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Patel AA, Kim H, Ramesh R, Marquez A, Faraj MM, Antikainen H, Lee AS, Torres A, Khawaja IM, Heffernan C, Bonder EM, Maurel P, Svaren J, Son YJ, Dobrowolski R, Kim HA. TFEB/3 Govern Repair Schwann Cell Generation and Function Following Peripheral Nerve Injury. J Neurosci 2024; 44:e0198242024. [PMID: 39054068 PMCID: PMC11358533 DOI: 10.1523/jneurosci.0198-24.2024] [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: 01/24/2024] [Revised: 07/12/2024] [Accepted: 07/15/2024] [Indexed: 07/27/2024] Open
Abstract
TFEB and TFE3 (TFEB/3), key regulators of lysosomal biogenesis and autophagy, play diverse roles depending on cell type. This study highlights a hitherto unrecognized role of TFEB/3 crucial for peripheral nerve repair. Specifically, they promote the generation of progenitor-like repair Schwann cells after axonal injury. In Schwann cell-specific TFEB/3 double knock-out mice of either sex, the TFEB/3 loss disrupts the transcriptomic reprogramming that is essential for the formation of repair Schwann cells. Consequently, mutant mice fail to populate the injured nerve with repair Schwann cells and exhibit defects in axon regrowth, target reinnervation, and functional recovery. TFEB/3 deficiency inhibits the expression of injury-responsive repair Schwann cell genes, despite the continued expression of c-jun, a previously identified regulator of repair Schwann cell function. TFEB/3 binding motifs are enriched in the enhancer regions of injury-responsive genes, suggesting their role in repair gene activation. Autophagy-dependent myelin breakdown is not impaired despite TFEB/3 deficiency. These findings underscore a unique role of TFEB/3 in adult Schwann cells that is required for proper peripheral nerve regeneration.
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Affiliation(s)
- Akash A Patel
- Department of Biological Sciences, Rutgers University, Newark, New Jersey 07102
| | - Hyukmin Kim
- Shriners Hospitals Pediatric Research Center and Department of Neural Science, Temple University, Philadelphia, Pennsylvania 19140
| | - Raghu Ramesh
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin 53705
- Comparative Biomedical Sciences Graduate Program, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Anthony Marquez
- Department of Biological Sciences, Rutgers University, Newark, New Jersey 07102
| | - Moler M Faraj
- Department of Biological Sciences, Rutgers University, Newark, New Jersey 07102
| | - Henri Antikainen
- Department of Biological Sciences, Rutgers University, Newark, New Jersey 07102
| | - Andrew S Lee
- Department of Biological Sciences, Rutgers University, Newark, New Jersey 07102
| | - Adriana Torres
- Department of Biological Sciences, Rutgers University, Newark, New Jersey 07102
| | - Imran M Khawaja
- Department of Biological Sciences, Rutgers University, Newark, New Jersey 07102
| | - Corey Heffernan
- Department of Biological Sciences, Rutgers University, Newark, New Jersey 07102
| | - Edward M Bonder
- Department of Biological Sciences, Rutgers University, Newark, New Jersey 07102
| | - Patrice Maurel
- Department of Biological Sciences, Rutgers University, Newark, New Jersey 07102
| | - John Svaren
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin 53705
- Comparative Biomedical Sciences Graduate Program, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53706
- Department of Comparative Biosciences, School of Veterinary Medicine University of Wisconsin-Madison, Madison, Wisconsin 53705
| | - Young-Jin Son
- Shriners Hospitals Pediatric Research Center and Department of Neural Science, Temple University, Philadelphia, Pennsylvania 19140
- Department of Anatomy and Cell Biology, Temple University, Philadelphia, Pennsylvania 19140
| | - Radek Dobrowolski
- Department of Biological Sciences, Rutgers University, Newark, New Jersey 07102
| | - Haesun A Kim
- Department of Biological Sciences, Rutgers University, Newark, New Jersey 07102
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2
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DAP12 deletion causes age-related motor function impairment but promotes functional recovery after sciatic nerve crush injury. Exp Neurol 2023; 360:114296. [PMID: 36503041 DOI: 10.1016/j.expneurol.2022.114296] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 11/18/2022] [Accepted: 12/07/2022] [Indexed: 12/13/2022]
Abstract
DNAX activating protein of 12 kDa (DAP12)-deficiency mice showed impaired differentiation of oligodendrocytes and reduced myelin in the central nervous system. Whether DAP12 is expressed by Schwann cells and its roles in the peripheral nervous system (PNS) remains unknown. In this study, expression of DAP12 was detected in Schwann cells in vivo and in vitro. The DAP12-knockout (KO) mice showed age-related motor deficits and thinner myelin in the sciatic nerve than WT mice but significantly faster clinical recovery after sciatic nerve crush injury. In sciatic nerves of DAP12 KO and WT mice, proteomic profiles analysis identified 158 differentially expressed proteins (DEPs) at 8-week-old, 29 DEPs at 54-week-old and 33 DEPs at two weeks after crush injury. Typically, of the DEPs at 54-week-old, up-regulated Lgmn and down-regulated RecK and Yap1 were associated with myelin loss in the sciatic nerve of DAP12 KO mice. Upregulation of nicotinamide nucleotide transhydrogenase and haptoglobin were associated with the accumulation of macrophages in the crushed sciatic nerve of DAP12 KO mice. After crush injury, there were significantly more M1 macrophages at one-week and more M2 macrophages at two-week in sciatic nerve of DAP12 KO mice than WT mice, indicating that DAP12 deletion promotes the phenotype conversion of macrophages from M1 to M2. Collectively, our findings suggest that DAP12 may exert dual roles in the PNS including promoting the physiological myelin formation and maintenance of Schwann cells but delaying nerve repair after injury by modulating the recruitment of macrophages and phenotype conversion.
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3
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Schwann cell functions in peripheral nerve development and repair. Neurobiol Dis 2023; 176:105952. [PMID: 36493976 DOI: 10.1016/j.nbd.2022.105952] [Citation(s) in RCA: 43] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 11/23/2022] [Accepted: 12/05/2022] [Indexed: 12/12/2022] Open
Abstract
The glial cell of the peripheral nervous system (PNS), the Schwann cell (SC), counts among the most multifaceted cells of the body. During development, SCs secure neuronal survival and participate in axonal path finding. Simultaneously, they orchestrate the architectural set up of the developing nerves, including the blood vessels and the endo-, peri- and epineurial layers. Perinatally, in rodents, SCs radially sort and subsequently myelinate individual axons larger than 1 μm in diameter, while small calibre axons become organised in non-myelinating Remak bundles. SCs have a vital role in maintaining axonal health throughout life and several specialized SC types perform essential functions at specific locations, such as terminal SC at the neuromuscular junction (NMJ) or SC within cutaneous sensory end organs. In addition, neural crest derived satellite glia maintain a tight communication with the soma of sensory, sympathetic, and parasympathetic neurons and neural crest derivatives are furthermore an indispensable part of the enteric nervous system. The remarkable plasticity of SCs becomes evident in the context of a nerve injury, where SC transdifferentiate into intriguing repair cells, which orchestrate a regenerative response that promotes nerve repair. Indeed, the multiple adaptations of SCs are captivating, but remain often ill-resolved on the molecular level. Here, we summarize and discuss the knowns and unknowns of the vast array of functions that this single cell type can cover in peripheral nervous system development, maintenance, and repair.
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Costa G, Ribeiro FF, Sebastião AM, Muir EM, Vaz SH. Bridging the gap of axonal regeneration in the central nervous system: A state of the art review on central axonal regeneration. Front Neurosci 2022; 16:1003145. [PMID: 36440273 PMCID: PMC9682039 DOI: 10.3389/fnins.2022.1003145] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 10/19/2022] [Indexed: 08/26/2023] Open
Abstract
Neuronal regeneration in the central nervous system (CNS) is an important field of research with relevance to all types of neuronal injuries, including neurodegenerative diseases. The glial scar is a result of the astrocyte response to CNS injury. It is made up of many components creating a complex environment in which astrocytes play various key roles. The glial scar is heterogeneous, diverse and its composition depends upon the injury type and location. The heterogeneity of the glial scar observed in different situations of CNS damage and the consequent implications for axon regeneration have not been reviewed in depth. The gap in this knowledge will be addressed in this review which will also focus on our current understanding of central axonal regeneration and the molecular mechanisms involved. The multifactorial context of CNS regeneration is discussed, and we review newly identified roles for components previously thought to solely play an inhibitory role in central regeneration: astrocytes and p75NTR and discuss their potential and relevance for deciding therapeutic interventions. The article ends with a comprehensive review of promising new therapeutic targets identified for axonal regeneration in CNS and a discussion of novel ways of looking at therapeutic interventions for several brain diseases and injuries.
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Affiliation(s)
- Gonçalo Costa
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
- Faculdade de Medicina, Universidade do Porto, Porto, Portugal
| | - Filipa F. Ribeiro
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| | - Ana M. Sebastião
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| | - Elizabeth M. Muir
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Sandra H. Vaz
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
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5
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Shi YJ, Sheng WJ, Xue MT, Duan FX, Shen L, Ding SQ, Wang QY, Wang R, Lü HZ, Hu JG. Effect of morroniside on the transcriptome profiles of rat in injured spinal cords. Gene 2022; 823:146338. [PMID: 35245640 DOI: 10.1016/j.gene.2022.146338] [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: 11/18/2021] [Revised: 01/16/2022] [Accepted: 02/11/2022] [Indexed: 12/27/2022]
Abstract
We have previously reported that morroniside promoted motor activity after spinal cord injury (SCI) in rats. However, the mechanism by which morroniside induces recovery of injured spinal cord (SC) remains unknown. In the current study, RNA sequencing (RNA-seq) was employed to evaluate changes of gene expressions at the transcriptional level of the injured spinal cords in morroniside-administrated rats. Principal component analysis, analysis of enriched Gene Ontology (GO), enrichment analyses Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and other bioinformatics analyses were executed to distinguish differentially expressed genes (DEGs). The results of RNA-seq confirmed the anti-inflammatory and anti-apoptotic effects of morroniside on injured SC tissues, and provided the basis for additional research of the mechanisms involving the protective effects of morroniside on SCI.
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Affiliation(s)
- Yu-Jiao Shi
- Department of Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, 287 Chang Huai Road, Bengbu 233004, PR China; Anhui Key Laboratory of Tissue Transplantation, Bengbu Medical College, Bengbu 233004, PR China
| | - Wen-Jie Sheng
- Department of Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, 287 Chang Huai Road, Bengbu 233004, PR China; Anhui Key Laboratory of Tissue Transplantation, Bengbu Medical College, Bengbu 233004, PR China
| | - Meng-Tong Xue
- Department of Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, 287 Chang Huai Road, Bengbu 233004, PR China; Anhui Key Laboratory of Tissue Transplantation, Bengbu Medical College, Bengbu 233004, PR China
| | - Fei-Xiang Duan
- Department of Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, 287 Chang Huai Road, Bengbu 233004, PR China; Anhui Key Laboratory of Tissue Transplantation, Bengbu Medical College, Bengbu 233004, PR China
| | - Lin Shen
- Anhui Key Laboratory of Tissue Transplantation, Bengbu Medical College, Bengbu 233004, PR China
| | - Shu-Qin Ding
- Department of Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, 287 Chang Huai Road, Bengbu 233004, PR China; Anhui Key Laboratory of Tissue Transplantation, Bengbu Medical College, Bengbu 233004, PR China
| | - Qi-Yi Wang
- Department of Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, 287 Chang Huai Road, Bengbu 233004, PR China
| | - Rui Wang
- Anhui Key Laboratory of Tissue Transplantation, Bengbu Medical College, Bengbu 233004, PR China
| | - He-Zuo Lü
- Department of Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, 287 Chang Huai Road, Bengbu 233004, PR China; Anhui Key Laboratory of Tissue Transplantation, Bengbu Medical College, Bengbu 233004, PR China; Department of Immunology, Bengbu Medical College, Bengbu 233030, PR China.
| | - Jian-Guo Hu
- Department of Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, 287 Chang Huai Road, Bengbu 233004, PR China; Anhui Key Laboratory of Tissue Transplantation, Bengbu Medical College, Bengbu 233004, PR China.
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6
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Trolese MC, Scarpa C, Melfi V, Fabbrizio P, Sironi F, Rossi M, Bendotti C, Nardo G. Boosting the peripheral immune response in the skeletal muscles improved motor function in ALS transgenic mice. Mol Ther 2022; 30:2760-2784. [PMID: 35477657 PMCID: PMC9372324 DOI: 10.1016/j.ymthe.2022.04.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 04/15/2022] [Accepted: 04/25/2022] [Indexed: 11/26/2022] Open
Abstract
Monocyte chemoattractant protein-1 (MCP1) is one of the most powerful pro-inflammatory chemokines. However, its signalling is pivotal in driving injured axon and muscle regeneration.
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Affiliation(s)
- Maria Chiara Trolese
- Laboratory of Molecular Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri Mario Negri IRCCS, Via Mario Negri 2, 20156 Milan, Italy
| | - Carlotta Scarpa
- Laboratory of Molecular Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri Mario Negri IRCCS, Via Mario Negri 2, 20156 Milan, Italy
| | - Valentina Melfi
- Laboratory of Molecular Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri Mario Negri IRCCS, Via Mario Negri 2, 20156 Milan, Italy
| | - Paola Fabbrizio
- Laboratory of Molecular Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri Mario Negri IRCCS, Via Mario Negri 2, 20156 Milan, Italy
| | - Francesca Sironi
- Laboratory of Molecular Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri Mario Negri IRCCS, Via Mario Negri 2, 20156 Milan, Italy
| | - Martina Rossi
- Laboratory of Molecular Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri Mario Negri IRCCS, Via Mario Negri 2, 20156 Milan, Italy
| | - Caterina Bendotti
- Laboratory of Molecular Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri Mario Negri IRCCS, Via Mario Negri 2, 20156 Milan, Italy;.
| | - Giovanni Nardo
- Laboratory of Molecular Neurobiology, Department of Neuroscience, Istituto di Ricerche Farmacologiche Mario Negri Mario Negri IRCCS, Via Mario Negri 2, 20156 Milan, Italy;.
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Ebenezer GJ, Pena MT, Daniel AS, Truman RW, Adams L, Duthie MS, Wagner K, Zampino S, Tolf E, Tsottles D, Polydefkis M. Mycobacterium leprae induces Schwann cell proliferation and migration in a denervated milieu following intracutaneous excision axotomy in nine-banded armadillos. Exp Neurol 2022; 352:114053. [PMID: 35341747 DOI: 10.1016/j.expneurol.2022.114053] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 02/15/2022] [Accepted: 03/21/2022] [Indexed: 01/23/2023]
Abstract
Nine-banded armadillos develop peripheral neuropathy after experimental Mycobacterium leprae infection that recapitulates human disease. We used an intracutaneous excision axotomy model to assess the effect of infection duration by M. leprae on axonal sprouting and Schwan cell density. 34 armadillos (17 naïve and 17 M. leprae-infected) underwent 3 mm skin biopsies to create an intracutaneous excision axotomy followed by a concentric 4-mm overlapping biopsy 3 and 12-months post M. leprae inoculation. A traditional distal leg biopsy was obtained at 15mo for intraepidermal nerve fiber (IENF) density. Serial skin sections were immunostained against a axons (PGP9.5, GAP43), and Schwann cells (p75, s100) to visualize regenerating nerves. Regenerative axons and proliferation of Schwann cells was measured and the rate of growth at each time point was assessed. Increasing anti-PGL antibody titers and intraneural M. leprae confirmed infection. 15mo following infection, there was evidence of axon loss with reduced distal leg IENF versus naïve armadillos, p < 0.05. This was associated with an increase in Schwann cell density (11,062 ± 2905 vs. 7561 ± 2715 cells/mm3, p < 0.01). Following excisional biopsy epidermal reinnervation increased monotonically at 30, 60 and 90 days; the regeneration rate was highest at 30 days, and decreased at 60 and 90 days. The reinnervation rate was highest among animals infected for 3mo vs those infected for 12mo or naïve animals (mean ± SD, 27.8 ± 7.2 vs.16.2 ± 5.8vs. 15.3 ± 6.5 mm/mm3, p < 0.05). The infected armadillos displayed a sustained Schwann cell proliferation across axotomy time points and duration of infection (3mo:182 ± 26, 12mo: 256 ± 126, naive: 139 ± 49 cells/day, p < 0.05). M. leprae infection is associated with sustained Schwann cell proliferation and distal limb nerve fiber loss. Rates of epidermal reinnervation were highest 3mo after infection and normalized by 12 mo of infection. We postulate that excess Schwann cell proliferation is the main pathogenic process and is deleterious to sensory axons. There is a compensatory initial increase in regeneration rates that may be an attempt to compensate for the injury, but it is not sustained and eventually followed by axon loss. Aberrant Schwann cell proliferation may be a novel therapeutic target to interrupt the pathogenic cascade of M. leprae.
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Affiliation(s)
| | - Maria T Pena
- DHHS/HRSA/HSB/National Hansen's Disease Program, Baton Rouge, LA 70816, USA
| | | | - Richard W Truman
- DHHS/HRSA/HSB/National Hansen's Disease Program, Baton Rouge, LA 70816, USA
| | - Linda Adams
- DHHS/HRSA/HSB/National Hansen's Disease Program, Baton Rouge, LA 70816, USA
| | | | - Kelly Wagner
- Neurology, Johns Hopkins University, Baltimore, MD, USA
| | | | - Eleanor Tolf
- Neurology, Johns Hopkins University, Baltimore, MD, USA
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8
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Pellegatta M, Canevazzi P, Forese MG, Podini P, Valenzano S, Del Carro U, Quattrini A, Taveggia C. ADAM17 Regulates p75 NTR-Mediated Fibrinolysis and Nerve Remyelination. J Neurosci 2022; 42:2433-2447. [PMID: 35110388 PMCID: PMC8944234 DOI: 10.1523/jneurosci.1341-21.2022] [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: 06/28/2021] [Revised: 11/12/2021] [Accepted: 01/03/2022] [Indexed: 11/21/2022] Open
Abstract
We previously reported that a-disintegrin and metalloproteinase (ADAM)17 is a key protease regulating myelin formation. We now describe a role for ADAM17 during the Wallerian degeneration (WD) process. Unexpectedly, we observed that glial ADAM17, by regulating p75NTR processing, cell autonomously promotes remyelination, while neuronal ADAM17 is dispensable. Accordingly, p75NTR abnormally accumulates specifically when ADAM17 is maximally expressed leading to a downregulation of tissue plasminogen activator (tPA) expression, excessive fibrin accumulation over time, and delayed remyelination. Mutant mice also present impaired macrophage recruitment and defective nerve conduction velocity (NCV). Thus, ADAM17 expressed in Schwann cells, controls the whole WD process, and its absence hampers effective nerve repair. Collectively, we describe a previously uncharacterized role for glial ADAM17 during nerve regeneration. Based on the results of our study, we posit that, unlike development, glial ADAM17 promotes remyelination through the regulation of p75NTR-mediated fibrinolysis.SIGNIFICANCE STATEMENT The α-secretase a-disintegrin and metalloproteinase (ADAM)17, although relevant for developmental PNS myelination, has never been investigated in Wallerian degeneration (WD). We now unravel a new mechanism of action for this protease and show that ADAM17 cleaves p75NTR, regulates fibrin clearance, and eventually fine-tunes remyelination. The results presented in this study provide important insights into the complex regulation of remyelination following nerve injury, identifying in ADAM17 and p75NTR a new signaling axis implicated in these events. Modulation of this pathway could have important implications in promoting nerve remyelination, an often-inefficient process, with the aim of restoring a functional axo-glial unit.
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Affiliation(s)
- Marta Pellegatta
- Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Research Hospital, Milan 20132, Italy
| | - Paolo Canevazzi
- Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Research Hospital, Milan 20132, Italy
| | - Maria Grazia Forese
- Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Research Hospital, Milan 20132, Italy
| | - Paola Podini
- Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Research Hospital, Milan 20132, Italy
| | - Serena Valenzano
- Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Research Hospital, Milan 20132, Italy
| | - Ubaldo Del Carro
- Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Research Hospital, Milan 20132, Italy
| | - Angelo Quattrini
- Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Research Hospital, Milan 20132, Italy
| | - Carla Taveggia
- Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Research Hospital, Milan 20132, Italy
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9
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Fading memories in aging and neurodegeneration: Is p75 neurotrophin receptor a culprit? Ageing Res Rev 2022; 75:101567. [PMID: 35051645 DOI: 10.1016/j.arr.2022.101567] [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: 09/14/2021] [Revised: 12/12/2021] [Accepted: 01/12/2022] [Indexed: 11/22/2022]
Abstract
Aging and age-related neurodegenerative diseases have become one of the major concerns in modern times as cognitive abilities tend to decline when we get older. It is well known that the main cause of this age-related cognitive deficit is due to aberrant changes in cellular, molecular circuitry and signaling pathways underlying synaptic plasticity and neuronal connections. The p75 neurotrophin receptor (p75NTR) is one of the important mediators regulating the fate of the neurons in the nervous system. Its importance in neuronal apoptosis is well documented. However, the mechanisms involving the regulation of p75NTR in synaptic plasticity and cognitive function remain obscure, although cognitive impairment has been associated with a higher expression of p75NTR in neurons. In this review, we discuss the current understanding of how neurons are influenced by p75NTR function to maintain normal neuronal synaptic strength and connectivity, particularly to support learning and memory in the hippocampus. We then discuss the age-associated alterations in neurophysiological mechanisms of synaptic plasticity and cognitive function. Furthermore, we also describe current evidence that has begun to elucidate how p75NTR regulates synaptic changes in aging and age-related neurodegenerative diseases, focusing on the hippocampus. Elucidating the role that p75NTR signaling plays in regulating synaptic plasticity will contribute to a better understanding of cognitive processes and pathological conditions. This will in turn provide novel approaches to improve therapies for the treatment of neurological diseases in which p75NTR dysfunction has been demonstrated.
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10
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Kulkarni K, Minehan RL, Gamot T, Coleman HA, Bowles S, Lin Q, Hopper D, Northfield SE, Hughes RA, Widdop RE, Aguilar MI, Parkington HC, Del Borgo MP. Esterase-Mediated Sustained Release of Peptide-Based Therapeutics from a Self-Assembled Injectable Hydrogel. ACS APPLIED MATERIALS & INTERFACES 2021; 13:58279-58290. [PMID: 34756031 DOI: 10.1021/acsami.1c14150] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
A synthetic strategy for conjugating small molecules and peptide-based therapeutics, via a cleavable ester bond, to a lipidated β3-tripeptide is presented. The drug-loaded β3-peptide was successfully co-assembled with a functionally inert lipidated β3-tripeptide to form a hydrogel. Quantitative release of lactose from the hydrogel, by the action of serum esterases, is demonstrated over 28 days. The esterase-mediated sustained release of the bioactive brain-derived neurotrophic factor (BDNF) peptide mimics from the hydrogel resulted in increased neuronal survival and normal neuronal function of peripheral neurons. These studies define a versatile strategy for the facile synthesis and co-assembly of self-assembling β3-peptide-based hydrogels with the ability to control drug release using endogenous esterases with potential in vivo applications for sustained localized drug delivery.
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Affiliation(s)
- Ketav Kulkarni
- Department of Biochemistry & Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Rachel L Minehan
- Department of Pharmacology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Tanesh Gamot
- Department of Mechanical and Aerospace Engineering, Monash University, Clayton, Victoria 3800, Australia
| | - Harold A Coleman
- Department of Physiology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Simon Bowles
- Department of Pharmacology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Qingqing Lin
- Department of Biochemistry & Pharmacology, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Denham Hopper
- Department of Biochemistry & Pharmacology, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Susan E Northfield
- Department of Biochemistry & Pharmacology, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Richard A Hughes
- Pharmacy and Pharmaceutical Sciences Education, Faculty of Pharmacy and Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Robert E Widdop
- Department of Pharmacology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Marie-Isabel Aguilar
- Department of Biochemistry & Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Helena C Parkington
- Department of Physiology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Mark P Del Borgo
- Department of Pharmacology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
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11
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Balakrishnan A, Belfiore L, Chu TH, Fleming T, Midha R, Biernaskie J, Schuurmans C. Insights Into the Role and Potential of Schwann Cells for Peripheral Nerve Repair From Studies of Development and Injury. Front Mol Neurosci 2021; 13:608442. [PMID: 33568974 PMCID: PMC7868393 DOI: 10.3389/fnmol.2020.608442] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Accepted: 12/31/2020] [Indexed: 12/13/2022] Open
Abstract
Peripheral nerve injuries arising from trauma or disease can lead to sensory and motor deficits and neuropathic pain. Despite the purported ability of the peripheral nerve to self-repair, lifelong disability is common. New molecular and cellular insights have begun to reveal why the peripheral nerve has limited repair capacity. The peripheral nerve is primarily comprised of axons and Schwann cells, the supporting glial cells that produce myelin to facilitate the rapid conduction of electrical impulses. Schwann cells are required for successful nerve regeneration; they partially “de-differentiate” in response to injury, re-initiating the expression of developmental genes that support nerve repair. However, Schwann cell dysfunction, which occurs in chronic nerve injury, disease, and aging, limits their capacity to support endogenous repair, worsening patient outcomes. Cell replacement-based therapeutic approaches using exogenous Schwann cells could be curative, but not all Schwann cells have a “repair” phenotype, defined as the ability to promote axonal growth, maintain a proliferative phenotype, and remyelinate axons. Two cell replacement strategies are being championed for peripheral nerve repair: prospective isolation of “repair” Schwann cells for autologous cell transplants, which is hampered by supply challenges, and directed differentiation of pluripotent stem cells or lineage conversion of accessible somatic cells to induced Schwann cells, with the potential of “unlimited” supply. All approaches require a solid understanding of the molecular mechanisms guiding Schwann cell development and the repair phenotype, which we review herein. Together these studies provide essential context for current efforts to design glial cell-based therapies for peripheral nerve regeneration.
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Affiliation(s)
- Anjali Balakrishnan
- Biological Sciences Platform, Sunnybrook Research Institute (SRI), Toronto, ON, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Lauren Belfiore
- Biological Sciences Platform, Sunnybrook Research Institute (SRI), Toronto, ON, Canada.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Tak-Ho Chu
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Taylor Fleming
- Biological Sciences Platform, Sunnybrook Research Institute (SRI), Toronto, ON, Canada
| | - Rajiv Midha
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Jeff Biernaskie
- Department of Comparative Biology and Experimental Medicine, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Carol Schuurmans
- Biological Sciences Platform, Sunnybrook Research Institute (SRI), Toronto, ON, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON, Canada.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
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12
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Qin Z, Gonsalvez DG, Wood RJ, Daemi F, Yoo S, Ivanusic JJ, Coulson EJ, Murray SS, Xiao J. Partial deletion of p75 NTR in large-diameter DRG neurons exerts no influence upon the survival of peripheral sensory neurons in vivo. J Neurosci Res 2020; 98:1987-1998. [PMID: 32585763 DOI: 10.1002/jnr.24665] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 04/20/2020] [Accepted: 05/14/2020] [Indexed: 01/19/2023]
Abstract
The p75 neurotrophin receptor (p75NTR ) is required for maintaining peripheral sensory neuron survival and function; however, the underlying cellular mechanism remains unclear. The general view is that expression of p75NTR by the neuron itself is required for maintaining sensory neuron survival and myelination in the peripheral nervous system (PNS). Adopting a neuronal-specific conditional knockout strategy, we demonstrate the partial depletion of p75NTR in neurons exerts little influence upon maintaining sensory neuron survival and peripheral nerve myelination in health and after demyelinating neuropathy. Our data show that the density and total number of dorsal root ganglion (DRG) neurons in 2-month-old mice is not affected following the deletion of p75NTR in large-diameter myelinating neurons, as assessed by stereology. Adopting experimental autoimmune neuritis induced in adult male mice, an animal model of demyelinating peripheral neuropathy, we identify that deleting p75NTR in myelinating neurons exerts no influence upon the disease progression, the total number of DRG neurons, and the extent of myelin damage in the sciatic nerve, indicating that the expression of neuronal p75NTR is not essential for maintaining peripheral neuron survival and myelination after a demyelinating insult in vivo. Together, results of this study suggest that the survival and myelination of peripheral sensory neurons is independent of p75NTR expressed by a subtype of neurons in vivo. Thus, our findings provide new insights into the mechanism underpinning p75NTR -mediated neuronal survival in the PNS.
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Affiliation(s)
- Zuoheng Qin
- Department of Anatomy and Neuroscience, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia
| | - David G Gonsalvez
- Department of Anatomy and Neuroscience, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Rhiannon J Wood
- Department of Anatomy and Neuroscience, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Fatemeh Daemi
- Department of Anatomy and Neuroscience, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Sangwon Yoo
- Department of Anatomy and Neuroscience, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Jason J Ivanusic
- Department of Anatomy and Neuroscience, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Elizabeth J Coulson
- School of Biomedical Sciences, Queensland University, Brisbane, QLD, Australia
| | - Simon S Murray
- Department of Anatomy and Neuroscience, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia
| | - Junhua Xiao
- Department of Anatomy and Neuroscience, School of Biomedical Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia
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13
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Xie Y, Seawell J, Boesch E, Allen L, Suchy A, Longo FM, Meeker RB. Small molecule modulation of the p75 neurotrophin receptor suppresses age- and genotype-associated neurodegeneration in HIV gp120 transgenic mice. Exp Neurol 2020; 335:113489. [PMID: 33007293 DOI: 10.1016/j.expneurol.2020.113489] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 09/07/2020] [Accepted: 09/28/2020] [Indexed: 12/21/2022]
Abstract
The persistence of HIV in the central nervous system leads to cognitive deficits in up to 50% of people living with HIV even with systemic suppression by antiretroviral treatment. The interaction of chronic inflammation with age-associated degeneration places these individuals at increased risk of accelerated aging and other neurodegenerative diseases and no treatments are available that effectively halt these processes. The adverse effects of aging and inflammation may be mediated, in part, by an increase in the expression of the p75 neurotrophin receptor (p75NTR) which shifts the balance of neurotrophin signaling toward less protective pathways. To determine if modulation of p75NTR could modify the disease process, we treated HIV gp120 transgenic mice with a small molecule ligand designed to engage p75NTR and downregulate degenerative signaling. Daily treatment with 50 mg/kg LM11A-31 for 4 months suppressed age- and genotype-dependent activation of microglia, increased microtubule associated protein-2 (MAP-2), reduced dendritic varicosities and slowed the loss of parvalbumin immunoreactive neurons in the hippocampus. An age related accumulation of microtubule associated protein Tau was identified in the hippocampus in extracellular clusters that co-expressed p75NTR suggesting a link between Tau and p75NTR. Although the significance of the relationship between p75NTR and Tau is unclear, a decrease in Tau-1 immunoreactivity as gp120 mice entered old age (>16 months) suggests that the Tau may transition to more pathological modifications; a process blocked by LM11A-31. Overall, the effects of LM11A-31 are consistent with strong neuroprotective and anti-inflammatory actions that have significant therapeutic potential.
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Affiliation(s)
- Youmie Xie
- Department of Neurology, University of North Carolina, Chapel Hill, NC 27599, United States of America
| | - Jaimie Seawell
- Department of Neurology, University of North Carolina, Chapel Hill, NC 27599, United States of America; The Edward Via College of Osteopathic Medicine, Spartanburg, SC 29303, United States of America
| | - Emily Boesch
- School of Pharmacy, University of North Carolina, Chapel Hill, NC 27599, United States of America
| | - Lauren Allen
- Department of Neurology, University of North Carolina, Chapel Hill, NC 27599, United States of America
| | - Ashley Suchy
- Department of Neurology, University of North Carolina, Chapel Hill, NC 27599, United States of America
| | - Frank M Longo
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA 94305, United States of America
| | - Rick B Meeker
- Department of Neurology, University of North Carolina, Chapel Hill, NC 27599, United States of America; Neurobiology Curriculum, University of North Carolina, Chapel Hill, NC 27599, United States of America.
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14
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Stassart RM, Woodhoo A. Axo-glial interaction in the injured PNS. Dev Neurobiol 2020; 81:490-506. [PMID: 32628805 DOI: 10.1002/dneu.22771] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/28/2020] [Accepted: 06/12/2020] [Indexed: 12/11/2022]
Abstract
Axons share a close relationship with Schwann cells, their glial partners in peripheral nerves. An intricate axo-glia network of signals and bioactive molecules regulates the major aspects of nerve development and normal functioning of the peripheral nervous system. Disruptions to these complex axo-glial interactions can have serious neurological consequences, as typically seen in injured nerves. Recent studies in inherited neuropathies have demonstrated that damage to one of the partners in this symbiotic unit ultimately leads to impairment of the other partner, emphasizing the bidirectional influence of axon to glia and glia to axon signaling in these diseases. After physical trauma to nerves, dramatic alterations in the architecture and signaling environment of peripheral nerves take place. Here, axons and Schwann cells respond adaptively to these perturbations and change the nature of their reciprocal interactions, thereby driving the remodeling and regeneration of peripheral nerves. In this review, we focus on the nature and importance of axon-glia interactions in injured nerves, both for the reshaping and repair of nerves after trauma, and in driving pathology in inherited peripheral neuropathies.
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Affiliation(s)
- Ruth M Stassart
- Department of Neuropathology, University Clinic Leipzig, Leipzig, Germany
| | - Ashwin Woodhoo
- Nerve Disorders Laboratory, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia, Spain.,IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
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15
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Chen J, Chen YQ, Wang SN, Duan FX, Shi YJ, Ding SQ, Hu JG, Lü HZ. Effect of VX‑765 on the transcriptome profile of mice spinal cords with acute injury. Mol Med Rep 2020; 22:33-42. [PMID: 32377730 PMCID: PMC7248530 DOI: 10.3892/mmr.2020.11129] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 11/18/2019] [Indexed: 12/12/2022] Open
Abstract
Previous studies have shown that caspase-1 plays an important role in the acute inflammatory response of spinal cord injury (SCI). VX‑765, a novel and irreversible caspase‑1 inhibitor, has been reported to effectively intervene in inflammation. However, the effect of VX‑765 on genome‑wide transcription in acutely injured spinal cords remains unknown. Therefore, in the present study, RNA‑sequencing (RNA‑Seq) was used to analyze the effect of VX‑765 on the local expression of gene transcription 8 h following injury. The differentially expressed genes (DEGs) underwent enrichment analysis of functions and pathways by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses, respectively. Parallel analysis of western blot confirmed that VX‑765 can effectively inhibit the expression and activation of caspase‑1. RNA‑Seq showed that VX‑765 treatment resulted in 1,137 upregulated and 1,762 downregulated DEGs. These downregulated DEGs and their associated signaling pathways, such as focal adhesion, cytokine‑cytokine receptor interaction, leukocyte transendothelial migration, extracellular matrix‑receptor interaction, phosphatidylinositol 3‑kinase‑protein kinase B, Rap1 and hypoxia inducible factor‑1 signaling pathway, are mainly associated with inflammatory response, local hypoxia, macrophage differentiation, adhesion migration and apoptosis of local cells. This suggests that the application of VX‑765 in the acute phase can improve the local microenvironment of SCI by inhibiting caspase‑1. However, whether VX‑765 can be used as a therapeutic drug for SCI requires further exploration. The sequence data have been deposited into the Sequence Read Archive (https://www.ncbi.nlm.nih.gov/sra/PRJNA548970).
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Affiliation(s)
- Jing Chen
- Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui 233004, P.R. China
| | - Yu-Qing Chen
- Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui 233004, P.R. China
| | - Sai-Nan Wang
- Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui 233004, P.R. China
| | - Fei-Xiang Duan
- Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui 233004, P.R. China
| | - Yu-Jiao Shi
- Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui 233004, P.R. China
| | - Shu-Qin Ding
- Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui 233004, P.R. China
| | - Jian-Guo Hu
- Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui 233004, P.R. China
| | - He-Zuo Lü
- Clinical Laboratory, The First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui 233004, P.R. China
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16
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Wilson ER, Della-Flora Nunes G, Weaver MR, Frick LR, Feltri ML. Schwann cell interactions during the development of the peripheral nervous system. Dev Neurobiol 2020; 81:464-489. [PMID: 32281247 DOI: 10.1002/dneu.22744] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 03/14/2020] [Accepted: 04/06/2020] [Indexed: 12/21/2022]
Abstract
Schwann cells play a critical role in the development of the peripheral nervous system (PNS), establishing important relationships both with the extracellular milieu and other cell types, particularly neurons. In this review, we discuss various Schwann cell interactions integral to the proper establishment, spatial arrangement, and function of the PNS. We include signals that cascade onto Schwann cells from axons and from the extracellular matrix, bidirectional signals that help to establish the axo-glial relationship and how Schwann cells in turn support the axon. Further, we speculate on how Schwann cell interactions with other components of the developing PNS ultimately promote the complete construction of the peripheral nerve.
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Affiliation(s)
- Emma R Wilson
- Hunter James Kelly Research Institute, State University of New York at Buffalo, Buffalo, NY, USA.,Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA
| | - Gustavo Della-Flora Nunes
- Hunter James Kelly Research Institute, State University of New York at Buffalo, Buffalo, NY, USA.,Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA
| | - Michael R Weaver
- Hunter James Kelly Research Institute, State University of New York at Buffalo, Buffalo, NY, USA.,Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA
| | - Luciana R Frick
- Hunter James Kelly Research Institute, State University of New York at Buffalo, Buffalo, NY, USA.,Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA
| | - M Laura Feltri
- Hunter James Kelly Research Institute, State University of New York at Buffalo, Buffalo, NY, USA.,Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA.,Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA
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17
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Gonçalves NP, Mohseni S, El Soury M, Ulrichsen M, Richner M, Xiao J, Wood RJ, Andersen OM, Coulson EJ, Raimondo S, Murray SS, Vægter CB. Peripheral Nerve Regeneration Is Independent From Schwann Cell p75 NTR Expression. Front Cell Neurosci 2019; 13:235. [PMID: 31191256 PMCID: PMC6548843 DOI: 10.3389/fncel.2019.00235] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 05/09/2019] [Indexed: 01/27/2023] Open
Abstract
Schwann cell reprogramming and differentiation are crucial prerequisites for neuronal regeneration and re-myelination to occur following injury to peripheral nerves. The neurotrophin receptor p75NTR has been identified as a positive modulator for Schwann cell myelination during development and implicated in promoting nerve regeneration after injury. However, most studies base this conclusion on results obtained from complete p75NTR knockout mouse models and cannot dissect the specific role of p75NTR expressed by Schwann cells. In this present study, a conditional knockout model selectively deleting p75NTR expression in Schwann cells was generated, where p75NTR expression is replaced with that of an mCherry reporter. Silencing of Schwann cell p75NTR expression was confirmed in the sciatic nerve in vivo and in vitro, without altering axonal expression of p75NTR. No difference in sciatic nerve myelination during development or following sciatic nerve crush injury was observed, as determined by quantification of both myelinated and unmyelinated nerve fiber densities, myelinated axonal diameter and myelin thickness. However, the absence of Schwann cell p75NTR reduced motor nerve conduction velocity after crush injury. Our data indicate that the absence of Schwann cell p75NTR expression in vivo is not critical for axonal regrowth or remyelination following sciatic nerve crush injury, but does play a key role in functional recovery. Overall, this represents the first step in redefining the role of p75NTR in the peripheral nervous system, suggesting that the Schwann cell-axon unit functions as a syncytium, with the previous published involvement of p75NTR in remyelination most likely depending on axonal/neuronal p75NTR and/or mutual glial-axonal interactions.
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Affiliation(s)
- Nádia P. Gonçalves
- Danish Research Institute of Translational Neuroscience – DANDRITE, Nordic-EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, Aarhus, Denmark
- The International Diabetic Neuropathy Consortium, Aarhus University Hospital, Aarhus, Denmark
| | - Simin Mohseni
- Division of Cell Biology, Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Marwa El Soury
- Department of Clinical and Biological Sciences, Neuroscience Institute Cavalieri Ottolenghi, University of Turin, Turin, Italy
| | - Maj Ulrichsen
- Danish Research Institute of Translational Neuroscience – DANDRITE, Nordic-EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Mette Richner
- Danish Research Institute of Translational Neuroscience – DANDRITE, Nordic-EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Junhua Xiao
- Department of Anatomy and Neuroscience, School of Biomedical Science, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, VIC, Australia
| | - Rhiannon J. Wood
- Department of Anatomy and Neuroscience, School of Biomedical Science, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, VIC, Australia
| | - Olav M. Andersen
- Danish Research Institute of Translational Neuroscience – DANDRITE, Nordic-EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Elizabeth J. Coulson
- School of Biomedical Sciences, Faculty of Medicine, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
| | - Stefania Raimondo
- Department of Anatomy and Neuroscience, School of Biomedical Science, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, VIC, Australia
| | - Simon S. Murray
- Department of Anatomy and Neuroscience, School of Biomedical Science, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Parkville, VIC, Australia
| | - Christian B. Vægter
- Danish Research Institute of Translational Neuroscience – DANDRITE, Nordic-EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, Aarhus, Denmark
- The International Diabetic Neuropathy Consortium, Aarhus University Hospital, Aarhus, Denmark
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18
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Pellegatta M, Taveggia C. The Complex Work of Proteases and Secretases in Wallerian Degeneration: Beyond Neuregulin-1. Front Cell Neurosci 2019; 13:93. [PMID: 30949030 PMCID: PMC6436609 DOI: 10.3389/fncel.2019.00093] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 02/26/2019] [Indexed: 01/24/2023] Open
Abstract
After damage, axons in the peripheral nervous system (PNS) regenerate and regrow following a process termed Wallerian degeneration, but the regenerative process is often incomplete and usually the system does not reach full recovery. Key steps to the creation of a permissive environment for axonal regrowth are the trans-differentiation of Schwann cells and the remodeling of the extracellular matrix (ECM). In this review article, we will discuss how proteases and secretases promote effective regeneration and remyelination. We will detail how they control neuregulin-1 (NRG-1) activity at the post-translational level, as the concerted action of alpha, beta and gamma secretases cooperates to balance activating and inhibitory signals necessary for physiological myelination and remyelination. In addition, we will discuss the role of other proteases in nerve repair, among which A Disintegrin And Metalloproteinases (ADAMs) and gamma-secretases substrates. Moreover, we will present how matrix metalloproteinases (MMPs) and proteases of the blood coagulation cascade participate in forming newly synthetized myelin and in regulating axonal regeneration. Overall, we will highlight how a deeper comprehension of secretases and proteases mechanism of action in Wallerian degeneration might be useful to develop new therapies with the potential of readily and efficiently improve the regenerative process.
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Affiliation(s)
- Marta Pellegatta
- Division of Neuroscience and INSPE at IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Carla Taveggia
- Division of Neuroscience and INSPE at IRCCS San Raffaele Scientific Institute, Milan, Italy
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19
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McGregor CE, English AW. The Role of BDNF in Peripheral Nerve Regeneration: Activity-Dependent Treatments and Val66Met. Front Cell Neurosci 2019; 12:522. [PMID: 30687012 PMCID: PMC6336700 DOI: 10.3389/fncel.2018.00522] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 12/14/2018] [Indexed: 11/29/2022] Open
Abstract
Despite the ability of peripheral nerves to spontaneously regenerate after injury, recovery is generally very poor. The neurotrophins have emerged as an important modulator of axon regeneration, particularly brain derived neurotrophic factor (BDNF). BDNF regulation and signaling, as well as its role in activity-dependent treatments including electrical stimulation, exercise, and optogenetic stimulation are discussed here. The importance of a single nucleotide polymorphism in the BDNF gene, Val66Met, which is present in 30% of the human population and may hinder the efficacy of these treatments in enhancing regeneration after injury is considered. Preliminary data are presented on the effectiveness of one such activity-dependent treatment, electrical stimulation, in enhancing axon regeneration in mice expressing the met allele of the Val66Met polymorphism.
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Affiliation(s)
- Claire Emma McGregor
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, United States
| | - Arthur W English
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, United States
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20
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Becker K, Cana A, Baumgärtner W, Spitzbarth I. p75 Neurotrophin Receptor: A Double-Edged Sword in Pathology and Regeneration of the Central Nervous System. Vet Pathol 2018; 55:786-801. [PMID: 29940812 DOI: 10.1177/0300985818781930] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The low-affinity nerve growth factor receptor p75NTR is a major neurotrophin receptor involved in manifold and pleiotropic functions in the developing and adult central nervous system (CNS). Although known for decades, its entire functions are far from being fully elucidated. Depending on the complex interactions with other receptors and on the cellular context, p75NTR is capable of performing contradictory tasks such as mediating cell death as well as cell survival. In parallel, as a prototype marker for certain differentiation stages of Schwann cells and related CNS aldynoglial cells, p75NTR has recently gained increasing notice as a marker for cells with proposed regenerative potential in CNS diseases, such as demyelinating disease and traumatic CNS injury. Besides its pivotal role as a marker for transplantation candidate cells, recent studies in canine neuroinflammatory CNS conditions also highlight a spontaneous endogenous occurrence of p75NTR-positive glia, which potentially play a role in Schwann cell-mediated CNS remyelination. The aim of the present communication is to review the pleiotropic functions of p75NTR in the CNS with a special emphasis on its role as an immunohistochemical marker in neuropathology. Following a brief illustration of the expression of p75NTR in neurogenesis and in developed neuronal populations, the implications of p75NTR expression in astrocytes, oligodendrocytes, and microglia are addressed. A special focus is put on the role of p75NTR as a cell marker for specific differentiation stages of Schwann cells and a regeneration-promoting CNS population, collectively referred to as aldynoglia.
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Affiliation(s)
- Kathrin Becker
- 1 Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Armend Cana
- 1 Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany.,2 Center for Systems Neuroscience, Hannover, Germany
| | - Wolfgang Baumgärtner
- 1 Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany.,2 Center for Systems Neuroscience, Hannover, Germany
| | - Ingo Spitzbarth
- 1 Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany.,2 Center for Systems Neuroscience, Hannover, Germany
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21
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Kohn-Polster C, Bhatnagar D, Woloszyn DJ, Richtmyer M, Starke A, Springwald AH, Franz S, Schulz-Siegmund M, Kaplan HM, Kohn J, Hacker MC. Dual-Component Gelatinous Peptide/Reactive Oligomer Formulations as Conduit Material and Luminal Filler for Peripheral Nerve Regeneration. Int J Mol Sci 2017; 18:E1104. [PMID: 28531139 PMCID: PMC5455012 DOI: 10.3390/ijms18051104] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 05/09/2017] [Accepted: 05/17/2017] [Indexed: 02/01/2023] Open
Abstract
Toward the next generation of nerve guidance conduits (NGCs), novel biomaterials and functionalization concepts are required to address clinical demands in peripheral nerve regeneration (PNR). As a biological polymer with bioactive motifs, gelatinous peptides are promising building blocks. In combination with an anhydride-containing oligomer, a dual-component hydrogel system (cGEL) was established. First, hollow cGEL tubes were fabricated by a continuous dosing and templating process. Conduits were characterized concerning their mechanical strength, in vitro and in vivo degradation and biocompatibility. Second, cGEL was reformulated as injectable shear thinning filler for established NGCs, here tyrosine-derived polycarbonate-based braided conduits. Thereby, the formulation contained the small molecule LM11A-31. The biofunctionalized cGEL filler was assessed regarding building block integration, mechanical properties, in vitro cytotoxicity, and growth permissive effects on human adipose tissue-derived stem cells. A positive in vitro evaluation motivated further application of the filler material in a sciatic nerve defect. Compared to the empty conduit and pristine cGEL, the functionalization performed superior, though the autologous nerve graft remains the gold standard. In conclusion, LM11A-31 functionalized cGEL filler with extracellular matrix (ECM)-like characteristics and specific biochemical cues holds great potential to support PNR.
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Affiliation(s)
- Caroline Kohn-Polster
- Institute of Pharmacy, Pharmaceutical Technology, Leipzig University, 04317 Leipzig, Germany.
- Collaborative Research Center (SFB-TR67), Matrixengineering Leipzig and Dresden, Germany.
| | - Divya Bhatnagar
- New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, NJ 08854-8066, USA.
| | - Derek J Woloszyn
- New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, NJ 08854-8066, USA.
- Boston University School of Medicine, Boston University, Boston, MA 02118, USA.
| | - Matthew Richtmyer
- New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, NJ 08854-8066, USA.
| | - Annett Starke
- Institute of Pharmacy, Pharmaceutical Technology, Leipzig University, 04317 Leipzig, Germany.
| | - Alexandra H Springwald
- Institute of Pharmacy, Pharmaceutical Technology, Leipzig University, 04317 Leipzig, Germany.
| | - Sandra Franz
- Collaborative Research Center (SFB-TR67), Matrixengineering Leipzig and Dresden, Germany.
- Department of Dermatology, Venereology and Allergology of Medical Faculty of Leipzig University, 04317 Leipzig, Germany.
| | - Michaela Schulz-Siegmund
- Institute of Pharmacy, Pharmaceutical Technology, Leipzig University, 04317 Leipzig, Germany.
- Collaborative Research Center (SFB-TR67), Matrixengineering Leipzig and Dresden, Germany.
| | - Hilton M Kaplan
- New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, NJ 08854-8066, USA.
| | - Joachim Kohn
- New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, NJ 08854-8066, USA.
| | - Michael C Hacker
- Institute of Pharmacy, Pharmaceutical Technology, Leipzig University, 04317 Leipzig, Germany.
- Collaborative Research Center (SFB-TR67), Matrixengineering Leipzig and Dresden, Germany.
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Gamage KK, Cheng I, Park RE, Karim MS, Edamura K, Hughes C, Spano AJ, Erisir A, Deppmann CD. Death Receptor 6 Promotes Wallerian Degeneration in Peripheral Axons. Curr Biol 2017; 27:890-896. [PMID: 28285993 DOI: 10.1016/j.cub.2017.01.062] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 12/19/2016] [Accepted: 01/30/2017] [Indexed: 11/17/2022]
Abstract
Axon degeneration during development is required to sculpt a functional nervous system and is also a hallmark of pathological insult, such as injury [1, 2]. Despite similar morphological characteristics, very little overlap in molecular mechanisms has been reported between pathological and developmental degeneration [3-5]. In the peripheral nervous system (PNS), developmental axon pruning relies on receptor-mediated extrinsic degeneration mechanisms to determine which axons are maintained or degenerated [5-7]. Receptors have not been implicated in Wallerian axon degeneration; instead, axon autonomous, intrinsic mechanisms are thought to be the primary driver for this type of axon disintegration [8-10]. Here we survey the role of neuronally expressed, paralogous tumor necrosis factor receptor super family (TNFRSF) members in Wallerian degeneration. We find that an orphan receptor, death receptor 6 (DR6), is required to drive axon degeneration after axotomy in sympathetic and sensory neurons cultured in microfluidic devices. We sought to validate these in vitro findings in vivo using a transected sciatic nerve model. Consistent with the in vitro findings, DR6-/- animals displayed preserved axons up to 4 weeks after injury. In contrast to phenotypes observed in Wlds and Sarm1-/- mice, preserved axons in DR6-/- animals display profound myelin remodeling. This indicates that deterioration of axons and myelin after axotomy are mechanistically distinct processes. Finally, we find that JNK signaling after injury requires DR6, suggesting a link between this novel extrinsic pathway and the axon autonomous, intrinsic pathways that have become established for Wallerian degeneration.
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Affiliation(s)
- Kanchana K Gamage
- Department of Biology, University of Virginia, Charlottesville, VA 22903, USA
| | - Irene Cheng
- Department of Biology, University of Virginia, Charlottesville, VA 22903, USA; Neuroscience Graduate Program, University of Virginia, Charlottesville, VA 22903, USA
| | - Rachel E Park
- Department of Biology, University of Virginia, Charlottesville, VA 22903, USA
| | - Mardeen S Karim
- Department of Biology, University of Virginia, Charlottesville, VA 22903, USA
| | - Kazusa Edamura
- Department of Biology, University of Virginia, Charlottesville, VA 22903, USA
| | - Christopher Hughes
- Department of Physics and Astronomy, James Madison University, Harrisonburg, VA 22807, USA
| | - Anthony J Spano
- Department of Biology, University of Virginia, Charlottesville, VA 22903, USA
| | - Alev Erisir
- Department of Psychology, University of Virginia, Charlottesville, VA 22903, USA
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Ma KH, Hung HA, Svaren J. Epigenomic Regulation of Schwann Cell Reprogramming in Peripheral Nerve Injury. J Neurosci 2016; 36:9135-47. [PMID: 27581455 PMCID: PMC5005723 DOI: 10.1523/jneurosci.1370-16.2016] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 07/08/2016] [Accepted: 07/15/2016] [Indexed: 12/16/2022] Open
Abstract
UNLABELLED The rapid and dynamic transcriptional changes of Schwann cells in response to injury are critical to peripheral nerve repair, yet the epigenomic reprograming that leads to the induction of injury-activated genes has not been characterized. Polycomb Repressive Complex 2 (PRC2) catalyzes the trimethylation of lysine 27 of histone H3 (H3K27me3), which produces a transcriptionally repressive chromatin environment. We find that many promoters and/or gene bodies of injury-activated genes of mature rat nerves are occupied with H3K27me3. In contrast, the majority of distal enhancers that gain H3K27 acetylation after injury are not repressed by H3K27 methylation before injury, which is normally observed in developmentally poised enhancers. Injury induces demethylation of H3K27 in many genes, such as Sonic hedgehog (Shh), which is silenced throughout Schwann cell development before injury. In addition, experiments using a Schwann cell-specific mouse knock-out of the Eed subunit of PRC2 indicate that demethylation is a rate-limiting step in the activation of such genes. We also show that some transcription start sites of H3K27me3-repressed injury genes of uninjured nerves are bound with a mark of active promoters H3K4me3, for example, Shh and Gdnf, and the reduction of H3K27me3 results in increased trimethylation of H3K4. Our findings identify reversal of polycomb repression as a key step in gene activation after injury. SIGNIFICANCE STATEMENT Peripheral nerve regeneration after injury is dependent upon implementation of a novel genetic program in Schwann cells that supports axonal survival and regeneration. Identifying means to enhance Schwann cell reprogramming after nerve injury could be used to foster effective remyelination in the treatment of demyelinating disorders and in identifying pathways involved in regenerative process of myelination. Although recent progress has identified transcriptional determinants of successful reprogramming of the Schwann cell transcriptome after nerve injury, our results have highlighted a novel epigenomic pathway in which reversal of the Polycomb pathway of repressive histone methylation is required for activation of a significant number of injury-induced genes.
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Affiliation(s)
- Ki H Ma
- Waisman Center, Cellular and Molecular Pathology Graduate Program, and
| | - Holly A Hung
- Waisman Center, Cellular and Molecular Pathology Graduate Program, and
| | - John Svaren
- Waisman Center, Department of Comparative Biosciences, University of Wisconsin, Madison, Wisconsin 53705
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24
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Jian C, Zou D, Luo C, Liu X, Meng L, Huang J, Li X, Huang R, Wu Y. Cognitive deficits are ameliorated by reduction in amyloid β accumulation in Tg2576/p75NTR+/− mice. Life Sci 2016; 155:167-73. [DOI: 10.1016/j.lfs.2016.05.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 04/15/2016] [Accepted: 05/06/2016] [Indexed: 10/21/2022]
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25
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Chronic mild stress influences nerve growth factor through a matrix metalloproteinase-dependent mechanism. Psychoneuroendocrinology 2016; 66:11-21. [PMID: 26771945 DOI: 10.1016/j.psyneuen.2015.12.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Revised: 12/02/2015] [Accepted: 12/17/2015] [Indexed: 01/19/2023]
Abstract
Stress is generally a beneficial experience that motivates an organism to action to overcome the stressful challenge. In particular situations, when stress becomes chronic might be harmful and devastating. The hypothalamus is a critical coordinator of stress and the metabolic response; therefore, disruptions in this structure may be a significant cause of the hormonal and metabolic disturbances observed in depression. Chronic stress induces adverse changes in the morphology of neural cells that are often associated with a deficiency of neurotrophic factors (NTFs); additionally, many studies indicate that insufficient NTF synthesis may participate in the pathogenesis of depression. The aim of the present study was to determine the expression of the nerve growth factor (NGF) in the hypothalamus of male rats subjected to chronic mild stress (CMS) or to prenatal stress (PS) and to PS in combination with an acute stress event (AS). It has been found that chronic mild stress, but not prenatal stress, acute stress or a combination of PS with AS, decreased the concentration of the mature form of NGF (m-NGF) in the rat hypothalamus. A discrepancy between an increase in the Ngf mRNA and a decrease in the m-NGF levels suggested that chronic mild stress inhibited NGF maturation or enhanced the degradation of this factor. We have shown that NGF degradation in the hypothalamus of rats subjected to chronic mild stress is matrix metalloproteinase-dependent and related to an increase in the active forms of some metalloproteinases (MMP), including MMP2, MMP3, MMP9 and MMP13, while the NGF maturation process does not seem to be changed. We suggested that activated MMP2 and MMP9 potently cleave the mature but not the pro- form of NGF into biologically inactive products, which is the reason for m-NGF decomposition. In turn, the enhanced expression of Ngf in the hypothalamus of these rats is an attempt to overcome the reduced levels of m-NGF. Additionally, the decreased level of m-NGF together with the increased level of pro-NGF can decrease TrkA-mediated neuronal survival signalling and enhance the action of pro-NGF on the p75(NTR) receptor, respectively, to evoke pro-apoptotic signalling. This hypothesis is supported by elevated levels of the caspase-3 mRNA in the hypothalamus of rats subjected to chronic mild stress.
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26
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Schuh CMAP, Morton TJ, Banerjee A, Grasl C, Schima H, Schmidhammer R, Redl H, Ruenzler D. Activated Schwann Cell-Like Cells on Aligned Fibrin-Poly(Lactic-Co-Glycolic Acid) Structures: A Novel Construct for Application in Peripheral Nerve Regeneration. Cells Tissues Organs 2015; 200:287-99. [PMID: 26372904 DOI: 10.1159/000437091] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/22/2015] [Indexed: 11/19/2022] Open
Abstract
Tissue engineering approaches in nerve regeneration search for ways to support gold standard therapy (autologous nerve grafts) and to improve results by bridging nerve defects with different kinds of conduits. In this study, we describe electrospinning of aligned fibrin-poly(lactic-co-glycolic acid) (PLGA) fibers in an attempt to create a biomimicking tissue-like material seeded with Schwann cell-like cells (SCLs) in vitro for potential use as an in vivo scaffold. Rat adipose-derived stem cells (rASCs) were differentiated into SCLs and evaluated with flow cytometry concerning their differentiation and activation status [S100b, P75, myelin-associated glycoprotein (MAG), and protein 0 (P0)]. After receiving the proliferation stimulus forskolin, SCLs expressed S100b and P75; comparable to native, activated Schwann cells, while cultured without forskolin, cells switched to a promyelinating phenotype and expressed S100b, MAG, and P0. Human fibrinogen and thrombin, blended with PLGA, were electrospun and the alignment and homogeneity of the fibers were proven by scanning electron microscopy. Electrospun scaffolds were seeded with SCLs and the formation of Büngner-like structures in SCLs was evaluated with phalloidin/propidium iodide staining. Carrier fibrin gels containing rASCs acted as a self-shaping matrix to form a tubular structure. In this study, we could show that rASCs can be differentiated into activated, proliferating SCLs and that these cells react to minimal changes in stimulus, switching to a promyelinating phenotype. Aligned electrospun fibrin-PLGA fibers promoted the formation of Büngner-like structures in SCLs, which also rolled the fibrin-PLGA matrix into a tubular scaffold. These in vitro findings favor further in vivo testing.
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Affiliation(s)
- Christina M A P Schuh
- Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA Research Center, Vienna, Austria
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27
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Meeker RB, Williams KS. The p75 neurotrophin receptor: at the crossroad of neural repair and death. Neural Regen Res 2015; 10:721-5. [PMID: 26109945 PMCID: PMC4468762 DOI: 10.4103/1673-5374.156967] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/07/2015] [Indexed: 12/14/2022] Open
Abstract
The strong repair and pro-survival functions of neurotrophins at their primary receptors, TrkA, TrkB and TrkC, have made them attractive candidates for treatment of nervous system injury and disease. However, difficulties with the clinical implementation of neurotrophin therapies have prompted the search for treatments that are stable, easier to deliver and allow more precise regulation of neurotrophin actions. Recently, the p75 neurotrophin receptor (p75NTR) has emerged as a potential target for pharmacological control of neurotrophin activity, supported in part by studies demonstrating 1) regulation of neural plasticity in the mature nervous system, 2) promotion of adult neurogenesis and 3) increased expression in neurons, macrophages, microglia, astrocytes and/or Schwann cells in response to injury and neurodegenerative diseases. Although the receptor has no intrinsic catalytic activity it interacts with and modulates the function of TrkA, TrkB, and TrkC, as well as sortilin and the Nogo receptor. This provides substantial cellular and molecular diversity for regulation of neuron survival, neurogenesis, immune responses and processes that support neural function. Upregulation of the p75NTR under pathological conditions places the receptor in a key position to control numerous processes necessary for nervous system recovery. Support for this possibility has come from recent studies showing that small, non-peptide p75NTR ligands can selectively modify pro-survival and repair functions. While a great deal remains to be discovered about the wide ranging functions of the p75NTR, studies summarized in this review highlight the immense potential for development of novel neuroprotective and neurorestorative therapies.
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Affiliation(s)
- Rick B Meeker
- Department of Neurology, University of North Carolina, Chapel Hill, NC, USA
| | - Kimberly S Williams
- Curriculum in Neurobiology, University of North Carolina, Chapel Hill, NC, USA
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28
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Mangus LM, Dorsey JL, Laast VA, Ringkamp M, Ebenezer GJ, Hauer P, Mankowski JL. Unraveling the pathogenesis of HIV peripheral neuropathy: insights from a simian immunodeficiency virus macaque model. ILAR J 2015; 54:296-303. [PMID: 24615443 DOI: 10.1093/ilar/ilt047] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Peripheral neuropathy (PN) is the most frequent neurologic complication in individuals infected with human immunodeficiency virus (HIV). It affects over one third of infected patients, including those receiving effective combination antiretroviral therapy. The pathogenesis of HIV-associated peripheral neuropathy (HIV-PN) remains poorly understood. Clinical studies are complicated because both HIV and antiretroviral treatment cause damage to the peripheral nervous system. To study HIV-induced peripheral nervous system (PNS) damage, a unique simian immunodeficiency virus (SIV)/pigtailed macaque model of HIV-PN that enabled detailed morphologic and functional evaluation of the somatosensory pathway throughout disease progression was developed. Studies in this model have demonstrated that SIV induces key pathologic features that closely resemble HIV-induced alterations, including inflammation and damage to the neuronal cell bodies in somatosensory ganglia and decreased epidermal nerve fiber density. Insights generated in the model include: finding that SIV alters the conduction properties of small, unmyelinated peripheral nerves; and that SIV impairs peripheral nerve regeneration. This review will highlight the major findings in the SIV-infected pigtailed macaque model of HIV-PN, and will illustrate the great value of a reliable large animal model to show the pathogenesis of this complex, HIV-induced disorder of the PNS.
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29
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Friesland A, Weng Z, Duenas M, Massa SM, Longo FM, Lu Q. Amelioration of cisplatin-induced experimental peripheral neuropathy by a small molecule targeting p75 NTR. Neurotoxicology 2014; 45:81-90. [PMID: 25277379 PMCID: PMC4268328 DOI: 10.1016/j.neuro.2014.09.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 08/18/2014] [Accepted: 09/22/2014] [Indexed: 12/18/2022]
Abstract
Cisplatin is an effective and widely used first-line chemotherapeutic drug for treating cancers. However, many patients sustain cisplatin-induced peripheral neuropathy (CIPN), often leading to a reduction in drug dosages or complete cessation of treatment altogether. Therefore, it is important to understand cisplatin mechanisms in peripheral nerve tissue mediating its toxicity and identify signaling pathways for potential intervention. Rho GTPase activation is increased following trauma in several models of neuronal injury. Thus, we investigated whether components of the Rho signaling pathway represent important neuroprotective targets with the potential to ameliorate CIPN and thereby optimize current chemotherapy treatment regimens. We have developed a novel CIPN model in the mouse. Using this model and primary neuronal culture, we determined whether LM11A-31, a small-molecule, orally bioavailable ligand of the p75 neurotrophin receptor (p75(NTR)), can modulate Rho GTPase signaling and reduce CIPN. Von Frey filament analysis of sural nerve function showed that LM11A-31 treatment prevented decreases in peripheral nerve sensation seen with cisplatin treatment. Morphometric analysis of harvested sural nerves revealed that cisplatin-induced abnormal nerve fiber morphology and the decreases in fiber area were alleviated with concurrent LM11A-31 treatment. Cisplatin treatment increased RhoA activity accompanied by the reduced tyrosine phosphorylation of SHP2, which was reversed by LM11A-31. LM11A-31 also countered the effects of calpeptin, which activated RhoA by inhibiting SHP2 tyrosine phosphatase. Therefore, suppression of RhoA signaling by LM11A-31 that modulates p75(NTR) or activates SHP2 tyrosine phosphatase downstream of the NGF receptor enhances neuroprotection in experimental CIPN in mouse model.
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Affiliation(s)
- Amy Friesland
- Department of Anatomy and Cell Biology, The Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA; Leo Jenkins Cancer Center, The Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Zhiying Weng
- Department of Anatomy and Cell Biology, The Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA; School of Pharmaceutical Science and Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, Kunming 650500, China
| | - Maria Duenas
- Department of Anatomy and Cell Biology, The Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Stephen M Massa
- Department of Neurology Veterans Administration Medical Center and University of California at San Francisco, San Francisco, CA 94121, USA
| | - Frank M Longo
- Department of Neurology and Neurological Science, Stanford University, Stanford, CA 94305, USA
| | - Qun Lu
- Department of Anatomy and Cell Biology, The Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA; Leo Jenkins Cancer Center, The Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA.
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30
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Meeker R, Williams K. Dynamic nature of the p75 neurotrophin receptor in response to injury and disease. J Neuroimmune Pharmacol 2014; 9:615-28. [PMID: 25239528 DOI: 10.1007/s11481-014-9566-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 09/03/2014] [Indexed: 12/23/2022]
Abstract
Neurotrophins and their respective tropomyosin related kinase (Trk) receptors (TrkA, TrkB, and TrkC) and the p75 neurotrophin receptor (p75(NTR)) play a fundamental role in the development and maintenance of the nervous system making them important targets for treatment of neurodegenerative diseases. Whereas Trk receptors are directly activated by specific neurotrophins, the p75(NTR) is a multifunctional receptor that exerts its effects via heterodimeric interactions with TrkA, TrkB, TrkC, sortilin or the Nogo receptor to regulate a wide array of cellular functions. By partnering with different receptors the p75(NTR) regulates binding of mature versus pro-neurotrophins and activation of different signaling pathways with outcomes ranging from growth and survival to cell death. While the developmental downregulation of the p75(NTR) has raised questions regarding its role in the mature nervous system, recent data have revealed widespread expression of low levels, a role in synaptic plasticity and adult neurogenesis and upregulation in response to injury or disease. Studies are needed to better understand these processes, particularly in the damaged nervous system, but will be complicated by expression of p75(NTR) on immune cells including macrophages and microglia that are intimately involved in disease and repair processes. Recent approaches that regulate p75(NTR) function with small non-peptide ligands have demonstrated potent neuroprotection in models of injury and neurodegenerative diseases that highlight the importance of the p75(NTR) as a therapeutic target. Future studies hold the promise of revealing a wealth of information on the multifaceted actions of the p75(NTR) that will inform the design of new neurotrophin-based therapies.
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Affiliation(s)
- Rick Meeker
- Department of Neurology, University of North Carolina, CB #7025 6109F Neuroscience Research Building, 115 Mason Farm Road, Chapel Hill, NC, 27599, USA,
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31
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Ma S, Peng C, Wu S, Wu D, Gao C. Sciatic nerve regeneration using a nerve growth factor-containing fibrin glue membrane. Neural Regen Res 2014; 8:3416-22. [PMID: 25206664 PMCID: PMC4146009 DOI: 10.3969/j.issn.1673-5374.2013.36.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2013] [Accepted: 11/02/2013] [Indexed: 01/23/2023] Open
Abstract
Our previous findings confirmed that the nerve growth factor-containing fibrin glue membrane provides a good microenvironment for peripheral nerve regeneration; however, the precise mechanism remains unclear. p75 neurotrophin receptor (p75(NTR)) plays an important role in the regulation of peripheral nerve regeneration. We hypothesized that a nerve growth factor-containing fibrin glue membrane can promote neural regeneration by up-regulating p75(NTR) expression. In this study, we used a silicon nerve conduit to bridge a 15 mm-long sciatic nerve defect and injected a mixture of nerve growth factor and fibrin glue at the anastomotic site of the nerve conduit and the sciatic nerve. Through RT-PCR and western blot analysis, nerve growth factor-containing fibrin glue membrane significantly increased p75(NTR) mRNA and protein expression in the Schwann cells at the anastomotic site, in particular at 8 weeks after injection of the nerve growth factor/fibrin glue mixture. These results indicate that nerve growth factor-containing fibrin glue membrane can promote peripheral nerve regeneration by up-regulating p75(NTR) expression in Schwann cells.
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Affiliation(s)
- Shengzhong Ma
- Department of Orthopedics, Second Affiliated Hospital of Shandong University, Jinan 250033, Shandong Province, China
| | - Changliang Peng
- Department of Orthopedics, Second Affiliated Hospital of Shandong University, Jinan 250033, Shandong Province, China
| | - Shiqing Wu
- Department of Orthopedics, Second Affiliated Hospital of Shandong University, Jinan 250033, Shandong Province, China
| | - Dongjin Wu
- Department of Orthopedics, Second Affiliated Hospital of Shandong University, Jinan 250033, Shandong Province, China
| | - Chunzheng Gao
- Department of Orthopedics, Second Affiliated Hospital of Shandong University, Jinan 250033, Shandong Province, China
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32
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Richner M, Ulrichsen M, Elmegaard SL, Dieu R, Pallesen LT, Vaegter CB. Peripheral nerve injury modulates neurotrophin signaling in the peripheral and central nervous system. Mol Neurobiol 2014; 50:945-70. [PMID: 24752592 DOI: 10.1007/s12035-014-8706-9] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 04/01/2014] [Indexed: 12/21/2022]
Abstract
Peripheral nerve injury disrupts the normal functions of sensory and motor neurons by damaging the integrity of axons and Schwann cells. In contrast to the central nervous system, the peripheral nervous system possesses a considerable capacity for regrowth, but regeneration is far from complete and functional recovery rarely returns to pre-injury levels. During development, the peripheral nervous system strongly depends upon trophic stimulation for neuronal differentiation, growth and maturation. The perhaps most important group of trophic substances in this context is the neurotrophins (NGF, BDNF, NT-3 and NT-4/5), which signal in a complex spatial and timely manner via the two structurally unrelated p75(NTR) and tropomyosin receptor kinase (TrkA, Trk-B and Trk-C) receptors. Damage to the adult peripheral nerves induces cellular mechanisms resembling those active during development, resulting in a rapid and robust increase in the synthesis of neurotrophins in neurons and Schwann cells, guiding and supporting regeneration. Furthermore, the injury induces neurotrophin-mediated changes in the dorsal root ganglia and in the spinal cord, which affect the modulation of afferent sensory signaling and eventually may contribute to the development of neuropathic pain. The focus of this review is on the expression patterns of neurotrophins and their receptors in neurons and glial cells of the peripheral nervous system and the spinal cord. Furthermore, injury-induced changes of expression patterns and the functional consequences in relation to axonal growth and remyelination as well as to neuropathic pain development will be reviewed.
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Affiliation(s)
- Mette Richner
- Danish Research Institute of Translational Neuroscience DANDRITE, Nordic EMBL Partnership, and Lundbeck Foundation Research Center MIND, Department of Biomedicine, Aarhus University, Ole Worms Allé 3, 8000, Aarhus C, Denmark
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33
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Kraemer BR, Yoon SO, Carter BD. The biological functions and signaling mechanisms of the p75 neurotrophin receptor. Handb Exp Pharmacol 2014; 220:121-164. [PMID: 24668472 DOI: 10.1007/978-3-642-45106-5_6] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The p75 neurotrophin receptor (p75(NTR)) regulates a wide range of cellular functions, including programmed cell death, axonal growth and degeneration, cell proliferation, myelination, and synaptic plasticity. The multiplicity of cellular functions governed by the receptor arises from the variety of ligands and co-receptors which associate with p75(NTR) and regulate its signaling. P75(NTR) promotes survival through interactions with Trk receptors, inhibits axonal regeneration via partnerships with Nogo receptor (Nogo-R) and Lingo-1, and promotes apoptosis through association with Sortilin. Signals downstream of these interactions are further modulated through regulated intramembrane proteolysis (RIP) of p75(NTR) and by interactions with numerous cytosolic partners. In this chapter, we discuss the intricate signaling mechanisms of p75(NTR), emphasizing how these signals are differentially regulated to mediate these diverse cellular functions.
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Affiliation(s)
- B R Kraemer
- Department of Biochemistry, Vanderbilt University School of Medicine, 625 Light Hall, Nashville, TN, 37232, USA
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34
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Niklison-Chirou MV, Steinert JR, Agostini M, Knight RA, Dinsdale D, Cattaneo A, Mak TW, Melino G. TAp73 knockout mice show morphological and functional nervous system defects associated with loss of p75 neurotrophin receptor. Proc Natl Acad Sci U S A 2013; 110:18952-7. [PMID: 24190996 PMCID: PMC3839698 DOI: 10.1073/pnas.1221172110] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Total and N-terminal isoform selective p73 knockout mice show a variety of central nervous system defects. Here we show that TAp73 is a transcriptional activator of p75 neurotrophin receptor (p75(NTR)) and that p75(NTR) mRNA and protein levels are strongly reduced in the central and peripheral nervous systems of p73 knockout mice. In parallel, primary cortical neurons from p73 knockout mice showed a reduction in neurite outgrowth and in nerve growth factor-mediated neuronal differentiation, together with reduced miniature excitatory postsynaptic current frequencies and behavioral defects. p73 null mice also have impairments in the peripheral nervous system with reduced thermal sensitivity, axon number, and myelin thickness. At least some of these morphological and functional impairments in p73 null cells can be rescued by p75(NTR) re-expression. Together, these data demonstrate that loss of p75(NTR) contributes to the neurological phenotype of p73 knockout mice.
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Affiliation(s)
| | - Joern R. Steinert
- Toxicology Unit, Medical Research Council, Leicester LE1 9HN, United Kingdom
| | | | - Richard A. Knight
- Toxicology Unit, Medical Research Council, Leicester LE1 9HN, United Kingdom
| | - David Dinsdale
- Toxicology Unit, Medical Research Council, Leicester LE1 9HN, United Kingdom
| | - Antonio Cattaneo
- European Brain Research Institute–Rita Levi-Montalcini, 64 Rome, Italy
| | - Tak W. Mak
- The Campbell Family Institute for Breast Cancer Research, Princess Margaret Hospital, Toronto, ON, Canada M5G 2C1; and
| | - Gerry Melino
- Toxicology Unit, Medical Research Council, Leicester LE1 9HN, United Kingdom
- Biochemistry Laboratory, Istituto Dermopatico dell’Immacolata–Istituto di Ricovero e Cura a Carattere Scientifico and University of Rome Tor Vergata, 00133 Rome, Italy
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Ravasi M, Scuteri A, Pasini S, Bossi M, Menendez VR, Maggioni D, Tredici G. Undifferentiated MSCs are able to myelinate DRG neuron processes through p75. Exp Cell Res 2013; 319:2989-99. [DOI: 10.1016/j.yexcr.2013.08.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 08/02/2013] [Accepted: 08/14/2013] [Indexed: 12/13/2022]
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Gamma knife irradiation of injured sciatic nerve induces histological and behavioral improvement in the rat neuropathic pain model. PLoS One 2013; 8:e61010. [PMID: 23593377 PMCID: PMC3625209 DOI: 10.1371/journal.pone.0061010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Accepted: 03/05/2013] [Indexed: 11/21/2022] Open
Abstract
We examined the effects of gamma knife (GK) irradiation on injured nerves using a rat partial sciatic nerve ligation (PSL) model. GK irradiation was performed at one week after ligation and nerve preparations were made three weeks after ligation. GK irradiation is known to induce immune responses such as glial cell activation in the central nervous system. Thus, we determined the effects of GK irradiation on macrophages using immunoblot and histochemical analyses. Expression of Iba-1 protein, a macrophage marker, was further increased in GK-treated injured nerves as compared with non-irradiated injured nerves. Immunohistochemical study of Iba-1 in GK-irradiated injured sciatic nerves demonstrated Iba-1 positive macrophage accumulation to be enhanced in areas distal to the ligation point. In the same area, myelin debris was also more efficiently removed by GK-irradiation. Myelin debris clearance by macrophages is thought to contribute to a permissive environment for axon growth. In the immunoblot study, GK irradiation significantly increased expressions of βIII-tubulin protein and myelin protein zero, which are markers of axon regeneration and re-myelination, respectively. Toluidine blue staining revealed the re-myelinated fiber diameter to be larger at proximal sites and that the re-myelinated fiber number was increased at distal sites in GK-irradiated injured nerves as compared with non-irradiated injured nerves. These results suggest that GK irradiation of injured nerves facilitates regeneration and re-myelination. In a behavior study, early alleviation of allodynia was observed with GK irradiation in PSL rats. When GK-induced alleviation of allodynia was initially detected, the expression of glial cell line-derived neurotrophic factor (GDNF), a potent analgesic factor, was significantly increased by GK irradiation. These results suggested that GK irradiation alleviates allodynia via increased GDNF. This study provides novel evidence that GK irradiation of injured peripheral nerves may have beneficial effects.
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Ibáñez CF, Simi A. p75 neurotrophin receptor signaling in nervous system injury and degeneration: paradox and opportunity. Trends Neurosci 2012; 35:431-40. [DOI: 10.1016/j.tins.2012.03.007] [Citation(s) in RCA: 155] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Revised: 03/15/2012] [Accepted: 03/15/2012] [Indexed: 12/28/2022]
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Proliferating Immature Schwann Cells Contribute to Nerve Regeneration After Ischemic Peripheral Nerve Injury. J Neuropathol Exp Neurol 2012; 71:511-9. [DOI: 10.1097/nen.0b013e318257fe7b] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
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39
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SIV-induced impairment of neurovascular repair: a potential role for VEGF. J Neurovirol 2012; 18:222-30. [PMID: 22549763 DOI: 10.1007/s13365-012-0102-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Revised: 03/13/2012] [Accepted: 04/13/2012] [Indexed: 12/11/2022]
Abstract
Peripheral nerves and blood vessels travel together closely during development but little is known about their interactions post-injury. The SIV-infected pigtailed macaque model of human immunodeficiency virus (HIV) recapitulates peripheral nervous system pathology of HIV infection. In this study, we assessed the effect of SIV infection on neurovascular regrowth using a validated excisional axotomy model. Six uninfected and five SIV-infected macaques were studied 14 and 70 days after axotomy to characterize regenerating vessels and axons. Blood vessel extension preceded the appearance of regenerating nerve fibers suggesting that vessels serve as scaffolding to guide regenerating axons through extracellular matrix. Vascular endothelial growth factor (VEGF) was expressed along vascular silhouettes by endothelial cells, pericytes, and perivascular cells. VEGF expression correlated with dermal nerve (r=0.68, p=0.01) and epidermal nerve fiber regrowth (r=0.63, p=0.02). No difference in blood vessel growth was observed between SIV-infected and control macaques. In contrast, SIV-infected animals demonstrated altered length, pruning and arborization of nerve fibers as well as alteration of VEGF expression. These results reinforce earlier human primate findings that vessel growth precedes and influences axonal regeneration. The consistency of these observations across human and non-human primates validates the use of the pigtailed-macaque as a preclinical model.
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40
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Extrinsic cellular and molecular mediators of peripheral axonal regeneration. Cell Tissue Res 2012; 349:5-14. [PMID: 22476657 DOI: 10.1007/s00441-012-1389-5] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Accepted: 02/23/2012] [Indexed: 12/11/2022]
Abstract
The ability of injured peripheral nerves to regenerate and reinnervate their original targets is a characteristic feature of the peripheral nervous system (PNS). On the other hand, neurons of the central nervous system (CNS), including retinal ganglion cell (RGC) axons, are incapable of spontaneous regeneration. In the adult PNS, axonal regeneration after injury depends on well-orchestrated cellular and molecular processes that comprise a highly reproducible series of degenerative reactions distal to the site of injury. During this fine-tuned process, named Wallerian degeneration, a remodeling of the distal nerve fragment prepares a permissive microenvironment that permits successful axonal regrowth originating from the proximal nerve fragment. Therefore, a multitude of adjusted intrinsic and extrinsic factors are important for surviving neurons, Schwann cells, macrophages and fibroblasts as well as endothelial cells in order to achieve successful regeneration. The aim of this review is to summarize relevant extrinsic cellular and molecular determinants of successful axonal regeneration in rodents that contribute to the regenerative microenvironment of the PNS.
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41
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Beirowski B, Gustin J, Armour SM, Yamamoto H, Viader A, North BJ, Michán S, Baloh RH, Golden JP, Schmidt RE, Sinclair DA, Auwerx J, Milbrandt J. Sir-two-homolog 2 (Sirt2) modulates peripheral myelination through polarity protein Par-3/atypical protein kinase C (aPKC) signaling. Proc Natl Acad Sci U S A 2011; 108:E952-61. [PMID: 21949390 PMCID: PMC3203793 DOI: 10.1073/pnas.1104969108] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The formation of myelin by Schwann cells (SCs) occurs via a series of orchestrated molecular events. We previously used global expression profiling to examine peripheral nerve myelination and identified the NAD(+)-dependent deacetylase Sir-two-homolog 2 (Sirt2) as a protein likely to be involved in myelination. Here, we show that Sirt2 expression in SCs is correlated with that of structural myelin components during both developmental myelination and remyelination after nerve injury. Transgenic mice lacking or overexpressing Sirt2 specifically in SCs show delays in myelin formation. In SCs, we found that Sirt2 deacetylates Par-3, a master regulator of cell polarity. The deacetylation of Par-3 by Sirt2 decreases the activity of the polarity complex signaling component aPKC, thereby regulating myelin formation. These results demonstrate that Sirt2 controls an essential polarity pathway in SCs during myelin assembly and provide insights into the association between intracellular metabolism and SC plasticity.
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Affiliation(s)
| | - Jason Gustin
- Sigma–Aldrich Biotechnology, St. Louis, MO 63103
| | - Sean M. Armour
- Department of Pathology, Harvard University School of Medicine, Cambridge, MA 02115
| | - Hiroyasu Yamamoto
- Laboratory for Integrative and Systems Physiology, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | | | - Brian J. North
- Department of Pathology, Harvard University School of Medicine, Cambridge, MA 02115
| | - Shaday Michán
- Instituto de Geriatria, Institutos Nacionales de Salud, Mexico D.F., 04510, Mexico
| | - Robert H. Baloh
- Neurology, and
- Hope Center for Neurological Diseases, St. Louis, MO 63110; and
| | - Judy P. Golden
- Department of Anesthesiology, Washington University Pain Center, St. Louis, MO 63110
| | - Robert E. Schmidt
- Pathology, Washington University School of Medicine, St. Louis, MO 63110
- Hope Center for Neurological Diseases, St. Louis, MO 63110; and
| | - David A. Sinclair
- Department of Pathology, Harvard University School of Medicine, Cambridge, MA 02115
| | - Johan Auwerx
- Laboratory for Integrative and Systems Physiology, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Jeffrey Milbrandt
- Departments of Genetics
- Hope Center for Neurological Diseases, St. Louis, MO 63110; and
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Saleh A, Smith DR, Balakrishnan S, Dunn L, Martens C, Tweed CW, Fernyhough P. Tumor necrosis factor-α elevates neurite outgrowth through an NF-κB-dependent pathway in cultured adult sensory neurons: Diminished expression in diabetes may contribute to sensory neuropathy. Brain Res 2011; 1423:87-95. [PMID: 21985959 DOI: 10.1016/j.brainres.2011.09.029] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Revised: 09/14/2011] [Accepted: 09/15/2011] [Indexed: 11/24/2022]
Abstract
The presence of a proinflammatory environment in the sensory neuron axis in diabetes was tested by measuring levels of proinflammatory cytokines in lumbar dorsal root ganglia (DRG) and peripheral nerve from age matched control and streptozotocin (STZ)-induced diabetic rats. The levels of tumor necrosis factor-α (TNFα) and other cytokines were diminished in lumbar DRG from diabetic animals. Consequently, we tested the hypothesis that TNFα modulated axonal plasticity in adult sensory neurons and posited that impairments in this signal transduction pathway may underlie degeneration in diabetic sensory neuropathy. Cultured adult rat sensory neurons were grown under defined conditions and TNFα caused a dose-dependent 2-fold (P<0.05) elevation in neurite outgrowth. Neurons derived from 3 to 5month STZ-induced diabetic rats exhibited significantly reduced levels of neurite outgrowth in response to TNFα. TNFα enhanced NF-κB activity as assessed using Western blotting and plasmid reporter technology. Blockade of TNFα-induction of NF-κB activation caused inhibition of neurite outgrowth in cultured neurons. Immunofluorescent staining for NF-κB subunit p50 within neuronal nuclei revealed that medium to large diameter neurons were most susceptible to NF-κB inhibition and was associated with decreased neurite outgrowth. The results demonstrating reduced cytokine expression in DRG confirm that diabetic sensory neuropathy does not involve a neuroinflammatory component at this stage of the disease in experimental animal models. In addition, it is hypothesized that reduced TNFα expression in the DRG and possibly associated deficits in anterograde transport may contribute to impaired collatoral sprouting and regeneration in target tissue in type 1 diabetes.
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Affiliation(s)
- Ali Saleh
- Division of Neurodegenerative Disorders, St Boniface Hospital Research Centre, Winnipeg, MB, Canada
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43
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Ebenezer GJ, O'Donnell R, Hauer P, Cimino NP, McArthur JC, Polydefkis M. Impaired neurovascular repair in subjects with diabetes following experimental intracutaneous axotomy. Brain 2011; 134:1853-63. [PMID: 21616974 DOI: 10.1093/brain/awr086] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Diabetic complications and vascular disease are closely intertwined. Diabetes mellitus is a well-established risk factor for both large and small vessel vascular changes, and conversely other vascular risk factors confer increased risk for diabetic complications such as peripheral neuropathy, nephropathy and retinopathy. Furthermore, axons and blood vessels share molecular signals for purposes of navigation, regeneration and terminal arborizations. We examined blood vessel, Schwann cell and axonal regeneration using validated axotomy models to study and compare patterns and the relationship of regeneration among these different structures. Ten subjects with diabetes mellitus complicated by neuropathy and 10 healthy controls underwent 3 mm distal thigh punch skin biopsies to create an intracutaneous excision axotomy followed by a concentric 4-mm overlapping biopsy at different time points. Serial sections were immunostained against a pan-axonal marker (PGP9.5), an axonal regenerative marker (GAP43), Schwann cells (p75) and blood vessels (CD31) to visualize regenerating structures in the dermis and epidermis. The regenerative and collateral axonal sprouting rates, blood vessel growth rate and Schwann cell density were quantified using established stereology techniques. Subjects also underwent a chemical 'axotomy' through the topical application of capsaicin, and regenerative sprouting was assessed by the return of intraepidermal nerve fibre density through regenerative regrowth. In the healed 3 mm biopsy sites, collateral and dermal regenerative axonal sprouts grew into the central denervated area in a stereotypic pattern with collateral sprouts growing along the dermal-epidermal junction while regenerative dermal axons, blood vessels and Schwann cells grew from their transected proximal stumps into the deep dermis. Vessel growth preceded axon and Schwann cell migration into the denervated region, perhaps acting as scaffolding for axon and Schwann cell growth. In control subjects, Schwann cell growth was more robust and extended into the superficial dermis, while among subjects with diabetes mellitus, Schwann tubes appeared atrophic and were limited to the mid-dermis. Rates of collateral (P=0.0001), dermal axonal regenerative sprouting (P=0.02), Schwann cell migration (P<0.05) and blood vessel growth (P=0.002) were slower among subjects with diabetes mellitus compared with control subjects. Regenerative deficits are a common theme in diabetes mellitus and may underlie the development of neuropathy. We observed that blood vessel growth recapitulated the pattern seen in ontogeny and preceded regenerating nerve fibres, suggesting that enhancement of blood vessel growth might facilitate axonal regeneration. These models are useful tools for the efficient investigation of neurotrophic and regenerative drugs, and also to explore factors that may differentially affect axonal regeneration.
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Affiliation(s)
- Gigi J Ebenezer
- Department of Neurology, Johns Hopkins University, Baltimore, MD 21287-7609, USA
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Jung J, Cai W, Jang SY, Shin YK, Suh DJ, Kim JK, Park HT. Transient lysosomal activation is essential for p75 nerve growth factor receptor expression in myelinated Schwann cells during Wallerian degeneration. Anat Cell Biol 2011; 44:41-9. [PMID: 21519548 PMCID: PMC3080007 DOI: 10.5115/acb.2011.44.1.41] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Revised: 03/03/2011] [Accepted: 03/03/2011] [Indexed: 12/22/2022] Open
Abstract
Myelinated Schwann cells in the peripheral nervous system express the p75 nerve growth factor receptor (p75NGFR) as a consequence of Schwann cell dedifferentiation during Wallerian degeneration. p75NGFR has been implicated in the remyelination of regenerating nerves. Although many studies have shown various mechanisms underlying Schwann cell dedifferentiation, the molecular mechanism contributing to the re-expression of p75NGFR in differentiated Schwann cells is largely unknown. In the present study, we found that lysosomes were transiently activated in Schwann cells after nerve injury and that the inhibition of lysosomal activation by chloroquine or lysosomal acidification inhibitors prevented p75NGFR expression at the mRNA transcriptional level in an ex vivo Wallerian degeneration model. Lysosomal acidification inhibitors suppressed demyelination, but not axonal degeneration, thereby suggesting that demyelination mediated by lysosomes may be an important signal for inducing p75NGFR expression. Tumor necrosis factor-α (TNF-α) has been suggested to be involved in regulating p75NGFR expression in Schwann cells. In this study, we found that removing TNF-α in vivo did not significantly suppress the induction of both lysosomes and p75NGFR. Thus, these findings suggest that lysosomal activation is tightly correlated with the induction of p75NGFR in demyelinating Schwann cells during Wallerian degeneration.
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Affiliation(s)
- Junyang Jung
- Department of Physiology, Mitochondria Hub Research Center, College of Medicine, Dong-A University, Busan, Korea
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45
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Remahl S, Angeria M, Remahl IN, Carlstedt T, Risling M. Observations at the CNS-PNS Border of Ventral Roots Connected to a Neuroma. Front Neurol 2010; 1:136. [PMID: 21188264 PMCID: PMC3008941 DOI: 10.3389/fneur.2010.00136] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Accepted: 09/28/2010] [Indexed: 01/15/2023] Open
Abstract
Previous studies have shown that numerous sprouts originating from a neuroma, after nerve injury in neonatal animals, can invade spinal nerve roots. However, no study with a focus on how such sprouts behave when they reach the border between the central and peripheral nervous system (CNS–PNS border) has been published. In this study we have in detail examined the CNS–PNS border of ventral roots in kittens with light and electron microscopy after early postnatal sciatic nerve resection. A transient ingrowth of substance P positive axons was observed into the CNS, but no spouts remained 6 weeks after the injury. Using serial sections and electron microscopy it was possible to identify small bundles of unmyelinated axons that penetrated from the root fascicles for a short distance into the CNS. These axons ended blindly, sometimes with a growth cone-like terminal swelling filled with vesicles. The axon bundles were accompanied by p75 positive cells in both the root fascicles and the pia mater, but not in the CNS. It may thus be suggested that neurotrophin presenting p75 positive cells could facilitate axonal growth into the pia mater and that the lack of such cells in the CNS compartment might contribute to the failure of growth into the CNS. A maldevelopment of myelin sheaths at the CNS–PNS border of motor axons was observed and it seems possible that this could have consequences for the propagation of action potential across this region after neonatal nerve injury. Thus, in this first detailed study on the behavior of recurrent sprouts at the CNS–PNS border.
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Affiliation(s)
- Sten Remahl
- Department of Neuroscience, Karolinska Institutet Stockholm Sweden
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Romanelli RJ, Wood TL. Directing traffic in neural cells: determinants of receptor tyrosine kinase localization and cellular responses. J Neurochem 2010; 105:2055-68. [PMID: 18248622 DOI: 10.1111/j.1471-4159.2008.05263.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The trafficking of receptor tyrosine kinases (RTKs) to distinct subcellular locations is essential for the specificity and fidelity of signal transduction and biological responses. This is particularly important in the PNS and CNS in which RTKs mediate key events in the development and maintenance of neurons and glia through a wide range of neural processes, including survival, proliferation, differentiation, neurite outgrowth, and synaptogenesis. The mechanisms that regulate the targeting of RTKs to their subcellular destinations for appropriate signal transduction, however, are still elusive. In this review, we discuss evidence for the spatial organization of signaling machinery into distinct subcellular compartments, as well as the role for ligand specificity, receptor sorting signals, and lipid raft microdomains in RTK targeting and the resultant cellular responses in neural cells.
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Affiliation(s)
- Robert J Romanelli
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, Oregon, USA
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47
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Morisaki S, Nishi M, Fujiwara H, Oda R, Kawata M, Kubo T. Endogenous glucocorticoids improve myelination via Schwann cells after peripheral nerve injury: An in vivo study using a crush injury model. Glia 2010; 58:954-63. [PMID: 20169622 DOI: 10.1002/glia.20977] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Glucocorticoids improve the symptoms of peripheral nerve disorders, such as carpal tunnel syndrome and peripheral neuropathy. The effects of glucocorticoids are mainly anti-inflammatory, but the mechanisms of their effects in peripheral nerve disorders remain unclear. Schwann cells of the peripheral nerves express glucocorticoid receptors (GR), and glucocorticoids enhance the rate of myelin formation in vitro. Therefore, it is possible that the clinical improvement of peripheral nerve disorders by glucocorticoids is due, at least in part, to the modulation of myelination. In this study, an adrenalectomy (ADX) was performed, and followed by a daily injection of either low dose (1 mg/kg) or high dose (10 mg/kg) corticosterone (CORT). We then simulated a crush injury of the sciatic nerves. A sham ADX operation, followed by a simulated crush injury, was conducted as a control. Immunohistochemistry showed that the nuclei of in vivo Schwann cells expressed GR and that glucocorticoids impacted the GR immunoreactivity of the Schwann cells. The mRNA and protein expression of myelin basic protein was significantly lower in the animals given ADX with vehicle than in the sham operation group. However, the expression was restored in the low-dose CORT replacement group. Morphological analyses showed that the ADX with vehicle group had a significantly lower myelin thickness than did the low-dose CORT replacement group and the sham operation group. These results suggest that endogenous glucocorticoids have an important role in myelination through the GR in Schwann cells after an in vivo peripheral nerve injury.
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Affiliation(s)
- Shinsuke Morisaki
- Department of Orthopedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan.
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48
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Yuan TF. Is inhibition of axonal regeneration by astrocytes, in the dorsal part of the spinal cord, regulated by p75 receptor? Brain 2010; 133:e144; author reply e145. [PMID: 20176577 DOI: 10.1093/brain/awq018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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49
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Li FQ, Fowler KA, Neil JE, Colton CA, Vitek MP. An apolipoprotein E-mimetic stimulates axonal regeneration and remyelination after peripheral nerve injury. J Pharmacol Exp Ther 2010; 334:106-15. [PMID: 20406857 DOI: 10.1124/jpet.110.167882] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Elevated apolipoprotein E (apoE) synthesis within crushed sciatic nerves advocates that apoE could benefit axonal repair and reconstruction of axonal and myelin membranes. We created an apoE-mimetic peptide, COG112 (acetyl-RQIKIWFQNRRMKWKKCLRVRLASHLRKLRKRLL-amide), and found that postinjury treatment with COG112 significantly improved recovery of motor and sensory function following sciatic nerve crush in C57BL/6 mice. Morphometric analysis of injured sciatic nerves revealed that COG112 promoted axonal regrowth after 2 weeks of treatment. More strikingly, the thickness of myelin sheaths was increased by COG112 treatment. Consistent with these histological findings, COG112 potently elevated growth associated protein 43 (GAP-43) and peripheral myelin protein zero (P0), which are markers of axon regeneration and remyelination, respectively. Electron microscopic examination further suggested that the apoE-mimetic COG112 may increase clearance of myelin debris. Schwann cell uptake of cholesterol-containing low-density lipoprotein particles was selectively enhanced by COG112 treatment in a Schwann cell line S16. Moreover, COG112 significantly promoted axon elongation in primary dorsal root ganglion cultures from rat pups. Considering that cholesterol and lipids are needed for reconstructing myelin sheaths and axon extension, these data support a hypothesis where supplementation with exogenous apoE-mimetics such as COG112 may be a promising strategy for restoring lost functional and structural elements following nerve injury.
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Affiliation(s)
- Feng-Qiao Li
- Cognosci, Inc., Research Triangle Park, NC 27709, USA.
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50
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Ceyhan GO, Demir IE, Rauch U, Bergmann F, Müller MW, Büchler MW, Friess H, Schäfer KH. Pancreatic neuropathy results in "neural remodeling" and altered pancreatic innervation in chronic pancreatitis and pancreatic cancer. Am J Gastroenterol 2009; 104:2555-65. [PMID: 19568227 DOI: 10.1038/ajg.2009.380] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Chronic pancreatitis (CP) and pancreatic cancer (PCa) are characterized by intrapancreatic neuropathic alterations, including increased neural density and hypertrophy, pancreatic neuritis and neural invasion (NI) by cancer cells in PCa. The aim of this study was to identify the influence of these neuropathic changes on the quality of pancreatic innervation, intrapancreatic glia, and visceral pain. METHODS Pancreatic nerve fiber qualities were characterized by immunohistochemical visualization of various markers, including those for sympathetic (tyrosine hydroxylase, TH) and cholinergic innervation (choline acetyltransferase, ChAT), as well as the glial transcription factor, Sox10, and the neuroepithelial progenitor cell marker, Nestin, in normal pancreas (NP, n=16), CP (n=20), and PCa (n=20) patients. The neural immunoreactivity scores of these markers were correlated with the severity of intrapancreatic neuropathic changes and with abdominal pain sensation of patients. RESULTS Pancreatic sympathetic innervation was significantly reduced in CP and PCa, whereas parasympathetic innervation did not show major changes. Nestin neuro-immunoreactivity was stronger, and Sox10-immunoreactivity was weaker in CP and PCa than in NP. Pancreatic sympathetic and cholinergic innervation was noticeably decreased in patients with severe pancreatic neuritis, NI by cancer cells, or abdominal pain. Moreover, the neural immunoreactivity for Sox10 and Nestin also varied with intrapancreatic neuropathic alterations and abdominal pain. CONCLUSIONS The quality of intrapancreatic nerve fibers and the activation state of intrapancreatic glia in CP and PCa are strikingly different from those in normal pancreas. This novel phenomenon of "neural remodeling" shows how pancreatic neuropathic pain and "visceral neuropathy" are associated with altered pancreatic innervation in CP and PCa.
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Affiliation(s)
- Güralp Onur Ceyhan
- Department of Surgery, Klinikum Rechts der Isar, Technische Universität München, Munich D-81675, Germany.
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