1
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Brown RI, Barber HM, Kucenas S. Satellite glial cell manipulation prior to axotomy enhances developing dorsal root ganglion central branch regrowth into the spinal cord. Glia 2024; 72:1766-1784. [PMID: 39141572 PMCID: PMC11325082 DOI: 10.1002/glia.24581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 05/30/2024] [Accepted: 06/02/2024] [Indexed: 08/16/2024]
Abstract
The central and peripheral nervous systems (CNS and PNS, respectively) exhibit remarkable diversity in the capacity to regenerate following neuronal injury with PNS injuries being much more likely to regenerate than those that occur in the CNS. Glial responses to damage greatly influence the likelihood of regeneration by either promoting or inhibiting axonal regrowth over time. However, despite our understanding of how some glial lineages participate in nerve degeneration and regeneration, less is known about the contributions of peripheral satellite glial cells (SGC) to regeneration failure following central axon branch injury of dorsal root ganglia (DRG) sensory neurons. Here, using in vivo, time-lapse imaging in larval zebrafish coupled with laser axotomy, we investigate the role of SGCs in axonal regeneration. In our studies we show that SGCs respond to injury by relocating their nuclei to the injury site during the same period that DRG neurons produce new central branch neurites. Laser ablation of SGCs prior to axon injury results in more neurite growth attempts and ultimately a higher rate of successful central axon regrowth, implicating SGCs as inhibitors of regeneration. We also demonstrate that this SGC response is mediated in part by ErbB signaling, as chemical inhibition of this receptor results in reduced SGC motility and enhanced central axon regrowth. These findings provide new insights into SGC-neuron interactions under injury conditions and how these interactions influence nervous system repair.
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Affiliation(s)
- Robin I Brown
- Department of Biology, University of Virginia, Charlottesville, Virginia, USA
- Program in Fundamental Neuroscience, University of Virginia, Charlottesville, Virginia, USA
| | - Heather M Barber
- Program in Fundamental Neuroscience, University of Virginia, Charlottesville, Virginia, USA
- Cell & Developmental Biology Graduate Program, University of Virginia, Charlottesville, Virginia, USA
| | - Sarah Kucenas
- Department of Biology, University of Virginia, Charlottesville, Virginia, USA
- Program in Fundamental Neuroscience, University of Virginia, Charlottesville, Virginia, USA
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2
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Curran BM, Nickerson KR, Yung AR, Goodrich LV, Jaworski A, Tessier-Lavigne M, Ma L. Multiple guidance mechanisms control axon growth to generate precise T-shaped bifurcation during dorsal funiculus development in the spinal cord. eLife 2024; 13:RP94109. [PMID: 39159057 PMCID: PMC11333043 DOI: 10.7554/elife.94109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/21/2024] Open
Abstract
The dorsal funiculus in the spinal cord relays somatosensory information to the brain. It is made of T-shaped bifurcation of dorsal root ganglion (DRG) sensory axons. Our previous study has shown that Slit signaling is required for proper guidance during bifurcation, but loss of Slit does not affect all DRG axons. Here, we examined the role of the extracellular molecule Netrin-1 (Ntn1). Using wholemount staining with tissue clearing, we showed that mice lacking Ntn1 had axons escaping from the dorsal funiculus at the time of bifurcation. Genetic labeling confirmed that these misprojecting axons come from DRG neurons. Single axon analysis showed that loss of Ntn1 did not affect bifurcation but rather altered turning angles. To distinguish their guidance functions, we examined mice with triple deletion of Ntn1, Slit1, and Slit2 and found a completely disorganized dorsal funiculus. Comparing mice with different genotypes using immunolabeling and single axon tracing revealed additive guidance errors, demonstrating the independent roles of Ntn1 and Slit. Moreover, the same defects were observed in embryos lacking their cognate receptors. These in vivo studies thus demonstrate the presence of multi-factorial guidance mechanisms that ensure proper formation of a common branched axonal structure during spinal cord development.
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Affiliation(s)
- Bridget M Curran
- Department of Neuroscience, Jefferson Synaptic Biology Center, Vickie and Jack Farber, Institute for Neuroscience, Sydney Kimmel Medical College, Thomas Jefferson UniversityPhiladelphiaUnited States
| | - Kelsey R Nickerson
- Department of Neuroscience, Brown UniversityProvidenceUnited States
- Robert J. and Nancy D. Carney Institute for Brain ScienceProvidenceUnited States
| | - Andrea R Yung
- Department of Neurobiology, Harvard Medical SchoolBostonUnited States
| | - Lisa V Goodrich
- Department of Neurobiology, Harvard Medical SchoolBostonUnited States
| | - Alexander Jaworski
- Department of Neuroscience, Brown UniversityProvidenceUnited States
- Robert J. and Nancy D. Carney Institute for Brain ScienceProvidenceUnited States
| | | | - Le Ma
- Department of Neuroscience, Jefferson Synaptic Biology Center, Vickie and Jack Farber, Institute for Neuroscience, Sydney Kimmel Medical College, Thomas Jefferson UniversityPhiladelphiaUnited States
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3
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Curran BM, Nickerson KR, Yung AR, Goodrich LV, Jaworski A, Tessier-Lavigne M, Ma L. Multiple Guidance Mechanisms Control Axon Growth to Generate Precise T-shaped Bifurcation during Dorsal Funiculus Development in the Spinal Cord. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.11.17.567638. [PMID: 38014092 PMCID: PMC10680847 DOI: 10.1101/2023.11.17.567638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
The dorsal funiculus in the spinal cord relays somatosensory information to the brain. It is made of T-shaped bifurcation of dorsal root ganglion (DRG) sensory axons. Our previous study has shown that Slit signaling is required for proper guidance during bifurcation, but loss of Slit does not affect all DRG axons. Here, we examined the role of the extracellular molecule Netrin-1 (Ntn1). Using wholemount staining with tissue clearing, we showed that mice lacking Ntn1 have axons escaping from the dorsal funiculus at the time of bifurcation. Genetic labeling confirmed that these misprojecting axons come from DRG neurons. Single axon analysis showed that loss of Ntn1 does not affect bifurcation but rather alters turning angles. To distinguish their guidance functions, we examined mice with triple deletion of Ntn1, Slit1, and Slit2 and found a completely disorganized dorsal funiculus. Comparing mice with different genotypes using immunolabeling and single axon tracing revealed additive guidance errors, demonstrating the independent roles of Ntn1 and Slit. Moreover, the same defects were observed in embryos lacking their cognate receptors. These in vivo studies thus demonstrate the presence of multi-factorial guidance mechanisms that ensure proper formation of a common branched axonal structure during spinal cord development.
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Affiliation(s)
- Bridget M Curran
- Department of Neuroscience, Jefferson Synaptic Biology Center, Vickie and Jack Farber Institute for Neuroscience, Sydney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107
| | - Kelsey R Nickerson
- Department of Neuroscience, Brown University, Providence, RI 02912
- Robert J. and Nancy D. Carney Institute for Brain Science, Providence, RI 02912
| | - Andrea R Yung
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115
| | - Lisa V Goodrich
- Department of Neurobiology, Harvard Medical School, Boston, MA 02115
| | - Alexander Jaworski
- Department of Neuroscience, Brown University, Providence, RI 02912
- Robert J. and Nancy D. Carney Institute for Brain Science, Providence, RI 02912
| | | | - Le Ma
- Department of Neuroscience, Jefferson Synaptic Biology Center, Vickie and Jack Farber Institute for Neuroscience, Sydney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107
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4
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Trolle C, Han Y, Mutt SJ, Christoffersson G, Kozlova EN. Boundary cap neural crest stem cells promote angiogenesis after transplantation to avulsed dorsal roots in mice and induce migration of endothelial cells in 3D printed scaffolds. Neurosci Lett 2024; 826:137724. [PMID: 38467271 DOI: 10.1016/j.neulet.2024.137724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Revised: 02/26/2024] [Accepted: 03/08/2024] [Indexed: 03/13/2024]
Abstract
Dorsal root avulsion injuries lead to loss of sensation and to reorganization of blood vessels (BVs) in the injured area. The inability of injured sensory axons to re-enter the spinal cord results in permanent loss of sensation, and often also leads to the development of neuropathic pain. Approaches that restore connection between peripheral sensory axons and their CNS targets are thus urgently need. Previous research has shown that sensory axons from peripherally grafted human sensory neurons are able to enter the spinal cord by growing along BVs which penetrate the CNS from the spinal cord surface. In this study we analysed the distribution of BVs after avulsion injury and how their pattern is affected by implantation at the injury site of boundary cap neural crest stem cells (bNCSCs), a transient cluster of cells, which are located at the boundary between the spinal cord and peripheral nervous system and assist the growth of sensory axons from periphery into the spinal cord during development. The superficial dorsal spinal cord vasculature was examined using intravital microscopy and intravascular BV labelling. bNCSC transplantation increased vascular volume in a non-dose responsive manner, whereas dorsal root avulsion alone did not decrease the vascular volume. To determine whether bNCSC are endowed with angiogenic properties we prepared 3D printed scaffolds, containing bNCSCs together with rings prepared from mouse aorta. We show that bNCSC do induce migration and assembly of endothelial cells in this system. These findings suggest that bNCSC transplant can promote vascularization in vivo and contribute to BV formation in 3D printed scaffolds.
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Affiliation(s)
- Carl Trolle
- Department of Medical Sciences, Uppsala University Hospital, Rehabilitation Medicine, 751 85 Uppsala, Sweden
| | - Yilin Han
- Department of Immunology, Genetics and Pathology, Uppsala University Biomedical Center, PO Box 815, 751 08 Uppsala, Sweden
| | - Shivaprakash Jagalur Mutt
- Department of Medical Cell Biology, Science for Life Laboratory, Uppsala University, PO Box 571, 751 23 Uppsala, Sweden
| | - Gustaf Christoffersson
- Department of Medical Cell Biology, Science for Life Laboratory, Uppsala University, PO Box 571, 751 23 Uppsala, Sweden
| | - Elena N Kozlova
- Department of Immunology, Genetics and Pathology, Uppsala University Biomedical Center, PO Box 815, 751 08 Uppsala, Sweden.
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5
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Chu Y, Jia S, Xu K, Liu Q, Mai L, Liu J, Fan W, Huang F. Single-cell transcriptomic profile of satellite glial cells in trigeminal ganglion. Front Mol Neurosci 2023; 16:1117065. [PMID: 36818656 PMCID: PMC9932514 DOI: 10.3389/fnmol.2023.1117065] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 01/16/2023] [Indexed: 02/05/2023] Open
Abstract
Satellite glial cells (SGCs) play an important role in regulating the function of trigeminal ganglion (TG) neurons. Multiple mediators are involved in the bidirectional communication between SGCs and neurons in different physiological and pathological states. However, molecular insights into the transcript characteristics of SGCs are limited. Moreover, little is known about the heterogeneity of SGCs in TG, and a more in-depth understanding of the interactions between SGCs and neuron subtypes is needed. Here we show the single-cell RNA sequencing (scRNA-seq) profile of SGCs in TG under physiological conditions. Our results demonstrate TG includes nine types of cell clusters, such as neurons, SGCs, myeloid Schwann cells (mSCs), non-myeloid Schwann cells (nmSCs), immune cells, etc., and the corresponding markers are also presented. We reveal the signature gene expression of SGCs, mSCs and nmSCs in the TG, and analyze the ligand-receptor pairs between neuron subtypes and SGCs in the TG. In the heterogeneity analysis of SGCs, four SGCs subtypes are identified, including subtypes enriched for genes associated with extracellular matrix organization, immediate early genes, interferon beta, and cell adhesion molecules, respectively. Our data suggest the molecular characteristics, heterogeneity of SGCs, and bidirectional interactions between SGCs and neurons, providing a valuable resource for studying SGCs in the TG.
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Affiliation(s)
- Yanhao Chu
- Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China,Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Shilin Jia
- Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China,Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Ke Xu
- Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China,Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Qing Liu
- Paediatric Dentistry and Orthodontics, Faculty of Dentistry, The University of Hong Kong, Pokfulam, Hong Kong SAR, China
| | - Lijia Mai
- Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China,Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Jiawei Liu
- Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China,Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Wenguo Fan
- Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China,Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China,*Correspondence: Wenguo Fan, ; Fang Huang,
| | - Fang Huang
- Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China,Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China,*Correspondence: Wenguo Fan, ; Fang Huang,
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6
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Borda M, Aquino JB, Mazzone GL. Cell-based experimental strategies for myelin repair in multiple sclerosis. J Neurosci Res 2023; 101:86-111. [PMID: 36164729 DOI: 10.1002/jnr.25129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 08/21/2022] [Accepted: 09/09/2022] [Indexed: 11/10/2022]
Abstract
Multiple sclerosis (MS) is an autoimmune demyelinating disorder of the central nervous system (CNS), diagnosed at a mean age of 32 years. CNS glia are crucial players in the onset of MS, primarily involving astrocytes and microglia that can cause/allow massive oligodendroglial cells death, without immune cell infiltration. Current therapeutic approaches are aimed at modulating inflammatory reactions during relapsing episodes, but lack the ability to induce very significant repair mechanisms. In this review article, different experimental approaches based mainly on the application of different cell types as therapeutic strategies applied for the induction of myelin repair and/or the amelioration of the disease are discussed. Regarding this issue, different cell sources were applied in various experimental models of MS, with different results, both in significant improvements in remyelination and the reduction of neuroinflammation and glial activation, or in neuroprotection. All cell types tested have advantages and disadvantages, which makes it difficult to choose a better option for therapeutic application in MS. New strategies combining cell-based treatment with other applications would result in further improvements and would be good candidates for MS cell therapy and myelin repair.
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Affiliation(s)
- Maximiliano Borda
- Instituto de Investigaciones en Medicina Traslacional (IIMT), CONICET-Universidad Austral, Derqui, Pilar, Buenos Aires, Argentina
| | - Jorge B Aquino
- Instituto de Investigaciones en Medicina Traslacional (IIMT), CONICET-Universidad Austral, Derqui, Pilar, Buenos Aires, Argentina.,CONICET, Comisión Nacional de Investigaciones Científicas y Técnicas
| | - Graciela L Mazzone
- Instituto de Investigaciones en Medicina Traslacional (IIMT), CONICET-Universidad Austral, Derqui, Pilar, Buenos Aires, Argentina.,CONICET, Comisión Nacional de Investigaciones Científicas y Técnicas
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7
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Reed CB, Feltri ML, Wilson ER. Peripheral glia diversity. J Anat 2022; 241:1219-1234. [PMID: 34131911 PMCID: PMC8671569 DOI: 10.1111/joa.13484] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 05/20/2021] [Accepted: 05/26/2021] [Indexed: 12/13/2022] Open
Abstract
Recent years have seen an evolving appreciation for the role of glial cells in the nervous system. As we move away from the typical neurocentric view of neuroscience, the complexity and variability of central nervous system glia is emerging, far beyond the three main subtypes: astrocytes, oligodendrocytes, and microglia. Yet the diversity of the glia found in the peripheral nervous system remains rarely discussed. In this review, we discuss the developmental origin, morphology, and function of the different populations of glia found in the peripheral nervous system, including: myelinating Schwann cells, Remak Schwann cells, repair Schwann cells, satellite glia, boundary cap-derived glia, perineurial glia, terminal Schwann cells, glia found in the skin, olfactory ensheathing cells, and enteric glia. The morphological and functional heterogeneity of glia found in the periphery reflects the diverse roles the nervous system performs throughout the body. Further, it highlights a complexity that should be appreciated and considered when it comes to a complete understanding of the peripheral nervous system in health and disease.
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Affiliation(s)
- Chelsey B Reed
- Hunter James Kelly Research Institute, Jacobs School of Medicine and Biomedical Sciences State, University of New York at Buffalo, Buffalo, New York, USA
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York, USA
| | - M Laura Feltri
- Hunter James Kelly Research Institute, Jacobs School of Medicine and Biomedical Sciences State, University of New York at Buffalo, Buffalo, New York, USA
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York, USA
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York, USA
| | - Emma R Wilson
- Hunter James Kelly Research Institute, Jacobs School of Medicine and Biomedical Sciences State, University of New York at Buffalo, Buffalo, New York, USA
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York, USA
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8
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Ge LL, Xing MY, Zhang HB, Wang ZC. Neurofibroma Development in Neurofibromatosis Type 1: Insights from Cellular Origin and Schwann Cell Lineage Development. Cancers (Basel) 2022; 14:cancers14184513. [PMID: 36139671 PMCID: PMC9497298 DOI: 10.3390/cancers14184513] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 09/11/2022] [Accepted: 09/14/2022] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Neurofibromatosis type 1 (NF1), a genetic tumor predisposition syndrome that affects about 1 in 3000 newborns, is caused by mutations in the NF1 gene and subsequent inactivation of its encoded neurofibromin. Neurofibromin is a tumor suppressor protein involved in the downregulation of Ras signaling. Despite a diverse clinical spectrum, one of several hallmarks of NF1 is a peripheral nerve sheath tumor (PNST), which comprises mixed nervous and fibrous components. The distinct spatiotemporal characteristics of plexiform and cutaneous neurofibromas have prompted hypotheses about the origin and developmental features of these tumors, involving various cellular transition processes. METHODS We retrieved published literature from PubMed, EMBASE, and Web of Science up to 21 June 2022 and searched references cited in the selected studies to identify other relevant papers. Original articles reporting the pathogenesis of PNSTs during development were included in this review. We highlighted the Schwann cell (SC) lineage shift to better present the evolution of its corresponding cellular origin hypothesis and its important effects on the progression and malignant transformation of neurofibromas. CONCLUSIONS In this review, we summarized the vast array of evidence obtained on the full range of neurofibroma development based on cellular and molecular pathogenesis. By integrating findings relating to tumor formation, growth, and malignancy, we hope to reveal the role of SC lineage shift as well as the combined impact of additional determinants in the natural history of PNSTs.
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Affiliation(s)
- Ling-Ling Ge
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People′s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China
| | - Ming-Yan Xing
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200011, China
| | - Hai-Bing Zhang
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200011, China
- Correspondence: (H.-B.Z.); or (Z.-C.W.); Tel.: +86-021-54920988 (H.-B.Z.); +86-021-53315120 (Z.-C.W.)
| | - Zhi-Chao Wang
- Department of Plastic and Reconstructive Surgery, Shanghai Ninth People′s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China
- Correspondence: (H.-B.Z.); or (Z.-C.W.); Tel.: +86-021-54920988 (H.-B.Z.); +86-021-53315120 (Z.-C.W.)
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9
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Sinegubov A, Andreeva D, Burzak N, Vasyutina M, Murashova L, Dyachuk V. Heterogeneity and Potency of Peripheral Glial Cells in Embryonic Development and Adults. Front Mol Neurosci 2022; 15:737949. [PMID: 35401107 PMCID: PMC8990813 DOI: 10.3389/fnmol.2022.737949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 02/08/2022] [Indexed: 11/13/2022] Open
Abstract
This review describes the heterogeneity of peripheral glial cell populations, from the emergence of Schwann cells (SCs) in early development, to their involvement, and that of their derivatives in adult glial populations. We focus on the origin of the first glial precursors from neural crest cells (NCCs), and their ability to differentiate into several cell types during development. We also discuss the heterogeneity of embryonic glia in light of the latest data from genetic tracing and transcriptome analysis. Special attention has been paid to the biology of glial populations in adult animals, by highlighting common features of different glial cell types and molecular differences that modulate their functions. Finally, we consider the communication of glial cells with axons of neurons in normal and pathological conditions. In conclusion, the present review details how information available on glial cell types and their functions in normal and pathological conditions may be utilized in the development of novel therapeutic strategies for the treatment of patients with neurodiseases.
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10
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Kolos EA, Korzhevskii DE. Glutamine Synthetase in the Cells of the Developing Rat Spinal Cord. Russ J Dev Biol 2021. [DOI: 10.1134/s1062360421050040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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11
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Solovieva T, Bronner M. Reprint of: Schwann cell precursors: Where they come from and where they go. Cells Dev 2021; 168:203729. [PMID: 34456178 DOI: 10.1016/j.cdev.2021.203729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 04/29/2021] [Accepted: 04/30/2021] [Indexed: 10/20/2022]
Abstract
Schwann cell precursors (SCPs) are a transient population in the embryo, closely associated with nerves along which they migrate into the periphery of the body. Long considered to be progenitors that only form Schwann cells-the myelinating cells of nerves, current evidence suggests that SCPs have much broader developmental potential. Indeed, different cell marking techniques employed over the past 20 years have identified multiple novel SCP derivatives throughout the body. It is now clear that SCPs represent a multipotent progenitor population, which also display a level of plasticity in response to injury. Moreover, they originate from multiple origins in the embryo and may reflect several distinct subpopulations in terms of molecular identity and fate. Here we review SCP origins, derivatives and plasticity in development, growth and repair.
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Affiliation(s)
- Tatiana Solovieva
- Division of Biology and Biological Engineering, California Institute of Technology, United States of America.
| | - Marianne Bronner
- Division of Biology and Biological Engineering, California Institute of Technology, United States of America
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12
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Aldskogius H, Kozlova EN. Dorsal Root Injury-A Model for Exploring Pathophysiology and Therapeutic Strategies in Spinal Cord Injury. Cells 2021; 10:2185. [PMID: 34571835 PMCID: PMC8470715 DOI: 10.3390/cells10092185] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 08/19/2021] [Accepted: 08/20/2021] [Indexed: 12/12/2022] Open
Abstract
Unraveling the cellular and molecular mechanisms of spinal cord injury is fundamental for our possibility to develop successful therapeutic approaches. These approaches need to address the issues of the emergence of a non-permissive environment for axonal growth in the spinal cord, in combination with a failure of injured neurons to mount an effective regeneration program. Experimental in vivo models are of critical importance for exploring the potential clinical relevance of mechanistic findings and therapeutic innovations. However, the highly complex organization of the spinal cord, comprising multiple types of neurons, which form local neural networks, as well as short and long-ranging ascending or descending pathways, complicates detailed dissection of mechanistic processes, as well as identification/verification of therapeutic targets. Inducing different types of dorsal root injury at specific proximo-distal locations provide opportunities to distinguish key components underlying spinal cord regeneration failure. Crushing or cutting the dorsal root allows detailed analysis of the regeneration program of the sensory neurons, as well as of the glial response at the dorsal root-spinal cord interface without direct trauma to the spinal cord. At the same time, a lesion at this interface creates a localized injury of the spinal cord itself, but with an initial neuronal injury affecting only the axons of dorsal root ganglion neurons, and still a glial cell response closely resembling the one seen after direct spinal cord injury. In this review, we provide examples of previous research on dorsal root injury models and how these models can help future exploration of mechanisms and potential therapies for spinal cord injury repair.
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Affiliation(s)
- Håkan Aldskogius
- Laboratory of Regenertive Neurobiology, Biomedical Center, Department of Neuroscience, Uppsala University, 75124 Uppsala, Sweden;
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13
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Solovieva T, Bronner M. Schwann cell precursors: Where they come from and where they go. Cells Dev 2021; 166:203686. [PMID: 33994354 DOI: 10.1016/j.cdev.2021.203686] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 04/29/2021] [Accepted: 04/30/2021] [Indexed: 11/30/2022]
Abstract
Schwann cell precursors (SCPs) are a transient population in the embryo, closely associated with nerves along which they migrate into the periphery of the body. Long considered to be progenitors that only form Schwann cells-the myelinating cells of nerves, current evidence suggests that SCPs have much broader developmental potential. Indeed, different cell marking techniques employed over the past 20 years have identified multiple novel SCP derivatives throughout the body. It is now clear that SCPs represent a multipotent progenitor population, which also display a level of plasticity in response to injury. Moreover, they originate from multiple origins in the embryo and may reflect several distinct subpopulations in terms of molecular identity and fate. Here we review SCP origins, derivatives and plasticity in development, growth and repair.
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Affiliation(s)
- Tatiana Solovieva
- Division of Biology and Biological Engineering, California Institute of Technology, United States of America.
| | - Marianne Bronner
- Division of Biology and Biological Engineering, California Institute of Technology, United States of America
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14
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Yusifov E, Dumoulin A, Stoeckli ET. Investigating Primary Cilia during Peripheral Nervous System Formation. Int J Mol Sci 2021; 22:3176. [PMID: 33804711 PMCID: PMC8003989 DOI: 10.3390/ijms22063176] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/16/2021] [Accepted: 03/16/2021] [Indexed: 12/22/2022] Open
Abstract
The primary cilium plays a pivotal role during the embryonic development of vertebrates. It acts as a somatic signaling hub for specific pathways, such as Sonic Hedgehog signaling. In humans, mutations in genes that cause dysregulation of ciliogenesis or ciliary function lead to severe developmental disorders called ciliopathies. Beyond its role in early morphogenesis, growing evidence points towards an essential function of the primary cilium in neural circuit formation in the central nervous system. However, very little is known about a potential role in the formation of the peripheral nervous system. Here, we investigate the presence of the primary cilium in neural crest cells and their derivatives in the trunk of developing chicken embryos in vivo. We found that neural crest cells, sensory neurons, and boundary cap cells all bear a primary cilium during key stages of early peripheral nervous system formation. Moreover, we describe differences in the ciliation of neuronal cultures of different populations from the peripheral and central nervous systems. Our results offer a framework for further in vivo and in vitro investigations on specific roles that the primary cilium might play during peripheral nervous system formation.
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Affiliation(s)
| | | | - Esther T. Stoeckli
- Department of Molecular Life Sciences and Neuroscience Center Zurich, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland; (E.Y.); (A.D.)
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15
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Lago-Baldaia I, Fernandes VM, Ackerman SD. More Than Mortar: Glia as Architects of Nervous System Development and Disease. Front Cell Dev Biol 2020; 8:611269. [PMID: 33381506 PMCID: PMC7767919 DOI: 10.3389/fcell.2020.611269] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 11/17/2020] [Indexed: 12/12/2022] Open
Abstract
Glial cells are an essential component of the nervous system of vertebrates and invertebrates. In the human brain, glia are as numerous as neurons, yet the importance of glia to nearly every aspect of nervous system development has only been expounded over the last several decades. Glia are now known to regulate neural specification, synaptogenesis, synapse function, and even broad circuit function. Given their ubiquity, it is not surprising that the contribution of glia to neuronal disease pathogenesis is a growing area of research. In this review, we will summarize the accumulated evidence of glial participation in several distinct phases of nervous system development and organization-neural specification, circuit wiring, and circuit function. Finally, we will highlight how these early developmental roles of glia contribute to nervous system dysfunction in neurodevelopmental and neurodegenerative disorders.
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Affiliation(s)
- Inês Lago-Baldaia
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Vilaiwan M. Fernandes
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Sarah D. Ackerman
- Institute of Neuroscience, Howard Hughes Medical Institute, University of Oregon, Eugene, OR, United States
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16
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Distal spinal nerve development and divergence of avian groups. Sci Rep 2020; 10:6303. [PMID: 32286419 PMCID: PMC7156524 DOI: 10.1038/s41598-020-63264-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 03/26/2020] [Indexed: 11/16/2022] Open
Abstract
The avian transition from long to short, distally fused tails during the Mesozoic ushered in the Pygostylian group, which includes modern birds. The avian tail embodies a bipartite anatomy, with the proximal separate caudal vertebrae region, and the distal pygostyle, formed by vertebral fusion. This study investigates developmental features of the two tail domains in different bird groups, and analyzes them in reference to evolutionary origins. We first defined the early developmental boundary between the two tail halves in the chicken, then followed major developmental structures from early embryo to post-hatching stages. Differences between regions were observed in sclerotome anterior/posterior polarity and peripheral nervous system development, and these were consistent in other neognathous birds. However, in the paleognathous emu, the neognathous pattern was not observed, such that spinal nerve development extends through the pygostyle region. Disparities between the neognaths and paleognaths studied were also reflected in the morphology of their pygostyles. The ancestral long-tailed spinal nerve configuration was hypothesized from brown anole and alligator, which unexpectedly more resembles the neognathous birds. This study shows that tail anatomy is not universal in avians, and suggests several possible scenarios regarding bird evolution, including an independent paleognathous long-tailed ancestor.
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17
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Suter TACS, Jaworski A. Cell migration and axon guidance at the border between central and peripheral nervous system. Science 2020; 365:365/6456/eaaw8231. [PMID: 31467195 DOI: 10.1126/science.aaw8231] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 07/22/2019] [Indexed: 12/13/2022]
Abstract
The central and peripheral nervous system (CNS and PNS, respectively) are composed of distinct neuronal and glial cell types with specialized functional properties. However, a small number of select cells traverse the CNS-PNS boundary and connect these two major subdivisions of the nervous system. This pattern of segregation and selective connectivity is established during embryonic development, when neurons and glia migrate to their destinations and axons project to their targets. Here, we provide an overview of the cellular and molecular mechanisms that control cell migration and axon guidance at the vertebrate CNS-PNS border. We highlight recent advances on how cell bodies and axons are instructed to either cross or respect this boundary, and present open questions concerning the development and plasticity of the CNS-PNS interface.
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Affiliation(s)
- Tracey A C S Suter
- Department of Neuroscience, Division of Biology and Medicine, Brown University, Providence, RI 02912, USA.,Robert J. and Nancy D. Carney Institute for Brain Science, Providence, RI 02912, USA
| | - Alexander Jaworski
- Department of Neuroscience, Division of Biology and Medicine, Brown University, Providence, RI 02912, USA. .,Robert J. and Nancy D. Carney Institute for Brain Science, Providence, RI 02912, USA
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18
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Collins A, Ibrahim A, Li D, Liadi M, Li Y. Reconstruction of the Damaged Dorsal Root Entry Zone by Transplantation of Olfactory Ensheathing Cells. Cell Transplant 2019; 28:1212-1219. [PMID: 31271055 PMCID: PMC6767882 DOI: 10.1177/0963689719855938] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The dorsal root entry zone is often used in research to examine the disconnection between
the central and peripheral parts of the nervous system which occurs following injury. Our
laboratory and others have used transplantation of olfactory ensheathing cells (OECs) to
repair experimental spinal cord injuries. We have previously used a four dorsal root
(C6–T1) transection model to show that transplantation of OECs can reinstate rat forelimb
proprioception in a climbing task. Until now, however, we have not looked in detail at the
anatomical interaction between OECs and the peripheral/central nervous system regions
which form the transitional zone. In this study, we compared short- and long-term OEC
survival and their interaction with the surrounding dorsal root tissue. We reveal how
transplanted OECs orient toward the spinal cord and allow newly formed axons to travel
across into the dorsal horn of the spinal cord. Reconstruction of the dorsal root entry
zone was supported by OEC ensheathment of axons at the injured site and also at around 3
mm further away at the dorsal root ganglion. Quantitative analysis revealed no observable
difference in dorsal column axonal loss between transplanted and control groups of
rats.
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Affiliation(s)
- Andrew Collins
- Spinal Repair Unit, Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, London, UK
| | - Ahmed Ibrahim
- Spinal Repair Unit, Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, London, UK
| | - Daqing Li
- Spinal Repair Unit, Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, London, UK
| | - Modinat Liadi
- Spinal Repair Unit, Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, London, UK
| | - Ying Li
- Spinal Repair Unit, Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, London, UK
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19
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Pioneer axons employ Cajal's battering ram to enter the spinal cord. Nat Commun 2019; 10:562. [PMID: 30718484 PMCID: PMC6362287 DOI: 10.1038/s41467-019-08421-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 01/09/2019] [Indexed: 01/17/2023] Open
Abstract
Sensory axons must traverse a spinal cord glia limitans to connect the brain with the periphery. The fundamental mechanism of how these axons enter the spinal cord is still debatable; both Ramon y Cajal’s battering ram hypothesis and a boundary cap model have been proposed. To distinguish between these hypotheses, we visualized the entry of pioneer axons into the dorsal root entry zone (DREZ) with time-lapse imaging in zebrafish. Here, we identify that DRG pioneer axons enter the DREZ before the arrival of neural crest cells at the DREZ. Instead, actin-rich invadopodia in the pioneer axon are necessary and sufficient for DREZ entry. Using photoactivable Rac1, we demonstrate cell-autonomous functioning of invasive structures in pioneer axon spinal entry. Together these data support the model that actin-rich invasion structures dynamically drive pioneer axon entry into the spinal cord, indicating that distinct pioneer and secondary events occur at the DREZ. The fundamental mechanism of how sensory axons traverse a spinal cord glia limitans remains debatable, with some suggesting a role for boundary cap cells at the dorsal root entry zone (DREZ). Here, authors use time-lapse imaging of DRG axons at the DREZ to show that pioneer axons enter the DREZ before the presence of boundary cap cells, and that this entry is critically dependent on the development of actin-rich invasion structures reminiscent of invadopodia.
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20
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Dupin E, Calloni GW, Coelho-Aguiar JM, Le Douarin NM. The issue of the multipotency of the neural crest cells. Dev Biol 2018; 444 Suppl 1:S47-S59. [DOI: 10.1016/j.ydbio.2018.03.024] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Revised: 03/29/2018] [Accepted: 03/30/2018] [Indexed: 12/25/2022]
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21
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Fontenas L, Kucenas S. Motor Exit Point (MEP) Glia: Novel Myelinating Glia That Bridge CNS and PNS Myelin. Front Cell Neurosci 2018; 12:333. [PMID: 30356886 PMCID: PMC6190867 DOI: 10.3389/fncel.2018.00333] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Accepted: 09/11/2018] [Indexed: 12/12/2022] Open
Abstract
Oligodendrocytes (OLs) and Schwann cells (SCs) have traditionally been thought of as the exclusive myelinating glial cells of the central and peripheral nervous systems (CNS and PNS), respectively, for a little over a century. However, recent studies demonstrate the existence of a novel, centrally-derived peripheral glial population called motor exit point (MEP) glia, which myelinate spinal motor root axons in the periphery. Until recently, the boundaries that exist between the CNS and PNS, and the cells permitted to cross them, were mostly described based on fixed histological collections and static lineage tracing. Recent work in zebrafish using in vivo, time-lapse imaging has shed light on glial cell interactions at the MEP transition zone and reveals a more complex picture of myelination both centrally and peripherally.
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Affiliation(s)
- Laura Fontenas
- Department of Biology, University of Virginia, Charlottesville, VA, United States
| | - Sarah Kucenas
- Department of Biology, University of Virginia, Charlottesville, VA, United States
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22
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Spruance VM, Zholudeva LV, Hormigo KM, Randelman ML, Bezdudnaya T, Marchenko V, Lane MA. Integration of Transplanted Neural Precursors with the Injured Cervical Spinal Cord. J Neurotrauma 2018; 35:1781-1799. [PMID: 29295654 PMCID: PMC6033309 DOI: 10.1089/neu.2017.5451] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Cervical spinal cord injuries (SCI) result in devastating functional consequences, including respiratory dysfunction. This is largely attributed to the disruption of phrenic pathways, which control the diaphragm. Recent work has identified spinal interneurons as possible contributors to respiratory neuroplasticity. The present work investigated whether transplantation of developing spinal cord tissue, inherently rich in interneuronal progenitors, could provide a population of new neurons and growth-permissive substrate to facilitate plasticity and formation of novel relay circuits to restore input to the partially denervated phrenic motor circuit. One week after a lateralized, C3/4 contusion injury, adult Sprague-Dawley rats received allografts of dissociated, developing spinal cord tissue (from rats at gestational days 13-14). Neuroanatomical tracing and terminal electrophysiology was performed on the graft recipients 1 month later. Experiments using pseudorabies virus (a retrograde, transynaptic tracer) revealed connections from donor neurons onto host phrenic circuitry and from host, cervical interneurons onto donor neurons. Anatomical characterization of donor neurons revealed phenotypic heterogeneity, though donor-host connectivity appeared selective. Despite the consistent presence of cholinergic interneurons within donor tissue, transneuronal tracing revealed minimal connectivity with host phrenic circuitry. Phrenic nerve recordings revealed changes in burst amplitude after application of a glutamatergic, but not serotonergic antagonist to the transplant, suggesting a degree of functional connectivity between donor neurons and host phrenic circuitry that is regulated by glutamatergic input. Importantly, however, anatomical and functional results were variable across animals, and future studies will explore ways to refine donor cell populations and entrain consistent connectivity.
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Affiliation(s)
- Victoria M Spruance
- Department of Neurobiology and Anatomy, Spinal Cord Research Center, Drexel University College of Medicine , Philadelphia, Pennsylvania
| | - Lyandysha V Zholudeva
- Department of Neurobiology and Anatomy, Spinal Cord Research Center, Drexel University College of Medicine , Philadelphia, Pennsylvania
| | - Kristiina M Hormigo
- Department of Neurobiology and Anatomy, Spinal Cord Research Center, Drexel University College of Medicine , Philadelphia, Pennsylvania
| | - Margo L Randelman
- Department of Neurobiology and Anatomy, Spinal Cord Research Center, Drexel University College of Medicine , Philadelphia, Pennsylvania
| | - Tatiana Bezdudnaya
- Department of Neurobiology and Anatomy, Spinal Cord Research Center, Drexel University College of Medicine , Philadelphia, Pennsylvania
| | - Vitaliy Marchenko
- Department of Neurobiology and Anatomy, Spinal Cord Research Center, Drexel University College of Medicine , Philadelphia, Pennsylvania
| | - Michael A Lane
- Department of Neurobiology and Anatomy, Spinal Cord Research Center, Drexel University College of Medicine , Philadelphia, Pennsylvania
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23
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Furlan A, Dyachuk V, Kastriti ME, Calvo-Enrique L, Abdo H, Hadjab S, Chontorotzea T, Akkuratova N, Usoskin D, Kamenev D, Petersen J, Sunadome K, Memic F, Marklund U, Fried K, Topilko P, Lallemend F, Kharchenko PV, Ernfors P, Adameyko I. Multipotent peripheral glial cells generate neuroendocrine cells of the adrenal medulla. Science 2018; 357:357/6346/eaal3753. [PMID: 28684471 DOI: 10.1126/science.aal3753] [Citation(s) in RCA: 208] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 06/05/2017] [Indexed: 12/23/2022]
Abstract
Adrenaline is a fundamental circulating hormone for bodily responses to internal and external stressors. Chromaffin cells of the adrenal medulla (AM) represent the main neuroendocrine adrenergic component and are believed to differentiate from neural crest cells. We demonstrate that large numbers of chromaffin cells arise from peripheral glial stem cells, termed Schwann cell precursors (SCPs). SCPs migrate along the visceral motor nerve to the vicinity of the forming adrenal gland, where they detach from the nerve and form postsynaptic neuroendocrine chromaffin cells. An intricate molecular logic drives two sequential phases of gene expression, one unique for a distinct transient cellular state and another for cell type specification. Subsequently, these programs down-regulate SCP-gene and up-regulate chromaffin cell-gene networks. The AM forms through limited cell expansion and requires the recruitment of numerous SCPs. Thus, peripheral nerves serve as a stem cell niche for neuroendocrine system development.
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Affiliation(s)
- Alessandro Furlan
- Unit of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Vyacheslav Dyachuk
- Department of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden.,National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, Vladivostok 690041, Russia.,Department of Nanophotonics and Metamaterials, ITMO University, St. Petersburg 197101, Russia
| | - Maria Eleni Kastriti
- Department of Physiology and Pharmacology, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Laura Calvo-Enrique
- Unit of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Hind Abdo
- Unit of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Saida Hadjab
- Department of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Tatiana Chontorotzea
- Department of Physiology and Pharmacology, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Natalia Akkuratova
- Skolkovo Institute of Science and Technology, Moscow 143005, Russia.,Institute of Translational Biomedicine, Saint Petersburg State University, St. Petersburg 199034, Russia
| | - Dmitry Usoskin
- Unit of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Dmitry Kamenev
- Department of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Julian Petersen
- Department of Physiology and Pharmacology, Karolinska Institutet, 17177 Stockholm, Sweden.,Center for Brain Research, Medical University Vienna, 1090 Vienna, Austria
| | - Kazunori Sunadome
- Department of Physiology and Pharmacology, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Fatima Memic
- Unit of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Ulrika Marklund
- Unit of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Kaj Fried
- Department of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Piotr Topilko
- Institut de Biologie de l'Ecole Normale Supérieure, Ecole Normale Supérieure, INSERM U1024, CNRS UMR 8197, 46 Rue d'Ulm, 75005 Paris, France
| | - Francois Lallemend
- Department of Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Peter V Kharchenko
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA 02115, USA
| | - Patrik Ernfors
- Unit of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177 Stockholm, Sweden.
| | - Igor Adameyko
- Department of Physiology and Pharmacology, Karolinska Institutet, 17177 Stockholm, Sweden. .,Center for Brain Research, Medical University Vienna, 1090 Vienna, Austria
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24
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Boundary cap cells in development and disease. Curr Opin Neurobiol 2017; 47:209-215. [DOI: 10.1016/j.conb.2017.11.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 10/10/2017] [Accepted: 11/03/2017] [Indexed: 01/18/2023]
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25
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Koeppen AH, Becker AB, Qian J, Gelman BB, Mazurkiewicz JE. Friedreich Ataxia: Developmental Failure of the Dorsal Root Entry Zone. J Neuropathol Exp Neurol 2017; 76:969-977. [PMID: 29044418 DOI: 10.1093/jnen/nlx087] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Dorsal root ganglia, dorsal roots (DR), and dorsal root entry zones (DREZ) are vulnerable to frataxin deficiency in Friedreich ataxia (FA). A previously unrecognized abnormality is the intrusion of astroglial tissue into DR. Segments of formalin-fixed upper lumbar spinal cord of 13 homozygous and 2 compound heterozygous FA patients were sectioned longitudinally to represent DREZ and stained for glial fibrillary acidic protein (GFAP), S100, vimentin, the central nervous system (CNS)-specific myelin protein proteolipid protein, the peripheral nervous system (PNS) myelin proteins PMP-22 and P0, and the Schwann cell proteins laminin, alpha-dystroglycan, and periaxin. Normal DREZ showed short, sharply demarcated, dome-like extensions of CNS tissue into DR. The Schwann cell-related proteins formed tight caps around these domes. In FA, GFAP-, S100-, and vimentin-reactive CNS tissue extended across DREZ and into DR over much longer distances by breaching the CNS-PNS barrier. The transition between PNS and CNS myelin proteins was disorganized. During development, neural-crest derived boundary cap cells provide guidance to dorsal root ganglia axons growing into the dorsal spinal cord and at the same time block the inappropriate intrusion of CNS glia into DR. It is likely that frataxin is required during a critical period of permissive (axons) and nonpermissive (astroglia) border-control.
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Affiliation(s)
- Arnulf H Koeppen
- Research Service, Veterans Affairs Medical Center, Albany, New York; Department of Pathology, Albany Medical College, Albany, New York; Department of Pathology and Laboratory Medicine, University of Texas Medical Branch, Galveston, Texas; Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York
| | - Alyssa B Becker
- Research Service, Veterans Affairs Medical Center, Albany, New York; Department of Pathology, Albany Medical College, Albany, New York; Department of Pathology and Laboratory Medicine, University of Texas Medical Branch, Galveston, Texas; Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York
| | - Jiang Qian
- Research Service, Veterans Affairs Medical Center, Albany, New York; Department of Pathology, Albany Medical College, Albany, New York; Department of Pathology and Laboratory Medicine, University of Texas Medical Branch, Galveston, Texas; Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York
| | - Benjamin B Gelman
- Research Service, Veterans Affairs Medical Center, Albany, New York; Department of Pathology, Albany Medical College, Albany, New York; Department of Pathology and Laboratory Medicine, University of Texas Medical Branch, Galveston, Texas; Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York
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26
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Livin' On The Edge: glia shape nervous system transition zones. Curr Opin Neurobiol 2017; 47:44-51. [PMID: 28957729 DOI: 10.1016/j.conb.2017.09.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 09/11/2017] [Indexed: 11/21/2022]
Abstract
The vertebrate nervous system is divided into two functional halves; the central nervous system (CNS), which includes the brain and spinal cord, and the peripheral nervous system (PNS), which consists of nerves and ganglia. Incoming peripheral stimuli transmitted from the periphery to the CNS and subsequent motor responses created because of this information, require efficient communication between the two halves that make up this organ system. Neurons and glial cells of each half of the nervous system, which are the main actors in this communication, segregate across nervous system transition zones and never mix, allowing for efficient neurotransmission. Studies aimed at understanding the cellular and molecular mechanisms governing the development and maintenance of these transition zones have predominantly focused on mammalian models. However, zebrafish has emerged as a powerful model organism to study these structures and has allowed researchers to identify novel glial cells and mechanisms essential for nervous system assembly. This review will highlight recent advances into the important role that glial cells play in building and maintaining the nervous system and its boundaries.
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27
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Smith CJ, Wheeler MA, Marjoram L, Bagnat M, Deppmann CD, Kucenas S. TNFa/TNFR2 signaling is required for glial ensheathment at the dorsal root entry zone. PLoS Genet 2017; 13:e1006712. [PMID: 28379965 PMCID: PMC5397050 DOI: 10.1371/journal.pgen.1006712] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 04/19/2017] [Accepted: 03/22/2017] [Indexed: 01/09/2023] Open
Abstract
Somatosensory information from the periphery is routed to the spinal cord through centrally-projecting sensory axons that cross into the central nervous system (CNS) via the dorsal root entry zone (DREZ). The glial cells that ensheath these axons ensure rapid propagation of this information. Despite the importance of this glial-axon arrangement, how this afferent nerve is assembled during development is unknown. Using in vivo, time-lapse imaging we show that as centrally-projecting pioneer axons from dorsal root ganglia (DRG) enter the spinal cord, they initiate expression of the cytokine TNFalpha. This induction coincides with ensheathment of these axons by associated glia via a TNF receptor 2 (TNFR2)-mediated process. This work identifies a signaling cascade that mediates peripheral glial-axon interactions and it functions to ensure that DRG afferent projections are ensheathed after pioneer axons complete their navigation, which promotes efficient somatosensory neural function.
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Affiliation(s)
- Cody J. Smith
- Department of Biology, University of Virginia, Charlottesville, Virginia, United States of America
| | - Michael A. Wheeler
- Neuroscience Graduate Program, University of Virginia, Charlottesville, Virginia, United States of America
| | - Lindsay Marjoram
- Department of Cell Biology, Duke University, Durham, North Carolina, United States of America
| | - Michel Bagnat
- Department of Cell Biology, Duke University, Durham, North Carolina, United States of America
| | - Christopher D. Deppmann
- Department of Biology, University of Virginia, Charlottesville, Virginia, United States of America
- Neuroscience Graduate Program, University of Virginia, Charlottesville, Virginia, United States of America
| | - Sarah Kucenas
- Department of Biology, University of Virginia, Charlottesville, Virginia, United States of America
- Neuroscience Graduate Program, University of Virginia, Charlottesville, Virginia, United States of America
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28
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Bai Z, Pu Q, Haque Z, Wang J, Huang R. The unique axon trajectory of the accessory nerve is determined by intrinsic properties of the neural tube in the avian embryo. Ann Anat 2016; 205:85-9. [PMID: 26955910 DOI: 10.1016/j.aanat.2016.02.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 02/10/2016] [Accepted: 02/20/2016] [Indexed: 11/26/2022]
Abstract
The accessory nerve is a cranial nerve, composed of only motor axons, which control neck muscles. Its axons ascend many segments along the lateral surface of the cervical spinal cord and hindbrain. At the level of the first somite, they pass ventrally through the somitic mesoderm into the periphery. The factors governing the unique root trajectory are unknown. Ablation experiments at the accessory nerve outlet points have shown that somites do not regulate the trajectory of the accessory nerve fibres. Factors from the neural tube that may control the longitudinal pathfinding of the accessory nerve fibres were tested by heterotopic transplantations of an occipital neural tube to the cervical and thoracic level. These transplantations resulted in a typical accessory nerve trajectory in the cervical and thoracic spinal cord. In contrast, cervical neural tube grafts were unable to give rise to the typical accessory nerve root pattern when transplanted to occipital level. Our results show that the formation of the unique axon root pattern of the accessory nerve is an intrinsic property of the neural tube.
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Affiliation(s)
- Zhongtian Bai
- The 2nd Department of General Surgery, the First Hospital of Lanzhou University, Key Laboratory of Biotherapy and Regenerative Medicine, Gansu Province, China; Department of Neuroanatomy, Institute of Anatomy, University of Bonn, Nussallee 10 53115, Bonn, Germany; Institute of Zoology, School of Life Science, Lanzhou University, China
| | - Qin Pu
- Department of Neuroanatomy, Institute of Anatomy, University of Bonn, Nussallee 10 53115, Bonn, Germany; Institute of Anatomy, Department of Anatomy and Molecular Embryology, Ruhr-University of Bochum, Bochum, Germany
| | - Ziaul Haque
- Department of Neuroanatomy, Institute of Anatomy, University of Bonn, Nussallee 10 53115, Bonn, Germany; Department of Anatomy and Histology, Bangladesh Agricultural University, Mymensingh, Bangladesh
| | - Jianlin Wang
- Institute of Zoology, School of Life Science, Lanzhou University, China
| | - Ruijin Huang
- Department of Neuroanatomy, Institute of Anatomy, University of Bonn, Nussallee 10 53115, Bonn, Germany; Department of Molecular Embryology, Institute of Anatomy and Cell Biology, University of Freiburg, Germany.
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Garrett AM, Jucius TJ, Sigaud LPR, Tang FL, Xiong WC, Ackerman SL, Burgess RW. Analysis of Expression Pattern and Genetic Deletion of Netrin5 in the Developing Mouse. Front Mol Neurosci 2016; 9:3. [PMID: 26858598 PMCID: PMC4726805 DOI: 10.3389/fnmol.2016.00003] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 01/07/2016] [Indexed: 11/13/2022] Open
Abstract
Boundary cap cells (BCC) are a transient, neural-crest-derived population found at the motor exit point (MEP) and dorsal root entry zone (DREZ) of the embryonic spinal cord. These cells contribute to the central/peripheral nervous system (CNS/PNS) boundary, and in their absence neurons and glia from the CNS migrate into the PNS. We found Netrin5 (Ntn5), a previously unstudied member of the netrin gene family, to be robustly expressed in BCC. We generated Ntn5 knockout mice and examined neurodevelopmental and BCC-related phenotypes. No abnormalities in cranial nerve guidance, dorsal root organization, or sensory projections were found. However, Ntn5 mutant embryos did have ectopic motor neurons (MNs) that migrated out of the ventral horn and into the motor roots. Previous studies have implicated semaphorin6A (Sema6A) in BCC signaling to plexinA2 (PlxnA2)/neuropilin2 (Nrp2) in MNs in restricting MN cell bodies to the ventral horn, particularly in the caudal spinal cord. In Ntn5 mutants, ectopic MNs are likely to be a different population, as more ectopias were found rostrally. Furthermore, ectopic MNs in Ntn5 mutants were not immunoreactive for NRP2. The netrin receptor deleted in colorectal cancer (DCC) is a potential receptor for NTN5 in MNs, as similar ectopic neurons were found in Dcc mutant mice, but not in mice deficient for other netrin receptors. Thus, Ntn5 is a novel netrin family member that is expressed in BCC, functioning to prevent MN migration out of the CNS.
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Affiliation(s)
| | | | | | - Fu-Lei Tang
- Department of Neuroscience and Regenerative Medicine, Department of Neurology, Medical College of Georgia, Georgia Regents University Augusta, GA, USA
| | - Wen-Cheng Xiong
- Department of Neuroscience and Regenerative Medicine, Department of Neurology, Medical College of Georgia, Georgia Regents University Augusta, GA, USA
| | - Susan L Ackerman
- The Jackson LaboratoryBar Harbor, ME, USA; Howard Hughes Medical InstituteChevy Chase, MD, USA
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Chemokine Signaling Controls Integrity of Radial Glial Scaffold in Developing Spinal Cord and Consequential Proper Position of Boundary Cap Cells. J Neurosci 2015; 35:9211-24. [PMID: 26085643 DOI: 10.1523/jneurosci.0156-15.2015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Radial glial cells are the neural progenitors of the developing CNS and have long radial processes that guide radially migrating neurons. The integrity of the radial glial scaffold, in particular proper adhesion between the endfeet of radial processes and the pial basement membrane (BM), is important for the cellular organization of the CNS, as indicated by evidence emerging from the developing cortex. However, the mechanisms underlying the maintenance of radial glial scaffold integrity during development, when the neuroepithelium rapidly expands, are still poorly understood. Here, we addressed this issue in the developing mouse spinal cord. We show that CXCR4, a receptor of chemokine CXCL12, is expressed in spinal cord radial glia. Conditional knock-out of Cxcr4 in radial glia caused disrupted radial glial scaffold with gaps at the pial endfeet layer and consequentially led to an invasion of boundary cap (BC) cells into the spinal cord. Because BC cells are PNS cells normally positioned at the incoming and outgoing axonal roots, their invasion into the spinal cord suggests a compromised CNS/PNS boundary in the absence of CXCL12/CXCR4 signaling. Both disrupted radial glial scaffold and invasion of BC cells into the CNS were also present in mice deficient in CXCR7, a second receptor of CXCL12. We further show that CXCL12 signaling promotes the radial glia adhesion to BM components and activates integrin β1 avidity. Our study unravels a novel molecular mechanism that deploys CXCL12/CXCR4/CXCR7 for the maintenance of radial glial scaffold integrity, which in turn safeguards the CNS/PNS boundary during spinal cord development.
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Squarzoni P, Thion MS, Garel S. Neuronal and microglial regulators of cortical wiring: usual and novel guideposts. Front Neurosci 2015; 9:248. [PMID: 26236185 PMCID: PMC4505395 DOI: 10.3389/fnins.2015.00248] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 06/30/2015] [Indexed: 12/17/2022] Open
Abstract
Neocortex functioning relies on the formation of complex networks that begin to be assembled during embryogenesis by highly stereotyped processes of cell migration and axonal navigation. The guidance of cells and axons is driven by extracellular cues, released along by final targets or intermediate targets located along specific pathways. In particular, guidepost cells, originally described in the grasshopper, are considered discrete, specialized cell populations located at crucial decision points along axonal trajectories that regulate tract formation. These cells are usually early-born, transient and act at short-range or via cell-cell contact. The vast majority of guidepost cells initially identified were glial cells, which play a role in the formation of important axonal tracts in the forebrain, such as the corpus callosum, anterior, and post-optic commissures as well as optic chiasm. In the last decades, tangential migrating neurons have also been found to participate in the guidance of principal axonal tracts in the forebrain. This is the case for several examples such as guideposts for the lateral olfactory tract (LOT), corridor cells, which open an internal path for thalamo-cortical axons and Cajal-Retzius cells that have been involved in the formation of the entorhino-hippocampal connections. More recently, microglia, the resident macrophages of the brain, were specifically observed at the crossroads of important neuronal migratory routes and axonal tract pathways during forebrain development. We furthermore found that microglia participate to the shaping of prenatal forebrain circuits, thereby opening novel perspectives on forebrain development and wiring. Here we will review the last findings on already known guidepost cell populations and will discuss the role of microglia as a potentially new class of atypical guidepost cells.
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Affiliation(s)
- Paola Squarzoni
- Centre National de la Recherche Scientifique UMR8197, Ecole Normale Supérieure, Institut de Biologie, Institut National de la Santé et de la Recherche Médicale U1024 Paris, France
| | - Morgane S Thion
- Centre National de la Recherche Scientifique UMR8197, Ecole Normale Supérieure, Institut de Biologie, Institut National de la Santé et de la Recherche Médicale U1024 Paris, France
| | - Sonia Garel
- Centre National de la Recherche Scientifique UMR8197, Ecole Normale Supérieure, Institut de Biologie, Institut National de la Santé et de la Recherche Médicale U1024 Paris, France
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Vidal M, Maniglier M, Deboux C, Bachelin C, Zujovic V, Baron-Van Evercooren A. Adult DRG Stem/Progenitor Cells Generate Pericytes in the Presence of Central Nervous System (CNS) Developmental Cues, and Schwann Cells in Response to CNS Demyelination. Stem Cells 2015; 33:2011-24. [DOI: 10.1002/stem.1997] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 01/30/2015] [Accepted: 02/10/2015] [Indexed: 12/15/2022]
Affiliation(s)
- Marie Vidal
- Inserm, U 1127; F-75013 Paris France
- CNRS, UMR 7225; F-75013 Paris France
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127; F-75013 Paris France
- Institut du Cerveau et de la Moelle épinière, ICM; F-75013 Paris France
| | - Madlyne Maniglier
- Inserm, U 1127; F-75013 Paris France
- CNRS, UMR 7225; F-75013 Paris France
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127; F-75013 Paris France
- Institut du Cerveau et de la Moelle épinière, ICM; F-75013 Paris France
| | - Cyrille Deboux
- Inserm, U 1127; F-75013 Paris France
- CNRS, UMR 7225; F-75013 Paris France
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127; F-75013 Paris France
- Institut du Cerveau et de la Moelle épinière, ICM; F-75013 Paris France
| | - Corinne Bachelin
- Inserm, U 1127; F-75013 Paris France
- CNRS, UMR 7225; F-75013 Paris France
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127; F-75013 Paris France
- Institut du Cerveau et de la Moelle épinière, ICM; F-75013 Paris France
| | - Violetta Zujovic
- Inserm, U 1127; F-75013 Paris France
- CNRS, UMR 7225; F-75013 Paris France
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127; F-75013 Paris France
- Institut du Cerveau et de la Moelle épinière, ICM; F-75013 Paris France
| | - Anne Baron-Van Evercooren
- Inserm, U 1127; F-75013 Paris France
- CNRS, UMR 7225; F-75013 Paris France
- Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127; F-75013 Paris France
- Institut du Cerveau et de la Moelle épinière, ICM; F-75013 Paris France
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Jacob C. Transcriptional control of neural crest specification into peripheral glia. Glia 2015; 63:1883-1896. [PMID: 25752517 DOI: 10.1002/glia.22816] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 01/29/2015] [Accepted: 02/20/2015] [Indexed: 12/20/2022]
Abstract
The neural crest is a transient migratory multipotent cell population that originates from the neural plate border and is formed at the end of gastrulation and during neurulation in vertebrate embryos. These cells give rise to many different cell types of the body such as chondrocytes, smooth muscle cells, endocrine cells, melanocytes, and cells of the peripheral nervous system including different subtypes of neurons and peripheral glia. Acquisition of lineage-specific markers occurs before or during migration and/or at final destination. What are the mechanisms that direct specification of neural crest cells into a specific lineage and how do neural crest cells decide on a specific migration route? Those are fascinating and complex questions that have existed for decades and are still in the research focus of developmental biologists. This review discusses transcriptional events and regulations occurring in neural crest cells and derived lineages, which control specification of peripheral glia, namely Schwann cell precursors that interact with peripheral axons and further differentiate into myelinating or nonmyelinating Schwann cells, satellite cells that remain tightly associated with neuronal cell bodies in sensory and autonomous ganglia, and olfactory ensheathing cells that wrap olfactory axons, both at the periphery in the olfactory mucosa and in the central nervous system in the olfactory bulb. Markers of the different peripheral glia lineages including intermediate multipotent cells such as boundary cap cells, as well as the functions of these specific markers, are also reviewed. Enteric ganglia, another type of peripheral glia, will not be discussed in this review. GLIA 2015;63:1883-1896.
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Affiliation(s)
- Claire Jacob
- Department of Biology, University of Fribourg, Fribourg, Switzerland
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Newbern JM. Molecular control of the neural crest and peripheral nervous system development. Curr Top Dev Biol 2015; 111:201-31. [PMID: 25662262 DOI: 10.1016/bs.ctdb.2014.11.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A transient and unique population of multipotent stem cells, known as neural crest cells (NCCs), generate a bewildering array of cell types during vertebrate development. An attractive model among developmental biologists, the study of NCC biology has provided a wealth of knowledge regarding the cellular and molecular mechanisms important for embryogenesis. Studies in numerous species have defined how distinct phases of NCC specification, proliferation, migration, and survival contribute to the formation of multiple functionally distinct organ systems. NCC contributions to the peripheral nervous system (PNS) are well known. Critical developmental processes have been defined that provide outstanding models for understanding how extracellular stimuli, cell-cell interactions, and transcriptional networks cooperate to direct cellular diversification and PNS morphogenesis. Dissecting the complex extracellular and intracellular mechanisms that mediate the formation of the PNS from NCCs may have important therapeutic implications for neurocristopathies, neuropathies, and certain forms of cancer.
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Affiliation(s)
- Jason M Newbern
- School of Life Sciences, Arizona State University, Tempe, Arizona, USA.
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35
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Yajima H, Suzuki M, Ochi H, Ikeda K, Sato S, Yamamura KI, Ogino H, Ueno N, Kawakami K. Six1 is a key regulator of the developmental and evolutionary architecture of sensory neurons in craniates. BMC Biol 2014; 12:40. [PMID: 24885223 PMCID: PMC4084797 DOI: 10.1186/1741-7007-12-40] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 05/22/2014] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Various senses and sensory nerve architectures of animals have evolved during adaptation to exploit diverse environments. In craniates, the trunk sensory system has evolved from simple mechanosensory neurons inside the spinal cord (intramedullary), called Rohon-Beard (RB) cells, to multimodal sensory neurons of dorsal root ganglia (DRG) outside the spinal cord (extramedullary). The fish and amphibian trunk sensory systems switch from RB cells to DRG during development, while amniotes rely exclusively on the DRG system. The mechanisms underlying the ontogenic switching and its link to phylogenetic transition remain unknown. RESULTS In Xenopus, Six1 overexpression promoted precocious apoptosis of RB cells and emergence of extramedullary sensory neurons, whereas Six1 knockdown delayed the reduction in RB cell number. Genetic ablation of Six1 and Six4 in mice led to the appearance of intramedullary sensory neuron-like cells as a result of medial migration of neural crest cells into the spinal cord and production of immature DRG neurons and fused DRG. Restoration of SIX1 expression in the neural crest-linage partially rescued the phenotype, indicating the cell autonomous requirements of SIX1 for normal extramedullary sensory neurogenesis. Mouse Six1 enhancer that mediates the expression in DRG neurons activated transcription in Xenopus RB cells earlier than endogenous six1 expression, suggesting earlier onset of mouse SIX1 expression than Xenopus during sensory development. CONCLUSIONS The results indicated the critical role of Six1 in transition of RB cells to DRG neurons during Xenopus development and establishment of exclusive DRG system of mice. The study provided evidence that early appearance of SIX1 expression, which correlated with mouse Six1 enhancer, is essential for the formation of DRG-dominant system in mice, suggesting that heterochronic changes in Six1 enhancer sequence play an important role in alteration of trunk sensory architecture and contribute to the evolution of the trunk sensory system.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Kiyoshi Kawakami
- Division of Biology, Center for Molecular Medicine, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan.
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Trolle C, Konig N, Abrahamsson N, Vasylovska S, Kozlova EN. Boundary cap neural crest stem cells homotopically implanted to the injured dorsal root transitional zone give rise to different types of neurons and glia in adult rodents. BMC Neurosci 2014; 15:60. [PMID: 24884373 PMCID: PMC4055944 DOI: 10.1186/1471-2202-15-60] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 04/24/2014] [Indexed: 01/08/2023] Open
Abstract
Background The boundary cap is a transient group of neural crest-derived cells located at the presumptive dorsal root transitional zone (DRTZ) when sensory axons enter the spinal cord during development. Later, these cells migrate to dorsal root ganglia and differentiate into subtypes of sensory neurons and glia. After birth when the DRTZ is established, sensory axons are no longer able to enter the spinal cord. Here we explored the fate of mouse boundary cap neural crest stem cells (bNCSCs) implanted to the injured DRTZ after dorsal root avulsion for their potential to assist sensory axon regeneration. Results Grafted cells showed extensive survival and differentiation after transplantation to the avulsed DRTZ. Transplanted cells located outside the spinal cord organized elongated tubes of Sox2/GFAP expressing cells closely associated with regenerating sensory axons or appeared as small clusters on the surface of the spinal cord. Other cells, migrating into the host spinal cord as single cells, differentiated to spinal cord neurons with different neurotransmitter characteristics, extensive fiber organization, and in some cases surrounded by glutamatergic terminal-like profiles. Conclusions These findings demonstrate that bNCSCs implanted at the site of dorsal root avulsion injury display remarkable differentiation plasticity inside the spinal cord and in the peripheral compartment where they organize tubes associated with regenerating sensory fibers. These properties offer a basis for exploring the ability of bNCSCs to assist regeneration of sensory axons into the spinal cord and replace lost neurons in the injured spinal cord.
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Affiliation(s)
| | | | | | | | - Elena N Kozlova
- Department of Neuroscience, Uppsala University Biomedical Center, Box 593, SE-751 24 Uppsala, Sweden.
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Kaiser A, Kale A, Novozhilova E, Siratirakun P, Aquino JB, Thonabulsombat C, Ernfors P, Olivius P. Brain stem slice conditioned medium contains endogenous BDNF and GDNF that affect neural crest boundary cap cells in co-culture. Brain Res 2014; 1566:12-23. [DOI: 10.1016/j.brainres.2014.04.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2013] [Revised: 03/17/2014] [Accepted: 04/07/2014] [Indexed: 01/14/2023]
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Kania A. Spinal motor neuron migration and the significance of topographic organization in the nervous system. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 800:133-48. [PMID: 24243104 DOI: 10.1007/978-94-007-7687-6_8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The nervous system displays a high degree of topographic organisation such that neuronal soma position is closely correlated to axonal trajectory. One example of such order is the myotopic organisation of the motor system where spinal motor neuron position parallels that of target muscles. This chapter will discuss the molecular mechanisms underlying motor neuron soma positioning, which include transcriptional control of Reelin signaling and cadherin expression. As the same transcription factors have been shown to control motor axon innervation of target muscles, a simple mechanism of topographic organisation specification is becoming evident raising the question of how coordinating soma position with axon trajectory might be important for nervous system wiring and its function.
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Affiliation(s)
- Artur Kania
- Institut de recherches cliniques de Montréal (IRCM), 110, ave. des Pins Ouest, Montréal, QC, H2W 1R7, Canada,
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East E, Johns N, Georgiou M, Golding JP, Loughlin AJ, Kingham PJ, Phillips JB. A 3D in vitro model reveals differences in the astrocyte response elicited by potential stem cell therapies for CNS injury. Regen Med 2013; 8:739-46. [PMID: 24147529 PMCID: PMC3831573 DOI: 10.2217/rme.13.61] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
AIM This study aimed to develop a 3D culture model to test the extent to which transplanted stem cells modulate astrocyte reactivity, where exacerbated glial cell activation could be detrimental to CNS repair success. MATERIALS & METHODS The reactivity of rat astrocytes to bone marrow mesenchymal stem cells, neural crest stem cells (NCSCs) and differentiated adipose-derived stem cells was assessed after 5 days. Schwann cells were used as a positive control. RESULTS NCSCs and differentiated Schwann cell-like adipose-derived stem cells did not increase astrocyte reactivity. Highly reactive responses to bone marrow mesenchymal stem cells and Schwann cells were equivalent. CONCLUSION This approach can screen therapeutic cells prior to in vivo testing, allowing cells likely to trigger a substantial astrocyte response to be identified at an early stage. NCSCs and differentiated Schwann cell-like adipose-derived stem cells may be useful in treating CNS damage without increasing astrogliosis.
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Affiliation(s)
- Emma East
- Department of Life Health & Chemical Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK
| | - Noémie Johns
- Department of Life Health & Chemical Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK
| | - Melanie Georgiou
- Department of Life Health & Chemical Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK
| | - Jon P Golding
- Department of Life Health & Chemical Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK
| | - A Jane Loughlin
- Department of Life Health & Chemical Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK
| | - Paul J Kingham
- Department of Integrative Medical Biology, Umeå University, SE 901 87, Umeå, Sweden
| | - James B Phillips
- Department of Life Health & Chemical Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK
- Department of Biomaterials & Tissue Engineering, UCL Eastman Dental Institute, 256 Gray’s Inn Road, London WC1X 8LD, UK
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40
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East E, Golding JP, Phillips JB. Engineering an integrated cellular interface in three-dimensional hydrogel cultures permits monitoring of reciprocal astrocyte and neuronal responses. Tissue Eng Part C Methods 2012; 18:526-36. [PMID: 22235832 PMCID: PMC3381295 DOI: 10.1089/ten.tec.2011.0587] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Accepted: 01/09/2012] [Indexed: 11/12/2022] Open
Abstract
This study reports a new type of three-dimensional (3D) tissue model for studying interactions between cell types in collagen hydrogels. The aim was to create a 3D cell culture model containing separate cell populations in close proximity without the presence of a mechanical barrier, and demonstrate its relevance to modeling the axon growth-inhibitory cellular interfaces that develop in the central nervous system (CNS) in response to damage. This provides a powerful new tool to determine which aspects of the astroglial scar response and subsequent neuronal regeneration inhibition are determined by the presence of the other cell types. Astrocytes (CNS glia) and dissociated dorsal root ganglia (DRG; containing neurons and peripheral nervous system [PNS] glia) were seeded within collagen solution at 4 °C in adjacent chambers of a stainless steel mould, using cells cultured from wild-type or green fluorescent protein expressing rats, to track specific populations. The divider between the chambers was removed using a protocol that allowed the gels to integrate without mixing of the cell populations. Following setting of the gels, they were maintained in culture for up to 15 days. Reciprocal astrocyte and neuronal responses were monitored using confocal microscopy and 3D image analysis. At DRG:astrocyte interfaces, by 5 days there was an increase in the number of astrocytes at the interface followed by hypertrophy and increased glial fibrillary acidic protein expression at 10 and 15 days, indicative of reactive gliosis. Neurons avoided crossing DRG:astrocyte interfaces, and neuronal growth was restricted to the DRG part of the gel. By contrast, neurons were able to grow freely across DRG:DRG interfaces, demonstrating the absence of a mechanical barrier. These results show that in a precisely controlled 3D environment, an interface between DRG and astrocyte cultures is sufficient to trigger reactive gliosis and inhibition of neuronal regeneration across the interface. Different aspects of the astrocyte response could be independently monitored, providing an insight into the formation of a glial scar. This technology has wide potential for researchers wishing to maintain and monitor interactions between adjacent cell populations in 3D culture.
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Affiliation(s)
- Emma East
- Faculty of Science, The Open University, Milton Keynes, United Kingdom
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McGraw HF, Snelson CD, Prendergast A, Suli A, Raible DW. Postembryonic neuronal addition in zebrafish dorsal root ganglia is regulated by Notch signaling. Neural Dev 2012; 7:23. [PMID: 22738203 PMCID: PMC3438120 DOI: 10.1186/1749-8104-7-23] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2012] [Accepted: 05/11/2012] [Indexed: 12/25/2022] Open
Abstract
Background The sensory neurons and glia of the dorsal root ganglia (DRG) arise from neural crest cells in the developing vertebrate embryo. In mouse and chick, DRG formation is completed during embryogenesis. In contrast, zebrafish continue to add neurons and glia to the DRG into adulthood, long after neural crest migration is complete. The molecular and cellular regulation of late DRG growth in the zebrafish remains to be characterized. Results In the present study, we use transgenic zebrafish lines to examine neuronal addition during postembryonic DRG growth. Neuronal addition is continuous over the period of larval development. Fate-mapping experiments support the hypothesis that new neurons are added from a population of resident, neural crest-derived progenitor cells. Conditional inhibition of Notch signaling was used to assess the role of this signaling pathway in neuronal addition. An increase in the number of DRG neurons is seen when Notch signaling is inhibited during both early and late larval development. Conclusions Postembryonic growth of the zebrafish DRG comes about, in part, by addition of new neurons from a resident progenitor population, a process regulated by Notch signaling.
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Affiliation(s)
- Hillary Faye McGraw
- Molecular and Cellular Biology Program, University of Washington, 1959 NE Pacific St, Seattle, WA 98195, USA
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Crossing the border: molecular control of motor axon exit. Int J Mol Sci 2011; 12:8539-61. [PMID: 22272090 PMCID: PMC3257087 DOI: 10.3390/ijms12128539] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Revised: 11/05/2011] [Accepted: 11/08/2011] [Indexed: 11/23/2022] Open
Abstract
Living organisms heavily rely on the function of motor circuits for their survival and for adapting to ever-changing environments. Unique among central nervous system (CNS) neurons, motor neurons (MNs) project their axons out of the CNS. Once in the periphery, motor axons navigate along highly stereotyped trajectories, often at considerable distances from their cell bodies, to innervate appropriate muscle targets. A key decision made by pathfinding motor axons is whether to exit the CNS through dorsal or ventral motor exit points (MEPs). In contrast to the major advances made in understanding the mechanisms that regulate the specification of MN subtypes and the innervation of limb muscles, remarkably little is known about how MN axons project out of the CNS. Nevertheless, a limited number of studies, mainly in Drosophila, have identified transcription factors, and in some cases candidate downstream effector molecules, that are required for motor axons to exit the spinal cord. Notably, specialized neural crest cell derivatives, referred to as Boundary Cap (BC) cells, pre-figure and demarcate MEPs in vertebrates. Surprisingly, however, BC cells are not required for MN axon exit, but rather restrict MN cell bodies from ectopically migrating along their axons out of the CNS. Here, we describe the small set of studies that have addressed motor axon exit in Drosophila and vertebrates, and discuss our fragmentary knowledge of the mechanisms, which guide motor axons out of the CNS.
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Boundary cap cells are peripheral nervous system stem cells that can be redirected into central nervous system lineages. Proc Natl Acad Sci U S A 2011; 108:10714-9. [PMID: 21670295 DOI: 10.1073/pnas.1018687108] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Boundary cap cells (BC), which express the transcription factor Krox20, participate in the formation of the boundary between the central nervous system and the peripheral nervous system. To study BC stemness, we developed a method to purify and amplify BC in vitro from Krox20(Cre/+), R26R(YFP/+) mouse embryos. We show that BC progeny are EGF/FGF2-responsive, form spheres, and express neural crest markers. Upon growth factor withdrawal, BC progeny gave rise to multiple neural crest and CNS lineages. Transplanted into the developing murine forebrain, they successfully survived, migrated, and integrated within the host environment. Surprisingly, BC progeny generated exclusively CNS cells, including neurons, astrocytes, and myelin-forming oligodendrocytes. In vitro experiments indicated that a sequential combination of ventralizing morphogens and glial growth factors was necessary to reprogram BC into oligodendrocytes. Thus, BC progeny are endowed with differentiation plasticity beyond the peripheral nervous system. The demonstration that CNS developmental cues can reprogram neural crest-derived stem cells into CNS derivatives suggests that BC could serve as a source of cell type-specific lineages, including oligodendrocytes, for cell-based therapies to treat CNS disorders.
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44
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East E, de Oliveira DB, Golding JP, Phillips JB. Alignment of astrocytes increases neuronal growth in three-dimensional collagen gels and is maintained following plastic compression to form a spinal cord repair conduit. Tissue Eng Part A 2011; 16:3173-84. [PMID: 20649441 DOI: 10.1089/ten.tea.2010.0017] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
After injury to the spinal cord, reactive astrocytes form a glial scar consisting of highly ramified cell processes that constitute a major impediment to repair, partly due to their lack of orientation and guidance for regenerating axons. In some nonmammalian vertebrates, successful central nervous system regeneration is attributed to the alignment of reactive glia, which guide axons across the lesion site. Here, a three-dimensional mammalian cell-seeded collagen gel culture system was used to explore the effect of astrocyte alignment on neuronal growth. Astrocyte alignment was mapped within tethered rectangular gels and was significantly greater at the edge and middle of the gels compared to the control unaligned regions. When neurons were seeded on and within astrocyte gels, neurite length was greatest in the areas of astrocyte alignment. There was no difference in expression of astrocyte reactivity markers between aligned and control areas. Having established the potential utility of astrocyte alignment, the aligned gels were plastic compressed, transforming them into mechanically robust implantable devices. After compression, astrocytes remained viable and aligned and supported neurite outgrowth, yielding a novel method for assembling aligned cellular constructs suitable for tissue engineering and highlighting the importance of astrocyte alignment as a possible future therapeutic intervention for spinal cord repair.
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Affiliation(s)
- Emma East
- Department of Life Sciences, The Open University, Walton Hall, Milton Keynes, United Kingdom.
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45
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Abstract
Dorsal root ganglion (DRG) sensory neurons transmit all somatosensory information from the trunk region of the body. erbb3 mutant zebrafish do not form DRG neurons because the neural crest cells that generate them migrate aberrantly. Here we report that homozygous erbb3 mutants appear to swim and feed normally, and that they survive through adulthood, despite never forming DRG neurons. The source of sensory compensation in adult erbb3 mutants remains unknown, although it may be from lateral line ganglion neuromasts which are reduced, but present, in erbb3 mutants. We also provide new information about the development of DRG neurons in wild-type juvenile zebrafish.
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Affiliation(s)
- Yasuko Honjo
- Institute of Neuroscience, University of Oregon, Eugene, OR, USA.
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46
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Kucenas S, Wang WD, Knapik EW, Appel B. A selective glial barrier at motor axon exit points prevents oligodendrocyte migration from the spinal cord. J Neurosci 2009; 29:15187-94. [PMID: 19955371 PMCID: PMC2837368 DOI: 10.1523/jneurosci.4193-09.2009] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2009] [Revised: 10/09/2009] [Accepted: 10/19/2009] [Indexed: 11/21/2022] Open
Abstract
Nerve roots have specialized transition zones that permit axon extension but limit cell movement between the CNS and PNS. Boundary cap cells prevent motor neuron soma from following their axons into the periphery, thereby contributing to a selective barrier. Transition zones also restrict movement of glial cells. Consequently, axons that cross the CNS-PNS interface are insulated by central and peripheral myelin. The mechanisms that prevent the migratory progenitors of oligodendrocytes and Schwann cells, the myelinating cells of the CNS and PNS, respectively, from crossing transition zones are not known. Here, we show that interactions between myelinating glial cells prevent their movements across the interface. Using in vivo time-lapse imaging in zebrafish we found that, in the absence of Schwann cells, oligodendrocyte progenitors cross ventral root transition zones and myelinate motor axons. These studies reveal that distinct mechanisms regulate the movement of axons, neurons, and glial cells across the CNS-PNS interface.
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Affiliation(s)
- Sarah Kucenas
- Department of Biological Sciences
- Vanderbilt Program in Developmental Biology, and
| | - Wen-Der Wang
- Vanderbilt Program in Developmental Biology, and
- Division of Genetic Medicine, Vanderbilt University, Nashville, Tennessee, 37235, and
| | - Ela W. Knapik
- Vanderbilt Program in Developmental Biology, and
- Division of Genetic Medicine, Vanderbilt University, Nashville, Tennessee, 37235, and
| | - Bruce Appel
- Department of Biological Sciences
- Department of Pediatrics, University of Colorado Denver–Anschutz Medical Campus, Aurora, Colorado 80045
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47
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Coulpier F, Le Crom S, Maro GS, Manent J, Giovannini M, Maciorowski Z, Fischer A, Gessler M, Charnay P, Topilko P. Novel features of boundary cap cells revealed by the analysis of newly identified molecular markers. Glia 2009; 57:1450-7. [DOI: 10.1002/glia.20862] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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48
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Abstract
The ensheathment of neurons and their axons creates an ion-sensitive microenvironment that allows rapid conduction of nerve impulses. One of the fundamental questions about axonal ensheathment is how insulating glial cells wrap around axons. The mechanisms that underlie insulation of axons in invertebrates and vertebrates are not fully understood. In the present article we address cellular aspects of axonal ensheathment in Drosophila by taking advantage of glial mutants that illustrate a range of phenotypic defects including ensheathment of axons. From the findings of these mutant studies, we summarize that loss of glial cells, defects in glial membrane wrapping, failure of glial migration, and loss of specialized ladderlike septate junctions between ensheathing glial membranes result in axon-glial functional defects. These studies provide a broad perspective on glial ensheathment of axons in Drosophila and key insights into the anatomical and cellular aspects of axonal insulation. Given the powerful genetic approaches available in Drosophila, the axonal ensheathment process can be dissected in great detail to reveal the fundamental principles of ensheathment. These observations will be relevant to understanding the very similar processes in vertebrates, where defects in glial cell functions lead to devastating neurological diseases.
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Affiliation(s)
- Swati Banerjee
- Department of Cell and Molecular Physiology, Neurodevelopmental Disorders Research Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7545, USA
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49
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Abstract
In the spinal cord, developing motor neurons extend their axons into the periphery while their cell bodies remain within the motor columns in the spinal cord. Two recent papers show that this partitioning involves forward and reverse semaphorin-plexin signaling between motor neurons and neural crest boundary cap cells.
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Affiliation(s)
- Sophie Chauvet
- CNRS UMR 6216, Université de la Méditerranée, Developmental Biology Institute of Marseille Luminy, Case 907 Parc Scientifique de Luminy, 13288 Marseille cedex 09, France
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50
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Topilko P, Maro G, Charnay P. [Boundary caps: a gating function at the CNS/PNS interface and a source of pluripotent PNS cells]. Rev Neurol (Paris) 2008; 163:1252-5. [PMID: 18355477 DOI: 10.1016/s0035-3787(07)78414-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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