virus gag and env precursor proteins in Spodoptera frugiperda cells and their use in immunodiagnosis

    NARCIS (Netherlands)

    Horzinek, M.C.; Verschoor, E.J.; Vliet, A.L.W. van; Egberink, H.F.; Hesselink, W.; Ronde, A. de

    1993-01-01

    The gag and env genes of the feline immunodeficiency virus strain UT113 were cloned into a baculovirus transfer vector. The recombinant plasmids were used to create recombinant baculoviruses that expressed either the gag or the env precursor protein in insect cells (Sf9 cells). Leader sequence cleav

  20. Expression of feline immunodeficiency virus gag and env precursor proteins in Spodoptera frugiperda cells and their use in immunodiagnosis

    NARCIS (Netherlands)

    Horzinek, M.C.; Verschoor, E.J.; Vliet, A.L.W. van; Egberink, H.F.; Hesselink, W.; Ronde, A. de

    1993-01-01

    The gag and env genes of the feline immunodeficiency virus strain UT113 were cloned into a baculovirus transfer vector. The recombinant plasmids were used to create recombinant baculoviruses that expressed either the gag or the env precursor protein in insect cells (Sf9 cells). Leader sequence cleav

  1. Transient expression of a mitochondrial precursor protein - A new approach to study mitochondrial protein import in cells of higher eukaryotes

    NARCIS (Netherlands)

    Huckriede, A; Heikema, A; Wilschut, J; Agsteribbe, E

    1996-01-01

    In order to study mitochondrial protein import in the context of whole cell metabolism, we have used the transfection technique based on Semliki Forest virus (SFV) to express a mitochondrial precursor protein within BHK21 cells and human fibroblasts. Recombinant SFV particles mediate a highly effici

  2. ON THE IMPROVEMENT OF THE PODOPHYLLOTOXIN PRODUCTION BY PHENYLPROPANOID PRECURSOR FEEDING TO CELL-CULTURES OF PODOPHYLLUM-HEXANDRUM ROYLE

    NARCIS (Netherlands)

    VANUDEN, W; PRAS, N; MALINGRE, TM

    1990-01-01

    In order to improve the production of the cytotoxic lignan podophyllotoxin, seven precursors from the phenylpropanoid-routing and one related compound were fed to cell suspension cultures derived from the rhizomes of Podophyllum hexandrum Royle. These cell cultures were able to convert only coniferi

  3. Increase of precursor frequency and clonal size of murine IgE-secreting cells by IL-4

    NARCIS (Netherlands)

    Savelkoul, H.F.J.; Lebman, D.A.; Benner, R.; Coffman, R.L.

    1988-01-01

    IL-4 is able to preferentially enhance murine IgE levels in the supernatant of LPS-stimulated T cell-depleted splenic B cell cultures. Clonal and quantitative analysis of this response revealed that this is due partly to a 14-fold increased IgE precursor frequency and partly to a three-fold increase

  4. PRDM6 is enriched in vascular precursors during development and inhibits endothelial cell proliferation, survival, and differentiation.

    Science.gov (United States)

    Wu, Yaxu; Ferguson, James E; Wang, Hong; Kelley, Rusty; Ren, Rongqin; McDonough, Holly; Meeker, James; Charles, Peter C; Wang, Hengbin; Patterson, Cam

    2008-01-01

    The mechanisms that regulate the differentiation program of multipotential stem cells remain poorly understood. In order to define the cues that delineate endothelial commitment from precursors, we screened for candidate regulatory genes in differentiating mouse embryoid bodies. We found that the PR/SET domain protein, PRDM6, is enriched in flk1(+) hematovascular precursor cells using a microarray-based approach. As determined by 5' RACE, full-length PRDM6 protein contains a PR domain and four Krüppel-like zinc fingers. In situ hybridization in mouse embryos demonstrates staining of the primitive streak, allantois, heart, outflow tract, paraaortic splanchnopleura (P-Sp)/aorto-gonadal-mesonephric (AGM) region and yolk sac, all sites known to be enriched in vascular precursor cells. PRDM6 is also detected in embryonic and adult-derived endothelial cell lines. PRDM6 is co-localized with histone H4 and methylates H4-K20 (but not H3) in vitro and in vivo, which is consistent with the known participation of PR domains in histone methyltransferase activity. Overexpression of PRDM6 in mouse embryonic endothelial cells induces apoptosis by activating caspase-3 and inducing G1 arrest. PRDM6 inhibits cell proliferation as determined by BrdU incorporation in endothelial cells, but not in rat aortic smooth muscle cells. Overexpression of PRDM6 also results in reduced tube formation in cultured endothelial cells grown in Matrigel. Taken together, our data indicate that PRDM6 is expressed by vascular precursors, has differential effects in endothelial cells and smooth muscle cells, and may play a role in vascular precursor differentiation and survival by modulating local chromatin-remodeling activity within hematovascular subpopulations during development.

  5. The planar cell polarity protein Strabismus promotes Pins anterior localization during asymmetric division of sensory organ precursor cells in Drosophila.

    Science.gov (United States)

    Bellaïche, Yohanns; Beaudoin-Massiani, Olivia; Stuttem, Isabella; Schweisguth, François

    2004-01-01

    Cell fate diversity is generated in part by the unequal segregation of cell-fate determinants during asymmetric cell division. In the Drosophila bristle lineage, the sensory organ precursor (pI) cell is polarized along the anteroposterior (AP) axis by Frizzled (Fz) receptor signaling. We show here that Fz localizes at the posterior apical cortex of the pI cell prior to mitosis, whereas Strabismus (Stbm) and Prickle (Pk), which are also required for AP polarization of the pI cell, co-localize at the anterior apical cortex. Thus, asymmetric localization of Fz, Stbm and Pk define two opposite cortical domains prior to mitosis of the pI cell. At mitosis, Stbm forms an anterior crescent that overlaps with the distribution of Partner of Inscuteable (Pins) and Discs-large (Dlg), two components of the anterior Dlg-Pins-Galphai complex that regulates the localization of cell-fate determinants. At prophase, Stbm promotes the anterior localization of Pins. By contrast, Dishevelled (Dsh) acts antagonistically to Stbm by excluding Pins from the posterior cortex. We propose that the Stbm-dependent recruitment of Pins at the anterior cortex of the pI cell is a novel read-out of planar cell polarity.

  6. Interferon gamma and sonic hedgehog signaling are required to dysregulate murine neural stem/precursor cells.

    Directory of Open Access Journals (Sweden)

    Janine Walter

    Full Text Available BACKGROUND: The pro-inflammatory cytokine interferon gamma (IFNγ, a key player in various neurological diseases, was recently shown to induce a dysregulated phenotype in neural stem/precursor cells (NSPCs that is characterized by the simultaneous expression of glial and neuronal markers and irregular electrophysiological properties. Thus far, the mechanisms of this phenomenon have remained unclear. METHODOLOGY/PRINCIPAL FINDINGS: To determine if binding of the signal transducers and activators of transcription (Stat 1 to the sonic hedgehog (SHH promoter is important for this phenomenon to occur, chromatin immunoprecipitation and pharmacological inhibition studies were performed. We report here that the activation of both the Stat 1 and SHH pathways is necessary to elicit the dysregulated phenotype. CONCLUSIONS/SIGNIFICANCE: Thus, blocking these pathways might preserve functional differentiation of NSPCs under inflammatory conditions leading to more effective regeneration.

  7. Efficiency Enhancement of Perovskite Solar Cells by Pumping Away the Solvent of Precursor Film Before Annealing

    Science.gov (United States)

    Xu, Qing-Yang; Yuan, Da-Xing; Mu, Hao-Ran; Igbari, Femi; Bao, Qiaoliang; Liao, Liang-Sheng

    2016-05-01

    A new approach to improve the quality of MAPbI3 - x Cl x perovskite film was demonstrated. It involves annealing the precursor film after pumping away the solvent, which can decrease the influence of solvent evaporation rate for the growth of the MAPbI3 - x Cl x perovskite film. The resulting film showed improved morphology, stronger absorption, fewer crystal defects, and smaller charge transfer resistance. The corresponding device demonstrated enhanced performance when compared with a reference device. The averaged value of power conversion efficiency increased from 10.61 to 12.56 %, and a champion efficiency of 14.0 % was achieved. This work paves a new way to improve the efficiency of perovskite solar cells.

  8. Different mechanisms must be considered to explain the increase in hippocampal neural precursor cell proliferation by physical activity

    Directory of Open Access Journals (Sweden)

    Rupert W Overall

    2016-08-01

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

  9. Dual-Source Precursor Approach for Highly Efficient Inverted Planar Heterojunction Perovskite Solar Cells.

    Science.gov (United States)

    Luo, Deying; Zhao, Lichen; Wu, Jiang; Hu, Qin; Zhang, Yifei; Xu, Zhaojian; Liu, Yi; Liu, Tanghao; Chen, Ke; Yang, Wenqiang; Zhang, Wei; Zhu, Rui; Gong, Qihuang

    2017-05-01

    The highest efficiencies reported for perovskite solar cells so far have been obtained mainly with methylammonium and formamidinium mixed cations. Currently, high-quality mixed-cation perovskite thin films are normally made by use of antisolvent protocols. However, the widely used "antisolvent"-assisted fabrication route suffers from challenges such as poor device reproducibility, toxic and hazardous organic solvent, and incompatibility with scalable fabrication process. Here, a simple dual-source precursor approach is developed to fabricate high-quality and mirror-like mixed-cation perovskite thin films without involving additional antisolvent process. By integrating the perovskite films into the planar heterojunction solar cells, a power conversion efficiency of 20.15% is achieved with negligible current density-voltage hysteresis. A stabilized power output approaching 20% is obtained at the maximum power point. These results shed light on fabricating highly efficient perovskite solar cells via a simple process, and pave the way for solar cell fabrication via scalable methods in the near future. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Semaphorin 3F and Neuropilin-2 Control the Migration of Human T-Cell Precursors

    Science.gov (United States)

    Asnafi, Vahid; Baleydier, Frederic; Messias, Carolina Valença; Lepelletier, Yves; Bedjaoui, Nawel; Renand, Amedée; Smaniotto, Salete; Canioni, Danielle; Milpied, Pierre; Balabanian, Karl; Bousso, Philippe; Leprêtre, Stéphane; Bertrand, Yves; Dombret, Hervé; Ifrah, Norbert; Dardenne, Mireille; Macintyre, Elizabeth; Savino, Wilson; Hermine, Olivier

    2014-01-01

    Neuropilins and semaphorins are known as modulators of axon guidance, angiogenesis, and organogenesis in the developing nervous system, but have been recently evidenced as also playing a role in the immune system. Here we describe the expression and role of semaphorin 3F (SEMA3F) and its receptor neuropilin-2 (NRP2) in human T cell precursors. NRP2 and SEMA3F are expressed in the human thymus, in both lymphoid and non-lymphoid compartments. SEMA3F have a repulsive effect on thymocyte migration and inhibited CXCL12- and sphingosine-1-phosphate (S1P)-induced thymocyte migration by inhibiting cytoskeleton reorganization prior to stimuli. Moreover, NRP2 and SEMA3F are expressed in human T-cell acute lymphoblastic leukemia/lymphoma primary cells. In these tumor cells, SEMA3F also blocks their migration induced by CXCL12 and S1P. Our data show that SEMA3F and NRP2 are further regulators of human thymocyte migration in physiological and pathological conditions. PMID:25068647

  11. Triazole RGD antagonist reverts TGFβ1-induced endothelial-to-mesenchymal transition in endothelial precursor cells.

    Science.gov (United States)

    Bianchini, Francesca; Peppicelli, Silvia; Fabbrizzi, Pierangelo; Biagioni, Alessio; Mazzanti, Benedetta; Menchi, Gloria; Calorini, Lido; Pupi, Alberto; Trabocchi, Andrea

    2017-01-01

    Fibrosis is the dramatic consequence of a dysregulated reparative process in which activated fibroblasts (myofibroblasts) and Transforming Growth Factor β1 (TGFβ1) play a central role. When exposed to TGFβ1, fibroblast and epithelial cells differentiate in myofibroblasts; in addition, endothelial cells may undergo endothelial-to-mesenchymal transition (EndoMT) and actively participate to the progression of fibrosis. Recently, the role of αv integrins, which recognize the Arg-Gly-Asp (RGD) tripeptide, in the release and signal transduction activation of TGFβ1 became evident. In this study, we present a class of triazole-derived RGD antagonists that interact with αvβ3 integrin. Above different compounds, the RGD-2 specifically interferes with integrin-dependent TGFβ1 EndoMT in Endothelial Colony-Forming Cells (ECPCs) derived from circulating Endothelial Precursor Cells (ECPCs). The RGD-2 decreases the amount of membrane-associated TGFβ1, and reduces both ALK5/TGFβ1 type I receptor expression and Smad2 phosphorylation in ECPCs. We found that RGD-2 antagonist reverts EndoMT, reducing α-smooth muscle actin (α-SMA) and vimentin expression in differentiated ECPCs. Our results outline the critical role of integrin in fibrosis progression and account for the opportunity of using integrins as target for anti-fibrotic therapeutic treatment.

  12. NFIL3 Orchestrates the Emergence of Common Helper Innate Lymphoid Cell Precursors

    Directory of Open Access Journals (Sweden)

    Wei Xu

    2015-03-01

    Full Text Available Innate lymphoid cells (ILCs are a family of effectors that originate from a common innate lymphoid cell progenitor. However, the transcriptional program that sets the identity of the ILC lineage remains elusive. Here, we show that NFIL3 is a critical regulator of the common helper-like innate lymphoid cell progenitor (CHILP. Cell-intrinsic Nfil3 ablation led to variably impaired development of fetal and adult ILC subsets. Conditional gene targeting demonstrated that NFIL3 exerted its function prior to ILC subset commitment. Accordingly, NFIL3 ablation resulted in loss of ID2+ CHILP and PLZF+ ILC progenitors. Nfil3 expression in lymphoid progenitors was under the control of the mesenchyme-derived hematopoietin IL-7, and NFIL3 exerted its function via direct Id2 regulation in the CHILP. Moreover, ectopic Id2 expression in Nfil3-null precursors rescued defective ILC lineage development in vivo. Our data establish NFIL3 as a key regulator of common helper-like ILC progenitors as they emerge during early lymphopoiesis.

  13. A synergistic approach for neural repair: cell transplantation and induction of endogenous precursor cell activity.

    Science.gov (United States)

    Madhavan, Lalitha; Collier, Timothy J

    2010-05-01

    Stem cell research offers enormous potential for treating many diseases of the nervous system. At present, therapeutic strategies in stem cell research segregate into two approaches: cell transplantation or endogenous cell stimulation. Realistically, future cell therapies will most likely involve a combination of these two approaches, a theme of our current research. Here, we propose that there exists a 'synergy' between exogenous (transplanted) and endogenous stem cell actions that can be utilized to achieve therapeutic ends. Elucidating mechanisms underlying this exogenous-endogenous stem cell synergism may lead to the development of optimal cell therapies for neural disorders. Copyright 2009 Elsevier Ltd. All rights reserved.

  14. Behaviour of oligodendrocytes and Schwann cells in an experimental model of toxic demyelination of the central nervous system Comportamento de oligodendrócitos e células de Schwann em modelo experimental de desmielinização tóxica do sistema nervoso central

    Directory of Open Access Journals (Sweden)

    Dominguita Lühers Graça

    2001-06-01

    Full Text Available Oligodendrocytes and Schwann cells are engaged in myelin production, maintenance and repairing respectively in the central nervous system (CNS and the peripheral nervous system (PNS. Whereas oligodendrocytes act only within the CNS, Schwann cells are able to invade the CNS in order to make new myelin sheaths around demyelinated axons. Both cells have some limitations in their activities, i.e. oligodendrocytes are post-mitotic cells and Schwann cells only get into the CNS in the absence of astrocytes. Ethidium bromide (EB is a gliotoxic chemical that when injected locally within the CNS, induce demyelination. In the EB model of demyelination, glial cells are destroyed early after intoxication and Schwann cells are free to approach the naked central axons. In normal Wistar rats, regeneration of lost myelin sheaths can be achieved as early as thirteen days after intoxication; in Wistar rats immunosuppressed with cyclophosphamide the process is delayed and in rats administered cyclosporine it may be accelerated. Aiming the enlightening of those complex processes, all events concerning the myelinating cells in an experimental model are herein presented and discussed.Oligodendrócitos e células de Schwann realizam a produção e manutenção das bainhas de mielina, respectivamente no sistema nervoso central (SNC e periférico (SNP. As células de Schwann, à diferença dos oligodendrócitos, são capazes de invadir o SNC para remielinizar axônios desmielinizados, sempre que os astrócitos tenham sido destruídos. O brometo de etídio é uma droga gliotóxica usada para induzir desmielinização com o desaparecimento precoce de astrócitos, de modo que as células de Schwann têm liberdade para invadir o SNC. Em ratos Wistar normais, a remielinização é detectada treze dias após desmielinização; em ratos Wistar imunossuprimidos com ciclofosfamida a reparação do tecido é tardia, enquanto que em animais tratados com ciclosporina ela

  15. Precursor B-cell acute lymphoblastic leukemia presenting as obstructive jaundice: a case report

    Directory of Open Access Journals (Sweden)

    Awasum Michael

    2011-07-01

    Full Text Available Abstract Introduction Acute leukemias very rarely present with jaundice. Herein we report a case of precursor B-cell acute lymphoblastic leukemia that presented with jaundice in an adult. Case presentation A 44-year-old Hispanic man presented with right upper quadrant abdominal pain and jaundice. His initial blood work revealed pancytopenia and hyperbilirubinemia. Direct bilirubin was more than 50% of the total. His imaging studies were unremarkable except for hepatomegaly. All blood screening tests for various hepatocellular etiologies were normal. A diagnosis of precursor B-cell acute lymphoblastic leukemia was made upon liver biopsy. It also showed lymphocytic infiltration of the hepatic parenchyma leading to bile stasis. The diagnosis was subsequently confirmed upon bone marrow biopsy. The patient was treated with a hyperfractionated cyclophosphamide/vincristine/doxorubicin/dexamethasone regimen. Conclusion Acute lymphoblastic leukemia should be one of the differential diagnoses that should be considered when initial work-up for jaundice is inconclusive. Some cases of acute lymphoblastic leukemia have been reported in both adults and children to have presented with the initial manifestation of jaundice, but only a few had no radiographic evidence of biliary obstruction. Such presentation can pose a serious diagnostic dilemma for clinicians. This manuscript attempts to highlight it. Moreover, we believe that if acute lymphoblastic leukemia presentations similar to this case continue to be reported in adults or children, a specific immunophenotypic expression and cytogenetic abnormality may be found to be associated with hepatic infiltration by leukemia. This may substantially contribute to the further understanding of the pathophysiology of this hematologic disease.

  16. LINGO-1 Regulates Oligodendrocyte Differentiation through the Cytoplasmic Gelsolin Signaling Pathway.

    Science.gov (United States)

    Shao, Zhaohui; Lee, Xinhua; Huang, Guanrong; Sheng, Guoqing; Henderson, Christopher E; Louvard, Daniel; Sohn, Jiho; Pepinsky, Blake; Mi, Sha

    2017-03-22

    Differentiation and maturation of oligodendrocyte progenitor cells (OPCs) involve the assembly and disassembly of actin microfilaments. However, how actin dynamics are regulated during this process remains poorly understood. Leucine-rich repeat and Ig-like domain-containing Nogo receptor interacting protein 1 (LINGO-1) is a negative regulator of OPC differentiation. We discovered that anti-LINGO-1 antibody-promoted OPC differentiation was accompanied by upregulation of cytoplasmic gelsolin (cGSN), an abundant actin-severing protein involved in the depolymerization of actin filaments. Treating rat OPCs with cGSN siRNA reduced OPC differentiation, whereas overexpression of cGSN promoted OPC differentiation in vitro and remyelination in vivo Furthermore, coexpression of cGSN and LINGO-1 blocked the inhibitory effect of LINGO-1. Our study demonstrates that cGSN works downstream of LINGO-1 signaling pathway, which enhances actin dynamics and is essential for OPC morphogenesis and differentiation. This finding may lead to novel therapeutic approaches for the treatment of demyelinating diseases such as multiple sclerosis (MS).SIGNIFICANCE STATEMENT Myelin loss and subsequent axon degeneration contributes to a variety of neurological diseases, such as multiple sclerosis (MS). Understanding the regulation of myelination by oligodendrocytes is therefore critical for developing therapies for the treatment of MS. We previously demonstrated that leucine-rich repeat and Ig-like domain-containing Nogo receptor interacting protein 1 (LINGO-1) is a negative regulator of oligodendrocyte differentiation and that anti-LINGO-1 promotes remyelination in preclinical animal models for MS and in a phase II acute optic neuritis clinical trial (RENEW). The mechanism by which LINGO-1 regulates oligodendrocyte differentiation is unknown. Here, we demonstrate that LINGO-1 regulates oligodendrocyte differentiation and maturation through the cytoplasmic gelsolin signaling pathway, providing new

  17. Gas6 increases myelination by oligodendrocytes and its deficiency delays recovery following cuprizone-induced demyelination.

    Directory of Open Access Journals (Sweden)

    Michele D Binder

    Full Text Available Multiple sclerosis (MS is a complex demyelinating disease of the central nervous system. Current research has shown that at least in some cases, the primary insult in MS could be directed at the oligodendrocyte, and that the earliest immune responses are primarily via innate immune cells. We have identified a family of receptor protein tyrosine kinases, known as the TAM receptors (Tyro3, Axl and Mertk, as potentially important in regulating both the oligodendrocyte and immune responses. We have previously shown that Gas6, a ligand for the TAM receptors, can affect the severity of demyelination in mice, with a loss of signalling via Gas6 leading to decreased oligodendrocyte survival and increased microglial activation during cuprizone-induced demyelination. We hypothesised TAM receptor signalling would also influence the extent of recovery in mice following demyelination. A significant effect of the absence of Gas6 was detected upon remyelination, with a lower level of myelination after 4 weeks of recovery in comparison with wild-type mice. The delay in remyelination was accompanied by a reduction in oligodendrocyte numbers. To understand the molecular mechanisms that drive the observed effects, we also examined the effect of exogenous Gas6 in in vitro myelination assays. We found that Gas6 significantly increased myelination in a dose-dependent manner, suggesting that TAM receptor signalling could be directly involved in myelination by oligodendrocytes. The reduced rate of remyelination in the absence of Gas6 could thus result from a lack of Gas6 at a critical time during myelin production after injury. These findings establish Gas6 as an important regulator of both CNS demyelination and remyelination.

  18. Translation of myelin basic protein mRNA in oligodendrocytes is regulated by integrin activation and hnRNP-K

    DEFF Research Database (Denmark)

    Laursen, Lisbeth Schmidt; Chan, Colin W; ffrench-Constant, Charles

    2011-01-01

    Myelination in the central nervous system provides a unique example of how cells establish asymmetry. The myelinating cell, the oligodendrocyte, extends processes to and wraps multiple axons of different diameter, keeping the number of wraps proportional to the axon diameter. Local regulation...... translation of a key sheath protein, myelin basic protein (MBP), by reversing the inhibitory effect of the mRNA 3′UTR. During oligodendrocyte differentiation and myelination α6β1-integrin interacts with hnRNP-K, an mRNA-binding protein, which binds to MBP mRNA and translocates from the nucleus to the myelin...

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

    Energy Technology Data Exchange (ETDEWEB)

    Boku, Shuken, E-mail: shuboku@med.hokudai.ac.jp [Department of Psychiatry, Hokkaido University Graduate School of Medicine, Sapporo (Japan); Nakagawa, Shin [Department of Psychiatry, Hokkaido University Graduate School of Medicine, Sapporo (Japan); Takamura, Naoki [Pharmaceutical Laboratories, Dainippon Sumitomo Pharma Co. Ltd., Osaka (Japan); Kato, Akiko [Department of Psychiatry, Hokkaido University Graduate School of Medicine, Sapporo (Japan); Takebayashi, Minoru [Department of Psychiatry, National Hospital Organization Kure Medical Center, Kure (Japan); Hisaoka-Nakashima, Kazue [Department of Pharmacology, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima (Japan); Omiya, Yuki; Inoue, Takeshi; Kusumi, Ichiro [Department of Psychiatry, Hokkaido University Graduate School of Medicine, Sapporo (Japan)

    2013-05-17

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

  20. Effect of oxygen tension on bioenergetics and proteostasis in young and old myoblast precursor cells

    Directory of Open Access Journals (Sweden)

    M. Konigsberg

    2013-01-01

    Full Text Available In the majority of studies using primary cultures of myoblasts, the cells are maintained at ambient oxygen tension (21% O2, despite the fact that physiological O2 at the tissue level in vivo is much lower (~1–5% O2. We hypothesized that the cellular response in presence of high oxygen concentration might be particularly important in studies comparing energetic function or oxidative stress in cells isolated from young versus old animals. To test this, we asked whether oxygen tension plays a role in mitochondrial bioenergetics (oxygen consumption, glycolysis and fatty acid oxidation or oxidative damage to proteins (protein disulfides, carbonyls and aggregates in myoblast precursor cells (MPCs isolated from young (3–4 m and old (29–30 m C57BL/6 mice. MPCs were grown under physiological (3% or ambient (21% O2 for two weeks prior to exposure to an acute oxidative insult (H2O2. Our results show significantly higher basal mitochondrial respiration in young versus old MPCs, an increase in basal respiration in young MPCs maintained at 3% O2 compared to cells maintained at 21% O2, and a shift toward glycolytic metabolism in old MPCs grown at 21% O2. H2O2 treatment significantly reduced respiration in old MPCs grown at 3% O2 but did not further repress respiration at 21% O2 in old MPCs. Oxidative damage to protein was higher in cells maintained at 21% O2 and increased in response to H2O2 in old MPCs. These data underscore the importance of understanding the effect of ambient oxygen tension in cell culture studies, in particular studies measuring oxidative damage and mitochondrial function.

  1. Highly efficient differentiation of neural precursors from human embryonic stem cells and benefits of transplantation after ischemic stroke in mice.

    Science.gov (United States)

    Drury-Stewart, Danielle; Song, Mingke; Mohamad, Osama; Guo, Ying; Gu, Xiaohuan; Chen, Dongdong; Wei, Ling

    2013-08-08

    Ischemic stroke is a leading cause of death and disability, but treatment options are severely limited. Cell therapy offers an attractive strategy for regenerating lost tissues and enhancing the endogenous healing process. In this study, we investigated the use of human embryonic stem cell-derived neural precursors as a cell therapy in a murine stroke model. Neural precursors were derived from human embryonic stem cells by using a fully adherent SMAD inhibition protocol employing small molecules. The efficiency of neural induction and the ability of these cells to further differentiate into neurons were assessed by using immunocytochemistry. Whole-cell patch-clamp recording was used to demonstrate the electrophysiological activity of human embryonic stem cell-derived neurons. Neural precursors were transplanted into the core and penumbra regions of a focal ischemic stroke in the barrel cortex of mice. Animals received injections of bromodeoxyuridine to track regeneration. Neural differentiation of the transplanted cells and regenerative markers were measured by using immunohistochemistry. The adhesive removal test was used to determine functional improvement after stroke and intervention. After 11 days of neural induction by using the small-molecule protocol, over 95% of human embryonic stem-derived cells expressed at least one neural marker. Further in vitro differentiation yielded cells that stained for mature neuronal markers and exhibited high-amplitude, repetitive action potentials in response to depolarization. Neuronal differentiation also occurred after transplantation into the ischemic cortex. A greater level of bromodeoxyuridine co-localization with neurons was observed in the penumbra region of animals receiving cell transplantation. Transplantation also improved sensory recovery in transplant animals over that in control animals. Human embryonic stem cell-derived neural precursors derived by using a highly efficient small-molecule SMAD inhibition

  2. The genetic basis of early T-cell precursor acute lymphoblastic leukaemia.

    Science.gov (United States)

    Zhang, Jinghui; Ding, Li; Holmfeldt, Linda; Wu, Gang; Heatley, Sue L; Payne-Turner, Debbie; Easton, John; Chen, Xiang; Wang, Jianmin; Rusch, Michael; Lu, Charles; Chen, Shann-Ching; Wei, Lei; Collins-Underwood, J Racquel; Ma, Jing; Roberts, Kathryn G; Pounds, Stanley B; Ulyanov, Anatoly; Becksfort, Jared; Gupta, Pankaj; Huether, Robert; Kriwacki, Richard W; Parker, Matthew; McGoldrick, Daniel J; Zhao, David; Alford, Daniel; Espy, Stephen; Bobba, Kiran Chand; Song, Guangchun; Pei, Deqing; Cheng, Cheng; Roberts, Stefan; Barbato, Michael I; Campana, Dario; Coustan-Smith, Elaine; Shurtleff, Sheila A; Raimondi, Susana C; Kleppe, Maria; Cools, Jan; Shimano, Kristin A; Hermiston, Michelle L; Doulatov, Sergei; Eppert, Kolja; Laurenti, Elisa; Notta, Faiyaz; Dick, John E; Basso, Giuseppe; Hunger, Stephen P; Loh, Mignon L; Devidas, Meenakshi; Wood, Brent; Winter, Stuart; Dunsmore, Kimberley P; Fulton, Robert S; Fulton, Lucinda L; Hong, Xin; Harris, Christopher C; Dooling, David J; Ochoa, Kerri; Johnson, Kimberly J; Obenauer, John C; Evans, William E; Pui, Ching-Hon; Naeve, Clayton W; Ley, Timothy J; Mardis, Elaine R; Wilson, Richard K; Downing, James R; Mullighan, Charles G

    2012-01-11

    Early T-cell precursor acute lymphoblastic leukaemia (ETP ALL) is an aggressive malignancy of unknown genetic basis. We performed whole-genome sequencing of 12 ETP ALL cases and assessed the frequency of the identified somatic mutations in 94 T-cell acute lymphoblastic leukaemia cases. ETP ALL was characterized by activating mutations in genes regulating cytokine receptor and RAS signalling (67% of cases; NRAS, KRAS, FLT3, IL7R, JAK3, JAK1, SH2B3 and BRAF), inactivating lesions disrupting haematopoietic development (58%; GATA3, ETV6, RUNX1, IKZF1 and EP300) and histone-modifying genes (48%; EZH2, EED, SUZ12, SETD2 and EP300). We also identified new targets of recurrent mutation including DNM2, ECT2L and RELN. The mutational spectrum is similar to myeloid tumours, and moreover, the global transcriptional profile of ETP ALL was similar to that of normal and myeloid leukaemia haematopoietic stem cells. These findings suggest that addition of myeloid-directed therapies might improve the poor outcome of ETP ALL.

  3. 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.

  4. c-jun is differentially expressed in embryonic and adult neural precursor cells.

    Science.gov (United States)

    Kawashima, Fumiaki; Saito, Kengo; Kurata, Hirofumi; Maegaki, Yoshihiro; Mori, Tetsuji

    2017-01-16

    c-jun, a major component of AP-1 transcription factor, has a wide variety of functions. In the embryonic brain, c-jun mRNA is abundantly expressed in germinal layers around the ventricles. Although the subventricular zone (SVZ) of the adult brain is a derivative of embryonic germinal layers and contains neural precursor cells (NPCs), the c-jun expression pattern is not clear. To study the function of c-jun in adult neurogenesis, we analyzed c-jun expression in the adult SVZ by immunohistochemistry and compared it with that of the embryonic brain. We found that almost all proliferating embryonic NPCs expressed c-jun, but the number of c-jun immunopositive cells among proliferating adult NPCs was about half. In addition, c-jun was hardly expressed in post-mitotic migrating neurons in the embryonic brain, but the majority of c-jun immunopositive cells were tangentially migrating neuroblasts heading toward the olfactory bulb in the adult brain. In addition, status epilepticus is known to enhance the transient proliferation of adult NPCs, but the c-jun expression pattern was not significantly affected. These expression patterns suggest that c-jun has a pivotal role in the proliferation of embryonic NPCs, but it has also other roles in adult neurogenesis.

  5. WIP1 modulates responsiveness to Sonic Hedgehog signaling in neuronal precursor cells and medulloblastoma

    Science.gov (United States)

    Wen, Jing; Lee, Juhyun; Malhotra, Anshu; Nahta, Rita; Arnold, Amanda R.; Buss, Meghan C.; Brown, Briana D.; Maier, Caroline; Kenney, Anna M.; Remke, Marc; Ramaswamy, Vijay; Taylor, Michael D.; Castellino, Robert C.

    2016-01-01

    High-level amplification of the protein phosphatase PPM1D (WIP1) is present in a subset of medulloblastomas (MBs) that have an expression profile consistent with active Sonic Hedgehog (SHH) signaling. We found that WIP1 overexpression increased expression of Shh target genes and cell proliferation in response to Shh stimulation in NIH3T3 and cerebellar granule neuron precursor (cGNP) cells in a p53-independent manner. Thus, we developed a mouse in which WIP1 is expressed in the developing brain under control of the Neurod2 promoter (ND2:WIP1). The external granule layer in early post-natal ND2:WIP1 mice exhibited increased proliferation and expression of Shh downstream targets. MB incidence increased and survival decreased when ND2:WIP1 mice were crossed with a Shh-activated MB mouse model. Conversely, Wip1 knock out significantly suppressed MB formation in two independent mouse models of Shh-activated MB. Furthermore, Wip1 knock-down or treatment with a WIP1 inhibitor suppressed the effects of Shh stimulation and potentiated the growth inhibitory effects of SHH pathway-inhibiting drugs in Shh-activated MB cells in vitro. This suggests an important cross-talk between SHH and WIP1 pathways that accelerates tumorigenesis and supports WIP1 inhibition as a potential treatment strategy for MB. PMID:27086929

  6. Effect of berberine on nitric oxide production during oxygen-glucose deprivation/reperfusion in OLN-93 oligodendrocytes.

    Science.gov (United States)

    Nadjafi, Shabnam; Ebrahimi, Soltan-Ahmad; Rahbar-Roshandel, Nahid

    2014-11-01

    In this study, the effect of berberine, an isoquinoline alkaloid isolated from Coptidis rhizoma, on Nitric Oxide (NO) production, as a possible involved factor, during excitotoxic injury in oligodendroglial cells were evaluated. The overactivation of ionotropic glutamate receptors which is known as the excitotoxicity, is an important phenomenon because of the contribution in acute injury to the central nervous system, chronic neurodegenerative disorders, oligodendrocyte loss and demyelinating diseases as Multiple Sclerosis (MS). Intracellular Ca2+ overload, have a key role during excitotoxic injury and such increase in cytoplasmic Ca2+ triggers a series of events such as production of NO that end to cell death. Previous report showed the protective effects of berberine on ischemic-induced excitotoxic insult in oligodendrocytes. Hereby, we intended to know if the NO production could be associated with oxygen-glucose deprivation/reperfusion-induced excitotoxic damage in oligodendrocyte; moreover, the alteration of NO production could be considered as an involved mechanism for protective effect of berberine in such condition. Therefore, the effect of berberine (2 μM) on NO production during oxygen-glucose deprivation/24 h reperfusion in oligodendrocytes were examined. The OLN-93 cell line (a permanent immature rat oligodendrocyte) was used as a model of oligodendrocyte. Thirty minutes-oxygen-glucose deprivation/24 h reperfusion was used to induce excitotoxicity. NO production was evaluated by Griess method. Our results demonstrated that berberine (2 μM) significantly decreased NO production during 30 min oxygen-glucose deprivation/reperfusion. It seems that blockade of NO production by berberine may also participate in oligodendroglial cell protection against oxygen-glucose deprivation/reperfusion-induced insult.

  7. Anchor cell signaling and vulval precursor cell positioning establish a reproducible spatial context during C. elegans vulval induction.

    Science.gov (United States)

    Grimbert, Stéphanie; Tietze, Kyria; Barkoulas, Michalis; Sternberg, Paul W; Félix, Marie-Anne; Braendle, Christian

    2016-08-01

    How cells coordinate their spatial positioning through intercellular signaling events is poorly understood. Here we address this topic using Caenorhabditis elegans vulval patterning during which hypodermal vulval precursor cells (VPCs) adopt distinct cell fates determined by their relative positions to the gonadal anchor cell (AC). LIN-3/EGF signaling by the AC induces the central VPC, P6.p, to adopt a 1° vulval fate. Exact alignment of AC and VPCs is thus critical for correct fate patterning, yet, as we show here, the initial AC-VPC positioning is both highly variable and asymmetric among individuals, with AC and P6.p only becoming aligned at the early L3 stage. Cell ablations and mutant analysis indicate that VPCs, most prominently 1° cells, move towards the AC. We identify AC-released LIN-3/EGF as a major attractive signal, which therefore plays a dual role in vulval patterning (cell alignment and fate induction). Additionally, compromising Wnt pathway components also induces AC-VPC alignment errors, with loss of posterior Wnt signaling increasing stochastic vulval centering on P5.p. Our results illustrate how intercellular signaling reduces initial spatial variability in cell positioning to generate reproducible interactions across tissues.

  8. From differentiation to proliferation: The secretory amyloid precursor protein as a local mediator of growth in thyroid epithelial cells

    OpenAIRE

    Pietrzik, Claus Ulrich; Hoffmann, Jens; Stöber, Kai; Chen, Chun-yan; Bauer, Christoph; Otero, Deborah A.C.; Roch, Jean-Marc; Herzog, Volker

    1998-01-01

    In various species, thyrotropin (TSH) is known to stimulate both differentiation and proliferation of thyroid follicle cells. This cell type has also been shown to express members of the Alzheimer amyloid precursor (APP) protein family and to release the secretory N-terminal domain of APP (sAPP) in a TSH-dependent fashion. In this study on binding to the cell surfaces, exogenously added recombinant sAPP stimulated phosphorylation mediated by mitogen-activated protein kinase and effectively ev...

  9. Co-expression of metalloproteinases 11 and 12 in cervical scrapes cells from cervical precursor lesions.

    Science.gov (United States)

    Valdivia, Alejandra; Peralta, Raúl; Matute-González, Manuel; García Cebada, Juan Manuel; Casasola, Ivonne; Jiménez-Medrano, Cristina; Aguado-Pérez, Rogelio; Villegas, Vanessa; González-Bonilla, Cesar; Manuel-Apolinar, Leticia; Ibáñez, Miguel; Salcedo, Mauricio

    2011-01-01

    The metalloproteinases (MMP) 11 and 12 have been shown to be expressed in cervical cancer (CC). In order to extend our previous results, these MMPs were evaluated in cervical precursor lesions. One hundred seventeen cervical scrapes: thirty-six normal, thirty-six low grade squamous lesions (LSIL), thirty-six high grade (HSIL), nine CC; and, also ninety-nine paraffin-embedded cervical lesions: fifteen normal cervices, thirty eight LSIL, sixteen HSIL, and five CC were collected. The samples were analyzed for relative expression by real time RT-PCR or immunohistochemistry assay. We were able to identify a relative increased expression of MMP11 in 75% and 78% from LSIL and HSIL samples, respectively. While MMP12 expression was 64% and 75% in LSIL and HSIL, respectively. Positive samples for MMP11 expression were also positive for MMP12 expression and also increased according to illness progression. In the tissues, MMP11 or MMP12 expression was observed in the cytoplasm of the neoplastic cells, while in the normal epithelium was absent. The reaction was always stronger for MMP12 than MMP11. MMP11 expression was present in 77% and 66% of LSIL and HSIL, while MMP12 expression was 73% and 68%. There was a relationship between MMP11 or MMP12 expression and HPV infection. Our data are showing a relationship between diagnostic of precursor lesions and the MMP11 and 12 expressions, suggesting that their expression could be an early event in the neoplastic lesions of the cervix and could have clinical significance.

  10. Sequence conservation and combinatorial complexity of Drosophila neural precursor cell enhancers

    Directory of Open Access Journals (Sweden)

    Kuzin Alexander

    2008-08-01

    Full Text Available Abstract Background The presence of highly conserved sequences within cis-regulatory regions can serve as a valuable starting point for elucidating the basis of enhancer function. This study focuses on regulation of gene expression during the early events of Drosophila neural development. We describe the use of EvoPrinter and cis-Decoder, a suite of interrelated phylogenetic footprinting and alignment programs, to characterize highly conserved sequences that are shared among co-regulating enhancers. Results Analysis of in vivo characterized enhancers that drive neural precursor gene expression has revealed that they contain clusters of highly conserved sequence blocks (CSBs made up of shorter shared sequence elements which are present in different combinations and orientations within the different co-regulating enhancers; these elements contain either known consensus transcription factor binding sites or consist of novel sequences that have not been functionally characterized. The CSBs of co-regulated enhancers share a large number of sequence elements, suggesting that a diverse repertoire of transcription factors may interact in a highly combinatorial fashion to coordinately regulate gene expression. We have used information gained from our comparative analysis to discover an enhancer that directs expression of the nervy gene in neural precursor cells of the CNS and PNS. Conclusion The combined use EvoPrinter and cis-Decoder has yielded important insights into the combinatorial appearance of fundamental sequence elements required for neural enhancer function. Each of the 30 enhancers examined conformed to a pattern of highly conserved blocks of sequences containing shared constituent elements. These data establish a basis for further analysis and understanding of neural enhancer function.

  11. Role of serum angiopoietin-2 level in screening for esophageal squamous cell cancer and its precursors

    Institute of Scientific and Technical Information of China (English)

    ZHOU Ying-zhi; FANG Xue-qiang; LI Hao; DIAO Yu-tao; YANG Yan-fang; ZHAO De-li; WU Kan; LI Hui-qing

    2007-01-01

    Background Angiopoietin-2 (Ang-2) is one of the critical regulators of tumor angiogenesis. Studies have shown a significant correlation of Ang-2 expression to tumor invasion and metastasis in various human cancers, but little is known about the serum Ang-2 (sAng-2) levels in esophageal squamous cell cancer (ESCC) and its precursors. In this study, we aimed to investigate its role in screening for ESCC and its precursors.Methods We carried out a free endoscopic screening in Feicheng City, a high ESCC incidence area in Shandong Province of China. Serum samples were collected as follows: 91 from normal subjects, 44 from patients with esophagitis,85 from patients with hyperplasia, and 13 from patients with early ESCC. In addition, 28 serum samples were obtained from patients with invasive ESCC undergoing surgery in People's Hospital of Feicheng City. All the subjects of the five groups were diagnosed by histopathology. The sAng-2 levels were tested and compared, and the diagnostic power in early or/and invasive ESCC was calculated in terms of sensitivity and other parameters.Results The sAng-2 levels were (22.0±5.5), (21.3±3.2), (20.5±3.3), (24.0±5.0), and (29.8±5.0) U/ml in normal,esophagitis, hyperplasia, early ESCC, and invasive ESCC groups respectively. It was significantly higher in early ESCC than inhyperplasia group (P=0.009). The invasive ESCC group showed the highest Ang-2 level among all groups (all P=0.000). The sensitivities of sAng-2 to early and invasive ESCC were 23.1% and 78.6% respectively.Conclusion sAng-2 level is related to carcinogenesis and progression of ESCC, but it can not be used to screen for early ESCC.

  12. Post-embryonic nerve-associated precursors to adult pigment cells: genetic requirements and dynamics of morphogenesis and differentiation.

    Directory of Open Access Journals (Sweden)

    Erine H Budi

    2011-05-01

    Full Text Available The pigment cells of vertebrates serve a variety of functions and generate a stunning variety of patterns. These cells are also implicated in human pathologies including melanoma. Whereas the events of pigment cell development have been studied extensively in the embryo, much less is known about morphogenesis and differentiation of these cells during post-embryonic stages. Previous studies of zebrafish revealed genetically distinct populations of embryonic and adult melanophores, the ectotherm homologue of amniote melanocytes. Here, we use molecular markers, vital labeling, time-lapse imaging, mutational analyses, and transgenesis to identify peripheral nerves as a niche for precursors to adult melanophores that subsequently migrate to the skin to form the adult pigment pattern. We further identify genetic requirements for establishing, maintaining, and recruiting precursors to the adult melanophore lineage and demonstrate novel compensatory behaviors during pattern regulation in mutant backgrounds. Finally, we show that distinct populations of latent precursors having differential regenerative capabilities persist into the adult. These findings provide a foundation for future studies of post-embryonic pigment cell precursors in development, evolution, and neoplasia.

  13. Functional electrical stimulation-facilitated proliferation and regeneration of neural precursor cells in the brains of rats with cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    Yun Xiang; Huihua Liu; Tiebin Yan; Zhiqiang Zhuang; Dongmei Jin; Yuan Peng

    2014-01-01

    Previous studies have shown that proliferation of endogenous neural precursor cells cannot alone compensate for the damage to neurons and axons. From the perspective of neural plastici-ty, we observed the effects of functional electrical stimulation treatment on endogenous neural precursor cell proliferation and expression of basic fibroblast growth factor and epidermal growth factor in the rat brain on the infarct side. Functional electrical stimulation was performed in rat models of acute middle cerebral artery occlusion. Simultaneously, we set up a placebo stimulation group and a sham-operated group. Immunohistochemical staining showed that, at 7 and 14 days, compared with the placebo group, the numbers of nestin (a neural precursor cell marker)-positive cells in the subgranular zone and subventricular zone were increased in the functional electrical stimulation treatment group. Western blot assays and reverse-transcription PCR showed that total protein levels and gene expression of epidermal growth factor and basic ifbroblast growth factor were also upregulated on the infarct side. Prehensile traction test results showed that, at 14 days, prehension function of rats in the functional electrical stimulation group was signiifcantly better than in the placebo group. These results suggest that functional electrical stimulation can promote endogenous neural precursor cell proliferation in the brains of acute cerebral infarction rats, enhance expression of basic fibroblast growth factor and epidermal growth factor, and improve the motor function of rats.

  14. Modeling and analysis of retinoic acid induced differentiation of uncommitted precursor cells.

    Science.gov (United States)

    Tasseff, Ryan; Nayak, Satyaprakash; Song, Sang Ok; Yen, Andrew; Varner, Jeffrey D

    2011-05-01

    Manipulation of differentiation programs has therapeutic potential in a spectrum of human cancers and neurodegenerative disorders. In this study, we integrated computational and experimental methods to unravel the response of a lineage uncommitted precursor cell-line, HL-60, to Retinoic Acid (RA). HL-60 is a human myeloblastic leukemia cell-line used extensively to study human differentiation programs. Initially, we focused on the role of the BLR1 receptor in RA-induced differentiation and G1/0-arrest in HL-60. BLR1, a putative G protein-coupled receptor expressed following RA exposure, is required for RA-induced cell-cycle arrest and differentiation and causes persistent MAPK signaling. A mathematical model of RA-induced cell-cycle arrest and differentiation was formulated and tested against BLR1 wild-type (wt) knock-out and knock-in HL-60 cell-lines with and without RA. The current model described the dynamics of 729 proteins and protein complexes interconnected by 1356 interactions. An ensemble strategy was used to compensate for uncertain model parameters. The ensemble of HL-60 models recapitulated the positive feedback between BLR1 and MAPK signaling. The ensemble of models also correctly predicted Rb and p47phox regulation and the correlation between p21-CDK4-cyclin D formation and G1/0-arrest following exposure to RA. Finally, we investigated the robustness of the HL-60 network architecture to structural perturbations and generated experimentally testable hypotheses for future study. Taken together, the model presented here was a first step toward a systematic framework for analysis of programmed differentiation. These studies also demonstrated that mechanistic network modeling can help prioritize experimental directions by generating falsifiable hypotheses despite uncertainty.

  15. Gold- and silver nanoparticles affect the growth characteristics of human embryonic neural precursor cells.

    Directory of Open Access Journals (Sweden)

    Erika Söderstjerna

    Full Text Available Rapid development of nanotechnologies and their applications in clinical research have raised concerns about the adverse effects of nanoparticles (NPs on human health and environment. NPs can be directly taken up by organs exposed, but also translocated to secondary organs, such as the central nervous system (CNS after systemic- or subcutaneous administration, or via the olfactory system. The CNS is particularly vulnerable during development and recent reports describe transport of NPs across the placenta and even into brain tissue using in vitro and in vivo experimental systems. Here, we investigated whether well-characterized commercial 20 and 80 nm Au- and AgNPs have an effect on human embryonic neural precursor cell (HNPC growth. After two weeks of NP exposure, uptake of NPs, morphological features and the amount of viable and dead cells, proliferative cells (Ki67 immunostaining and apoptotic cells (TUNEL assay, respectively, were studied. We demonstrate uptake of both 20 and 80 nm Au- and AgNPs respectively, by HNPCs during proliferation. A significant effect on the sphere size- and morphology was found for all cultures exposed to Au- and AgNPs. AgNPs of both sizes caused a significant increase in numbers of proliferating and apoptotic HNPCs. In contrast, only the highest dose of 20 nm AuNPs significantly affected proliferation, whereas no effect was seen on apoptotic cell death. Our data demonstrates that both Au- and AgNPs interfere with the growth profile of HNPCs, indicating the need of further detailed studies on the adverse effects of NPs on the developing CNS.

  16. P2X7 receptors mediate innate phagocytosis by human neural precursor cells and neuroblasts.

    Science.gov (United States)

    Lovelace, Michael D; Gu, Ben J; Eamegdool, Steven S; Weible, Michael W; Wiley, James S; Allen, David G; Chan-Ling, Tailoi

    2015-02-01

    During early human neurogenesis there is overproduction of neuroblasts and neurons accompanied by widespread programmed cell death (PCD). While it is understood that CD68(+) microglia and astrocytes mediate phagocytosis during target-dependent PCD, little is known of the cell identity or the scavenger molecules used to remove apoptotic corpses during the earliest stages of human neurogenesis. Using a combination of multiple-marker immunohistochemical staining, functional blocking antibodies and antagonists, we showed that human neural precursor cells (hNPCs) and neuroblasts express functional P2X7 receptors. Furthermore, using live-cell imaging, flow cytometry, phagocytic assays, and siRNA knockdown, we showed that in a serum-free environment, doublecortin(+) (DCX) neuroblasts and hNPCs can clear apoptotic cells by innate phagocytosis mediated via P2X7. We found that both P2X7(high) DCX(low) hNPCs and P2X7(high) DCX(high) neuroblasts, derived from primary cultures of human fetal telencephalon, phagocytosed targets including latex beads, apoptotic ReNcells, and apoptotic hNPC/neuroblasts. Pretreatment of neuroblasts and hNPCs with 1 mM adenosine triphosphate (ATP), 100 µM OxATP (P2X7 antagonist), or siRNA knockdown of P2X7 inhibited phagocytosis of these targets. Our results show that P2X7 functions as a scavenger receptor under serum-free conditions resembling those in early neurogenesis. This is the first demonstration that hNPCs and neuroblasts may participate in clearance of apoptotic corpses during pre target-dependent neurogenesis and mediate phagocytosis using P2X7 as a scavenger receptor.

  17. Cyclosporin A enhances neural precursor cell survival in mice through a calcineurin-independent pathway.

    Science.gov (United States)

    Sachewsky, Nadia; Hunt, Jessica; Cooke, Michael J; Azimi, Ashkan; Zarin, Taraneh; Miu, Carween; Shoichet, Molly S; Morshead, Cindi M

    2014-08-01

    Cyclosporin A (CsA) has direct effects on neural stem and progenitor cells (together termed neural precursor cells; NPCs) in the adult central nervous system. Administration of CsA in vitro or in vivo promotes the survival of NPCs and expands the pools of NPCs in mice. Moreover, CsA administration is effective in promoting NPC activation, tissue repair and functional recovery in a mouse model of cortical stroke. The mechanism(s) by which CsA mediates this cell survival effect remains unknown. Herein, we examined both calcineurin-dependent and calcineurin-independent pathways through which CsA might mediate NPC survival. To examine calcineurin-dependent pathways, we utilized FK506 (Tacrolimus), an immunosuppressive molecule that inhibits calcineurin, as well as drugs that inhibit cyclophilin A-mediated activation of calcineurin. To evaluate the calcineurin-independent pathway, we utilized NIM811, a non-immunosuppressive CsA analog that functions independently of calcineurin by blocking mitochondrial permeability transition pore formation. We found that only NIM811 can entirely account for the pro-survival effects of CsA on NPCs. Indeed, blocking signaling pathways downstream of calcineurin activation using nNOS mice did not inhibit CsA-mediated cell survival, which supports the proposal that the effects are calcinuerin-independent. In vivo studies revealed that NIM811 administration mimics the pro-survival effects of CsA on NPCs and promotes functional recovery in a model of cortical stroke, identical to the effects seen with CsA administration. We conclude that CsA mediates its effect on NPC survival through calcineurin-independent inhibition of mitochondrial permeability transition pore formation and suggest that this pathway has potential therapeutic benefits for developing NPC-mediated cell replacement strategies. © 2014. Published by The Company of Biologists Ltd.

  18. Cell-type dependent modulation of Notch signaling by the amyloid precursor protein

    National Research Council Canada - National Science Library

    Oh, Sun Young; Chen, Ci-Di; Abraham, Carmela R

    2010-01-01

    The amyloid precursor protein is a ubiquitously expressed transmembrane protein that has been long implicated in the pathogenesis of Alzheimer's disease but its normal biological function has remained...

  19. Endothelial cell–oligodendrocyte interactions in small vessel disease and aging

    Science.gov (United States)

    Rajani, Rikesh M.

    2017-01-01

    Cerebral small vessel disease (SVD) is a prevalent, neurological disease that significantly increases the risk of stroke and dementia. The main pathological changes are vascular, in the form of lipohyalinosis and arteriosclerosis, and in the white matter (WM), in the form of WM lesions. Despite this, it is unclear to what extent the key cell types involved–the endothelial cells (ECs) of the vasculature and the oligodendrocytes of the WM–interact. Here, we describe the work that has so far been carried out suggesting an interaction between ECs and oligodendrocytes in SVD. As these interactions have been studied in more detail in other disease states and in development, we explore these systems and discuss the role these mechanisms may play in SVD. PMID:28202749

  20. Kv3.1 channels stimulate adult neural precursor cell proliferation and neuronal differentiation.

    Science.gov (United States)

    Yasuda, Takahiro; Cuny, Hartmut; Adams, David J

    2013-05-15

    Adult neural stem/precursor cells (NPCs) play a pivotal role in neuronal plasticity throughout life. Among ion channels identified in adult NPCs, voltage-gated delayed rectifier K(+) (KDR) channels are dominantly expressed. However, the KDR channel subtype and its physiological role are still undefined. We used real-time quantitative RT-PCR and gene knockdown techniques to identify a major functional KDR channel subtype in adult NPCs. Dominant mRNA expression of Kv3.1, a high voltage-gated KDR channel, was quantitatively confirmed. Kv3.1 gene knockdown with specific small interfering RNAs (siRNA) for Kv3.1 significantly inhibited Kv3.1 mRNA expression by 63.9% (P Kv3.1 is the subtype responsible for producing KDR channel outward currents. Resting membrane properties, such as resting membrane potential, of NPCs were not affected by Kv3.1 expression. Kv3.1 knockdown with 300 nm siRNA inhibited NPC growth (increase in cell numbers) by 52.9% (P Kv3.1 knockdown also significantly reduced neuronal differentiation by 31.4% (P Kv3.1 is a dominant functional KDR channel subtype expressed in adult NPCs and plays key roles in NPC proliferation and neuronal lineage commitment during differentiation.

  1. MEK Inhibitors Reverse Growth of Embryonal Brain Tumors Derived from Oligoneural Precursor Cells

    Directory of Open Access Journals (Sweden)

    Katarzyna Modzelewska

    2016-10-01

    Full Text Available Malignant brain tumors are the leading cause of cancer-related deaths in children. Primitive neuroectodermal tumors of the CNS (CNS-PNETs are particularly aggressive embryonal tumors of unknown cellular origin. Recent genomic studies have classified CNS-PNETs into molecularly distinct subgroups that promise to improve diagnosis and treatment; however, the lack of cell- or animal-based models for these subgroups prevents testing of rationally designed therapies. Here, we show that a subset of CNS-PNETs co-express oligoneural precursor cell (OPC markers OLIG2 and SOX10 with coincident activation of the RAS/MAPK (mitogen-activated protein kinase pathway. Modeling NRAS activation in embryonic OPCs generated malignant brain tumors in zebrafish that closely mimic the human oligoneural/NB-FOXR2 CNS-PNET subgroup by histology and comparative oncogenomics. The zebrafish CNS-PNET model was used to show that MEK inhibitors selectively eliminate Olig2+/Sox10+ CNS-PNET tumors in vivo without impacting normal brain development. Thus, MEK inhibitors represent a promising rationally designed therapy for children afflicted with oligoneural/NB-FOXR2 CNS-PNETs.

  2. Lead exposure in pheochromocytoma cells induces persistent changes in amyloid precursor protein gene methylation patterns.

    Science.gov (United States)

    Li, Yuan-Yuan; Chen, Tian; Wan, Yanjian; Xu, Shun-qing

    2012-08-01

    It has been suggested that lead (Pb) exposure in early life may increase amyloid precursor protein (APP) expression and promote the pathogenesis of Alzheimer's disease in old age. The current study examined whether the DNA methylation patterns of APP gene in rat pheochromocytoma (PC12) cells changed after Pb acetate exposure. Undifferentiated PC12 cells were exposed to three doses of Pb acetate (50, 250, and 500 nM) and one control for 2 days or 1 week. The methylation patterns of APP promoter and global DNA methylation were analyzed. The DNA methyltransferase 1 (DNMT1) expression and the level of amyloid β peptide (Aβ) were also investigated. The results showed that the exposure of the three concentrations of Pb acetate could make the APP promoter hypomethylated. The global DNA methylation level and the expression of DNMT1 were changed in the 500 nM group after 2 days exposure and in the 250 and 500 nM group after 7 days exposure. Thus, Pb may exert neurotoxic effects through mechanisms that alter the global and promoter methylation patterns of APP gene. © 2010 Wiley Periodicals, Inc. Environ Toxicol, 2012. Copyright © 2010 Wiley Periodicals, Inc.

  3. In vitro cultured progenitors and precursors of cardiac cell lineages from human normal and post-ischemic hearts

    Directory of Open Access Journals (Sweden)

    F Di Meglio

    2009-08-01

    Full Text Available The demonstration of the presence of dividing primitive cells in damaged hearts has sparked increased interest about myocardium regenerative processes. We examined the rate and the differentiation of in vitro cultured resident cardiac primitive cells obtained from pathological and normal human hearts in order to evaluate the activation of progenitors and precursors of cardiac cell lineages in post-ischemic human hearts. The precursors and progenitors of cardiomyocyte, smooth muscle and endothelial lineage were identified by immunocytochemistry and the expression of characteristic markers was studied by western blot and RT-PCR. The amount of proteins characteristic for cardiac cells (a-SA and MHC, VEGFR-2 and FVIII, SMA for the precursors of cardiomyocytes, endothelial and smooth muscle cells, respectively inclines toward an increase in both a-SA and MHC. The increased levels of FVIII and VEGFR2 are statistically significant, suggesting an important re-activation of neoangiogenesis. At the same time, the augmented expression of mRNA for Nkx 2.5, the trascriptional factor for cardiomyocyte differentiation, confirms the persistence of differentiative processes in terminally injured hearts. Our study would appear to confirm the activation of human heart regeneration potential in pathological conditions and the ability of its primitive cells to maintain their proliferative capability in vitro. The cardiac cell isolation method we used could be useful in the future for studying modifications to the microenvironment that positively influence cardiac primitive cell differentiation or inhibit, or retard, the pathological remodeling and functional degradation of the heart.

  4. CD73 protein as a source of extracellular precursors for sustained NAD+ biosynthesis in FK866-treated tumor cells.

    Science.gov (United States)

    Grozio, Alessia; Sociali, Giovanna; Sturla, Laura; Caffa, Irene; Soncini, Debora; Salis, Annalisa; Raffaelli, Nadia; De Flora, Antonio; Nencioni, Alessio; Bruzzone, Santina

    2013-09-06

    NAD(+) is mainly synthesized in human cells via the "salvage" pathways starting from nicotinamide, nicotinic acid, or nicotinamide riboside (NR). The inhibition with FK866 of the enzyme nicotinamide phosphoribosyltransferase (NAMPT), catalyzing the first reaction in the "salvage" pathway from nicotinamide, showed potent antitumor activity in several preclinical models of solid and hematologic cancers. In the clinical studies performed with FK866, however, no tumor remission was observed. Here we demonstrate that low micromolar concentrations of extracellular NAD(+) or NAD(+) precursors, nicotinamide mononucleotide (NMN) and NR, can reverse the FK866-induced cell death, this representing a plausible explanation for the failure of NAMPT inhibition as an anti-cancer therapy. NMN is a substrate of both ectoenzymes CD38 and CD73, with generation of NAM and NR, respectively. In this study, we investigated the roles of CD38 and CD73 in providing ectocellular NAD(+) precursors for NAD(+) biosynthesis and in modulating cell susceptibility to FK866. By specifically silencing or overexpressing CD38 and CD73, we demonstrated that endogenous CD73 enables, whereas CD38 impairs, the conversion of extracellular NMN to NR as a precursor for intracellular NAD(+) biosynthesis in human cells. Moreover, cell viability in FK866-treated cells supplemented with extracellular NMN was strongly reduced in tumor cells, upon pharmacological inhibition or specific down-regulation of CD73. Thus, our study suggests that genetic or pharmacologic interventions interfering with CD73 activity may prove useful to increase cancer cell sensitivity to NAMPT inhibitors.

  5. Photoreceptor precursors derived from three-dimensional embryonic stem cell cultures integrate and mature within adult degenerate retina.

    Science.gov (United States)

    Gonzalez-Cordero, Anai; West, Emma L; Pearson, Rachael A; Duran, Yanai; Carvalho, Livia S; Chu, Colin J; Naeem, Arifa; Blackford, Samuel J I; Georgiadis, Anastasios; Lakowski, Jorn; Hubank, Mike; Smith, Alexander J; Bainbridge, James W B; Sowden, Jane C; Ali, Robin R

    2013-08-01

    Irreversible blindness caused by loss of photoreceptors may be amenable to cell therapy. We previously demonstrated retinal repair and restoration of vision through transplantation of photoreceptor precursors obtained from postnatal retinas into visually impaired adult mice. Considerable progress has been made in differentiating embryonic stem cells (ESCs) in vitro toward photoreceptor lineages. However, the capability of ESC-derived photoreceptors to integrate after transplantation has not been demonstrated unequivocally. Here, to isolate photoreceptor precursors fit for transplantation, we adapted a recently reported three-dimensional (3D) differentiation protocol that generates neuroretina from mouse ESCs. We show that rod precursors derived by this protocol and selected via a GFP reporter under the control of a Rhodopsin promoter integrate within degenerate retinas of adult mice and mature into outer segment-bearing photoreceptors. Notably, ESC-derived precursors at a developmental stage similar to postnatal days 4-8 integrate more efficiently compared with cells at other stages. This study shows conclusively that ESCs can provide a source of photoreceptors for retinal cell transplantation.

  6. Investigation of optical spacer layers from solution based precursors for polymer solar cells using X-ray reflectometry

    DEFF Research Database (Denmark)

    Andersen, Philip Hvidthøft Delff; Skårhøj, Jakob; Andreasen, Jens Wenzel

    2009-01-01

    Optical spacer layers based on titaniumalkoxide precursor solutions were prepared by spin-coating on top of bulk heterojunction layers based on poly-3-hexylthiophene (P3HT) and phenyl-C61-butyric acid methylester (PCBM). Models and experiment have shown that the performance of polymer solar cells...

  7. Amyloid precursor protein (APP) affects global protein synthesis in dividing human cells.

    Science.gov (United States)

    Sobol, Anna; Galluzzo, Paola; Liang, Shuang; Rambo, Brittany; Skucha, Sylvia; Weber, Megan J; Alani, Sara; Bocchetta, Maurizio

    2015-05-01

    Hypoxic non-small cell lung cancer (NSCLC) is dependent on Notch-1 signaling for survival. Targeting Notch-1 by means of γ-secretase inhibitors (GSI) proved effective in killing hypoxic NSCLC. Post-mortem analysis of GSI-treated, NSCLC-burdened mice suggested enhanced phosphorylation of 4E-BP1 at threonines 37/46 in hypoxic tumor tissues. In vitro dissection of this phenomenon revealed that Amyloid Precursor Protein (APP) inhibition was responsible for a non-canonical 4E-BP1 phosphorylation pattern rearrangement-a process, in part, mediated by APP regulation of the pseudophosphatase Styx. Upon APP depletion we observed modifications of eIF-4F composition indicating increased recruitment of eIF-4A to the mRNA cap. This phenomenon was supported by the observation that cells with depleted APP were partially resistant to silvestrol, an antibiotic that interferes with eIF-4A assembly into eIF-4F complexes. APP downregulation in dividing human cells increased the rate of global protein synthesis, both cap- and IRES-dependent. Such an increase seemed independent of mTOR inhibition. After administration of Torin-1, APP downregulation and Mechanistic Target of Rapamycin Complex 1 (mTORC-1) inhibition affected 4E-BP1 phosphorylation and global protein synthesis in opposite fashions. Additional investigations indicated that APP operates independently of mTORC-1. Key phenomena described in this study were reversed by overexpression of the APP C-terminal domain. The presented data suggest that APP may be a novel regulator of protein synthesis in dividing human cells, both cancerous and primary. Furthermore, APP appears to affect translation initiation using mechanisms seemingly dissimilar to mTORC-1 regulation of cap-dependent protein synthesis.

  8. Herpes Simplex Virus Dances with Amyloid Precursor Protein while Exiting the Cell

    Science.gov (United States)

    Cheng, Shi-Bin; Ferland, Paulette; Webster, Paul; Bearer, Elaine L.

    2011-01-01

    Herpes simplex type 1 (HSV1) replicates in epithelial cells and secondarily enters local sensory neuronal processes, traveling retrograde to the neuronal nucleus to enter latency. Upon reawakening newly synthesized viral particles travel anterograde back to the epithelial cells of the lip, causing the recurrent cold sore. HSV1 co-purifies with amyloid precursor protein (APP), a cellular transmembrane glycoprotein and receptor for anterograde transport machinery that when proteolyzed produces A-beta, the major component of senile plaques. Here we focus on transport inside epithelial cells of newly synthesized virus during its transit to the cell surface. We hypothesize that HSV1 recruits cellular APP during transport. We explore this with quantitative immuno-fluorescence, immuno-gold electron-microscopy and live cell confocal imaging. After synchronous infection most nascent VP26-GFP-labeled viral particles in the cytoplasm co-localize with APP (72.8+/−6.7%) and travel together with APP inside living cells (81.1+/−28.9%). This interaction has functional consequences: HSV1 infection decreases the average velocity of APP particles (from 1.1+/−0.2 to 0.3+/−0.1 µm/s) and results in APP mal-distribution in infected cells, while interplay with APP-particles increases the frequency (from 10% to 81% motile) and velocity (from 0.3+/−0.1 to 0.4+/−0.1 µm/s) of VP26-GFP transport. In cells infected with HSV1 lacking the viral Fc receptor, gE, an envelope glycoprotein also involved in viral axonal transport, APP-capsid interactions are preserved while the distribution and dynamics of dual-label particles differ from wild-type by both immuno-fluorescence and live imaging. Knock-down of APP with siRNA eliminates APP staining, confirming specificity. Our results indicate that most intracellular HSV1 particles undergo frequent dynamic interplay with APP in a manner that facilitates viral transport and interferes with normal APP transport and distribution. Such dynamic

  9. 脑源性神经营养因子前体在脊髓损伤后对少突胶质细胞存活及生长的影响%Effects of precursor of brain-derived neurotrophic factor on the survival and growth of oligodendrocytes after spinal cord injury

    Institute of Scientific and Technical Information of China (English)

    刘燊; 冯世庆; 周先虎; 宁广智; 张超

    2013-01-01

    Objective To investigate whether the precursor of Brain-drived neurotrophic factor (proBDNF) can be expressed on oligodenerocyte precursor cells (OPCs) and the effects of proBDNF on the survival and growth of OPCs in the acute period of spinal cord injury (SCI).Methods Primary cuhure of OPCs from neonatal C57BL/6 mice was applied for the studies.Western blotting was used to investigate the expression levels of proBDNF and its receptors p75NTR and sortilin in OPCs.100 μg/L bovine serum albumin (BSA) was used as a control group and gradient concentrations of proBDNF (1,10,100 μg/L) were used to treat the cells.Each group had 6 wells of cultured cells.After the treatment,crystal violet staining and β-tublin immunofluorescence staining were used to observe the size and growth of cells.Results Western blotting showed that proBDNF,p75NTR and sortilin were endogeneously expressed on OPCs.As compared with the BSA control,proBDNF inhibited survival of OPCs (537.67 ± 34.93 vs.440.67 ± 9.29,390.67 ± 9.45 and 337.25 ± 7.27) and the difference was statistically significant (P < 0.001).Meanwhile,proBDNF also inhibited the OPCs growth as compared with BSA group.The OPCs in proBDNF treated groups had less long projections and smaller size [(2.44 ± 0.71) vs.(1.65 ± 0.10),(1.30 ± 0.11) and (0.95 ± 0.08) μm2].The difference was statistically significant (P < 0.05 in 1 μg/L proBDNF group,and P < 0.01 in other groups).Conclusion OPCs express proBDNF and its receptors endogenously.proBDNF can inhibit the survival and growth of OPCs and the inhibitory effects may be induced by p75NTR-sortilin pathway.%目的 观察脑源性神经生长因子前体(proBDNF)在少突胶质细胞前体细胞(OPCs)的表达及其对OPCs存活及生长的调控作用.方法 取新生C57BL/6小鼠大脑皮层分离少突胶质细胞前体细胞,体外原代培养.应用Western blot法观察proBDNF及其受体p75NTR和sortilin在OPCs内的表达水平;设置100 μg/L胎牛血清白蛋白(BSA

  10. Inhibition of beta-site amyloid precursor protein-cleaving enzyme and beta-amyloid precursor protein genes in SK-N-SH cells

    Institute of Scientific and Technical Information of China (English)

    Suqin Gao; Lin Sun; Enji Han; Hongshun Qi; Jinbo Feng; Shunliang Xu; Wen Xia

    2009-01-01

    BACKGROUND:Previous studies have demonstrated that Piper futokadsura stem selectively inhibits expression of amyloid precursor protein (APP) at the mRNA level.In addition,the piperlonguminine (A) and dihydropiperlonguminine (B) components (1:0.8),which can be separated from Futokadsura stem,selectively inhibit expression of the APP at mRNA and protein levels.OBJECTIVE:Based on previous findings,the present study investigated the effects of β-site amyloid precursor protein cleaving enzyme (BACE1) and APP genes on the production of β-amyloid peptide 42 (Aβ42) in human neuroblastoma cells (SK-N-SH cells) using small interfering RNAs (siRNAs) and A/B components separated from Futokadsura stem,respectively.DESIGN,TIME AND SETTING:A gene interference-based randomized,controlled,in vitro experiment was performed at the Key Laboratory of Cardiovascular Remodeling and Function Research,Ministries of Education and Public Health,and Institute of Pharmacologic Research,School of Pharmaceutical Science & Department of Biochemistry,School of Medicine,Shandong University between July 2006 and December 2007.MATERIALS:SK-N-SH cells were provided by Shanghai Institutes of Biological Sciences,Chinese Academy of Sciences,Shanghai,China;mouse anti-human BACE1 monoclonal antibody was purchased from R&D Systems,USA;mouse anti-human APP monoclonal antibody was purchased from Cell Signaling Technology,USA;and horseradish peroxidase (HRP)-conjugated goat anti-mouse IgG was provided by Sigma,USA.METHODS:The human BACE1 cDNA sequence was obtained from NCBI website (www.ncbi.nlm.nih.gov/sites/entrez).Three pairs of siRNAs,specific to human BACE1 gene,were synthesized through the use of Silencer? pre-designed siRNA specification,and were transfected into SK-N-SH cells with siPORT NeoFX transfection agent to compare the effects of different concentrations of siRNAs (10-50 nmol/L) on SK-N-SH cells.Futokadsura stem was separated and purified with chemical methods,and the crystal was composed of

  11. Low density lipoprotein receptor-related protein-2/megalin is expressed in oligodendrocytes in the mouse spinal cord white matter

    DEFF Research Database (Denmark)

    Wicher, Grzegorz; Larsson, Mårten; Svenningsen, Åsa Fex

    2006-01-01

    Lipoprotein receptor-related protein-2 (LRP2)/megalin is a member of the low density lipoprotein receptor (LDLR) family, and is essential in absorptive epithelia for endocytosis of lipoproteins, low molecular weight proteins, cholesterol and vitamins, as well as in cellular signaling. Previous st...... that spinal cord oligodendrocytes are phenotypically different from those in the brain, and indicate that megalin translocates signals from the cell membrane to the nucleus of oligodendrocytes during the formation and maintenance of myelin of long spinal cord pathways....

  12. OPIOID PRECURSOR PROTEIN ISOFORM IS TARGETED TO THE CELL NUCLEI IN THE HUMAN BRAIN

    DEFF Research Database (Denmark)

    Kononenko, Olga; Bazov, Igor; Watanabe, Hiroyuki;

    2016-01-01

    Neuropeptide precursors are traditionally viewed as proteins giving rise to small neuropeptide molecules. Prodynorphin (PDYN) is the precursor protein to dynorphins, endogenous ligands for the κ-opioid receptor. We here describe two novel splicing variants of human PDYN mRNA. Expression of one...

  13. Epigenetic mechanisms facilitating oligodendrocyte development, maturation, and aging.

    Science.gov (United States)

    Copray, Sjef; Huynh, Jimmy Long; Sher, Falak; Casaccia-Bonnefil, Patrizia; Boddeke, Erik

    2009-11-15

    The process of oligodendrocyte differentiation is regulated by a dynamic interaction between a genetic and an epigenetic program. Recent studies, addressing nucleosomal histone modifications have considerably increased our knowledge regarding epigenetic regulation of gene expression during oligodendrocyte development and aging. These results have generated new hypotheses regarding the mechanisms underlying the decreased efficiency of endogenous remyelination in response to demyelinating injuries with increasing age. In this review, we present an overview of the epigenetic mechanisms regulating gene expression at specific stages of oligodendrocyte differentiation and maturation as well as the changes that occur with aging.

  14. Nestin- and Doublecortin-Positive Cells Reside in Adult Spinal Cord Meninges and Participate in Injury-Induced Parenchymal Reaction

    OpenAIRE

    2011-01-01

    Adult spinal cord has little regenerative potential, thus limiting patient recovery following injury. In this study, we describe a new population of cells resident in the adult rat spinal cord meninges that express the neural stem/precursor markers nestin and doublecortin. Furthermore, from dissociated meningeal tissue a neural stem cell population was cultured in vitro and subsequently shown to differentiate into functional neurons or mature oligodendrocytes. Proliferation rate and number of...

  15. Neuroglial cells in long-term primary cultures from the gilthead sea bream (Sparus aurata L.: new functional in vitro model from bony fish brain

    Directory of Open Access Journals (Sweden)

    Gerardo Centoducati

    2013-01-01

    Full Text Available Neuroglia has been historically considered the “glue” of the nervous system, as the ancient Greek name suggests, being simply referred as non-neuronal cells, with supporting functions for neurons in the CNS of mammalian and lower vertebrates. All around the world, approximately 283 cell lines were obtained from fish, yet none of these was from the brain of Sparus aurata, neither in cell lines nor as primary culture. Here we describe a novel in vitro reproducible neuroglial marine model for establishing primary neuroglial cell cultures, by dissociating the whole brain of seabream juveniles. We showed that proliferating neural stem cells produced alongside three generating lineages, such as neuronal precursor cells, astroglial precursor cells and oligodendroglia precursor cells, which developed respectively neurons, astrocytes and oligodendrocytes. The radial glia, finely described by morphological studies and immunochemical antigen expression, showed a peculiar spatial distribution, giving rise simultaneously both to astrocytes and neuronal precursors within a highly proliferative assemblate. Radial glia cells were assessed by glial fibrillary acidic protein (GFAP and vimentin reactivity, astrocytes by GFAP, neurons by the neuron-specific markers for ubiquitin carboxy-terminal hydrolase 1 (UCHL1 and intermediate filament associated protein (NF, whereas myelinating oligodendrocytes were immunostained with anti-myelin basic protein (MBP and anti-O4. Our findings suggest that seabream neuroglial cells gain in 3-4 weeks of culturing proliferation, neuroglial differentiation, and oligodendrocyte maturation with myelination, thus disclosing on the possibility that mixed neuroglial cultures can accelerate the maturation of oligodendrocytes and the regeneration of CNS injury in fish.

  16. Combined transplantation of neural precursor cells and olfactory ensheathing cells for the treatment of X-linked adrenoleukodystrophy in children

    Directory of Open Access Journals (Sweden)

    Yang H

    2017-04-01

    Full Text Available Hui Yang,1,* Yu Zhang,1,* Zhaoyan Wang,1 Wei Lu,1 Fang Liu,1 Xin Yu,2 Xiaoyan Zheng,1 Yinxiang Yang,1 Zuo Luan,1 Suqing Qu1 1Department of Pediatrics, 2Department of Neurological Surgery, Navy General Hospital, Beijing, People’s Republic of China *These authors contributed equally to this work. Abstract: Hematopoietic stem cell transplantation is only suitable for early-stage adrenoleukodystrophy (ALD. In this study, we observed the therapeutic efficacy of combined transplantation of neural precursor cells (NPCs and olfactory ensheathing cells (OECs on late-stage X-linked ALD in nine children who were admitted in our hospital between June 2009 and January 2014. Related patient information included onset time 3 months to 1 year, magnetic resonance imaging (MRI score 11.02±0.90, and neurologic function score 2–3. All patients received combined transplantation of NPCs and OECs by injection around the lateral angle of the frontotemporal–occipital lesion under MRI guidance. It was found that the visual function, sleep, and communication obstacles were improved significantly without evidence of disease progression in six (66.7% of the nine patients within 1 month after transplantation. In two of the six patients, the lesions became significantly smaller than before, although their MRI scores remained unchanged significantly. In addition, cell therapy did not induce any irreversible adverse event during the study period, indicating that combined transplantation of NPCs and OECs was safe and reliable, and could improve the clinical manifestations of ALD in children within a short time. Although this cell therapy was not able to halt the progression of the disease 1–3 months after transplantation, it could still be used as an early treatment and provide patients with more opportunities for hematopoietic stem cell transplantation, which is the only effective long-term treatment for X-linked ALD at present. The preliminary results from this study

  17. Oligodendrocyte lineage and subventricular zone response to traumatic axonal injury in the corpus callosum.

    Science.gov (United States)

    Sullivan, Genevieve M; Mierzwa, Amanda J; Kijpaisalratana, Naruchorn; Tang, Haiying; Wang, Yong; Song, Sheng-Kwei; Selwyn, Reed; Armstrong, Regina C

    2013-12-01

    Traumatic brain injury frequently causes traumatic axonal injury (TAI) in white matter tracts. Experimental TAI in the corpus callosum of adult mice was used to examine the effects on oligodendrocyte lineage cells and myelin in conjunction with neuroimaging. The injury targeted the corpus callosum over the subventricular zone, a source of neural stem/progenitor cells. Traumatic axonal injury was produced in the rostral body of the corpus callosum by impact onto the skull at the bregma. During the first week after injury, magnetic resonance diffusion tensor imaging showed that axial diffusivity decreased in the corpus callosum and that corresponding regions exhibited significant axon damage accompanied by hypertrophic microglia and reactive astrocytes. Oligodendrocyte progenitor proliferation increased in the subventricular zone and corpus callosum. Oligodendrocytes in the corpus callosum shifted toward upregulation of myelin gene transcription. Plp/CreER(T):R26IAP reporter mice showed normal reporter labeling of myelin sheaths 0 to 2 days after injury but labeling was increased between 2 and 7 days after injury. Electron microscopy revealed axon degeneration, demyelination, and redundant myelin figures. These findings expand the cell types and responses to white matter injuries that inform diffusion tensor imaging evaluation and identify pivotal white matter changes after TAI that may affect axon vulnerability vs. recovery after brain injury.

  18. Ago2 immunoprecipitation identifies predicted microRNAs in human embryonic stem cells and neural precursors.

    Directory of Open Access Journals (Sweden)

    Loyal A Goff

    Full Text Available BACKGROUND: MicroRNAs are required for maintenance of pluripotency as well as differentiation, but since more microRNAs have been computationally predicted in genome than have been found, there are likely to be undiscovered microRNAs expressed early in stem cell differentiation. METHODOLOGY/PRINCIPAL FINDINGS: SOLiD ultra-deep sequencing identified >10(7 unique small RNAs from human embryonic stem cells (hESC and neural-restricted precursors that were fit to a model of microRNA biogenesis to computationally predict 818 new microRNA genes. These predicted genomic loci are associated with chromatin patterns of modified histones that are predictive of regulated gene expression. 146 of the predicted microRNAs were enriched in Ago2-containing complexes along with 609 known microRNAs, demonstrating association with a functional RISC complex. This Ago2 IP-selected subset was consistently expressed in four independent hESC lines and exhibited complex patterns of regulation over development similar to previously-known microRNAs, including pluripotency-specific expression in both hESC and iPS cells. More than 30% of the Ago2 IP-enriched predicted microRNAs are new members of existing families since they share seed sequences with known microRNAs. CONCLUSIONS/SIGNIFICANCE: Extending the classic definition of microRNAs, this large number of new microRNA genes, the majority of which are less conserved than their canonical counterparts, likely represent evolutionarily recent regulators of early differentiation. The enrichment in Ago2 containing complexes, the presence of chromatin marks indicative of regulated gene expression, and differential expression over development all support the identification of 146 new microRNAs active during early hESC differentiation.

  19. Hematopoietic reconstitution by multipotent adult progenitor cells: precursors to long-term hematopoietic stem cells

    Science.gov (United States)

    Serafini, Marta; Dylla, Scott J.; Oki, Masayuki; Heremans, Yves; Tolar, Jakub; Jiang, Yuehua; Buckley, Shannon M.; Pelacho, Beatriz; Burns, Terry C.; Frommer, Sarah; Rossi, Derrick J.; Bryder, David; Panoskaltsis-Mortari, Angela; O'Shaughnessy, Matthew J.; Nelson-Holte, Molly; Fine, Gabriel C.; Weissman, Irving L.; Blazar, Bruce R.; Verfaillie, Catherine M.

    2007-01-01

    For decades, in vitro expansion of transplantable hematopoietic stem cells (HSCs) has been an elusive goal. Here, we demonstrate that multipotent adult progenitor cells (MAPCs), isolated from green fluorescent protein (GFP)-transgenic mice and expanded in vitro for >40–80 population doublings, are capable of multilineage hematopoietic engraftment of immunodeficient mice. Among MAPC-derived GFP+CD45.2+ cells in the bone marrow of engrafted mice, HSCs were present that could radioprotect and reconstitute multilineage hematopoiesis in secondary and tertiary recipients, as well as myeloid and lymphoid hematopoietic progenitor subsets and functional GFP+ MAPC-derived lymphocytes that were functional. Although hematopoietic contribution by MAPCs was comparable to control KTLS HSCs, approximately 103-fold more MAPCs were required for efficient engraftment. Because GFP+ host-derived CD45.1+ cells were not observed, fusion is not likely to account for the generation of HSCs by MAPCs. PMID:17227908

  20. Pathways and subcellular compartmentation of NAD biosynthesis in human cells: from entry of extracellular precursors to mitochondrial NAD generation.

    Science.gov (United States)

    Nikiforov, Andrey; Dölle, Christian; Niere, Marc; Ziegler, Mathias

    2011-06-17

    NAD is a vital redox carrier, and its degradation is a key element of important regulatory pathways. NAD-mediated functions are compartmentalized and have to be fueled by specific biosynthetic routes. However, little is known about the different pathways, their subcellular distribution, and regulation in human cells. In particular, the route(s) to generate mitochondrial NAD, the largest subcellular pool, is still unknown. To visualize organellar NAD changes in cells, we targeted poly(ADP-ribose) polymerase activity into the mitochondrial matrix. This activity synthesized immunodetectable poly(ADP-ribose) depending on mitochondrial NAD availability. Based on this novel detector system, detailed subcellular enzyme localizations, and pharmacological inhibitors, we identified extracellular NAD precursors, their cytosolic conversions, and the pathway of mitochondrial NAD generation. Our results demonstrate that, besides nicotinamide and nicotinic acid, only the corresponding nucleosides readily enter the cells. Nucleotides (e.g. NAD and NMN) undergo extracellular degradation resulting in the formation of permeable precursors. These precursors can all be converted to cytosolic and mitochondrial NAD. For mitochondrial NAD synthesis, precursors are converted to NMN in the cytosol. When taken up into the organelles, NMN (together with ATP) serves as substrate of NMNAT3 to form NAD. NMNAT3 was conclusively localized to the mitochondrial matrix and is the only known enzyme of NAD synthesis residing within these organelles. We thus present a comprehensive dissection of mammalian NAD biosynthesis, the groundwork to understand regulation of NAD-mediated processes, and the organismal homeostasis of this fundamental molecule.

  1. Electrochemical studies on the CZT precursor deposition for CZTS solar cell application

    Science.gov (United States)

    Jin, Hyunsoo; Park, Chansu; Park, Yoosei; Kim, Yangdo; Park, Sungkyun; Choi, Jongchan; Lee, Jae-Ho

    2016-11-01

    Cu-Zn-Sn-(Se,S)(CZTS) is one of the most promising thin-film solar cells. The electrochemical methods to fabricate CZT deposits from one bath were investigated. Citrate was used to form a complex with each metallic compound. The proper potential and pH were determined from cyclic voltammetry and stability diagrams, respectively. The selected range of pH was from 4.7 to 6.2, and that of the voltage was from -0.85 V to -1.15 V (vs. Ag/AgCl). The theoretical value of the Cu/(Zn+Sn) ratio should be between 0.7 and 1.0 to shows proper photovoltaic effect. The working condition to produce such a ratio were -0.85 V at pH 4.7 and -1.15 V at pH 5.7 based on an energy dispersive spectrometer analysis of the deposits. Deposits at -1.15 V and pH 5.7 were denser than those at -0.85 V and pH 4.7. Finally, -1.15 V and pH 5.7 was selected optimum condition for the electrodeposition of the CZT precursor.

  2. Oxidative stress affects processing of amyloid precursor protein in vascular endothelial cells.

    Science.gov (United States)

    Muche, Abebe; Arendt, Thomas; Schliebs, Reinhard

    2017-01-01

    Oxidative stress is thought to be a key player in the pathogenesis of neurodegenerative dementia, including Alzheimer's disease (AD). It has been assumed that oxidative stress contributes to the ß-amyloid deposition in cerebral blood vessels. In order to prove this hypothesis, we examined the effect of oxidative stress on the processing of amyloid precursor protein (APP) in primary endothelial cells (EC) derived from cerebral cortical tissue of transgenic Tg2576 mice. Following exposure of EC by 1 μM hydrogen peroxide for up to 48 hours, formation and secretion of APP cleavage products sAPPα and sAPPß into the culture medium as well as the expression of endothelial APP were assessed. Oxidative stress resulted in enhanced secretion of sAPPß into the culture medium as compared to controls (absence of hydrogen peroxide), which was accompanied by an increased APP expression, induction of VEGF synthesis, nitric oxide and oxygen free radicals productions, and differential changes of endothelial phospo-p42/44 MAPK expression. The data suggest that oxidative stress may represent a major risk factor in causing Aß deposition in the brain vascular system by initiating the amyloidogenic route of endothelial APP processing. The enhanced β-secretase activity following oxidative stress exposure, possibly promoted by phosphorylation of p42/44 MAPK.

  3. Identification of FtsW as a transporter of lipid-linked cell wall precursors across the membrane

    Science.gov (United States)

    Mohammadi, Tamimount; van Dam, Vincent; Sijbrandi, Robert; Vernet, Thierry; Zapun, André; Bouhss, Ahmed; Diepeveen-de Bruin, Marlies; Nguyen-Distèche, Martine; de Kruijff, Ben; Breukink, Eefjan

    2011-01-01

    Bacterial cell growth necessitates synthesis of peptidoglycan. Assembly of this major constituent of the bacterial cell wall is a multistep process starting in the cytoplasm and ending in the exterior cell surface. The intracellular part of the pathway results in the production of the membrane-anchored cell wall precursor, Lipid II. After synthesis this lipid intermediate is translocated across the cell membrane. The translocation (flipping) step of Lipid II was demonstrated to require a specific protein (flippase). Here, we show that the integral membrane protein FtsW, an essential protein of the bacterial division machinery, is a transporter of the lipid-linked peptidoglycan precursors across the cytoplasmic membrane. Using Escherichia coli membrane vesicles we found that transport of Lipid II requires the presence of FtsW, and purified FtsW induced the transbilayer movement of Lipid II in model membranes. This study provides the first biochemical evidence for the involvement of an essential protein in the transport of lipid-linked cell wall precursors across biogenic membranes. PMID:21386816

  4. Isolation of Mature (Peritoneum-Derived Mast Cells and Immature (Bone Marrow-Derived Mast Cell Precursors from Mice.

    Directory of Open Access Journals (Sweden)

    Steffen K Meurer

    Full Text Available Mast cells (MCs are a versatile cell type playing key roles in tissue morphogenesis and host defence against bacteria and parasites. Furthermore, they can enhance immunological danger signals and are implicated in inflammatory disorders like fibrosis. This granulated cell type originates from the myeloid lineage and has similarities to basophilic granulocytes, both containing large quantities of histamine and heparin. Immature murine mast cells mature in their destination tissue and adopt either the connective tissue (CTMC or mucosal (MMC type. Some effector functions are executed by activation/degranulation of MCs which lead to secretion of a typical set of MC proteases (MCPT and of the preformed or newly synthesized mediators from its granules into the local microenvironment. Due to the potential accumulation of mutations in key signalling pathway components of corresponding MC cell-lines, primary cultured MCs are an attractive mean to study general features of MC biology and aspects of MC functions relevant to human disease. Here, we describe a simple protocol for the simultaneous isolation of mature CTMC-like murine MCs from the peritoneum (PMCs and immature MC precursors from the bone marrow (BM. The latter are differentiated in vitro to yield BM-derived MCs (BMMC. These cells display the typical morphological and phenotypic features of MCs, express the typical MC surface markers, and can be propagated and kept in culture for several weeks. The provided protocol allows simple amplification of large quantities of homogenous, non-transformed MCs from the peritoneum and bone marrow-derived mast cells for cell- and tissue-based biomedical research.

  5. Comparison of microglia and infiltrating CD11c+ cells as antigen presenting cells for T cell proliferation and cytokine response

    DEFF Research Database (Denmark)

    Wlodarczyk, Agnieszka; Løbner, Morten; Cédile, Oriane

    2014-01-01

    BACKGROUND: Tissue-resident antigen-presenting cells (APC) exert a major influence on the local immune environment. Microglia are resident myeloid cells in the central nervous system (CNS), deriving from early post-embryonic precursors, distinct from adult hematopoietic lineages. Dendritic cells...... but detectable levels of all these cytokines. Transforming growth factor beta expression was similar in all three populations. Although CNS-resident and blood-derived CD11c+ cells showed equivalent ability to induce proliferation of myelin oligodendrocyte glycoprotein-immunised CD4+ T cells, CD11c+ microglia...

  6. Myogenic Precursors from iPS Cells for Skeletal Muscle Cell Replacement Therapy

    Directory of Open Access Journals (Sweden)

    Isart Roca

    2015-01-01

    Full Text Available The use of adult myogenic stem cells as a cell therapy for skeletal muscle regeneration has been attempted for decades, with only moderate success. Myogenic progenitors (MP made from induced pluripotent stem cells (iPSCs are promising candidates for stem cell therapy to regenerate skeletal muscle since they allow allogenic transplantation, can be produced in large quantities, and, as compared to adult myoblasts, present more embryonic-like features and more proliferative capacity in vitro, which indicates a potential for more self-renewal and regenerative capacity in vivo. Different approaches have been described to make myogenic progenitors either by gene overexpression or by directed differentiation through culture conditions, and several myopathies have already been modeled using iPSC-MP. However, even though results in animal models have shown improvement from previous work with isolated adult myoblasts, major challenges regarding host response have to be addressed and clinically relevant transplantation protocols are lacking. Despite these challenges we are closer than we think to bringing iPSC-MP towards clinical use for treating human muscle disease and sporting injuries.

  7. An injectable hydrogel incorporating mesenchymal precursor cells and pentosan polysulphate for intervertebral disc regeneration.

    Science.gov (United States)

    Frith, Jessica E; Cameron, Andrew R; Menzies, Donna J; Ghosh, Peter; Whitehead, Darryl L; Gronthos, Stan; Zannettino, Andrew C W; Cooper-White, Justin J

    2013-12-01

    Intervertebral disc (IVD) degeneration is one of the leading causes of lower back pain and a major health problem worldwide. Current surgical treatments include excision or immobilisation, with neither approach resulting in the repair of the degenerative disc. As such, a tissue engineering-based approach in which stem cells, coupled with an advanced delivery system, could overcome this deficiency and lead to a therapy that encourages functional fibrocartilage generation in the IVD. In this study, we have developed an injectable hydrogel system based on enzymatically-crosslinked polyethylene glycol and hyaluronic acid. We examined the effects of adding pentosan polysulphate (PPS), a synthetic glycosaminoglycan-like factor that has previously been shown (in vitro and in vivo) to this gel system in order to induce chondrogenesis in mesenchymal precursor cells (MPCs) when added as a soluble factor, even in the absence of additional growth factors such as TGF-β. We show that both the gelation rate and mechanical strength of the resulting hydrogels can be tuned in order to optimise the conditions required to produce gels with the desired combination of properties for an IVD scaffold. Human immunoselected STRO-1+ MPCs were then incorporated into the hydrogels. They were shown to retain good viability after both the initial formation of the gel and for longer-term culture periods in vitro. Furthermore, MPC/hydrogel composites formed cartilage-like tissue which was significantly enhanced by the incorporation of PPS into the hydrogels, particularly with respect to the deposition of type-II-collagen. Finally, using a wild-type rat subcutaneous implantation model, we examined the extent of any immune reaction and confirmed that this matrix is well tolerated by the host. Together these data provide evidence that such a system has significant potential as both a delivery vehicle for MPCs and as a matrix for fibrocartilage tissue engineering applications.

  8. NGF regulates the expression of axonal LINGO-1 to inhibit oligodendrocyte differentiation and myelination.

    Science.gov (United States)

    Lee, Xinhua; Yang, Zhongshu; Shao, Zhaohui; Rosenberg, Sheila S; Levesque, Melissa; Pepinsky, R Blake; Qiu, Mengsheng; Miller, Robert H; Chan, Jonah R; Mi, Sha

    2007-01-03

    Neurons and glia share a mutual dependence in establishing a functional relationship, and none is more evident than the process by which axons control myelination. Here, we identify LRR and Ig domain-containing, Nogo receptor-interacting protein (LINGO-1) as a potent axonal inhibitor of oligodendrocyte differentiation and myelination that is regulated by nerve growth factor and its cognate receptor TrkA in a dose-dependent manner. Whereas LINGO-1 expressed by oligodendrocyte progenitor cells was previously identified as an inhibitor of differentiation, we demonstrate that axonal expression of LINGO-1 inhibits differentiation with equal potency. Disruption of LINGO-1 on either cell type is sufficient to overcome the inhibitory action and promote differentiation and myelination, independent of axon diameter. Furthermore, these results were recapitulated in transgenic mice overexpressing the full length LINGO-1 under the neuronal promoter synapsin. Myelination was greatly inhibited in the presence of enforced axonal LINGO-1. The implications of these results relate specifically to the development of potential therapeutics targeting extrinsic growth factors that may regulate the axonal expression of modulators of oligodendrocyte development.

  9. Neuregulin and BDNF induce a switch to NMDA receptor-dependent myelination by oligodendrocytes.

    Directory of Open Access Journals (Sweden)

    Iben Lundgaard

    2013-12-01

    Full Text Available Myelination is essential for rapid impulse conduction in the CNS, but what determines whether an individual axon becomes myelinated remains unknown. Here we show, using a myelinating coculture system, that there are two distinct modes of myelination, one that is independent of neuronal activity and glutamate release and another that depends on neuronal action potentials releasing glutamate to activate NMDA receptors on oligodendrocyte lineage cells. Neuregulin switches oligodendrocytes from the activity-independent to the activity-dependent mode of myelination by increasing NMDA receptor currents in oligodendrocyte lineage cells 6-fold. With neuregulin present myelination is accelerated and increased, and NMDA receptor block reduces myelination to far below its level without neuregulin. Thus, a neuregulin-controlled switch enhances the myelination of active axons. In vivo, we demonstrate that remyelination after white matter damage is NMDA receptor-dependent. These data resolve controversies over the signalling regulating myelination and suggest novel roles for neuregulin in schizophrenia and in remyelination after white matter damage.

  10. Dimethyl fumarate modulates antioxidant and lipid metabolism in oligodendrocytes

    Directory of Open Access Journals (Sweden)

    He Huang

    2015-08-01

    Full Text Available Oxidative stress contributes to pathology associated with inflammatory brain disorders and therapies that upregulate antioxidant pathways may be neuroprotective in diseases such as multiple sclerosis. Dimethyl fumarate, a small molecule therapeutic for multiple sclerosis, activates cellular antioxidant signaling pathways and may promote myelin preservation. However, it is still unclear what mechanisms may underlie this neuroprotection and whether dimethyl fumarate affects oligodendrocyte responses to oxidative stress. Here, we examine metabolic alterations in oligodendrocytes treated with dimethyl fumarate by using a global metabolomic platform that employs both hydrophilic interaction liquid chromatography–mass spectrometry and shotgun lipidomics. Prolonged treatment of oligodendrocytes with dimethyl fumarate induces changes in citric acid cycle intermediates, glutathione, and lipids, indicating that this compound can directly impact oligodendrocyte metabolism. These metabolic alterations are also associated with protection from oxidant challenge. This study provides insight into the mechanisms by which dimethyl fumarate could preserve myelin integrity in patients with multiple sclerosis.

  11. Epigenetic Mechanisms Facilitating Oligodendrocyte Development, Maturation, and Aging

    NARCIS (Netherlands)

    Copray, Sjef; Huynh, Jimmy Long; Sher, Falak; Casaccia-Bonnefil, Patrizia; Boddeke, Erik

    2009-01-01

    The process of oligodendrocyte differentiation is regulated by a dynamic interaction between a genetic and an epigenetic program. Recent studies, addressing nucleosomal histone modifications have considerably increased our knowledge regarding epigenetic regulation of gene expression during oligodend

  12. Intracellular Ca2+ release through ryanodine receptors contributes to AMPA receptor-mediated mitochondrial dysfunction and ER stress in oligodendrocytes

    Science.gov (United States)

    Ruiz, A; Matute, C; Alberdi, E

    2010-01-01

    Overactivation of ionotropic glutamate receptors in oligodendrocytes induces cytosolic Ca2+ overload and excitotoxic death, a process that contributes to demyelination and multiple sclerosis. Excitotoxic insults cause well-characterized mitochondrial alterations and endoplasmic reticulum (ER) dysfunction, which is not fully understood. In this study, we analyzed the contribution of ER-Ca2+ release through ryanodine receptors (RyRs) and inositol triphosphate receptors (IP3Rs) to excitotoxicity in oligodendrocytes in vitro. First, we observed that oligodendrocytes express all previously characterized RyRs and IP3Rs. Blockade of Ca2+-induced Ca2+ release by TMB-8 following α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) receptor-mediated insults attenuated both oligodendrocyte death and cytosolic Ca2+ overload. In turn, RyR inhibition by ryanodine reduced as well the Ca2+ overload whereas IP3R inhibition was ineffective. Furthermore, AMPA-triggered mitochondrial membrane depolarization, oxidative stress and activation of caspase-3, which in all instances was diminished by RyR inhibition. In addition, we observed that AMPA induced an ER stress response as revealed by α subunit of the eukaryotic initiation factor 2α phosphorylation, overexpression of GRP chaperones and RyR-dependent cleavage of caspase-12. Finally, attenuating ER stress with salubrinal protected oligodendrocytes from AMPA excitotoxicity. Together, these results show that Ca2+ release through RyRs contributes to cytosolic Ca2+ overload, mitochondrial dysfunction, ER stress and cell death following AMPA receptor-mediated excitotoxicity in oligodendrocytes. PMID:21364659

  13. Immune regulatory neural stem/precursor cells protect from central nervous system autoimmunity by restraining dendritic cell function.

    Directory of Open Access Journals (Sweden)

    Stefano Pluchino

    Full Text Available BACKGROUND: The systemic injection of neural stem/precursor cells (NPCs provides remarkable amelioration of the clinico-pathological features of experimental autoimmune encephalomyelitis (EAE. This is dependent on the capacity of transplanted NPCs to engage concurrent mechanisms of action within specific microenvironments in vivo. Among a wide range of therapeutic actions alternative to cell replacement, neuroprotective and immune modulatory capacities of transplanted NPCs have been described. However, lacking is a detailed understanding of the mechanisms by which NPCs exert their therapeutic plasticity. This study was designed to identify the first candidate that exemplifies and sustains the immune modulatory capacity of transplanted NPCs. METHODOLOGY/PRINCIPAL FINDINGS: To achieve the exclusive targeting of the peripheral immune system, SJL mice with PLP-induced EAE were injected subcutaneously with NPCs and the treatment commenced prior to disease onset. NPC-injected EAE mice showed significant clinical improvement, as compared to controls. Exogenous NPCs lacking the expression of major neural antigens were reliably (and for long-term found at the level of draining lymph nodes, while establishing sophisticated anatomical interactions with lymph node cells. Importantly, injected NPCs were never found in organs other than lymph nodes, including the brain and the spinal cord. Draining lymph nodes from transplanted mice showed focal up-regulation of major developmental stem cell regulators, such as BMP-4, Noggin and Sonic hedgehog. In lymph nodes, injected NPCs hampered the activation of myeloid dendritic cells (DCs and steadily restrained the expansion of antigen-specific encephalitogenic T cells. Both ex vivo and in vitro experiments identified a novel highly NPC-specific-BMP-4-dependent-mechanism hindering the DC maturation. CONCLUSION/SIGNIFICANCE: The study described herein, identifies the first member of the TGF beta/BMP family of stem cell

  14. cGMP production of patient-specific iPSCs and photoreceptor precursor cells to treat retinal degenerative blindness.

    Science.gov (United States)

    Wiley, Luke A; Burnight, Erin R; DeLuca, Adam P; Anfinson, Kristin R; Cranston, Cathryn M; Kaalberg, Emily E; Penticoff, Jessica A; Affatigato, Louisa M; Mullins, Robert F; Stone, Edwin M; Tucker, Budd A

    2016-07-29

    Immunologically-matched, induced pluripotent stem cell (iPSC)-derived photoreceptor precursor cells have the potential to restore vision to patients with retinal degenerative diseases like retinitis pigmentosa. The purpose of this study was to develop clinically-compatible methods for manufacturing photoreceptor precursor cells from adult skin in a non-profit cGMP environment. Biopsies were obtained from 35 adult patients with inherited retinal degeneration and fibroblast lines were established under ISO class 5 cGMP conditions. Patient-specific iPSCs were then generated, clonally expanded and validated. Post-mitotic photoreceptor precursor cells were generated using a stepwise cGMP-compliant 3D differentiation protocol. The recapitulation of the enhanced S-cone phenotype in retinal organoids generated from a patient with NR2E3 mutations demonstrated the fidelity of these protocols. Transplantation into immune compromised animals revealed no evidence of abnormal proliferation or tumor formation. These studies will enable clinical trials to test the safety and efficiency of patient-specific photoreceptor cell replacement in humans.

  15. Precursor T-cell acute lymphoblastic leukemia presenting with bone marrow necrosis: a case report

    Directory of Open Access Journals (Sweden)

    Khoshnaw Najmaddin SH

    2012-10-01

    Full Text Available Abstract Introduction Bone marrow necrosis is a clinicopathological condition diagnosed most often at postmortem examination, but it is also seen during the course of malignancy and is not always associated with a poor prognosis. The morphological features of bone marrow necrosis are disruption of the normal marrow architecture and necrosis of myeloid tissue and medullary stroma. Non-malignant conditions associated with bone marrow necrosis are sickle cell anemia, infections, drugs (sulfasalazine, interferon α, all-trans retinoic acid, granulocyte colony-stimulating factor and fludarabine, disseminated intravascular coagulation, antiphospholipid antibody syndrome and acute graft versus host diseases. The malignant causes are leukemia, lymphoma and metastatic carcinomas. Herein we report the case of a patient with precursor T-cell acute lymphoblastic leukemia and bone marrow necrosis at initial presentation. Case presentation A 10-year-old Kurdish boy was presented with generalized bone pain and fever of 1 month’s duration which was associated with sweating, easy fatigability, nose bleeding, breathlessness and severe weight loss. On examination, we observed pallor, tachypnea, tachycardia, low blood pressure, fever, petechial hemorrhage, ecchymoses, tortuous dilated veins over the chest and upper part of abdomen, multiple small cervical lymph node enlargements, mildly enlarged spleen, palpable liver and gross abdominal distention. Blood analysis revealed pancytopenia and elevated lactate dehydrogenase and erythrocyte sedimentation rate. Imaging results showed mediastinal widening on a planar chest X-ray and diffuse focal infiltration of the axial bone marrow on magnetic resonance imaging of the lumbosacral vertebrae. Bone marrow aspiration and biopsy examination showed extensive bone marrow necrosis. Immunophenotyping analysis of the bone marrow biopsy confirmed T-cell acute lymphoblastic leukemia, as CD3 and terminal deoxynucleotidyl

  16. Regulation of biosynthesis of hypusine in Chinese hamster ovary cells. Evidence for eIF-4D precursor polypeptides.

    Science.gov (United States)

    Park, M H

    1987-09-15

    The effects of spermidine depletion and the effects of translation inhibition on hypusine biosynthesis were studied in Chinese hamster ovary cells. Upon depletion of cellular spermidine by treatment with DL-alpha-difluoromethylornithine for 42 h or longer, both the rate of deoxyhypusine + hypusine synthesis and the content of protein-bound hypusine were significantly reduced. Cycloheximide caused complete inhibition of deoxyhypusine + hypusine synthesis in untreated cells and in cells in which the spermidine level was reduced to approximately 10% that of the untreated cells by incubation with DL-alpha-difluoromethylornithine for 24 h. In contrast, the initial synthesis of deoxyhypusine + hypusine was not arrested by cycloheximide in cells depleted of spermidine by treatment with DL-alpha-difluoromethylornithine for 42 h. The initial rate of deoxyhypusine + hypusine production in these spermidine-depleted cells increased 5- to 10-fold when the cellular spermidine level was restored through addition of this polyamine to the culture medium. These findings suggest that in control Chinese hamster ovary cells and in cells containing approximately 10% of the control level of spermidine, deoxyhypusine + hypusine synthesis occurs during or immediately after eukaryotic initiation factor 4D precursor translation. However, in cells during depletion of spermidine, there is an accumulation of an eukaryotic initiation factor 4D precursor that contains no hypusine or deoxyhypusine, and in these cells deoxyhypusine + hypusine synthesis is mainly regulated by the cellular level of spermidine.

  17. Schisandrin B protects PC12 cells by decreasing the expression of amyloid precursor protein and vacuolar protein sorting 35

    Institute of Scientific and Technical Information of China (English)

    Mingmin Yan; Shanping Mao; Huimin Dong; Baohui Liu; Qian Zhang; Gaofeng Pan; Zhiping Fu

    2012-01-01

    PC12 cell injury was induced using 20 μM amyloid β-protein 25-35 to establish a model of Alzheimer's disease.The cells were then treated with 5, 10, and 25 μM Schisandrin B.Methylthiazolyldiphenyl-tetrazolium bromide assays and Hoechst 33342 staining results showed that with increasing Schisandrin B concentration, the survival rate of PC12 cells injured by amyloid β-protein 25-35 gradually increased and the rate of apoptosis gradually decreased.Reverse transcription-PCR, immunocytochemical staining and western blot results showed that with increasing Schisandrin B concentration, the mRNA and protein expression of vacuolar protein sorting 35 and amyloid precursor protein were gradually decreased.Vacuolar protein sorting 35 and amyloid precursor protein showed a consistent trend for change.These findings suggest that 5, 10, and 25 μM Schisandrin B antagonizes the cellular injury induced by amyloid β-protein 25-35 in a dose-dependent manner.This may be caused by decreasing the expression of vacuolar protein sorting 35 and amyloid precursor protein.PC12 cell injury was induced using 20 μM amyloid β-protein 25-35 to establish a model of Alzheimer's disease.The cells were then treated with 5, 10, and 25 μM Schisandrin B.Methylthiazolyldiphenyl-tetrazolium bromide assays and Hoechst 33342 staining results showed that with increasing Schisandrin B concentration, the survival rate of PC12 cells injured by amyloid β-protein 25-35 gradually increased and the rate of apoptosis gradually decreased.Reverse transcription-PCR, immunocytochemical staining and western blot results showed that with increasing Schisandrin B concentration, the mRNA and protein expression of vacuolar protein sorting 35 and amyloid precursor protein were gradually decreased.Vacuolar protein sorting 35 and amyloid precursor protein showed a consistent trend for change.These findings suggest that 5, 10, and 25 μM Schisandrin B antagonizes the cellular injury induced by amyloid β-protein 25

  18. Activation of the aryl hydrocarbon receptor reduces the number of precursor and effector T cells, but preserves thymic CD4(+)CD25(+)Foxp3(+) regulatory T cells

    NARCIS (Netherlands)

    Schulz, V.J.; Smit, J.J.; Bol-Schoenmakers, M.; van Duursen, M.B.M.; van den Berg, M.; Pieters, R.H.H.

    2012-01-01

    Aryl hydrocarbon receptor (AhR) activation suppresses immune responses, including allergic sensitization, by increasing the percentage of regulatory (Treg) cells. Furthermore, AhR activation is known to affect thymic precursor T cells. However, the effect of AhR activation on intrathymic CD4(+)CD25(

  19. Advanced Precursor Reaction Processing for Cu(InGa)(SeS)2 Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Shafarman, William N. [Univ. of Delaware, Newark, DE (United States)

    2015-10-12

    This project “Advanced Precursor Reaction Processing for Cu(InGa)(SeS)2 Solar Cells”, completed by the Institute of Energy Conversion (IEC) at the University of Delaware in collaboration with the Department of Chemical Engineering at the University of Florida, developed the fundamental understanding and technology to increase module efficiency and improve the manufacturability of Cu(InGa)(SeS)2 films using the precursor reaction approach currently being developed by a number of companies. Key results included: (1) development of a three-step H2Se/Ar/H2S reaction process to control Ga distribution through the film and minimizes back contact MoSe2 formation; (2) Ag-alloying to improve precursor homogeneity by avoiding In phase agglomeration, faster reaction and improved adhesion to allow wider reaction process window; (3) addition of Sb, Bi, and Te interlayers at the Mo/precursor junction to produce more uniform precursor morphology and improve adhesion with reduced void formation in reacted films; (4) a precursor structure containing Se and a reaction process to reduce processing time to 5 minutes and eliminate H2Se usage, thereby increasing throughput and reducing costs. All these results were supported by detailed characterization of the film growth, reaction pathways, thermodynamic assessment and device behavior.

  20. Clozapine promotes glycolysis and myelin lipid synthesis in cultured oligodendrocytes

    Directory of Open Access Journals (Sweden)

    Johann eSteiner

    2014-11-01

    Full Text Available Clozapine has stronger systemic metabolic side effects than haloperidol and it was hypothesized that therapeutic antipsychotic and adverse metabolic effects might be related. Considering that cerebral disconnectivity through oligodendrocyte dysfunction has been implicated in schizophrenia, it is important to determine the effect of these drugs on oligodendrocyte energy metabolism and myelin lipid production.Effects of clozapine and haloperidol on glucose and myelin lipid metabolism were evaluated and compared in cultured OLN-93 oligodendrocytes. First, glycolytic activity was assessed by measurement of extra- and intracellular glucose and lactate levels. Next, the expression of glucose (GLUT and monocarboxylate (MCT transporters was determined after 6h and 24h. And finally mitochondrial respiration, acetyl-CoA carboxylase, free fatty acids, and expression of the myelin lipid galactocerebroside were analyzed.Both drugs altered oligodendrocyte glucose metabolism, but in opposite directions. Clozapine improved the glucose uptake, production and release of lactate, without altering GLUT and MCT. In contrast, haloperidol led to higher extracellular levels of glucose and lower levels of lactate, suggesting reduced glycolysis. Antipsychotics did not alter significantly the number of functionally intact mitochondria, but clozapine enhanced the efficacy of oxidative phosphorylation and expression of galactocerebroside.Our findings support the superior impact of clozapine on white matter integrity in schizophrenia as previously observed, suggesting that this drug improves the energy supply and myelin lipid synthesis in oligodendrocytes. Characterizing the underlying signal transduction pathways may pave the way for novel oligodendrocyte-directed schizophrenia therapies.

  1. A co-culture model of the hippocampal neurogenic niche reveals differential effects of astrocytes, endothelial cells and pericytes on proliferation and differentiation of adult murine precursor cells

    Directory of Open Access Journals (Sweden)

    Fanny Ehret

    2015-11-01

    Full Text Available The niche concept of stem cell biology proposes a functional unit between the precursor cells and their local microenvironment, to which several cell types might contribute by cell–cell contacts, extracellular matrix, and humoral factors. We here established three co-culture models (with cell types separated by membrane for both adherent monolayers and neurospheres to address the potential influence of different niche cell types in the neurogenic zone of the adult hippocampus of mice. Astrocytes and endothelial cells enhanced precursor cell proliferation and neurosphere formation. Endothelial factors also led to a prolonged increase in proliferation after growth factor withdrawal, which otherwise induces differentiation. All niche cell types enhanced cell survival in monolayer cultures, endothelial cells also stimulated neuronal differentiation. A parallel trend elicited by astrocytes did not reach conventional statistical significance. Pericytes had variable effects here. We did not observe changes in differentiation in neurosphere co-cultures. In summary, our data indicate that in precursor cell culture protocols survival could be improved by adding as yet unknown factors physiologically contributed by astrocytes and endothelial cells. Our findings also underscore the complexity of the niche and the differential impact of factors from the different sources on distinct aspects of neuronal development. With the help of the models presented here, identification of these factors and their specific biological activity can now be initiated.

  2. Planar Cell Polarity Breaks the Symmetry of PAR Protein Distribution prior to Mitosis in Drosophila Sensory Organ Precursor Cells.

    Science.gov (United States)

    Besson, Charlotte; Bernard, Fred; Corson, Francis; Rouault, Hervé; Reynaud, Elodie; Keder, Alyona; Mazouni, Khalil; Schweisguth, François

    2015-04-20

    During development, cell-fate diversity can result from the unequal segregation of fate determinants at mitosis. Polarization of the mother cell is essential for asymmetric cell division (ACD). It often involves the formation of a cortical domain containing the PAR complex proteins Par3, Par6, and atypical protein kinase C (aPKC). In the fly notum, sensory organ precursor cells (SOPs) divide asymmetrically within the plane of the epithelium and along the body axis to generate two distinct cells. Fate asymmetry depends on the asymmetric localization of the PAR complex. In the absence of planar cell polarity (PCP), SOPs divide with a random planar orientation but still asymmetrically, showing that PCP is dispensable for PAR asymmetry at mitosis. To study when and how the PAR complex localizes asymmetrically, we have used a quantitative imaging approach to measure the planar polarization of the proteins Bazooka (Baz, fly Par3), Par6, and aPKC in living pupae. By using imaging of functional GFP-tagged proteins with image processing and computational modeling, we find that Baz, Par6, and aPKC become planar polarized prior to mitosis in a manner independent of the AuroraA kinase and that PCP is required for the planar polarization of Baz, Par6, and aPKC during interphase. This indicates that a "mitosis rescue" mechanism establishes asymmetry at mitosis in PCP mutants. This study therefore identifies PCP as the initial symmetry-breaking signal for the planar polarization of PAR proteins in asymmetrically dividing SOPs.

  3. Chemokines influence the migration and fate of neural precursor cells from the young adult and middle-aged rat subventricular zone.

    Science.gov (United States)

    Gordon, R J; Mehrabi, N F; Maucksch, C; Connor, B

    2012-01-01

    We have previously demonstrated a role for the chemokines MCP-1, MIP-1α and GRO-α in directing subventricular zone (SVZ)-derived neural precursor cell migration towards the site of cell death in the adult rodent brain. However the influence of chemokines such as MCP-1, MIP-1α and GRO-α on the differentiation of adult neural precursor cells has not previously been investigated. Further, as the majority of neurological disorders and injuries occur during ageing, it is important to investigate the effect of chemokines on adult neural precursor cell cultures obtained from the ageing brain. This study therefore examined the effect of MCP-1, MIP-1α and GRO-α on SVZ-derived neural precursor cell differentiation in vitro, and assessed whether precursor cells from the middle-aged rat brain (13 months old) follow the same migratory and differential profile as neural precursor cells obtained from the young adult rat brain (2 months old). We observed that each of the chemokines examined generated differing effects in regards to neuronal or glial differentiation. Further, both MIP-1α and GRO-α increased total cell number, suggesting an effect on precursor cell proliferation and/or survival. In agreement with cultures obtained from young adult brains, SVZ-derived neural precursor cells cultured from the middle-aged brain exhibited chemotactic migration in response to a concentration gradient. These results indicate that the chemokines MCP-1, MIP-1α and GRO-α can influence both the migration and fate choice of SVZ-derived neural precursor cells, as well as promoting cell viability. While a response to each of these chemokines is maintained in the middle-aged brain, a distinct age-related alteration in differential fate can be identified.

  4. B7 / CD28 in central tolerance: costimulation promotes maturation of regulatory T cell precursors and prevents their clonal deletion

    Directory of Open Access Journals (Sweden)

    Maria eHinterberger

    2011-07-01

    Full Text Available According to the two-step model, the intrathymic generation of CD4+ regulatory T (Treg cells segregates into a first, T cell receptor (TCR-driven phase and a second, cytokine dependent phase. The initial TCR stimulus gives rise to a CD25+Foxp3– developmental intermediate. These precursors subsequently require cytokine signaling to establish the mature CD25+Foxp3+ Treg cell phenotype. In addition, costimulation via CD28 / B7 (CD80/86 axis is important for the generation of a Treg cell repertoire of normal size. Recent data suggest that CD28 or B7 deficient mice lack CD25+Foxp3– Treg cell progenitors. However, these data leave open whether costimulation is also required at subsequent stages of Treg differentiation. Also, the fate of presumptive Treg cells carrying a permissive TCR specificity in the absence of costimulation remains to be established. Here, we have used a previously described TCR transgenic model