201
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Progress and perspectives of neural tissue engineering. Front Med 2015; 9:401-11. [DOI: 10.1007/s11684-015-0415-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 07/06/2015] [Indexed: 10/22/2022]
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202
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DePaul MA, Lin CY, Silver J, Lee YS. Peripheral Nerve Transplantation Combined with Acidic Fibroblast Growth Factor and Chondroitinase Induces Regeneration and Improves Urinary Function in Complete Spinal Cord Transected Adult Mice. PLoS One 2015; 10:e0139335. [PMID: 26426529 PMCID: PMC4591338 DOI: 10.1371/journal.pone.0139335] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 09/11/2015] [Indexed: 01/08/2023] Open
Abstract
The loss of lower urinary tract (LUT) control is a ubiquitous consequence of a complete spinal cord injury, attributed to a lack of regeneration of supraspinal pathways controlling the bladder. Previous work in our lab has utilized a combinatorial therapy of peripheral nerve autografts (PNG), acidic fibroblast growth factor (aFGF), and chondroitinase ABC (ChABC) to treat a complete T8 spinal cord transection in the adult rat, resulting in supraspinal control of bladder function. In the present study we extended these findings by examining the use of the combinatorial PNG+aFGF+ChABC treatment in a T8 transected mouse model, which more closely models human urinary deficits following spinal cord injury. Cystometry analysis and external urethral sphincter electromyograms reveal that treatment with PNG+aFGF+ChABC reduced bladder weight, improved bladder and external urethral sphincter histology, and significantly enhanced LUT function, resulting in more efficient voiding. Treated mice's injured spinal cord also showed a reduction in collagen scaring, and regeneration of serotonergic and tyrosine hydroxylase-positive axons across the lesion and into the distal spinal cord. Regeneration of serotonin axons correlated with LUT recovery. These results suggest that our mouse model of LUT dysfunction recapitulates the results found in the rat model and may be used to further investigate genetic contributions to regeneration failure.
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Affiliation(s)
- Marc A. DePaul
- Department of Neurosciences, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Ching-Yi Lin
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
| | - Jerry Silver
- Department of Neurosciences, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Yu-Shang Lee
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, United States of America
- * E-mail:
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203
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Siebert JR, Eade AM, Osterhout DJ. Biomaterial Approaches to Enhancing Neurorestoration after Spinal Cord Injury: Strategies for Overcoming Inherent Biological Obstacles. BIOMED RESEARCH INTERNATIONAL 2015; 2015:752572. [PMID: 26491685 PMCID: PMC4600545 DOI: 10.1155/2015/752572] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Accepted: 07/22/2015] [Indexed: 01/14/2023]
Abstract
While advances in technology and medicine have improved both longevity and quality of life in patients living with a spinal cord injury, restoration of full motor function is not often achieved. This is due to the failure of repair and regeneration of neuronal connections in the spinal cord after injury. In this review, the complicated nature of spinal cord injury is described, noting the numerous cellular and molecular events that occur in the central nervous system following a traumatic lesion. In short, postinjury tissue changes create a complex and dynamic environment that is highly inhibitory to the process of neural regeneration. Strategies for repair are outlined with a particular focus on the important role of biomaterials in designing a therapeutic treatment that can overcome this inhibitory environment. The importance of considering the inherent biological response of the central nervous system to both injury and subsequent therapeutic interventions is highlighted as a key consideration for all attempts at improving functional recovery.
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Affiliation(s)
- Justin R. Siebert
- Lake Erie College of Osteopathic Medicine at Seton Hill, Greensburg, PA 15601, USA
| | - Amber M. Eade
- Lake Erie College of Osteopathic Medicine at Seton Hill, Greensburg, PA 15601, USA
| | - Donna J. Osterhout
- Department of Cell and Developmental Biology, State University of New York Upstate Medical University, Syracuse, NY 13210, USA
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204
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McKerracher L, Rosen KM. MAG, myelin and overcoming growth inhibition in the CNS. Front Mol Neurosci 2015; 8:51. [PMID: 26441514 PMCID: PMC4561339 DOI: 10.3389/fnmol.2015.00051] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 08/25/2015] [Indexed: 01/22/2023] Open
Abstract
While neurons in the central nervous system (CNS) have the capacity to regenerate their axons after injury, they fail to do so, in part because regeneration is limited by growth inhibitory proteins present in CNS myelin. Myelin-associated glycoprotein (MAG) was the first myelin-derived growth inhibitory protein identified, and its inhibitory activity was initially elucidated in 1994 independently by the Filbin lab and the McKerracher lab using cell-based and biochemical techniques, respectively. Since that time we have gained a wealth of knowledge concerning the numerous growth inhibitory proteins that are present in myelin, and we also have dissected many of the neuronal signaling pathways that act as stop signs for axon regeneration. Here we give an overview of the early research efforts that led to the identification of myelin-derived growth inhibitory proteins, and the importance of this family of proteins for understanding neurotrauma and CNS diseases. We further provide an update on how this knowledge has been translated towards current clinical studies in regenerative medicine.
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Affiliation(s)
- Lisa McKerracher
- BioAxone BioSciences Inc.Cambridge, MA, USA
- Department of Neurology and Neurosurgery, McGill UniversityMontreal, QC, Canada
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205
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Peng WS, Qi C, Zhang H, Gao ML, Wang H, Ren F, Li XQ. Distribution of paired immunoglobulin-like receptor B in the nervous system related to regeneration difficulties after unilateral lumbar spinal cord injury. Neural Regen Res 2015; 10:1139-46. [PMID: 26330840 PMCID: PMC4541248 DOI: 10.4103/1673-5374.160111] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/10/2015] [Indexed: 12/21/2022] Open
Abstract
Paired immunoglobulin-like receptor B (PirB) is a functional receptor of myelin-associated inhibitors for axonal regeneration and synaptic plasticity in the central nervous system, and thus suppresses nerve regeneration. The regulatory effect of PirB on injured nerves has received a lot of attention. To better understand nerve regeneration inability after spinal cord injury, this study aimed to investigate the distribution of PirB (via immunofluorescence) in the central nervous system and peripheral nervous system 10 days after injury. Immunoreactivity for PirB increased in the dorsal root ganglia, sciatic nerves, and spinal cord segments. In the dorsal root ganglia and sciatic nerves, PirB was mainly distributed along neuronal and axonal membranes. PirB was found to exhibit a diffuse, intricate distribution in the dorsal and ventral regions. Immunoreactivity for PirB was enhanced in some cortical neurons located in the bilateral precentral gyri. Overall, the findings suggest a pattern of PirB immunoreactivity in the nervous system after unilateral spinal transection injury, and also indicate that PirB may suppress repair after injury.
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Affiliation(s)
- Wan-Shu Peng
- Department of Pathophysiology, Shanxi Medical University, Taiyuan, Shanxi Province, China
| | - Chao Qi
- Department of Pathophysiology, Shanxi Medical University, Taiyuan, Shanxi Province, China
| | - Hong Zhang
- Department of Pathophysiology, Shanxi Medical University, Taiyuan, Shanxi Province, China
| | - Mei-Ling Gao
- Department of Pathophysiology, Shanxi Medical University, Taiyuan, Shanxi Province, China
| | - Hong Wang
- Department of Pathophysiology, Shanxi Medical University, Taiyuan, Shanxi Province, China
| | - Fei Ren
- Department of Pathophysiology, Shanxi Medical University, Taiyuan, Shanxi Province, China
| | - Xia-Qing Li
- Department of Pathophysiology, Shanxi Medical University, Taiyuan, Shanxi Province, China
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206
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Tso D, McKinnon RD. Cell replacement therapy for central nervous system diseases. Neural Regen Res 2015; 10:1356-8. [PMID: 26604878 PMCID: PMC4625483 DOI: 10.4103/1673-5374.165209] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/19/2015] [Indexed: 12/11/2022] Open
Abstract
The brain and spinal cord can not replace neurons or supporting glia that are lost through traumatic injury or disease. In pre-clinical studies, however, neural stem and progenitor cell transplants can promote functional recovery. Thus the central nervous system is repair competent but lacks endogenous stem cell resources. To make transplants clinically feasible, this field needs a source of histocompatible, ethically acceptable and non-tumorgenic cells. One strategy to generate patient-specific replacement cells is to reprogram autologous cells such as fibroblasts into pluripotent stem cells which can then be differentiated into the required cell grafts. However, the utility of pluripotent cell derived grafts is limited since they can retain founder cells with intrinsic neoplastic potential. A recent extension of this technology directly reprograms fibroblasts into the final graftable cells without an induced pluripotent stem cell intermediate, avoiding the pluripotent caveat. For both types of reprogramming the conversion efficiency is very low resulting in the need to amplify the cells in culture which can lead to chromosomal instability and neoplasia. Thus to make reprogramming biology clinically feasible, we must improve the efficiency. The ultimate source of replacement cells may reside in directly reprogramming accessible cells within the brain.
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Affiliation(s)
- Danju Tso
- Department of Surgery (Neurosurgery), Rutgers-Robert Wood Johnson Medical School, New Brunswick, NJ, USA
| | - Randall D. McKinnon
- Department of Surgery (Neurosurgery), Rutgers-Robert Wood Johnson Medical School, New Brunswick, NJ, USA
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207
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Ma TC, Willis DE. What makes a RAG regeneration associated? Front Mol Neurosci 2015; 8:43. [PMID: 26300725 PMCID: PMC4528284 DOI: 10.3389/fnmol.2015.00043] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 07/24/2015] [Indexed: 12/31/2022] Open
Abstract
Regenerative failure remains a significant barrier for functional recovery after central nervous system (CNS) injury. As such, understanding the physiological processes that regulate axon regeneration is a central focus of regenerative medicine. Studying the gene transcription responses to axon injury of regeneration competent neurons, such as those of the peripheral nervous system (PNS), has provided insight into the genes associated with regeneration. Though several individual “regeneration-associated genes” (RAGs) have been identified from these studies, the response to injury likely regulates the expression of functionally coordinated and complementary gene groups. For instance, successful regeneration would require the induction of genes that drive the intrinsic growth capacity of neurons, while simultaneously downregulating the genes that convey environmental inhibitory cues. Thus, this view emphasizes the transcriptional regulation of gene “programs” that contribute to the overall goal of axonal regeneration. Here, we review the known RAGs, focusing on how their transcriptional regulation can reveal the underlying gene programs that drive a regenerative phenotype. Finally, we will discuss paradigms under which we can determine whether these genes are injury-associated, or indeed necessary for regeneration.
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Affiliation(s)
- Thong C Ma
- Department of Neurology, Columbia University New York, NY, USA
| | - Dianna E Willis
- Brain Mind Research Institute, Weill Cornell Medical College New York, NY, USA ; Burke-Cornell Medical Research Institute White Plains, NY, USA
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208
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Li Z, He Y, Fan S, Sun B. Clemastine rescues behavioral changes and enhances remyelination in the cuprizone mouse model of demyelination. Neurosci Bull 2015; 31:617-25. [PMID: 26253956 DOI: 10.1007/s12264-015-1555-3] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 06/10/2015] [Indexed: 12/18/2022] Open
Abstract
Increasing evidence suggests that white matter disorders based on myelin sheath impairment may underlie the neuropathological changes in schizophrenia. But it is unknown whether enhancing remyelination is a beneficial approach to schizophrenia. To investigate this hypothesis, we used clemastine, an FDA-approved drug with high potency in promoting oligodendroglial differentiation and myelination, on a cuprizone-induced mouse model of demyelination. The mice exposed to cuprizone (0.2% in chow) for 6 weeks displayed schizophrenia-like behavioral changes, including decreased exploration of the center in the open field test and increased entries into the arms of the Y-maze, as well as evident demyelination in the cortex and corpus callosum. Clemastine treatment was initiated upon cuprizone withdrawal at 10 mg/kg per day for 3 weeks. As expected, myelin repair was greatly enhanced in the demyelinated regions with increased mature oligodendrocytes (APC-positive) and myelin basic protein. More importantly, the clemastine treatment rescued the schizophrenia-like behavioral changes in the open field test and the Y-maze compared to vehicle, suggesting a beneficial effect via promoting myelin repair. Our findings indicate that enhancing remyelination may be a potential therapy for schizophrenia.
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Affiliation(s)
- Zhifang Li
- Department of Neurology, Affiliated Hospital of Academy of Military Medical Sciences, Beijing, 100071, China.
| | - Yangtao He
- Department of Histology and Embryology, Chongqing Key Laboratory of Neurobiology, Third Military Medical University, Chongqing, 400038, China.
| | - Shuangyi Fan
- Department of Neurology, Affiliated Hospital of Academy of Military Medical Sciences, Beijing, 100071, China
| | - Binbin Sun
- Department of Neurology, Affiliated Hospital of Academy of Military Medical Sciences, Beijing, 100071, China
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209
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Zhai P, Chen XB, Schreyer DJ. An in vitro study of peptide-loaded alginate nanospheres for antagonizing the inhibitory effect of Nogo-A protein on axonal growth. ACTA ACUST UNITED AC 2015; 10:045016. [PMID: 26238410 DOI: 10.1088/1748-6041/10/4/045016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The adult mammalian central nervous system has limited ability to regenerate after injury. This is due, in part, to the presence of myelin-associated axon growth inhibitory proteins such as Nogo-A that bind and activate the Nogo receptor, leading to profound inhibition of actin-based motility within the growing axon tip. This paper presents an in vitro study of the use of a Nogo receptor-blocking peptide to antagonize the inhibitory effect of Nogo-A on axon growth. Alginate nanospheres were fabricated using an emulsion technique and loaded with Nogo receptor-blocking peptide, or with other model proteins. Protein release profiles were studied, and retention of the bioactivity of released proteins was verified. Primary dorsal root ganglion neurons were cultured and their ability to grow neurites was challenged with Nogo-A chimeric protein in the absence or presence of Nogo receptor antagonist peptide-loaded alginate nanospheres. Our results demonstrate that peptide released from alginate nanospheres could overcome the growth inhibitory effect of Nogo-A, suggesting that a similar peptide delivery strategy using alginate nanospheres might be used to improve axon regeneration within the injured central nervous system.
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Affiliation(s)
- Peng Zhai
- Division of Biomedical Engineering, University of Saskatchewan, Saskatoon SK S7N 5A9, Canada
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210
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Falcón-Urrutia P, Carrasco CM, Lois P, Palma V, Roth AD. Shh Signaling through the Primary Cilium Modulates Rat Oligodendrocyte Differentiation. PLoS One 2015. [PMID: 26218245 PMCID: PMC4517900 DOI: 10.1371/journal.pone.0133567] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Primary Cilia (PC) are a very likely place for signal integration where multiple signaling pathways converge. Two major signaling pathways clearly shown to signal through the PC, Sonic Hedgehog (Shh) and PDGF-Rα, are particularly important for the proliferation and differentiation of oligodendrocytes, suggesting that their interaction occurs in or around this organelle. We identified PC in rat oligodendrocyte precursor cells (OPCs) and found that, while easily detectable in early OPCs, PC are lost as these cells progress to terminal differentiation. We confirmed the interaction between these pathways, as cyclopamine inhibition of Hedgehog function impairs both PDGF-mediated OPC proliferation and Shh-dependent cell branching. However, we failed to detect PDGF-Rα localization into the PC. Remarkably, ciliobrevin-mediated disruption of PC and reduction of OPC process extension was counteracted by recombinant Shh treatment, while PDGF had no effect. Therefore, while PDGF-Rα-dependent OPC proliferation and survival most probably does not initiate at the PC, still the integrity of this organelle and cilium-centered pathway is necessary for OPC survival and differentiation.
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Affiliation(s)
- Paulina Falcón-Urrutia
- Department of Biology, Faculty of Science, Universidad de Chile, Santiago, Chile
- FONDAP Center for Genome Regulation, Santiago, Chile
| | - Carlos M. Carrasco
- Department of Biology, Faculty of Science, Universidad de Chile, Santiago, Chile
| | - Pablo Lois
- Department of Biology, Faculty of Science, Universidad de Chile, Santiago, Chile
- FONDAP Center for Genome Regulation, Santiago, Chile
| | - Veronica Palma
- Department of Biology, Faculty of Science, Universidad de Chile, Santiago, Chile
- FONDAP Center for Genome Regulation, Santiago, Chile
- * E-mail: (AR); (VP)
| | - Alejandro D. Roth
- Department of Biology, Faculty of Science, Universidad de Chile, Santiago, Chile
- * E-mail: (AR); (VP)
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211
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Thiede-Stan NK, Schwab ME. Attractive and repulsive factors act through multi-subunit receptor complexes to regulate nerve fiber growth. J Cell Sci 2015; 128:2403-14. [PMID: 26116576 DOI: 10.1242/jcs.165555] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In the nervous system, attractive and repulsive factors guide neuronal growth, pathfinding and target innervation during development, learning and regeneration after injury. Repulsive and growth-inhibitory factors, such as some ephrins, semaphorins, netrins and myelin-associated growth inhibitors, restrict nerve fiber growth, whereas neurotrophins, and other ephrins, semaphorins and netrins attract fibers and promote neurite growth. Several of these guidance molecules also play crucial roles in vasculogenesis, and regulate cell migration and tissue formation in different organs. Precise and highly specific signal transduction in space and time is required in all these cases, which primarily depends on the presence and function of specific receptors. Interestingly, many of these ligands act through multi-subunit receptor complexes. In this Commentary, we review the current knowledge of how complexes of the receptors for attractive and repulsive neurite growth regulatory factors are reorganized in a spatial and temporal manner, and reveal the implications that such dynamics have on the signaling events that coordinate neurite fiber growth.
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Affiliation(s)
- Nina K Thiede-Stan
- Brain Research Institute, University of Zurich, Department of Health Sciences & Technology, ETH Zurich, Zurich 8057, Switzerland
| | - Martin E Schwab
- Brain Research Institute, University of Zurich, Department of Health Sciences & Technology, ETH Zurich, Zurich 8057, Switzerland
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212
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Abstract
Myelination of axons in the nervous system of vertebrates enables fast, saltatory impulse propagation, one of the best-understood concepts in neurophysiology. However, it took a long while to recognize the mechanistic complexity both of myelination by oligodendrocytes and Schwann cells and of their cellular interactions. In this review, we highlight recent advances in our understanding of myelin biogenesis, its lifelong plasticity, and the reciprocal interactions of myelinating glia with the axons they ensheath. In the central nervous system, myelination is also stimulated by axonal activity and astrocytes, whereas myelin clearance involves microglia/macrophages. Once myelinated, the long-term integrity of axons depends on glial supply of metabolites and neurotrophic factors. The relevance of this axoglial symbiosis is illustrated in normal brain aging and human myelin diseases, which can be studied in corresponding mouse models. Thus, myelinating cells serve a key role in preserving the connectivity and functions of a healthy nervous system.
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Affiliation(s)
- Klaus-Armin Nave
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, D-37075 Göttingen, Germany; ,
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213
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Cells transplanted onto the surface of the glial scar reveal hidden potential for functional neural regeneration. Proc Natl Acad Sci U S A 2015; 112:E3431-40. [PMID: 26080415 DOI: 10.1073/pnas.1501835112] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cell transplantation therapy has long been investigated as a therapeutic intervention for neurodegenerative disorders, including spinal cord injury, Parkinson's disease, and amyotrophic lateral sclerosis. Indeed, patients have high hopes for a cell-based therapy. However, there are numerous practical challenges for clinical translation. One major problem is that only very low numbers of donor cells survive and achieve functional integration into the host. Glial scar tissue in chronic neurodegenerative disorders strongly inhibits regeneration, and this inhibition must be overcome to accomplish successful cell transplantation. Intraneural cell transplantation is considered to be the best way to deliver cells to the host. We questioned this view with experiments in vivo on a rat glial scar model of the auditory system. Our results show that intraneural transplantation to the auditory nerve, preceded by chondroitinase ABC (ChABC)-treatment, is ineffective. There is no functional recovery, and almost all transplanted cells die within a few weeks. However, when donor cells are placed on the surface of a ChABC-treated gliotic auditory nerve, they autonomously migrate into it and recapitulate glia- and neuron-guided cell migration modes to repair the auditory pathway and recover auditory function. Surface transplantation may thus pave the way for improved functional integration of donor cells into host tissue, providing a less invasive approach to rescue clinically important neural tracts.
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214
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Li L, Deng B, Wang S, Zhong H, Liu Z, Jin W, Jiang T, Xiao Z, Wang Q. Asynchronous therapy targeting Nogo-A enhances neurobehavioral recovery by reducing neuronal loss and promoting neurite outgrowth after cerebral ischemia in mice. J Drug Target 2015; 24:13-23. [PMID: 26061295 DOI: 10.3109/1061186x.2015.1052070] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Therapeutics targeting the Nogo-A signal pathway hold promise to promote recovery following brain injury. Based on the temporal characteristics of Nogo-A expression in the process of cerebral ischemia and reperfusion, we tested a novel asynchronous treatment, in which TAT-M9 was used in the early stage to decrease neuronal loss, and TAT-NEP1-40 was used in the delayed stage to promote neurite outgrowth after bilateral common carotid artery occlusion (BCCAO) in mice. Both TAT-M9 and TAT-NEP1-40 were efficiently delivered into the brains of mice by intraperitoneal injection. TAT-M9 treatment promoted neuron survival and inhibited neuronal apoptosis. Asynchronous therapy with TAT-M9 and TAT-NEP1-40 increased the expression of Tau, GAP43 and MAP-2 proteins, and enhanced short-term and long-term cognitive functions. In conclusion, the asynchronous treatment had a long-term neuroprotective effect, which reduced neurologic injury and apoptosis, promoted neurite outgrowth and enhanced functional recovery after ischemia. It suggests that this asynchronous treatment could be a promising therapy for cerebral ischemia in humans.
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Affiliation(s)
- Liya Li
- a Department of Anesthesiology , Xijing Hospital, Fourth Military Medical University , Xi' an , China .,b Department of Emergency , The Second Affiliated Hospital of Dalian Medical University , Dalian , China
| | - Bin Deng
- c Department of Anesthesiology , State Key Laboratory of Military Stomatology, School of Stomatology, Fourth Military Medical University , Xi'an , China , and
| | - Shiquan Wang
- a Department of Anesthesiology , Xijing Hospital, Fourth Military Medical University , Xi' an , China
| | - Haixing Zhong
- a Department of Anesthesiology , Xijing Hospital, Fourth Military Medical University , Xi' an , China
| | - Zhaoyu Liu
- a Department of Anesthesiology , Xijing Hospital, Fourth Military Medical University , Xi' an , China
| | - Weilin Jin
- d Institute of Neurosciences, School of Life Sciences and Biotechnology, Jiao Tong University , Shanghai , China
| | - Tao Jiang
- a Department of Anesthesiology , Xijing Hospital, Fourth Military Medical University , Xi' an , China
| | - Zhaoyang Xiao
- b Department of Emergency , The Second Affiliated Hospital of Dalian Medical University , Dalian , China
| | - Qiang Wang
- a Department of Anesthesiology , Xijing Hospital, Fourth Military Medical University , Xi' an , China
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215
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Integration of donor mesenchymal stem cell-derived neuron-like cells into host neural network after rat spinal cord transection. Biomaterials 2015; 53:184-201. [DOI: 10.1016/j.biomaterials.2015.02.073] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 02/08/2015] [Accepted: 02/15/2015] [Indexed: 12/27/2022]
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216
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Robust Axonal Regeneration Occurs in the Injured CAST/Ei Mouse CNS. Neuron 2015; 86:1215-27. [PMID: 26004914 DOI: 10.1016/j.neuron.2015.05.005] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 03/11/2015] [Accepted: 04/24/2015] [Indexed: 12/16/2022]
Abstract
Axon regeneration in the CNS requires reactivating injured neurons' intrinsic growth state and enabling growth in an inhibitory environment. Using an inbred mouse neuronal phenotypic screen, we find that CAST/Ei mouse adult dorsal root ganglion neurons extend axons more on CNS myelin than the other eight strains tested, especially when pre-injured. Injury-primed CAST/Ei neurons also regenerate markedly in the spinal cord and optic nerve more than those from C57BL/6 mice and show greater sprouting following ischemic stroke. Heritability estimates indicate that extended growth in CAST/Ei neurons on myelin is genetically determined, and two whole-genome expression screens yield the Activin transcript Inhba as most correlated with this ability. Inhibition of Activin signaling in CAST/Ei mice diminishes their CNS regenerative capacity, whereas its activation in C57BL/6 animals boosts regeneration. This screen demonstrates that mammalian CNS regeneration can occur and reveals a molecular pathway that contributes to this ability.
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217
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Siddiq MM, Hannila SS, Carmel JB, Bryson JB, Hou J, Nikulina E, Willis MR, Mellado W, Richman EL, Hilaire M, Hart RP, Filbin MT. Metallothionein-I/II Promotes Axonal Regeneration in the Central Nervous System. J Biol Chem 2015; 290:16343-56. [PMID: 25947372 DOI: 10.1074/jbc.m114.630574] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Indexed: 11/06/2022] Open
Abstract
The adult CNS does not spontaneously regenerate after injury, due in large part to myelin-associated inhibitors such as myelin-associated glycoprotein (MAG), Nogo-A, and oligodendrocyte-myelin glycoprotein. All three inhibitors can interact with either the Nogo receptor complex or paired immunoglobulin-like receptor B. A conditioning lesion of the sciatic nerve allows the central processes of dorsal root ganglion (DRG) neurons to spontaneously regenerate in vivo after a dorsal column lesion. After a conditioning lesion, DRG neurons are no longer inhibited by myelin, and this effect is cyclic AMP (cAMP)- and transcription-dependent. Using a microarray analysis, we identified several genes that are up-regulated both in adult DRGs after a conditioning lesion and in DRG neurons treated with cAMP analogues. One gene that was up-regulated under both conditions is metallothionein (MT)-I. We show here that treatment with two closely related isoforms of MT (MT-I/II) can overcome the inhibitory effects of both myelin and MAG for cortical, hippocampal, and DRG neurons. Intrathecal delivery of MT-I/II to adult DRGs also promotes neurite outgrowth in the presence of MAG. Adult DRGs from MT-I/II-deficient mice extend significantly shorter processes on MAG compared with wild-type DRG neurons, and regeneration of dorsal column axons does not occur after a conditioning lesion in MT-I/II-deficient mice. Furthermore, a single intravitreal injection of MT-I/II after optic nerve crush promotes axonal regeneration. Mechanistically, MT-I/II ability to overcome MAG-mediated inhibition is transcription-dependent, and MT-I/II can block the proteolytic activity of α-secretase and the activation of PKC and Rho in response to soluble MAG.
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Affiliation(s)
- Mustafa M Siddiq
- From the Department of Biological Sciences, Hunter College, City University of New York, New York 10065 and
| | - Sari S Hannila
- From the Department of Biological Sciences, Hunter College, City University of New York, New York 10065 and
| | - Jason B Carmel
- the W. M. Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, New Jersey 08854
| | - John B Bryson
- From the Department of Biological Sciences, Hunter College, City University of New York, New York 10065 and
| | - Jianwei Hou
- From the Department of Biological Sciences, Hunter College, City University of New York, New York 10065 and
| | - Elena Nikulina
- From the Department of Biological Sciences, Hunter College, City University of New York, New York 10065 and
| | - Matthew R Willis
- From the Department of Biological Sciences, Hunter College, City University of New York, New York 10065 and
| | - Wilfredo Mellado
- From the Department of Biological Sciences, Hunter College, City University of New York, New York 10065 and
| | - Erica L Richman
- From the Department of Biological Sciences, Hunter College, City University of New York, New York 10065 and
| | - Melissa Hilaire
- From the Department of Biological Sciences, Hunter College, City University of New York, New York 10065 and
| | - Ronald P Hart
- the W. M. Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, New Jersey 08854
| | - Marie T Filbin
- From the Department of Biological Sciences, Hunter College, City University of New York, New York 10065 and
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218
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Belin S, Nawabi H, Wang C, Tang S, Latremoliere A, Warren P, Schorle H, Uncu C, Woolf CJ, He Z, Steen JA. Injury-induced decline of intrinsic regenerative ability revealed by quantitative proteomics. Neuron 2015; 86:1000-1014. [PMID: 25937169 DOI: 10.1016/j.neuron.2015.03.060] [Citation(s) in RCA: 171] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Revised: 11/21/2014] [Accepted: 03/20/2015] [Indexed: 12/28/2022]
Abstract
Neurons differ in their responses to injury, but the underlying mechanisms remain poorly understood. Using quantitative proteomics, we characterized the injury-triggered response from purified intact and axotomized retinal ganglion cells (RGCs). Subsequent informatics analyses revealed a network of injury-response signaling hubs. In addition to confirming known players, such as mTOR, this also identified new candidates, such as c-myc, NFκB, and Huntingtin. Similar to mTOR, c-myc has been implicated as a key regulator of anabolic metabolism and is downregulated by axotomy. Forced expression of c-myc in RGCs, either before or after injury, promotes dramatic RGC survival and axon regeneration after optic nerve injury. Finally, in contrast to RGCs, neither c-myc nor mTOR was downregulated in injured peripheral sensory neurons. Our studies suggest that c-myc and other injury-responsive pathways are critical to the intrinsic regenerative mechanisms and might represent a novel target for developing neural repair strategies in adults.
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Affiliation(s)
- Stephane Belin
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, and Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Homaira Nawabi
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, and Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Chen Wang
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, and Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Shaojun Tang
- Department of Pathology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Alban Latremoliere
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, and Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Peter Warren
- Department of Urology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Hubert Schorle
- Department of Developmental Pathology, University of Bonn Medical School, Sigmund Freud Strasse 25, 53127 Bonn, Germany
| | - Ceren Uncu
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, and Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Clifford J Woolf
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, and Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Zhigang He
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, and Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.
| | - Judith A Steen
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, and Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.
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219
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Watzlawik JO, Kahoud RJ, Ng S, Painter MM, Papke LM, Zoecklein L, Wootla B, Warrington AE, Carey WA, Rodriguez M. Polysialic acid as an antigen for monoclonal antibody HIgM12 to treat multiple sclerosis and other neurodegenerative disorders. J Neurochem 2015; 134:865-78. [PMID: 25866077 DOI: 10.1111/jnc.13121] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 03/27/2015] [Accepted: 04/07/2015] [Indexed: 01/15/2023]
Abstract
CNS regeneration is a desirable goal for diseases of brain and spinal cord. Current therapeutic strategies for the treatment of multiple sclerosis (MS) aim to eliminate detrimental effects of the immune system, so far without reversing disability or affecting long-term prognosis in patients. Approachable molecular targets that stimulate CNS repair are not part of the clinical praxis or have not been identified yet. The purpose of this study was to identify the molecular target of the human monoclonal antibody HIgM12. HIgM12 reverses motor deficits in chronically demyelinated mice, a model of MS. Here, we identified polysialic acid (PSA) attached to the neural cell adhesion molecule (NCAM) as the antigen for HIgM12 by using different NCAM knockout strains and through PSA removal from the NCAM protein core. Antibody binding to CNS tissue and primary cells, antibody-mediated cell adhesion, and neurite outgrowth on HIgM12-coated nitrocellulose was detected only in the presence of PSA as assessed by western blotting, immunoprecipitation, immunocytochemistry, and histochemistry. We conclude that HIgM12 mediates its in vivo and in vitro effects through binding to PSA and has the potential to be an effective therapy for MS and neurodegenerative diseases. The human antibody HIgM12 stimulates neurite outgrowth in vitro and promotes function in chronically demyelinated mice, a model of multiple sclerosis. The cellular antigen for HIgM12 was undetermined. Here, we identified polysialic acid attached to NCAM (neural cell adhesion molecule) as the cellular target for HIgM12. This includes glial fibrillary acidic protein (GFAP)-positive mouse astrocytes (GFAP, red; HIgM12, green; DAPI, blue) among other cell types of the central nervous system. These findings indicate a new strategy for the treatment of neuro-motor disorders including multiple sclerosis.
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Affiliation(s)
- Jens O Watzlawik
- Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Robert J Kahoud
- Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.,Department of Pediatric and Adolescent Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Shermayne Ng
- Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Meghan M Painter
- Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Louisa M Papke
- Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Laurie Zoecklein
- Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Bharath Wootla
- Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Arthur E Warrington
- Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - William A Carey
- Department of Pediatric and Adolescent Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Moses Rodriguez
- Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
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220
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Mietto BS, Mostacada K, Martinez AMB. Neurotrauma and inflammation: CNS and PNS responses. Mediators Inflamm 2015; 2015:251204. [PMID: 25918475 PMCID: PMC4397002 DOI: 10.1155/2015/251204] [Citation(s) in RCA: 124] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 02/24/2015] [Accepted: 03/09/2015] [Indexed: 01/09/2023] Open
Abstract
Traumatic injury to the central nervous system (CNS) or the peripheral nervous system (PNS) triggers a cascade of events which culminate in a robust inflammatory reaction. The role played by inflammation in the course of degeneration and regeneration is not completely elucidated. While, in peripheral nerves, the inflammatory response is assumed to be essential for normal progression of Wallerian degeneration and regeneration, CNS trauma inflammation is often associated with poor recovery. In this review, we discuss key mechanisms that trigger the inflammatory reaction after nervous system trauma, emphasizing how inflammations in both CNS and PNS differ from each other, in terms of magnitude, cell types involved, and effector molecules. Knowledge of the precise mechanisms that elicit and maintain inflammation after CNS and PNS tissue trauma and their effect on axon degeneration and regeneration is crucial for the identification of possible pharmacological drugs that can positively affect the tissue regenerative capacity.
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Affiliation(s)
- Bruno Siqueira Mietto
- Laboratório de Neurodegeneração e Reparo, Departamento de Patologia, Faculdade de Medicina, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, 21941-550 Rio de Janeiro, RJ, Brazil
| | - Klauss Mostacada
- Laboratório de Neurodegeneração e Reparo, Departamento de Patologia, Faculdade de Medicina, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, 21941-550 Rio de Janeiro, RJ, Brazil
| | - Ana Maria Blanco Martinez
- Laboratório de Neurodegeneração e Reparo, Departamento de Patologia, Faculdade de Medicina, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, 21941-550 Rio de Janeiro, RJ, Brazil
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221
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Papastefanaki F, Matsas R. From demyelination to remyelination: the road toward therapies for spinal cord injury. Glia 2015; 63:1101-25. [PMID: 25731941 DOI: 10.1002/glia.22809] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 02/10/2015] [Accepted: 02/11/2015] [Indexed: 12/14/2022]
Abstract
Myelin integrity is crucial for central nervous system (CNS) physiology while its preservation and regeneration after spinal cord injury (SCI) is key to functional restoration. Disturbance of nodal organization acutely after SCI exposes the axon and triggers conduction block in the absence of overt demyelination. Oligodendrocyte (OL) loss and myelin degradation follow as a consequence of secondary damage. Here, we provide an overview of the major biological events and underlying mechanisms leading to OL death and demyelination and discuss strategies to restrain these processes. Another aspect which is critical for SCI repair is the enhancement of endogenously occurring spontaneous remyelination. Recent findings have unveiled the complex roles of innate and adaptive immune responses in remyelination and the immunoregulatory potential of the glial scar. Moreover, the intimate crosstalk between neuronal activity, oligodendrogenesis and myelination emphasizes the contribution of rehabilitation to functional recovery. With a view toward clinical applications, several therapeutic strategies have been devised to target SCI pathology, including genetic manipulation, administration of small therapeutic molecules, immunomodulation, manipulation of the glial scar and cell transplantation. The implementation of new tools such as cellular reprogramming for conversion of one somatic cell type to another or the use of nanotechnology and tissue engineering products provides additional opportunities for SCI repair. Given the complexity of the spinal cord tissue after injury, it is becoming apparent that combinatorial strategies are needed to rescue OLs and myelin at early stages after SCI and support remyelination, paving the way toward clinical translation.
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Affiliation(s)
- Florentia Papastefanaki
- Laboratory of Cellular and Molecular Neurobiology, Hellenic Pasteur Institute, Athens, 11521, Greece
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222
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Roloff F, Scheiblich H, Dewitz C, Dempewolf S, Stern M, Bicker G. Enhanced neurite outgrowth of human model (NT2) neurons by small-molecule inhibitors of Rho/ROCK signaling. PLoS One 2015; 10:e0118536. [PMID: 25714396 PMCID: PMC4340918 DOI: 10.1371/journal.pone.0118536] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 01/20/2015] [Indexed: 12/02/2022] Open
Abstract
Axonal injury in the adult human central nervous system often results in loss of sensation and motor functions. Promoting regeneration of severed axons requires the inactivation of growth inhibitory influences from the tissue environment and stimulation of the neuron intrinsic growth potential. Especially glial cell derived factors, such as chondroitin sulfate proteoglycans, Nogo-A, myelin-associated glycoprotein, and myelin in general, prevent axon regeneration. Most of the glial growth inhibiting factors converge onto the Rho/ROCK signaling pathway in neurons. Although conditions in the injured nervous system are clearly different from those during neurite outgrowth in vitro, here we use a chemical approach to manipulate Rho/ROCK signalling with small-molecule agents to encourage neurite outgrowth in cell culture. The development of therapeutic treatments requires drug testing not only on neurons of experimental animals, but also on human neurons. Using human NT2 model neurons, we demonstrate that the pain reliever Ibuprofen decreases RhoA (Ras homolog gene family, member A GTPase) activation and promotes neurite growth. Inhibition of the downstream effector Rho kinase by the drug Y-27632 results in a strong increase in neurite outgrowth. Conversely, activation of the Rho pathway by lysophosphatidic acid results in growth cone collapse and eventually to neurite retraction. Finally, we show that blocking of Rho kinase, but not RhoA results in an increase in neurons bearing neurites. Due to its anti-inflammatory and neurite growth promoting action, the use of a pharmacological treatment of damaged neural tissue with Ibuprofen should be explored.
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Affiliation(s)
- Frank Roloff
- Division of Cell Biology, University of Veterinary Medicine Hannover, Bischofsholer Damm 15/102, 30173, Hannover, Germany
| | - Hannah Scheiblich
- Division of Cell Biology, University of Veterinary Medicine Hannover, Bischofsholer Damm 15/102, 30173, Hannover, Germany
| | - Carola Dewitz
- Division of Cell Biology, University of Veterinary Medicine Hannover, Bischofsholer Damm 15/102, 30173, Hannover, Germany
| | - Silke Dempewolf
- Division of Cell Biology, University of Veterinary Medicine Hannover, Bischofsholer Damm 15/102, 30173, Hannover, Germany
| | - Michael Stern
- Division of Cell Biology, University of Veterinary Medicine Hannover, Bischofsholer Damm 15/102, 30173, Hannover, Germany
| | - Gerd Bicker
- Division of Cell Biology, University of Veterinary Medicine Hannover, Bischofsholer Damm 15/102, 30173, Hannover, Germany
- Center for Systems Neuroscience, Hannover, Germany
- * E-mail:
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223
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Nagai J, Kitamura Y, Owada K, Yamashita N, Takei K, Goshima Y, Ohshima T. Crmp4 deletion promotes recovery from spinal cord injury by neuroprotection and limited scar formation. Sci Rep 2015; 5:8269. [PMID: 25652774 PMCID: PMC4317684 DOI: 10.1038/srep08269] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 01/14/2015] [Indexed: 11/08/2022] Open
Abstract
Axonal outgrowth inhibitors and scar formation are two major obstacles to central nervous system (CNS) repair. No target molecule that regulates both axonal growth and scarring has been identified. Here we identified collapsin response mediator protein 4 (CRMP4), a common mediator of inhibitory signals after neural injury, as a crucial factor that contributes to both axonal growth inhibition and scarring after spinal cord injury (SCI). We found increases in the inhibitory and toxic forms of CRMP4 in injured spinal cord. Notably, CRMP4 expression was evident in inflammatory cells as well as in neurons after spinal cord transection. Crmp4-/- mice displayed neuroprotection against SCI and reductions in inflammatory response and scar formation. This permissive environment for axonal growth due to CRMP4 deletion restored locomotor activity at an unusually early phase of healing. These results suggest that deletion of CRMP4 is a unique therapeutic strategy that overcomes two obstacles to CNS repair after SCI.
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Affiliation(s)
- Jun Nagai
- Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, TWIns, Waseda University, Tokyo, 162-8480 Japan
- Research Fellow of Japan Society for the Promotion of Science
| | - Yoshiteru Kitamura
- Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, TWIns, Waseda University, Tokyo, 162-8480 Japan
| | - Kazuki Owada
- Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, TWIns, Waseda University, Tokyo, 162-8480 Japan
| | - Naoya Yamashita
- Department of Molecular Pharmacology and Neurobiology, Graduate School of Medicine, Yokohama City University, Yokohama 236-0004, Japan
| | - Kohtaro Takei
- Department of Medical Life Science, Graduate School of Medical Life Science, Yokohama City University, Yokohama, 236-0004, Japan
| | - Yoshio Goshima
- Department of Molecular Pharmacology and Neurobiology, Graduate School of Medicine, Yokohama City University, Yokohama 236-0004, Japan
| | - Toshio Ohshima
- Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, TWIns, Waseda University, Tokyo, 162-8480 Japan
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224
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Stiles TL, Kapiloff MS, Goldberg JL. The role of soluble adenylyl cyclase in neurite outgrowth. BIOCHIMICA ET BIOPHYSICA ACTA 2014; 1842:2561-8. [PMID: 25064589 PMCID: PMC4262618 DOI: 10.1016/j.bbadis.2014.07.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 07/11/2014] [Accepted: 07/15/2014] [Indexed: 12/25/2022]
Abstract
Axon regeneration in the mature central nervous system is limited by extrinsic inhibitory signals and a postnatal decline in neurons' intrinsic growth capacity. Neuronal levels of the second messenger cAMP are important in regulating both intrinsic growth capacity and neurons' responses to extrinsic factors. Approaches which increase intracellular cAMP in neurons enhance neurite outgrowth and facilitate regeneration after injury. Thus, understanding the factors which affect cAMP in neurons is of potential therapeutic importance. Recently, soluble adenylyl cyclase (sAC, ADCY10), the ubiquitous, non-transmembrane adenylyl cyclase, was found to play a key role in neuronal survival and axon growth. sAC is activated by bicarbonate and cations and may translate physiologic signals from metabolism and electrical activity into a neuron's decision to survive or regenerate. Here we critically review the literature surrounding sAC and cAMP signaling in neurons to further elucidate the potential role of sAC signaling in neurite outgrowth and regeneration. This article is part of a Special Issue entitled: The role of soluble adenylyl cyclase in health and disease.
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Affiliation(s)
- Travis L Stiles
- Shiley Eye Center, University of California, San Diego, CA 92093, USA
| | - Michael S Kapiloff
- Departments of Pediatrics and Medicine, Leonard M. Miller School of Medicine, University of Miami, Miami, FL 33136, USA
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225
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Stern S, Knöll B. CNS axon regeneration inhibitors stimulate an immediate early gene response via MAP kinase-SRF signaling. Mol Brain 2014; 7:86. [PMID: 25406759 PMCID: PMC4243276 DOI: 10.1186/s13041-014-0086-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 11/11/2014] [Indexed: 12/24/2022] Open
Abstract
Background CNS axon regeneration inhibitors such as Nogo and CSPGs (Chondroitin Sulfate Proteoglycans) are major extrinsic factors limiting outgrowth of severed nerve fibers. However, knowledge on intracellular signaling cascades and gene expression programs activated by these inhibitors in neurons is sparse. Herein we studied intracellular signaling cascades activated by total myelin, Nogo and CSPGs in primary mouse CNS neurons. Results Total myelin, Nogo and CSPGs stimulated gene expression activity of the serum response factor (SRF), a central gene regulator of immediate early (IEG) and actin cytoskeletal gene transcription. As demonstrated by pharmacological interference, SRF-mediated IEG activation by myelin, Nogo or CSPGs depended on MAP kinase, to a lesser extent on Rho-GTPase but not on PKA signaling. Stimulation of neurons with all three axon growth inhibitors activated the MAP kinase ERK. In addition to ERK activation, myelin activated the IEG c-Fos, an important checkpoint of neuronal survival vs. apoptosis. Employing Srf deficient neurons revealed that myelin-induced IEG activation requires SRF. This suggests an SRF function in mediating neuronal signaling evoked by axon regeneration associated inhibitors. Besides being a signaling target of axon growth inhibitors, we show that constitutively-active SRF-VP16 can be employed to circumvent neurite growth inhibition imposed by myelin, Nogo and CSPGs. Conclusion In sum, our data demonstrate that axon regeneration inhibitors such as Nogo trigger gene expression programs including an SRF-dependent IEG response via MAP kinases and Rho-GTPases.
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Affiliation(s)
- Sina Stern
- Department Molecular Biology, Eberhard-Karls-University Tübingen, Interfaculty Institute for Cell Biology, Auf der Morgenstelle 15, 72076, Tübingen, Germany. .,Current address: German Centre for Neurodegenerative Diseases (DZNE), Ludwig-Erhard-Allee 2, 53175, Bonn, Germany.
| | - Bernd Knöll
- Department Molecular Biology, Eberhard-Karls-University Tübingen, Interfaculty Institute for Cell Biology, Auf der Morgenstelle 15, 72076, Tübingen, Germany. .,Current address: Ulm University, Institute for Physiological Chemistry, 89081, Ulm, Germany.
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226
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Sengupta MB, Basu M, Iswarari S, Mukhopadhyay KK, Sardar KP, Acharyya B, Mohanty PK, Mukhopadhyay D. CSF proteomics of secondary phase spinal cord injury in human subjects: perturbed molecular pathways post injury. PLoS One 2014; 9:e110885. [PMID: 25350754 PMCID: PMC4211693 DOI: 10.1371/journal.pone.0110885] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Accepted: 09/17/2014] [Indexed: 12/29/2022] Open
Abstract
Recovery of sensory and motor functions following traumatic spinal cord injury (SCI) is dependent on injury severity. Here we identified 49 proteins from cerebrospinal fluid (CSF) of SCI patients, eight of which were differentially abundant among two severity groups of SCI. It was observed that the abundance profiles of these proteins change over a time period of days to months post SCI. Statistical analysis revealed that these proteins take part in several molecular pathways including DNA repair, protein phosphorylation, tRNA transcription, iron transport, mRNA metabolism, immune response and lipid and ATP catabolism. These pathways reflect a set of mechanisms that the system may adopt to cope up with the assault depending on the injury severity, thus leading to observed physiological responses. Apart from putting forward a picture of the molecular scenario at the injury site in a human study, this finding further delineates consequent pathways and molecules that may be altered by external intervention to restrict neural degeneration.
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Affiliation(s)
- Mohor Biplab Sengupta
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Kolkata, West Bengal, India
| | - Mahashweta Basu
- Condensed Matter Physics Division, Saha Institute of Nuclear Physics, Kolkata, West Bengal, India
| | - Sourav Iswarari
- Department of Physical Medicine & Rehabilitation, Nil Ratan Sircar Medical College & Hospital, Kolkata, West Bengal, India
| | - Kiran Kumar Mukhopadhyay
- Department of Orthopaedic Surgery, Nil Ratan Sircar Medical College & Hospital, Kolkata, West Bengal, India
| | - Krishna Pada Sardar
- Department of Orthopaedic Surgery, Nil Ratan Sircar Medical College & Hospital, Kolkata, West Bengal, India
| | - Biplab Acharyya
- Department of Orthopaedic Surgery, Nil Ratan Sircar Medical College & Hospital, Kolkata, West Bengal, India
| | - Pradeep K. Mohanty
- Condensed Matter Physics Division, Saha Institute of Nuclear Physics, Kolkata, West Bengal, India
| | - Debashis Mukhopadhyay
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Kolkata, West Bengal, India
- * E-mail:
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227
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Fujita Y, Yamashita T. Axon growth inhibition by RhoA/ROCK in the central nervous system. Front Neurosci 2014; 8:338. [PMID: 25374504 PMCID: PMC4205828 DOI: 10.3389/fnins.2014.00338] [Citation(s) in RCA: 174] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 10/06/2014] [Indexed: 12/31/2022] Open
Abstract
Rho kinase (ROCK) is a serine/threonine kinase and a downstream target of the small GTPase Rho. The RhoA/ROCK pathway is associated with various neuronal functions such as migration, dendrite development, and axonal extension. Evidence from animal studies reveals that RhoA/ROCK signaling is involved in various central nervous system (CNS) diseases, including optic nerve and spinal cord injuries, stroke, and neurodegenerative diseases. Given that RhoA/ROCK plays a critical role in the pathophysiology of CNS diseases, the development of therapeutic agents targeting this pathway is expected to contribute to the treatment of CNS diseases. The RhoA/ROCK pathway mediates the effects of myelin-associated axon growth inhibitors—Nogo, myelin-associated glycoprotein (MAG), oligodendrocyte-myelin glycoprotein (OMgp), and repulsive guidance molecule (RGM). Blocking RhoA/ROCK signaling can reverse the inhibitory effects of these molecules on axon outgrowth, and promotes axonal sprouting and functional recovery in animal models of CNS injury. To date, several RhoA/ROCK inhibitors have been under development or in clinical trials as therapeutic agents for neurological disorders. In this review, we focus on the RhoA/ROCK signaling pathway in neurological disorders. We also discuss the potential therapeutic approaches of RhoA/ROCK inhibitors for various neurological disorders.
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Affiliation(s)
- Yuki Fujita
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University Osaka, Japan ; Japan Science and Technology Agency, Core Research for Evolutional Science and Technology Tokyo, Japan
| | - Toshihide Yamashita
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University Osaka, Japan ; Japan Science and Technology Agency, Core Research for Evolutional Science and Technology Tokyo, Japan
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228
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Liang P, Liu J, Xiong J, Liu Q, Zhao J, Liang H, Zhao L, Tang H. Neural stem cell-conditioned medium protects neurons and promotes propriospinal neurons relay neural circuit reconnection after spinal cord injury. Cell Transplant 2014; 23 Suppl 1:S45-56. [PMID: 25333841 DOI: 10.3727/096368914x684989] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Human fetal neural stem cells (hNSCs) are used to treat a variety of neurological disorders involving spinal cord injury (SCI). Although their mechanism of action has been attributed to cell substitution, we examined the possibility that NSCs may have neuroprotective activities. The present article studied the action of hNSCs on protecting neurons and promoting corticospinal tract (CST) axon regeneration after SCI. hNSCs were isolated from the cortical tissue of spontaneously aborted human fetuses. The cells were removed from the NSC culture medium to acquire NSCM, thus excluding the effect of cell substitution. Continuous administration of the NSCM after the SCI resulted in extensive growth of the CST in the cervical region and more than tripled the formation of synaptic contacts between CST collaterals and propriospinal interneurons that project from the cervical level of the spinal cord to the lumbar level. NSCM reduced the number of caspase 3-positive apoptotic profiles at 7 days and protected against loss of the neurons 6 weeks after injury. NSCM promoted locomotor recovery with a five-point improvement on the BBB scale in adult rats. Thus, hNSCs help to set up a contour neural circuit via secretory factors, which may be the mechanism for their action in SCI rats. This manuscript is published as part of the International Association of Neurorestoratology (IANR) special issue of Cell Transplantation.
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Affiliation(s)
- Peng Liang
- Harbin Medical University Cancer Hospital, Harbin, China
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Joshi AR, Bobylev I, Zhang G, Sheikh KA, Lehmann HC. Inhibition of Rho-kinase differentially affects axon regeneration of peripheral motor and sensory nerves. Exp Neurol 2014; 263:28-38. [PMID: 25261755 DOI: 10.1016/j.expneurol.2014.09.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 08/27/2014] [Accepted: 09/14/2014] [Indexed: 11/29/2022]
Abstract
The small GTPase RhoA and its down-stream effector Rho-kinase (ROCK) are important effector molecules of the neuronal cytoskeleton. Modulation of the RhoA/ROCK pathway has been shown to promote axonal regeneration, however in vitro and animal studies are inconsistent regarding the extent of axonal outgrowth induced by pharmacological inhibition of ROCK. We hypothesized that injury to sensory and motor nerves result in diverse activation levels of RhoA, which may impact the response of those nerve fiber modalities to ROCK inhibition. We therefore examined the effects of Y-27632, a chemical ROCK inhibitor, on the axonal outgrowth of peripheral sensory and motor neurons grown in the presence of growth-inhibiting chondroitin sulfate proteoglycans (CSPGs). In addition we examined the effects of three different doses of Y-27632 on nerve regeneration of motor and sensory nerves in animal models of peripheral nerve crush. In vitro, sensory neurons were less responsive to Y-27632 compared to motor neurons in a non-growth permissive environment. These differences were associated with altered expression and activation of RhoA in sensory and motor axons. In vivo, systemic treatment with high doses of Y-27632 significantly enhanced the regeneration of motor axons over short distances, while the regeneration of sensory fibers remained largely unchanged. Our results support the concept that in a growth non-permissive environment, the regenerative capacity of sensory and motor axons is differentially affected by the RhoA/ROCK pathway, with motor neurons being more responsive compared to sensory. Future treatments, that are aimed to modulate RhoA activity, should consider this functional diversity.
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Affiliation(s)
- Abhijeet R Joshi
- Department of Neurology, University of Cologne, Germany; Center for Molecular Medicine Cologne, Cologne, Germany
| | - Ilja Bobylev
- Department of Neurology, University of Cologne, Germany; Center for Molecular Medicine Cologne, Cologne, Germany
| | - Gang Zhang
- Department of Neurology, University of Texas Health Sciences Centre, Houston, TX, USA
| | - Kazim A Sheikh
- Department of Neurology, University of Texas Health Sciences Centre, Houston, TX, USA
| | - Helmar C Lehmann
- Department of Neurology, University of Cologne, Germany; Center for Molecular Medicine Cologne, Cologne, Germany.
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Zhang J, Sun X, Zheng S, Liu X, Jin J, Ren Y, Luo J. Myelin basic protein induces neuron-specific toxicity by directly damaging the neuronal plasma membrane. PLoS One 2014; 9:e108646. [PMID: 25255088 PMCID: PMC4177931 DOI: 10.1371/journal.pone.0108646] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2014] [Accepted: 08/18/2014] [Indexed: 12/15/2022] Open
Abstract
The central nervous system (CNS) insults may cause massive demyelination and lead to the release of myelin-associated proteins including its major component myelin basic protein (MBP). MBP is reported to induce glial activation but its effect on neurons is still little known. Here we found that MBP specifically bound to the extracellular surface of the neuronal plasma membrane and induced neurotoxicity in vitro. This effect of MBP on neurons was basicity-dependent because the binding was blocked by acidic lipids and competed by other basic proteins. Further studies revealed that MBP induced damage to neuronal membrane integrity and function by depolarizing the resting membrane potential, increasing the permeability to cations and other molecules, and decreasing the membrane fluidity. At last, artificial liposome vesicle assay showed that MBP directly disturbed acidic lipid bilayer and resulted in increased membrane permeability. These results revealed that MBP induces neurotoxicity through its direct interaction with acidic components on the extracellular surface of neuronal membrane, which may suggest a possible contribution of MBP to the pathogenesis in the CNS disorders with myelin damage.
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Affiliation(s)
- Jie Zhang
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Xin Sun
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Division of Neurobiology, Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Sixin Zheng
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Xiao Liu
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Jinghua Jin
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Yi Ren
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, Florida, United States of America
| | - Jianhong Luo
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health of China, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- * E-mail:
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231
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Soluble adenylyl cyclase is necessary and sufficient to overcome the block of axonal growth by myelin-associated factors. J Neurosci 2014; 34:9281-9. [PMID: 25009261 DOI: 10.1523/jneurosci.1434-14.2014] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Neurons in the CNS do not regenerate following injury; regeneration is blocked by inhibitory proteins in myelin, such as myelin-associated glycoprotein (MAG). Elevating neuronal levels of the second messenger cAMP overcomes this blocked axonal outgrowth. One way to elevate cAMP is pretreating neurons with neurotrophins, such as brain-derived neurotrophic factor (BDNF). However, pleiotropic effects and poor bioavailability make exogenous administration of neurotrophins in vivo problematic; therefore, alternative targets must be considered. In neurons, two families of adenylyl cyclases synthesize cAMP, transmembrane adenylyl cyclases (tmACs), and soluble adenylyl cyclase (sAC). Here, we demonstrate that sAC is the essential source of cAMP for BDNF to overcome MAG-dependent inhibition of neurite outgrowth. Elevating sAC in rat and mouse neurons is sufficient to induce neurite outgrowth on myelin in vitro and promotes regeneration in vivo. These results suggest that stimulators of sAC might represent a novel therapeutic strategy to promote axonal growth and regeneration.
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Estrada V, Müller HW. Spinal cord injury - there is not just one way of treating it. F1000PRIME REPORTS 2014; 6:84. [PMID: 25343041 PMCID: PMC4166939 DOI: 10.12703/p6-84] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
In the last century, research in the field of spinal cord trauma has brought insightful knowledge which has led to a detailed understanding of mechanisms that are involved in injury- and recovery-related processes. The quest for a cure for the yet generally incurable condition as well as the exponential rise in gained information has brought about the development of numerous treatment approaches while at the same time the abundance of data has become quite unmanageable. Owing to an enormous amount of preclinical therapeutic approaches, this report highlights important trends rather than specific treatment strategies. We focus on current advances in the treatment of spinal cord injury and want to further draw attention to arising problems in spinal cord injury (SCI) research and discuss possible solutions.
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Affiliation(s)
- Veronica Estrada
- Molecular Neurobiology Laboratory, Department of Neurology, Heinrich-Heine-University Medical Center Düsseldorf Moorenstr. 5, 40225 Düsseldorf Germany
| | - Hans Werner Müller
- Molecular Neurobiology Laboratory, Department of Neurology, Heinrich-Heine-University Medical Center Düsseldorf Moorenstr. 5, 40225 Düsseldorf Germany
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Vilar M, Sung TC, Chen Z, García-Carpio I, Fernandez EM, Xu J, Riek R, Lee KF. Heterodimerization of p45-p75 modulates p75 signaling: structural basis and mechanism of action. PLoS Biol 2014; 12:e1001918. [PMID: 25093680 PMCID: PMC4122344 DOI: 10.1371/journal.pbio.1001918] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 06/25/2014] [Indexed: 12/26/2022] Open
Abstract
The formation of a p45-p75 heterodimer overrides p75’s inhibition of nerve regeneration by stopping p75 homodimers from forming and creating a complex with the Nogo receptor. The p75 neurotrophin receptor, a member of the tumor necrosis factor receptor superfamily, is required as a co-receptor for the Nogo receptor (NgR) to mediate the activity of myelin-associated inhibitors such as Nogo, MAG, and OMgp. p45/NRH2/PLAIDD is a p75 homologue and contains a death domain (DD). Here we report that p45 markedly interferes with the function of p75 as a co-receptor for NgR. P45 forms heterodimers with p75 and thereby blocks RhoA activation and inhibition of neurite outgrowth induced by myelin-associated inhibitors. p45 binds p75 through both its transmembrane (TM) domain and DD. To understand the underlying mechanisms, we have determined the three-dimensional NMR solution structure of the intracellular domain of p45 and characterized its interaction with p75. We have identified the residues involved in such interaction by NMR and co-immunoprecipitation. The DD of p45 binds the DD of p75 by electrostatic interactions. In addition, previous reports suggested that Cys257 in the p75 TM domain is required for signaling. We found that the interaction of the cysteine 58 of p45 with the cysteine 257 of p75 within the TM domain is necessary for p45–p75 heterodimerization. These results suggest a mechanism involving both the TM domain and the DD of p45 to regulate p75-mediated signaling. Injuries to the brain and spinal cord often result in paralysis due to the fact that the injured nerves cannot regrow to reach their normal targets and carry out their functions. At the injury sites, there are proteins released from the damaged myelin that bind the Nogo receptor (NgR) on the nerve and inhibit its regeneration. The NgR needs to form a complex with the p75 neurotrophin receptor in order to mediate this inhibitory signal. Here we found that p45, a homologue of p75, can also bind to p75 and block its inhibitory activity when overexpressed. To perform its function, p75 needs to dimerize through both its transmembrane and intracellular domains, facilitating the recruitment of several proteins. Our structural and functional studies show that p45 binds specifically to conserved regions in the p75 transmembrane and the intracellular domain and that this blocks p75 dimerization along with its downstream signaling. Thus, this study demonstrates that altering the oligomerization of p75 is a good strategy to override p75's inhibitory effects on nerve regeneration, and it opens the door for the design of specific p75 inhibitors for therapeutic applications.
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Affiliation(s)
- Marçal Vilar
- Clayton Foundation Laboratories for Peptide Biology, The Salk Institute, La Jolla, California, United States of America
- Neurodegeneration Unit, Chronic Disease Program, Spanish Institute of Health Carlos III, Madrid, Spain
- * E-mail: (K.-F.L.); (R.R.); (M.V.)
| | - Tsung-Chang Sung
- Clayton Foundation Laboratories for Peptide Biology, The Salk Institute, La Jolla, California, United States of America
| | - Zhijiang Chen
- Clayton Foundation Laboratories for Peptide Biology, The Salk Institute, La Jolla, California, United States of America
| | - Irmina García-Carpio
- Neurodegeneration Unit, Chronic Disease Program, Spanish Institute of Health Carlos III, Madrid, Spain
| | - Eva M. Fernandez
- Neurodegeneration Unit, Chronic Disease Program, Spanish Institute of Health Carlos III, Madrid, Spain
| | - Jiqing Xu
- Clayton Foundation Laboratories for Peptide Biology, The Salk Institute, La Jolla, California, United States of America
| | - Roland Riek
- Clayton Foundation Laboratories for Peptide Biology, The Salk Institute, La Jolla, California, United States of America
- Laboratory for Physical Chemistry, ETH Zürich, Zürich, Switzerland
- * E-mail: (K.-F.L.); (R.R.); (M.V.)
| | - Kuo-Fen Lee
- Clayton Foundation Laboratories for Peptide Biology, The Salk Institute, La Jolla, California, United States of America
- * E-mail: (K.-F.L.); (R.R.); (M.V.)
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Immune modulatory therapies for spinal cord injury – Past, present and future. Exp Neurol 2014; 258:91-104. [DOI: 10.1016/j.expneurol.2014.01.025] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2013] [Revised: 01/21/2014] [Accepted: 01/30/2014] [Indexed: 01/18/2023]
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Lang BT, Wang J, Filous AR, Au NPB, Ma CHE, Shen Y. Pleiotropic molecules in axon regeneration and neuroinflammation. Exp Neurol 2014; 258:17-23. [DOI: 10.1016/j.expneurol.2014.04.031] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 04/21/2014] [Accepted: 04/29/2014] [Indexed: 12/20/2022]
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Bloom O. Non-mammalian model systems for studying neuro-immune interactions after spinal cord injury. Exp Neurol 2014; 258:130-40. [PMID: 25017894 PMCID: PMC4099969 DOI: 10.1016/j.expneurol.2013.12.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Revised: 12/24/2013] [Accepted: 12/26/2013] [Indexed: 01/09/2023]
Abstract
Mammals exhibit poor recovery after injury to the spinal cord, where the loss of neurons and neuronal connections can be functionally devastating. In contrast, it has long been appreciated that many non-mammalian vertebrate species exhibit significant spontaneous functional recovery after spinal cord injury (SCI). Identifying the biological responses that support an organism's inability or ability to recover function after SCI is an important scientific and medical question. While recent advances have been made in understanding the responses to SCI in mammals, we remain without an effective clinical therapy for SCI. A comparative biological approach to understanding responses to SCI in non-mammalian vertebrates will yield important insights into mechanisms that promote recovery after SCI. Presently, mechanistic studies aimed at elucidating responses, both intrinsic and extrinsic to neurons, that result in different regenerative capacities after SCI across vertebrates are just in their early stages. There are several inhibitory mechanisms proposed to impede recovery from SCI in mammals, including reactive gliosis and scarring, myelin associated proteins, and a suboptimal immune response. One hypothesis to explain the robust regenerative capacity of several non-mammalian vertebrates is a lack of some or all of these inhibitory signals. This review presents the current knowledge of immune responses to SCI in several non-mammalian species that achieve anatomical and functional recovery after SCI. This subject is of growing interest, as studies increasingly show both beneficial and detrimental roles of the immune response following SCI in mammals. A long-term goal of biomedical research in all experimental models of SCI is to understand how to promote functional recovery after SCI in humans. Therefore, understanding immune responses to SCI in non-mammalian vertebrates that achieve functional recovery spontaneously may identify novel strategies to modulate immune responses in less regenerative species and promote recovery after SCI.
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Affiliation(s)
- Ona Bloom
- The Feinstein Institute for Medical Research, 350 Community Drive, Manhasset, NY 11030, USA; The Hofstra North Shore-LIJ School of Medicine, Hempstead Turnpike, Hempstead, NY 11549, USA.
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Structural features of the Nogo receptor signaling complexes at the neuron/myelin interface. Neurosci Res 2014; 87:1-7. [PMID: 24956133 DOI: 10.1016/j.neures.2014.06.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 05/23/2014] [Accepted: 06/13/2014] [Indexed: 11/22/2022]
Abstract
Upon spinal cord injury, the central nervous system axons are unable to regenerate, partially due to the repulsive action of myelin inhibitors, such as the myelin-associated glycoprotein (MAG), Nogo-A and the oligodendrocyte myelin glycoprotein (OMgp). These inhibitors bind and signal through a single receptor/co-receptor complex that comprises of NgR1/LINGO-1 and either p75 or TROY, triggering intracellular downstream signaling that impedes the re-growth of axons. Structure-function analysis of myelin inhibitors and their neuronal receptors, particularly the NgRs, have provided novel information regarding the molecular details of the inhibitor/receptor/co-receptor interactions. Structural and biochemical studies have revealed the architecture of many of these proteins and identified the molecular regions important for assembly of the inhibitory signaling complexes. It was also recently shown that gangliosides, such as GT1b, mediate receptor/co-receptor binding. In this review, we highlight these studies and summarize our current understanding of the multi-protein cell-surface complexes mediating inhibitory signaling events at the neuron/myelin interface.
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238
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Wang X, Xu XM. Long-term survival, axonal growth-promotion, and myelination of Schwann cells grafted into contused spinal cord in adult rats. Exp Neurol 2014; 261:308-19. [PMID: 24873728 DOI: 10.1016/j.expneurol.2014.05.022] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 05/18/2014] [Accepted: 05/20/2014] [Indexed: 01/25/2023]
Abstract
Schwann cells (SCs) have been considered to be one of the most promising cell types for transplantation to treat spinal cord injury (SCI) due to their unique growth-promoting properties. Despite the extensive use as donor cells for transplantation in SCI models, the fate of SCs is controversial due in part to the lack of a reliable marker for tracing the grafted SCs. To precisely assess the fate and temporal profile of transplanted SCs, we isolated purified SCs from sciatic nerves of adult transgenic rats overexpressing GFP (SCs-GFP). SCs-GFP were directly injected into the epicenter of a moderate contusive SCI at the mid-thoracic level at 1week post-injury. The number of SCs-GFP or SCs-GFP labeled with Bromodeoxyuridine (BrdU) was quantified at 5min, 1day, and 1, 2, 4, 12 and 24weeks after cell injection. Basso, Beattie, and Bresnahan (BBB) locomotor rating scale, footfall error, thermal withdrawal latency, and footprint analysis were performed before and after the SCs-GFP transplantation. After transplantation, SCs-GFP quickly filled the lesion cavity. A remarkable survival of grafted SCs-GFP up to 24weeks post-grafting was observed with clearly identified SC individuals. SCs-GFP proliferated after injection, peaked at 2weeks (26% of total SCs-GFP), decreased thereafter, and ceased at 12weeks post-grafting. Although grafted SCs-GFP were mainly confined within the border of surrounding host tissue, they migrated along the central canal for up to 5.0mm at 4weeks post-grafting. Within the lesion site, grafted SCs-GFP myelinated regenerated axons and expressed protein zero (P0) and myelin basic protein (MBP). Within the SCs-GFP grafts, new blood vessels were formed. Except for a significant decrease of angle of rotation in the footprint analysis, we did not observe significant behavioral improvements in BBB locomotor rating scale, thermal withdrawal latency, or footfall errors, compared to the control animals that received no SCs-GFP. We conclude that SCs-GFP can survive remarkably well, proliferate, migrate along the central canal, and myelinate regenerated axons when being grafted into a clinically-relevant contusive SCI in adult rats. Combinatorial strategies, however, are essential to achieve a more meaningful functional regeneration of which SCs may play a significant role.
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Affiliation(s)
- Xiaofei Wang
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Xiao-Ming Xu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
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Skaper SD, Facci L, Giusti P. Mast cells, glia and neuroinflammation: partners in crime? Immunology 2014; 141:314-27. [PMID: 24032675 DOI: 10.1111/imm.12170] [Citation(s) in RCA: 171] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Revised: 08/31/2013] [Accepted: 09/04/2013] [Indexed: 12/12/2022] Open
Abstract
Glia and microglia in particular elaborate pro-inflammatory molecules that play key roles in central nervous system (CNS) disorders from neuropathic pain and epilepsy to neurodegenerative diseases. Microglia respond also to pro-inflammatory signals released from other non-neuronal cells, mainly those of immune origin such as mast cells. The latter are found in most tissues, are CNS resident, and traverse the blood-spinal cord and blood-brain barriers when barrier compromise results from CNS pathology. Growing evidence of mast cell-glia communication opens new perspectives for the development of therapies targeting neuroinflammation by differentially modulating activation of non-neuronal cells that normally control neuronal sensitization - both peripherally and centrally. Mast cells and glia possess endogenous homeostatic mechanisms/molecules that can be up-regulated as a result of tissue damage or stimulation of inflammatory responses. Such molecules include the N-acylethanolamine family. One such member, N-palmitoylethanolamine is proposed to have a key role in maintenance of cellular homeostasis in the face of external stressors provoking, for example, inflammation. N-Palmitoylethanolamine has proven efficacious in mast-cell-mediated experimental models of acute and neurogenic inflammation. This review will provide an overview of recent progress relating to the pathobiology of neuroinflammation, the role of microglia, neuroimmune interactions involving mast cells and the possibility that mast cell-microglia cross-talk contributes to the exacerbation of acute symptoms of chronic neurodegenerative disease and accelerates disease progression, as well as promoting pain transmission pathways. We will conclude by considering the therapeutic potential of treating systemic inflammation or blockade of signalling pathways from the periphery to the brain in such settings.
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Affiliation(s)
- Stephen D Skaper
- Dipartimento di Scienze del Farmaco, Largo 'Egidio Meneghetti' 2, Università degli Studi di Padova, Padova, Italy
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Nerve growth factor improves functional recovery by inhibiting endoplasmic reticulum stress-induced neuronal apoptosis in rats with spinal cord injury. J Transl Med 2014; 12:130. [PMID: 24884850 PMCID: PMC4039547 DOI: 10.1186/1479-5876-12-130] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Accepted: 03/14/2014] [Indexed: 12/03/2022] Open
Abstract
Background Endoplasmic reticulum (ER) stress-induced apoptosis plays a major role in various diseases, including spinal cord injury (SCI). Nerve growth factor (NGF) show neuroprotective effect and improve the recovery of SCI, but the relations of ER stress-induced apoptosis and the NGF therapeutic effect in SCI still unclear. Methods Young adult female Sprague-Dawley rats’s vertebral column was exposed and a laminectomy was done at T9 vertebrae and moderate contusion injuries were performed using a vascular clip. NGF stock solution was diluted with 0.9% NaCl and administered intravenously at a dose of 20 μg/kg/day after SCI and then once per day until they were executed. Subsequently, the rats were executed at 1d, 3 d, 7d and 14d. The locomotor activities of SCI model rats were tested by the 21-point Basso-Beattie-Bresnahan (BBB) locomotion scale, inclined plane test and footprint analysis. In addition, Western blot analysis was performed to identify the expression of ER-stress related proteins including CHOP, GRP78 and caspase-12 both in vivo and in vitro. The level of cell apoptosis was determined by TUNEL in vivo and Flow cytometry in vitro. Relative downstream signals Akt/GSK-3β and ERK1/2were also analyzed with or without inhibitors in vitro. Results Our results demonstrated that ER stress-induced apoptosis was involved in the injury of SCI model rats. NGF administration improved the motor function recovery and increased the neurons survival in the spinal cord lesions of the model rats. NGF decreases neuron apoptosis which measured by TUNEL and inhibits the activation of caspase-3 cascade. The ER stress-induced apoptosis response proteins CHOP, GRP78 and caspase-12 are inhibited by NGF treatment. Meanwhile, NGF administration also increased expression of growth-associated protein 43 (GAP43). The administration of NGF activated downstream signals Akt/GSK-3β and ERK1/2 in ER stress cell model in vitro. Conclusion The neuroprotective role of NGF in the recovery of SCI is related to the inhibition of ER stress-induced cell death via the activation of downstream signals, also suggested a new trend of NGF translational drug development in the central neural system injuries which involved in the regulation of chronic ER stress.
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Sharma TP, McDowell CM, Liu Y, Wagner AH, Thole D, Faga BP, Wordinger RJ, Braun TA, Clark AF. Optic nerve crush induces spatial and temporal gene expression patterns in retina and optic nerve of BALB/cJ mice. Mol Neurodegener 2014; 9:14. [PMID: 24767545 PMCID: PMC4113182 DOI: 10.1186/1750-1326-9-14] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 04/18/2014] [Indexed: 12/18/2022] Open
Abstract
Background Central nervous system (CNS) trauma and neurodegenerative disorders trigger a cascade of cellular and molecular events resulting in neuronal apoptosis and regenerative failure. The pathogenic mechanisms and gene expression changes associated with these detrimental events can be effectively studied using a rodent optic nerve crush (ONC) model. The purpose of this study was to use a mouse ONC model to: (a) evaluate changes in retina and optic nerve (ON) gene expression, (b) identify neurodegenerative pathogenic pathways and (c) discover potential new therapeutic targets. Results Only 54% of total neurons survived in the ganglion cell layer (GCL) 28 days post crush. Using Bayesian Estimation of Temporal Regulation (BETR) gene expression analysis, we identified significantly altered expression of 1,723 and 2,110 genes in the retina and ON, respectively. Meta-analysis of altered gene expression (≥1.5, ≤-1.5, p < 0.05) using Partek and DAVID demonstrated 28 up and 20 down-regulated retinal gene clusters and 57 up and 41 down-regulated optic nerve clusters. Regulated gene clusters included regenerative change, synaptic plasticity, axonogenesis, neuron projection, and neuron differentiation. Expression of selected genes (Vsnl1, Syt1, Synpr and Nrn1) from retinal and ON neuronal clusters were quantitatively and qualitatively examined for their relation to axonal neurodegeneration by immunohistochemistry and qRT-PCR. Conclusion A number of detrimental gene expression changes occur that contribute to trauma-induced neurodegeneration after injury to ON axons. Nrn1 (synaptic plasticity gene), Synpr and Syt1 (synaptic vesicle fusion genes), and Vsnl1 (neuron differentiation associated gene) were a few of the potentially unique genes identified that were down-regulated spatially and temporally in our rodent ONC model. Bioinformatic meta-analysis identified significant tissue-specific and time-dependent gene clusters associated with regenerative changes, synaptic plasticity, axonogenesis, neuron projection, and neuron differentiation. These ONC induced neuronal loss and regenerative failure associated clusters can be extrapolated to changes occurring in other forms of CNS trauma or in clinical neurodegenerative pathological settings. In conclusion, this study identified potential therapeutic targets to address two key mechanisms of CNS trauma and neurodegeneration: neuronal loss and regenerative failure.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Abbot F Clark
- North Texas Eye Research Institute, Ft, Worth, TX USA.
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Wyatt LA, Filbin MT, Keirstead HS. PTEN inhibition enhances neurite outgrowth in human embryonic stem cell-derived neuronal progenitor cells. J Comp Neurol 2014; 522:2741-55. [PMID: 24610700 DOI: 10.1002/cne.23580] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 09/29/2013] [Accepted: 10/07/2013] [Indexed: 12/27/2022]
Abstract
We investigated the role of PTEN (phosphatase and tensin homolog deleted on chromosome 10) during neurite outgrowth of human embryonic stem cell (hESC)-derived neuronal progenitors. PTEN inhibits phosphoinositide 3-kinase (PI3K)/Akt signaling, a common and central outgrowth and survival pathway downstream of neuronal growth factors. It is known that PTEN inhibition, by either polymorphic mutation or gene deletion, can lead to the development of tumorigenesis (Stambolic et al., ; Tamura et al., ). However, temporary inhibition of PTEN, through pharmacological manipulation, could regulate signaling events such as the PI3K/Akt signaling pathway, leading to enhanced recovery of central nervous system (CNS) injury and disease. We demonstrate that pharmacological inhibition of PTEN in hESC-derived neuronal progenitors significantly increased neurite outgrowth in vitro in a dose- and time-dependent manner. Our results indicate that inhibition of PTEN augments neurite outgrowth beyond that of traditional methods such as elevation of intracellular cyclic adenosine monophosphate (cAMP) levels, and depends on upregulation of the PI3K/Akt signaling pathway and its downstream effectors, such as mammalian target of rapamycin (mTOR). PTEN inhibition also rescued neurite outgrowth over an inhibitory substrate in vitro. These findings indicate a remarkable impact on hESC-derived neuronal progenitor plasticity through PTEN inhibition. Overall, these findings identify a novel therapeutic strategy for neurite outgrowth in CNS injury and disease.
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Affiliation(s)
- Lindsey A Wyatt
- Department of Anatomy and Neurobiology, Sue and Bill Gross Stem Cell Research Center, Reeve-Irvine Research Center, School of Medicine, University of California at Irvine, Irvine, California, 92697-4292
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Meng X, Yao W, Cheng J, Zhang X, Jin L, Yu H, Chen X, Wang F, Cao H. Regioselective chemoenzymatic synthesis of ganglioside disialyl tetrasaccharide epitopes. J Am Chem Soc 2014; 136:5205-8. [PMID: 24649890 PMCID: PMC4210053 DOI: 10.1021/ja5000609] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2014] [Indexed: 02/01/2023]
Abstract
A novel chemoenzymatic approach for the synthesis of disialyl tetrasaccharide epitopes found as the terminal oligosaccharides of GD1α, GT1aα, and GQ1bα is described. It relies on chemical manipulation of enzymatically generated trisaccharides as conformationally constrained acceptors for regioselective enzymatic α2-6-sialylation. This strategy provides a new route for easy access to disialyl tetrasaccharide epitopes and their derivatives.
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Affiliation(s)
- Xin Meng
- National
Glycoengineering Research Center, School of Pharmaceutical Science, Shandong University, Jinan 250012, China
| | - Wenlong Yao
- National
Glycoengineering Research Center, School of Pharmaceutical Science, Shandong University, Jinan 250012, China
| | - Jiansong Cheng
- College
of Pharmacy, Nankai University, Tianjin 300071, China
| | - Xu Zhang
- National
Glycoengineering Research Center, School of Pharmaceutical Science, Shandong University, Jinan 250012, China
| | - Lan Jin
- National
Glycoengineering Research Center, School of Pharmaceutical Science, Shandong University, Jinan 250012, China
| | - Hai Yu
- Department
of Chemistry, University of California, Davis, California 95616, United States
| | - Xi Chen
- Department
of Chemistry, University of California, Davis, California 95616, United States
| | - Fengshan Wang
- National
Glycoengineering Research Center, School of Pharmaceutical Science, Shandong University, Jinan 250012, China
- Key
Laboratory of Chemical Biology (Ministry of Education), Shandong University, Jinan 250012, China
| | - Hongzhi Cao
- National
Glycoengineering Research Center, School of Pharmaceutical Science, Shandong University, Jinan 250012, China
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244
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Estrada V, Brazda N, Schmitz C, Heller S, Blazyca H, Martini R, Müller HW. Long-lasting significant functional improvement in chronic severe spinal cord injury following scar resection and polyethylene glycol implantation. Neurobiol Dis 2014; 67:165-79. [PMID: 24713436 DOI: 10.1016/j.nbd.2014.03.018] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 03/17/2014] [Accepted: 03/28/2014] [Indexed: 01/04/2023] Open
Abstract
We identified a suitable biomatrix that improved axon regeneration and functional outcome after partial (moderate) and complete (severe) chronic spinal cord injury (SCI) in rat. Five weeks after dorsal thoracic hemisection injury the lesion scar was resected via aspiration and the resulting cavity was filled with different biopolymers such as Matrigel™, alginate-hydrogel and polyethylene glycol 600 (PEG) all of which have not previously been used as sole graft-materials in chronic SCI. Immunohistological staining revealed marked differences between these compounds regarding axon regeneration, invasion/elongation of astrocytes, fibroblasts, endothelial and Schwann cells, revascularization, and collagen deposition. According to axon regeneration-supporting effects, the biopolymers could be ranked in the order PEG>>alginate-hydrogel>Matrigel™. Even after complete chronic transection, the PEG-bridge allowed long-distance axon regeneration through the grafted area and for, at least, 1cm beyond the lesion/graft border. As revealed by electron microscopy, bundles of regenerating axons within the matrix area received myelin ensheathment from Schwann cells. The beneficial effects of PEG-implantation into the resection-cavity were accompanied by long-lasting significant locomotor improvement over a period of 8months. Following complete spinal re-transection at the rostral border of the PEG-graft the locomotor recovery was aborted, suggesting a functional role of regenerated axons in the initial locomotor improvement. In conclusion, scar resection and subsequent implantation of PEG into the generated cavity leads to tissue recovery, axon regeneration, myelination and functional improvement that have not been achieved before in severe chronic SCI.
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Affiliation(s)
- Veronica Estrada
- Molecular Neurobiology Laboratory, Department of Neurology, Heinrich-Heine-University Medical Center Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Nicole Brazda
- Molecular Neurobiology Laboratory, Department of Neurology, Heinrich-Heine-University Medical Center Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Christine Schmitz
- Molecular Neurobiology Laboratory, Department of Neurology, Heinrich-Heine-University Medical Center Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Silja Heller
- Molecular Neurobiology Laboratory, Department of Neurology, Heinrich-Heine-University Medical Center Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Heinrich Blazyca
- Department of Neurology, Developmental Neurobiology, University Medical Center Würzburg, Josef-Schneider-Str. 11, 97080 Würzburg, Germany
| | - Rudolf Martini
- Department of Neurology, Developmental Neurobiology, University Medical Center Würzburg, Josef-Schneider-Str. 11, 97080 Würzburg, Germany
| | - Hans Werner Müller
- Molecular Neurobiology Laboratory, Department of Neurology, Heinrich-Heine-University Medical Center Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany.
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245
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Bryson JB, Machado CB, Crossley M, Stevenson D, Bros-Facer V, Burrone J, Greensmith L, Lieberam I. Optical control of muscle function by transplantation of stem cell-derived motor neurons in mice. Science 2014; 344:94-7. [PMID: 24700859 PMCID: PMC5947756 DOI: 10.1126/science.1248523] [Citation(s) in RCA: 115] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Damage to the central nervous system caused by traumatic injury or neurological disorders can lead to permanent loss of voluntary motor function and muscle paralysis. Here, we describe an approach that circumvents central motor circuit pathology to restore specific skeletal muscle function. We generated murine embryonic stem cell-derived motor neurons that express the light-sensitive ion channel channelrhodopsin-2, which we then engrafted into partially denervated branches of the sciatic nerve of adult mice. These engrafted motor neurons not only reinnervated lower hind-limb muscles but also enabled their function to be restored in a controllable manner using optogenetic stimulation. This synthesis of regenerative medicine and optogenetics may be a successful strategy to restore muscle function after traumatic injury or disease.
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Affiliation(s)
- J. Barney Bryson
- Sobell Department of Motor Neuroscience and Movement Disorders, University College London (UCL) Institute of Neurology, London, UK
| | - Carolina Barcellos Machado
- Medical Research Council (MRC) Centre for Developmental Neurobiology, King’s College London, Guy’s Hospital Campus, London, UK
| | - Martin Crossley
- Medical Research Council (MRC) Centre for Developmental Neurobiology, King’s College London, Guy’s Hospital Campus, London, UK
| | - Danielle Stevenson
- Medical Research Council (MRC) Centre for Developmental Neurobiology, King’s College London, Guy’s Hospital Campus, London, UK
| | - Virginie Bros-Facer
- Sobell Department of Motor Neuroscience and Movement Disorders, University College London (UCL) Institute of Neurology, London, UK
| | - Juan Burrone
- Medical Research Council (MRC) Centre for Developmental Neurobiology, King’s College London, Guy’s Hospital Campus, London, UK
| | - Linda Greensmith
- Sobell Department of Motor Neuroscience and Movement Disorders, University College London (UCL) Institute of Neurology, London, UK
- MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, London, UK
| | - Ivo Lieberam
- Medical Research Council (MRC) Centre for Developmental Neurobiology, King’s College London, Guy’s Hospital Campus, London, UK
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246
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Smith GM, Liu Y, Hong JW. Quantitative assessment of neurite outgrowth over growth promoting or inhibitory substrates. Methods Mol Biol 2014; 1078:153-61. [PMID: 23975829 DOI: 10.1007/978-1-62703-640-5_14] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The use of sensory neurons and assessment of neurite outgrowth in vitro is an important part of understanding neuronal development and plasticity. Cultures of rat dorsal root ganglion (DRG) neurons provide quantitative results very quickly and, when grown on growth promoting or inhibitory substrates, can be utilized to study axonal growth, neurotrophic dependence, structure and function of growth cones. Since we are interested in axon regeneration and targeting, we have sought to promote neurite outgrowth by refining the techniques of growing DRG neurons in culture. This chapter describes detailed methods for the dissection and purification of DRG neurons and quantitative assessment of neurite on promoting or inhibitory substrates.
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Affiliation(s)
- George M Smith
- Shriners Hospital Pediatric Research Center, Temple University School of Medicine, Philadelphia, PA, USA
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247
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Zhang L, Kaneko S, Kikuchi K, Sano A, Maeda M, Kishino A, Shibata S, Mukaino M, Toyama Y, Liu M, Kimura T, Okano H, Nakamura M. Rewiring of regenerated axons by combining treadmill training with semaphorin3A inhibition. Mol Brain 2014; 7:14. [PMID: 24618249 PMCID: PMC4008261 DOI: 10.1186/1756-6606-7-14] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Accepted: 02/12/2014] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Rats exhibit extremely limited motor function recovery after total transection of the spinal cord (SCT). We previously reported that SM-216289, a semaphorin3A inhibitor, enhanced axon regeneration and motor function recovery in SCT adult rats. However, these effects were limited because most regenerated axons likely do not connect to the right targets. Thus, rebuilding the appropriate connections for regenerated axons may enhance recovery. In this study, we combined semaphorin3A inhibitor treatment with extensive treadmill training to determine whether combined treatment would further enhance the "rewiring" of regenerated axons. In this study, which aimed for clinical applicability, we administered a newly developed, potent semaphorin3A inhibitor, SM-345431 (Vinaxanthone), using a novel drug delivery system that enables continuous drug delivery over the period of the experiment. RESULTS Treatment with SM-345431 using this delivery system enhanced axon regeneration and produced significant, but limited, hindlimb motor function recovery. Although extensive treadmill training combined with SM-345431 administration did not further improve axon regeneration, hindlimb motor performance was restored, as evidenced by the significant improvement in the execution of plantar steps on a treadmill. In contrast, control SCT rats could not execute plantar steps at any point during the experimental period. Further analyses suggested that this strategy reinforced the wiring of central pattern generators in lumbar spinal circuits, which, in turn, led to enhanced motor function recovery (especially in extensor muscles). CONCLUSIONS This study highlights the importance of combining treatments that promote axon regeneration with specific and appropriate rehabilitations that promote rewiring for the treatment of spinal cord injury.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Hideyuki Okano
- Department of Orthopedic Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo 160-8582, Japan.
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248
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Abstract
Injuries to peripheral nerves can cause paralysis and sensory disturbances, but such functional impairments are often short lived because of efficient regeneration of damaged axons. The time required for functional recovery, however, increases with advancing age (Verdú et al., 2000; Kawabuchi et al., 2011). Incomplete or delayed recovery after peripheral nerve damage is a major health concern in the aging population because it can severely restrict a person's mobility and independence. A variety of possible causes have been suggested to explain why nervous systems in aged individuals recover more slowly from nerve damage. Potential causes include age-related declines in the regenerative potential of peripheral axons and decreases in the supply or responsivity to trophic and/or tropic factors. However, there have been few direct analyses of age-related axon regeneration. Our aim here was to observe axons directly in young and old mice as they regenerate and ultimately reoccupy denervated neuromuscular synaptic sites to learn what changes in this process are age related. We find that damaged nerves in aged animals clear debris more slowly than nerves in young animals and that the greater number of obstructions regenerating axons encounter in the endoneurial tubes of old animals give rise to slower regeneration. Surprisingly, however, axons from aged animals regenerate quickly when not confronted by debris and reoccupy neuromuscular junction sites efficiently. These results imply that facilitating clearance of axon debris might be a good target for the treatment of nerve injury in the aged.
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249
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Abstract
Axon regeneration is hindered by a decline of intrinsic axon growth capability in mature neurons. Reversing this decline is associated with the induction of a large repertoire of regeneration-associated genes (RAGs), but the underlying regulatory mechanisms of the transcriptional changes are largely unknown. Here, we establish a correlation between diminished axon growth potential and histone 4 (H4) hypoacetylation. When neurons are triggered into a growth state, as in the conditioning lesion paradigm, H4 acetylation is restored, and RAG transcription is initiated. We have identified a set of target genes of Smad1, a proregenerative transcription factor, in conditioned DRG neurons. We also show that, during the epigenetic reprogramming process, histone-modifying enzymes work together with Smad1 to facilitate transcriptional regulation of RAGs. Importantly, targeted pharmacological modulation of the activity of histone-modifying enzymes, such as histone deacetylases, leads to induction of multiple RAGs and promotion of sensory axon regeneration in a mouse model of spinal cord injury. Our findings suggest epigenetic modulation as a potential therapeutic strategy to enhance axon regeneration.
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250
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Deng B, Gao F, Liu FF, Zhao XH, Yu CY, Ju G, Xu LX, Wang J. Two monoclonal antibodies recognising aa 634-668 and aa 1026-1055 of NogoA enhance axon extension and branching in cultured neurons. PLoS One 2014; 9:e88554. [PMID: 24533107 PMCID: PMC3922884 DOI: 10.1371/journal.pone.0088554] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 01/07/2014] [Indexed: 01/16/2023] Open
Abstract
In a previous study, we generated two monoclonal antibodies (mAbs) in mice, aNogoA-N and aNogo-66 mAb, which were raised against recombinant N-terminal fragments of rat NogoA and Nogo-66, respectively. When compared with the commercial rabbit anti-rat NogoA polyclonal antibody (pAb), which can specifically recognise NogoA, the two mAbs were also specific for the NogoA antigen in immunofluorescence histochemical (IHC) staining and Western blot (WB) analysis. Serial truncations of NogoA covering the N-terminal region of NogoA (aa 570–691) and Nogo-66 (aa 1026–1091) were expressed in E. coli. The epitopes recognised by aNogoA-N and aNogo-66 are located in the aa 634–668 and aa 1026–1055 regions of NogoA, respectively. Both mAbs remarkably enhanced the axon growth and branching of cultured hippocampal neurons in vitro. These results suggest that the antibodies that bind to aa 634–668 and aa 1026–1055 of NogoA may have stimulatory effects on axon growth and branching. Additionally, the two mAbs that we generated are specific for NogoA and significantly block NogoA function. In conclusion, two sites in NogoA located within aa 634–668 and aa 1026–1055 are recognised by our two antibodies and are novel and potentially promising targets for repair after central nervous system (CNS) injury.
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Affiliation(s)
- Bin Deng
- Institute of Neurosciences, the Fourth Military Medical University, Xi'an, China
- Department of Anesthesiology, Stomatological College, Fourth Military Medical University, Xi'an, China
| | - Fei Gao
- Department of Clinical Laboratory, No. 174 Hospital of People's Liberation Army, Xiamen, China
| | - Fang-Fang Liu
- Institute of Neurosciences, the Fourth Military Medical University, Xi'an, China
| | - Xiang-Hui Zhao
- Institute of Neurosciences, the Fourth Military Medical University, Xi'an, China
| | - Cai-Yong Yu
- Institute of Neurosciences, the Fourth Military Medical University, Xi'an, China
| | - Gong Ju
- Institute of Neurosciences, the Fourth Military Medical University, Xi'an, China
| | - Li-Xian Xu
- Department of Anesthesiology, Stomatological College, Fourth Military Medical University, Xi'an, China
- * E-mail: (JW); (LXX)
| | - Jian Wang
- Institute of Neurosciences, the Fourth Military Medical University, Xi'an, China
- * E-mail: (JW); (LXX)
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