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Chambel SS, Cruz CD. Axonal growth inhibitors and their receptors in spinal cord injury: from biology to clinical translation. Neural Regen Res 2023; 18:2573-2581. [PMID: 37449592 DOI: 10.4103/1673-5374.373674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2023] Open
Abstract
Axonal growth inhibitors are released during traumatic injuries to the adult mammalian central nervous system, including after spinal cord injury. These molecules accumulate at the injury site and form a highly inhibitory environment for axonal regeneration. Among these inhibitory molecules, myelin-associated inhibitors, including neurite outgrowth inhibitor A, oligodendrocyte myelin glycoprotein, myelin-associated glycoprotein, chondroitin sulfate proteoglycans and repulsive guidance molecule A are of particular importance. Due to their inhibitory nature, they represent exciting molecular targets to study axonal inhibition and regeneration after central injuries. These molecules are mainly produced by neurons, oligodendrocytes, and astrocytes within the scar and in its immediate vicinity. They exert their effects by binding to specific receptors, localized in the membranes of neurons. Receptors for these inhibitory cues include Nogo receptor 1, leucine-rich repeat, and Ig domain containing 1 and p75 neurotrophin receptor/tumor necrosis factor receptor superfamily member 19 (that form a receptor complex that binds all myelin-associated inhibitors), and also paired immunoglobulin-like receptor B. Chondroitin sulfate proteoglycans and repulsive guidance molecule A bind to Nogo receptor 1, Nogo receptor 3, receptor protein tyrosine phosphatase σ and leucocyte common antigen related phosphatase, and neogenin, respectively. Once activated, these receptors initiate downstream signaling pathways, the most common amongst them being the RhoA/ROCK signaling pathway. These signaling cascades result in actin depolymerization, neurite outgrowth inhibition, and failure to regenerate after spinal cord injury. Currently, there are no approved pharmacological treatments to overcome spinal cord injuries other than physical rehabilitation and management of the array of symptoms brought on by spinal cord injuries. However, several novel therapies aiming to modulate these inhibitory proteins and/or their receptors are under investigation in ongoing clinical trials. Investigation has also been demonstrating that combinatorial therapies of growth inhibitors with other therapies, such as growth factors or stem-cell therapies, produce stronger results and their potential application in the clinics opens new venues in spinal cord injury treatment.
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Affiliation(s)
- Sílvia Sousa Chambel
- Experimental Biology Unit, Department of Biomedicine, Faculty of Medicine of Porto; Translational NeuroUrology, Instituto de Investigação e Inovação em Saúde-i3S and IBMC, Universidade do Porto, Porto, Portugal
| | - Célia Duarte Cruz
- Experimental Biology Unit, Department of Biomedicine, Faculty of Medicine of Porto; Translational NeuroUrology, Instituto de Investigação e Inovação em Saúde-i3S and IBMC, Universidade do Porto, Porto, Portugal
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2
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Howard EM, Strittmatter SM. Development of neural repair therapy for chronic spinal cord trauma: soluble Nogo receptor decoy from discovery to clinical trial. Curr Opin Neurol 2023; 36:516-522. [PMID: 37865850 PMCID: PMC10841037 DOI: 10.1097/wco.0000000000001205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2023]
Abstract
PURPOSE OF REVIEW After traumatic spinal cord injury (SCI), neurological deficits persist due to the disconnection of surviving neurons. While repair of connectivity may restore function, no medical therapy exists today.This review traces the development of the neural repair-based therapeutic AXER-204 from animal studies to the recent clinical trial for chronic cervical SCI. RECENT FINDINGS Molecular studies reveal a Nogo-66 Receptor 1 (NgR1, RTN4R) pathway inhibiting axon regeneration, sprouting, and plasticity in the adult mammalian central nervous system (CNS). Rodent and nonhuman primate studies demonstrate that the soluble receptor decoy NgR(310)ecto-Fc or AXER-204 promotes neural repair and functional recovery in transection and contusion SCI. Recently, this biological agent completed a first-in-human and randomized clinical trial for chronic cervical SCI. The intervention was safe and well tolerated. Across all participants, upper extremity strength did not improve with treatment. However, posthoc and biomarker analyses suggest that AXER-204 may benefit treatment-naïve patients with incomplete SCI in the chronic stage. SUMMARY NgR1 signaling restricts neurological recovery in animal studies of CNS injury. The recent clinical trial of AXER-204 provides encouraging signals supporting future focused trials of this neural repair therapeutic. Further, AXER-204 studies provide a roadmap for the development of additional and synergistic therapies for chronic SCI.
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Affiliation(s)
- Elisa M. Howard
- Departments of Neuroscience and Neurology, Yale School of Medicine, New Haven, CT, USA
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3
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Sekine Y, Wang X, Kikkawa K, Honda S, Strittmatter SM. Amino-terminal proteolytic fragment of the axon growth inhibitor Nogo-A (Rtn4A) is upregulated by injury and promotes axon regeneration. J Biol Chem 2023; 299:105232. [PMID: 37690690 PMCID: PMC10622843 DOI: 10.1016/j.jbc.2023.105232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 08/28/2023] [Accepted: 08/31/2023] [Indexed: 09/12/2023] Open
Abstract
After adult mammalian central nervous system injury, axon regeneration is extremely limited or absent, resulting in persistent neurological deficits. Axon regeneration failure is due in part to the presence of inhibitory proteins, including NogoA (Rtn4A), from which two inhibitory domains have been defined. When these inhibitory domains are deleted, but an amino-terminal domain is still expressed in a gene trap line, mice show axon regeneration and enhanced recovery from injury. In contrast, when there is no amino-terminal Nogo-A fragment in the setting of inhibitory domain deletion, then axon regeneration and recovery are indistinguishable from WT. These data indicated that an amino-terminal Nogo-A fragment derived from the gene trap might promote axon regeneration, but this had not been tested directly and production of this fragment without gene targeting was unclear. Here, we describe posttranslation production of an amino-terminal fragment of Nogo-A from the intact gene product. This fragment is created by proteolysis near amino acid G214-N215 and levels are enhanced by axotomy. Furthermore, this fragment promotes axon regeneration in vitro and acts cell autonomously in neurons, in contrast to the inhibitory extracellular action of other Nogo-A domains.Proteins interacting with the amino-terminal Nogo-A fragment by immunoprecipitation include HSPA8 (HSC70, HSP7C). Suppression of HSPA8 expression by shRNA decreases axon regeneration from cerebral cortical neurons and overexpression increases axon regeneration. Moreover, the amino-terminal Nogo-A fragment increases HSPA8 chaperone activity. These data provide an explanation for varied results in different gene-targeted Nogo-A mice, as well as revealing an axon regeneration promoting domain of Nogo-A.
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Affiliation(s)
- Yuichi Sekine
- Department of Neuroscience and Neurology, Cellular Neuroscience, Neurodegeneration & Repair Program, Yale School of Medicine, New Haven, Connecticut, USA; Department of Cell Biology, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Xingxing Wang
- Department of Neuroscience and Neurology, Cellular Neuroscience, Neurodegeneration & Repair Program, Yale School of Medicine, New Haven, Connecticut, USA
| | - Kazuna Kikkawa
- Department of Cell Biology, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Sachie Honda
- Department of Cell Biology, Kyoto Pharmaceutical University, Kyoto, Japan
| | - Stephen M Strittmatter
- Department of Neuroscience and Neurology, Cellular Neuroscience, Neurodegeneration & Repair Program, Yale School of Medicine, New Haven, Connecticut, USA.
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Zhao M, Li J, Gao Z, Guo D, Yang Y, Wang F, Wang L, Yang Y, He X, Li H, Chang S. miR-145a-5p/Plexin-A2 promotes the migration of OECs and transplantation of miR-145a-5p engineered OECs promotes the functional recovery in rats with SCI. Neurobiol Dis 2023; 182:106129. [PMID: 37068642 DOI: 10.1016/j.nbd.2023.106129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 04/10/2023] [Accepted: 04/14/2023] [Indexed: 04/19/2023] Open
Abstract
BACKGROUND Olfactory ensheathing cells (OECs) serve as a bridge by migrating at the site of spinal cord injury (SCI) to facilitate the repair of the neural structure and neural function. However, OEC migration at the injury site not only faces the complex and disordered internal environment but also is closely associated with the migration ability of OECs. METHODS We extracted OECs from the olfactory bulb of SD rats aged <7 days old. We verified the micro ribonucleic acid (miR)-145a-5p expression level in the gene chip after SCI and OEC transplantation using quantitative reverse transcription (qRT)-polymerase chain reaction (PCR). The possible target gene Plexin-A2 of miR-145a-5p was screened using bioinformatics and was verified using dual-luciferase reporter assay, Western blot, and qRT-PCR. The effect of miR-145a-5p/plexin-A2 on OEC migration ability was verified by wound healing assay, Transwell cell migration assay, and immunohistochemistry. Nerve regeneration was observed at the injured site of the spinal cord after OEC transplantation using tissue immunofluorescence and magnetic resonance imaging, diffusion tensor imaging, and the Basso-Beattie-Bresnahan locomotor rating scale were further used for imaging and functional evaluation. RESULTS miR-145a-5p expression in the injured spinal cord tissue after SCI considerably decreased, while Plexin-A2 expression significantly increased. OEC transplantation can reverse miR-145a-5p and Plexin-A2 expression after SCI. miR-145a-5p overexpression enhanced the intrinsic migration ability of OECs. As a target gene of miR-145a-5p, Plexin-A2 hinders OEC migration. OEC transplantation overexpressing miR-145a-5p after SCI can increase miR-145a-5p levels in the spinal cord, reduce Plexin-A2 expression in the OECs and the spinal cord tissue, and promote OEC migration and distribution at the injured site. OEC transplantation overexpressing miR-145a-5p can promote the regeneration and repair of neural morphology and neural function. CONCLUSIONS Our study demonstrated that miR-145a-5p could promote OEC migration to the injured spinal cord after cell transplantation by down-regulating the target gene Plexin-A2, thereby repairing the neural structure and function after SCI in rats.
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Affiliation(s)
- MinChao Zhao
- Department of Orthopaedics, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province 710004, China
| | - Jiaxi Li
- Department of Orthopaedics, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province 710004, China
| | - Zhengchao Gao
- Department of Orthopaedics, Shaanxi Provincial People's Hospital, 256 Youyi West Road, Xi'an 710068, Shaanxi, China
| | - Dong Guo
- Department of Orthopaedics, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province 710004, China
| | - Yubing Yang
- Department of Orthopaedics, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province 710004, China
| | - Fang Wang
- Department of Orthopaedics, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province 710004, China
| | - Lumin Wang
- Gastroenterology department, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710100, China
| | - Yang Yang
- School of Public Health, Shaanxi University of Chinese Medicine, Xianyang 712046, China
| | - Xijing He
- Department of Orthopaedics, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province 710004, China; Department of Orthopaedics, Xi'an International Medical Center Hospital, Xi'an, Shaanxi 710100, China
| | - Haopeng Li
- Department of Orthopaedics, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province 710004, China.
| | - Su'e Chang
- Department of Orthopaedics, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province 710004, China.
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5
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Mu JD, Ma LX, Zhang Z, Qian X, Zhang QY, Ma LH, Sun TY. The factors affecting neurogenesis after stroke and the role of acupuncture. Front Neurol 2023; 14:1082625. [PMID: 36741282 PMCID: PMC9895425 DOI: 10.3389/fneur.2023.1082625] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 01/03/2023] [Indexed: 01/22/2023] Open
Abstract
Stroke induces a state of neuroplasticity in the central nervous system, which can lead to neurogenesis phenomena such as axonal growth and synapse formation, thus affecting stroke outcomes. The brain has a limited ability to repair ischemic damage and requires a favorable microenvironment. Acupuncture is considered a feasible and effective neural regulation strategy to improve functional recovery following stroke via the benign modulation of neuroplasticity. Therefore, we summarized the current research progress on the key factors and signaling pathways affecting neurogenesis, and we also briefly reviewed the research progress of acupuncture to improve functional recovery after stroke by promoting neurogenesis. This study aims to provide new therapeutic perspectives and strategies for the recovery of motor function after stroke based on neurogenesis.
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Affiliation(s)
- Jie-Dan Mu
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Liang-Xiao Ma
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China,The Key Unit of State Administration of Traditional Chines Medicine, Evaluation of Characteristic Acupuncture Therapy, Beijing, China,*Correspondence: Liang-Xiao Ma ✉
| | - Zhou Zhang
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Xu Qian
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Qin-Yong Zhang
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Ling-Hui Ma
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
| | - Tian-Yi Sun
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing, China
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6
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Vaccaro G, Dumoulin A, Zuñiga NR, Bandtlow CE, Stoeckli ET. The Nogo-66 Receptors NgR1 and NgR3 Are Required for Commissural Axon Pathfinding. J Neurosci 2022; 42:4087-4100. [PMID: 35437280 PMCID: PMC9121835 DOI: 10.1523/jneurosci.1390-21.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 04/08/2022] [Accepted: 04/12/2022] [Indexed: 11/30/2022] Open
Abstract
Nogo-66 receptors (NgR1-3) are glycosylphosphatidyl inositol-linked proteins that belong to the leucine-rich repeat superfamily. Through binding to myelin-associated inhibitors, NgRs contribute to the inhibition of axonal regeneration after spinal cord injury. Their role in limiting synaptic plasticity and axonal outgrowth in the adult CNS has been described previously, but not much is known about their role during the development of the nervous system. Here, we show that NgR1 and NgR3 mRNAs are expressed during spinal cord development of the chicken embryo. In particular, they are expressed in the dI1 subpopulation of commissural neurons during the time when their axons navigate toward and across the floorplate, the ventral midline of the spinal cord. To assess a potential role of NgR1 and NgR3 in axon guidance, we downregulated them using in ovo RNAi and analyzed the trajectory of commissural axons by tracing them in open-book preparations of spinal cords. Our results show that loss of either NgR1 or NgR3 causes axons to stall in the midline area and to interfere with the rostral turn of postcrossing axons. In addition, we also show that NgR1, but not NgR3, requires neuronal PlexinA2 for the regulation of commissural axon guidance.SIGNIFICANCE STATEMENT Over the last decades, many studies have focused on the role of NgRs, particularly NgR1, in axonal regeneration in the injured adult CNS. Here, we show a physiological role of NgRs in guiding commissural axons during early development of the chicken spinal cord in vivo Both NgR1 and NgR3 are required for midline crossing and subsequent turning of postcrossing axons into the longitudinal axis of the spinal cord. NgR1, but not NgR3, forms a receptor complex with PlexinA2 during axon guidance. Overall, these findings provide a link between neural regenerative mechanisms and developmental processes.
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Affiliation(s)
- Giuseppe Vaccaro
- Institute of Neurobiochemistry, Biocenter, Medical University of Innsbruck, Innsbruck, 6020, Austria
- Department of Molecular Life Sciences, Neuroscience Center Zurich, Zurich, 8057, Switzerland
| | - Alexandre Dumoulin
- Department of Molecular Life Sciences, Neuroscience Center Zurich, Zurich, 8057, Switzerland
| | - Nikole R Zuñiga
- Department of Molecular Life Sciences, Neuroscience Center Zurich, Zurich, 8057, Switzerland
| | - Christine E Bandtlow
- Institute of Neurobiochemistry, Biocenter, Medical University of Innsbruck, Innsbruck, 6020, Austria
| | - Esther T Stoeckli
- Department of Molecular Life Sciences, Neuroscience Center Zurich, Zurich, 8057, Switzerland
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7
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Boulan B, Ravanello C, Peyrel A, Bosc C, Delphin C, Appaix F, Denarier E, Kraut A, Jacquier-Sarlin M, Fournier A, Andrieux A, Gory-Fauré S, Deloulme JC. CRMP4-mediated fornix development involves Semaphorin-3E signaling pathway. eLife 2021; 10:e70361. [PMID: 34860155 PMCID: PMC8683083 DOI: 10.7554/elife.70361] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 12/02/2021] [Indexed: 12/25/2022] Open
Abstract
Neurodevelopmental axonal pathfinding plays a central role in correct brain wiring and subsequent cognitive abilities. Within the growth cone, various intracellular effectors transduce axonal guidance signals by remodeling the cytoskeleton. Semaphorin-3E (Sema3E) is a guidance cue implicated in development of the fornix, a neuronal tract connecting the hippocampus to the hypothalamus. Microtubule-associated protein 6 (MAP6) has been shown to be involved in the Sema3E growth-promoting signaling pathway. In this study, we identified the collapsin response mediator protein 4 (CRMP4) as a MAP6 partner and a crucial effector in Sema3E growth-promoting activity. CRMP4-KO mice displayed abnormal fornix development reminiscent of that observed in Sema3E-KO mice. CRMP4 was shown to interact with the Sema3E tripartite receptor complex within detergent-resistant membrane (DRM) domains, and DRM domain integrity was required to transduce Sema3E signaling through the Akt/GSK3 pathway. Finally, we showed that the cytoskeleton-binding domain of CRMP4 is required for Sema3E's growth-promoting activity, suggesting that CRMP4 plays a role at the interface between Sema3E receptors, located in DRM domains, and the cytoskeleton network. As the fornix is affected in many psychiatric diseases, such as schizophrenia, our results provide new insights to better understand the neurodevelopmental components of these diseases.
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Affiliation(s)
- Benoît Boulan
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
| | - Charlotte Ravanello
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
| | - Amandine Peyrel
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
| | - Christophe Bosc
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
| | - Christian Delphin
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
| | - Florence Appaix
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
| | - Eric Denarier
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
| | - Alexandra Kraut
- Univ. Grenoble Alpes, Inserm, CEA, UMR BioSanté U1292, CNRS, CEAGrenobleFrance
| | | | - Alyson Fournier
- Department of Neurology and Neurosurgery, Montréal Neurological Institute, McGill UniversityMontréalCanada
| | - Annie Andrieux
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
| | - Sylvie Gory-Fauré
- Univ. Grenoble Alpes, Inserm, U1216, CEA, Grenoble Institut NeurosciencesGrenobleFrance
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Chen L, Hu Q, Liu H, Zhao Y, Chan SO, Wang J. Nogo-A Induced Polymerization of Microtubule Is Involved in the Inflammatory Heat Hyperalgesia in Rat Dorsal Root Ganglion Neurons. Int J Mol Sci 2021; 22:ijms221910360. [PMID: 34638704 PMCID: PMC8508904 DOI: 10.3390/ijms221910360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 09/13/2021] [Accepted: 09/21/2021] [Indexed: 11/16/2022] Open
Abstract
The microtubule, a major constituent of cytoskeletons, was shown to bind and interact with transient receptor potential vanilloid subfamily member 1 (TRPV1), and serves a pivotal role to produce thermal hyperalgesia in inflammatory pain. Nogo-A is a modulator of microtubule assembly and plays a key role in maintaining the function of TRPV1 in inflammatory heat pain. However, whether the microtubule dynamics modulated by Nogo-A in dorsal root ganglion (DRG) neurons participate in the inflammatory pain is not elucidated. Here we reported that the polymerization of microtubules in the DRG neurons, as indicated by the acetylated α-tubulin, tubulin polymerization-promoting protein 3 (TPPP3), and microtubule numbers, was significantly elevated in the complete Freund’s adjuvant (CFA) induced inflammatory pain. Consistent with our previous results, knock-out (KO) of Nogo-A protein significantly attenuated the heat hyperalgesia 72 h after CFA injection and decreased the microtubule polymerization via up-regulation of phosphorylation of collapsin response mediator protein 2 (CRMP2) in DRG. The colocalization of acetylated α-tubulin and TRPV1 in DRG neurons was also reduced dramatically in Nogo-A KO rats under inflammatory pain. Moreover, the down-regulation of TRPV1 in DRG of Nogo-A KO rats after injection of CFA was reversed by intrathecal injection of paclitaxel, a microtubule stabilizer. Furthermore, intrathecal injection of nocodazole (a microtubule disruptor) attenuated significantly the CFA-induced inflammatory heat hyperalgesia and the mechanical pain in a rat model of spared nerve injury (SNI). In these SNI cases, the Nogo-A and acetylated α-tubulin in DRG were also significantly up-regulated. We conclude that the polymerization of microtubules promoted by Nogo-A in DRG contributes to the development of inflammatory heat hyperalgesia mediated by TRPV1.
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Affiliation(s)
- Ling Chen
- Department of Human Anatomy, Histology & Embryology, School of Basic Medical Sciences, Peking University, Beijing 100191, China; (L.C.); (Q.H.); (H.L.); (Y.Z.)
| | - Qiguo Hu
- Department of Human Anatomy, Histology & Embryology, School of Basic Medical Sciences, Peking University, Beijing 100191, China; (L.C.); (Q.H.); (H.L.); (Y.Z.)
| | - Huaicun Liu
- Department of Human Anatomy, Histology & Embryology, School of Basic Medical Sciences, Peking University, Beijing 100191, China; (L.C.); (Q.H.); (H.L.); (Y.Z.)
| | - Yan Zhao
- Department of Human Anatomy, Histology & Embryology, School of Basic Medical Sciences, Peking University, Beijing 100191, China; (L.C.); (Q.H.); (H.L.); (Y.Z.)
| | - Sun-On Chan
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
- Correspondence: (S.-O.C.); (J.W.); Tel.: +85-2-3943-6898 (S.-O.C.); +86-10-8280-1119 (J.W.)
| | - Jun Wang
- Department of Human Anatomy, Histology & Embryology, School of Basic Medical Sciences, Peking University, Beijing 100191, China; (L.C.); (Q.H.); (H.L.); (Y.Z.)
- Correspondence: (S.-O.C.); (J.W.); Tel.: +85-2-3943-6898 (S.-O.C.); +86-10-8280-1119 (J.W.)
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9
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Pradhan LK, Das SK. The Regulatory Role of Reticulons in Neurodegeneration: Insights Underpinning Therapeutic Potential for Neurodegenerative Diseases. Cell Mol Neurobiol 2021; 41:1157-1174. [PMID: 32504327 DOI: 10.1007/s10571-020-00893-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 05/29/2020] [Indexed: 02/06/2023]
Abstract
In the last few decades, cytoplasmic organellar dysfunction, such as that of the endoplasmic reticulum (ER), has created a new area of research interest towards the development of serious health maladies including neurodegenerative diseases. In this context, the extensively dispersed family of ER-localized proteins, i.e. reticulons (RTNs), is gaining interest because of its regulative control over neural regeneration. As most neurodegenerative diseases are pathologically manifested with the accretion of misfolded proteins with subsequent induction of ER stress, the regulatory role of RTNs in neural dysfunction cannot be ignored. With the limited information available in the literature, delineation of the functional connection between rising consequences of neurodegenerative diseases and RTNs need to be elucidated. In this review, we provide a broad overview on the recently revealed regulatory roles of reticulons in the pathophysiology of several health maladies, with special emphasis on neurodegeneration. Additionally, we have also recapitulated the decisive role of RTN4 in neurite regeneration and highlighted how neurodegeneration and proteinopathies are mechanistically linked with each other through specific RTN paralogues. With the recent findings advocating zebrafish Rtn4b (a mammalian Nogo-A homologue) downregulation following central nervous system (CNS) lesion, RTNs provides new insight into the CNS regeneration. However, there are controversies with respect to the role of Rtn4b in zebrafish CNS regeneration. Given these controversies, the connection between the unique regenerative capabilities of zebrafish CNS by distinct compensatory mechanisms and Rtn4b signalling pathway could shed light on the development of new therapeutic strategies against serious neurodegenerative diseases.
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Affiliation(s)
- Lilesh Kumar Pradhan
- Neurobiology Laboratory, Centre for Biotechnology, Siksha 'O' Anusandhan (Deemed To Be University), Kalinga Nagar, Bhubaneswar, 751003, India
| | - Saroj Kumar Das
- Neurobiology Laboratory, Centre for Biotechnology, School of Pharmaceutical Sciences, Siksha 'O' Anusandhan (Deemed To Be University), Kalinga Nagar, Bhubaneswar, 751003, India.
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10
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Van Battum E, Heitz-Marchaland C, Zagar Y, Fouquet S, Kuner R, Chédotal A. Plexin-B2 controls the timing of differentiation and the motility of cerebellar granule neurons. eLife 2021; 10:60554. [PMID: 34100719 PMCID: PMC8211449 DOI: 10.7554/elife.60554] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 06/07/2021] [Indexed: 11/13/2022] Open
Abstract
Plexin-B2 deletion leads to aberrant lamination of cerebellar granule neurons (CGNs) and Purkinje cells. Although in the cerebellum Plexin-B2 is only expressed by proliferating CGN precursors in the outer external granule layer (oEGL), its function in CGN development is still elusive. Here, we used 3D imaging, in vivo electroporation and live-imaging techniques to study CGN development in novel cerebellum-specific Plxnb2 conditional knockout mice. We show that proliferating CGNs in Plxnb2 mutants not only escape the oEGL and mix with newborn postmitotic CGNs. Furthermore, motility of mitotic precursors and early postmitotic CGNs is altered. Together, this leads to the formation of ectopic patches of CGNs at the cerebellar surface and an intermingling of normally time-stamped parallel fibers in the molecular layer (ML), and aberrant arborization of Purkinje cell dendrites. There results suggest that Plexin-B2 restricts CGN motility and might have a function in cytokinesis.
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Affiliation(s)
- Eljo Van Battum
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | | | - Yvrick Zagar
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Stéphane Fouquet
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Rohini Kuner
- Pharmacology Institute, Heidelberg University, Heidelberg, Germany
| | - Alain Chédotal
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
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11
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Cuveillier C, Boulan B, Ravanello C, Denarier E, Deloulme JC, Gory-Fauré S, Delphin C, Bosc C, Arnal I, Andrieux A. Beyond Neuronal Microtubule Stabilization: MAP6 and CRMPS, Two Converging Stories. Front Mol Neurosci 2021; 14:665693. [PMID: 34025352 PMCID: PMC8131560 DOI: 10.3389/fnmol.2021.665693] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 04/09/2021] [Indexed: 12/21/2022] Open
Abstract
The development and function of the central nervous system rely on the microtubule (MT) and actin cytoskeletons and their respective effectors. Although the structural role of the cytoskeleton has long been acknowledged in neuronal morphology and activity, it was recently recognized to play the role of a signaling platform. Following this recognition, research into Microtubule Associated Proteins (MAPs) diversified. Indeed, historically, structural MAPs—including MAP1B, MAP2, Tau, and MAP6 (also known as STOP);—were identified and described as MT-binding and -stabilizing proteins. Extensive data obtained over the last 20 years indicated that these structural MAPs could also contribute to a variety of other molecular roles. Among multi-role MAPs, MAP6 provides a striking example illustrating the diverse molecular and cellular properties of MAPs and showing how their functional versatility contributes to the central nervous system. In this review, in addition to MAP6’s effect on microtubules, we describe its impact on the actin cytoskeleton, on neuroreceptor homeostasis, and its involvement in signaling pathways governing neuron development and maturation. We also discuss its roles in synaptic plasticity, brain connectivity, and cognitive abilities, as well as the potential relationships between the integrated brain functions of MAP6 and its molecular activities. In parallel, the Collapsin Response Mediator Proteins (CRMPs) are presented as examples of how other proteins, not initially identified as MAPs, fall into the broader MAP family. These proteins bind MTs as well as exhibiting molecular and cellular properties very similar to MAP6. Finally, we briefly summarize the multiple similarities between other classical structural MAPs and MAP6 or CRMPs.In summary, this review revisits the molecular properties and the cellular and neuronal roles of the classical MAPs, broadening our definition of what constitutes a MAP.
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12
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Ji ZS, Li JP, Fu CH, Luo JX, Yang H, Zhang GW, Wu W, Lin HS. Spastin interacts with collapsin response mediator protein 3 to regulate neurite growth and branching. Neural Regen Res 2021; 16:2549-2556. [PMID: 33907047 PMCID: PMC8374569 DOI: 10.4103/1673-5374.313052] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Cytoskeletal microtubule rearrangement and movement are crucial in the repair of spinal cord injury. Spastin plays an important role in the regulation of microtubule severing. Both spastin and collapsin response mediator proteins can regulate neurite growth and branching; however, whether spastin interacts with collapsin response mediator protein 3 (CRMP3) during this process remains unclear, as is the mechanism by which CRMP3 participates in the repair of spinal cord injury. In this study, we used a proteomics approach to identify key proteins associated with spinal cord injury repair. We then employed liquid chromatography-mass spectrometry to identify proteins that were able to interact with glutathione S-transferase-spastin. Then, co-immunoprecipitation and staining approaches were used to evaluate potential interactions between spastin and CRMP3. Finally, we co-transfected primary hippocampal neurons with CRMP3 and spastin to evaluate their role in neurite outgrowth. Mass spectrometry identified the role of CRMP3 in the spinal cord injury repair process. Liquid chromatography-mass spectrometry pulldown assays identified three CRMP3 peptides that were able to interact with spastin. CRMP3 and spastin were co-expressed in the spinal cord and were able to interact with one another in vitro and in vivo. Lastly, CRMP3 overexpression was able to enhance the ability of spastin to promote neurite growth and branching. Therefore, our results confirm that spastin and CRMP3 play roles in spinal cord injury repair by regulating neurite growth and branching. These proteins may therefore be novel targets for spinal cord injury repair. The Institutional Animal Care and Use Committee of Jinan University, China approved this study (approval No. IACUS-20181008-03) on October 8, 2018.
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Affiliation(s)
- Zhi-Sheng Ji
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong Province, China
| | - Jian-Ping Li
- Guangdong-Hong Kong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, Guangdong Province, China
| | - Chao-Hua Fu
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou; Department of Orthopedics, Jiangmen Hospital of Sun Yat-sen University, Jiangmen, Guangdong Province, China
| | - Jian-Xian Luo
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong Province, China
| | - Hua Yang
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong Province, China
| | - Guo-Wei Zhang
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong Province, China
| | - Wutian Wu
- Guangdong-Hong Kong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, Guangdong Province; Re-Stem Biotechnology Co., Ltd., Suzhou, Jiangsu Province; Spine Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China
| | - Hong-Sheng Lin
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong Province, China
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13
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Hou ST. The regulatory and enzymatic functions of CRMPs in neuritogenesis, synaptic plasticity, and gene transcription. Neurochem Int 2020; 139:104795. [PMID: 32652266 DOI: 10.1016/j.neuint.2020.104795] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 06/18/2020] [Accepted: 06/22/2020] [Indexed: 12/13/2022]
Abstract
Collapsin response mediator proteins (CRMPs) are ubiquitously expressed in neurons from worms to humans. A cardinal feature of CRMPs is to mediate growth cone collapse in response to Semaphorin-3A signaling through interactions with cytoskeletal proteins. These are critical regulatory roles that CRMPs play during neuritogenesis and neural network formation. Through post-translational modifications, such as phosphorylation, O-GlcNAcylation, SUMOylation, and proteolytic cleavage, CRMPs participate in synaptic plasticity by modulating NMDA receptors, L- and N-type voltage-gated calcium channels (VGCCs), thus affecting neurotransmitter release. CRMPs also possess histone deacetylase (HDAC) activity, which deacetylates histone H4 during neuronal death. Calcium-dependent proteolytic cleavage of CRMPs results in the truncation of CRMPs, producing a large 54 kD fragment (p54). Translocation of the p54 fragment into the nucleus leads to deacetylation of nuclear histone H4 and de-repression of transcription factor E2F1 expression. Increased expression of E2F1 elevates the expression of genes in cell cycle and death. These new and exciting studies lead to the realization that CRMPs are multifunctional proteins with both regulatory and enzymatic functions. Increasing numbers of studies associate these functions of CRMPs with the development of mental and neurological disorders, such as schizophrenia, Alzheimer's diseases, brain trauma, and stroke. This review focuses on new evidence showing the regulatory and enzymatic functions of CRMPs and highlights recent understandings of CRMPs' roles in neurological diseases.
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Affiliation(s)
- Sheng-Tao Hou
- Brain Research Centre and Department of Biology, Southern University of Science and Technology, 1088 Xueyuan Blvd, Nanshan District, Shenzhen, Guangdong Province, 518055, PR China; Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada.
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14
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Nakamura F, Ohshima T, Goshima Y. Collapsin Response Mediator Proteins: Their Biological Functions and Pathophysiology in Neuronal Development and Regeneration. Front Cell Neurosci 2020; 14:188. [PMID: 32655376 PMCID: PMC7325199 DOI: 10.3389/fncel.2020.00188] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 05/29/2020] [Indexed: 12/19/2022] Open
Abstract
Collapsin response mediator proteins (CRMPs), which consist of five homologous cytosolic proteins, are one of the major phosphoproteins in the developing nervous system. The prominent feature of the CRMP family proteins is a new class of microtubule-associated proteins that play important roles in the whole process of developing the nervous system, such as axon guidance, synapse maturation, cell migration, and even in adult brain function. The CRMP C-terminal region is subjected to posttranslational modifications such as phosphorylation, which, in turn, regulates the interaction between the CRMPs and various kinds of proteins including receptors, ion channels, cytoskeletal proteins, and motor proteins. The gene-knockout of the CRMP family proteins produces different phenotypes, thereby showing distinct roles of all CRMP family proteins. Also, the phenotypic analysis of a non-phosphorylated form of CRMP2-knockin mouse model, and studies of pharmacological responses to CRMP-related drugs suggest that the phosphorylation/dephosphorylation process plays a pivotal role in pathophysiology in neuronal development, regeneration, and neurodegenerative disorders, thus showing CRMPs as promising target molecules for therapeutic intervention.
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Affiliation(s)
- Fumio Nakamura
- Department of Biochemistry, Tokyo Women's Medical University, Tokyo, Japan
| | - Toshio Ohshima
- Department of Life Science and Medical Bio-Science, Waseda University, Tokyo, Japan
| | - Yoshio Goshima
- Department of Molecular Pharmacology and Neurobiology, Yokohama City University Graduate School of Medicine, Yokohama, Japan
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15
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Yu C, Sun X, Li J, Chan SO, Wang L. Analysis of axon divergence at the optic chiasm in nogo-a knockout mice. Neurosci Lett 2020; 731:135109. [PMID: 32492476 DOI: 10.1016/j.neulet.2020.135109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 05/26/2020] [Accepted: 05/29/2020] [Indexed: 10/24/2022]
Abstract
Our earlier studies have shown that the axon growth inhibitory molecule Nogo affects axon routing at the optic chiasm likely through a differential regulation of Nogo receptor on the optic axons. Using isoform specific antibodies, we further showed that Nogo-A was predominantly expressed by retinal ganglion cells and their axons, while Nogo-B was highly localized on the radial glia at the midline of the chiasm, suggesting a role of Nogo-B in regulating turning of uncrossed axons. To further investigate the roles of Nogo-A in axon divergence, we analyzed the routing of axons in the chiasm of Nogo-A knockout mice during the growth of axons across the midline. At E13 to E16, there was no significant difference in the contralateral projection (P = 0.6943 for E13; P = 0.9867 for E14; P = 0.4121 for E15 and P = 0.3402 for E16). The results also showed the absence of Nogo-A did not cause any obvious change to the ipsilateral projection at the optic chiasm, both for the early generated uncrossed axons at E13 and E14 and the late cohorts at E15-E16, when compared with the wild-type mice (P = 0.4788 for E13; P = 0.188 for E14; P = 0.3152 for E15 and P = 0.432 for E16). These findings support that Nogo-A is not the major isoform to guide the axon divergence in the mouse optic chiasm.
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Affiliation(s)
- Chao Yu
- Department of Neurology, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong, China; Medical Examination Center, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong, China.
| | - Xiaobo Sun
- Department of Neurology, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong, China.
| | - Jing Li
- Department of Neurology, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong, China.
| | - Sun-On Chan
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China.
| | - Liqing Wang
- Department of Neurology, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong, China; School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China.
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16
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Jiang T, Zhang G, Liang Y, Cai Z, Liang Z, Lin H, Tan M. PlexinA3 Interacts with CRMP2 to Mediate Sema3A Signalling During Dendritic Growth in Cultured Cerebellar Granule Neurons. Neuroscience 2020; 434:83-92. [DOI: 10.1016/j.neuroscience.2020.02.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 02/05/2020] [Accepted: 02/06/2020] [Indexed: 11/26/2022]
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17
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Rigby MJ, Gomez TM, Puglielli L. Glial Cell-Axonal Growth Cone Interactions in Neurodevelopment and Regeneration. Front Neurosci 2020; 14:203. [PMID: 32210757 PMCID: PMC7076157 DOI: 10.3389/fnins.2020.00203] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 02/24/2020] [Indexed: 12/19/2022] Open
Abstract
The developing nervous system is a complex yet organized system of neurons, glial support cells, and extracellular matrix that arranges into an elegant, highly structured network. The extracellular and intracellular events that guide axons to their target locations have been well characterized in many regions of the developing nervous system. However, despite extensive work, we have a poor understanding of how axonal growth cones interact with surrounding glial cells to regulate network assembly. Glia-to-growth cone communication is either direct through cellular contacts or indirect through modulation of the local microenvironment via the secretion of factors or signaling molecules. Microglia, oligodendrocytes, astrocytes, Schwann cells, neural progenitor cells, and olfactory ensheathing cells have all been demonstrated to directly impact axon growth and guidance. Expanding our understanding of how different glial cell types directly interact with growing axons throughout neurodevelopment will inform basic and clinical neuroscientists. For example, identifying the key cellular players beyond the axonal growth cone itself may provide translational clues to develop therapeutic interventions to modulate neuron growth during development or regeneration following injury. This review will provide an overview of the current knowledge about glial involvement in development of the nervous system, specifically focusing on how glia directly interact with growing and maturing axons to influence neuronal connectivity. This focus will be applied to the clinically-relevant field of regeneration following spinal cord injury, highlighting how a better understanding of the roles of glia in neurodevelopment can inform strategies to improve axon regeneration after injury.
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Affiliation(s)
- Michael J Rigby
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, United States.,Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI, United States.,Waisman Center, University of Wisconsin-Madison, Madison, WI, United States
| | - Timothy M Gomez
- Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI, United States.,Department of Neuroscience, University of Wisconsin-Madison, Madison, WI, United States
| | - Luigi Puglielli
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, United States.,Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI, United States.,Waisman Center, University of Wisconsin-Madison, Madison, WI, United States.,Geriatric Research Education Clinical Center, Veterans Affairs Medical Center, Madison, WI, United States
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18
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Chiha W, Bartlett CA, Petratos S, Fitzgerald M, Harvey AR. Intravitreal application of AAV-BDNF or mutant AAV-CRMP2 protects retinal ganglion cells and stabilizes axons and myelin after partial optic nerve injury. Exp Neurol 2020; 326:113167. [PMID: 31904385 DOI: 10.1016/j.expneurol.2019.113167] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 12/20/2019] [Accepted: 12/31/2019] [Indexed: 12/29/2022]
Abstract
Secondary degeneration following an initial injury to the central nervous system (CNS) results in increased tissue loss and is associated with increasing functional impairment. Unilateral partial dorsal transection of the adult rat optic nerve (ON) has proved to be a useful experimental model in which to study factors that contribute to secondary degenerative events. Using this injury model, we here quantified the protective effects of intravitreally administered bi-cistronic adeno-associated viral (AAV2) vectors encoding either brain derived neurotrophic factor (BDNF) or a mutant, phospho-resistant, version of collapsin response mediator protein 2 (CRMP2T555A) on retinal ganglion cells (RGCs), their axons, and associated myelin. To test for potential synergistic interactions, some animals received combined injections of both vectors. Three months post-injury, all treatments maintained RGC numbers in central retina, but only AAV2-BDNF significantly protected ventrally located RGCs exclusively vulnerable to secondary degeneration. Behaviourally, treatments that involved AAV2-BDNF significantly restored the number of smooth-pursuit phases of optokinetic nystagmus. While all therapeutic regimens preserved axonal density and proportions of typical complexes, including heminodes and single nodes, BDNF treatments were generally more effective in maintaining the length of the node of Ranvier in myelin surrounding ventral ON axons after injury. Both AAV2-BDNF and AAV2-CRMP2T555A prevented injury-induced changes in G-ratio and overall myelin thickness, but only AAV2-BDNF administration protected against large-scale myelin decompaction in ventral ON. In summary, in a model of secondary CNS degeneration, both BDNF and CRMP2T555A vectors were neuroprotective, however different efficacies were observed for these overexpressed proteins in the retina and ON, suggesting disparate cellular and molecular targets driving responses for neural repair. The potential use of these vectors to treat other CNS injuries and pathologies is discussed.
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Affiliation(s)
- Wissam Chiha
- School of Biological Sciences, The University of Western Australia, WA 6009, Australia; Curtin Health Innovation Research Institute, Curtin University, Belmont, WA 6102, Australia
| | - Carole A Bartlett
- School of Biological Sciences, The University of Western Australia, WA 6009, Australia
| | - Steven Petratos
- Department of Neuroscience, Monash University, VIC 3004, Australia
| | - Melinda Fitzgerald
- Perron Institute for Neurological and Translational Science, Nedlands, WA 6009, Australia; Curtin Health Innovation Research Institute, Curtin University, Belmont, WA 6102, Australia
| | - Alan R Harvey
- School of Human Sciences, The University of Western Australia, WA 6009, Australia; Perron Institute for Neurological and Translational Science, Nedlands, WA 6009, Australia.
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19
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Laredo F, Plebanski J, Tedeschi A. Pericytes: Problems and Promises for CNS Repair. Front Cell Neurosci 2019; 13:546. [PMID: 31866833 PMCID: PMC6908836 DOI: 10.3389/fncel.2019.00546] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 11/25/2019] [Indexed: 12/14/2022] Open
Abstract
Microvascular complications are often associated with slow and progressive damage of various organs. Pericytes are multi-functional mural cells of the microcirculation that control blood flow, vascular permeability and homeostasis. Whereas accumulating evidence suggests that these cells are also implicated in a variety of diseases, pericytes represent promising targets that can be manipulated for therapeutic gain. Here, we review the role of pericytes in angiogenesis, blood-brain barrier (BBB) function, neuroinflammation, tissue fibrosis, axon regeneration failure, and neurodegeneration. In addition, we outline strategies altering pericyte behavior to point out problems and promises for axon regeneration and central nervous system (CNS) repair following injury or disease.
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Affiliation(s)
- Fabio Laredo
- Department of Neuroscience, Wexner Medical Center, The Ohio State University, Columbus, OH, United States.,Department of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Julia Plebanski
- Department of Neuroscience, Wexner Medical Center, The Ohio State University, Columbus, OH, United States
| | - Andrea Tedeschi
- Department of Neuroscience, Wexner Medical Center, The Ohio State University, Columbus, OH, United States.,Discovery Theme on Chronic Brain Injury, The Ohio State University, Columbus, OH, United States
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20
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Sekine Y, Lindborg JA, Strittmatter SM. A proteolytic C-terminal fragment of Nogo-A (reticulon-4A) is released in exosomes and potently inhibits axon regeneration. J Biol Chem 2019; 295:2175-2183. [PMID: 31748413 DOI: 10.1074/jbc.ra119.009896] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 11/14/2019] [Indexed: 11/06/2022] Open
Abstract
Glial signals are known to inhibit axonal regeneration and functional recovery after mammalian central nervous system trauma, including spinal cord injury. Such signals include membrane-associated proteins of the oligodendrocyte plasma membrane and astrocyte-derived, matrix-associated proteins. Here, using cell lines and primary cortical neuron cultures, recombinant protein expression, immunoprecipitation and immunoblot assays, transmission EM of exosomes, and axon regeneration assays, we explored the secretion and activity of the myelin-associated neurite outgrowth inhibitor Nogo-A and observed exosomal release of a 24-kDa C-terminal Nogo-A fragment from cultured cells. We found that the cleavage site in this 1192-amino-acid-long fragment is located between amino acids 961-971. We also detected a Nogo-66 receptor (NgR1)-interacting Nogo-66 domain on the exosome surface. Enzyme inhibitor treatment and siRNA knockdown revealed that β-secretase 1 (BACE1) is the protease responsible for Nogo-A cleavage. Functionally, exosomes with the Nogo-66 domain on their surface potently inhibited axonal regeneration of mechanically injured cerebral cortex neurons from mice. Production of this fragment was observed in the exosomal fraction from neuronal tissue lysates after spinal cord crush injury of mice. We also noted that, relative to the exosomal marker Alix, a Nogo-immunoreactive, 24-kDa protein is enriched in exosomes 2-fold after injury. We conclude that membrane-associated Nogo-A produced in oligodendrocytes is processed proteolytically by BACE1, is released via exosomes, and is a potent diffusible inhibitor of regenerative growth in NgR1-expressing axons.
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Affiliation(s)
- Yuichi Sekine
- Cellular Neuroscience, Neurodegeneration, and Repair Program, Departments of Neurology and of Neuroscience, Yale University School of Medicine, New Haven, Connecticut 06536
| | - Jane A Lindborg
- Cellular Neuroscience, Neurodegeneration, and Repair Program, Departments of Neurology and of Neuroscience, Yale University School of Medicine, New Haven, Connecticut 06536
| | - Stephen M Strittmatter
- Cellular Neuroscience, Neurodegeneration, and Repair Program, Departments of Neurology and of Neuroscience, Yale University School of Medicine, New Haven, Connecticut 06536.
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