1
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Hong J, Garfolo R, Kabre S, Humml C, Velanac V, Roué C, Beck B, Jeanette H, Haslam S, Bach M, Arora S, Acheta J, Nave KA, Schwab MH, Jourd’heuil D, Poitelon Y, Belin S. PMP2 regulates myelin thickening and ATP production during remyelination. Glia 2024; 72:885-898. [PMID: 38311982 PMCID: PMC11027087 DOI: 10.1002/glia.24508] [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: 09/14/2023] [Revised: 12/22/2023] [Accepted: 01/16/2024] [Indexed: 02/06/2024]
Abstract
It is well established that axonal Neuregulin 1 type 3 (NRG1t3) regulates developmental myelin formation as well as EGR2-dependent gene activation and lipid synthesis. However, in peripheral neuropathy disease context, elevated axonal NRG1t3 improves remyelination and myelin sheath thickness without increasing Egr2 expression or activity, and without affecting the transcriptional activity of canonical myelination genes. Surprisingly, Pmp2, encoding for a myelin fatty acid binding protein, is the only gene whose expression increases in Schwann cells following overexpression of axonal NRG1t3. Here, we demonstrate PMP2 expression is directly regulated by NRG1t3 active form, following proteolytic cleavage. Then, using a transgenic mouse model overexpressing axonal NRG1t3 (NRG1t3OE) and knocked out for PMP2, we demonstrate that PMP2 is required for NRG1t3-mediated remyelination. We demonstrate that the sustained expression of Pmp2 in NRG1t3OE mice enhances the fatty acid uptake in sciatic nerve fibers and the mitochondrial ATP production in Schwann cells. In sum, our findings demonstrate that PMP2 is a direct downstream mediator of NRG1t3 and that the modulation of PMP2 downstream NRG1t3 activation has distinct effects on Schwann cell function during developmental myelination and remyelination.
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Affiliation(s)
- Jiayue Hong
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York, USA
| | - Rebekah Garfolo
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York, USA
| | - Sejal Kabre
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York, USA
| | - Christian Humml
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Viktorija Velanac
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Clémence Roué
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York, USA
| | - Brianna Beck
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York, USA
| | - Haley Jeanette
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York, USA
| | - Sarah Haslam
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York, USA
| | - Martin Bach
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York, USA
| | - Simar Arora
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York, USA
| | - Jenica Acheta
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York, USA
| | - Klaus-Armin Nave
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Markus H. Schwab
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Paul Flechsig Institute of Neuropathology, University Hospital Leipzig, Leipzig, Germany
| | - David Jourd’heuil
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, New York, USA
| | - Yannick Poitelon
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York, USA
| | - Sophie Belin
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York, USA
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2
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Grove M, Kim H, Pang S, Amaya JP, Hu G, Zhou J, Lemay M, Son YJ. TEAD1 is crucial for developmental myelination, Remak bundles, and functional regeneration of peripheral nerves. eLife 2024; 13:e87394. [PMID: 38456457 PMCID: PMC10959528 DOI: 10.7554/elife.87394] [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: 03/15/2023] [Accepted: 03/06/2024] [Indexed: 03/09/2024] Open
Abstract
Previously we showed that the hippo pathway transcriptional effectors, YAP and TAZ, are essential for Schwann cells (SCs) to develop, maintain and regenerate myelin . Although TEAD1 has been implicated as a partner transcription factor, the mechanisms by which it mediates YAP/TAZ regulation of SC myelination are unclear. Here, using conditional and inducible knockout mice, we show that TEAD1 is crucial for SCs to develop and regenerate myelin. It promotes myelination by both positively and negatively regulating SC proliferation, enabling Krox20/Egr2 to upregulate myelin proteins, and upregulating the cholesterol biosynthetic enzymes FDPS and IDI1. We also show stage-dependent redundancy of TEAD1 and that non-myelinating SCs have a unique requirement for TEAD1 to enwrap nociceptive axons in Remak bundles. Our findings establish TEAD1 as a major partner of YAP/TAZ in developmental myelination and functional nerve regeneration and as a novel transcription factor regulating Remak bundle integrity.
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Affiliation(s)
- Matthew Grove
- Department of Neural Sciences, Shriners Hospitals Pediatric Research Center, Lewis Katz School of Medicine, Temple UniversityPhiladelphiaUnited States
| | - Hyukmin Kim
- Department of Neural Sciences, Shriners Hospitals Pediatric Research Center, Lewis Katz School of Medicine, Temple UniversityPhiladelphiaUnited States
| | - Shuhuan Pang
- Department of Neural Sciences, Shriners Hospitals Pediatric Research Center, Lewis Katz School of Medicine, Temple UniversityPhiladelphiaUnited States
| | - Jose Paz Amaya
- Department of Bioengineering, Temple UniversityPhiladelphiaUnited States
| | - Guoqing Hu
- Department of Pharmacology & Toxicology, Medical College of Georgia, Augusta UniversityAugustaUnited States
| | - Jiliang Zhou
- Department of Pharmacology & Toxicology, Medical College of Georgia, Augusta UniversityAugustaUnited States
| | - Michel Lemay
- Department of Bioengineering, Temple UniversityPhiladelphiaUnited States
| | - Young-Jin Son
- Department of Neural Sciences, Shriners Hospitals Pediatric Research Center, Lewis Katz School of Medicine, Temple UniversityPhiladelphiaUnited States
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3
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Trimarco A, Audano M, Marca RL, Cariello M, Falco M, Pedretti S, Imperato G, Cestaro A, Podini P, Dina G, Quattrini A, Massimino L, Caruso D, Mitro N, Taveggia C. Prostaglandin D2 synthase controls Schwann cells metabolism. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.29.582775. [PMID: 38496560 PMCID: PMC10942270 DOI: 10.1101/2024.02.29.582775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
We previously reported that in the absence of Prostaglandin D2 synthase (L-PGDS) peripheral nerves are hypomyelinated in development and that with aging they present aberrant myelin sheaths. We now demonstrate that L-PGDS expressed in Schwann cells is part of a coordinated program aiming at preserving myelin integrity. In vivo and in vitro lipidomic, metabolomic and transcriptomic analyses confirmed that myelin lipids composition, Schwann cells energetic metabolism and key enzymes controlling these processes are altered in the absence of L-PGDS. Moreover, Schwann cells undergo a metabolic rewiring and turn to acetate as the main energetic source. Further, they produce ketone bodies to ensure glial cell and neuronal survival. Importantly, we demonstrate that all these changes correlate with morphological myelin alterations and describe the first physiological pathway implicated in preserving PNS myelin. Collectively, we posit that myelin lipids serve as a reservoir to provide ketone bodies, which together with acetate represent the adaptive substrates Schwann cells can rely on to sustain the axo-glial unit and preserve the integrity of the PNS.
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4
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Heller DT, Kolson DR, Brandebura AN, Amick EM, Wan J, Ramadan J, Holcomb PS, Liu S, Deerinck TJ, Ellisman MH, Qian J, Mathers PH, Spirou GA. Astrocyte ensheathment of calyx-forming axons of the auditory brainstem precedes accelerated expression of myelin genes and myelination by oligodendrocytes. J Comp Neurol 2024; 532:e25552. [PMID: 37916792 PMCID: PMC10922096 DOI: 10.1002/cne.25552] [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: 02/28/2023] [Revised: 09/22/2023] [Accepted: 10/17/2023] [Indexed: 11/03/2023]
Abstract
Early postnatal brain development involves complex interactions among maturing neurons and glial cells that drive tissue organization. We previously analyzed gene expression in tissue from the mouse medial nucleus of the trapezoid body (MNTB) during the first postnatal week to study changes that surround rapid growth of the large calyx of Held (CH) nerve terminal. Here, we present genes that show significant changes in gene expression level during the second postnatal week, a developmental timeframe that brackets the onset of airborne sound stimulation and the early stages of myelination. Gene Ontology analysis revealed that many of these genes are related to the myelination process. Further investigation of these genes using a previously published cell type-specific bulk RNA-Seq data set in cortex and our own single-cell RNA-Seq data set in the MNTB revealed enrichment of these genes in the oligodendrocyte lineage (OL) cells. Combining the postnatal day (P)6-P14 microarray gene expression data with the previously published P0-P6 data provided fine temporal resolution to investigate the initiation and subsequent waves of gene expression related to OL cell maturation and the process of myelination. Many genes showed increasing expression levels between P2 and P6 in patterns that reflect OL cell maturation. Correspondingly, the first myelin proteins were detected by P4. Using a complementary, developmental series of electron microscopy 3D image volumes, we analyzed the temporal progression of axon wrapping and myelination in the MNTB. By employing a combination of established ultrastructural criteria to classify reconstructed early postnatal glial cells in the 3D volumes, we demonstrated for the first time that astrocytes within the mouse MNTB extensively wrap the axons of the growing CH terminal prior to OL cell wrapping and compaction of myelin. Our data revealed significant expression of several myelin genes and enrichment of multiple genes associated with lipid metabolism in astrocytes, which may subserve axon wrapping in addition to myelin formation. The transition from axon wrapping by astrocytes to OL cells occurs rapidly between P4 and P9 and identifies a potential new role of astrocytes in priming calyceal axons for subsequent myelination.
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Affiliation(s)
| | - Douglas R. Kolson
- WVU Rockefeller Neuroscience Institute, West Virginia University School of Medicine, Morgantown, WV
- Otolaryngology HNS, West Virginia University School of Medicine, Morgantown, WV
| | - Ashley N. Brandebura
- WVU Rockefeller Neuroscience Institute, West Virginia University School of Medicine, Morgantown, WV
- Biochemistry, West Virginia University School of Medicine, Morgantown, WV
| | - Emily M. Amick
- Medical Engineering, University of South Florida, Tampa, FL
| | - Jun Wan
- Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN
| | - Jad Ramadan
- Otolaryngology HNS, West Virginia University School of Medicine, Morgantown, WV
| | - Paul S. Holcomb
- WVU Rockefeller Neuroscience Institute, West Virginia University School of Medicine, Morgantown, WV
| | - Sheng Liu
- Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN
| | - Thomas J. Deerinck
- National Center for Microscopy and Imaging Research, University of California, San Diego, CA
- Department of Neuroscience, University of California, San Diego, CA
| | - Mark H. Ellisman
- National Center for Microscopy and Imaging Research, University of California, San Diego, CA
- Department of Neuroscience, University of California, San Diego, CA
| | - Jiang Qian
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Peter H. Mathers
- WVU Rockefeller Neuroscience Institute, West Virginia University School of Medicine, Morgantown, WV
- Otolaryngology HNS, West Virginia University School of Medicine, Morgantown, WV
- Biochemistry, West Virginia University School of Medicine, Morgantown, WV
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5
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Grove M, Kim H, Pang S, Amaya JP, Hu G, Zhou J, Lemay M, Son YJ. TEAD1 is crucial for developmental myelination, Remak bundles, and functional regeneration of peripheral nerves. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.02.27.530298. [PMID: 38293102 PMCID: PMC10827063 DOI: 10.1101/2023.02.27.530298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
Previously we showed that the hippo pathway transcriptional effectors, YAP and TAZ, are essential for Schwann cells (SCs) to develop, maintain and regenerate myelin (Grove et al., 2017; Grove, Lee, Zhao, & Son, 2020). Although TEAD1 has been implicated as a partner transcription factor, the mechanisms by which it mediates YAP/TAZ regulation of SC myelination are unclear. Here, using conditional and inducible knockout mice, we show that TEAD1 is crucial for SCs to develop and regenerate myelin. It promotes myelination by both positively and negatively regulating SC proliferation, enabling Krox20/Egr2 to upregulate myelin proteins, and upregulating the cholesterol biosynthetic enzymes FDPS and IDI1. We also show stage-dependent redundancy of TEAD1 and that non-myelinating SCs have a unique requirement for TEAD1 to enwrap nociceptive axons in Remak bundles. Our findings establish TEAD1 as a major partner of YAP/TAZ in developmental myelination and functional nerve regeneration and as a novel transcription factor regulating Remak bundle integrity.
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6
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Cescon M, Gambarotta G, Calabrò S, Cicconetti C, Anselmi F, Kankowski S, Lang L, Basic M, Bleich A, Bolsega S, Steglich M, Oliviero S, Raimondo S, Bizzotto D, Haastert-Talini K, Ronchi G. Gut microbiota depletion delays somatic peripheral nerve development and impairs neuromuscular junction maturation. Gut Microbes 2024; 16:2363015. [PMID: 38845453 PMCID: PMC11164225 DOI: 10.1080/19490976.2024.2363015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 05/29/2024] [Indexed: 06/12/2024] Open
Abstract
Gut microbiota is responsible for essential functions in human health. Several communication axes between gut microbiota and other organs via neural, endocrine, and immune pathways have been described, and perturbation of gut microbiota composition has been implicated in the onset and progression of an emerging number of diseases. Here, we analyzed peripheral nerves, dorsal root ganglia (DRG), and skeletal muscles of neonatal and young adult mice with the following gut microbiota status: a) germ-free (GF), b) gnotobiotic, selectively colonized with 12 specific gut bacterial strains (Oligo-Mouse-Microbiota, OMM12), or c) natural complex gut microbiota (CGM). Stereological and morphometric analyses revealed that the absence of gut microbiota impairs the development of somatic median nerves, resulting in smaller diameter and hypermyelinated axons, as well as in smaller unmyelinated fibers. Accordingly, DRG and sciatic nerve transcriptomic analyses highlighted a panel of differentially expressed developmental and myelination genes. Interestingly, the type III isoform of Neuregulin1 (NRG1), known to be a neuronal signal essential for Schwann cell myelination, was overexpressed in young adult GF mice, with consequent overexpression of the transcription factor Early Growth Response 2 (Egr2), a fundamental gene expressed by Schwann cells at the onset of myelination. Finally, GF status resulted in histologically atrophic skeletal muscles, impaired formation of neuromuscular junctions, and deregulated expression of related genes. In conclusion, we demonstrate for the first time a gut microbiota regulatory impact on proper development of the somatic peripheral nervous system and its functional connection to skeletal muscles, thus suggesting the existence of a novel 'Gut Microbiota-Peripheral Nervous System-axis.'
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Affiliation(s)
- Matilde Cescon
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Giovanna Gambarotta
- Department of Clinical and Biological Sciences & Neuroscience Institute Cavalieri Ottolenghi (NICO), University of Torino, Orbassano, Italy
| | - Sonia Calabrò
- Department of Molecular Medicine, University of Padova, Padova, Italy
- Department of Biology, University of Padova, Padova, Italy
| | - Chiara Cicconetti
- Department of Life Sciences and Systems Biology, University of Torino, Torino, Italy
| | - Francesca Anselmi
- Department of Life Sciences and Systems Biology, University of Torino, Torino, Italy
| | - Svenja Kankowski
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Lower-Saxony, Germany
| | - Luisa Lang
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Lower-Saxony, Germany
| | - Marijana Basic
- Institute for Laboratory Animal Science and Central Animal Facility, Hannover Medical School, Hannover, Lower-Saxony, Germany
| | - Andre Bleich
- Institute for Laboratory Animal Science and Central Animal Facility, Hannover Medical School, Hannover, Lower-Saxony, Germany
| | - Silvia Bolsega
- Institute for Laboratory Animal Science and Central Animal Facility, Hannover Medical School, Hannover, Lower-Saxony, Germany
| | - Matthias Steglich
- Research Core Unit Genomics, Hannover Medical School, Hannover, Lower-Saxony, Germany
| | - Salvatore Oliviero
- Department of Life Sciences and Systems Biology, University of Torino, Torino, Italy
| | - Stefania Raimondo
- Department of Clinical and Biological Sciences & Neuroscience Institute Cavalieri Ottolenghi (NICO), University of Torino, Orbassano, Italy
| | - Dario Bizzotto
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Kirsten Haastert-Talini
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, Hannover, Lower-Saxony, Germany
- Centre for Systems Neuroscience (ZSN), Hannover Medical School, Hannover, Lower-Saxony, Germany
| | - Giulia Ronchi
- Department of Clinical and Biological Sciences & Neuroscience Institute Cavalieri Ottolenghi (NICO), University of Torino, Orbassano, Italy
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7
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Wang Y, Zhang Y, Wang Y, Chen H, Pan L, Liao X, Wang S. A Novel Form of Neuregulin 1 Type III Caused by N-Terminal Processing. Biomolecules 2023; 13:1756. [PMID: 38136627 PMCID: PMC10741733 DOI: 10.3390/biom13121756] [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: 11/22/2023] [Accepted: 12/04/2023] [Indexed: 12/24/2023] Open
Abstract
Nrg1 (Neuregulin 1) type III, a susceptible gene of schizophrenia, exhibits a critical role in the central nervous system and is essential at each stage of Schwann's cell development. Nrg1 type III comprises double-pass transmembrane domains, with the N-terminal and C-terminal localizing inside the cells. The N-terminal transmembrane helix partially overlaps with the cysteine-rich domain (CRD). In this study, Nrg1 type III constructs with different tags were transformed into cultured cells to verify whether CRD destroyed the transmembrane helix formation. We took advantage of immunofluorescent and immunoprecipitation assays on whole cells and analyzed the N-terminal distribution. Astonishingly, we found that a novel form of Nrg1 type III, about 10% of Nrg1 type III, omitted the N-terminal transmembrane helix, with the N-terminal positioning outside the membrane. The results indicated that the novel single-pass transmembrane status was a minor form of Nrg1 type III caused by N-terminal processing, while the major form was a double-pass transmembrane status.
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Affiliation(s)
- Yukai Wang
- School of Life Sciences, Nanchang University, Nanchang 330031, China
- Institute of Biomedical Innovation, Jiangxi Medical College, Nanchang University, Nanchang 330031, China
| | - Yu Zhang
- School of Life Sciences, Nanchang University, Nanchang 330031, China
- Institute of Biomedical Innovation, Jiangxi Medical College, Nanchang University, Nanchang 330031, China
- School of Basic Medical Sciences, Jiangxi Medical College, Nanchang University, Nanchang 330031, China
| | - Yingxing Wang
- School of Life Sciences, Nanchang University, Nanchang 330031, China
- Institute of Biomedical Innovation, Jiangxi Medical College, Nanchang University, Nanchang 330031, China
| | - Hong Chen
- School of Life Sciences, Nanchang University, Nanchang 330031, China
- Institute of Biomedical Innovation, Jiangxi Medical College, Nanchang University, Nanchang 330031, China
| | - Liangjing Pan
- Institute of Biomedical Innovation, Jiangxi Medical College, Nanchang University, Nanchang 330031, China
- School of Basic Medical Sciences, Jiangxi Medical College, Nanchang University, Nanchang 330031, China
| | - Xufeng Liao
- School of Life Sciences, Nanchang University, Nanchang 330031, China
- Institute of Biomedical Innovation, Jiangxi Medical College, Nanchang University, Nanchang 330031, China
| | - Shunqi Wang
- School of Life Sciences, Nanchang University, Nanchang 330031, China
- Institute of Biomedical Innovation, Jiangxi Medical College, Nanchang University, Nanchang 330031, China
- School of Basic Medical Sciences, Jiangxi Medical College, Nanchang University, Nanchang 330031, China
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8
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Gupta DP, Bhusal A, Rahman MH, Kim JH, Choe Y, Jang J, Jung HJ, Kim UK, Park JS, Maeng LS, Suk K, Song GJ. EBP50 is a key molecule for the Schwann cell-axon interaction in peripheral nerves. Prog Neurobiol 2023; 231:102544. [PMID: 37940033 DOI: 10.1016/j.pneurobio.2023.102544] [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: 04/11/2023] [Revised: 10/25/2023] [Accepted: 11/02/2023] [Indexed: 11/10/2023]
Abstract
Peripheral nerve injury disrupts the Schwann cell-axon interaction and the cellular communication between them. The peripheral nervous system has immense potential for regeneration extensively due to the innate plastic potential of Schwann cells (SCs) that allows SCs to interact with the injured axons and exert specific repair functions essential for peripheral nerve regeneration. In this study, we show that EBP50 is essential for the repair function of SCs and regeneration following nerve injury. The increased expression of EBP50 in the injured sciatic nerve of control mice suggested a significant role in regeneration. The ablation of EBP50 in mice resulted in delayed nerve repair, recovery of behavioral function, and remyelination following nerve injury. EBP50 deficiency led to deficits in SC functions, including proliferation, migration, cytoskeleton dynamics, and axon interactions. The adeno-associated virus (AAV)-mediated local expression of EBP50 improved SCs migration, functional recovery, and remyelination. ErbB2-related proteins were not differentially expressed in EBP50-deficient sciatic nerves following injury. EBP50 binds and stabilizes ErbB2 and activates the repair functions to promote regeneration. Thus, we identified EBP50 as a potent SC protein that can enhance the regeneration and functional recovery driven by NRG1-ErbB2 signaling, as well as a novel regeneration modulator capable of potential therapeutic effects.
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Affiliation(s)
- Deepak Prasad Gupta
- Translational Brain Research Center, International St. Mary's Hospital, Catholic Kwandong University, Incheon, Republic of Korea; Department of Pharmacology, Brain Science and Engineering Institute, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Anup Bhusal
- Department of Pharmacology, Brain Science and Engineering Institute, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Md Habibur Rahman
- Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Jae-Hong Kim
- Department of Pharmacology, Brain Science and Engineering Institute, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Youngshik Choe
- Korea Brain Research Institute, Daegu, Republic of Korea
| | - Jaemyung Jang
- Korea Brain Research Institute, Daegu, Republic of Korea
| | - Hyun Jin Jung
- Korea Brain Research Institute, Daegu, Republic of Korea
| | - Un-Kyung Kim
- Department of Biology, College of Natural Sciences, Kyungpook National University, Daegu, Republic of Korea
| | - Jin-Sung Park
- Department of Neurology, School of Medicine, Kyungpook National University, Kyungpook National University Chilgok Hospital, Daegu, Republic of Korea
| | - Lee-So Maeng
- Department of Hospital Pathology, Incheon St. Mary's Hospital College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Kyoungho Suk
- Department of Pharmacology, Brain Science and Engineering Institute, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Gyun Jee Song
- Translational Brain Research Center, International St. Mary's Hospital, Catholic Kwandong University, Incheon, Republic of Korea; Department of Medicine, College of Medicine, Catholic Kwandong University, Gangneung, Gangwon-do, Republic of Korea.
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9
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Daboussi L, Costaguta G, Gullo M, Jasinski N, Pessino V, O'Leary B, Lettieri K, Driscoll S, Pfaff SL. Mitf is a Schwann cell sensor of axonal integrity that drives nerve repair. Cell Rep 2023; 42:113282. [PMID: 38007688 PMCID: PMC11034927 DOI: 10.1016/j.celrep.2023.113282] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 08/04/2023] [Accepted: 09/28/2023] [Indexed: 11/27/2023] Open
Abstract
Schwann cells respond to acute axon damage by transiently transdifferentiating into specialized repair cells that restore sensorimotor function. However, the molecular systems controlling repair cell formation and function are not well defined, and consequently, it is unclear whether this form of cellular plasticity has a role in peripheral neuropathies. Here, we identify Mitf as a transcriptional sensor of axon damage under the control of Nrg-ErbB-PI3K-PI5K-mTorc2 signaling. Mitf regulates a core transcriptional program for generating functional repair Schwann cells following injury and during peripheral neuropathies caused by CMT4J and CMT4D. In the absence of Mitf, core genes for epithelial-to-mesenchymal transition, metabolism, and dedifferentiation are misexpressed, and nerve repair is disrupted. Our findings demonstrate that Schwann cells monitor axonal health using a phosphoinositide signaling system that controls Mitf nuclear localization, which is critical for activating cellular plasticity and counteracting neural disease.
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Affiliation(s)
- Lydia Daboussi
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines, La Jolla, CA 92037, USA; Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Giancarlo Costaguta
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines, La Jolla, CA 92037, USA; Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Miriam Gullo
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines, La Jolla, CA 92037, USA
| | - Nicole Jasinski
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines, La Jolla, CA 92037, USA
| | - Veronica Pessino
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines, La Jolla, CA 92037, USA
| | - Brendan O'Leary
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines, La Jolla, CA 92037, USA
| | - Karen Lettieri
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines, La Jolla, CA 92037, USA
| | - Shawn Driscoll
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines, La Jolla, CA 92037, USA
| | - Samuel L Pfaff
- Gene Expression Laboratory, Salk Institute for Biological Studies, 10010 North Torrey Pines, La Jolla, CA 92037, USA.
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10
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Gu X, Rahman FS, Bendale G, Tran B, Miyata JF, Hernandez A, Anand S, Romero-Ortega MI. Pleiotrophin-Neuregulin1 promote axon regeneration and sorting in conduit repair of critical nerve gap injuries. RESEARCH SQUARE 2023:rs.3.rs-3429258. [PMID: 37986821 PMCID: PMC10659554 DOI: 10.21203/rs.3.rs-3429258/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Significant challenges remain in the treatment of critical nerve gap injuries using artificial nerve conduits. We previously reported successful axon regeneration across a 40 mm nerve gap using a biosynthetic nerve implant (BNI) with multi-luminal synergistic growth factor release. However, axon sorting, remyelination, and functional recovery were limited. Neuregulin1 (NRG1) plays a significant role in regulating the proliferation and differentiation of Schwann cells (SCs) during development and after injury. We hypothesize that the release of NRG1 type III combined with pleiotrophin (PTN) in the BNI will enhance axon growth, remyelination, and function of regenerated nerves across a critical gap. A rabbit 40 mm peroneal gap injury model was used to investigate the therapeutic efficacy of BNIs containing either NRG1, PTN, or PTN+NRG1 growth factor release. We found that NRG1 treatment doubled the number of regenerated axons (1276±895) compared to empty controls (633±666) and PTN tripled this number (2270±989). NRG1 also significantly increased the number of SOX10+ Schwann cells in mid-conduit (20.42%±11.78%) and reduced the number of abnormal Remak axon bundles. The combination of PTN+NRG1 increased axon diameter (1.70±1.06) vs control (1.21±0.77) (p<0.01), with 15.35% of axons above 3 μm, comparable to autograft. However, the total number of remyelinated axons was not increased by the added NRG1 release, which correlated with absence of axonal NRG1 type III expression in the regenerated axons. Electrophysiological evaluation showed higher muscle force recruitment (23.8±16.0 mN vs 17.4±1.4 mN) and maximum evoked compound motor action potential (353 μV vs 37 μV) in PTN-NRG1 group versus control, which correlated with the improvement in the toe spread recovery observed in PTN-NRG1 treated animals (0.64±0.02) vs control (0.50±0.01). These results revealed the need of a combination of pro-regenerative and remyelinating growth factor combination therapy for the repair of critical nerve gaps.
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Affiliation(s)
- Xingjian Gu
- Department of Biomedical Engineering, University of Houston, Houston TX 77204
| | - Farial S. Rahman
- Department of Biomedical Engineering, University of Houston, Houston TX 77204
| | - G Bendale
- Department of Biomedical Engineering, University of Houston, Houston TX 77204
| | - B Tran
- Department of Biomedical Engineering, University of Houston, Houston TX 77204
| | - JF Miyata
- Department of Biomedical Engineering, University of Houston, Houston TX 77204
| | - A Hernandez
- Department of Biomedical Engineering, University of Houston, Houston TX 77204
| | - S Anand
- Department of Biomedical Engineering, University of Houston, Houston TX 77204
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11
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Xiao J. Thirty years of BDNF study in central myelination: From biology to therapy. J Neurochem 2023; 167:321-336. [PMID: 37747083 DOI: 10.1111/jnc.15968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 09/05/2023] [Accepted: 09/07/2023] [Indexed: 09/26/2023]
Abstract
Being the highest expressed neurotrophin in the mammalian brain, the brain-derived neurotrophic factor (BDNF) is essential to neural development and plasticity in both health and diseases. Following the discovery of BDNF by Yves-Alain Barde in 1982, the main feature of BDNF's activity in myelination was first described by Cellerino et al. in 1997. Since then, genetic manipulation of the BDNF-encoding gene and its receptors in murine models has revealed the contribution of BDNF to the myelinating process in the central nervous system (CNS). The series of BDNF or receptor mouse mutants as well as the BDNF polymorphism in humans have provided new insights into the roles that BDNF signaling plays in myelination in a complex manner. 2024 marks the 30th year of BDNF's research in myelination. Here, we share our perspective on the 30-year history of BDNF in the field of CNS myelination from phenotyping to therapeutic development, focusing on genetic evidence regarding the mechanism by which BDNF regulates myelin formation and repair in the CNS. This review also discusses the current hypotheses of BDNF's action on CNS myelination: axonal- and oligodendroglial-driven mechanisms, which may be ultimately activity-dependent. Last, this review raises the challenges and opportunities of developing BDNF-based therapies for neurodegenerative diseases, opening unanswered questions for future investigation.
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Affiliation(s)
- Junhua Xiao
- School of Health Sciences, Swinburne University of Technology, Hawthorn, Victoria, Australia
- School of Allied Health, La Trobe University, Bundoora, Victoria, Australia
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12
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Mutschler C, Fazal SV, Schumacher N, Loreto A, Coleman MP, Arthur-Farraj P. Schwann cells are axo-protective after injury irrespective of myelination status in mouse Schwann cell-neuron cocultures. J Cell Sci 2023; 136:jcs261557. [PMID: 37642648 PMCID: PMC10546878 DOI: 10.1242/jcs.261557] [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: 08/14/2023] [Accepted: 08/18/2023] [Indexed: 08/31/2023] Open
Abstract
Myelinating Schwann cell (SC)-dorsal root ganglion (DRG) neuron cocultures are an important technique for understanding cell-cell signalling and interactions during peripheral nervous system (PNS) myelination, injury, and regeneration. Although methods using rat SCs and neurons or mouse DRG explants are commonplace, there are no established protocols for compartmentalised myelinating cocultures with dissociated mouse cells. There consequently is a need for a coculture protocol that allows separate genetic manipulation of mouse SCs or neurons, or use of cells from different transgenic animals to complement in vivo mouse experiments. However, inducing myelination of dissociated mouse SCs in culture is challenging. Here, we describe a new method to coculture dissociated mouse SCs and DRG neurons in microfluidic chambers and induce robust myelination. Cocultures can be axotomised to study injury and used for drug treatments, and cells can be lentivirally transduced for live imaging. We used this model to investigate axon degeneration after traumatic axotomy and find that SCs, irrespective of myelination status, are axo-protective. At later timepoints after injury, live imaging of cocultures shows that SCs break up, ingest and clear axonal debris.
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Affiliation(s)
- Clara Mutschler
- John Van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0PY, UK
| | - Shaline V. Fazal
- John Van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0PY, UK
- Wellcome-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge CB2 0AW, UK
| | - Nathalie Schumacher
- Laboratory of Nervous System Disorders and Therapies, GIGA Neurosciences, University of Liège, 4000 Liège, Belgium
| | - Andrea Loreto
- John Van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0PY, UK
| | - Michael P. Coleman
- John Van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0PY, UK
| | - Peter Arthur-Farraj
- John Van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0PY, UK
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13
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El-Bazzal L, Ghata A, Estève C, Gadacha J, Quintana P, Castro C, Roeckel-Trévisiol N, Lembo F, Lenfant N, Mégarbané A, Borg JP, Lévy N, Bartoli M, Poitelon Y, Roubertoux PL, Delague V, Bernard-Marissal N. Imbalance of NRG1-ERBB2/3 signalling underlies altered myelination in Charcot-Marie-Tooth disease 4H. Brain 2023; 146:1844-1858. [PMID: 36314052 PMCID: PMC10151191 DOI: 10.1093/brain/awac402] [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: 03/25/2022] [Revised: 08/30/2022] [Accepted: 10/02/2022] [Indexed: 11/12/2022] Open
Abstract
Charcot-Marie-Tooth (CMT) disease is one of the most common inherited neurological disorders, affecting either axons from the motor and/or sensory neurons or Schwann cells of the peripheral nervous system (PNS) and caused by more than 100 genes. We previously identified mutations in FGD4 as responsible for CMT4H, an autosomal recessive demyelinating form of CMT disease. FGD4 encodes FRABIN, a GDP/GTP nucleotide exchange factor, particularly for the small GTPase Cdc42. Remarkably, nerves from patients with CMT4H display excessive redundant myelin figures called outfoldings that arise from focal hypermyelination, suggesting that FRABIN could play a role in the control of PNS myelination. To gain insights into the role of FGD4/FRABIN in Schwann cell myelination, we generated a knockout mouse model (Fgd4SC-/-), with conditional ablation of Fgd4 in Schwann cells. We show that the specific deletion of FRABIN in Schwann cells leads to aberrant myelination in vitro, in dorsal root ganglia neuron/Schwann cell co-cultures, as well as in vivo, in distal sciatic nerves from Fgd4SC-/- mice. We observed that those myelination defects are related to an upregulation of some interactors of the NRG1 type III/ERBB2/3 signalling pathway, which is known to ensure a proper level of myelination in the PNS. Based on a yeast two-hybrid screen, we identified SNX3 as a new partner of FRABIN, which is involved in the regulation of endocytic trafficking. Interestingly, we showed that the loss of FRABIN impairs endocytic trafficking, which may contribute to the defective NRG1 type III/ERBB2/3 signalling and myelination. Using RNA-Seq, in vitro, we identified new potential effectors of the deregulated pathways, such as ERBIN, RAB11FIP2 and MAF, thereby providing cues to understand how FRABIN contributes to proper ERBB2 trafficking or even myelin membrane addition through cholesterol synthesis. Finally, we showed that the re-establishment of proper levels of the NRG1 type III/ERBB2/3 pathway using niacin treatment reduces myelin outfoldings in nerves of CMT4H mice. Overall, our work reveals a new role of FRABIN in the regulation of NRG1 type III/ERBB2/3 NRG1signalling and myelination and opens future therapeutic strategies based on the modulation of the NRG1 type III/ERBB2/3 pathway to reduce CMT4H pathology and more generally other demyelinating types of CMT disease.
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Affiliation(s)
- Lara El-Bazzal
- Aix Marseille Univ, INSERM, MMG, U 1251, Marseille, France
| | - Adeline Ghata
- Aix Marseille Univ, INSERM, MMG, U 1251, Marseille, France
| | | | - Jihane Gadacha
- Aix Marseille Univ, INSERM, MMG, U 1251, Marseille, France
| | | | | | | | - Frédérique Lembo
- Aix Marseille Univ, INSERM, CNRS, CRCM, Institut Paoli-Calmettes, Marseille, France
| | | | - André Mégarbané
- Department of Human Genetics, Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Beirut, Lebanon
| | - Jean-Paul Borg
- Aix Marseille Univ, INSERM, CNRS, CRCM, Institut Paoli-Calmettes, Marseille, France
| | - Nicolas Lévy
- Aix Marseille Univ, INSERM, MMG, U 1251, Marseille, France
| | - Marc Bartoli
- Aix Marseille Univ, INSERM, MMG, U 1251, Marseille, France
| | - Yannick Poitelon
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, NY, USA
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14
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Kong L, Hassinan CW, Gerstner F, Buettner JM, Petigrow JB, Valdivia DO, Chan-Cortés MH, Mistri A, Cao A, McGaugh SA, Denton M, Brown S, Ross J, Schwab MH, Simon CM, Sumner CJ. Boosting neuregulin 1 type-III expression hastens SMA motor axon maturation. Acta Neuropathol Commun 2023; 11:53. [PMID: 36997967 PMCID: PMC10061791 DOI: 10.1186/s40478-023-01551-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 03/12/2023] [Indexed: 04/01/2023] Open
Abstract
Intercellular communication between axons and Schwann cells is critical for attaining the complex morphological steps necessary for axon maturation. In the early onset motor neuron disease spinal muscular atrophy (SMA), many motor axons are not ensheathed by Schwann cells nor grow sufficiently in radial diameter to become myelinated. These developmentally arrested motor axons are dysfunctional and vulnerable to rapid degeneration, limiting efficacy of current SMA therapeutics. We hypothesized that accelerating SMA motor axon maturation would improve their function and reduce disease features. A principle regulator of peripheral axon development is neuregulin 1 type III (NRG1-III). Expressed on axon surfaces, it interacts with Schwann cell receptors to mediate axon ensheathment and myelination. We examined NRG1 mRNA and protein expression levels in human and mouse SMA tissues and observed reduced expression in SMA spinal cord and in ventral, but not dorsal root axons. To determine the impact of neuronal NRG1-III overexpression on SMA motor axon development, we bred NRG1-III overexpressing mice to SMA∆7 mice. Neonatally, elevated NRG1-III expression increased SMA ventral root size as well as axon segregation, diameter, and myelination resulting in improved motor axon conduction velocities. NRG1-III was not able to prevent distal axonal degeneration nor improve axon electrophysiology, motor behavior, or survival of older mice. Together these findings demonstrate that early SMA motor axon developmental impairments can be ameliorated by a molecular strategy independent of SMN replacement providing hope for future SMA combinatorial therapeutic approaches.
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Affiliation(s)
- Lingling Kong
- Departments of Neurology, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Rangos Building Room 234, Baltimore, MD, 21205, USA
| | - Cera W Hassinan
- Departments of Neurology, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Rangos Building Room 234, Baltimore, MD, 21205, USA
| | - Florian Gerstner
- Carl-Ludwig-Institute for Physiology, Leipzig University, Leipzig, Germany
| | - Jannik M Buettner
- Carl-Ludwig-Institute for Physiology, Leipzig University, Leipzig, Germany
| | - Jeffrey B Petigrow
- Departments of Neurology, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Rangos Building Room 234, Baltimore, MD, 21205, USA
| | - David O Valdivia
- Departments of Neurology, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Rangos Building Room 234, Baltimore, MD, 21205, USA
| | - Michelle H Chan-Cortés
- Departments of Neurology, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Rangos Building Room 234, Baltimore, MD, 21205, USA
| | - Amy Mistri
- Departments of Neurology, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Rangos Building Room 234, Baltimore, MD, 21205, USA
| | - Annie Cao
- Departments of Neurology, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Rangos Building Room 234, Baltimore, MD, 21205, USA
| | - Scott Alan McGaugh
- Departments of Neurology, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Rangos Building Room 234, Baltimore, MD, 21205, USA
| | - Madeline Denton
- Departments of Neurology, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Rangos Building Room 234, Baltimore, MD, 21205, USA
| | - Stephen Brown
- Departments of Neurology, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Rangos Building Room 234, Baltimore, MD, 21205, USA
| | - Joshua Ross
- Departments of Neurology, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Rangos Building Room 234, Baltimore, MD, 21205, USA
| | - Markus H Schwab
- Department of Neuropathology, University Hospital Leipzig, Leipzig, Germany
| | - Christian M Simon
- Carl-Ludwig-Institute for Physiology, Leipzig University, Leipzig, Germany
| | - Charlotte J Sumner
- Departments of Neurology, Johns Hopkins University School of Medicine, 855 North Wolfe Street, Rangos Building Room 234, Baltimore, MD, 21205, USA.
- Departments of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
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15
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Schwann cell functions in peripheral nerve development and repair. Neurobiol Dis 2023; 176:105952. [PMID: 36493976 DOI: 10.1016/j.nbd.2022.105952] [Citation(s) in RCA: 32] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 11/23/2022] [Accepted: 12/05/2022] [Indexed: 12/12/2022] Open
Abstract
The glial cell of the peripheral nervous system (PNS), the Schwann cell (SC), counts among the most multifaceted cells of the body. During development, SCs secure neuronal survival and participate in axonal path finding. Simultaneously, they orchestrate the architectural set up of the developing nerves, including the blood vessels and the endo-, peri- and epineurial layers. Perinatally, in rodents, SCs radially sort and subsequently myelinate individual axons larger than 1 μm in diameter, while small calibre axons become organised in non-myelinating Remak bundles. SCs have a vital role in maintaining axonal health throughout life and several specialized SC types perform essential functions at specific locations, such as terminal SC at the neuromuscular junction (NMJ) or SC within cutaneous sensory end organs. In addition, neural crest derived satellite glia maintain a tight communication with the soma of sensory, sympathetic, and parasympathetic neurons and neural crest derivatives are furthermore an indispensable part of the enteric nervous system. The remarkable plasticity of SCs becomes evident in the context of a nerve injury, where SC transdifferentiate into intriguing repair cells, which orchestrate a regenerative response that promotes nerve repair. Indeed, the multiple adaptations of SCs are captivating, but remain often ill-resolved on the molecular level. Here, we summarize and discuss the knowns and unknowns of the vast array of functions that this single cell type can cover in peripheral nervous system development, maintenance, and repair.
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16
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Yuan Y, Wang Y, Wu S, Zhao MY. Review: Myelin clearance is critical for regeneration after peripheral nerve injury. Front Neurol 2022; 13:908148. [PMID: 36588879 PMCID: PMC9801717 DOI: 10.3389/fneur.2022.908148] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 11/17/2022] [Indexed: 12/23/2022] Open
Abstract
Traumatic peripheral nerve injury occurs frequently and is a major clinical and public health problem that can lead to functional impairment and permanent disability. Despite the availability of modern diagnostic procedures and advanced microsurgical techniques, active recovery after peripheral nerve repair is often unsatisfactory. Peripheral nerve regeneration involves several critical events, including the recreation of the microenvironment and remyelination. Results from previous studies suggest that the peripheral nervous system (PNS) has a greater capacity for repair than the central nervous system. Thus, it will be important to understand myelin and myelination specifically in the PNS. This review provides an update on myelin biology and myelination in the PNS and discusses the mechanisms that promote myelin clearance after injury. The roles of Schwann cells and macrophages are considered at length, together with the possibility of exogenous intervention.
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Affiliation(s)
- YiMing Yuan
- Laboratory of Brain Function and Neurorehabilitation, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Yan Wang
- Laboratory of Brain Function and Neurorehabilitation, Heilongjiang University of Chinese Medicine, Harbin, China,Department of Rehabilitation, The Second Affiliated Hospital of Heilongjiang University of Chinese Medicine, Harbin, China,*Correspondence: Yan Wang
| | - ShanHong Wu
- Laboratory of Brain Function and Neurorehabilitation, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Ming Yue Zhao
- Laboratory of Brain Function and Neurorehabilitation, Heilongjiang University of Chinese Medicine, Harbin, China,Department of Rehabilitation, The Second Affiliated Hospital of Heilongjiang University of Chinese Medicine, Harbin, China
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17
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Corty MM, Hulegaard AL, Hill JQ, Sheehan AE, Aicher SA, Freeman MR. Discoidin domain receptor regulates ensheathment, survival and caliber of peripheral axons. Development 2022; 149:281293. [PMID: 36355066 PMCID: PMC10112903 DOI: 10.1242/dev.200636] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 10/27/2022] [Indexed: 11/12/2022]
Abstract
Most invertebrate axons and small-caliber axons in mammalian peripheral nerves are unmyelinated but still ensheathed by glia. Here, we use Drosophila wrapping glia to study the development and function of non-myelinating axon ensheathment, which is poorly understood. Selective ablation of these glia from peripheral nerves severely impaired larval locomotor behavior. In an in vivo RNA interference screen to identify glial genes required for axon ensheathment, we identified the conserved receptor tyrosine kinase Discoidin domain receptor (Ddr). In larval peripheral nerves, loss of Ddr resulted in severely reduced ensheathment of axons and reduced axon caliber, and we found a strong dominant genetic interaction between Ddr and the type XV/XVIII collagen Multiplexin (Mp), suggesting that Ddr functions as a collagen receptor to drive axon wrapping. In adult nerves, loss of Ddr decreased long-term survival of sensory neurons and significantly reduced axon caliber without overtly affecting ensheathment. Our data establish essential roles for non-myelinating glia in nerve development, maintenance and function, and identify Ddr as a key regulator of axon-glia interactions during ensheathment and establishment of axon caliber.
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Affiliation(s)
- Megan M Corty
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | | | - Jo Q Hill
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA
| | - Amy E Sheehan
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Sue A Aicher
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA
| | - Marc R Freeman
- Vollum Institute, Oregon Health & Science University, Portland, OR 97239, USA
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18
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Development and In Vitro Differentiation of Schwann Cells. Cells 2022; 11:cells11233753. [PMID: 36497014 PMCID: PMC9739763 DOI: 10.3390/cells11233753] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 11/16/2022] [Accepted: 11/22/2022] [Indexed: 11/25/2022] Open
Abstract
Schwann cells are glial cells of the peripheral nervous system. They exist in several subtypes and perform a variety of functions in nerves. Their derivation and culture in vitro are interesting for applications ranging from disease modeling to tissue engineering. Since primary human Schwann cells are challenging to obtain in large quantities, in vitro differentiation from other cell types presents an alternative. Here, we first review the current knowledge on the developmental signaling mechanisms that determine neural crest and Schwann cell differentiation in vivo. Next, an overview of studies on the in vitro differentiation of Schwann cells from multipotent stem cell sources is provided. The molecules frequently used in those protocols and their involvement in the relevant signaling pathways are put into context and discussed. Focusing on hiPSC- and hESC-based studies, different protocols are described and compared, regarding cell sources, differentiation methods, characterization of cells, and protocol efficiency. A brief insight into developments regarding the culture and differentiation of Schwann cells in 3D is given. In summary, this contribution provides an overview of the current resources and methods for the differentiation of Schwann cells, it supports the comparison and refinement of protocols and aids the choice of suitable methods for specific applications.
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19
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Lysko DE, Talbot WS. Unmyelinated sensory neurons use Neuregulin signals to promote myelination of interneurons in the CNS. Cell Rep 2022; 41:111669. [PMID: 36384112 PMCID: PMC9719401 DOI: 10.1016/j.celrep.2022.111669] [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: 04/01/2022] [Revised: 09/06/2022] [Accepted: 10/25/2022] [Indexed: 11/17/2022] Open
Abstract
The signaling mechanisms neurons use to modulate myelination of circuits in the central nervous system (CNS) are only partly understood. Through analysis of isoform-specific neuregulin1 (nrg1) mutants in zebrafish, we demonstrate that nrg1 type II is an important regulator of myelination of two classes of spinal cord interneurons. Surprisingly, nrg1 type II expression is prominent in unmyelinated Rohon-Beard sensory neurons, whereas myelination of neighboring interneurons is reduced in nrg1 type II mutants. Cell-type-specific loss-of-function studies indicate that nrg1 type II is required in Rohon-Beard neurons to signal to other neurons, not oligodendrocytes, to modulate spinal cord myelination. Together, our data support a model in which unmyelinated neurons express Nrg1 type II proteins to regulate myelination of neighboring neurons, a mode of action that may coordinate the functions of unmyelinated and myelinated neurons in the CNS.
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Affiliation(s)
- Daniel E Lysko
- Department of Developmental Biology, Stanford University, Stanford, CA 94305, USA
| | - William S Talbot
- Department of Developmental Biology, Stanford University, Stanford, CA 94305, USA.
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20
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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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21
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Liu Y, Yue W, Yu S, Zhou T, Zhang Y, Zhu R, Song B, Guo T, Liu F, Huang Y, Wu T, Wang H. A physical perspective to understand myelin II: The physical origin of myelin development. Front Neurosci 2022; 16:951998. [PMID: 36263368 PMCID: PMC9574017 DOI: 10.3389/fnins.2022.951998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 09/05/2022] [Indexed: 11/13/2022] Open
Abstract
The physical principle of myelin development is obtained from our previous study by explaining Peter’s quadrant mystery: an externally applied negative and positive E-field can promote and inhibit the growth of the inner tongue of the myelin sheath, respectively. In this study, this principle is considered as a fundamental hypothesis, named Hypothesis-E, to explain more phenomena about myelin development systematically. Specifically, the g-ratio and the fate of the Schwann cell’s differentiation are explained in terms of the E-field. Moreover, an experiment is proposed to validate this theory.
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Affiliation(s)
- Yonghong Liu
- Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen, China
| | - Wenji Yue
- Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen, China
| | - Shoujun Yu
- Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen, China
| | - Tian Zhou
- Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen, China
| | - Yapeng Zhang
- Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen, China
| | - Ran Zhu
- Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen, China
| | - Bing Song
- Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen, China
| | - Tianruo Guo
- Key Laboratory of Health Bioinformatics, Chinese Academy of Sciences, Shenzhen, China
| | - Fenglin Liu
- Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen, China
| | - Yubin Huang
- Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen, China
| | - Tianzhun Wu
- Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen, China
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW, Australia
- *Correspondence: Tianzhun Wu,
| | - Hao Wang
- Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen, China
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, NSW, Australia
- Hao Wang,
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22
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Akkuratova N, Faure L, Kameneva P, Kastriti ME, Adameyko I. Developmental heterogeneity of embryonic neuroendocrine chromaffin cells and their maturation dynamics. Front Endocrinol (Lausanne) 2022; 13:1020000. [PMID: 36237181 PMCID: PMC9553123 DOI: 10.3389/fendo.2022.1020000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 09/07/2022] [Indexed: 11/13/2022] Open
Abstract
During embryonic development, nerve-associated Schwann cell precursors (SCPs) give rise to chromaffin cells of the adrenal gland via the "bridge" transient stage, according to recent functional experiments and single cell data from humans and mice. However, currently existing data do not resolve the finest heterogeneity of developing chromaffin populations. Here we took advantage of deep SmartSeq2 transcriptomic sequencing to expand our collection of individual cells from the developing murine sympatho-adrenal anlage and uncover the microheterogeneity of embryonic chromaffin cells and their corresponding developmental paths. We discovered that SCPs on the splachnic nerve show a high degree of microheterogeneity corresponding to early biases towards either Schwann or chromaffin terminal fates. Furthermore, we found that a post-"bridge" population of developing chromaffin cells gives rise to persisting oxygen-sensing chromaffin cells and the two terminal populations (adrenergic and noradrenergic) via diverging differentiation paths. Taken together, we provide a thorough identification of novel markers of adrenergic and noradrenergic populations in developing adrenal glands and report novel differentiation paths leading to them.
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Affiliation(s)
- Natalia Akkuratova
- Department of Physiology and Pharmacology, Karolinska Institute, Solna, Sweden
| | - Louis Faure
- Department of Neuroimmunology, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Polina Kameneva
- Department of Physiology and Pharmacology, Karolinska Institute, Solna, Sweden
- Department of Neuroimmunology, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Maria Eleni Kastriti
- Department of Physiology and Pharmacology, Karolinska Institute, Solna, Sweden
- Department of Neuroimmunology, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Igor Adameyko
- Department of Physiology and Pharmacology, Karolinska Institute, Solna, Sweden
- Department of Neuroimmunology, Center for Brain Research, Medical University of Vienna, Vienna, Austria
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23
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Lysko DE, Meireles AM, Folland C, McNamara E, Laing NG, Lamont PJ, Ravenscroft G, Talbot WS. Partial loss-of-function variant in neuregulin 1 identified in family with heritable peripheral neuropathy. Hum Mutat 2022; 43:1216-1223. [PMID: 35485770 PMCID: PMC9357049 DOI: 10.1002/humu.24393] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 03/24/2022] [Accepted: 04/27/2022] [Indexed: 11/11/2022]
Abstract
Neuregulin 1 signals are essential for the development and function of Schwann cells, which form the myelin sheath on peripheral axons. Disruption of myelin in the peripheral nervous system can lead to peripheral neuropathy, which is characterized by reduced axonal conduction velocity and sensorimotor deficits. Charcot-Marie-Tooth disease is a group of heritable peripheral neuropathies that may be caused by variants in nearly 100 genes. Despite the evidence that Neuregulin 1 is essential for many aspects of Schwann cell development, previous studies have not reported variants in the neuregulin 1 gene (NRG1) in patients with peripheral neuropathy. We have identified a rare missense variant in NRG1 that is homozygous in a patient with sensory and motor deficits consistent with mixed axonal and de-myelinating peripheral neuropathy. Our in vivo functional studies in zebrafish indicate that the patient variant partially reduces NRG1 function. This study tentatively suggests that variants at the NRG1 locus may cause peripheral neuropathy and that NRG1 should be investigated in families with peripheral neuropathy of unknown cause.
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Affiliation(s)
- Daniel E Lysko
- Department of Developmental Biology, Stanford University, Stanford, CA 94305, USA
| | - Ana M Meireles
- Department of Developmental Biology, Stanford University, Stanford, CA 94305, USA
| | - Chiara Folland
- Harry Perkins Institute of Medical Research, Nedlands, WA, 6009, Australia
- Centre of Medical Research, University of Western Australia, Nedlands, WA, 6009, Australia
| | - Elyshia McNamara
- Harry Perkins Institute of Medical Research, Nedlands, WA, 6009, Australia
- Centre of Medical Research, University of Western Australia, Nedlands, WA, 6009, Australia
| | - Nigel G Laing
- Harry Perkins Institute of Medical Research, Nedlands, WA, 6009, Australia
- Centre of Medical Research, University of Western Australia, Nedlands, WA, 6009, Australia
| | | | - Gianina Ravenscroft
- Harry Perkins Institute of Medical Research, Nedlands, WA, 6009, Australia
- Centre of Medical Research, University of Western Australia, Nedlands, WA, 6009, Australia
- School of Biomedical Sciences, University of Western Australia, Nedlands, WA, 6009, Australia
| | - William S Talbot
- Department of Developmental Biology, Stanford University, Stanford, CA 94305, USA
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24
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Kastriti ME, Faure L, Von Ahsen D, Bouderlique TG, Boström J, Solovieva T, Jackson C, Bronner M, Meijer D, Hadjab S, Lallemend F, Erickson A, Kaucka M, Dyachuk V, Perlmann T, Lahti L, Krivanek J, Brunet J, Fried K, Adameyko I. Schwann cell precursors represent a neural crest-like state with biased multipotency. EMBO J 2022; 41:e108780. [PMID: 35815410 PMCID: PMC9434083 DOI: 10.15252/embj.2021108780] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 06/14/2022] [Accepted: 06/15/2022] [Indexed: 12/29/2022] Open
Abstract
Schwann cell precursors (SCPs) are nerve-associated progenitors that can generate myelinating and non-myelinating Schwann cells but also are multipotent like the neural crest cells from which they originate. SCPs are omnipresent along outgrowing peripheral nerves throughout the body of vertebrate embryos. By using single-cell transcriptomics to generate a gene expression atlas of the entire neural crest lineage, we show that early SCPs and late migratory crest cells have similar transcriptional profiles characterised by a multipotent "hub" state containing cells biased towards traditional neural crest fates. SCPs keep diverging from the neural crest after being primed towards terminal Schwann cells and other fates, with different subtypes residing in distinct anatomical locations. Functional experiments using CRISPR-Cas9 loss-of-function further show that knockout of the common "hub" gene Sox8 causes defects in neural crest-derived cells along peripheral nerves by facilitating differentiation of SCPs towards sympathoadrenal fates. Finally, specific tumour populations found in melanoma, neurofibroma and neuroblastoma map to different stages of SCP/Schwann cell development. Overall, SCPs resemble migrating neural crest cells that maintain multipotency and become transcriptionally primed towards distinct lineages.
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Affiliation(s)
- Maria Eleni Kastriti
- Department of Molecular Neuroscience, Center for Brain ResearchMedical University ViennaViennaAustria
- Department of Physiology and PharmacologyKarolinska InstitutetStockholmSweden
- Department of Neuroimmunology, Center for Brain ResearchMedical University ViennaViennaAustria
| | - Louis Faure
- Department of Neuroimmunology, Center for Brain ResearchMedical University ViennaViennaAustria
| | - Dorothea Von Ahsen
- Department of Neuroimmunology, Center for Brain ResearchMedical University ViennaViennaAustria
| | | | - Johan Boström
- Department of Neuroimmunology, Center for Brain ResearchMedical University ViennaViennaAustria
| | - Tatiana Solovieva
- Division of Biology and Biological EngineeringCalifornia Institute of TechnologyPasadenaCAUSA
| | - Cameron Jackson
- Division of Biology and Biological EngineeringCalifornia Institute of TechnologyPasadenaCAUSA
| | - Marianne Bronner
- Division of Biology and Biological EngineeringCalifornia Institute of TechnologyPasadenaCAUSA
| | - Dies Meijer
- Centre for Discovery Brain SciencesUniversity of EdinburghEdinburghUK
| | - Saida Hadjab
- Department of NeuroscienceKarolinska InstitutetStockholmSweden
| | | | - Alek Erickson
- Department of Physiology and PharmacologyKarolinska InstitutetStockholmSweden
| | - Marketa Kaucka
- Max Planck Institute for Evolutionary BiologyPlönGermany
| | | | - Thomas Perlmann
- Department of Cell and Molecular BiologyKarolinska InstitutetStockholmSweden
| | - Laura Lahti
- Department of Cell and Molecular BiologyKarolinska InstitutetStockholmSweden
| | - Jan Krivanek
- Department of Histology and Embryology, Faculty of MedicineMasaryk UniversityBrnoCzech Republic
| | - Jean‐Francois Brunet
- Institut de Biologie de l'ENS (IBENS), INSERM, CNRS, École Normale SupérieurePSL Research UniversityParisFrance
| | - Kaj Fried
- Department of NeuroscienceKarolinska InstitutetStockholmSweden
| | - Igor Adameyko
- Department of Physiology and PharmacologyKarolinska InstitutetStockholmSweden
- Department of Neuroimmunology, Center for Brain ResearchMedical University ViennaViennaAustria
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25
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McMorrow LA, Kosalko A, Robinson D, Saiani A, Reid AJ. Advancing Our Understanding of the Chronically Denervated Schwann Cell: A Potential Therapeutic Target? Biomolecules 2022; 12:1128. [PMID: 36009023 PMCID: PMC9406133 DOI: 10.3390/biom12081128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 08/04/2022] [Accepted: 08/11/2022] [Indexed: 11/25/2022] Open
Abstract
Outcomes for patients following major peripheral nerve injury are extremely poor. Despite advanced microsurgical techniques, the recovery of function is limited by an inherently slow rate of axonal regeneration. In particular, a time-dependent deterioration in the ability of the distal stump to support axonal growth is a major determinant to the failure of reinnervation. Schwann cells (SC) are crucial in the orchestration of nerve regeneration; their plasticity permits the adoption of a repair phenotype following nerve injury. The repair SC modulates the initial immune response, directs myelin clearance, provides neurotrophic support and remodels the distal nerve. These functions are critical for regeneration; yet the repair phenotype is unstable in the setting of chronic denervation. This phenotypic instability accounts for the deteriorating regenerative support offered by the distal nerve stump. Over the past 10 years, our understanding of the cellular machinery behind this repair phenotype, in particular the role of c-Jun, has increased exponentially, creating opportunities for therapeutic intervention. This review will cover the activation of the repair phenotype in SC, the effects of chronic denervation on SC and current strategies to 'hack' these cellular pathways toward supporting more prolonged periods of neural regeneration.
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Affiliation(s)
- Liam A. McMorrow
- Blond McIndoe Laboratories, Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9PL, UK
- Department of Plastic Surgery & Burns, Wythenshawe Hospital, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester M23 9LT, UK
| | - Adrian Kosalko
- Blond McIndoe Laboratories, Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9PL, UK
| | - Daniel Robinson
- Blond McIndoe Laboratories, Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9PL, UK
| | - Alberto Saiani
- School of Materials & Manchester Institute of Biotechnology, Faculty of Science and Engineering, University of Manchester, Manchester M13 9PL, UK
| | - Adam J. Reid
- Blond McIndoe Laboratories, Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9PL, UK
- Department of Plastic Surgery & Burns, Wythenshawe Hospital, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester M23 9LT, UK
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26
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Veneri FA, Prada V, Mastrangelo R, Ferri C, Nobbio L, Passalacqua M, Milanesi M, Bianchi F, Del Carro U, Vallat JM, Duong P, Svaren J, Schenone A, Grandis M, D’Antonio M. A novel mouse model of CMT1B identifies hyperglycosylation as a new pathogenetic mechanism. Hum Mol Genet 2022; 31:4255-4274. [PMID: 35908287 PMCID: PMC9759335 DOI: 10.1093/hmg/ddac170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 07/19/2022] [Accepted: 07/20/2022] [Indexed: 01/21/2023] Open
Abstract
Mutations in the Myelin Protein Zero gene (MPZ), encoding P0, the major structural glycoprotein of peripheral nerve myelin, are the cause of Charcot-Marie-Tooth (CMT) type 1B neuropathy, and most P0 mutations appear to act through gain-of-function mechanisms. Here, we investigated how misglycosylation, a pathomechanism encompassing several genetic disorders, may affect P0 function. Using in vitro assays, we showed that gain of glycosylation is more damaging for P0 trafficking and functionality as compared with a loss of glycosylation. Hence, we generated, via CRISPR/Cas9, a mouse model carrying the MPZD61N mutation, predicted to generate a new N-glycosylation site in P0. In humans, MPZD61N causes a severe early-onset form of CMT1B, suggesting that hyperglycosylation may interfere with myelin formation, leading to pathology. We show here that MPZD61N/+ mice develop a tremor as early as P15 which worsens with age and correlates with a significant motor impairment, reduced muscular strength and substantial alterations in neurophysiology. The pathological analysis confirmed a dysmyelinating phenotype characterized by diffuse hypomyelination and focal hypermyelination. We find that the mutant P0D61N does not cause significant endoplasmic reticulum stress, a common pathomechanism in CMT1B, but is properly trafficked to myelin where it causes myelin uncompaction. Finally, we show that myelinating dorsal root ganglia cultures from MPZD61N mice replicate some of the abnormalities seen in vivo, suggesting that they may represent a valuable tool to investigate therapeutic approaches. Collectively, our data indicate that the MPZD61N/+ mouse represents an authentic model of severe CMT1B affirming gain-of-glycosylation in P0 as a novel pathomechanism of disease.
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Affiliation(s)
- Francesca A Veneri
- Biology of Myelin Unit, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, 20132 Milan, Italy,Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DINOGMI), University of Genova, IRCCS AOU San Martino-IST, 16132 Genova, Italy
| | - Valeria Prada
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DINOGMI), University of Genova, IRCCS AOU San Martino-IST, 16132 Genova, Italy
| | - Rosa Mastrangelo
- Biology of Myelin Unit, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, 20132 Milan, Italy
| | - Cinzia Ferri
- Biology of Myelin Unit, Division of Genetics and Cell Biology, IRCCS Ospedale San Raffaele, 20132 Milan, Italy
| | - Lucilla Nobbio
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DINOGMI), University of Genova, IRCCS AOU San Martino-IST, 16132 Genova, Italy
| | - Mario Passalacqua
- Department of Experimental Medicine, University of Genova, 16132 Genova, Italy
| | - Maria Milanesi
- Experimental Oncology and Immunology, Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy
| | - Francesca Bianchi
- Movement Disorders Unit, Division of Neuroscience, IRCCS Ospedale San Raffaele, 20132 Milan, Italy
| | - Ubaldo Del Carro
- Movement Disorders Unit, Division of Neuroscience, IRCCS Ospedale San Raffaele, 20132 Milan, Italy
| | - Jean-Michel Vallat
- Department and Laboratory of Neurology, National Reference Center for ‘Rare Peripheral Neuropathies’, University Hospital of Limoges (CHU Limoges), Dupuytren Hospital, 87000 Limoges, France
| | - Phu Duong
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin–Madison, Madison, WI 53706, USA
| | - John Svaren
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin–Madison, Madison, WI 53706, USA
| | - Angelo Schenone
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DINOGMI), University of Genova, IRCCS AOU San Martino-IST, 16132 Genova, Italy,Department of Neurology, IRCCS Ospedale Policlinico San Martino, 16132 Genova, Italy
| | - Marina Grandis
- To whom correspondence should be addressed at: Department of Neurology, IRCCS Ospedale Policlinico San Martino, Largo Daneo 3, 16132 Genova, Italy. Tel: +39 010 3537562; (M.G.); San Raffaele Scientific Institute, DIBIT, via Olgettina 58, 20132 Milan, Italy. Tel: +39 02 26435307; (M.D.)
| | - Maurizio D’Antonio
- To whom correspondence should be addressed at: Department of Neurology, IRCCS Ospedale Policlinico San Martino, Largo Daneo 3, 16132 Genova, Italy. Tel: +39 010 3537562; (M.G.); San Raffaele Scientific Institute, DIBIT, via Olgettina 58, 20132 Milan, Italy. Tel: +39 02 26435307; (M.D.)
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27
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Elbaz B, Yang L, Vardy M, Isaac S, Rader BL, Kawaguchi R, Traka M, Woolf CJ, Renthal W, Popko B. Sensory neurons display cell-type-specific vulnerability to loss of neuron-glia interactions. Cell Rep 2022; 40:111130. [PMID: 35858549 PMCID: PMC9354470 DOI: 10.1016/j.celrep.2022.111130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 12/22/2021] [Accepted: 07/01/2022] [Indexed: 11/11/2022] Open
Abstract
Peripheral nervous system (PNS) injuries initiate transcriptional changes in glial cells and sensory neurons that promote axonal regeneration. While the factors that initiate the transcriptional changes in glial cells are well characterized, the full range of stimuli that initiate the response of sensory neurons remain elusive. Here, using a genetic model of glial cell ablation, we find that glial cell loss results in transient PNS demyelination without overt axonal loss. By profiling sensory ganglia at single-cell resolution, we show that glial cell loss induces a transcriptional injury response preferentially in proprioceptive and Aβ RA-LTMR neurons. The transcriptional response of sensory neurons to mechanical injury has been assumed to be a cell-autonomous response. By identifying a similar response in non-injured, demyelinated neurons, our study suggests that this represents a non-cell-autonomous transcriptional response of sensory neurons to glial cell loss and demyelination.
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Affiliation(s)
- Benayahu Elbaz
- Department of Neurology, Northwestern Feinberg School of Medicine, Chicago, IL, USA.
| | - Lite Yang
- Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, 60 Fenwood Road, Boston, MA 02115, USA
| | - Maia Vardy
- Department of Neurology, Northwestern Feinberg School of Medicine, Chicago, IL, USA
| | - Sara Isaac
- Department of Cell and Developmental Biology, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Braesen L Rader
- Department of Neurology, Northwestern Feinberg School of Medicine, Chicago, IL, USA
| | - Riki Kawaguchi
- Program in Neurogenetics, Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Maria Traka
- Department of Anatomy, College of Graduate Studies, Midwestern University, Downers Grove, IL, USA
| | - Clifford J Woolf
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, MA 02115, USA; F.M. Kirby Neurobiology Center, Boston Children's Hospital, 3 Blackfan Circle, Boston, MA 02115, USA
| | - William Renthal
- Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, 60 Fenwood Road, Boston, MA 02115, USA
| | - Brian Popko
- Department of Neurology, Northwestern Feinberg School of Medicine, Chicago, IL, USA.
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28
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Abstract
Schwann cells in the peripheral nervous system (PNS) are essential for the support and myelination of axons, ensuring fast and accurate communication between the central nervous system and the periphery. Schwann cells and related glia accompany innervating axons in virtually all tissues in the body, where they exhibit remarkable plasticity and the ability to modulate pathology in extraordinary, and sometimes surprising, ways. Here, we provide a brief overview of the various glial cell types in the PNS and describe the cornerstone cellular and molecular processes that enable Schwann cells to perform their canonical functions. We then dive into discussing exciting noncanonical functions of Schwann cells and related PNS glia, which include their role in organizing the PNS, in regulating synaptic activity and pain, in modulating immunity, in providing a pool of stem cells for different organs, and, finally, in influencing cancer.
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Affiliation(s)
- Carla Taveggia
- Axo-Glial Interaction Unit, Division of Neuroscience, IRCCS Ospedale San Raffaele, Milan, Italy;
| | - M. Laura Feltri
- Institute for Myelin and Glia Exploration, Departments of Biochemistry and Neurology, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York, USA
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29
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Chu TH, Baral K, Labit E, Rosin N, Sinha S, Umansky D, Alzahrani S, Rancourt D, Biernaskie J, Midha R. Comparison of human skin- and nerve-derived Schwann cells reveals many similarities and subtle genomic and functional differences. Glia 2022; 70:2131-2156. [PMID: 35796321 DOI: 10.1002/glia.24242] [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: 03/24/2022] [Revised: 06/24/2022] [Accepted: 06/24/2022] [Indexed: 11/08/2022]
Abstract
Skin is an easily accessible tissue and a rich source of Schwann cells (SCs). Toward potential clinical application of autologous SC therapies, we aim to improve the reliability and specificity of our protocol to obtain SCs from small skin samples. As well, to explore potential functional distinctions between skin-derived SCs (Sk-SCs) and nerve-derived SCs (N-SCs), we used single-cell RNA-sequencing and a series of in vitro and in vivo assays. Our results showed that Sk-SCs expressed typical SC markers. Single-cell sequencing of Sk- and N-SCs revealed an overwhelming overlap in gene expression with the exception of HLA genes which were preferentially up-regulated in Sk-SCs. In vitro, both cell types exhibited similar levels of proliferation, migration, uptake of myelin debris and readily associated with neurites when co-cultured with human iPSC-induced motor neurons. Both exhibited ensheathment of multiple neurites and early phase of myelination, especially in N-SCs. Interestingly, dorsal root ganglion (DRG) neurite outgrowth assay showed substantially more complexed neurite outgrowth in DRGs exposed to Sk-SC conditioned media compared to those from N-SCs. Multiplex ELISA array revealed shared growth factor profiles, but Sk-SCs expressed a higher level of VEGF. Transplantation of Sk- and N-SCs into injured peripheral nerve in nude rats and NOD-SCID mice showed close association of both SCs to regenerating axons. Myelination of rodent axons was observed infrequently by N-SCs, but absent in Sk-SC xenografts. Overall, our results showed that Sk-SCs share near-identical properties to N-SCs but with subtle differences that could potentially enhance their therapeutic utility.
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Affiliation(s)
- Tak-Ho Chu
- Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Kabita Baral
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Elodie Labit
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Nicole Rosin
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Sarthak Sinha
- Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Daniel Umansky
- Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
| | - Saud Alzahrani
- Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
| | - Derrick Rancourt
- Department of Biochemistry & Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,McCaig Institute for Bone and Joint Health, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Jeff Biernaskie
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Department of Comparative Biology and Experimental Medicine, Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Rajiv Midha
- Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
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30
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Wang H, Chen W, Dong Z, Xing G, Cui W, Yao L, Zou WJ, Robinson HL, Bian Y, Liu Z, Zhao K, Luo B, Gao N, Zhang H, Ren X, Yu Z, Meixiong J, Xiong WC, Mei L. A novel spinal neuron connection for heat sensation. Neuron 2022; 110:2315-2333.e6. [PMID: 35561677 DOI: 10.1016/j.neuron.2022.04.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 03/14/2022] [Accepted: 04/19/2022] [Indexed: 12/30/2022]
Abstract
Heat perception enables acute avoidance responses to prevent tissue damage and maintain body thermal homeostasis. Unlike other modalities, how heat signals are processed in the spinal cord remains unclear. By single-cell gene profiling, we identified ErbB4, a transmembrane tyrosine kinase, as a novel marker of heat-sensitive spinal neurons in mice. Ablating spinal ErbB4+ neurons attenuates heat sensation. These neurons receive monosynaptic inputs from TRPV1+ nociceptors and form excitatory synapses onto target neurons. Activation of ErbB4+ neurons enhances the heat response, while inhibition reduces the heat response. We showed that heat sensation is regulated by NRG1, an activator of ErbB4, and it involves dynamic activity of the tyrosine kinase that promotes glutamatergic transmission. Evidence indicates that the NRG1-ErbB4 signaling is also engaged in hypersensitivity of pathological pain. Together, these results identify a spinal neuron connection consisting of ErbB4+ neurons for heat sensation and reveal a regulatory mechanism by the NRG1-ErbB4 signaling.
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Affiliation(s)
- Hongsheng Wang
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Wenbing Chen
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Zhaoqi Dong
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Guanglin Xing
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Wanpeng Cui
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Lingling Yao
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Wen-Jun Zou
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Heath L Robinson
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Yaoyao Bian
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Zhipeng Liu
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Kai Zhao
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Bin Luo
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Nannan Gao
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Hongsheng Zhang
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Xiao Ren
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - Zheng Yu
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
| | - James Meixiong
- Solomon H. Snyder Department of Neuroscience and Medical Scientist Training Program, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Wen-Cheng Xiong
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA; Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH 44106, USA
| | - Lin Mei
- Department of Neurosciences, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA; Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH 44106, USA.
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31
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Bai Y, Treins C, Volpi VG, Scapin C, Ferri C, Mastrangelo R, Touvier T, Florio F, Bianchi F, Del Carro U, Baas FF, Wang D, Miniou P, Guedat P, Shy ME, D'Antonio M. Treatment with IFB-088 Improves Neuropathy in CMT1A and CMT1B Mice. Mol Neurobiol 2022; 59:4159-4178. [PMID: 35501630 PMCID: PMC9167212 DOI: 10.1007/s12035-022-02838-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 04/09/2022] [Indexed: 11/24/2022]
Abstract
Charcot-Marie-Tooth disease type 1A (CMT1A), caused by duplication of the peripheral myelin protein 22 (PMP22) gene, and CMT1B, caused by mutations in myelin protein zero (MPZ) gene, are the two most common forms of demyelinating CMT (CMT1), and no treatments are available for either. Prior studies of the MpzSer63del mouse model of CMT1B have demonstrated that protein misfolding, endoplasmic reticulum (ER) retention and activation of the unfolded protein response (UPR) contributed to the neuropathy. Heterozygous patients with an arginine to cysteine mutation in MPZ (MPZR98C) develop a severe infantile form of CMT1B which is modelled by MpzR98C/ + mice that also show ER stress and an activated UPR. C3-PMP22 mice are considered to effectively model CMT1A. Altered proteostasis, ER stress and activation of the UPR have been demonstrated in mice carrying Pmp22 mutations. To determine whether enabling the ER stress/UPR and readjusting protein homeostasis would effectively treat these models of CMT1B and CMT1A, we administered Sephin1/IFB-088/icerguestat, a UPR modulator which showed efficacy in the MpzS63del model of CMT1B, to heterozygous MpzR98C and C3-PMP22 mice. Mice were analysed by behavioural, neurophysiological, morphological and biochemical measures. Both MpzR98C/ + and C3-PMP22 mice improved in motor function and neurophysiology. Myelination, as demonstrated by g-ratios and myelin thickness, improved in CMT1B and CMT1A mice and markers of UPR activation returned towards wild-type values. Taken together, our results demonstrate the capability of IFB-088 to treat a second mouse model of CMT1B and a mouse model of CMT1A, the most common form of CMT. Given the recent benefits of IFB-088 treatment in amyotrophic lateral sclerosis and multiple sclerosis animal models, these data demonstrate its potential in managing UPR and ER stress for multiple mutations in CMT1 as well as in other neurodegenerative diseases.
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Affiliation(s)
- Yunhong Bai
- Department of Neurology, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | | | - Vera G Volpi
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute DIBIT, 20132, Milan, Italy
| | - Cristina Scapin
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute DIBIT, 20132, Milan, Italy
| | - Cinzia Ferri
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute DIBIT, 20132, Milan, Italy
| | - Rosa Mastrangelo
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute DIBIT, 20132, Milan, Italy
| | - Thierry Touvier
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute DIBIT, 20132, Milan, Italy
| | - Francesca Florio
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute DIBIT, 20132, Milan, Italy
| | - Francesca Bianchi
- Division of Neuroscience, San Raffaele Scientific Institute DIBIT, 20132, Milan, Italy
| | - Ubaldo Del Carro
- Division of Neuroscience, San Raffaele Scientific Institute DIBIT, 20132, Milan, Italy
| | - Frank F Baas
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - David Wang
- Department of Neurology, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | | | | | - Michael E Shy
- Department of Neurology, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Maurizio D'Antonio
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute DIBIT, 20132, Milan, Italy.
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32
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Park HJ, Tsai E, Huang D, Weaver M, Frick L, Alcantara A, Moran JJ, Patzig J, Melendez-Vasquez CV, Crabtree GR, Feltri ML, Svaren J, Casaccia P. ACTL6a coordinates axonal caliber recognition and myelination in the peripheral nerve. iScience 2022; 25:104132. [PMID: 35434551 PMCID: PMC9010646 DOI: 10.1016/j.isci.2022.104132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 01/29/2022] [Accepted: 03/17/2022] [Indexed: 11/12/2022] Open
Abstract
Cells elaborate transcriptional programs in response to external signals. In the peripheral nerves, Schwann cells (SC) sort axons of given caliber and start the process of wrapping their membrane around them. We identify Actin-like protein 6a (ACTL6a), part of SWI/SNF chromatin remodeling complex, as critical for the integration of axonal caliber recognition with the transcriptional program of myelination. Nuclear levels of ACTL6A in SC are increased by contact with large caliber axons or nanofibers, and result in the eviction of repressive histone marks to facilitate myelination. Without Actl6a the SC are unable to coordinate caliber recognition and myelin production. Peripheral nerves in knockout mice display defective radial sorting, hypo-myelination of large caliber axons, and redundant myelin around small caliber axons, resulting in a clinical motor phenotype. Overall, this suggests that ACTL6A is a key component of the machinery integrating external signals for proper myelination of the peripheral nerve. ACTL6a levels in Schwann cells respond to stiffness and caliber of PLA nanofibers ACTL6a integrates axonal caliber recognition signals with Schwann cells transcriptome ACTL6a null mice have thin myelin on large axons and redundant myelin on small axons Mice lacking ACTL6a in Schwann cells show severe clinical symptoms
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Affiliation(s)
- Hye-Jin Park
- Advanced Science Research Center (ASRC) at The Graduate Center of the City University of New York (CUNY), New York, NY 10031, USA
| | - Eric Tsai
- Advanced Science Research Center (ASRC) at The Graduate Center of the City University of New York (CUNY), New York, NY 10031, USA.,Graduate Program in Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Dennis Huang
- Advanced Science Research Center (ASRC) at The Graduate Center of the City University of New York (CUNY), New York, NY 10031, USA.,Graduate Program in Biology, Graduate Center of CUNY, New York, NY 10016, USA
| | - Michael Weaver
- Hunter James Kelly Research Institute, Departments of Biochemistry and Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14203, USA
| | - Luciana Frick
- Hunter James Kelly Research Institute, Departments of Biochemistry and Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14203, USA
| | - Ace Alcantara
- Graduate Program in Biology, Graduate Center of CUNY, New York, NY 10016, USA.,Hunter College, Department of Biological Sciences, New York, NY 10065, USA
| | - John J Moran
- Waisman Center and Department of Comparative Biosciences, University of Wisconsin, Madison, WI 53705, USA
| | - Julia Patzig
- Advanced Science Research Center (ASRC) at The Graduate Center of the City University of New York (CUNY), New York, NY 10031, USA
| | - Carmen V Melendez-Vasquez
- Graduate Program in Biology, Graduate Center of CUNY, New York, NY 10016, USA.,Hunter College, Department of Biological Sciences, New York, NY 10065, USA
| | - Gerald R Crabtree
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - M L Feltri
- Hunter James Kelly Research Institute, Departments of Biochemistry and Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14203, USA
| | - John Svaren
- Waisman Center and Department of Comparative Biosciences, University of Wisconsin, Madison, WI 53705, USA
| | - Patrizia Casaccia
- Advanced Science Research Center (ASRC) at The Graduate Center of the City University of New York (CUNY), New York, NY 10031, USA.,Graduate Program in Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.,Graduate Program in Biology, Graduate Center of CUNY, New York, NY 10016, USA
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33
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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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34
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Jessen KR, Mirsky R. The Role of c-Jun and Autocrine Signaling Loops in the Control of Repair Schwann Cells and Regeneration. Front Cell Neurosci 2022; 15:820216. [PMID: 35221918 PMCID: PMC8863656 DOI: 10.3389/fncel.2021.820216] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 12/30/2021] [Indexed: 12/12/2022] Open
Abstract
After nerve injury, both Schwann cells and neurons switch to pro-regenerative states. For Schwann cells, this involves reprogramming of myelin and Remak cells to repair Schwann cells that provide the signals and mechanisms needed for the survival of injured neurons, myelin clearance, axonal regeneration and target reinnervation. Because functional repair cells are essential for regeneration, it is unfortunate that their phenotype is not robust. Repair cell activation falters as animals get older and the repair phenotype fades during chronic denervation. These malfunctions are important reasons for the poor outcomes after nerve damage in humans. This review will discuss injury-induced Schwann cell reprogramming and the concept of the repair Schwann cell, and consider the molecular control of these cells with emphasis on c-Jun. This transcription factor is required for the generation of functional repair cells, and failure of c-Jun expression is implicated in repair cell failures in older animals and during chronic denervation. Elevating c-Jun expression in repair cells promotes regeneration, showing in principle that targeting repair cells is an effective way of improving nerve repair. In this context, we will outline the emerging evidence that repair cells are sustained by autocrine signaling loops, attractive targets for interventions aimed at promoting regeneration.
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Affiliation(s)
- Kristjan R. Jessen
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
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35
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Notch Signal Mediates the Cross-Interaction between M2 Muscarinic Acetylcholine Receptor and Neuregulin/ErbB Pathway: Effects on Schwann Cell Proliferation. Biomolecules 2022; 12:biom12020239. [PMID: 35204740 PMCID: PMC8961597 DOI: 10.3390/biom12020239] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 01/26/2022] [Accepted: 01/27/2022] [Indexed: 02/01/2023] Open
Abstract
The cross-talk between axon and glial cells during development and in adulthood is mediated by several molecules. Among them are neurotransmitters and their receptors, which are involved in the control of myelinating and non-myelinating glial cell development and physiology. Our previous studies largely demonstrate the functional expression of cholinergic muscarinic receptors in Schwann cells. In particular, the M2 muscarinic receptor subtype, the most abundant cholinergic receptor expressed in Schwann cells, inhibits cell proliferation downregulating proteins expressed in the immature phenotype and triggers promyelinating differentiation genes. In this study, we analysed the in vitro modulation of the Neuregulin-1 (NRG1)/erbB pathway, mediated by the M2 receptor activation, through the selective agonist arecaidine propargyl ester (APE). M2 agonist treatment significantly downregulates NRG1 and erbB receptors expression, both at transcriptional and protein level, and causes the internalization and intracellular accumulation of the erbB2 receptor. Additionally, starting from our previous results concerning the negative modulation of Notch-active fragment NICD by M2 receptor activation, in this work, we clearly demonstrate that the M2 receptor subtype inhibits erbB2 receptors by Notch-1/NICD downregulation. Our data, together with our previous results, demonstrate the existence of a cross-interaction between the M2 receptor and NRG1/erbB pathway-Notch1 mediated, and that it is responsible for the modulation of Schwann cell proliferation/differentiation.
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36
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Negro S, Pirazzini M, Rigoni M. Models and methods to study Schwann cells. J Anat 2022; 241:1235-1258. [PMID: 34988978 PMCID: PMC9558160 DOI: 10.1111/joa.13606] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 11/26/2021] [Accepted: 11/29/2021] [Indexed: 12/22/2022] Open
Abstract
Schwann cells (SCs) are fundamental components of the peripheral nervous system (PNS) of all vertebrates and play essential roles in development, maintenance, function, and regeneration of peripheral nerves. There are distinct populations of SCs including: (1) myelinating SCs that ensheath axons by a specialized plasma membrane, called myelin, which enhances the conduction of electric impulses; (2) non‐myelinating SCs, including Remak SCs, which wrap bundles of multiple axons of small caliber, and perysinaptic SCs (PSCs), associated with motor axon terminals at the neuromuscular junction (NMJ). All types of SCs contribute to PNS regeneration through striking morphological and functional changes in response to nerve injury, are affected in peripheral neuropathies and show abnormalities and a diminished plasticity during aging. Therefore, methodological approaches to study and manipulate SCs in physiological and pathophysiological conditions are crucial to expand the present knowledge on SC biology and to devise new therapeutic strategies to counteract neurodegenerative conditions and age‐derived denervation. We present here an updated overview of traditional and emerging methodologies for the study of SCs for scientists approaching this research field.
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Affiliation(s)
- Samuele Negro
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Marco Pirazzini
- Department of Biomedical Sciences, University of Padua, Padua, Italy.,CIR-Myo, Centro Interdipartimentale di Ricerca di Miologia, University of Padua, Padova, Italy
| | - Michela Rigoni
- Department of Biomedical Sciences, University of Padua, Padua, Italy.,CIR-Myo, Centro Interdipartimentale di Ricerca di Miologia, University of Padua, Padova, Italy
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37
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Four Seasons for Schwann Cell Biology, Revisiting Key Periods: Development, Homeostasis, Repair, and Aging. Biomolecules 2021; 11:biom11121887. [PMID: 34944531 PMCID: PMC8699407 DOI: 10.3390/biom11121887] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 12/08/2021] [Accepted: 12/10/2021] [Indexed: 01/28/2023] Open
Abstract
Like the seasons of the year, all natural things happen in stages, going through adaptations when challenged, and Schwann cells are a great example of that. During maturation, these cells regulate several steps in peripheral nervous system development. The Spring of the cell means the rise and bloom through organized stages defined by time-dependent regulation of factors and microenvironmental influences. Once matured, the Summer of the cell begins: a high energy stage focused on maintaining adult homeostasis. The Schwann cell provides many neuron-glia communications resulting in the maintenance of synapses. In the peripheral nervous system, Schwann cells are pivotal after injuries, balancing degeneration and regeneration, similarly to when Autumn comes. Their ability to acquire a repair phenotype brings the potential to reconnect axons to targets and regain function. Finally, Schwann cells age, not only by growing old, but also by imposed environmental cues, like loss of function induced by pathologies. The Winter of the cell presents as reduced activity, especially regarding their role in repair; this reflects on the regenerative potential of older/less healthy individuals. This review gathers essential information about Schwann cells in different stages, summarizing important participation of this intriguing cell in many functions throughout its lifetime.
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38
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Pisciotta C, Saveri P, Pareyson D. Challenges in Treating Charcot-Marie-Tooth Disease and Related Neuropathies: Current Management and Future Perspectives. Brain Sci 2021; 11:1447. [PMID: 34827446 PMCID: PMC8615778 DOI: 10.3390/brainsci11111447] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 02/06/2023] Open
Abstract
There is still no effective drug treatment available for Charcot-Marie-Tooth neuropathies (CMT). Current management relies on rehabilitation therapy, surgery for skeletal deformities, and symptomatic treatment of pain; fatigue and cramps are frequent complaints that are difficult to treat. The challenge is to find disease-modifying therapies. Several approaches, including gene silencing, to counteract the PMP22 gene overexpression in the most frequent CMT1A type are under investigation. PXT3003 is the compound in the most advanced phase for CMT1A, as a second-phase III trial is ongoing. Gene therapy to substitute defective genes or insert novel ones and compounds acting on pathways important for different CMT types are being developed and tested in animal models. Modulation of the Neuregulin pathway determining myelin thickness is promising for both hypo-demyelinating and hypermyelinating neuropathies; intervention on Unfolded Protein Response seems effective for rescuing misfolded myelin proteins such as P0 in CMT1B. HDAC6 inhibitors improved axonal transport and ameliorated phenotypes in different CMT models. Other potential therapeutic strategies include targeting macrophages, lipid metabolism, and Nav1.8 sodium channel in demyelinating CMT and the P2X7 receptor, which regulates calcium influx into Schwann cells, in CMT1A. Further approaches are aimed at correcting metabolic abnormalities, including the accumulation of sorbitol caused by biallelic mutations in the sorbitol dehydrogenase (SORD) gene and of neurotoxic glycosphingolipids in HSN1.
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Affiliation(s)
| | | | - Davide Pareyson
- Unit of Rare Neurodegenerative and Neurometabolic Diseases, Department of Clinical Neurosciences, Fondazione IRCCS Istituto Neurologico Carlo Besta, Via Celoria 11, 20133 Milan, Italy; (C.P.); (P.S.)
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39
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Mammel AE, Delgado KC, Chin AL, Condon AF, Hill JQ, Aicher SA, Wang Y, Fedorov LM, Robinson FL. Distinct roles for the Charcot-Marie-tooth disease-causing endosomal regulators Mtmr5 and Mtmr13 in axon radial sorting and Schwann cell myelination. Hum Mol Genet 2021; 31:1216-1229. [PMID: 34718573 DOI: 10.1093/hmg/ddab311] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 09/29/2021] [Accepted: 10/19/2021] [Indexed: 11/12/2022] Open
Abstract
The form of Charcot-Marie-Tooth type 4B (CMT4B) disease caused by mutations in myotubularin-related 5 (MTMR5; also called SET Binding Factor 1; SBF1) shows a spectrum of axonal and demyelinating nerve phenotypes. This contrasts with the CMT4B subtypes caused by MTMR2 or MTMR13 (SBF2) mutations, which are characterized by myelin outfoldings and classic demyelination. Thus, it is unclear whether MTMR5 plays an analogous or distinct role from that of its homolog, MTMR13, in the peripheral nervous system (PNS). MTMR5 and MTMR13 are pseudophosphatases predicted to regulate endosomal trafficking by activating Rab GTPases and binding to the phosphoinositide 3-phosphatase MTMR2. In the mouse PNS, Mtmr2 was required to maintain wild type levels of Mtmr5 and Mtmr13, suggesting that these factors function in discrete protein complexes. Genetic elimination of both Mtmr5 and Mtmr13 in mice led to perinatal lethality, indicating that the two proteins have partially redundant functions during embryogenesis. Loss of Mtmr5 in mice did not cause CMT4B-like myelin outfoldings. However, adult Mtmr5-/- mouse nerves contained fewer myelinated axons than control nerves, likely as a result of axon radial sorting defects. Consistently, Mtmr5 levels were highest during axon radial sorting and fell sharply after postnatal day seven. Our findings suggest that Mtmr5 and Mtmr13 ensure proper axon radial sorting and Schwann cell myelination, respectively, perhaps through their direct interactions with Mtmr2. This study enhances our understanding of the non-redundant roles of the endosomal regulators MTMR5 and MTMR13 during normal peripheral nerve development and disease.
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Affiliation(s)
- Anna E Mammel
- The Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA.,Cell, Developmental & Cancer Biology Graduate Program, Oregon Health & Science University
| | - Katherine C Delgado
- The Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Andrea L Chin
- The Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Alec F Condon
- The Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA.,Neuroscience Graduate Program, Oregon Health & Science University
| | - Jo Q Hill
- Department of Physiology and Pharmacology, Oregon Health & Science University
| | - Sue A Aicher
- Department of Physiology and Pharmacology, Oregon Health & Science University
| | - Yingming Wang
- OHSU Transgenic Mouse Models Shared Resource, Knight Cancer Institute, Oregon Health & Science University
| | - Lev M Fedorov
- OHSU Transgenic Mouse Models Shared Resource, Knight Cancer Institute, Oregon Health & Science University
| | - Fred L Robinson
- The Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA.,Vollum Institute, Oregon Health & Science University
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40
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Follis RM, Tep C, Genaro-Mattos TC, Kim ML, Ryu JC, Morrison VE, Chan JR, Porter N, Carter BD, Yoon SO. Metabolic Control of Sensory Neuron Survival by the p75 Neurotrophin Receptor in Schwann Cells. J Neurosci 2021; 41:8710-8724. [PMID: 34507952 PMCID: PMC8528492 DOI: 10.1523/jneurosci.3243-20.2021] [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: 12/31/2020] [Revised: 08/28/2021] [Accepted: 08/30/2021] [Indexed: 11/21/2022] Open
Abstract
We report that the neurotrophin receptor p75 contributes to sensory neuron survival through the regulation of cholesterol metabolism in Schwann cells. Selective deletion of p75 in mouse Schwann cells of either sex resulted in a 30% loss of dorsal root ganglia (DRG) neurons and diminished thermal sensitivity. P75 regulates Schwann cell cholesterol biosynthesis in response to BDNF, forming a co-receptor complex with ErbB2 and activating ErbB2-mediated stimulation of sterol regulatory element binding protein 2 (SREBP2), a master regulator of cholesterol synthesis. Schwann cells lacking p75 exhibited decreased activation of SREBP2 and a reduction in 7-dehydrocholesterol (7-DHC) reductase (DHCR7) expression, resulting in accumulation of the neurotoxic intermediate, 7-dehyrocholesterol in the sciatic nerve. Restoration of DHCR7 in p75 null Schwann cells in mice significantly attenuated DRG neuron loss. Together, these results reveal a mechanism by which the disruption of lipid metabolism in glial cells negatively influences sensory neuron survival, which has implications for a wide range of peripheral neuropathies.SIGNIFICANCE STATEMENT Although expressed in Schwann cells, the role of p75 in myelination has remained unresolved in part because of its dual expression in sensory neurons that Schwann cells myelinate. When p75 was deleted selectively among Schwann cells, myelination was minimally affected, while sensory neuron survival was reduced by 30%. The phenotype is mainly due to dysregulation of cholesterol biosynthesis in p75-deficient Schwann cells, leading to an accumulation of neurotoxic cholesterol precursor, 7-dehydrocholesterol (7-DHC). Mechanism-wise, we discovered that in response to BDNF, p75 recruits and activates ErbB2 independently of ErbB3, thereby stimulating the master regulator, sterol regulatory element binding protein 2 (SREBP2). These results together highlight a novel role of p75 in Schwann cells in regulating DRG neuron survival by orchestrating proper cholesterol metabolism.
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Affiliation(s)
- Rose M Follis
- Department of Biochemistry, Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Chhavy Tep
- Department of Biological Chemistry and Pharmacology, Ohio State University, Columbus, Ohio
| | - Thiago C Genaro-Mattos
- Department of Chemistry, Vanderbilt University School of Arts and Sciences, Nashville, Tennessee 37232
| | - Mi Lyang Kim
- Department of Biological Chemistry and Pharmacology, Ohio State University, Columbus, Ohio
| | - Jae Cheon Ryu
- Department of Biological Chemistry and Pharmacology, Ohio State University, Columbus, Ohio
| | - Vivianne E Morrison
- Department of Biochemistry, Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Jonah R Chan
- Department of Neurology, University of California San Francisco, San Francisco, California 94158
| | - Ned Porter
- Department of Chemistry, Vanderbilt University School of Arts and Sciences, Nashville, Tennessee 37232
| | - Bruce D Carter
- Department of Biochemistry, Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Sung Ok Yoon
- Department of Biological Chemistry and Pharmacology, Ohio State University, Columbus, Ohio
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41
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Ki SM, Jeong HS, Lee JE. Primary Cilia in Glial Cells: An Oasis in the Journey to Overcoming Neurodegenerative Diseases. Front Neurosci 2021; 15:736888. [PMID: 34658775 PMCID: PMC8514955 DOI: 10.3389/fnins.2021.736888] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 08/31/2021] [Indexed: 12/29/2022] Open
Abstract
Many neurodegenerative diseases have been associated with defects in primary cilia, which are cellular organelles involved in diverse cellular processes and homeostasis. Several types of glial cells in both the central and peripheral nervous systems not only support the development and function of neurons but also play significant roles in the mechanisms of neurological disease. Nevertheless, most studies have focused on investigating the role of primary cilia in neurons. Accordingly, the interest of recent studies has expanded to elucidate the role of primary cilia in glial cells. Correspondingly, several reports have added to the growing evidence that most glial cells have primary cilia and that impairment of cilia leads to neurodegenerative diseases. In this review, we aimed to understand the regulatory mechanisms of cilia formation and the disease-related functions of cilia, which are common or specific to each glial cell. Moreover, we have paid close attention to the signal transduction and pathological mechanisms mediated by glia cilia in representative neurodegenerative diseases. Finally, we expect that this field of research will clarify the mechanisms involved in the formation and function of glial cilia to provide novel insights and ideas for the treatment of neurodegenerative diseases in the future.
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Affiliation(s)
- Soo Mi Ki
- Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul, South Korea
| | - Hui Su Jeong
- Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul, South Korea
| | - Ji Eun Lee
- Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul, South Korea.,Samsung Medical Center, Samsung Biomedical Research Institute, Seoul, South Korea
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42
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Previtali SC. Peripheral Nerve Development and the Pathogenesis of Peripheral Neuropathy: the Sorting Point. Neurotherapeutics 2021; 18:2156-2168. [PMID: 34244926 PMCID: PMC8804061 DOI: 10.1007/s13311-021-01080-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/26/2021] [Indexed: 12/12/2022] Open
Abstract
Nerve development requires a coordinated sequence of events and steps to be accomplished for the generation of functional peripheral nerves to convey sensory and motor signals. Any abnormality during development may result in pathological structure and function of the nerve, which evolves in peripheral neuropathy. In this review, we will briefly describe different steps of nerve development while we will mostly focus on the molecular mechanisms involved in radial sorting of axons, one of these nerve developmental steps. We will summarize current knowledge of molecular pathways so far reported in radial sorting and their possible interactions. Finally, we will describe how disruption of these pathways may result in human neuropathies.
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Affiliation(s)
- Stefano C Previtali
- Neuromuscular Repair Unit, InSpe (Institute of Experimental Neurology) and Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy.
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43
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Abstract
Myelin is a key evolutionary specialization and adaptation of vertebrates formed by the plasma membrane of glial cells, which insulate axons in the nervous system. Myelination not only allows rapid and efficient transmission of electric impulses in the axon by decreasing capacitance and increasing resistance but also influences axonal metabolism and the plasticity of neural circuits. In this review, we will focus on Schwann cells, the glial cells which form myelin in the peripheral nervous system. Here, we will describe the main extrinsic and intrinsic signals inducing Schwann cell differentiation and myelination and how myelin biogenesis is achieved. Finally, we will also discuss how the study of human disorders in which molecules and pathways relevant for myelination are altered has enormously contributed to the current knowledge on myelin biology.
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Affiliation(s)
- Alessandra Bolino
- Human Inherited Neuropathies Unit, Institute of Experimental Neurology INSPE, Division of Neuroscience, IRCCS Ospedale San Raffaele, Via Olgettina 60, 20132, Milan, Italy.
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44
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Abstract
Demyelinating forms of Charcot-Marie-Tooth disease (CMT) are genetically and phenotypically heterogeneous and result from highly diverse biological mechanisms including gain of function (including dominant negative effects) and loss of function. While no definitive treatment is currently available, rapid advances in defining the pathomechanisms of demyelinating CMT have led to promising pre-clinical studies, as well as emerging clinical trials. Especially promising are the recently completed pre-clinical genetic therapy studies in PMP-22, GJB1, and SH3TC2-associated neuropathies, particularly given the success of similar approaches in humans with spinal muscular atrophy and transthyretin familial polyneuropathy. This article focuses on neuropathies related to mutations in PMP-22, MPZ, and GJB1, which together comprise the most common forms of demyelinating CMT, as well as on select rarer forms for which promising treatment targets have been identified. Clinical characteristics and pathomechanisms are reviewed in detail, with emphasis on therapeutically targetable biological pathways. Also discussed are the challenges facing the CMT research community in its efforts to advance the rapidly evolving biological insights to effective clinical trials. These considerations include the limitations of currently available animal models, the need for personalized medicine approaches/allele-specific interventions for select forms of demyelinating CMT, and the increasing demand for optimal clinical outcome assessments and objective biomarkers.
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Affiliation(s)
- Vera Fridman
- Department of Neurology, University of Colorado Anschutz Medical Campus, 12631 E 17th Avenue, Mailstop B185, Room 5113C, Aurora, CO, 80045, USA.
| | - Mario A Saporta
- Department of Neurology, University of Miami Miller School of Medicine, Miami, FL, USA
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45
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Animal Models as a Tool to Design Therapeutical Strategies for CMT-like Hereditary Neuropathies. Brain Sci 2021; 11:brainsci11091237. [PMID: 34573256 PMCID: PMC8465478 DOI: 10.3390/brainsci11091237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 09/05/2021] [Accepted: 09/07/2021] [Indexed: 02/07/2023] Open
Abstract
Since ancient times, animal models have provided fundamental information in medical knowledge. This also applies for discoveries in the field of inherited peripheral neuropathies (IPNs), where they have been instrumental for our understanding of nerve development, pathogenesis of neuropathy, molecules and pathways involved and to design potential therapies. In this review, we briefly describe how animal models have been used in ancient medicine until the use of rodents as the prevalent model in present times. We then travel along different examples of how rodents have been used to improve our understanding of IPNs. We do not intend to describe all discoveries and animal models developed for IPNs, but just to touch on a few arbitrary and paradigmatic examples, taken from our direct experience or from literature. The idea is to show how strategies have been developed to finally arrive to possible treatments for IPNs.
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46
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Markworth R, Bähr M, Burk K. Held Up in Traffic-Defects in the Trafficking Machinery in Charcot-Marie-Tooth Disease. Front Mol Neurosci 2021; 14:695294. [PMID: 34483837 PMCID: PMC8415527 DOI: 10.3389/fnmol.2021.695294] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 07/23/2021] [Indexed: 12/13/2022] Open
Abstract
Charcot-Marie-Tooth disease (CMT), also known as motor and sensory neuropathy, describes a clinically and genetically heterogenous group of disorders affecting the peripheral nervous system. CMT typically arises in early adulthood and is manifested by progressive loss of motor and sensory functions; however, the mechanisms leading to the pathogenesis are not fully understood. In this review, we discuss disrupted intracellular transport as a common denominator in the pathogenesis of different CMT subtypes. Intracellular transport via the endosomal system is essential for the delivery of lipids, proteins, and organelles bidirectionally to synapses and the soma. As neurons of the peripheral nervous system are amongst the longest neurons in the human body, they are particularly susceptible to damage of the intracellular transport system, leading to a loss in axonal integrity and neuronal death. Interestingly, defects in intracellular transport, both in neurons and Schwann cells, have been found to provoke disease. This review explains the mechanisms of trafficking and subsequently summarizes and discusses the latest findings on how defects in trafficking lead to CMT. A deeper understanding of intracellular trafficking defects in CMT will expand our understanding of CMT pathogenesis and will provide novel approaches for therapeutic treatments.
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Affiliation(s)
- Ronja Markworth
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany.,Center for Biostructural Imaging of Neurodegeneration, Göttingen, Germany
| | - Mathias Bähr
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Katja Burk
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany.,Center for Biostructural Imaging of Neurodegeneration, Göttingen, Germany
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47
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VerPlank JJS, Gawron J, Silvestri NJ, Feltri ML, Wrabetz L, Goldberg AL. Raising cGMP restores proteasome function and myelination in mice with a proteotoxic neuropathy. Brain 2021; 145:168-178. [PMID: 34382059 DOI: 10.1093/brain/awab249] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 05/12/2021] [Accepted: 06/16/2021] [Indexed: 11/14/2022] Open
Abstract
Agents that raise cGMP by activating Protein Kinase G increase 26S proteasome activities, protein ubiquitination, and degradation of misfolded proteins. Therefore, they may be useful in treating neurodegenerative and other diseases caused by an accumulation of misfolded proteins. Mutations in myelin protein zero (MPZ) cause the peripheral neuropathy Charcot Marie Tooth 1B (CMT1B). In peripheral nerves of a mouse model of CMT1B, where the mutant MPZS63del is expressed, proteasome activities are reduced, mutant MPZS63del and polyubiquitinated proteins accumulate, and the Unfolded Protein Response (p-eif2 α) is induced. In HEK293 cells, raising cGMP stimulated ubiquitination and degradation of MPZS63del, but not of MPZWT. Treating S63del mice with the phosphodiesterase 5 inhibitor, sildenafil, to raise cGMP increased proteasome activity in sciatic nerves and reduced the levels of polyubiquitinated proteins, the proteasome reporter ubG76V-GFP, and p-elF2α. Furthermore, sildenafil treatment reduced the number of amyelinated axons, and increased myelin thickness and nerve conduction velocity in sciatic nerves. Thus, agents that raise cGMP, including ones widely used in medicine, may be useful therapies for CMT1B and other proteotoxic diseases.
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Affiliation(s)
- Jordan J S VerPlank
- Harvard Medical School, Blavatnik Institute, Department of Cell Biology, Boston, MA, 02115, USA.,Hunter James Kelly Research Institute, Departments of Biochemistry and Neurology, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York 14203, USA
| | - Joseph Gawron
- Hunter James Kelly Research Institute, Departments of Biochemistry and Neurology, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York 14203, USA
| | - Nicholas J Silvestri
- Hunter James Kelly Research Institute, Departments of Biochemistry and Neurology, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York 14203, USA
| | - M Laura Feltri
- Hunter James Kelly Research Institute, Departments of Biochemistry and Neurology, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York 14203, USA
| | - Lawrence Wrabetz
- Hunter James Kelly Research Institute, Departments of Biochemistry and Neurology, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, New York 14203, USA
| | - Alfred L Goldberg
- Harvard Medical School, Blavatnik Institute, Department of Cell Biology, Boston, MA, 02115, USA
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48
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Tan C, Yang C, Liu H, Tang C, Huang S. Effect of Schwann cell transplantation combined with electroacupuncture on axonal regeneration and remyelination in rats with spinal cord injury. Anat Rec (Hoboken) 2021; 304:2506-2520. [PMID: 34319000 DOI: 10.1002/ar.24721] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 05/26/2021] [Accepted: 06/16/2021] [Indexed: 11/08/2022]
Abstract
Axonal impairment and demyelination after compressed spinal cord injury lead to serious neurological dysfunction. Increasing studies have suggested that Schwann cells (SCs) transplantation is a reliable, effective, and promising method for treating spinal cord injury. However, single SCs transplantation is insufficient to promote the full recovery of neurological function. Additional approaches are required to support SCs transplantation as a treatment for spinal cord injury. In the study, we investigated whether the combination of electroacupuncture (EA) and SCs transplantation was a reliable intervention for spinal cord injury. We found that rats in the combination group had significantly higher functional locomotor scores than those received single treatment. By immunostaining, we found EA can not only improve survival and proliferation of transplanted SCs but also inhibit SC apoptosis and block the formation of an astrocytic scar. Additionally, EA promoted regenerated axons extending "bullet-shaped" growth cones into the lesion. Remarkably, EA can modify astrogliosis to promote axonal regeneration following SCs transplantation through inducing extension of astrocytic processes in the SCs graft interface. More importantly, the combination of SCs engraftment and EA can enhance corticospinal-tract axonal regeneration and remyelination after spinal cord injury through up-regulating neuregulin 1 type III in SCs and its downstream signaling mediators. Thus, it is concluded that SCs effectively promote axonal recovery after spinal cord injury when combined with EA stimulation. The experimental results have reinforced the theoretical basis of EA for its clinical efficacy in patients with spinal cord injury and merited further investigation for potential clinical application.
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Affiliation(s)
- Chengfang Tan
- Traditional Chinese Medicine College, Chongqing Medical University, Chongqing, China
| | - Cheng Yang
- Traditional Chinese Medicine College, Chongqing Medical University, Chongqing, China
| | - Hui Liu
- Institute of Neuroscience, Chongqing Medical University, Chongqing, China
| | - Chenglin Tang
- Traditional Chinese Medicine College, Chongqing Medical University, Chongqing, China
| | - Siqin Huang
- Traditional Chinese Medicine College, Chongqing Medical University, Chongqing, China
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49
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Kong L, Valdivia DO, Simon CM, Hassinan CW, Delestrée N, Ramos DM, Park JH, Pilato CM, Xu X, Crowder M, Grzyb CC, King ZA, Petrillo M, Swoboda KJ, Davis C, Lutz CM, Stephan AH, Zhao X, Weetall M, Naryshkin NA, Crawford TO, Mentis GZ, Sumner CJ. Impaired prenatal motor axon development necessitates early therapeutic intervention in severe SMA. Sci Transl Med 2021; 13:13/578/eabb6871. [PMID: 33504650 DOI: 10.1126/scitranslmed.abb6871] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 09/18/2020] [Indexed: 12/21/2022]
Abstract
Gene replacement and pre-mRNA splicing modifier therapies represent breakthrough gene targeting treatments for the neuromuscular disease spinal muscular atrophy (SMA), but mechanisms underlying variable efficacy of treatment are incompletely understood. Our examination of severe infantile onset human SMA tissues obtained at expedited autopsy revealed persistence of developmentally immature motor neuron axons, many of which are actively degenerating. We identified similar features in a mouse model of severe SMA, in which impaired radial growth and Schwann cell ensheathment of motor axons began during embryogenesis and resulted in reduced acquisition of myelinated axons that impeded motor axon function neonatally. Axons that failed to ensheath degenerated rapidly postnatally, specifically releasing neurofilament light chain protein into the blood. Genetic restoration of survival motor neuron protein (SMN) expression in mouse motor neurons, but not in Schwann cells or muscle, improved SMA motor axon development and maintenance. Treatment with small-molecule SMN2 splice modifiers beginning immediately after birth in mice increased radial growth of the already myelinated axons, but in utero treatment was required to restore axonal growth and associated maturation, prevent subsequent neonatal axon degeneration, and enhance motor axon function. Together, these data reveal a cellular basis for the fulminant neonatal worsening of patients with infantile onset SMA and identify a temporal window for more effective treatment. These findings suggest that minimizing treatment delay is critical to achieve optimal therapeutic efficacy.
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Affiliation(s)
- Lingling Kong
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - David O Valdivia
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Christian M Simon
- Center for Motor Neuron Biology and Disease, Department of Pathology and Cell Biology, Columbia University, New York, NY 10032, USA
| | - Cera W Hassinan
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Nicolas Delestrée
- Center for Motor Neuron Biology and Disease, Department of Pathology and Cell Biology, Columbia University, New York, NY 10032, USA
| | - Daniel M Ramos
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jae Hong Park
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Celeste M Pilato
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Xixi Xu
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Melissa Crowder
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Chloe C Grzyb
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Zachary A King
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | | | - Kathryn J Swoboda
- Center for Genomic Medicine, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Crystal Davis
- Genetic Resource Science, The Jackson Laboratory, Bar Harbor, ME 04609, USA
| | - Cathleen M Lutz
- Genetic Resource Science, The Jackson Laboratory, Bar Harbor, ME 04609, USA
| | - Alexander H Stephan
- F. Hoffmann-La Roche Ltd., pRED, Pharma & Early Development, Roche Innovation Center Basel, Basel CH-4070, Switzerland
| | - Xin Zhao
- PTC Therapeutics, 100 Corporate Court, South Plainfield, NJ 07080, USA
| | - Marla Weetall
- PTC Therapeutics, 100 Corporate Court, South Plainfield, NJ 07080, USA
| | | | - Thomas O Crawford
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.,Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - George Z Mentis
- Center for Motor Neuron Biology and Disease, Department of Pathology and Cell Biology, Columbia University, New York, NY 10032, USA.,Department of Neurology, Columbia University, New York, NY 10032, USA
| | - Charlotte J Sumner
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA. .,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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50
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Ishii A, Furusho M, Bansal R. Mek/ERK1/2-MAPK and PI3K/Akt/mTOR signaling plays both independent and cooperative roles in Schwann cell differentiation, myelination and dysmyelination. Glia 2021; 69:2429-2446. [PMID: 34157170 DOI: 10.1002/glia.24049] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 04/29/2021] [Accepted: 06/04/2021] [Indexed: 01/15/2023]
Abstract
Multiple signals are involved in the regulation of developmental myelination by Schwann cells and in the maintenance of a normal myelin homeostasis throughout adult life, preserving the integrity of the axons in the PNS. Recent studies suggest that Mek/ERK1/2-MAPK and PI3K/Akt/mTOR intracellular signaling pathways play important, often overlapping roles in the regulation of myelination in the PNS. In addition, hyperactivation of these signaling pathways in Schwann cells leads to a late onset of various pathological changes in the sciatic nerves. However, it remains poorly understood whether these pathways function independently or sequentially or converge using a common mechanism to facilitate Schwann cell differentiation and myelin growth during development and in causing pathological changes in the adult animals. To address these questions, we analyzed multiple genetically modified mice using simultaneous loss- and constitutive gain-of-function approaches. We found that during development, the Mek/ERK1/2-MAPK pathway plays a primary role in Schwann cell differentiation, distinct from mTOR. However, during active myelination, ERK1/2 is dependent on mTOR signaling to drive the growth of the myelin sheath and regulate its thickness. Finally, our data suggest that peripheral nerve pathology during adulthood caused by hyperactivation of Mek/ERK1/2-MAPK or PI3K is likely to be independent or dependent on mTOR-signaling in different contexts. Thus, this study highlights the complexities in the roles played by two major intracellular signaling pathways in Schwann cells that affect their differentiation, myelination, and later PNS pathology and predicts that potential therapeutic modulation of these pathways in PNS neuropathies could be a complex process.
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Affiliation(s)
- Akihiro Ishii
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, Connecticut, USA
| | - Miki Furusho
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, Connecticut, USA
| | - Rashmi Bansal
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, Connecticut, USA
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