1
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Chini A, Guha P, Rishi A, Obaid M, Udden SN, Mandal SS. Discovery and functional characterization of LncRNAs associated with inflammation and macrophage activation. Methods 2024; 227:1-16. [PMID: 38703879 DOI: 10.1016/j.ymeth.2024.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 04/24/2024] [Accepted: 05/01/2024] [Indexed: 05/06/2024] Open
Abstract
Long noncoding RNAs (lncRNA) are emerging players in regulation of gene expression and cell signaling and their dysregulation has been implicated in a multitude of human diseases. Recent studies from our laboratory revealed that lncRNAs play critical roles in cytokine regulation, inflammation, and metabolism. We demonstrated that lncRNA HOTAIR, which is a well-known regulator of gene silencing, plays critical roles in modulation of cytokines and proinflammatory genes, and glucose metabolism in macrophages during inflammation. In addition, we recently discovered a series of novel lncRNAs that are closely associated with inflammation and macrophage activation. We termed these as long-noncoding inflammation associated RNAs (LinfRNAs). We are currently engaged in the functional characterization of these hLinfRNAs (human LinfRNAs) with a focus on their roles in inflammation, and we are investigating their potential implications in chronic inflammatory human diseases. Here, we have summarized experimental methods that have been utilized for the discovery and functional characterization of lncRNAs in inflammation and macrophage activation.
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Affiliation(s)
- Avisankar Chini
- Gene Regulation and Epigenetics Research Laboratory, Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX 76019, USA
| | - Prarthana Guha
- Gene Regulation and Epigenetics Research Laboratory, Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX 76019, USA
| | - Ashcharya Rishi
- Gene Regulation and Epigenetics Research Laboratory, Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX 76019, USA
| | - Monira Obaid
- Gene Regulation and Epigenetics Research Laboratory, Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX 76019, USA
| | - Sm Nashir Udden
- Department of Radiation Oncology, The University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Subhrangsu S Mandal
- Gene Regulation and Epigenetics Research Laboratory, Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX 76019, USA.
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2
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Weiß EM, Geldermann M, Martini R, Klein D. Macrophages influence Schwann cell myelin autophagy after nerve injury and in a model of Charcot-Marie-Tooth disease. J Peripher Nerv Syst 2023; 28:341-350. [PMID: 37209383 DOI: 10.1111/jns.12561] [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: 03/07/2023] [Revised: 05/04/2023] [Accepted: 05/15/2023] [Indexed: 05/22/2023]
Abstract
BACKGROUND AND AIMS The complex cellular and molecular interactions between Schwann cells (SCs) and macrophages during Wallerian degeneration are a prerequisite to allow rapid uptake and degradation of myelin debris and axonal regeneration after peripheral nerve injury. In contrast, in non-injured nerves of Charcot-Marie-Tooth 1 neuropathies, aberrant macrophage activation by SCs carrying myelin gene defects is a disease amplifier that drives nerve damage and subsequent functional decline. Consequently, targeting nerve macrophages might be a translatable treatment strategy to mitigate disease outcome in CMT1 patients. Indeed, in previous approaches, macrophage targeting alleviated the axonopathy and promoted sprouting of damaged fibers. Surprisingly, this was still accompanied by robust myelinopathy in a model for CMT1X, suggesting additional cellular mechanisms of myelin degradation in mutant peripheral nerves. We here investigated the possibility of an increased SC-related myelin autophagy upon macrophage targeting in Cx32def mice. METHODS Combining ex vivo and in vivo approaches, macrophages were targeted by PLX5622 treatment. SC autophagy was investigated by immunohistochemical and electron microscopical techniques. RESULTS We demonstrate a robust upregulation of markers for SC autophagy after injury and in genetically-mediated neuropathy when nerve macrophages are pharmacologically depleted. Corroborating these findings, we provide ultrastructural evidence for increased SC myelin autophagy upon treatment in vivo. INTERPRETATION These findings reveal a novel communication and interaction between SCs and macrophages. This identification of alternative pathways of myelin degradation may have important implications for a better understanding of therapeutic mechanisms of pharmacological macrophage targeting in diseased peripheral nerves.
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Affiliation(s)
- Eva Maria Weiß
- Department of Neurology, Developmental Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Miriam Geldermann
- Department of Neurology, Developmental Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Rudolf Martini
- Department of Neurology, Developmental Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Dennis Klein
- Department of Neurology, Developmental Neurobiology, University Hospital Würzburg, Würzburg, Germany
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3
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Kaur S, Zhang X, Patel S, Rodriguez YA, Luther KJ, Alghafli G, Lang RM, Abrams CK, Dobrowsky RT. Pharmacologic Targeting of the C-Terminus of Heat Shock Protein 90 Improves Neuromuscular Function in Animal Models of Charcot Marie Tooth X1 Disease. ACS Pharmacol Transl Sci 2023; 6:306-319. [PMID: 36798471 PMCID: PMC9926526 DOI: 10.1021/acsptsci.2c00223] [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: 11/14/2022] [Indexed: 01/22/2023]
Abstract
Charcot-Marie-Tooth X1 (CMTX1) disease is an inherited peripheral neuropathy that arises from loss-of-function mutations in the protein connexin 32 (Cx32). CMTX1 currently lacks a pharmacologic approach toward disease management, and we have previously shown that modulating the expression of molecular chaperones using novologue therapy may provide a viable disease-modifying approach to treat metabolic and demyelinating neuropathies. Cemdomespib is an orally bioavailable novologue that manifests neuroprotective activity by modulating the expression of heat shock protein 70 (Hsp70). We examined if 1 to 5 months of daily cemdomespib therapy may improve neuropathic symptoms in three mouse models of CMTX1 (Cx32 deficient (Cx32def), T55I-Cx32def, and R75W-Cx32 mice). Daily drug therapy significantly improved motor nerve conduction velocity (MNCV) and grip strength in all three models, but the compound muscle action potential was only improved in Cx32def mice. Drug efficacy required Hsp70 as improvements in MNCV, and the grip strength was abrogated in Cx32def × Hsp70 knockout mice. Five months of novologue therapy was associated with improved neuromuscular junction morphology, femoral motor nerve myelination, reduction in foamy macrophages, and a decrease in Schwann cell c-jun levels. To determine if c-jun may be downstream of Hsp70 and necessary for drug efficacy, c-jun expression was specifically deleted in Schwann cells of Cx32def mice. While the deletion of c-jun worsened the neuropathy, cemdomespib therapy remained effective in improving MNCV and grip strength. Our data show that cemdomespib therapy improves CMTX1-linked neuropathy in an Hsp70-dependent but a c-jun-independent manner and without regard to the nature of the underlying Cx32 mutation.
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Affiliation(s)
- Sukhmanjit Kaur
- Department
of Pharmacology and Toxicology, University
of Kansas, Lawrence, Kansas 66045, United States
| | - Xinyue Zhang
- Department
of Pharmacology and Toxicology, University
of Kansas, Lawrence, Kansas 66045, United States
| | - Sugandha Patel
- Department
of Pharmacology and Toxicology, University
of Kansas, Lawrence, Kansas 66045, United States
| | - Yssa A. Rodriguez
- Department
of Pharmacology and Toxicology, University
of Kansas, Lawrence, Kansas 66045, United States
| | - Kylie J. Luther
- Department
of Pharmacology and Toxicology, University
of Kansas, Lawrence, Kansas 66045, United States
| | - Ghufran Alghafli
- Department
of Pharmacology and Toxicology, University
of Kansas, Lawrence, Kansas 66045, United States
| | - Ryan M. Lang
- Department
of Pharmacology and Toxicology, University
of Kansas, Lawrence, Kansas 66045, United States
| | - Charles K. Abrams
- Department
of Neurology and Rehabilitation and Biomedical Engineering, College
of Medicine, University of Illinois Chicago, Chicago, Illinois 60612, United States
| | - Rick T. Dobrowsky
- Department
of Pharmacology and Toxicology, University
of Kansas, Lawrence, Kansas 66045, United States
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4
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Abrams CK, Lancaster E, Li JJ, Dungan G, Gong D, Scherer SS, Freidin MM. Knock-in mouse models for CMTX1 show a loss of function phenotype in the peripheral nervous system. Exp Neurol 2023; 360:114277. [PMID: 36403785 DOI: 10.1016/j.expneurol.2022.114277] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 10/28/2022] [Accepted: 11/16/2022] [Indexed: 11/20/2022]
Abstract
The X-linked form of Charcot-Marie-Tooth disease (CMTX1) is the second most common form of CMT. In this study we used CRISPR/Cas9 to develop new "knock-in" models of CMTX1 that are more representative of the spectrum of mutations seen with CMTX1 than the Cx32 knockout (KO) mouse model used previously. We compared mice of four genotypes - wild-type, Cx32KO, p.T55I, and p.R75W. Sciatic motor conduction velocity slowing was the most robust electrophysiologic indicator of neuropathy, showing reductions in the Cx32KO by 3 months and in the p.T55I and p.R75W mice by 6 months. At both 6 and 12 months, all three mutant genotypes showed reduced four limb and hind limb grip strength compared to WT mice. Performance on 6 and 12 mm width balance beams revealed deficits that were most pronounced at on the 6 mm balance beam at 6 months of age. There were pathological changes of myelinated axons in the femoral motor nerve in all three mutant lines by 3 months of age, and these became more pronounced at 6 and 12 months of age; sensory nerves (femoral sensory and the caudal nerve of the tail) appeared normal at all ages examined. Our results demonstrate that mice can be used to show the pathogenicity of human GJB1 mutations, and these new models for CMTX1 should facilitate the preclinical work for developing treatments for CMTX1.
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Affiliation(s)
- Charles K Abrams
- Department of Neurology and Rehabilitation, College of Medicine, University of Illinois at Chicago, 912 South Wood Street, Chicago, IL 60657, USA; Richard and Loan Hill Department of Biomedical Engineering, University of Illinois at Chicago, USA.
| | - Eunjoo Lancaster
- Department of Neurology, The Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA..
| | - Jian J Li
- Department of Neurology, The Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA..
| | - Gabriel Dungan
- Department of Neurology and Rehabilitation, College of Medicine, University of Illinois at Chicago, 912 South Wood Street, Chicago, IL 60657, USA
| | - David Gong
- Richard and Loan Hill Department of Biomedical Engineering, University of Illinois at Chicago, USA.
| | - Steven S Scherer
- Department of Neurology, The Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA..
| | - Mona M Freidin
- Department of Neurology and Rehabilitation, College of Medicine, University of Illinois at Chicago, 912 South Wood Street, Chicago, IL 60657, USA.
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5
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Beloribi-Djefaflia S, Attarian S. Treatment of Charcot-Marie-Tooth neuropathies. Rev Neurol (Paris) 2023; 179:35-48. [PMID: 36588067 DOI: 10.1016/j.neurol.2022.11.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 11/18/2022] [Accepted: 11/24/2022] [Indexed: 12/31/2022]
Abstract
Charcot-Marie-Tooth (CMT) is a heterogeneous group of inherited neuropathies that affect the peripheral nerves and slowly cause progressive disability. Currently, there is no effective therapy. Patients' management is based on rehabilitation and occupational therapy, fatigue, and pain treatment with regular follow-up according to the severity of the disease. In the last three decades, much progress has been made to identify mutations involved in the different types of CMT, decipher the pathophysiology of the disease, and identify key genes and pathways that could be targeted to propose new therapeutic strategies. Genetic therapy is one of the fields of interest to silence genes such as PMP22 in CMT1A or to express GJB1 in CMT1X. Among the most promising molecules, inhibitors of the NRG-1 axis and modulators of UPR or the HDACs enzyme family could be used in different types of CMT.
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Affiliation(s)
- S Beloribi-Djefaflia
- Reference center for neuromuscular disorders and ALS, AP-HM, CHU La Timone, Marseille, France
| | - S Attarian
- Reference center for neuromuscular disorders and ALS, AP-HM, CHU La Timone, Marseille, France; FILNEMUS, European Reference Network for Rare Diseases (ERN), Marseille, France; Medical Genetics, Aix Marseille Université-Inserm UMR_1251, 13005 Marseille, France.
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6
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Pisciotta C, Shy ME. Hereditary neuropathy. HANDBOOK OF CLINICAL NEUROLOGY 2023; 195:609-617. [PMID: 37562889 DOI: 10.1016/b978-0-323-98818-6.00009-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/12/2023]
Abstract
The hereditary neuropathies, collectively referred as Charcot-Marie-Tooth disease (CMT) and related disorders, are heterogeneous genetic peripheral nerve disorders that collectively comprise the commonest inherited neurological disease with an estimated prevalence of 1:2500 individuals. The field of hereditary neuropathies has made significant progress in recent years with respect to both gene discovery and treatment as a result of next-generation sequencing (NGS) approach. These investigations which have identified over 100 causative genes and new mutations have made the classification of CMT even more challenging. Despite so many different mutated genes, the majority of CMT forms share a similar clinical phenotype, and due to this phenotypic homogeneity, genetic testing in CMT is increasingly being performed through the use of NGS panels. The majority of patients still have a mutation in one the four most common genes (PMP22 duplication-CMT1A, MPZ-CMT1B, GJB1-CMTX1, and MFN2-CMT2A). This chapter focuses primarily on these four forms and their potential therapeutic approaches.
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Affiliation(s)
- Chiara Pisciotta
- Department of Clinical Neurosciences, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy.
| | - Michael E Shy
- Department of Neurology, University of Iowa Hospitals and Clinics, Iowa City, IA, United States
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7
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Di Girolamo N, Park M. Cell identity changes in ocular surface Epithelia. Prog Retin Eye Res 2022:101148. [DOI: 10.1016/j.preteyeres.2022.101148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/13/2022] [Accepted: 11/09/2022] [Indexed: 11/21/2022]
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8
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Ostertag C, Klein D, Martini R. Presymptomatic macrophage targeting has a long-lasting therapeutic effect on treatment termination. Exp Neurol 2022; 357:114195. [PMID: 35931123 DOI: 10.1016/j.expneurol.2022.114195] [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: 04/29/2022] [Revised: 07/11/2022] [Accepted: 07/31/2022] [Indexed: 11/24/2022]
Abstract
Macrophage-mediated inflammation is a potent driver of disease progression in mouse models of Charcot-Marie-Tooth (CMT) 1 diseases. This leads to the possibility to consider these cells as therapeutic targets to dampen disease outcome in the so far non-treatable neuropathies. As a pharmacological proof-of-principle study, long-term targeting of nerve macrophages with the orally applied CSF-1 receptor specific kinase (c-FMS) inhibitor PLX5622 showed a substantial alleviation of the neuropathy in distinct CMT1 mouse models. However, regarding translational options, clinically relevant questions emerged regarding treatment onset, duration and termination. Corroborating previous data, we here show that in a model for CMT1B, peripheral neuropathy was substantially alleviated after early continuous PLX5622 treatment in CMT1B mice, leading to preserved motor function. However, late-onset treatment failed to mitigate histopathological and clinical features, despite a similar reduction in the number of macrophages. Surprisingly, in CMT1B mice, terminating early PLX5622 treatment at six months was still sufficient to preserve motor function at 12 months of age, suggesting a long-lasting, therapeutic effect of early macrophage depletion. This novel and unexpected finding may have important translational implications, since we here show that continuous macrophage targeting appears not to be necessary for disease alleviation, provided that the treatment starts within an early, critical time window.
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Affiliation(s)
- Charlotte Ostertag
- Department of Neurology, Developmental Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Dennis Klein
- Department of Neurology, Developmental Neurobiology, University Hospital Würzburg, Würzburg, Germany.
| | - Rudolf Martini
- Department of Neurology, Developmental Neurobiology, University Hospital Würzburg, Würzburg, Germany.
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9
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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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10
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Msheik Z, El Massry M, Rovini A, Billet F, Desmoulière A. The macrophage: a key player in the pathophysiology of peripheral neuropathies. J Neuroinflammation 2022; 19:97. [PMID: 35429971 PMCID: PMC9013246 DOI: 10.1186/s12974-022-02454-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 03/29/2022] [Indexed: 12/22/2022] Open
Abstract
Macrophages are present in all mammalian tissues and coexist with various cell types in order to respond to different environmental cues. However, the role of these cells has been underestimated in the context of peripheral nerve damage. More importantly, macrophages display divergent characteristics, associated with their origin, and in response to the modulatory effects of their microenvironment. Interestingly, the advent of new techniques such as fate mapping and single-cell transcriptomics and their synergistic use has helped characterize in detail the origin and fate of tissue-resident macrophages in the peripheral nervous system (PNS). Furthermore, these techniques have allowed a better understanding of their functions from simple homeostatic supervisors to chief regulators in peripheral neuropathies. In this review, we summarize the latest knowledge about macrophage ontogeny, function and tissue identity, with a particular focus on PNS-associated cells, as well as their interaction with reactive oxygen species under physiological and pathological conditions. We then revisit the process of Wallerian degeneration, describing the events accompanying axon degeneration, Schwann cell activation and most importantly, macrophage recruitment to the site of injury. Finally, we review these processes in light of internal and external insults to peripheral nerves leading to peripheral neuropathies, the involvement of macrophages and the potential benefit of the targeting of specific macrophages for the alleviation of functional defects in the PNS.
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11
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Connexin Mutations and Hereditary Diseases. Int J Mol Sci 2022; 23:ijms23084255. [PMID: 35457072 PMCID: PMC9027513 DOI: 10.3390/ijms23084255] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 04/04/2022] [Accepted: 04/09/2022] [Indexed: 02/01/2023] Open
Abstract
Inherited diseases caused by connexin mutations are found in multiple organs and include hereditary deafness, congenital cataract, congenital heart diseases, hereditary skin diseases, and X-linked Charcot–Marie–Tooth disease (CMT1X). A large number of knockout and knock-in animal models have been used to study the pathology and pathogenesis of diseases of different organs. Because the structures of different connexins are highly homologous and the functions of gap junctions formed by these connexins are similar, connexin-related hereditary diseases may share the same pathogenic mechanism. Here, we analyze the similarities and differences of the pathology and pathogenesis in animal models and find that connexin mutations in gap junction genes expressed in the ear, eye, heart, skin, and peripheral nerves can affect cellular proliferation and differentiation of corresponding organs. Additionally, some dominant mutations (e.g., Cx43 p.Gly60Ser, Cx32 p.Arg75Trp, Cx32 p.Asn175Asp, and Cx32 p.Arg142Trp) are identified as gain-of-function variants in vivo, which may play a vital role in the onset of dominant inherited diseases. Specifically, patients with these dominant mutations receive no benefits from gene therapy. Finally, the complete loss of gap junctional function or altered channel function including permeability (ions, adenosine triphosphate (ATP), Inositol 1,4,5-trisphosphate (IP3), Ca2+, glucose, miRNA) and electric activity are also identified in vivo or in vitro.
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12
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Klein D, Groh J, Yuan X, Berve K, Stassart R, Fledrich R, Martini R. Early targeting of endoneurial macrophages alleviates the neuropathy and affects abnormal Schwann cell differentiation in a mouse model of Charcot-Marie-Tooth 1A. Glia 2022; 70:1100-1116. [PMID: 35188681 DOI: 10.1002/glia.24158] [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: 12/10/2021] [Revised: 01/26/2022] [Accepted: 01/31/2022] [Indexed: 12/11/2022]
Abstract
We have previously shown that targeting endoneurial macrophages with the orally applied CSF-1 receptor specific kinase (c-FMS) inhibitor PLX5622 from the age of 3 months onwards led to a substantial alleviation of the neuropathy in mouse models of Charcot-Marie-Tooth (CMT) 1X and 1B disease, which are genetically-mediated nerve disorders not treatable in humans. The same approach failed in a model of CMT1A (PMP22-overexpressing mice, line C61), representing the most frequent form of CMT. This was unexpected since previous studies identified macrophages contributing to disease severity in the same CMT1A model. Here we re-approached the possibility of alleviating the neuropathy in a model of CMT1A by targeting macrophages at earlier time points. As a proof-of-principle experiment, we genetically inactivated colony-stimulating factor-1 (CSF-1) in CMT1A mice, which resulted in lower endoneurial macrophage numbers and alleviated the neuropathy. Based on these observations, we pharmacologically ablated macrophages in newborn CMT1A mice by feeding their lactating mothers with chow containing PLX5622, followed by treatment of the respective progenies after weaning until the age of 6 months. We found that peripheral neuropathy was substantially alleviated after early postnatal treatment, leading to preserved motor function in CMT1A mice. Moreover, macrophage depletion affected the altered Schwann cell differentiation phenotype. These findings underscore the targetable role of macrophage-mediated inflammation in peripheral nerves of inherited neuropathies, but also emphasize the need for an early treatment start confined to a narrow therapeutic time window in CMT1A models and potentially in respective patients.
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Affiliation(s)
- Dennis Klein
- Department of Neurology, Developmental Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Janos Groh
- Department of Neurology, Developmental Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Xidi Yuan
- Department of Neurology, Developmental Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Kristina Berve
- Department of Neurology, Developmental Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Ruth Stassart
- Paul-Flechsig-Institute of Neuropathology, University Clinic Leipzig, Leipzig, Germany
| | - Robert Fledrich
- Institute of Anatomy, University of Leipzig, Leipzig, Germany
| | - Rudolf Martini
- Department of Neurology, Developmental Neurobiology, University Hospital Würzburg, Würzburg, Germany
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13
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Tallon C, Sharma A, Zhang Z, Thomas AG, Ng J, Zhu X, Donoghue A, Schulte M, Joe TR, Kambhampati SP, Sharma R, Liaw K, Kannan S, Kannan RM, Slusher BS. Dendrimer-2PMPA Delays Muscle Function Loss and Denervation in a Murine Model of Amyotrophic Lateral Sclerosis. Neurotherapeutics 2022; 19:274-288. [PMID: 34984651 PMCID: PMC9130402 DOI: 10.1007/s13311-021-01159-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/05/2021] [Indexed: 01/03/2023] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease where muscle weakness and neuromuscular junction (NMJ) denervation precede motor neuron cell death. Although acetylcholine is the canonical neurotransmitter at the mammalian NMJ synapse, glutamate has recently been identified as a critical neurotransmitter for NMJ development and maintenance. One source of glutamate is through the catabolism of N-acetyl-aspartyl-glutamate (NAAG), which is found in mM concentrations in mammalian motoneurons, where it is released upon stimulation and hydrolyzed to glutamate by the glial enzyme glutamate carboxypeptidase II (GCPII). Using the SOD1G93A model of ALS, we found an almost fourfold elevation of GCPII enzymatic activity in SOD1G93A versus WT muscle and a robust increase in GCPII expression which was specifically associated with activated macrophages infiltrating the muscle. 2-(Phosphonomethyl)pentanedioic acid (2PMPA) is a potent GCPII inhibitor which robustly blocks glutamate release from NAAG but is highly polar with limited tissue penetration. To improve this, we covalently attached 2PMPA to a hydroxyl polyamidoamine (PAMAM-G4-OH) dendrimer delivery system (D-2PMPA) which is known to target activated macrophages in affected tissues. Systemic D-2PMPA therapy (20 mg/kg 2PMPA equivalent; IP 2 × /week) was found to localize in muscle macrophages in SOD1G93A mice and completely normalize the enhanced GCPII activity. Although no changes in body weight or survival were observed, D-2PMPA significantly improved grip strength and inhibited the loss of NMJ innervation in the gastrocnemius muscles. Our finding that inhibiting elevated GCPII activity in SOD1G93A muscle can prolong muscle function and delay NMJ denervation may have early therapeutic implications for ALS patients.
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Affiliation(s)
- Carolyn Tallon
- Johns Hopkins Drug Discovery, Johns Hopkins University School of Medicine, Baltimore, USA
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Anjali Sharma
- Center for Nanomedicine-Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Zhi Zhang
- Center for Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, USA
- Department of Natural Sciences, University of Michigan-Dearborn, Dearborn, MI, 48128, USA
| | - Ajit G Thomas
- Johns Hopkins Drug Discovery, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Justin Ng
- Johns Hopkins Drug Discovery, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Xiaolei Zhu
- Johns Hopkins Drug Discovery, Johns Hopkins University School of Medicine, Baltimore, USA
- Department of Psychiatry and Behavioral Science, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Amanda Donoghue
- Johns Hopkins Drug Discovery, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Michael Schulte
- Johns Hopkins Drug Discovery, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Tawnjerae R Joe
- Johns Hopkins Drug Discovery, Johns Hopkins University School of Medicine, Baltimore, USA
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Siva P Kambhampati
- Center for Nanomedicine-Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Rishi Sharma
- Center for Nanomedicine-Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Kevin Liaw
- Center for Nanomedicine-Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Sujatha Kannan
- Center for Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, USA
- Hugo W. Moser Research Institute at Kennedy-Krieger, Inc, Baltimore, USA
| | - Rangaramanujam M Kannan
- Center for Nanomedicine-Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, USA
- Hugo W. Moser Research Institute at Kennedy-Krieger, Inc, Baltimore, USA
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Barbara S Slusher
- Johns Hopkins Drug Discovery, Johns Hopkins University School of Medicine, Baltimore, USA.
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, USA.
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, USA.
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, USA.
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, USA.
- Department of Psychiatry and Behavioral Science, Johns Hopkins University School of Medicine, Baltimore, USA.
- Johns Hopkins University School of Medicine, 855 N. Wolfe Street, Rangos 278, Baltimore, MD, 21205, USA.
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14
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Chitu V, Biundo F, Stanley ER. Colony stimulating factors in the nervous system. Semin Immunol 2021; 54:101511. [PMID: 34743926 DOI: 10.1016/j.smim.2021.101511] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 10/23/2021] [Indexed: 01/02/2023]
Abstract
Although traditionally seen as regulators of hematopoiesis, colony-stimulating factors (CSFs) have emerged as important players in the nervous system, both in health and disease. This review summarizes the cellular sources, patterns of expression and physiological roles of the macrophage (CSF-1, IL-34), granulocyte-macrophage (GM-CSF) and granulocyte (G-CSF) colony stimulating factors within the nervous system, with a particular focus on their actions on microglia. CSF-1 and IL-34, via the CSF-1R, are required for the development, proliferation and maintenance of essentially all CNS microglia in a temporal and regional specific manner. In contrast, in steady state, GM-CSF and G-CSF are mainly involved in regulation of microglial function. The alterations in expression of these growth factors and their receptors, that have been reported in several neurological diseases, are described and the outcomes of their therapeutic targeting in mouse models and humans are discussed.
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Affiliation(s)
- Violeta Chitu
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
| | - Fabrizio Biundo
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
| | - E Richard Stanley
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
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15
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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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16
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Stavrou M, Sargiannidou I, Georgiou E, Kagiava A, Kleopa KA. Emerging Therapies for Charcot-Marie-Tooth Inherited Neuropathies. Int J Mol Sci 2021; 22:6048. [PMID: 34205075 PMCID: PMC8199910 DOI: 10.3390/ijms22116048] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/29/2021] [Accepted: 05/31/2021] [Indexed: 12/12/2022] Open
Abstract
Inherited neuropathies known as Charcot-Marie-Tooth (CMT) disease are genetically heterogeneous disorders affecting the peripheral nerves, causing significant and slowly progressive disability over the lifespan. The discovery of their diverse molecular genetic mechanisms over the past three decades has provided the basis for developing a wide range of therapeutics, leading to an exciting era of finding treatments for this, until now, incurable group of diseases. Many treatment approaches, including gene silencing and gene replacement therapies, as well as small molecule treatments are currently in preclinical testing while several have also reached clinical trial stage. Some of the treatment approaches are disease-specific targeted to the unique disease mechanism of each CMT form, while other therapeutics target common pathways shared by several or all CMT types. As promising treatments reach the stage of clinical translation, optimal outcome measures, novel biomarkers and appropriate trial designs are crucial in order to facilitate successful testing and validation of novel treatments for CMT patients.
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Affiliation(s)
- Marina Stavrou
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus; (M.S.); (I.S.); (E.G.); (A.K.)
| | - Irene Sargiannidou
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus; (M.S.); (I.S.); (E.G.); (A.K.)
| | - Elena Georgiou
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus; (M.S.); (I.S.); (E.G.); (A.K.)
| | - Alexia Kagiava
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus; (M.S.); (I.S.); (E.G.); (A.K.)
| | - Kleopas A. Kleopa
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus; (M.S.); (I.S.); (E.G.); (A.K.)
- Center for Neuromuscular Diseases, The Cyprus Institute of Neurology and Genetics, Cyprus School of Molecular Medicine, Nicosia 2371, Cyprus
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17
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Peinado A, Asche-Godin SL, Freidin MM, Abrams CK. Effects of early crush on aging wild type and Connexin 32 knockout mice: Evidence for a neuroprotective state in CMT1X mouse nerve. J Peripher Nerv Syst 2021; 26:167-176. [PMID: 33624350 DOI: 10.1111/jns.12436] [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: 12/03/2019] [Revised: 01/19/2021] [Accepted: 02/18/2021] [Indexed: 11/29/2022]
Abstract
The long-term sequelae of nerve injury as well as age-related neurodegeneration have been documented in numerous studies, however the role of Cx32 in these processes is not well understood. There is a need for better understanding of the molecular mechanisms that underlie long-term suboptimal nerve function and for approaches to prevent or improve it. In this communication we describe our studies using whole animal electrophysiology to examine the long-term sequelae of sciatic nerve crush in both WT and Cx32KO mice, a model of X-linked Charcot Marie Tooth disease, a subtype of inherited peripheral neuropathies. We present results from electrical nerve recordings done 14 to 27 days and 18 to 20 months after a unilateral sciatic nerve crush performed on 35 to 37-day old mice. Contrary to expectations, we find that whereas crush injury leads to a degradation of WT nerve function relative to uninjured nerves at 18 to 20 months, previously crushed Cx32KO nerves perform at the same level as their uninjured counterparts. Thus, 18 to 20 months after injury, WT nerves perform below the level of normal (uninjured) WT nerves in both motor and sensory nerve function. In contrast, measures of nerve function in Cx32KO mice are degraded for sensory axons but exhibit no additional dysfunction in motor axons. Early nerve injury has no negative electrophysiologic effect on the Cx32 KO motor nerves. Based on our prior demonstration that the transcriptomic profile of uninjured Cx32KO and injured WT sciatic nerves are very similar, the lack of an additional effect of crush on Cx32KO motor nerve parameters suggests that Cx32 knockout may implement a form of neuroprotection that limits the effects of subsequent injury.
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Affiliation(s)
- Alejandro Peinado
- Department of Neurology and Rehabilitation, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Samantha L Asche-Godin
- National Center for the Medical Consequences of Spinal Cord Injury, James J. Peters VA Medical Center, Bronx, NY and The Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Mona M Freidin
- Department of Neurology and Rehabilitation, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Charles K Abrams
- Department of Neurology and Rehabilitation, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
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18
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Freuchet A, Salama A, Remy S, Guillonneau C, Anegon I. IL-34 and CSF-1, deciphering similarities and differences at steady state and in diseases. J Leukoc Biol 2021; 110:771-796. [PMID: 33600012 DOI: 10.1002/jlb.3ru1120-773r] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 01/04/2021] [Accepted: 01/04/2021] [Indexed: 12/11/2022] Open
Abstract
Although IL-34 and CSF-1 share actions as key mediators of monocytes/macrophages survival and differentiation, they also display differences that should be identified to better define their respective roles in health and diseases. IL-34 displays low sequence homology with CSF-1 but has a similar general structure and they both bind to a common receptor CSF-1R, although binding and subsequent intracellular signaling shows differences. CSF-1R expression has been until now mainly described at a steady state in monocytes/macrophages and myeloid dendritic cells, as well as in some cancers. IL-34 has also 2 other receptors, protein-tyrosine phosphatase zeta (PTPζ) and CD138 (Syndecan-1), expressed in some epithelium, cells of the central nervous system (CNS), as well as in numerous cancers. While most, if not all, of CSF-1 actions are mediated through monocyte/macrophages, IL-34 has also other potential actions through PTPζ and CD138. Additionally, IL-34 and CSF-1 are produced by different cells in different tissues. This review describes and discusses similarities and differences between IL-34 and CSF-1 at steady state and in pathological situations and identifies possible ways to target IL-34, CSF-1, and its receptors.
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Affiliation(s)
- Antoine Freuchet
- Centre de Recherche en Transplantation et Immunologie UMR1064, INSERM, Université de Nantes, Nantes, France.,Institut de Transplantation Urologie Néphrologie (ITUN), CHU Nantes, Nantes, France.,LabEx IGO "Immunotherapy, Graft, Oncology", Nantes, France
| | - Apolline Salama
- Centre de Recherche en Transplantation et Immunologie UMR1064, INSERM, Université de Nantes, Nantes, France.,Institut de Transplantation Urologie Néphrologie (ITUN), CHU Nantes, Nantes, France.,LabEx IGO "Immunotherapy, Graft, Oncology", Nantes, France
| | - Séverine Remy
- Centre de Recherche en Transplantation et Immunologie UMR1064, INSERM, Université de Nantes, Nantes, France.,Institut de Transplantation Urologie Néphrologie (ITUN), CHU Nantes, Nantes, France.,LabEx IGO "Immunotherapy, Graft, Oncology", Nantes, France
| | - Carole Guillonneau
- Centre de Recherche en Transplantation et Immunologie UMR1064, INSERM, Université de Nantes, Nantes, France.,Institut de Transplantation Urologie Néphrologie (ITUN), CHU Nantes, Nantes, France.,LabEx IGO "Immunotherapy, Graft, Oncology", Nantes, France
| | - Ignacio Anegon
- Centre de Recherche en Transplantation et Immunologie UMR1064, INSERM, Université de Nantes, Nantes, France.,Institut de Transplantation Urologie Néphrologie (ITUN), CHU Nantes, Nantes, France.,LabEx IGO "Immunotherapy, Graft, Oncology", Nantes, France
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19
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Huang Z, Powell R, Phillips JB, Haastert-Talini K. Perspective on Schwann Cells Derived from Induced Pluripotent Stem Cells in Peripheral Nerve Tissue Engineering. Cells 2020; 9:E2497. [PMID: 33213068 PMCID: PMC7698557 DOI: 10.3390/cells9112497] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 11/13/2020] [Accepted: 11/16/2020] [Indexed: 02/06/2023] Open
Abstract
Schwann cells play a crucial role in successful peripheral nerve repair and regeneration by supporting both axonal growth and myelination. Schwann cells are therefore a feasible option for cell therapy treatment of peripheral nerve injury. However, sourcing human Schwann cells at quantities required for development beyond research is challenging. Due to their availability, rapid in vitro expansion, survival, and integration within the host tissue, stem cells have attracted considerable attention as candidate cell therapies. Among them, induced pluripotent stem cells (iPSCs) with the associated prospects for personalized treatment are a promising therapy to take the leap from bench to bedside. In this critical review, we firstly focus on the current knowledge of the Schwann cell phenotype in regard to peripheral nerve injury, including crosstalk with the immune system during peripheral nerve regeneration. Then, we review iPSC to Schwann cell derivation protocols and the results from recent in vitro and in vivo studies. We finally conclude with some prospects for the use of iPSCs in clinical settings.
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Affiliation(s)
- Zhong Huang
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, 30623 Hannover, Germany;
- Center for Systems Neuroscience (ZSN) Hannover, 30559 Hannover, Germany
| | - Rebecca Powell
- Department of Pharmacology, UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AX, UK;
- UCL Centre for Nerve Engineering, University College London, London WC1E 6BT, UK
| | - James B. Phillips
- Department of Pharmacology, UCL School of Pharmacy, 29-39 Brunswick Square, London WC1N 1AX, UK;
- UCL Centre for Nerve Engineering, University College London, London WC1E 6BT, UK
| | - Kirsten Haastert-Talini
- Institute of Neuroanatomy and Cell Biology, Hannover Medical School, 30623 Hannover, Germany;
- Center for Systems Neuroscience (ZSN) Hannover, 30559 Hannover, Germany
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20
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Yao Y, Wang C. Dedifferentiation: inspiration for devising engineering strategies for regenerative medicine. NPJ Regen Med 2020; 5:14. [PMID: 32821434 PMCID: PMC7395755 DOI: 10.1038/s41536-020-00099-8] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 07/08/2020] [Indexed: 02/07/2023] Open
Abstract
Cell dedifferentiation is the process by which cells grow reversely from a partially or terminally differentiated stage to a less differentiated stage within their own lineage. This extraordinary phenomenon, observed in many physiological processes, inspires the possibility of developing new therapeutic approaches to regenerate damaged tissue and organs. Meanwhile, studies also indicate that dedifferentiation can cause pathological changes. In this review, we compile the literature describing recent advances in research on dedifferentiation, with an emphasis on tissue-specific findings, cellular mechanisms, and potential therapeutic applications from an engineering perspective. A critical understanding of such knowledge may provide fresh insights for designing new therapeutic strategies for regenerative medicine based on the principle of cell dedifferentiation.
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Affiliation(s)
- Yongchang Yao
- Department of Joint Surgery, The First Affiliated Hospital of Guangzhou Medical University, 510120 Guangzhou, China.,Guangdong Key Laboratory of Orthopaedic Technology and Implant Materials, Guangzhou, China
| | - Chunming Wang
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau SAR, China
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21
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Trias E, Kovacs M, King PH, Si Y, Kwon Y, Varela V, Ibarburu S, Moura IC, Hermine O, Beckman JS, Barbeito L. Schwann cells orchestrate peripheral nerve inflammation through the expression of CSF1, IL-34, and SCF in amyotrophic lateral sclerosis. Glia 2019; 68:1165-1181. [PMID: 31859421 DOI: 10.1002/glia.23768] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 12/03/2019] [Accepted: 12/10/2019] [Indexed: 12/12/2022]
Abstract
Distal axonopathy is a recognized pathological feature of amyotrophic lateral sclerosis (ALS). In the peripheral nerves of ALS patients, motor axon loss elicits a Wallerian-like degeneration characterized by denervated Schwann cells (SCs) together with immune cell infiltration. However, the pathogenic significance of denervated SCs accumulating following impaired axonal growth in ALS remains unclear. Here, we analyze SC phenotypes in sciatic nerves of ALS patients and paralytic SOD1G93A rats, and identify remarkably similar and specific reactive SC phenotypes based on the pattern of S100β, GFAP, isolectin and/or p75NTR immunoreactivity. Different subsets of reactive SCs expressed colony-stimulating factor-1 (CSF1) and Interleukin-34 (IL-34) and closely interacted with numerous endoneurial CSF-1R-expressing monocyte/macrophages, suggesting a paracrine mechanism of myeloid cell expansion and activation. SCs bearing phagocytic phenotypes as well as endoneurial macrophages expressed stem cell factor (SCF), a trophic factor that attracts and activates mast cells through the c-Kit receptor. Notably, a subpopulation of Ki67+ SCs expressed c-Kit in the sciatic nerves of SOD1G93A rats, suggesting a signaling pathway that fuels SC proliferation in ALS. c-Kit+ mast cells were also abundant in the sciatic nerve from ALS donors but not in controls. Pharmacological inhibition of CSF-1R and c-Kit with masitinib in SOD1G93A rats potently reduced SC reactivity and immune cell infiltration in the sciatic nerve and ventral roots, suggesting a mechanism by which the drug ameliorates peripheral nerve pathology. These findings provide strong evidence for a previously unknown inflammatory mechanism triggered by SCs in ALS peripheral nerves that has broad application in developing novel therapies.
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Affiliation(s)
| | | | - Peter H King
- Department of Neurology, University of Alabama, Birmingham, Alabama.,Birmingham Veterans Affairs Medical Center, Birmingham, Alabama
| | - Ying Si
- Department of Neurology, University of Alabama, Birmingham, Alabama.,Birmingham Veterans Affairs Medical Center, Birmingham, Alabama
| | - Yuri Kwon
- Department of Neurology, University of Alabama, Birmingham, Alabama
| | | | | | - Ivan C Moura
- Imagine Institute, Hôpital Necker, Paris, France.,INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic Implications, Paris, France.,Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Paris, France.,CNRS ERL 8254, Paris, France.,Laboratory of Excellence GR-Ex, Paris, France.,Equipe Labélisée par la Ligue Nationale contre le cancer, Paris, France
| | - Olivier Hermine
- Imagine Institute, Hôpital Necker, Paris, France.,INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic Implications, Paris, France.,Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, Paris, France.,CNRS ERL 8254, Paris, France.,Laboratory of Excellence GR-Ex, Paris, France.,Equipe Labélisée par la Ligue Nationale contre le cancer, Paris, France.,AB Science, Paris, France.,Department of Hematology, Necker Hospital, Paris, France.,Centre national de référence des mastocytoses (CEREMAST), Paris, France
| | - Joseph S Beckman
- Linus Pauling Institute, Department of Biochemistry and Biophysics, Environmental Health Sciences Center, Oregon State University, Corvallis, Oregon
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22
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Fernandez-Lizarbe S, Civera-Tregón A, Cantarero L, Herrer I, Juarez P, Hoenicka J, Palau F. Neuroinflammation in the pathogenesis of axonal Charcot-Marie-Tooth disease caused by lack of GDAP1. Exp Neurol 2019; 320:113004. [PMID: 31271761 DOI: 10.1016/j.expneurol.2019.113004] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Revised: 06/17/2019] [Accepted: 06/28/2019] [Indexed: 01/17/2023]
Abstract
Mutations in the GDAP1 mitochondrial outer membrane gene cause Charcot-Marie-Tooth (CMT) neuropathy. Reduction or absence of GDAP1 has been associated with abnormal changes in the mitochondrial morphology and dynamics, oxidative stress and changes in calcium homeostasis. Neuroinflammation has been described in rodent models of genetic demyelinating CMT neuropathies but not in CMT primarily associated with axonopathy. Inflammatory processes have also been related to mitochondrial changes and oxidative stress in central neurodegenerative disorders. Here we investigated the presence of neuroinflammation in the axonal neuropathy of the Gdap1-/- mice. We showed by transcriptome profile of spinal cord and the in vivo detection of activated phagocytes that the absence of GDAP1 is associated with upregulation of inflammatory pathways. We observed reactive gliosis in spinal cord with increase of the astroglia markers GFAP and S100B, and the microglia marker IBA1. Additionally, we found significant increase of inflammatory mediators such as TNF-α and pERK, and C1qa and C1qb proteins of the complement system. Importantly, we observed an increased expression of CD206 and CD86 as M2 and M1 microglia and macrophage response markers, respectively, in Gdap1-/- mice. These inflammatory changes were also associated with abnormal molecular changes in synapses. In summary, we demonstrate that inflammation in spinal cord and sciatic nerve, but not in brain and cerebellum, is part of the pathophysiology of axonal GDAP1-related CMT.
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Affiliation(s)
| | - Azahara Civera-Tregón
- Laboratory of Neurogenetics and Molecular Medicine - IPER, Institut de Recerca Sant Joan de Déu, Barcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Barcelona, Spain
| | - Lara Cantarero
- Laboratory of Neurogenetics and Molecular Medicine - IPER, Institut de Recerca Sant Joan de Déu, Barcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Barcelona, Spain
| | - Isabel Herrer
- Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Paula Juarez
- Centro de Investigación Príncipe Felipe, Valencia, Spain
| | - Janet Hoenicka
- Laboratory of Neurogenetics and Molecular Medicine - IPER, Institut de Recerca Sant Joan de Déu, Barcelona, Spain; Centro de Investigación Biomédica en Red de Salud Mental (CIBESAM), Barcelona, Spain
| | - Francesc Palau
- Laboratory of Neurogenetics and Molecular Medicine - IPER, Institut de Recerca Sant Joan de Déu, Barcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Barcelona, Spain; Department of Genetic and Molecular Medicine - IPER, Hospital Sant Joan de Déu, Barcelona, Spain; Clinic Institute of Medicine and Dermatology (ICMiD), Hospital Clínic, Barcelona, Spain; Division of Pediatrics, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain.
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23
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Lv W, Deng B, Duan W, Li Y, Song X, Ji Y, Li Z, Liu Y, Wang X, Li C. FGF9 alters the Wallerian degeneration process by inhibiting Schwann cell transformation and accelerating macrophage infiltration. Brain Res Bull 2019; 152:285-296. [PMID: 31220553 DOI: 10.1016/j.brainresbull.2019.06.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 06/04/2019] [Accepted: 06/13/2019] [Indexed: 01/06/2023]
Abstract
In vitro experiments have proved that Fibroblast Growth Factor 9 (FGF9) was decreased in Schwann cells (SCs) in which Wallerian degeneration (WD) occurred after nerve injury. We hypothesize that FGF9 downregulation in WD has some biological influence on Schwann cells (SCs) and macrophages - the two most important cell components involved in WD. In this study, we employed strategies to regulate FGF9 in sciatic nerve crush by generating a mouse model, wherein Fgf9 was specifically knocked-out in SCs, and an intraneural injection of human FGF9 protein administered to overexpress FGF9 independently. Furthermore, an inhibitor of extracellular-regulated kinases 1/2 (ERK1/2), PD0325901, was used to clarify the underlying downstream mechanism of ERK1/2 activated by FGF9. Analysis of WD revealed the novel features of FGF9: (i) FGF9 was widely expressed in axons and SCs, and was decreased during WD process. (ii) Fgf9 knockout in SCs impaired the debris clearance and eventually impeded the regeneration of nerve fibers after damage. (iii) Fgf9 knockout in SCs promoted the dedifferentiation of SCs and delayed the infiltration of macrophages by decreasing Mcp1, Tnfα, Il1β levels and leaky blood-nerve-barrier (BNB) in WD. (iv) FGF9 injection preserved the nerve fibers, inhibited SCs dedifferentiation and accelerated macrophages infiltration. (v) ERK1/2 phosphorylation was increased by exogenous FGF9 injection. P75, Cyclin D1, Mcp1, Tnfα, Il1β, c-Jun changes by FGF9 intraneural injection were partially reversed by the ERK1/2 inhibitor. Conclusion was that FGF9 inhibited the dedifferentiation of SCs and accelerated the accumulation of macrophages in WD, and exogenous FGF9 took effects partially by ERK1/2.
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Affiliation(s)
- Wenjing Lv
- Department of Geriatirics, The Affiliated Hospital of Qingdao University, Qingdao 266000, Shandong, PR China.
| | - Binbin Deng
- Department of Neurology, First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang, PR China
| | - Weisong Duan
- Department of Neurology, Second Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei, PR China; Institute of Cardiocerebrovascular Disease, West Heping Road 215, Shijiazhuang 050000, Hebei, PR China; Neurological Laboratory of Hebei Province, Shijiazhuang 050000, Hebei, PR China
| | - Yi Li
- Department of Neurology, Second Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei, PR China; Institute of Cardiocerebrovascular Disease, West Heping Road 215, Shijiazhuang 050000, Hebei, PR China
| | - Xueqin Song
- Department of Neurology, Second Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei, PR China; Institute of Cardiocerebrovascular Disease, West Heping Road 215, Shijiazhuang 050000, Hebei, PR China; Neurological Laboratory of Hebei Province, Shijiazhuang 050000, Hebei, PR China
| | - Yingxiao Ji
- Department of Neurology, People's hospital of Hebei Province, Shijiazhuang 050000, Hebei, PR China
| | - Zhongyao Li
- Department of Neurology, Second Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei, PR China; Neurological Laboratory of Hebei Province, Shijiazhuang 050000, Hebei, PR China
| | - Yakun Liu
- Department of Neurology, Second Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei, PR China; Neurological Laboratory of Hebei Province, Shijiazhuang 050000, Hebei, PR China
| | - Xiaoxiao Wang
- Department of Neurology, First Hospital of Handan City, Handan 056000, Hebei, PR China
| | - Chunyan Li
- Department of Neurology, Second Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei, PR China; Institute of Cardiocerebrovascular Disease, West Heping Road 215, Shijiazhuang 050000, Hebei, PR China; Neurological Laboratory of Hebei Province, Shijiazhuang 050000, Hebei, PR China.
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24
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Zhang W, Xu L, Luo T, Zhao B, Wu F, Li X. Immune-related gene expression profiles of hypothermia adipocytes: Implications for Bell's palsy. Oral Dis 2019; 25:1652-1663. [PMID: 31127963 DOI: 10.1111/odi.13126] [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: 01/15/2019] [Revised: 05/03/2019] [Accepted: 05/14/2019] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To identify immune-related gene expression profiles of adipocytes under low temperatures with RNA sequencing as a model for Bell's palsy implications. METHODS Adipocytes were harvested from the white adipose tissue of male Sprague-Dawley rats and cultured under different acute-grade cold exposure conditions of 30, 20, and 10°C, and their genomes were sequenced for RNA sequencing analysis. The differentially expressed genes (DEGs) were validated with reverse transcription polymerase chain reaction. RESULTS In total, 55 (35 upregulated and 20 downregulated), 121 (76 upregulated and 45 downregulated), and 92 (64 upregulated and 28 downregulated) DEGs were identified under 30, 20, and 10°C compared with the control, respectively. KEGG and GO analysis revealed that the DEGs were considerably enriched in immune-related pathways (leukocyte transendothelial migration and platelet activation) and infection (bacterial invasion of epithelial cells and Salmonella infection). The levels of key inflammatory chemokines (CSF1, CXCL1, CCL2, and CCL7) were enhanced after cold exposure. CONCLUSION These findings broaden our understanding of the immune responses to cold exposure in adipocytes. The molecular profiles of adipocyte immune function will help clarify the potential mechanism impacting myelin, which might contribute to the development of strategies to control Bell's palsy.
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Affiliation(s)
- Wenjuan Zhang
- School and Hospital of Stomatology, Shanxi Medical University, Taiyuan, China
| | - Lei Xu
- School and Hospital of Stomatology, Shanxi Medical University, Taiyuan, China
| | - Tingting Luo
- School and Hospital of Stomatology, Shanxi Medical University, Taiyuan, China.,The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory for Oral Biomedical Engineering of Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Bin Zhao
- School and Hospital of Stomatology, Shanxi Medical University, Taiyuan, China
| | - Feng Wu
- School and Hospital of Stomatology, Shanxi Medical University, Taiyuan, China
| | - Xianqi Li
- School and Hospital of Stomatology, Shanxi Medical University, Taiyuan, China.,Department of Oral and Maxillofacial Surgery, Matsumoto Dental University, Shiojiri, Japan
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25
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Myelinating Glia-Specific Deletion of Fbxo7 in Mice Triggers Axonal Degeneration in the Central Nervous System Together with Peripheral Neuropathy. J Neurosci 2019; 39:5606-5626. [PMID: 31085610 DOI: 10.1523/jneurosci.3094-18.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 04/10/2019] [Accepted: 04/24/2019] [Indexed: 12/25/2022] Open
Abstract
Myelination of axons facilitates the rapid propagation of electrical signals and the long-term integrity of axons. The ubiquitin-proteasome system is essential for proper protein homeostasis, which is particularly crucial for interactions of postmitotic cells. In our study, we examined how the E3 ubiquitin ligase FBXO7-SCF (SKP1, Cul1, F-box protein) expressed in myelinating cells affects the axon-myelin unit. Deletion of Fbxo7 in oligodendrocytes and Schwann cells in mice using the Cnp1-Cre driver line led to motor impairment due to hindlimb paresis. It did not result in apoptosis of myelinating cells, nor did it affect the proper myelination of axons or lead to demyelination. It however triggered axonal degeneration in the CNS and resulted in the severe degeneration of axons in the PNS, inducing a full-blown neuropathy. Both the CNS and PNS displayed inflammation, while the PNS was also characterized by fibrosis, massive infiltration of macrophages, and edema. Tamoxifen-induced deletion of Fbxo7, after myelination using the Plp1-CreERT2 line, led to a small number of degenerated axons and hence a very mild peripheral neuropathy. Interestingly, loss of Fbxo7 also resulted in reduced proteasome activity in Schwann cells but not in cerebellar granule neurons, indicating a specific sensitivity of the former cell type. Together, our results demonstrate an essential role for FBXO7 in myelinating cells to support associated axons, which is fundamental to the proper developmental establishment and the long-term integrity of the axon-myelin unit.SIGNIFICANCE STATEMENT The myelination of axons facilitates the fast propagation of electrical signals and the trophic support of the myelin-axon unit. Here, we report that deletion of Fbxo7 in myelinating cells in mice triggered motor impairment but had no effect on myelin biogenesis. Loss of Fbxo7 in myelinating glia, however, led to axonal degeneration in the CNS and peripheral neuropathy of the axonal type. In addition, we found that Schwann cells were particularly sensitive to Fbxo7 deficiency reflected by reduced proteasome activity. Based on these findings, we conclude that Fbxo7 is essential for the support of the axon-myelin unit and long-term axonal health.
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26
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Belin S, Ornaghi F, Shackleford G, Wang J, Scapin C, Lopez-Anido C, Silvestri N, Robertson N, Williamson C, Ishii A, Taveggia C, Svaren J, Bansal R, Schwab MH, Nave K, Fratta P, D’Antonio M, Poitelon Y, Feltri ML, Wrabetz L. Neuregulin 1 type III improves peripheral nerve myelination in a mouse model of congenital hypomyelinating neuropathy. Hum Mol Genet 2019; 28:1260-1273. [PMID: 30535360 PMCID: PMC6452193 DOI: 10.1093/hmg/ddy420] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 11/06/2018] [Accepted: 12/02/2018] [Indexed: 12/13/2022] Open
Abstract
Myelin sheath thickness is precisely regulated and essential for rapid propagation of action potentials along myelinated axons. In the peripheral nervous system, extrinsic signals from the axonal protein neuregulin 1 (NRG1) type III regulate Schwann cell fate and myelination. Here we ask if modulating NRG1 type III levels in neurons would restore myelination in a model of congenital hypomyelinating neuropathy (CHN). Using a mouse model of CHN, we improved the myelination defects by early overexpression of NRG1 type III. Surprisingly, the improvement was independent from the upregulation of Egr2 or essential myelin genes. Rather, we observed the activation of MAPK/ERK and other myelin genes such as peripheral myelin protein 2 and oligodendrocyte myelin glycoprotein. We also confirmed that the permanent activation of MAPK/ERK in Schwann cells has detrimental effects on myelination. Our findings demonstrate that the modulation of axon-to-glial NRG1 type III signaling has beneficial effects and improves myelination defects during development in a model of CHN.
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Affiliation(s)
- Sophie Belin
- Hunter James Kelly Research Institute, University at Buffalo, Buffalo, NY, USA
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York, USA
| | - Francesca Ornaghi
- Hunter James Kelly Research Institute, University at Buffalo, Buffalo, NY, USA
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan, Italy
- SR-TIGET, IRCCS, San Raffaele Scientific Institute, Milan, Italy
| | - Ghjuvan’Ghjacumu Shackleford
- Hunter James Kelly Research Institute, University at Buffalo, Buffalo, NY, USA
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Jie Wang
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Cristina Scapin
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan, Italy
| | | | - Nicholas Silvestri
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Neil Robertson
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Courtney Williamson
- Hunter James Kelly Research Institute, University at Buffalo, Buffalo, NY, USA
| | - Akihiro Ishii
- Department of Neuroscience, University of Connecticut Medical School, Farmington, CT, USA
| | - Carla Taveggia
- Division of Neuroscience, San Raffaele Scientific Institute, Milan, Italy
| | - John Svaren
- Waisman Center, University of Wisconsin–Madison, Madison, WI, USA
| | - Rashmi Bansal
- Department of Neuroscience, University of Connecticut Medical School, Farmington, CT, USA
| | - Markus H Schwab
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
- Department of Cellular Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Klaus Nave
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Pietro Fratta
- Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, Queen Square, London, UK
| | - Maurizio D’Antonio
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan, Italy
| | - Yannick Poitelon
- Department of Neuroscience and Experimental Therapeutics, Albany Medical College, Albany, New York, USA
| | - M Laura Feltri
- Hunter James Kelly Research Institute, University at Buffalo, Buffalo, NY, USA
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan, Italy
| | - Lawrence Wrabetz
- Hunter James Kelly Research Institute, University at Buffalo, Buffalo, NY, USA
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan, Italy
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27
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Diseases of connexins expressed in myelinating glia. Neurosci Lett 2019; 695:91-99. [DOI: 10.1016/j.neulet.2017.05.037] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 05/15/2017] [Accepted: 05/19/2017] [Indexed: 11/23/2022]
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28
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Papaneophytou CP, Georgiou E, Karaiskos C, Sargiannidou I, Markoullis K, Freidin MM, Abrams CK, Kleopa KA. Regulatory role of oligodendrocyte gap junctions in inflammatory demyelination. Glia 2018; 66:2589-2603. [PMID: 30325069 PMCID: PMC6519212 DOI: 10.1002/glia.23513] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 06/20/2018] [Accepted: 06/25/2018] [Indexed: 12/27/2022]
Abstract
Gap junctions (GJs) coupling oligodendrocytes to astrocytes and to other oligodendrocytes are formed mainly by connexin47 (Cx47) and a smaller portion by connexin32 (Cx32). Mutations in both connexins cause inherited demyelinating disorders, but their expression is also disrupted in multiple sclerosis (MS). To clarify whether the loss of either Cx47 or Cx32 could modify the outcome of inflammation and myelin loss, we induced experimental autoimmune encephalomyelitis (EAE) in fully backcrossed Cx32 knockout (KO) and Cx47KO mice and compared their outcome with wild type (WT, C57BI/6 N) mice. Cx47KO EAE mice developed the most severe phenotype assessed by clinical scores and behavioral testing, followed by Cx32KO and WT mice. Cx47KO more than Cx32KO EAE mice developed more microglial activation, myelin, and axonal loss than did WT mice. Oligodendrocyte apoptosis and precursor proliferation was also higher in Cx47KO than in Cx32KO or WT EAE mice. Similarly, blood-spinal cord barrier (BSCB) disruption and inflammatory infiltrates of macrophages, T- and B-cells were more severe in Cx47KO than either Cx32KO or WT EAE groups. Finally, expression profiling revealed that several proinflammatory cytokines were higher at the peak of inflammation in the Cx47KO mice and persisted at later stages of EAE in contrast to reduction of their levels in WT EAE mice. Thus, loss of oligodendrocyte GJs aggravates BSCB disruption and inflammatory myelin loss, likely due to dysregulation of proinflammatory cytokines. This mechanism may play an important role in MS brain with reduced connexin expression, as well as in patients with inherited mutations in oligodendrocyte connexins and secondary inflammation.
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MESH Headings
- Animals
- Apoptosis/genetics
- Astrocytes/metabolism
- Astrocytes/pathology
- Blood-Brain Barrier/drug effects
- Blood-Brain Barrier/physiopathology
- Calcium-Binding Proteins/metabolism
- Cell Proliferation/genetics
- Connexins/genetics
- Connexins/metabolism
- Cytokines/metabolism
- Disease Models, Animal
- Encephalomyelitis, Autoimmune, Experimental/chemically induced
- Encephalomyelitis, Autoimmune, Experimental/genetics
- Encephalomyelitis, Autoimmune, Experimental/pathology
- Encephalomyelitis, Autoimmune, Experimental/physiopathology
- Freund's Adjuvant/toxicity
- Gap Junctions/metabolism
- Gap Junctions/pathology
- Gene Expression Regulation/drug effects
- Gene Expression Regulation/genetics
- Gene Expression Regulation/physiology
- Hand Strength/physiology
- Macrophages/pathology
- Mice
- Mice, Inbred C57BL
- Microfilament Proteins/metabolism
- Motor Activity/drug effects
- Motor Activity/genetics
- Myelin-Oligodendrocyte Glycoprotein/toxicity
- Oligodendroglia/metabolism
- Oligodendroglia/pathology
- Peptide Fragments/toxicity
- Gap Junction beta-1 Protein
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Affiliation(s)
- Christos P. Papaneophytou
- Neuroscience LaboratoryThe Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular MedicineNicosiaCyprus
- Department of Life and Health Sciences, School of Sciences and EngineeringUniversity of NicosiaNicosiaCyprus
| | - Elena Georgiou
- Neuroscience LaboratoryThe Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular MedicineNicosiaCyprus
| | - Christos Karaiskos
- Neuroscience LaboratoryThe Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular MedicineNicosiaCyprus
| | - Irene Sargiannidou
- Neuroscience LaboratoryThe Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular MedicineNicosiaCyprus
| | - Kyriaki Markoullis
- Neuroscience LaboratoryThe Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular MedicineNicosiaCyprus
| | - Mona M. Freidin
- Department of Neurology and RehabilitationUniversity of Illinois ChicagoChicagoIllinois
| | - Charles K. Abrams
- Department of Neurology and RehabilitationUniversity of Illinois ChicagoChicagoIllinois
| | - Kleopas A. Kleopa
- Neuroscience LaboratoryThe Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular MedicineNicosiaCyprus
- Neurology Clinics, The Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular MedicineNicosiaCyprus
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29
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Groh J, Klein D, Berve K, West BL, Martini R. Targeting microglia attenuates neuroinflammation-related neural damage in mice carrying human PLP1
mutations. Glia 2018; 67:277-290. [DOI: 10.1002/glia.23539] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 08/28/2018] [Accepted: 09/11/2018] [Indexed: 02/06/2023]
Affiliation(s)
- Janos Groh
- Department of Neurology, Section of Developmental Neurobiology; University Hospital Wuerzburg; Wuerzburg Germany
| | - Dennis Klein
- Department of Neurology, Section of Developmental Neurobiology; University Hospital Wuerzburg; Wuerzburg Germany
| | - Kristina Berve
- Department of Neurology, Section of Developmental Neurobiology; University Hospital Wuerzburg; Wuerzburg Germany
| | | | - Rudolf Martini
- Department of Neurology, Section of Developmental Neurobiology; University Hospital Wuerzburg; Wuerzburg Germany
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30
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Wies Mancini VSB, Pasquini JM, Correale JD, Pasquini LA. Microglial modulation through colony-stimulating factor-1 receptor inhibition attenuates demyelination. Glia 2018; 67:291-308. [DOI: 10.1002/glia.23540] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 08/22/2018] [Accepted: 08/28/2018] [Indexed: 12/15/2022]
Affiliation(s)
- Victoria Sofía Berenice Wies Mancini
- Department of Biological Chemistry; Institute of Chemistry and Biological Physicochemistry (IQUIFIB), School of Pharmacy and Biochemistry, University of Buenos Aires and National Research Council (CONICET); Buenos Aires Argentina
| | - Juana María Pasquini
- Department of Biological Chemistry; Institute of Chemistry and Biological Physicochemistry (IQUIFIB), School of Pharmacy and Biochemistry, University of Buenos Aires and National Research Council (CONICET); Buenos Aires Argentina
| | | | - Laura Andrea Pasquini
- Department of Biological Chemistry; Institute of Chemistry and Biological Physicochemistry (IQUIFIB), School of Pharmacy and Biochemistry, University of Buenos Aires and National Research Council (CONICET); Buenos Aires Argentina
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31
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Gushchina S, Pryce G, Yip PK, Wu D, Pallier P, Giovannoni G, Baker D, Bo X. Increased expression of colony-stimulating factor-1 in mouse spinal cord with experimental autoimmune encephalomyelitis correlates with microglial activation and neuronal loss. Glia 2018; 66:2108-2125. [PMID: 30144320 DOI: 10.1002/glia.23464] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 04/24/2018] [Accepted: 05/15/2018] [Indexed: 12/18/2022]
Abstract
Microglia contribute to pathophysiology at all stages of multiple sclerosis. Colony-stimulating factor-1 (CSF1) is crucial for microglial proliferation and activation. In this study we measured the CSF1 levels and studied its cellular expression in the mouse spinal cords with experimental autoimmune encephalomyelitis (EAE) to explore the potential contribution of CSF1 in neuronal death. ELISA data showed that CSF1 levels were significantly higher in the spinal cords with acute and chronic EAE than those of normal and adjuvant-injected mice. Immunohistochemical studies demonstrated that CSF1 was expressed in astrocytes and neurons in normal mouse spinal cord. In acute EAE, CSF1 expression was significantly increased, especially in astrocytes in peripheral white matter and large motoneurons. High density of activated microglia was observed in the gray matter where motoneurons expressed high-level CSF1 in acute EAE. Significant large motoneuron loss was seen in chronic EAE and the remaining motoneurons with high-level CSF1 were enwrapped by microglia. Viral vector mediated over-expression of CSF1 in spinal neurons induced profound proliferation and activation of microglia at the injection site and microglia enwrapped CSF1-transduced neurons and their neurites. Significant loss of large CSF1-transduced neurons was seen at 2 and 3 weeks post-viral injection. Demyelination in the CSF1-transduced areas was also significant. These results implicate that CSF1 upregulation in CNS may play an important role in the proliferation and activation of microglia in EAE, contributing to neuroinflammation and neurodegeneration. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Svetlana Gushchina
- Centre for Neuroscience and Trauma, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, E1 2AT, United Kingdom.,Department of Cytology, Histology and Embryology, Ogarev Mordovia State University, Saransk, Republic of Mordovia, 430005, Russia
| | - Gareth Pryce
- Centre for Neuroscience and Trauma, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, E1 2AT, United Kingdom
| | - Ping K Yip
- Centre for Neuroscience and Trauma, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, E1 2AT, United Kingdom
| | - Dongsheng Wu
- School of Engineering and Materials Science, Queen Mary University of London, London, E1 4NS, United Kingdom
| | - Patrick Pallier
- Centre for Neuroscience and Trauma, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, E1 2AT, United Kingdom
| | - Gavin Giovannoni
- Centre for Neuroscience and Trauma, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, E1 2AT, United Kingdom
| | - David Baker
- Centre for Neuroscience and Trauma, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, E1 2AT, United Kingdom
| | - Xuenong Bo
- Centre for Neuroscience and Trauma, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, E1 2AT, United Kingdom
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32
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Fledrich R, Abdelaal T, Rasch L, Bansal V, Schütza V, Brügger B, Lüchtenborg C, Prukop T, Stenzel J, Rahman RU, Hermes D, Ewers D, Möbius W, Ruhwedel T, Katona I, Weis J, Klein D, Martini R, Brück W, Müller WC, Bonn S, Bechmann I, Nave KA, Stassart RM, Sereda MW. Targeting myelin lipid metabolism as a potential therapeutic strategy in a model of CMT1A neuropathy. Nat Commun 2018; 9:3025. [PMID: 30072689 PMCID: PMC6072747 DOI: 10.1038/s41467-018-05420-0] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 06/28/2018] [Indexed: 01/17/2023] Open
Abstract
In patients with Charcot-Marie-Tooth disease 1A (CMT1A), peripheral nerves display aberrant myelination during postnatal development, followed by slowly progressive demyelination and axonal loss during adult life. Here, we show that myelinating Schwann cells in a rat model of CMT1A exhibit a developmental defect that includes reduced transcription of genes required for myelin lipid biosynthesis. Consequently, lipid incorporation into myelin is reduced, leading to an overall distorted stoichiometry of myelin proteins and lipids with ultrastructural changes of the myelin sheath. Substitution of phosphatidylcholine and phosphatidylethanolamine in the diet is sufficient to overcome the myelination deficit of affected Schwann cells in vivo. This treatment rescues the number of myelinated axons in the peripheral nerves of the CMT rats and leads to a marked amelioration of neuropathic symptoms. We propose that lipid supplementation is an easily translatable potential therapeutic approach in CMT1A and possibly other dysmyelinating neuropathies.
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Affiliation(s)
- R Fledrich
- Department of Neurogenetics, Max-Planck-Institute of Experimental Medicine, Göttingen, 37075, Germany.
- Institute of Anatomy, University of Leipzig, Leipzig, 04103, Germany.
- Department of Neuropathology, University Hospital Leipzig, Leipzig, 04103, Germany.
| | - T Abdelaal
- Department of Neurogenetics, Max-Planck-Institute of Experimental Medicine, Göttingen, 37075, Germany
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Göttingen, 37075, Germany
- Chemistry of Natural and Microbial Products Department, Pharmaceutical and Drug Industries Division, National Research Centre, Giza, 12622, Egypt
| | - L Rasch
- Department of Neurogenetics, Max-Planck-Institute of Experimental Medicine, Göttingen, 37075, Germany
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Göttingen, 37075, Germany
| | - V Bansal
- Center for Molecular Neurobiology, Institute of Medical Systems Biology, University Medical Center Hamburg-Eppendorf, Hamburg, 20251, Germany
| | - V Schütza
- Department of Neurogenetics, Max-Planck-Institute of Experimental Medicine, Göttingen, 37075, Germany
- Department of Neuropathology, University Hospital Leipzig, Leipzig, 04103, Germany
| | - B Brügger
- Heidelberg University Biochemistry Center (BZH), Heidelberg, 69120, Germany
| | - C Lüchtenborg
- Heidelberg University Biochemistry Center (BZH), Heidelberg, 69120, Germany
| | - T Prukop
- Department of Neurogenetics, Max-Planck-Institute of Experimental Medicine, Göttingen, 37075, Germany
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Göttingen, 37075, Germany
- Institute of Clinical Pharmacology, University Medical Center Göttingen, Göttingen, 37075, Germany
| | - J Stenzel
- Department of Neurogenetics, Max-Planck-Institute of Experimental Medicine, Göttingen, 37075, Germany
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Göttingen, 37075, Germany
| | - R U Rahman
- Center for Molecular Neurobiology, Institute of Medical Systems Biology, University Medical Center Hamburg-Eppendorf, Hamburg, 20251, Germany
| | - D Hermes
- Department of Neurogenetics, Max-Planck-Institute of Experimental Medicine, Göttingen, 37075, Germany
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Göttingen, 37075, Germany
| | - D Ewers
- Department of Neurogenetics, Max-Planck-Institute of Experimental Medicine, Göttingen, 37075, Germany
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Göttingen, 37075, Germany
| | - W Möbius
- Department of Neurogenetics, Max-Planck-Institute of Experimental Medicine, Göttingen, 37075, Germany
- Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), Göttingen, 37075, Germany
| | - T Ruhwedel
- Department of Neurogenetics, Max-Planck-Institute of Experimental Medicine, Göttingen, 37075, Germany
| | - I Katona
- Institute of Neuropathology, University Hospital Aachen, Aachen, 52074, Germany
| | - J Weis
- Institute of Neuropathology, University Hospital Aachen, Aachen, 52074, Germany
| | - D Klein
- Department of Neurology, Section of Developmental Neurobiology, University Hospital Wuerzburg, Wuerzburg, 97080, Germany
| | - R Martini
- Department of Neurology, Section of Developmental Neurobiology, University Hospital Wuerzburg, Wuerzburg, 97080, Germany
| | - W Brück
- Institute of Neuropathology, University Medical Center Göttingen, Göttingen, 37075, Germany
| | - W C Müller
- Department of Neuropathology, University Hospital Leipzig, Leipzig, 04103, Germany
| | - S Bonn
- Center for Molecular Neurobiology, Institute of Medical Systems Biology, University Medical Center Hamburg-Eppendorf, Hamburg, 20251, Germany
- German Center for Neurodegenerative Diseases, Tübingen, 72076, Germany
| | - I Bechmann
- Institute of Anatomy, University of Leipzig, Leipzig, 04103, Germany
| | - K A Nave
- Department of Neurogenetics, Max-Planck-Institute of Experimental Medicine, Göttingen, 37075, Germany.
| | - R M Stassart
- Department of Neurogenetics, Max-Planck-Institute of Experimental Medicine, Göttingen, 37075, Germany.
- Department of Neuropathology, University Hospital Leipzig, Leipzig, 04103, Germany.
- Institute of Neuropathology, University Medical Center Göttingen, Göttingen, 37075, Germany.
| | - M W Sereda
- Department of Neurogenetics, Max-Planck-Institute of Experimental Medicine, Göttingen, 37075, Germany.
- Department of Clinical Neurophysiology, University Medical Center Göttingen, Göttingen, 37075, Germany.
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33
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Zhang X, Li C, Fowler SC, Zhang Z, Blagg BSJ, Dobrowsky RT. Targeting Heat Shock Protein 70 to Ameliorate c-Jun Expression and Improve Demyelinating Neuropathy. ACS Chem Neurosci 2018; 9:381-390. [PMID: 29120605 DOI: 10.1021/acschemneuro.7b00377] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Increased expression of the c-jun transcription factor occurs in a variety of human neuropathies and is critical in promoting Schwann cell (SC) dedifferentiation and loss of the myelinated phenotype. Using cell culture models, we previously identified KU-32 as a novobiocin-based C-terminal heat shock protein 90 (Hsp90) inhibitor that decreased c-jun expression and the extent of demyelination. Additional chemical optimization has yielded KU-596 as a neuroprotective novologue whose mechanistic efficacy to improve a metabolic neuropathy requires the expression of Hsp70. The current study examined whether KU-596 therapy could decrease c-jun expression and improve motor function in an inducible transgenic model of a SC-specific demyelinating neuropathy (MPZ-Raf mice). Treating MPZ-Raf mice with tamoxifen activates the MAPK kinase pathway, increases c-jun expression and produces a profound demyelinating neuropathy characterized by a loss of motor function and paraparesis. KU-596 therapy did not interfere with MAPK activation but reduced c-jun expression, significantly improved motor performance, and ameliorated the extent of peripheral nerve demyelination in both prevention and intervention studies. Hsp70 was necessary for the drug's neuroprotective efficacy since MPZ-Raf × Hsp70 knockout mice did not respond to KU-596 therapy. Collectively, our data indicate that modulating Hsp70 may provide a novel therapeutic approach to attenuate SC c-jun expression and ameliorate the onset of certain demyelinating neuropathies in humans.
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Affiliation(s)
- Xinyue Zhang
- Department
of Pharmacology and Toxicology and ‡Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Chengyuan Li
- Department
of Pharmacology and Toxicology and ‡Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Stephen C. Fowler
- Department
of Pharmacology and Toxicology and ‡Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Zheng Zhang
- Department
of Pharmacology and Toxicology and ‡Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Brian S. J. Blagg
- Department
of Pharmacology and Toxicology and ‡Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Rick T. Dobrowsky
- Department
of Pharmacology and Toxicology and ‡Department of Medicinal Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
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Jang SY, Yoon BA, Shin YK, Yun SH, Jo YR, Choi YY, Ahn M, Shin T, Park JI, Kim JK, Park HT. Schwann cell dedifferentiation-associated demyelination leads to exocytotic myelin clearance in inflammatory segmental demyelination. Glia 2017; 65:1848-1862. [DOI: 10.1002/glia.23200] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 07/01/2017] [Accepted: 07/23/2017] [Indexed: 02/03/2023]
Affiliation(s)
- So Young Jang
- Department of Physiology, Peripheral Neuropathy Research Center, College of Medicine; Dong-A University; Busan 49201 Republic of Korea
| | - Byeol-A Yoon
- Department of Neurology, Peripheral Neuropathy Research Center, College of Medicine; Dong-A University; Busan 49201 Republic of Korea
| | - Yoon Kyung Shin
- Department of Physiology, Peripheral Neuropathy Research Center, College of Medicine; Dong-A University; Busan 49201 Republic of Korea
| | - Seoug Hoon Yun
- Department of Biochemistry, Peripheral Neuropathy Research Center, College of Medicine; Dong-A University; Busan 49201 Republic of Korea
| | - Young Rae Jo
- Department of Neurology, Peripheral Neuropathy Research Center, College of Medicine; Dong-A University; Busan 49201 Republic of Korea
| | - Yun Young Choi
- Department of Biochemistry, Peripheral Neuropathy Research Center, College of Medicine; Dong-A University; Busan 49201 Republic of Korea
| | - Meejung Ahn
- Department of Veterinary Anatomy, College of Veterinary Medicine and Veterinary Medical Research Institute; JeJu National University; Jeju 63243 Republic of Korea
| | - Taekyun Shin
- Department of Veterinary Anatomy, College of Veterinary Medicine and Veterinary Medical Research Institute; JeJu National University; Jeju 63243 Republic of Korea
| | - Joo In Park
- Department of Biochemistry, Peripheral Neuropathy Research Center, College of Medicine; Dong-A University; Busan 49201 Republic of Korea
| | - Jong Kuk Kim
- Department of Neurology, Peripheral Neuropathy Research Center, College of Medicine; Dong-A University; Busan 49201 Republic of Korea
| | - Hwan Tae Park
- Department of Physiology, Peripheral Neuropathy Research Center, College of Medicine; Dong-A University; Busan 49201 Republic of Korea
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35
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Cattin AL, Lloyd AC. The multicellular complexity of peripheral nerve regeneration. Curr Opin Neurobiol 2016; 39:38-46. [PMID: 27128880 DOI: 10.1016/j.conb.2016.04.005] [Citation(s) in RCA: 150] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 03/31/2016] [Accepted: 04/13/2016] [Indexed: 12/20/2022]
Abstract
Peripheral nerves show a remarkable ability to regenerate following a transection injury. Downstream of the cut, the axons degenerate and so to regenerate the nerve, the severed axons need to regrow back to their targets and regain function. This requires the axons to navigate through two different environments. (1) The bridge of new tissue that forms between the two nerve stumps and (2) the distal stump of the nerve that remains associated with the target tissues. This involves distinct, complex multicellular responses that guide and sustain axonal regrowth. These processes have important implications for our understanding of the regeneration of an adult tissue and have parallels to aspects of tumour formation and spread.
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Affiliation(s)
- Anne-Laure Cattin
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Alison C Lloyd
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK; UCL Cancer Institute, University College London, Gower Street, London WC1E 6BT, UK.
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36
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Rosberg MR, Alvarez S, Klein D, Nielsen FC, Martini R, Levinson SR, Krarup C, Moldovan M. Progression of motor axon dysfunction and ectopic Nav1.8 expression in a mouse model of Charcot-Marie-Tooth disease 1B. Neurobiol Dis 2016; 93:201-14. [PMID: 27215377 DOI: 10.1016/j.nbd.2016.05.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 05/11/2016] [Accepted: 05/18/2016] [Indexed: 12/13/2022] Open
Abstract
Mice heterozygously deficient for the myelin protein P0 gene (P0+/-) develop a slowly progressing neuropathy modeling demyelinating Charcot-Marie-Tooth disease (CMT1B). The aim of the study was to investigate the long-term progression of motor dysfunction in P0+/- mice at 3, 7, 12 and 20months. By comparison with WT littermates, P0+/- showed a decreasing motor performance with age. This was associated with a progressive reduction in amplitude and increase in latency of the plantar compound muscle action potential (CMAP) evoked by stimulation of the tibial nerve at ankle. This progressive functional impairment was in contrast to the mild demyelinating neuropathy of the tibial nerve revealed by histology. "Threshold-tracking" studies showed impaired motor axon excitability in P0+/- from 3months. With time, there was a progressive reduction in threshold deviations during both depolarizing and hyperpolarizing threshold electrotonus associated with increasing resting I/V slope and increasing strength-duration time constant. These depolarizing features in excitability in P0+/- as well as the reduced CMAP amplitude were absent in P0+/- NaV1.8 knockouts, and could be acutely reversed by selective pharmacologic block of NaV1.8 in P0+/-. Mathematical modeling indicated an association of altered passive cable properties with a depolarizing shift in resting membrane potential and increase in the persistent Na(+) current in P0+/-. Our data suggest that ectopic NaV1.8 expression precipitates depolarizing conduction failure in CMT1B, and that motor axon dysfunction in demyelinating neuropathy is pharmacologically reversible.
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Affiliation(s)
- Mette R Rosberg
- Institute of Neuroscience and Pharmacology, University of Copenhagen, Denmark; Department of Clinical Neurophysiology, The Neuroscience Center, Copenhagen University Hospital (Rigshospitalet), Denmark
| | - Susana Alvarez
- Institute of Neuroscience and Pharmacology, University of Copenhagen, Denmark; Department of Clinical Neurophysiology, The Neuroscience Center, Copenhagen University Hospital (Rigshospitalet), Denmark
| | - Dennis Klein
- Neurology, Developmental Neurobiology, University of Würzburg, Germany
| | | | - Rudolf Martini
- Neurology, Developmental Neurobiology, University of Würzburg, Germany
| | - S Rock Levinson
- University of Colorado, Denver, Physiology and Biophysics, United States
| | - Christian Krarup
- Institute of Neuroscience and Pharmacology, University of Copenhagen, Denmark; Department of Clinical Neurophysiology, The Neuroscience Center, Copenhagen University Hospital (Rigshospitalet), Denmark
| | - Mihai Moldovan
- Institute of Neuroscience and Pharmacology, University of Copenhagen, Denmark; Department of Clinical Neurophysiology, The Neuroscience Center, Copenhagen University Hospital (Rigshospitalet), Denmark
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37
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Chitu V, Gokhan Ş, Nandi S, Mehler MF, Stanley ER. Emerging Roles for CSF-1 Receptor and its Ligands in the Nervous System. Trends Neurosci 2016; 39:378-393. [PMID: 27083478 DOI: 10.1016/j.tins.2016.03.005] [Citation(s) in RCA: 228] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 03/07/2016] [Accepted: 03/09/2016] [Indexed: 02/06/2023]
Abstract
The colony-stimulating factor-1 receptor (CSF-1R) kinase regulates tissue macrophage homeostasis, osteoclastogenesis, and Paneth cell development. However, recent studies in mice have revealed that CSF-1R signaling directly controls the development and maintenance of microglia, and cell autonomously regulates neuronal differentiation and survival. While the CSF-1R-cognate ligands, CSF-1 and interleukin-34 (IL-34) compete for binding to the CSF-1R, they are expressed in a largely non-overlapping manner by mature neurons. The recent identification of a dominantly inherited, adult-onset, progressive dementia associated with inactivating mutations in the CSF-1R highlights the importance of CSF-1R signaling in the brain. We review the roles of the CSF-1R and its ligands in microglial and neural development and function, and their relevance to our understanding of neurodegenerative disease.
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Affiliation(s)
- Violeta Chitu
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Şölen Gokhan
- Institute for Brain Disorders and Neural Regeneration, Departments of Neurology, Neuroscience, and Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Sayan Nandi
- Departments of Neuroscience and Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Mark F Mehler
- Institute for Brain Disorders and Neural Regeneration, Departments of Neurology, Neuroscience, and Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - E Richard Stanley
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
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38
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Martini R, Willison H. Neuroinflammation in the peripheral nerve: Cause, modulator, or bystander in peripheral neuropathies? Glia 2016; 64:475-86. [PMID: 26250643 PMCID: PMC4832258 DOI: 10.1002/glia.22899] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 07/21/2015] [Accepted: 07/22/2015] [Indexed: 12/15/2022]
Abstract
The role of innate and adaptive inflammation as a primary driver or modifier of neuropathy in premorbidly normal nerves, and as a critical player in amplifying neuropathies of other known causes (e.g., genetic, metabolic) is incompletely understood and under-researched, despite unmet clinical need. Also, cellular and humoral components of the adaptive and innate immune system are substantial disease modifying agents in the context of neuropathies and, at least in some neuropathies, there is an identified tight interrelationship between both compartments of the immune system. Additionally, the quadruple relationship between Schwann cell, axon, macrophage, and endoneurial fibroblast, with their diverse membrane bound and soluble signalling systems, forms a distinct focus for investigation in nerve diseases with inflammation secondary to Schwann cell mutations and possibly others. Identification of key immunological effector pathways that amplify neuropathic features and associated clinical symptomatology including pain should lead to realistic and timely possibilities for translatable therapeutic interventions using existing immunomodulators, alongside the development of novel therapeutic targets.
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Affiliation(s)
- Rudolf Martini
- Department of NeurologyDevelopmental Neurobiology, University Hospital WürzburgWürzburgD‐97080Germany
| | - Hugh Willison
- Institute of Infection, Immunity and Inflammation College of Medical Veterinary and Life Sciences, Glasgow Biomedical Research Centre, University of GlasgowGlasgowG12 8TA
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39
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Groh J, Basu R, Stanley ER, Martini R. Cell-Surface and Secreted Isoforms of CSF-1 Exert Opposing Roles in Macrophage-Mediated Neural Damage in Cx32-Deficient Mice. J Neurosci 2016; 36:1890-901. [PMID: 26865613 PMCID: PMC4748074 DOI: 10.1523/jneurosci.3427-15.2016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 12/01/2015] [Accepted: 12/24/2015] [Indexed: 12/13/2022] Open
Abstract
Previous studies in myelin-mutant mouse models of the inherited and incurable nerve disorder, Charcot-Marie-Tooth (CMT) neuropathy, have demonstrated that low-grade secondary inflammation implicating phagocytosing macrophages amplifies demyelination, Schwann cell dedifferentiation and perturbation of axons. The cytokine colony stimulating factor-1 (CSF-1) acts as an important regulator of these macrophage-related disease mechanisms, as genetic and pharmacologic approaches to block the CSF-1/CSF-1R signaling result in a significant alleviation of pathological alterations in mutant peripheral nerves. In mouse models of CMT1A and CMT1X, as well as in human biopsies, CSF-1 is predominantly expressed by endoneurial fibroblasts, which are closely associated with macrophages, suggesting local stimulatory mechanisms. Here we investigated the impact of cell-surface and secreted isoforms of CSF-1 on macrophage-related disease in connexin32-deficient (Cx32def) mice, a mouse model of CMT1X. Our present observations suggest that the secreted proteoglycan isoform (spCSF-1) is predominantly expressed by fibroblasts, whereas the membrane-spanning cell-surface isoform (csCSF-1) is expressed by macrophages. Using crossbreeding approaches to selectively restore or overexpress distinct isoforms in CSF-1-deficient (osteopetrotic) Cx32def mice, we demonstrate that both isoforms equally regulate macrophage numbers dose-dependently. However, spCSF-1 mediates macrophage activation and macrophage-related neural damage, whereas csCSF-1 inhibits macrophage activation and attenuates neuropathy. These results further corroborate the important role of secondary inflammation in mouse models of CMT1 and might identify specific targets for therapeutic approaches to modulate innate immune reactions. SIGNIFICANCE STATEMENT Mouse models of Charcot-Marie-Tooth neuropathy have indicated that low-grade secondary inflammation involving phagocytosing macrophages amplifies demyelination, Schwann cell dedifferentiation, and perturbation of axons. The recruitment and pathogenic activation of detrimental macrophages is regulated by CSF-1, a cytokine that is mostly expressed by fibroblasts in the diseased nerve and exists in three isoforms. We show that the cell-surface and secreted isoforms of CSF-1 have opposing effects on macrophage activation and disease progression in a mouse model of CMT1X. These insights into opposing functions of disease-modulating cytokine isoforms might enable the development of specific therapeutic approaches.
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Affiliation(s)
- Janos Groh
- Department of Neurology, Developmental Neurobiology, University Hospital Wuerzburg, D-97080 Wuerzburg, Germany, and
| | - Ranu Basu
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York 10461
| | - E Richard Stanley
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York 10461
| | - Rudolf Martini
- Department of Neurology, Developmental Neurobiology, University Hospital Wuerzburg, D-97080 Wuerzburg, Germany, and
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40
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Affiliation(s)
- Steven S Scherer
- Perelman School of Medicine at the University of Pennsylvania, USA
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41
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Jang SY, Shin YK, Park SY, Park JY, Lee HJ, Yoo YH, Kim JK, Park HT. Autophagic myelin destruction by Schwann cells during Wallerian degeneration and segmental demyelination. Glia 2015; 64:730-42. [PMID: 26712109 DOI: 10.1002/glia.22957] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 11/26/2015] [Accepted: 12/02/2015] [Indexed: 01/17/2023]
Abstract
As lysosomal hydrolysis has long been suggested to be responsible for myelin clearance after peripheral nerve injury, in this study, we investigated the possible role of autophagolysosome formation in myelin phagocytosis by Schwann cells and its final contribution to nerve regeneration. We found that the canonical formation of autophagolysosomes was induced in demyelinating Schwann cells after injury, and the inhibition of autophagy via Schwann cell-specific knockout of the atg7 gene or pharmacological intervention of lysosomal function caused a significant delay in myelin clearance. However, Schwann cell dedifferentiation, as demonstrated by extracellular signal-regulated kinase activation and c-Jun induction, and redifferentiation were not significantly affected, and thus the entire repair program progressed normally in atg7 knockout mice. Finally, autophagic Schwann cells were also found during segmental demyelination in a mouse model of inflammatory peripheral neuropathy. Together, our findings suggest that autophagy is the self-myelin destruction mechanism of Schwann cells, but mechanistically, it is a process distinct from Schwann cell plasticity for nerve repair.
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Affiliation(s)
- So Young Jang
- Department of Physiology, Mitochondria Hub Regulation Center, Dong-a University, Busan, Korea
| | - Yoon Kyung Shin
- Department of Physiology, Mitochondria Hub Regulation Center, Dong-a University, Busan, Korea
| | - So Young Park
- Department of Pharmacology, Mitochondria Hub Regulation Center, Dong-a University, Busan, Korea
| | - Joo Youn Park
- Department of Physiology, Mitochondria Hub Regulation Center, Dong-a University, Busan, Korea
| | - Hye Jeong Lee
- Department of Pharmacology, Mitochondria Hub Regulation Center, Dong-a University, Busan, Korea
| | | | - Jong Kuk Kim
- Neurology, College of Medicine, Dong-a University, Busan, Korea
| | - Hwan Tae Park
- Department of Physiology, Mitochondria Hub Regulation Center, Dong-a University, Busan, Korea
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42
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Klein D, Martini R. Myelin and macrophages in the PNS: An intimate relationship in trauma and disease. Brain Res 2015; 1641:130-138. [PMID: 26631844 DOI: 10.1016/j.brainres.2015.11.033] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 11/18/2015] [Accepted: 11/19/2015] [Indexed: 01/08/2023]
Abstract
Macrophages of the peripheral nervous system belong to the so-called tissue macrophages, with multiple functions during injury and disease. Their origin during ontogeny has not yet been completely resolved, but it is clear that upon injury and disease conditions, they are supplemented by hematopoietic derivatives. In the peripheral nervous system, the most abundantly investigated scenario in which resident and infiltrating macrophages are involved is the so-called "Wallerian degeneration", a complex degenerative process where macrophages exhibit mostly beneficial functions by phagocytosing myelin and axonal remnants. Of special interest is the implication of macrophages in inflammatory nerve diseases, like acute Guillain-Barré syndromes and its permanent variant, chronic inflammatory demyelinating polyneuropathy, where macrophages are supposed to be substantial (co-)mediators of the diseases. In inherited peripheral neuropathies nerve macrophages possess a clear disease-amplifying function. In the corresponding animal models, a coordinated interplay between mutant Schwann cells, macrophages, endoneurial fibroblasts and the target structure, myelin, emerged. Along this process, a newly discovered disease mechanism mediated by macrophages is the dedifferentiation of myelinating Schwann cells. As macrophages are amplifiers of the genetically-mediated, non-curable diseases, targeting the mechanisms of their activation might be a promising strategy to treat these disorders. This article is part of a Special Issue entitled SI: Myelin Evolution.
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Affiliation(s)
- Dennis Klein
- University Hospital Würzburg, Department of Neurology, Developmental Neurobiology, Josef-Schneider Str. 11, 97080 Würzburg, Germany
| | - Rudolf Martini
- University Hospital Würzburg, Department of Neurology, Developmental Neurobiology, Josef-Schneider Str. 11, 97080 Würzburg, Germany.
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43
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Jha MK, Lee WH, Suk K. Functional polarization of neuroglia: Implications in neuroinflammation and neurological disorders. Biochem Pharmacol 2015; 103:1-16. [PMID: 26556658 DOI: 10.1016/j.bcp.2015.11.003] [Citation(s) in RCA: 186] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Accepted: 11/02/2015] [Indexed: 12/15/2022]
Abstract
Recent neuroscience research has established the adult brain as a dynamic organ having a unique ability to undergo changes with time. Neuroglia, especially microglia and astrocytes, provide dynamicity to the brain. Activation of these glial cells is a major component of the neuroinflammatory responses underlying brain injury and neurodegeneration. Glial cells execute functional reaction programs in response to diverse microenvironmental signals manifested by neuropathological conditions. Activated microglia exist along a continuum of two functional states of polarization namely M1-type (classical/proinflammatory activation) and M2-type (alternative/anti-inflammatory activation) as in macrophages. The balance between classically and alternatively activated microglial phenotypes influences disease progression in the CNS. The classically activated state of microglia drives the neuroinflammatory response and mediates the detrimental effects on neurons, whereas in their alternative activation state, which is apparently a beneficial activation state, the microglia play a crucial role in tissue maintenance and repair. Likewise, in response to immune or inflammatory microenvironments astrocytes also adopt neurotoxic or neuroprotective phenotypes. Reactive astrocytes exhibit two distinctive functional phenotypes defined by pro- or anti-inflammatory gene expression profile. In this review, we have thoroughly covered recent advances in the understanding of the functional polarization of brain and peripheral glia and its implications in neuroinflammation and neurological disorders. The identifiable phenotypes adopted by neuroglia in response to specific insult or injury can be exploited as promising diagnostic markers of neuroinflammatory diseases. Furthermore, harnessing the beneficial effects of the polarized glia could undoubtedly pave the way for the formulation of novel glia-based therapeutic strategies for diverse neurological disorders.
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Affiliation(s)
- Mithilesh Kumar Jha
- Department of Pharmacology, Brain Science & Engineering Institute, BK21 Plus KNU Biomedical Convergence Program, Kyungpook National University School of Medicine, Daegu, Republic of Korea
| | - Won-Ha Lee
- School of Life Sciences, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu, Republic of Korea
| | - Kyoungho Suk
- Department of Pharmacology, Brain Science & Engineering Institute, BK21 Plus KNU Biomedical Convergence Program, Kyungpook National University School of Medicine, Daegu, Republic of Korea.
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44
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Klein D, Patzkó Á, Schreiber D, van Hauwermeiren A, Baier M, Groh J, West BL, Martini R. Targeting the colony stimulating factor 1 receptor alleviates two forms of Charcot-Marie-Tooth disease in mice. Brain 2015; 138:3193-205. [PMID: 26297559 DOI: 10.1093/brain/awv240] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 06/26/2015] [Indexed: 01/05/2023] Open
Abstract
See Scherer (doi:10.1093/awv279) for a scientific commentary on this article.Charcot-Marie-Tooth type 1 neuropathies are inherited disorders of the peripheral nervous system caused by mutations in Schwann cell-related genes. Typically, no causative cure is presently available. Previous preclinical data of our group highlight the low grade, secondary inflammation common to distinct Charcot-Marie-Tooth type 1 neuropathies as a disease amplifier. In the current study, we have tested one of several available clinical agents targeting macrophages through its inhibition of the colony stimulating factor 1 receptor (CSF1R). We here show that in two distinct mouse models of Charcot-Marie-Tooth type 1 neuropathies, the systemic short- and long-term inhibition of CSF1R by oral administration leads to a robust decline in nerve macrophage numbers by ∼70% and substantial reduction of the typical histopathological and functional alterations. Interestingly, in a model for the dominant X-linked form of Charcot-Marie-Tooth type 1 neuropathy, the second most common form of the inherited neuropathies, macrophage ablation favours maintenance of axonal integrity and axonal resprouting, leading to preserved muscle innervation, increased muscle action potential amplitudes and muscle strengths in the range of wild-type mice. In another model mimicking a mild, demyelination-related Charcot-Marie-Tooth type 1 neuropathy caused by reduced P0 (MPZ) gene dosage, macrophage blockade causes an improved preservation of myelin, increased muscle action potential amplitudes, improved nerve conduction velocities and ameliorated muscle strength. These observations suggest that disease-amplifying macrophages can produce multiple adverse effects in the affected nerves which likely funnel down to common clinical features. Surprisingly, treatment of mouse models mimicking Charcot-Marie-Tooth type 1A neuropathy also caused macrophage blockade, but did not result in neuropathic or clinical improvements, most likely due to the late start of treatment of this early onset disease model. In summary, our study shows that targeting peripheral nerve macrophages by an orally administered inhibitor of CSF1R may offer a highly efficacious and safe treatment option for at least two distinct forms of the presently non-treatable Charcot-Marie-Tooth type 1 neuropathies.
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Affiliation(s)
- Dennis Klein
- 1 Department of Neurology, Developmental Neurobiology, University Hospital Würzburg Josef-Schneider Str. 11, D-97080 Würzburg, Germany
| | - Ágnes Patzkó
- 1 Department of Neurology, Developmental Neurobiology, University Hospital Würzburg Josef-Schneider Str. 11, D-97080 Würzburg, Germany
| | - David Schreiber
- 1 Department of Neurology, Developmental Neurobiology, University Hospital Würzburg Josef-Schneider Str. 11, D-97080 Würzburg, Germany
| | - Anemoon van Hauwermeiren
- 1 Department of Neurology, Developmental Neurobiology, University Hospital Würzburg Josef-Schneider Str. 11, D-97080 Würzburg, Germany
| | - Michaela Baier
- 1 Department of Neurology, Developmental Neurobiology, University Hospital Würzburg Josef-Schneider Str. 11, D-97080 Würzburg, Germany
| | - Janos Groh
- 1 Department of Neurology, Developmental Neurobiology, University Hospital Würzburg Josef-Schneider Str. 11, D-97080 Würzburg, Germany
| | | | - Rudolf Martini
- 1 Department of Neurology, Developmental Neurobiology, University Hospital Würzburg Josef-Schneider Str. 11, D-97080 Würzburg, Germany
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45
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Patzig J, Kusch K, Fledrich R, Eichel MA, Lüders KA, Möbius W, Sereda MW, Nave KA, Martini R, Werner HB. Proteolipid protein modulates preservation of peripheral axons and premature death when myelin protein zero is lacking. Glia 2015; 64:155-74. [PMID: 26393339 DOI: 10.1002/glia.22922] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 09/04/2015] [Indexed: 12/23/2022]
Abstract
Protein zero (P0) is the major structural component of peripheral myelin. Lack of this adhesion protein from Schwann cells causes a severe dysmyelinating neuropathy with secondary axonal degeneration in humans with the neuropathy Dejerine-Sottas syndrome (DSS) and in the corresponding mouse model (P0(null)-mice). In the mammalian CNS, the tetraspan-membrane protein PLP is the major structural myelin constituent and required for the long-term preservation of myelinated axons, which fails in hereditary spastic paraplegia (SPG type-2) and the relevant mouse model (Plp(null)-mice). The Plp-gene is also expressed in Schwann cells but PLP is of very low abundance in normal peripheral myelin; its function has thus remained enigmatic. Here we show that the abundance of PLP but not of other tetraspan myelin proteins is strongly increased in compact peripheral myelin of P0(null)-mice. To determine the functional relevance of PLP expression in the absence of P0, we generated P0(null)*Plp(null)-double-mutant mice. Compared with either single-mutant, P0(null)*Plp(null)-mice display impaired nerve conduction, reduced motor functions, and premature death. At the morphological level, axonal segments were frequently non-myelinated but in a one-to-one relationship with a hypertrophic Schwann cell. Importantly, axonal numbers were reduced in the vital phrenic nerve of P0(null)*Plp(null)-mice. In the absence of P0, thus, PLP also contributes to myelination by Schwann cells and to the preservation of peripheral axons. These data provide a link between the Schwann cell-dependent support of peripheral axons and the oligodendrocyte-dependent support of central axons.
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Affiliation(s)
- Julia Patzig
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Kathrin Kusch
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Robert Fledrich
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Maria A Eichel
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Katja A Lüders
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Wiebke Möbius
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany.,Center for Nanoscale Microscopy and Molecular Physiology of the Brain, Göttingen, Germany
| | - Michael W Sereda
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany.,Department of Clinical Neurophysiology, University Medical Center, Göttingen, Germany
| | - Klaus-Armin Nave
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Rudolf Martini
- Department of Neurology, Developmental Neurobiology, University Hospital, Würzburg, Germany
| | - Hauke B Werner
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
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