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Brown BL, Anil N, States G, Whittemore SR, Magnuson DSK. Long ascending propriospinal neurons are heterogenous and subject to spinal cord injury induced anatomic plasticity. Exp Neurol 2024; 373:114631. [PMID: 38070723 PMCID: PMC10922963 DOI: 10.1016/j.expneurol.2023.114631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 11/15/2023] [Accepted: 11/29/2023] [Indexed: 12/21/2023]
Abstract
Long ascending propriospinal neurons (LAPNs) are a subset of spinal interneurons that provide direct connectivity between distant spinal segments. Here, we focus specifically on an anatomically defined population of "inter-enlargement" LAPNs with cell bodies at L2/3 and terminals at C5/6. Previous studies showed that silencing LAPNs in awake and freely moving animals disrupted interlimb coordination of the hindlimbs, forelimbs, and heterolateral limb pairs. Surprisingly, despite a proportion of LAPNs being anatomically intact post- spinal cord injury (SCI), silencing them improved locomotor function but only influenced coordination of the hindlimb pair. Given the functional significance of LAPNs pre- and post-SCI, we characterized their anatomy and SCI-induced anatomical plasticity. This detailed anatomical characterization revealed three morphologically distinct subsets of LAPNs that differ in soma size, neurite complexity and/or neurite orientation. Following a mild thoracic contusive SCI there was a marked shift in neurite orientation in two of the LAPN subsets to a more dorsoventral orientation, and collateral densities decreased in the cervical enlargement but increased just caudal to the injury epicenter. These post-SCI anatomical changes potentially reflect maladaptive plasticity and an effort to establish new functional inputs from sensory afferents that sprout post-SCI to achieve circuitry homeostasis.
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Affiliation(s)
- Brandon L Brown
- Interdisciplinary Program in Translational Neuroscience, University of Louisville, Louisville, KY, United States; Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States; Department of Anatomical Sciences and Neurobiology, School of Medicine, University of Louisville, Louisville, KY, United States
| | - Neha Anil
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States; Department of Bioengineering, J.B. Speed School of Engineering, University of Louisville, Louisville, KY, United States
| | - Gregory States
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States; Department of Anatomical Sciences and Neurobiology, School of Medicine, University of Louisville, Louisville, KY, United States
| | - Scott R Whittemore
- Interdisciplinary Program in Translational Neuroscience, University of Louisville, Louisville, KY, United States; Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States; Department of Anatomical Sciences and Neurobiology, School of Medicine, University of Louisville, Louisville, KY, United States; Department of Neurological Surgery, School of Medicine, University of Louisville, Louisville, KY, United States
| | - David S K Magnuson
- Interdisciplinary Program in Translational Neuroscience, University of Louisville, Louisville, KY, United States; Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States; Department of Anatomical Sciences and Neurobiology, School of Medicine, University of Louisville, Louisville, KY, United States; Department of Bioengineering, J.B. Speed School of Engineering, University of Louisville, Louisville, KY, United States; Department of Neurological Surgery, School of Medicine, University of Louisville, Louisville, KY, United States.
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Gouveia D, Correia J, Cardoso A, Carvalho C, Oliveira AC, Almeida A, Gamboa Ó, Ribeiro L, Branquinho M, Sousa A, Lopes B, Sousa P, Moreira A, Coelho A, Rêma A, Alvites R, Ferreira A, Maurício AC, Martins Â. Intensive neurorehabilitation and allogeneic stem cells transplantation in canine degenerative myelopathy. Front Vet Sci 2023; 10:1192744. [PMID: 37520009 PMCID: PMC10374290 DOI: 10.3389/fvets.2023.1192744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 06/12/2023] [Indexed: 08/01/2023] Open
Abstract
Introduction Degenerative myelopathy (DM) is a neurodegenerative spinal cord disease with upper motor neurons, with progressive and chronic clinical signs, similar to amyotrophic lateral sclerosis (ALS). DM has a complex etiology mainly associated with SOD1 gene mutation and its toxic role, with no specific treatment. Daily intensive rehabilitation showed survival time near 8 months but most animals are euthanized 6-12 months after clinical signs onset. Methods This prospective controlled blinded cohort clinical study aims to evaluate the neural regeneration response ability of DM dogs subjected to an intensive neurorehabilitation protocol with mesenchymal stem cells (MSCs) transplantation. In total, 13 non-ambulatory (OFS 6 or 8) dogs with homozygous genotype DM/DM and diagnosed by exclusion were included. All were allocated to the intensive neurorehabilitation with MSCs protocol (INSCP) group (n = 8) or to the ambulatory rehabilitation protocol (ARP) group (n = 5), which differ in regard to training intensity, modalities frequency, and MSCs transplantation. The INSCP group was hospitalized for 1 month (T0 to T1), followed by MSCs transplantation (T1) and a second month (T2), whereas the ARP group was under ambulatory treatment for the same 2 months. Results Survival mean time of total population was 375 days, with 438 days for the INSCP group and 274 for the ARP group, with a marked difference on the Kaplan-Meier survival analysis. When comparing the literature's results, there was also a clear difference in the one-sample t-test (p = 0.013) with an increase in time of approximately 70%. OFS classifications between groups at each time point were significantly different (p = 0.008) by the one-way ANOVA and the independent sample t-test. Discussion This INSCP showed to be safe, feasible, and a possibility for a long progression of DM dogs with quality of life and functional improvement. This study should be continued.
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Affiliation(s)
- Débora Gouveia
- Arrábida Veterinary Hospital, Arrábida Animal Rehabilitation Center, Setubal, Portugal
- Superior School of Health, Protection and Animal Welfare, Polytechnic Institute of Lusophony, Lisboa, Portugal
- Faculty of Veterinary Medicine, Lusófona University, Lisboa, Portugal
| | - Jéssica Correia
- Arrábida Veterinary Hospital, Arrábida Animal Rehabilitation Center, Setubal, Portugal
- Faculty of Veterinary Medicine, Lusófona University, Lisboa, Portugal
| | - Ana Cardoso
- Arrábida Veterinary Hospital, Arrábida Animal Rehabilitation Center, Setubal, Portugal
- Superior School of Health, Protection and Animal Welfare, Polytechnic Institute of Lusophony, Lisboa, Portugal
| | - Carla Carvalho
- Arrábida Veterinary Hospital, Arrábida Animal Rehabilitation Center, Setubal, Portugal
| | - Ana Catarina Oliveira
- Arrábida Veterinary Hospital, Arrábida Animal Rehabilitation Center, Setubal, Portugal
- Superior School of Health, Protection and Animal Welfare, Polytechnic Institute of Lusophony, Lisboa, Portugal
| | - António Almeida
- Faculty of Veterinary Medicine, University of Lisbon, Lisboa, Portugal
| | - Óscar Gamboa
- Faculty of Veterinary Medicine, University of Lisbon, Lisboa, Portugal
| | - Lénio Ribeiro
- Faculty of Veterinary Medicine, Lusófona University, Lisboa, Portugal
| | - Mariana Branquinho
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salaza, Universidade do Porto, Porto, Portugal
- Centro de Estudos de Ciência Animal, Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto, Porto, Portugal
- Associate Laboratory for Animal and Veterinary Science (AL4AnimalS), Lisboa, Portugal
| | - Ana Sousa
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salaza, Universidade do Porto, Porto, Portugal
- Centro de Estudos de Ciência Animal, Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto, Porto, Portugal
- Associate Laboratory for Animal and Veterinary Science (AL4AnimalS), Lisboa, Portugal
| | - Bruna Lopes
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salaza, Universidade do Porto, Porto, Portugal
- Centro de Estudos de Ciência Animal, Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto, Porto, Portugal
- Associate Laboratory for Animal and Veterinary Science (AL4AnimalS), Lisboa, Portugal
| | - Patrícia Sousa
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salaza, Universidade do Porto, Porto, Portugal
- Centro de Estudos de Ciência Animal, Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto, Porto, Portugal
- Associate Laboratory for Animal and Veterinary Science (AL4AnimalS), Lisboa, Portugal
| | - Alícia Moreira
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salaza, Universidade do Porto, Porto, Portugal
- Centro de Estudos de Ciência Animal, Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto, Porto, Portugal
- Associate Laboratory for Animal and Veterinary Science (AL4AnimalS), Lisboa, Portugal
| | - André Coelho
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salaza, Universidade do Porto, Porto, Portugal
- Centro de Estudos de Ciência Animal, Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto, Porto, Portugal
- Associate Laboratory for Animal and Veterinary Science (AL4AnimalS), Lisboa, Portugal
| | - Alexandra Rêma
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salaza, Universidade do Porto, Porto, Portugal
- Centro de Estudos de Ciência Animal, Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto, Porto, Portugal
- Associate Laboratory for Animal and Veterinary Science (AL4AnimalS), Lisboa, Portugal
| | - Rui Alvites
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salaza, Universidade do Porto, Porto, Portugal
- Centro de Estudos de Ciência Animal, Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto, Porto, Portugal
- Associate Laboratory for Animal and Veterinary Science (AL4AnimalS), Lisboa, Portugal
- Instituto Universitário de Ciências da Saúde (IUCS), Cooperativa de Ensino Superior Politécnico e Universitário (CESPU), Gandra, Portugal
| | - António Ferreira
- Faculty of Veterinary Medicine, University of Lisbon, Lisboa, Portugal
- Associate Laboratory for Animal and Veterinary Science (AL4AnimalS), Lisboa, Portugal
- CIISA - Centro Interdisciplinar-Investigáo em Saúde Animal, Faculdade de Medicina Veterinária, Av. Universi dade Técnica de Lisboa, Lisboa, Portugal
| | - Ana Colette Maurício
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salaza, Universidade do Porto, Porto, Portugal
- Centro de Estudos de Ciência Animal, Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto, Porto, Portugal
- Associate Laboratory for Animal and Veterinary Science (AL4AnimalS), Lisboa, Portugal
| | - Ângela Martins
- Arrábida Veterinary Hospital, Arrábida Animal Rehabilitation Center, Setubal, Portugal
- Superior School of Health, Protection and Animal Welfare, Polytechnic Institute of Lusophony, Lisboa, Portugal
- Faculty of Veterinary Medicine, Lusófona University, Lisboa, Portugal
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3
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Ascoli GA. Cell morphologies in the nervous system: Glia steal the limelight. J Comp Neurol 2023; 531:338-343. [PMID: 36316800 PMCID: PMC9772107 DOI: 10.1002/cne.25429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 10/12/2022] [Accepted: 10/13/2022] [Indexed: 12/24/2022]
Abstract
Neurons and glia have distinct yet interactive functions but are both characterized by branching morphology. Dendritic trees have been digitally traced for over 40 years in many animal species, anatomical regions, and neuron types. Recently, long-range axons also are being reconstructed throughout the brain of many organisms from invertebrates to primates. In contrast, less attention has been paid until lately to glial morphology. Thus, although glia and neurons are similarly abundant in the nervous systems of humans and most animal models, glia have traditionally been much less represented than neurons in morphological reconstruction repositories such as NeuroMorpho.Org. This is rapidly changing with the advent of high-throughput glia tracing. NeuroMorpho.Org introduced glial cells in 2017 and today they constitute nearly a third of the database content. It took NeuroMorpho.Org 10 years to collect the first 40,000 neurons and now that amount of data can be produced in a single publication. This not only demonstrates the spectacular technological progress in data production, but also demands a corresponding advancement in informatics processing. At the same time, these publicly available data also open new opportunities for quantitative analysis and computational modeling to identify universal or cell-type-specific design principles in the cellular architecture of nervous systems. As a first application, we demonstrated that supervised machine learning of tree geometry classifies neurons and glia with practically perfect accuracy. Furthermore, we discovered a new morphometric biomarker capable of robustly separating these cell classes across multiple species, brain regions, and experimental preparations, with only sparse sampling of branch measurements.
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Affiliation(s)
- Giorgio A. Ascoli
- Center for Neural Informatics, Structures, & Plasticity (CN3), Bioengineering Department, and Neuroscience ProgramGeorge Mason UniversityFairfaxVirginiaUSA
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4
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Deng L, Ravenscraft B, Xu XM. Exploring propriospinal neuron-mediated neural circuit plasticity using recombinant viruses after spinal cord injury. Exp Neurol 2021; 349:113962. [PMID: 34953895 DOI: 10.1016/j.expneurol.2021.113962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 12/16/2021] [Accepted: 12/19/2021] [Indexed: 11/04/2022]
Abstract
Propriospinal neurons (PSNs) play a crucial role in motor control and sensory processing and contribute to plastic reorganization of spinal circuits responsible for recovery from spinal cord injury (SCI). Due to their scattered distribution and various intersegmental projection patterns, it is challenging to dissect the function of PSNs within the neuronal network. New genetically encoded tools, particularly cell-type-specific transgene expression methods using recombinant viral vectors combined with other genetic, pharmacologic, and optogenetic approaches, have enormous potential for visualizing PSNs in the neuronal circuits and monitoring and manipulating their activity. Furthermore, recombinant viral tools have been utilized to promote the intrinsic regenerative capacities of PSNs, towards manipulating the 'hostile' microenvironment for improving functional regeneration of PSNs. Here we summarize the latest development in this fast-moving field and provide a perspective for using this technology to dissect PSN physiological role in contributing to recovery of function after SCI.
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Affiliation(s)
- Lingxiao Deng
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, United States; Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, United States
| | - Baylen Ravenscraft
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, United States
| | - Xiao-Ming Xu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, United States; Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, United States.
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5
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Shinozaki M, Nagoshi N, Nakamura M, Okano H. Mechanisms of Stem Cell Therapy in Spinal Cord Injuries. Cells 2021; 10:cells10102676. [PMID: 34685655 PMCID: PMC8534136 DOI: 10.3390/cells10102676] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 09/28/2021] [Accepted: 10/04/2021] [Indexed: 12/13/2022] Open
Abstract
Every year, 0.93 million people worldwide suffer from spinal cord injury (SCI) with irretrievable sequelae. Rehabilitation, currently the only available treatment, does not restore damaged tissues; therefore, the functional recovery of patients remains limited. The pathophysiology of spinal cord injuries is heterogeneous, implying that potential therapeutic targets differ depending on the time of injury onset, the degree of injury, or the spinal level of injury. In recent years, despite a significant number of clinical trials based on various types of stem cells, these aspects of injury have not been effectively considered, resulting in difficult outcomes of trials. In a specialty such as cancerology, precision medicine based on a patient’s characteristics has brought indisputable therapeutic advances. The objective of the present review is to promote the development of precision medicine in the field of SCI. Here, we first describe the multifaceted pathophysiology of SCI, with the temporal changes after injury, the characteristics of the chronic phase, and the subtypes of complete injury. We then detail the appropriate targets and related mechanisms of the different types of stem cell therapy for each pathological condition. Finally, we highlight the great potential of stem cell therapy in cervical SCI.
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Affiliation(s)
- Munehisa Shinozaki
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan;
| | - Narihito Nagoshi
- Department of Orthopedic Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan; (N.N.); (M.N.)
| | - Masaya Nakamura
- Department of Orthopedic Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan; (N.N.); (M.N.)
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan;
- Correspondence:
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Thermosensitive quaternized chitosan hydrogel scaffolds promote neural differentiation in bone marrow mesenchymal stem cells and functional recovery in a rat spinal cord injury model. Cell Tissue Res 2021; 385:65-85. [PMID: 33760948 DOI: 10.1007/s00441-021-03430-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 01/26/2021] [Indexed: 12/24/2022]
Abstract
A thermosensitive quaternary ammonium chloride chitosan/β-glycerophosphate (HACC/β-GP) hydrogel scaffold combined with bone marrow mesenchymal stem cells (BMSCs) transfected with an adenovirus containing the glial cell-derived neurotrophic factor (GDNF) gene (Ad-rGDNF) was applied to spinal cord injury (SCI) repair. The BMSCs from rats were transfected with Ad-rGDNF, resulting in the expression of GDNF mRNA in the BMSCs increasing and their spontaneous differentiation into neural-like cells expressing neural markers such as NF-200 and GFAP. After incubation with HACC/β-GP hydrogel scaffolds for 2 weeks, neuronal differentiation of the BMSCs was confirmed using immunofluorescence (IF), and the expression of GDNF by the BMSCs was detected by Western blot at different time points. MTT assay and scanning electron microscopy confirmed that the HACC scaffold provides a non-cytotoxic microenvironment that supports cell adhesion and growth. Rats with SCI were treated with BMSCs, BMSCs carried by the HACC/β-GP hydrogel (HACC/BMSCs), Ad-rGDNF-BMSCs, or Ad-rGDNF-BMSCs carried by the hydrogel (HACC/GDNF-BMSCs). Animals were sacrificed at 2, 4, and 6 weeks of treatment. IF staining and Western blot were performed to detect the expression of NeuN, NF-200, GFAP, CS56, and Bax in the lesion sites of the injured spinal cord. Upon treatment with HACC/BMSCs, NF200 and GFAP were upregulated but CS56 and Bax were downregulated in the SCI lesion site. Furthermore, transplantation of HACC/GDNF-BMSCs into an SCI rat model significantly improved BBB scores and regeneration of the spinal cord. Thus, HACC/β-GP hydrogel scaffolds show promise for functional recovery in spinal cord injury patients.
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7
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Brown BL, Zalla RM, Shepard CT, Howard RM, Kopechek JA, Magnuson DSK, Whittemore SR. Dual-Viral Transduction Utilizing Highly Efficient Retrograde Lentivirus Improves Labeling of Long Propriospinal Neurons. Front Neuroanat 2021; 15:635921. [PMID: 33828464 PMCID: PMC8019739 DOI: 10.3389/fnana.2021.635921] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 02/12/2021] [Indexed: 11/13/2022] Open
Abstract
The nervous system coordinates pathways and circuits to process sensory information and govern motor behaviors. Mapping these pathways is important to further understand the connectivity throughout the nervous system and is vital for developing treatments for neuronal diseases and disorders. We targeted long ascending propriospinal neurons (LAPNs) in the rat spinal cord utilizing Fluoro-Ruby (FR) [10kD rhodamine dextran amine (RDA)], and two dual-viral systems. Dual-viral tracing utilizing a retrograde adeno-associated virus (retroAAV), which confers robust labeling in the brain, resulted in a small number of LAPNs being labeled, but dual-viral tracing using a highly efficient retrograde (HiRet) lentivirus provided robust labeling similar to FR. Additionally, dual-viral tracing with HiRet lentivirus and tracing with FR may preferentially label different subpopulations of LAPNs. These data demonstrate that dual-viral tracing in the spinal cord employing a HiRet lentivirus provides robust and specific labeling of LAPNs and emphasizes the need to empirically optimize viral systems to target specific neuronal population(s).
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Affiliation(s)
- Brandon L Brown
- Interdisciplinary Program in Translational Neuroscience, University of Louisville, Louisville, KY, United States.,Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States.,Department of Anatomical Sciences and Neurobiology, School of Medicine, University of Louisville, Louisville, KY, United States
| | - Rachel M Zalla
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States.,Department of Bioengineering, J.B. Speed School of Engineering, University of Louisville, Louisville, KY, United States
| | - Courtney T Shepard
- Interdisciplinary Program in Translational Neuroscience, University of Louisville, Louisville, KY, United States.,Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States.,Department of Anatomical Sciences and Neurobiology, School of Medicine, University of Louisville, Louisville, KY, United States
| | - Russell M Howard
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States.,Department of Neurological Surgery, School of Medicine, University of Louisville, Louisville, KY, United States
| | - Jonathan A Kopechek
- Department of Bioengineering, J.B. Speed School of Engineering, University of Louisville, Louisville, KY, United States
| | - David S K Magnuson
- Interdisciplinary Program in Translational Neuroscience, University of Louisville, Louisville, KY, United States.,Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States.,Department of Anatomical Sciences and Neurobiology, School of Medicine, University of Louisville, Louisville, KY, United States.,Department of Bioengineering, J.B. Speed School of Engineering, University of Louisville, Louisville, KY, United States.,Department of Neurological Surgery, School of Medicine, University of Louisville, Louisville, KY, United States
| | - Scott R Whittemore
- Interdisciplinary Program in Translational Neuroscience, University of Louisville, Louisville, KY, United States.,Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States.,Department of Anatomical Sciences and Neurobiology, School of Medicine, University of Louisville, Louisville, KY, United States.,Department of Neurological Surgery, School of Medicine, University of Louisville, Louisville, KY, United States
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8
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Han Q, Xie Y, Ordaz JD, Huh AJ, Huang N, Wu W, Liu N, Chamberlain KA, Sheng ZH, Xu XM. Restoring Cellular Energetics Promotes Axonal Regeneration and Functional Recovery after Spinal Cord Injury. Cell Metab 2020; 31:623-641.e8. [PMID: 32130884 PMCID: PMC7188478 DOI: 10.1016/j.cmet.2020.02.002] [Citation(s) in RCA: 90] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 11/24/2019] [Accepted: 01/31/2020] [Indexed: 01/30/2023]
Abstract
Axonal regeneration in the central nervous system (CNS) is a highly energy-demanding process. Extrinsic insults and intrinsic restrictions lead to an energy crisis in injured axons, raising the question of whether recovering energy deficits facilitates regeneration. Here, we reveal that enhancing axonal mitochondrial transport by deleting syntaphilin (Snph) recovers injury-induced mitochondrial depolarization. Using three CNS injury mouse models, we demonstrate that Snph-/- mice display enhanced corticospinal tract (CST) regeneration passing through a spinal cord lesion, accelerated regrowth of monoaminergic axons across a transection gap, and increased compensatory sprouting of uninjured CST. Notably, regenerated CST axons form functional synapses and promote motor functional recovery. Administration of the bioenergetic compound creatine boosts CST regenerative capacity in Snph-/- mice. Our study provides mechanistic insights into intrinsic regeneration failure in CNS and suggests that enhancing mitochondrial transport and cellular energetics are promising strategies to promote regeneration and functional restoration after CNS injuries.
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Affiliation(s)
- Qi Han
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Yuxiang Xie
- Synaptic Function Section, The Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Josue D Ordaz
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Andrew J Huh
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Ning Huang
- Synaptic Function Section, The Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Wei Wu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Naikui Liu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Kelly A Chamberlain
- Synaptic Function Section, The Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Zu-Hang Sheng
- Synaptic Function Section, The Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, 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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Propriospinal Neurons of L3-L4 Segments Involved in Control of the Rat External Urethral Sphincter. Neuroscience 2019; 425:12-28. [PMID: 31785359 DOI: 10.1016/j.neuroscience.2019.11.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 10/31/2019] [Accepted: 11/11/2019] [Indexed: 12/17/2022]
Abstract
Coordination of activity of external urethral sphincter (EUS) striated muscle and bladder (BL) smooth muscle is essential for efficient voiding. In this study we examined the morphological and electrophysiological properties of neurons in the L3/L4 spinal cord (SC) that are likely to have an important role in EUS-BL coordination in rats. EUS-related SC neurons were identified by retrograde transsynaptic tracing following injection of pseudorabies virus (PRV) co-expressing fluorescent markers into the EUS of P18-P20 male rats. Tracing revealed not only EUS motoneurons in L6/S1 but also interneurons in lamina X of the L6/S1 and L3/L4 SC. Physiological properties of fluorescently labeled neurons were assessed during whole-cell recordings in SC slices followed by reconstruction of biocytin-filled neurons. Reconstructions of neuronal processes from transverse or longitudinal slices showed that some L3/L4 neurons have axons projecting toward and into the ventro-medial funiculus (VMf) where axons extended caudally. Other neurons had axons projecting within laminae X and VII. Dendrites of L3/L4 neurons were distributed within laminae X and VII. The majority of L3/L4 neurons exhibited tonic firing in response to depolarizing currents. In transverse slices focal electrical stimulation (FES) in the VMf or in laminae X and VII elicited antidromic axonal spikes and/or excitatory synaptic responses in L3/L4 neurons; while in longitudinal slices FES elicited excitatory synaptic inputs from sites up to 400 μm along the central canal. Inhibitory inputs were rarely observed. These data suggest that L3/L4 EUS-related circuitry consists of at least two neuronal populations: segmental interneurons and propriospinal neurons projecting to L6/S1.
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Zhong J, Guo C, Hou W, Shen N, Miao C. Effects of MFHAS1 on cognitive impairment and dendritic pathology in the hippocampus of septic rats. Life Sci 2019; 235:116822. [PMID: 31476310 DOI: 10.1016/j.lfs.2019.116822] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 08/21/2019] [Accepted: 08/29/2019] [Indexed: 01/31/2023]
Abstract
AIMS To investigate the effects of malignant fibrous histiocytoma amplified sequence 1 (MFHAS1) on cognitive dysfunction, the expression of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and amyloid β peptide (Aβ) in the hippocampus, as well as dendritic pathology in the hippocampal CA1 region in sepsis-associated encephalopathy (SAE) rats. MAIN METHODS The rats were randomly divided into four groups: 1) control group (subjected to sham surgery), 2) control plus Mfhas1 siRNA group (rats received intracerebroventricular injection of Mfhas1 siRNA after sham surgery), 3) CLP plus control siRNA group (rats received intracerebroventricular injection of control siRNA after cecal ligation and puncture (CLP)), 4) CLP plus Mfhas1 siRNA group (rats received intracerebroventricular injection of Mfhas1 siRNA after CLP). The learning and memory capabilities of the rats were examined by means of fear conditioning and Barnes maze test. The concentration of TNF-α and IL-1β was determined by enzyme-linked immunosorbent assay. The efficiency of siRNA transfection, MFHAS1 and Aβ expression were detected by Western blotting. Total branch lengths of pyramidal dendrites of the CA1 basilar trees and spine density were determined by Golgi staining. KEY FINDINGS We observed that MFHAS1 knock-down by Mfhas1 siRNA intracerebroventricular injection could improve cognitive impairment, reduce the expression of TNF-α, IL-1β and Aβ in the hippocampus induced by CLP, and alleviate the dendritic spinal loss of the pyramidal neurons, as well as increase the dendritic branching of the CA1 basilar trees of septic rats. SIGNIFICANCE MFHAS1 knock-down can alleviate cognitive impairment, neuroinflammation and dendritic spinal loss in SAE rats.
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Affiliation(s)
- Jing Zhong
- Department of Anesthesiology, Fudan University Shanghai Cancer Center, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Chenyue Guo
- Department of Anesthesiology, Fudan University Shanghai Cancer Center, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Wenting Hou
- Department of Anesthesiology, Fudan University Shanghai Cancer Center, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Na Shen
- Department of Otolaryngology, Zhongshan Hospital, Fudan University, Shanghai, China.
| | - Changhong Miao
- Department of Anesthesiology, Fudan University Shanghai Cancer Center, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.
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11
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Li X, Liu D, Xiao Z, Zhao Y, Han S, Chen B, Dai J. Scaffold-facilitated locomotor improvement post complete spinal cord injury: Motor axon regeneration versus endogenous neuronal relay formation. Biomaterials 2019; 197:20-31. [PMID: 30639547 DOI: 10.1016/j.biomaterials.2019.01.012] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 12/10/2018] [Accepted: 01/05/2019] [Indexed: 01/18/2023]
Abstract
Complete transected spinal cord injury (SCI) severely influences the quality of life and mortality rates of animals and patients. In the past decade, many simple and combinatorial therapeutic treatments have been tested in improving locomotor function in animals with this extraordinarily challenging SCI. The potential mechanism for promotion of locomotor function relies either on direct motor axon regeneration through the lesion gap or indirect neuronal relay bridging to functionally reconnect transected spinal stumps. In this review, we first compare the advantages and problems of complete transection SCI animal models with other prevailing SCI models used in motor axon regeneration research. Next, we enumerate some of the popular bio-scaffolds utilized in complete SCI repair in the last decade. Then, the current state of motor axon regeneration as well as its role on locomotor improvement of animals after complete SCI is discussed. Last, the current approach of directing endogenous neuronal relays formation to achieve motor function recovery by well-designed functional bio-scaffolds implantation in complete transected SCI animals is reviewed. Although facilitating neuronal relays formation by bio-scaffolds implantation appears to be more practical and feasible than directing motor axon regeneration in promoting locomotor outcome in animals after complete SCI, there are still challenges in neuronal relays formation, maintaining and debugging for spinal cord regenerative repair.
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Affiliation(s)
- Xing Li
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China; Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Xiangya Hospital, Central South University (CSU), Changsha, Hunan, 410008, China
| | - Dingyang Liu
- Department of Neurosurgery, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha 410008, Hunan Province, China
| | - Zhifeng Xiao
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yannan Zhao
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Sufang Han
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Bing Chen
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Jianwu Dai
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
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12
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Li J, Li X, Xiao Z, Dai J. [Review of the regeneration mechanism of complete spinal cord injury]. ZHONGGUO XIU FU CHONG JIAN WAI KE ZA ZHI = ZHONGGUO XIUFU CHONGJIAN WAIKE ZAZHI = CHINESE JOURNAL OF REPARATIVE AND RECONSTRUCTIVE SURGERY 2018; 32:641-649. [PMID: 29905039 DOI: 10.7507/1002-1892.201805069] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Spinal cord injury (SCI), especially the complete SCI, usually results in complete paralysis below the level of the injury and seriously affects the patient's quality of life. SCI repair is still a worldwide medical problem. In the last twenty years, Professor DAI Jianwu and his team pioneered complete SCI model by removing spinal tissue with varied lengths in rodents, canine, and non-human primates to verify therapeutic effect of different repair strategies. Moreover, they also started the first clinical study of functional collagen scaffold on patients with acute complete SCI on January 16th, 2015. This review mainly focusses on the possible mechanisms responsible for complete SCI. In common, recovery of some sensory and motor functions post complete SCI include the following three contributing reasons. ① Regeneration of long ascending and descending axons throughout the lesion site to re-connect the original targets; ② New neural circuits formed in the lesion site by newly generated neurons post injury, which effectively re-connect the transected stumps; ③ The combined effect of ① and ②. The numerous studies have confirmed that neural circuits rebuilt across the injury site by newborn neurons might be the main mechanisms for functional recovery of animals from rodents to dogs. In many SCI model, especially the complete spinal cord transection model, many studies have convincingly demonstrated that the quantity and length of regenerated long descending axons, particularly like CST fibers, are too few to across the lesion site that is millimeters in length to realize motor functional recovery. Hence, it is more feasible in guiding neuronal relays formation by bio-scaffolds implantation than directing long motor axons regeneration in improving motor function of animals with complete spinal cord transection. However, some other issues such as promoting more neuronal relays formation, debugging wrong connections, and maintaining adequate neural circuits for functional recovery are urgent problems to be addressed.
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Affiliation(s)
- Jiayin Li
- Institute of Genetics and Development Biology, Chinese Academy of Sciences, Beijing, 100101,P.R.China
| | - Xing Li
- Institute of Genetics and Development Biology, Chinese Academy of Sciences, Beijing, 100101,P.R.China
| | - Zhifeng Xiao
- Institute of Genetics and Development Biology, Chinese Academy of Sciences, Beijing, 100101,P.R.China
| | - Jianwu Dai
- Institute of Genetics and Development Biology, Chinese Academy of Sciences, Beijing, 100101,
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13
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Sengelaub DR, Han Q, Liu NK, Maczuga MA, Szalavari V, Valencia SA, Xu XM. Protective Effects of Estradiol and Dihydrotestosterone following Spinal Cord Injury. J Neurotrauma 2018; 35:825-841. [PMID: 29132243 PMCID: PMC5863086 DOI: 10.1089/neu.2017.5329] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Spinal cord injury (SCI) results in lesions that destroy tissue and disrupt spinal tracts, producing deficits in locomotor and autonomic function. We previously demonstrated that motoneurons and the muscles they innervate show pronounced atrophy after SCI, and these changes are prevented by treatment with testosterone. Here, we assessed whether the testosterone active metabolites estradiol and dihydrotestosterone have similar protective effects after SCI. Young adult female rats received either sham or T9 spinal cord contusion injuries and were treated with estradiol, dihydrotestosterone, both, or nothing via Silastic capsules. Basso-Beattie-Bresnahan locomotor testing was performed weekly and voiding behavior was assessed at 3 weeks post-injury. Four weeks after SCI, lesion volume and tissue sparing, quadriceps muscle fiber cross-sectional area, and motoneuron dendritic morphology were assessed. Spontaneous locomotor behavior improved after SCI, but hormone treatments had no effect. Voiding behavior was disrupted after SCI, but was significantly improved by treatment with either estradiol or dihydrotestosterone; combined treatment was maximally effective. Treatment with estradiol reduced lesion volume, but dihydrotestosterone alone and estradiol combined with dihydrotestosterone were ineffective. SCI-induced decreases in motoneuron dendritic length were attenuated by all hormone treatments. SCI-induced reductions in muscle fiber cross-sectional areas were prevented by treatment with either dihydrotestosterone or estradiol combined with dihydrotestosterone, but estradiol treatment was ineffective. These findings suggest that deficits in micturition and regressive changes in motoneuron and muscle morphology seen after SCI are ameliorated by treatment with estradiol or dihydrotestosterone, further supporting a role for steroid hormones as neurotherapeutic agents in the injured nervous system.
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Affiliation(s)
- Dale R. Sengelaub
- Psychological and Brain Sciences, Indiana University, Bloomington, Indiana
| | - Qi Han
- Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, Indiana
| | - Nai-Kui Liu
- Department of Neurological Surgery, Indiana University School of Medicine, Indianapolis, Indiana
| | - Melissa A. Maczuga
- Psychological and Brain Sciences, Indiana University, Bloomington, Indiana
| | - Violetta Szalavari
- Psychological and Brain Sciences, Indiana University, Bloomington, Indiana
| | | | - Xiao-Ming Xu
- Spinal Cord and Brain Injury Research Group, Indiana University School of Medicine, Indianapolis, Indiana
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Chen J, Wang Z, Zheng Z, Chen Y, Khor S, Shi K, He Z, Wang Q, Zhao Y, Zhang H, Li X, Li J, Yin J, Wang X, Xiao J. Neuron and microglia/macrophage-derived FGF10 activate neuronal FGFR2/PI3K/Akt signaling and inhibit microglia/macrophages TLR4/NF-κB-dependent neuroinflammation to improve functional recovery after spinal cord injury. Cell Death Dis 2017; 8:e3090. [PMID: 28981091 PMCID: PMC5682656 DOI: 10.1038/cddis.2017.490] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 08/07/2017] [Accepted: 08/28/2017] [Indexed: 01/09/2023]
Abstract
Therapeutics used to treat central nervous system (CNS) injury were designed to repair neurites and inhibit cell apoptosis. Previous studies have shown that neuron-derived FGF10 exerts potential neuroprotective effects after cerebral ischemia injury. However, little is known about the role of endogenous FGF10 in the recovery process after spinal cord injury (SCI). In this study, we found that FGF10 is mainly produced by neuron and microglia/macrophages, and its expression is increased after SCI. Exogenous treatment of FGF10 improved functional recovery after injury by reducing apoptosis, as well as repairing neurites via FGFR2/PI3K/Akt pathway. On another hand, inhibiting the PI3K/Akt pathway with LY294002 partially reversed the therapeutic effects of FGF10. In addition, small interfering RNA knockdown of FGFR2 suppressed PI3K/Akt pathway activation by FGF10 and abolished its anti-apoptotic and neurite repair effects in vitro. Furthermore, FGF10 treatment inhibited the activation and proliferation of microglia/macrophages through regulation of TLR4/NF-κB pathway, and attenuated the release of pro-inflammatory cytokines after SCI. Thus, the increased expression of FGF10 after acute SCI is an endogenous self-protective response, suggesting that FGF10 could be a potential treatment for CNS injury.
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Affiliation(s)
- Jian Chen
- Department of Orthopaedic Surgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Zhouguang Wang
- Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, China
| | - ZengMing Zheng
- Department of Orthopaedic Surgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China.,Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, China
| | - Yu Chen
- Department of Orthopaedic Surgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Sinan Khor
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - KeSi Shi
- Department of Orthopaedic Surgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - ZiLi He
- Department of Orthopaedic Surgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Qingqing Wang
- Department of Orthopaedic Surgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Yingzheng Zhao
- Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, China
| | - Hongyu Zhang
- Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, China
| | - Xiaokun Li
- Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, China
| | - Jiawei Li
- Department of Orthopaedic Surgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Jiayu Yin
- Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, China
| | - Xiangyang Wang
- Department of Orthopaedic Surgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Jian Xiao
- Department of Orthopaedic Surgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China.,Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, China
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15
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Haque A, Capone M, Matzelle D, Cox A, Banik NL. Targeting Enolase in Reducing Secondary Damage in Acute Spinal Cord Injury in Rats. Neurochem Res 2017; 42:2777-2787. [PMID: 28508172 DOI: 10.1007/s11064-017-2291-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 04/24/2017] [Accepted: 05/06/2017] [Indexed: 12/12/2022]
Abstract
Spinal cord injury (SCI) is a complex debilitating condition leading to permanent life-long neurological deficits. The complexity of SCI suggests that a concerted multi-targeted therapeutic approach is warranted to optimally improve function. Damage to spinal cord is complicated by an increased detrimental response from secondary injury factors mediated by activated glial cells and infiltrating macrophages. While elevation of enolase especially neuron specific enolase (NSE) in glial and neuronal cells is believed to trigger inflammatory cascades in acute SCI, alteration of NSE and its subsequent effects in acute SCI remains unknown. This study measured NSE expression levels and key inflammatory mediators after acute SCI and investigated the role of ENOblock, a novel small molecule inhibitor of enolase, in a male Sprague-Dawley (SD) rat SCI model. Serum NSE levels as well as cytokines/chemokines and metabolic factors were evaluated in injured animals following treatment with vehicle alone or ENOblock using Discovery assay. Spinal cord samples were also analyzed for NSE and MMPs 2 and 9 as well as glial markers by Western blotting. The results indicated a significant decrease in serum inflammatory cytokines/chemokines and NSE, alterations of metabolic factors and expression of MMPs in spinal cord tissues after treatment with ENOblock (100 µg/kg, twice). These results support the hypothesis that activation of glial cells and inflammation status can be modulated by regulation of NSE expression and activity. Analysis of SCI tissue samples by immunohistochemistry confirmed that ENOblock decreased gliosis which may have occurred through reduction of elevated NSE in rats. Overall, elevation of NSE is deleterious as it promotes extracellular degradation and production of inflammatory cytokines/chemokines and metabolic factors which activates glia and damages neurons. Thus, reduction of NSE by ENOblock may have potential therapeutic implications in acute SCI.
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Affiliation(s)
- Azizul Haque
- Department of Microbiology and Immunology, Medical University of South Carolina, 173 Ashley Avenue, BSB-201, Charleston, SC, 29425, USA.
| | - Mollie Capone
- Department of Microbiology and Immunology, Medical University of South Carolina, 173 Ashley Avenue, BSB-201, Charleston, SC, 29425, USA
- Ralph H. Johnson Veterans Administration Medical Center, Charleston, SC, USA
| | - Denise Matzelle
- Department of Neurosurgery, Medical University of South Carolina, Charleston, USA
- Ralph H. Johnson Veterans Administration Medical Center, Charleston, SC, USA
| | - April Cox
- FirstString Research, Mt. Pleasant, SC, USA
| | - Naren L Banik
- Department of Microbiology and Immunology, Medical University of South Carolina, 173 Ashley Avenue, BSB-201, Charleston, SC, 29425, USA
- Department of Neurosurgery, Medical University of South Carolina, Charleston, USA
- Ralph H. Johnson Veterans Administration Medical Center, Charleston, SC, USA
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