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Yao L, Sai HV, Shippy T, Li B. Cellular and Transcriptional Response of Human Astrocytes to Hybrid Protein Materials. ACS APPLIED BIO MATERIALS 2024; 7:2887-2898. [PMID: 38632900 DOI: 10.1021/acsabm.3c01266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2024]
Abstract
Collagen is a major component of the tissue matrix, and soybean can regulate the tissue immune response. Both materials have been used to fabricate biomaterials for tissue repair. In this study, adult and fetal human astrocytes were grown in a soy protein isolate (SPI)-collagen hybrid gel or on the surface of a cross-linked SPI-collagen membrane. Hybrid materials reduced the cell proliferation rate compared to materials generated by collagen alone. However, the hybrid materials did not significantly change the cell motility compared to the control collagen material. RNA-sequencing (RNA-Seq) analysis showed downregulated genes in the cell cycle pathway, including CCNA2, CCNB1, CCNB2, CCND1, CCND2, and CDK1, which may explain lower cell proliferation in the hybrid material. This study also revealed the downregulation of genes encoding extracellular matrix (ECM) components, including HSPG2, LUM, SDC2, COL4A1, COL4A5, COL4A6, and FN1, as well as genes encoding chemokines, including CCL2, CXCL1, CXCL2, CX3CL1, CXCL3, and LIF, for adult human astrocytes grown on the hybrid membrane compared with those grown on the control collagen membrane. The study explored the cellular and transcriptional responses of human astrocytes to the hybrid material and indicated a potential beneficial function of the material in the application of neural repair.
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Affiliation(s)
- Li Yao
- Department of Biological Sciences, Wichita State University, 1845 Fairmount Street, Wichita, Kansas 67260, United States
| | - Haneesha Vishwa Sai
- Department of Biological Sciences, Wichita State University, 1845 Fairmount Street, Wichita, Kansas 67260, United States
| | - Teresa Shippy
- KSU Bioinformatics Center, Division of Biology, Kansas State University, Manhattan, Kansas 66506, United States
| | - Bin Li
- Department of Mechanical Engineering, Wichita State University, 1845 Fairmount Street, Wichita, Kansas 67260, United States
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Mohammed Butt A, Rupareliya V, Hariharan A, Kumar H. Building a pathway to recovery: Targeting ECM remodeling in CNS injuries. Brain Res 2023; 1819:148533. [PMID: 37586675 DOI: 10.1016/j.brainres.2023.148533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 08/07/2023] [Accepted: 08/09/2023] [Indexed: 08/18/2023]
Abstract
Extracellular matrix (ECM) is a complex and dynamic network of proteoglycans, proteins, and other macromolecules that surrounds cells in tissues. The ECM provides structural support to cells and plays a critical role in regulating various cellular functions. ECM remodeling is a dynamic process involving the breakdown and reconstruction of the ECM. This process occurs naturally during tissue growth, wound healing, and tissue repair. However, in the context of central nervous system (CNS) injuries, dysregulated ECM remodeling can lead to the formation of fibrotic and glial scars. CNS injuries encompass various traumatic events, including concussions and fractures. Following CNS trauma, the formation of glial and fibrotic scars becomes prominent. Glial scars primarily consist of reactive astrocytes, while fibrotic scars are characterized by an abundance of ECM proteins. ECM remodeling plays a pivotal and tightly regulated role in the development of these scars after spinal cord and brain injuries. Various factors like ECM components, ECM remodeling enzymes, cell surface receptors of ECM molecules, and downstream pathways of ECM molecules are responsible for the remodeling of the ECM. The aim of this review article is to explore the changes in ECM during normal physiological conditions and following CNS injuries. Additionally, we discuss various approaches that target various factors responsible for ECM remodeling, with a focus on promoting axon regeneration and functional recovery after CNS injuries. By targeting ECM remodeling, it may be possible to enhance axonal regeneration and facilitate functional recovery after CNS injuries.
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Affiliation(s)
- Ayub Mohammed Butt
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Ahmedabad, Gandhinagar, Gujarat, India
| | - Vimal Rupareliya
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Ahmedabad, Gandhinagar, Gujarat, India
| | - A Hariharan
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Ahmedabad, Gandhinagar, Gujarat, India
| | - Hemant Kumar
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Ahmedabad, Gandhinagar, Gujarat, India.
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Abstract
Iron accumulation in the CNS occurs in many neurological disorders. It can contribute to neuropathology as iron is a redox-active metal that can generate free radicals. The reasons for the iron buildup in these conditions are varied and depend on which aspects of iron influx, efflux, or sequestration that help maintain iron homeostasis are dysregulated. Iron was shown recently to induce cell death and damage via lipid peroxidation under conditions in which there is deficient glutathione-dependent antioxidant defense. This form of cell death is called ferroptosis. Iron chelation has had limited success in the treatment of neurological disease. There is therefore much interest in ferroptosis as it potentially offers new drugs that could be more effective in reducing iron-mediated lipid peroxidation within the lipid-rich environment of the CNS. In this review, we focus on the molecular mechanisms that induce ferroptosis. We also address how iron enters and leaves the CNS, as well as the evidence for ferroptosis in several neurological disorders. Finally, we highlight biomarkers of ferroptosis and potential therapeutic strategies.
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Affiliation(s)
- Samuel David
- Centre for Research in Neuroscience, and BRaIN Program, Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - Fari Ryan
- Centre for Research in Neuroscience, and BRaIN Program, Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - Priya Jhelum
- Centre for Research in Neuroscience, and BRaIN Program, Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - Antje Kroner
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI, USA
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Danilov CA, Thein TZ, Tahara SM, Schönthal AH, Chen TC. Intranasal Delivery of miR133b in a NEO100-Based Formulation Induces a Healing Response in Spinal Cord-Injured Mice. Cells 2023; 12:931. [PMID: 36980272 PMCID: PMC10047048 DOI: 10.3390/cells12060931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 02/10/2023] [Accepted: 03/15/2023] [Indexed: 03/30/2023] Open
Abstract
Despite important advances in the pre-clinical animal studies investigating the neuroinhibitory microenvironment at the injury site, traumatic injury to the spinal cord remains a major problem with no concrete response. Here, we examined whether (1) intranasal (IN) administration of miR133b/Ago2 can reach the injury site and achieve a therapeutic effect and (2) NEO100-based formulation of miR133b/Ago2 can improve effectiveness. 24 h after a cervical contusion, C57BL6 female mice received IN delivery of miR133b/Ago2 or miR133b/Ago2/NEO100 for 3 days, one dose per day. The pharmacokinetics of miR133b in the spinal cord lesion was determined by RT-qPCR. The role of IN delivery of miR133b on motor function was assessed by the grip strength meter (GSM) and hanging tasks. The activity of miR133b at the lesion site was established by immunostaining of fibronectin 1 (FN1), a miR133b target. We found that IN delivery of miR133b/Ago2 (1) reaches the lesion scar and co-administration of miR133b with NEO100 facilitated the cellular uptake; (2) enhanced the motor function and addition of NEO100 potentiated this effect and (3) targeted FN1 expression at the lesion scar. Our results suggest a high efficacy of IN delivery of miR133b/Ago2 to the injured spinal cord that translates to improved healing with NEO100 further potentiating this effect.
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Affiliation(s)
- Camelia A. Danilov
- Department of Neurological Surgery, University of Southern California, Los Angeles, CA 90033, USA; (C.A.D.)
| | - Thu Zan Thein
- Department of Neurological Surgery, University of Southern California, Los Angeles, CA 90033, USA; (C.A.D.)
| | - Stanley M. Tahara
- Department of Molecular Microbiology and Immunology, University of Southern California, Los Angeles, CA 90033, USA
| | - Axel H. Schönthal
- Department of Molecular Microbiology and Immunology, University of Southern California, Los Angeles, CA 90033, USA
| | - Thomas C. Chen
- Department of Neurological Surgery, University of Southern California, Los Angeles, CA 90033, USA; (C.A.D.)
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Griffin JM, Hingorani Jai Prakash S, Bockemühl T, Benner JM, Schaffran B, Moreno-Manzano V, Büschges A, Bradke F. Rehabilitation enhances epothilone-induced locomotor recovery after spinal cord injury. Brain Commun 2023; 5:fcad005. [PMID: 36744011 PMCID: PMC9893225 DOI: 10.1093/braincomms/fcad005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 10/21/2022] [Accepted: 01/12/2023] [Indexed: 01/15/2023] Open
Abstract
Microtubule stabilization through epothilones is a promising preclinical therapy for functional recovery following spinal cord injury that stimulates axon regeneration, reduces growth-inhibitory molecule deposition and promotes functional improvements. Rehabilitation therapy is the only clinically validated approach to promote functional improvements following spinal cord injury. However, whether microtubule stabilization can augment the beneficial effects of rehabilitation therapy or act in concert with it to further promote repair remains unknown. Here, we investigated the pharmacokinetic, histological and functional efficacies of epothilone D, epothilone B and ixabepilone alone or in combination with rehabilitation following a moderate contusive spinal cord injury. Pharmacokinetic analysis revealed that ixabepilone only weakly crossed the blood-brain barrier and was subsequently excluded from further investigations. In contrast, epothilones B and D rapidly distributed to CNS compartments displaying similar profiles after either subcutaneous or intraperitoneal injections. Following injury and subcutaneous administration of epothilone B or D, rats were subjected to 7 weeks of sequential bipedal and quadrupedal training. For all outcome measures, epothilone B was efficacious compared with epothilone D. Specifically, epothilone B decreased fibrotic scaring which was associated with a retention of fibronectin localized to perivascular cells in sections distal to the lesion. This corresponded to a decreased number of cells present within the intralesional space, resulting in less axons within the lesion. Instead, epothilone B increased serotonergic fibre regeneration and vesicular glutamate transporter 1 expression caudal to the lesion, which was not affected by rehabilitation. Multiparametric behavioural analyses consisting of open-field locomotor scoring, horizontal ladder, catwalk gait analysis and hindlimb kinematics revealed that rehabilitation and epothilone B both improved several aspects of locomotion. Specifically, rehabilitation improved open-field locomotor and ladder scores, as well as improving the gait parameters of limb coupling, limb support, stride length and limb speed; epothilone B improved these same gait parameters but also hindlimb kinematic profiles. Functional improvements by epothilone B and rehabilitation acted complementarily on gait parameters leading to an enhanced recovery in the combination group. As a result, principal component analysis of gait showed the greatest improvement in the epothilone B plus rehabilitation group. Thus, these results support the combination of epothilone B with rehabilitation in a clinical setting.
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Affiliation(s)
- Jarred M Griffin
- Correspondence may also be addressed to: Jarred Griffin The German Center for Neurodegenerative Diseases (DZNE) Venusberg-Campus 1/99, Bonn 53127, Germany E-mail:
| | - Sonia Hingorani Jai Prakash
- Neuronal and Tissue Regeneration Laboratory, Centro de Investigación Príncipe Felipe (CIPF), Valencia 46012, Spain
| | - Till Bockemühl
- Department of Animal Physiology, Institute of Zoology, University of Cologne, Cologne 50674, Germany
| | - Jessica M Benner
- Laboratory for Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases (DZNE), Bonn 53127, Germany
| | - Barbara Schaffran
- Laboratory for Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases (DZNE), Bonn 53127, Germany
| | - Victoria Moreno-Manzano
- Neuronal and Tissue Regeneration Laboratory, Centro de Investigación Príncipe Felipe (CIPF), Valencia 46012, Spain
| | - Ansgar Büschges
- Department of Animal Physiology, Institute of Zoology, University of Cologne, Cologne 50674, Germany
| | - Frank Bradke
- Correspondence to: Frank Bradke The German Center for Neurodegenerative Diseases (DZNE) Venusberg-Campus 1/99, Bonn 53127, Germany E-mail:
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Dynamic changes in mechanical properties of the adult rat spinal cord after injury. Acta Biomater 2023; 155:436-448. [PMID: 36435440 DOI: 10.1016/j.actbio.2022.11.041] [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: 08/04/2022] [Revised: 11/06/2022] [Accepted: 11/18/2022] [Indexed: 11/25/2022]
Abstract
Spinal cord injury (SCI), a debilitating medical condition that can cause irreversible loss of neurons and permanent paralysis, currently has no cure. However, regenerative medicine may offer a promising treatment. Given that numerous regenerative strategies aim to deliver cells and materials in the form of tissue-engineered therapies, understanding and characterising the mechanical properties of the spinal cord tissue is very important. In this study, we have systematically characterised the spatiotemporal changes in elastic stiffness (elastic modulus, Pa) and viscosity (drop in peak force, %) of injured rat thoracic spinal cord tissues at distinct time points after crush injury using the indentation technique. Our results demonstrate that in comparison with uninjured spinal cord tissue, the injured tissues exhibited lower stiffness (median 3281 Pa versus 9632 Pa; P < 0.001) but demonstrated elevated viscosity (median 80% versus 57%; P < 0.001) at 3 days postinjury. Between 4 and 6 weeks after SCI, the overall viscoelastic properties of injured tissues returned to baseline values. At 12 weeks after SCI, in comparison with uninjured tissue, the injured spinal cord tissues displayed a significant increase in both elasticity (median 13698 Pa versus 9920 Pa; P < 0.001) and viscosity (median 64% versus 58%; P < 0.001). This work constitutes the first quantitative mapping of spatiotemporal changes in spinal cord tissue elasticity and viscosity in injured rats, providing a mechanical basis of the tissue for future studies on the development of biomaterials for SCI repair. STATEMENT OF SIGNIFICANCE: Spinal cord injury (SCI) is a devastating disease often leading to permanent paralysis. While enormous progress in understanding the molecular pathomechanisms of SCI has been made, the mechanical properties of injured spinal cord tissue have received considerably less attention. This study provides systematic characterization of the biomechanical evolution of rat spinal cord tissue after SCI using a microindentation test method. We find spinal cord tissue behaves significantly softer but more viscous immediately postinjury. As time passes, the lesion site gradually returns to baseline values and then displays pronounced increased viscoelastic properties. As host tissue mechanical properties are a crucial consideration for any biomaterial implanted into central nervous system, our results may have important implications for further studies of SCI repair.
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Fibrotic Scar in CNS Injuries: From the Cellular Origins of Fibroblasts to the Molecular Processes of Fibrotic Scar Formation. Cells 2022; 11:cells11152371. [PMID: 35954214 PMCID: PMC9367779 DOI: 10.3390/cells11152371] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 07/29/2022] [Accepted: 07/30/2022] [Indexed: 02/06/2023] Open
Abstract
Central nervous system (CNS) trauma activates a persistent repair response that leads to fibrotic scar formation within the lesion. This scarring is similar to other organ fibrosis in many ways; however, the unique features of the CNS differentiate it from other organs. In this review, we discuss fibrotic scar formation in CNS trauma, including the cellular origins of fibroblasts, the mechanism of fibrotic scar formation following an injury, as well as the implication of the fibrotic scar in CNS tissue remodeling and regeneration. While discussing the shared features of CNS fibrotic scar and fibrosis outside the CNS, we highlight their differences and discuss therapeutic targets that may enhance regeneration in the CNS.
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Li Z, Yu S, Liu Y, Hu X, Li Y, Xiao Z, Chen Y, Tian D, Xu X, Cheng L, Zheng M, Jing J. SU16f inhibits fibrotic scar formation and facilitates axon regeneration and locomotor function recovery after spinal cord injury by blocking the PDGFRβ pathway. J Neuroinflammation 2022; 19:95. [PMID: 35429978 PMCID: PMC9013464 DOI: 10.1186/s12974-022-02449-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Accepted: 03/28/2022] [Indexed: 11/19/2022] Open
Abstract
Background Excessively deposited fibrotic scar after spinal cord injury (SCI) inhibits axon regeneration. It has been reported that platelet-derived growth factor receptor beta (PDGFRβ), as a marker of fibrotic scar-forming fibroblasts, can only be activated by platelet-derived growth factor (PDGF) B or PDGFD. However, whether the activation of the PDGFRβ pathway can mediate fibrotic scar formation after SCI remains unclear. Methods A spinal cord compression injury mouse model was used. In situ injection of exogenous PDGFB or PDGFD in the spinal cord was used to specifically activate the PDGFRβ pathway in the uninjured spinal cord, while intrathecal injection of SU16f was used to specifically block the PDGFRβ pathway in the uninjured or injured spinal cord. Immunofluorescence staining was performed to explore the distributions and cell sources of PDGFB and PDGFD, and to evaluate astrocytic scar, fibrotic scar, inflammatory cells and axon regeneration after SCI. Basso Mouse Scale (BMS) and footprint analysis were performed to evaluate locomotor function recovery after SCI. Results We found that the expression of PDGFD and PDGFB increased successively after SCI, and PDGFB was mainly secreted by astrocytes, while PDGFD was mainly secreted by macrophages/microglia and fibroblasts. In addition, in situ injection of exogenous PDGFB or PDGFD can lead to fibrosis in the uninjured spinal cord, while this profibrotic effect could be specifically blocked by the PDGFRβ inhibitor SU16f. We then treated the mice after SCI with SU16f and found the reduction of fibrotic scar, the interruption of scar boundary and the inhibition of lesion and inflammation, which promoted axon regeneration and locomotor function recovery after SCI. Conclusions Our study demonstrates that activation of PDGFRβ pathway can directly induce fibrotic scar formation, and specific blocking of this pathway would contribute to the treatment of SCI.
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Li SY, Johnson R, Smyth LC, Dragunow M. Platelet-derived growth factor signalling in neurovascular function and disease. Int J Biochem Cell Biol 2022; 145:106187. [PMID: 35217189 DOI: 10.1016/j.biocel.2022.106187] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Revised: 02/08/2022] [Accepted: 02/21/2022] [Indexed: 11/25/2022]
Abstract
Platelet-derived growth factors are critical for cerebrovascular development and homeostasis. Abnormalities in this signalling pathway are implicated in neurological diseases, especially those where neurovascular dysfunction and neuroinflammation plays a prominent role in disease pathologies, such as stroke and Alzheimer's disease; the angiogenic nature of this pathway also draws its significance in brain malignancies such as glioblastoma where tumour angiogenesis is profuse. In this review, we provide an updated overview of the actions of the platelet-derived growth factors on neurovascular function, their role in the regulation of perivascular cell types expressing the cognate receptors, neurological diseases associated with aberrance in signalling, and highlight the clinical relevance and therapeutic potentials of this pathway for central nervous system diseases.
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Affiliation(s)
- Susan Ys Li
- Department of Pharmacology and Centre for Brain Research, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand.
| | - Rebecca Johnson
- Department of Pharmacology and Centre for Brain Research, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand.
| | - Leon Cd Smyth
- Center for Brain Immunology and Glia, Department of Pathology and Immunology, Washington University in St Louis, MO, USA.
| | - Mike Dragunow
- Department of Pharmacology and Centre for Brain Research, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand.
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Zou Y, Yin Y, Xiao Z, Zhao Y, Han J, Chen B, Xu B, Cui Y, Ma X, Dai J. Transplantation of collagen sponge-based three-dimensional neural stem cells cultured in a RCCS facilitates locomotor functional recovery in spinal cord injury animals. Biomater Sci 2022; 10:915-924. [PMID: 35044381 DOI: 10.1039/d1bm01744f] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Numerous studies have indicated that microgravity induces various changes in the cellular functions of neural stem cells (NSCs), and the use of microgravity to culture tissue engineered seed cells for the treatment of nervous system diseases has drawn increasing attention. The goal of this study was to verify the efficacy of collagen sponge-based 3-dimensional (3D) NSCs cultured in a rotary cell culture system (RCCS) in treating spinal cord injury (SCI). The Basso-Beattie-Bresnahan score, inclined plane test, and electrophysiology results all indicated that 3D cultured NSCs cultured in a RCCS had better therapeutic effects than those cultured in a traditional cell culture environment, suggesting that the microgravity provided by the RCCS could enhance the therapeutic effect of 3D cultured NSCs. Our study indicates the feasibility of combining the RCCS with collagen sponge-based 3D cell culture for producing tissue engineered seed cells for the treatment of SCI. This novel and effective method shows promise for application in cell-based therapy for SCI in the future.
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Affiliation(s)
- Yunlong Zou
- China-Japan Union Hospital of Jilin University, 126 Xiantai Street, Changchun 130033, China
| | - Yanyun Yin
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 3 Nanyitiao, Zhongguancun, Beijing 100101, China.
| | - Zhifeng Xiao
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 3 Nanyitiao, Zhongguancun, Beijing 100101, China.
| | - Yannan Zhao
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 3 Nanyitiao, Zhongguancun, Beijing 100101, China.
| | - Jin Han
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 3 Nanyitiao, Zhongguancun, Beijing 100101, China.
| | - Bing Chen
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 3 Nanyitiao, Zhongguancun, Beijing 100101, China.
| | - Bai Xu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 3 Nanyitiao, Zhongguancun, Beijing 100101, China.
| | - Yi Cui
- Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100080, China.
| | - Xu Ma
- Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100080, China.
| | - Jianwu Dai
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 3 Nanyitiao, Zhongguancun, Beijing 100101, China.
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Abstract
Recent transcriptomic, histological and functional studies have begun to shine light on the fibroblasts present in the meninges, choroid plexus and perivascular spaces of the brain and spinal cord. Although the origins and functions of CNS fibroblasts are still being described, it is clear that they represent a distinct cell population, or populations, that have likely been confused with other cell types on the basis of the expression of overlapping cellular markers. Recent work has revealed that fibroblasts play crucial roles in fibrotic scar formation in the CNS after injury and inflammation, which have also been attributed to other perivascular cell types such as pericytes and vascular smooth muscle cells. In this Review, we describe the current knowledge of the location and identity of CNS perivascular cell types, with a particular focus on CNS fibroblasts, including their origin, subtypes, roles in health and disease, and future areas for study.
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12
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Li Z, Yu S, Hu X, Li Y, You X, Tian D, Cheng L, Zheng M, Jing J. Fibrotic Scar After Spinal Cord Injury: Crosstalk With Other Cells, Cellular Origin, Function, and Mechanism. Front Cell Neurosci 2021; 15:720938. [PMID: 34539350 PMCID: PMC8441597 DOI: 10.3389/fncel.2021.720938] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Accepted: 07/28/2021] [Indexed: 01/18/2023] Open
Abstract
The failure of axonal regeneration after spinal cord injury (SCI) results in permanent loss of sensorimotor function. The persistent presence of scar tissue, mainly fibrotic scar and astrocytic scar, is a critical cause of axonal regeneration failure and is widely accepted as a treatment target for SCI. Astrocytic scar has been widely investigated, while fibrotic scar has received less attention. Here, we review recent advances in fibrotic scar formation and its crosstalk with other main cellular components in the injured core after SCI, as well as its cellular origin, function, and mechanism. This study is expected to provide an important basis and novel insights into fibrotic scar as a treatment target for SCI.
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Affiliation(s)
- Ziyu Li
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
| | - Shuisheng Yu
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
| | - Xuyang Hu
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
| | - Yiteng Li
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
| | - Xingyu You
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
| | - Dasheng Tian
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
| | - Li Cheng
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
| | - Meige Zheng
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
| | - Juehua Jing
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
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13
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Mutoji KN, Sun M, Nash A, Puri S, Hascall V, Coulson-Thomas VJ. Anti-inflammatory protein TNFα-stimulated gene-6 (TSG-6) reduces inflammatory response after brain injury in mice. BMC Immunol 2021; 22:52. [PMID: 34348643 PMCID: PMC8336266 DOI: 10.1186/s12865-021-00443-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 07/09/2021] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Current research suggests that the glial scar surrounding penetrating brain injuries is instrumental in preserving the surrounding uninjured tissue by limiting the inflammatory response to the injury site. We recently showed that tumor necrosis factor (TNF)-stimulated gene-6 (TSG-6), a well-established anti-inflammatory molecule, is present within the glial scar. In the present study we investigated the role of TSG-6 within the glial scar using TSG-6 null and littermate control mice subjected to penetrating brain injuries. RESULTS Our findings show that mice lacking TSG-6 present a more severe inflammatory response after injury, which was correlated with an enlarged area of astrogliosis beyond the injury site. CONCLUSION Our data provides evidence that TSG-6 has an anti-inflammatory role within the glial scar.
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Affiliation(s)
- Kazadi Nadine Mutoji
- College of Optometry, University of Houston, 4901 Calhoun Road, Houston, TX, 77204-2020, USA
| | - Mingxia Sun
- College of Optometry, University of Houston, 4901 Calhoun Road, Houston, TX, 77204-2020, USA
| | - Amanda Nash
- College of Optometry, University of Houston, 4901 Calhoun Road, Houston, TX, 77204-2020, USA
- Department of Bioengineering, Rice University, Houston, TX, 77030, USA
| | - Sudan Puri
- College of Optometry, University of Houston, 4901 Calhoun Road, Houston, TX, 77204-2020, USA
| | | | - Vivien J Coulson-Thomas
- College of Optometry, University of Houston, 4901 Calhoun Road, Houston, TX, 77204-2020, USA.
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14
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Tsata V, Wehner D. Know How to Regrow-Axon Regeneration in the Zebrafish Spinal Cord. Cells 2021; 10:cells10061404. [PMID: 34204045 PMCID: PMC8228677 DOI: 10.3390/cells10061404] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 05/25/2021] [Accepted: 06/04/2021] [Indexed: 12/14/2022] Open
Abstract
The capacity for long-distance axon regeneration and functional recovery after spinal cord injury is poor in mammals but remarkable in some vertebrates, including fish and salamanders. The cellular and molecular basis of this interspecies difference is beginning to emerge. This includes the identification of target cells that react to the injury and the cues directing their pro-regenerative responses. Among existing models of successful spinal cord regeneration, the zebrafish is arguably the most understood at a mechanistic level to date. Here, we review the spinal cord injury paradigms used in zebrafish, and summarize the breadth of neuron-intrinsic and -extrinsic factors that have been identified to play pivotal roles in the ability of zebrafish to regenerate central nervous system axons and recover function.
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Affiliation(s)
- Vasiliki Tsata
- Experimental Surgery, Clinical and Translational Research Center, Biomedical Research Foundation Academy of Athens, 11527 Athens, Greece
- Correspondence: (V.T.); (D.W.)
| | - Daniel Wehner
- Max Planck Institute for the Science of Light, 91058 Erlangen, Germany
- Max-Planck-Zentrum für Physik und Medizin, 91058 Erlangen, Germany
- Correspondence: (V.T.); (D.W.)
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Xu L, Yao Y. Central Nervous System Fibroblast-Like Cells in Stroke and Other Neurological Disorders. Stroke 2021; 52:2456-2464. [PMID: 33940953 DOI: 10.1161/strokeaha.120.033431] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Fibroblasts are the most common cell type of connective tissues. In the central nervous system (CNS), fibroblast-like cells are mainly located in the meninges and perivascular Virchow-Robin space. The origins of these fibroblast-like cells and their functions in both CNS development and pathological conditions remain largely unknown. In this review, we first introduce the anatomic location and molecular markers of CNS fibroblast-like cells. Next, the functions of fibroblast-like cells in CNS development and neurological disorders, including stroke, CNS traumatic injuries, and other neurological diseases, are discussed. Third, current challenges and future directions in the field are summarized. We hope to provide a synthetic review that stimulates future research on CNS fibroblast-like cells.
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Affiliation(s)
- Lingling Xu
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens
| | - Yao Yao
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens
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Li Z, Zheng M, Yu S, Yao F, Luo Y, Liu Y, Tian D, Cheng L, Jing J. M2 Macrophages Promote PDGFRβ + Pericytes Migration After Spinal Cord Injury in Mice via PDGFB/PDGFRβ Pathway. Front Pharmacol 2021; 12:670813. [PMID: 33935795 PMCID: PMC8082415 DOI: 10.3389/fphar.2021.670813] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 03/22/2021] [Indexed: 01/06/2023] Open
Abstract
Platelet derived growth factor receptor β positive (PDGFRβ+) pericytes form fibrotic scar, which prevents axonal regeneration after spinal cord injury (SCI). However, the mechanism by which PDGFRβ+ pericytes migrate to the injury core is unclear. Here, we investigated the effect and mechanism of macrophages polarization on PDGFRβ+ pericytes migration after SCI. Macrophages were closely related to the spatiotemporal distribution of PDGFRβ+ pericytes in the injury core at 3, 7, and 14 days postinjury (dpi). Macrophages appeared M2 polarization at 3 and 7 dpi while M1 polarization at 14 dpi. The expression of platelet derived growth factor B (PDGFB) was significantly increased after SCI and after macrophages M2 polarization. The promoting effect of exogenous PDGFB and M2 macrophages conditioned medium on PDGFRβ+ pericytes migration could be blocked by SU16f, a PDGFRβ specific inhibitor. These findings indicate that M2 macrophages can secrete PDGFB acting on PDGFRβ to promote PDGFRβ+ pericytes migration, which can be blocked by a PDGFRβ specific inhibitor SU16f. The PDGFB/PDGFRβ pathway is a promising new target for the treatment of SCI.
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Affiliation(s)
- Ziyu Li
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
| | - Meige Zheng
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
| | - Shuisheng Yu
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
| | - Fei Yao
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
| | - Yang Luo
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
| | - Yanchang Liu
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
| | - Dasheng Tian
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
| | - Li Cheng
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
| | - Juehua Jing
- Department of Orthopaedics, The Second Hospital of Anhui Medical University, Hefei, China
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17
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Tsata V, Möllmert S, Schweitzer C, Kolb J, Möckel C, Böhm B, Rosso G, Lange C, Lesche M, Hammer J, Kesavan G, Beis D, Guck J, Brand M, Wehner D. A switch in pdgfrb + cell-derived ECM composition prevents inhibitory scarring and promotes axon regeneration in the zebrafish spinal cord. Dev Cell 2021; 56:509-524.e9. [PMID: 33412105 DOI: 10.1016/j.devcel.2020.12.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 10/12/2020] [Accepted: 12/07/2020] [Indexed: 12/13/2022]
Abstract
In mammals, perivascular cell-derived scarring after spinal cord injury impedes axonal regrowth. In contrast, the extracellular matrix (ECM) in the spinal lesion site of zebrafish is permissive and required for axon regeneration. However, the cellular mechanisms underlying this interspecies difference have not been investigated. Here, we show that an injury to the zebrafish spinal cord triggers recruitment of pdgfrb+ myoseptal and perivascular cells in a PDGFR signaling-dependent manner. Interference with pdgfrb+ cell recruitment or depletion of pdgfrb+ cells inhibits axonal regrowth and recovery of locomotor function. Transcriptional profiling and functional experiments reveal that pdgfrb+ cells upregulate expression of axon growth-promoting ECM genes (cthrc1a and col12a1a/b) and concomitantly reduce synthesis of matrix molecules that are detrimental to regeneration (lum and mfap2). Our data demonstrate that a switch in ECM composition is critical for axon regeneration after spinal cord injury and identify the cellular source and components of the growth-promoting lesion ECM.
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Affiliation(s)
- Vasiliki Tsata
- Center for Regenerative Therapies TU Dresden, Technische Universität Dresden, 01307 Dresden, Germany; Developmental Biology, Clinical, Experimental Surgery and Translational Research Center, Biomedical Research Foundation Academy of Athens, 11527 Athens, Greece
| | - Stephanie Möllmert
- Max Planck Institute for the Science of Light, 91058 Erlangen, Germany; Max-Planck-Zentrum für Physik und Medizin, 91058 Erlangen, Germany
| | - Christine Schweitzer
- Max Planck Institute for the Science of Light, 91058 Erlangen, Germany; Max-Planck-Zentrum für Physik und Medizin, 91058 Erlangen, Germany
| | - Julia Kolb
- Max Planck Institute for the Science of Light, 91058 Erlangen, Germany; Max-Planck-Zentrum für Physik und Medizin, 91058 Erlangen, Germany
| | - Conrad Möckel
- Max Planck Institute for the Science of Light, 91058 Erlangen, Germany; Max-Planck-Zentrum für Physik und Medizin, 91058 Erlangen, Germany
| | - Benjamin Böhm
- Max Planck Institute for the Science of Light, 91058 Erlangen, Germany; Max-Planck-Zentrum für Physik und Medizin, 91058 Erlangen, Germany
| | - Gonzalo Rosso
- Max Planck Institute for the Science of Light, 91058 Erlangen, Germany; Max-Planck-Zentrum für Physik und Medizin, 91058 Erlangen, Germany; Institute of Physiology II, University of Münster, 48149 Münster, Germany
| | - Christian Lange
- Center for Regenerative Therapies TU Dresden, Technische Universität Dresden, 01307 Dresden, Germany
| | - Mathias Lesche
- DRESDEN-concept Genome Center c/o Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, 01307 Dresden, Germany
| | - Juliane Hammer
- Center for Regenerative Therapies TU Dresden, Technische Universität Dresden, 01307 Dresden, Germany
| | - Gokul Kesavan
- Center for Regenerative Therapies TU Dresden, Technische Universität Dresden, 01307 Dresden, Germany
| | - Dimitris Beis
- Developmental Biology, Clinical, Experimental Surgery and Translational Research Center, Biomedical Research Foundation Academy of Athens, 11527 Athens, Greece
| | - Jochen Guck
- Max Planck Institute for the Science of Light, 91058 Erlangen, Germany; Max-Planck-Zentrum für Physik und Medizin, 91058 Erlangen, Germany; Biotechnology Center, Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, 01307 Dresden, Germany
| | - Michael Brand
- Center for Regenerative Therapies TU Dresden, Technische Universität Dresden, 01307 Dresden, Germany; Biotechnology Center, Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, 01307 Dresden, Germany
| | - Daniel Wehner
- Center for Regenerative Therapies TU Dresden, Technische Universität Dresden, 01307 Dresden, Germany; Max Planck Institute for the Science of Light, 91058 Erlangen, Germany; Max-Planck-Zentrum für Physik und Medizin, 91058 Erlangen, Germany.
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18
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Heinzel J, Längle G, Oberhauser V, Hausner T, Kolbenschlag J, Prahm C, Grillari J, Hercher D. Use of the CatWalk gait analysis system to assess functional recovery in rodent models of peripheral nerve injury – a systematic review. J Neurosci Methods 2020; 345:108889. [DOI: 10.1016/j.jneumeth.2020.108889] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 07/28/2020] [Accepted: 07/28/2020] [Indexed: 02/07/2023]
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19
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Kim MH, Park SR, Choi BH. Comparative Analysis of the Expression of Chondroitin Sulfate Subtypes and Their Inhibitory Effect on Axonal Growth in the Embryonic, Adult, and Injured Rat Brains. Tissue Eng Regen Med 2020; 18:165-178. [PMID: 32939673 DOI: 10.1007/s13770-020-00295-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 08/01/2020] [Accepted: 08/16/2020] [Indexed: 10/23/2022] Open
Abstract
BACKGROUND Chondroitin sulfate glycosaminoglycans (CS-GAGs) are the primary inhibitory GAGs for neuronal growth after central nervous system (CNS) injury. However, the inhibitory or permissive activity of CS-GAG subtypes is controversial and depends on the physiological needs of CNS tissues. In this study, we investigated the characteristics and effects of CS-GAGs on axonal growth, which was isolated from the brain cortices of normal rat embryo at E18, normal adult rat brain and injured adult rat brain. METHODS Isolated CS-GAGs from embryo, normal adult, and injured adult rat brains were used for analyzing their effect on attachment and axonal growth using modified spot assay with dorsal root ganglion (DRG) explants and cerebellar granule neurons (CGNs). CS-GAGs were separated using high performance liquid chromatography (HPLC), and the subtypes of CS-GAGs were analyzed. RESULTS CS-GAGs of all three groups inhibited CGN attachment and axonal growth of DRGs. However, CS-GAGs of normal adult rat brain exhibited higher inhibitory activity than those of the other groups in both assays. When subtypes of CS-GAGs were analyzed using HPLC, CS-A (4S) was the most abundant in all three groups and found in largest amount in normal adult rat brain. In contrast, unsulfated CS (CS0) and CS-C (6S) were more abundant by 3-4-folds in E18 group than in the two adult groups. CONCLUSION When compared with the normal adult rat brain, injured rat brain showed relatively similar patterns to that of embryonic rat brain at E18 in the expression of CS subtypes and their inhibitory effect on axonal growth. This phenomenon could be due to differential expression of CS-GAGs subtypes causing decrease in the amount of CS-A and mature-type CS proteoglycan core proteins.
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Affiliation(s)
- Moon Hang Kim
- Biomedical Research Institute, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea
| | - So Ra Park
- Department of Physiology, Inha University College of Medicine, 100 Inha-ro, Michuhol-gu, Incheon, 22212, Republic of Korea
| | - Byung Hyune Choi
- Department of Biomedical Sciences, Inha University College of Medicine, 100 Inha-ro, Michuhol-gu, Incheon, 22212, Republic of Korea.
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20
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Nakhjiri E, Vafaee MS, Hojjati SMM, Shahabi P, Shahpasand K. Tau Pathology Triggered by Spinal Cord Injury Can Play a Critical Role in the Neurotrauma Development. Mol Neurobiol 2020; 57:4845-4855. [PMID: 32808121 DOI: 10.1007/s12035-020-02061-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 08/07/2020] [Indexed: 02/08/2023]
Abstract
Traumatic spinal cord injury (SCI) can result in substantial neurological impairment along with significant emotional and psychological distress. It is clear that there is profound neurodegeneration upon SCI, gradually spread to other spinal cord regions and brain areas. Despite extensive considerations, it remains uncertain how pathogenicity diffuses in the cord. It has been reported that tau protein abnormal hyperphosphorylation plays a central role in neurodegeneration triggered by traumatic brain injury (TBI). Tau is a microtubule-associated protein, heavily implicated in neurodegenerative diseases. Importantly, tau pathology spreads in a traumatic brain in a timely manner. In particular, we have recently demonstrated that phosphorylated tau at Thr231 exists in two distinct cis and trans conformations, in which that cis P-tau is extremely neurotoxic, has a prion nature, and spreads to various brain areas and cerebrospinal fluid (CSF) upon trauma. On the other hand, tau pathology, in particular hyperphosphorylation at Thr231, has been observed upon SCI. Taken these together, we conclude that cis pT231-tau may accumulate and spread in the spinal cord as well as CSF and diffuse tau pathology in the central nervous system (CNS). Moreover, antibody against cis P-tau can target intracellular cis P-tau and protect pathology spreading. Thus, considering cis P-tau as a driver of tau pathology and neurodegeneration upon SCI would open new windows toward understanding the disease development and early biomarkers. Furthermore, it would help us develop effective therapies for SCI patients.
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Affiliation(s)
- Elnaz Nakhjiri
- Neurosciences Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Manuchehr S Vafaee
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark
| | | | - Parviz Shahabi
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Koorosh Shahpasand
- Department of Brain and Cognitive Sciences, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran.
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21
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Danilov CA, Gu Y, Punj V, Wu Z, Steward O, Schönthal AH, Tahara SM, Hofman FM, Chen TC. Intravenous delivery of microRNA-133b along with Argonaute-2 enhances spinal cord recovery following cervical contusion in mice. Spine J 2020; 20:1138-1151. [PMID: 32145360 DOI: 10.1016/j.spinee.2020.02.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 02/26/2020] [Accepted: 02/26/2020] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Acute spinal cord injury (SCI) is a devastating condition for which spine decompression and stabilization of injury remains the only therapy available in the clinical setup. However, fibrous scar formation during the healing process significantly impairs full recovery. MicroRNAs (miRs) are small noncoding RNAs that regulate gene expression by binding to target mRNA(s) and initiating translational repression or mRNA degradation. It has been reported that microRNA-133b (miR133b) is highly expressed in regenerating neurons following a SCI in zebrafish, and lentiviral delivery of miR133b at the time of SCI in mice resulted in improved functional recovery. PURPOSE The aim of this study was to investigate whether intravenous delivery of miR133b enhances spinal cord recovery when administered 24 hours following a cervical contusion injury in mice. STUDY DESIGN This is an experimental animal study of acute SCI, investigating the effect of miR133b on spinal cord recovery by targeting scar lesion formation. The approach involved setting an acute SCI in mice, which was followed 24 hours later by intravenous co-delivery of miR133b and Argonaute 2 (Ago2), a protein involved in miRNA stabilization. Readouts of the impact of this intervention included analysis of RNA and protein expression at the lesion site, in particular with regard to markers of scar tissue formation, and determination of motor function recovery by the grip strength meter task. METHODS C57BL6 female mice between 6 and 8 weeks of age were tested. The injury model employed was a unilateral moderate contusion at the cervical fifth level. Twenty-four hours following the injury, the authors co-delivered miR133b, or scrambled miRNA as negative control, along with Ago2 for 3 consecutive days, one dose per day via tail-vein injection. They first investigated the level of miR133b in the spinal cord and in spinal cord lesion after a single dose of injection. Next, they determined the efficacy of miR133b and/or Ago2 delivery in regulating gene and protein expression at the lesion site. Finally, they established the role of miR133b and/or Ago2 in enhancing forelimb gripping recovery as assessed by the grip strength meter task for 8 weeks post-SCI. RESULTS Intravenous delivery of miR133b and/or Ago2 targeted the microenvironment at the lesion site and prevented the increased expression of certain extracellular matrix proteins (ECM), in particular collagen type 1 alpha 1 and tenascin N, which are known to have a key role in scar formation. It also reduced microglia and/or macrophage recruitment to the lesion site. Functional recovery in mice treated with miR133b and/or Ago2 started around 2 weeks postinjury and continued to improve over time, whereas mice in the control group displayed significantly poorer recovery. CONCLUSIONS Our data indicate therapeutic activity of intravenous miR133b and/or Ago2 treatment, possibly via decreasing ECM protein expression and macrophage recruitment at the lesion site, thereby minimizing detrimental fibrous scar formation. CLINICAL SIGNIFICANCE There is an urgent medical need for better treatments of SCIs. Based on our findings in a preclinical model, the miR133b and/or Ago2 system specifically targets fibrous scar formation, a barrier in neuronal regrowth, by remodeling ECM molecules at the injury site. Prevention of scar formation is critical to improved outcomes of treatment. Of note, delivery of miR133b and/or Ago2 was initiated 24 hours after traumatic impact, thus indicating a fairly long window of opportunity providing more time and flexibility for therapeutic intervention. Intravenous miR133b may become a beneficial therapeutic strategy to treat patients with acute SCI.
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Affiliation(s)
- Camelia A Danilov
- Department of Neurological Surgery, University of Southern California, 2011 Zonal Ave, HMR 414, Los Angeles, CA 90033, USA
| | - Yifei Gu
- Department of Spine Surgery, Changzheng Hospital, Second Military Medical University, 415 Fengyang Rd, Shanghai, China
| | - Vasu Punj
- Department of Medicine, University of Southern California, Health Sciences Campus, NRT G511, Los Angeles, CA 90033, USA
| | - Zhourui Wu
- Division of Spine, Department of Orthopedics, Tongji Hospital affiliated to Tongji University School of Medicine, Shanghai 200065, China; Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration, Ministry of Education of the People's Republic of China, Shanghai 200072, China
| | - Oswald Steward
- Department of Anatomy and Neurobiology, University of California, Irvine, 1105 GNRF, Irvine, CA 92697, USA
| | - Axel H Schönthal
- Department of Molecular Microbiology and Immunology, University of Southern California, 2011 Zonal Ave, HMR 405A, Los Angeles, CA 90033, USA
| | - Stanley M Tahara
- Department of Molecular Microbiology and Immunology, University of Southern California, 2011 Zonal Ave, HMR 510A, Los Angeles, CA 90033, USA
| | - Florence M Hofman
- Department of Pathology, University of Southern California, 2011 Zonal Ave, HMR 315, Los Angeles, CA 90033, USA
| | - Thomas C Chen
- Department of Neurological Surgery, University of Southern California, 1520 San Pablo St, Los Angeles, CA 90089, USA.
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Inhibition of MALT1 paracaspase activity improves lesion recovery following spinal cord injury. Sci Bull (Beijing) 2019; 64:1179-1194. [PMID: 36659689 DOI: 10.1016/j.scib.2019.04.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 03/13/2019] [Accepted: 03/26/2019] [Indexed: 01/21/2023]
Abstract
Spinal cord injury (SCI) is a devastating traumatic injury that causes persistent, severe motor and sensory dysfunction. Immune responses are involved in functional recovery after SCI. Mucosa-associated lymphoid tissue lymphoma translocation 1 (MALT1) has been shown to regulate the survival and differentiation of immune cells and to play a critical role in many diseases, but its function in lesion recovery after SCI remains unclear. In this paper, we generated KI (knock in) mice with a point mutation (C472G) in the active center of MALT1 and found that the KI mice exhibited improved functional recovery after SCI. Fewer macrophages were recruited to the injury site in KI mice and these macrophages differentiated into anti-inflammatory macrophages. Moreover, macrophages from KI mice exhibited reduced phosphorylation of p65, which in turn resulted in decreased SOCS3 expression and increased pSTAT6 levels. Similar results were obtained upon inhibition of MALT1 paracaspase with the small molecule inhibitor "MI-2" or the more specific inhibitor "MLT-827". In patients with SCI, peripheral blood mononuclear cells (PBMC) displayed increased MALT1 paracaspase. Human macrophages showed reduced pro-inflammatory and increased anti-inflammatory characteristics following the inhibition of MALT1 paracaspase. These findings suggest that inhibition of MALT1 paracaspase activity in the clinic may improve lesion recovery in subjects with SCI.
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Bradbury EJ, Burnside ER. Moving beyond the glial scar for spinal cord repair. Nat Commun 2019; 10:3879. [PMID: 31462640 PMCID: PMC6713740 DOI: 10.1038/s41467-019-11707-7] [Citation(s) in RCA: 360] [Impact Index Per Article: 72.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 07/25/2019] [Indexed: 02/08/2023] Open
Abstract
Traumatic spinal cord injury results in severe and irreversible loss of function. The injury triggers a complex cascade of inflammatory and pathological processes, culminating in formation of a scar. While traditionally referred to as a glial scar, the spinal injury scar in fact comprises multiple cellular and extracellular components. This multidimensional nature should be considered when aiming to understand the role of scarring in limiting tissue repair and recovery. In this Review we discuss recent advances in understanding the composition and phenotypic characteristics of the spinal injury scar, the oversimplification of defining the scar in binary terms as good or bad, and the development of therapeutic approaches to target scar components to enable improved functional outcome after spinal cord injury.
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Affiliation(s)
- Elizabeth J Bradbury
- King's College London, Regeneration Group, The Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology & Neuroscience (IoPPN), Guy's Campus, London Bridge, London, SE1 1UL, UK.
| | - Emily R Burnside
- King's College London, Regeneration Group, The Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology & Neuroscience (IoPPN), Guy's Campus, London Bridge, London, SE1 1UL, UK
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24
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Mouse mast cell protease 4 suppresses scar formation after traumatic spinal cord injury. Sci Rep 2019; 9:3715. [PMID: 30842526 PMCID: PMC6403346 DOI: 10.1038/s41598-019-39551-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 01/14/2019] [Indexed: 12/15/2022] Open
Abstract
Spinal cord injury (SCI) triggers the formation of a glial and fibrotic scar, which creates a major barrier for neuroregenerative processes. Previous findings indicate that mast cells (MCs) protect the spinal cord after mechanical damage by suppressing detrimental inflammatory processes via mouse mast cell protease 4 (mMCP4), a MC-specific chymase. In addition to these immunomodulatory properties, mMCP4 also plays an important role in tissue remodeling and extracellular matrix degradation. Therefore, we have investigated the effects of mMCP4 on the scarring response after SCI. We demonstrate that the decrease in locomotor performance in mMCP4-/- mice is correlated with excessive scar formation at the lesion. The expression of axon-growth inhibitory chondroitin sulfate proteoglycans was dramatically increased in the perilesional area in mMCP4-/- mice compared to wild type mice. Moreover, the fibronectin-, laminin-, and collagen IV-positive scar was significantly enlarged in mMCP4-/- mice at the lesion center. A degradation assay revealed that mMCP4 directly cleaves collagen IV in vitro. On the gene expression level, neurocan and GFAP were significantly higher in the mMCP4-/- group at day 2 and day 28 after injury respectively. In contrast, the expression of fibronectin and collagen IV was reduced in mMCP4-/- mice compared to WT mice at day 7 after SCI. In conclusion, our data show that mMCP4 modulates scar development after SCI by altering the gene and protein expression patterns of key scar factors in vivo. Therefore, we suggest a new mechanism via which endogenous mMCP4 can improve recovery after SCI.
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25
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García E, Rodríguez-Barrera R, Buzoianu-Anguiano V, Flores-Romero A, Malagón-Axotla E, Guerrero-Godinez M, De la Cruz-Castillo E, Castillo-Carvajal L, Rivas-Gonzalez M, Santiago-Tovar P, Morales I, Borlongan C, Ibarra A. Use of a combination strategy to improve neuroprotection and neuroregeneration in a rat model of acute spinal cord injury. Neural Regen Res 2019; 14:1060-1068. [PMID: 30762019 PMCID: PMC6404491 DOI: 10.4103/1673-5374.250627] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Spinal cord injury is a very common pathological event that has devastating functional consequences in patients. In recent years, several research groups are trying to find an effective therapy that could be applied in clinical practice. In this study, we analyzed the combination of different strategies as a potential therapy for spinal cord injury. Immunization with neural derived peptides (INDP), inhibition of glial scar formation (dipyridyl: DPY), as well as the use of biocompatible matrix (fibrin glue: FG) impregnated with bone marrow mesenchymal stem cells (MSCs) were combined and then its beneficial effects were evaluated in the induction of neuroprotection and neuroregeneration after acute SCI. Sprague-Dawley female rats were subjected to a moderate spinal cord injury and then randomly allocated into five groups: 1) phosphate buffered saline; 2) DPY; 3) INDP + DPY; 4) DPY+ FG; 5) INDP + DPY + FG + MSCs. In all rats, intervention was performed 72 hours after spinal cord injury. Locomotor and sensibility recovery was assessed in all rats. At 60 days after treatment, histological examinations of the spinal cord (hematoxylin-eosin and Bielschowsky staining) were performed. Our results showed that the combination therapy (DPY+ INDP + FG + MSCs) was the best strategy to promote motor and sensibility recovery. In addition, significant increases in tissue preservation and axonal density were observed in the combination therapy group. Findings from this study suggest that the combination theapy (DPY+ INDP + FG + MSCs) exhibits potential effects on the protection and regeneration of neural tissue after acute spinal cord injury. All procedures were approved by the Animal Bioethics and Welfare Committee (approval No. 178544; CSNBTBIBAJ 090812960) on August 15, 2016.
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Affiliation(s)
- Elisa García
- Centro de Investigación en Ciencias de la Salud (CICSA), Facultad de Ciencias de la Salud, Universidad Anáhuac México Campus Norte, Huixquilucan, Edo. de México, México; Centro de Investigación del Proyecto CAMINA A.C.; Ciudad de México, México
| | - Roxana Rodríguez-Barrera
- Centro de Investigación en Ciencias de la Salud (CICSA), Facultad de Ciencias de la Salud, Universidad Anáhuac México Campus Norte, Huixquilucan, Edo. de México, México; Centro de Investigación del Proyecto CAMINA A.C.; Ciudad de México, México
| | - Vinnitsa Buzoianu-Anguiano
- Unidad de Investigación Médica en Enfermedades Neurologicas, Hospital Especialidades CMN Siglo XXI, Ciudad de México, Mexico
| | - Adrian Flores-Romero
- Centro de Investigación en Ciencias de la Salud (CICSA), Facultad de Ciencias de la Salud, Universidad Anáhuac México Campus Norte, Huixquilucan, Edo. de México, México; Centro de Investigación del Proyecto CAMINA A.C.; Ciudad de México, México
| | - Emanuel Malagón-Axotla
- Centro de Investigación en Ciencias de la Salud (CICSA), Facultad de Ciencias de la Salud, Universidad Anáhuac México Campus Norte, Huixquilucan, Edo. de México, México
| | - Marco Guerrero-Godinez
- Unidad de Rehabilitación Osteoarticular. Instituto Nacional de Rehabilitación. Luis Guillermo Ibarra Ibarra, Ciudad de México, Mexico
| | - Estefanía De la Cruz-Castillo
- Centro de Investigación en Ciencias de la Salud (CICSA), Facultad de Ciencias de la Salud, Universidad Anáhuac México Campus Norte, Huixquilucan, Edo. de México, México
| | - Laura Castillo-Carvajal
- Centro de Investigación en Ciencias de la Salud (CICSA), Facultad de Ciencias de la Salud, Universidad Anáhuac México Campus Norte, Huixquilucan, Edo. de México, México
| | - Monserrat Rivas-Gonzalez
- Centro de Investigación en Ciencias de la Salud (CICSA), Facultad de Ciencias de la Salud, Universidad Anáhuac México Campus Norte, Huixquilucan, Edo. de México, México
| | - Paola Santiago-Tovar
- Centro de Investigación en Ciencias de la Salud (CICSA), Facultad de Ciencias de la Salud, Universidad Anáhuac México Campus Norte, Huixquilucan, Edo. de México, México
| | - Ivis Morales
- Centro de Investigación en Ciencias de la Salud (CICSA), Facultad de Ciencias de la Salud, Universidad Anáhuac México Campus Norte, Huixquilucan, Edo. de México, México
| | - Cesar Borlongan
- Center of Excellence for Aging and Brain Repair, Department of Neurosurgery and Brain Repair, University of South Florida Morsani College of Medicine, Tampa, FL, USA
| | - Antonio Ibarra
- Centro de Investigación en Ciencias de la Salud (CICSA), Facultad de Ciencias de la Salud, Universidad Anáhuac México Campus Norte, Huixquilucan, Edo. de México, México; Centro de Investigación del Proyecto CAMINA A.C.; Ciudad de México, México
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Estrada V, Krebbers J, Voss C, Brazda N, Blazyca H, Illgen J, Seide K, Jürgens C, Müller J, Martini R, Trieu HK, Müller HW. Low-pressure micro-mechanical re-adaptation device sustainably and effectively improves locomotor recovery from complete spinal cord injury. Commun Biol 2018; 1:205. [PMID: 30511019 PMCID: PMC6255786 DOI: 10.1038/s42003-018-0210-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 10/31/2018] [Indexed: 12/16/2022] Open
Abstract
Traumatic spinal cord injuries result in impairment or even complete loss of motor, sensory and autonomic functions. Recovery after complete spinal cord injury is very limited even in animal models receiving elaborate combinatorial treatments. Recently, we described an implantable microsystem (microconnector) for low-pressure re-adaption of severed spinal stumps in rat. Here we investigate the long-term structural and functional outcome following microconnector implantation after complete spinal cord transection. Re-adaptation of spinal stumps supports formation of a tissue bridge, glial and vascular cell invasion, motor axon regeneration and myelination, resulting in partial recovery of motor-evoked potentials and a thus far unmet improvement of locomotor behaviour. The recovery lasts for at least 5 months. Despite a late partial decline, motor recovery remains significantly superior to controls. Our findings demonstrate that microsystem technology can foster long-lasting functional improvement after complete spinal injury, providing a new and effective tool for combinatorial therapies.
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Affiliation(s)
- Veronica Estrada
- 1Molecular Neurobiology Laboratory, Department of Neurology, Heinrich-Heine-University Medical Centre Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Julia Krebbers
- 1Molecular Neurobiology Laboratory, Department of Neurology, Heinrich-Heine-University Medical Centre Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Christian Voss
- 2Institute of Microsystems Technology, Hamburg University of Technology, Eißendorfer Str. 42, 21073 Hamburg, Germany.,BG Trauma Centre Hamburg, Bergedorfer Str. 10, 21033 Hamburg, Germany
| | - Nicole Brazda
- 1Molecular Neurobiology Laboratory, Department of Neurology, Heinrich-Heine-University Medical Centre Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Heinrich Blazyca
- 4Developmental Neurobiology, Department of Neurology, University Hospital Würzburg, Josef-Schneider-Str. 11, 97080 Würzburg, Germany
| | - Jennifer Illgen
- 1Molecular Neurobiology Laboratory, Department of Neurology, Heinrich-Heine-University Medical Centre Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Klaus Seide
- BG Trauma Centre Hamburg, Bergedorfer Str. 10, 21033 Hamburg, Germany
| | - Christian Jürgens
- BG Trauma Centre Hamburg, Bergedorfer Str. 10, 21033 Hamburg, Germany
| | - Jörg Müller
- 2Institute of Microsystems Technology, Hamburg University of Technology, Eißendorfer Str. 42, 21073 Hamburg, Germany
| | - Rudolf Martini
- 4Developmental Neurobiology, Department of Neurology, University Hospital Würzburg, Josef-Schneider-Str. 11, 97080 Würzburg, Germany
| | - Hoc Khiem Trieu
- 2Institute of Microsystems Technology, Hamburg University of Technology, Eißendorfer Str. 42, 21073 Hamburg, Germany
| | - Hans Werner Müller
- 1Molecular Neurobiology Laboratory, Department of Neurology, Heinrich-Heine-University Medical Centre Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany.,CNR (Center for Neuronal Regeneration), Merowinger Platz 1a, 40225 Düsseldorf, Germany.,6Biomedical Research Center, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
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Goodus MT, Sauerbeck AD, Popovich PG, Bruno RS, McTigue DM. Dietary Green Tea Extract Prior to Spinal Cord Injury Prevents Hepatic Iron Overload but Does Not Improve Chronic Hepatic and Spinal Cord Pathology in Rats. J Neurotrauma 2018; 35:2872-2882. [PMID: 30084733 DOI: 10.1089/neu.2018.5771] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Spinal cord injury (SCI) disrupts autonomic regulation of visceral organs. As a result, a leading cause of mortality in the SCI population is metabolic dysfunction, and an organ central to metabolic control is the liver. Our recent work showed that rodent SCI promotes Kupffer cell (hepatic macrophage) activation, pro-inflammatory cytokine expression, and liver steatosis. These are symptoms of nonalcoholic steatohepatitis (NASH), the hepatic manifestation of metabolic syndrome, and these pre-clinical data replicate aspects of post-SCI human metabolic dysfunction. Because metabolic profile is highly dependent on lifestyle, including diet, it is likely that lifestyle choices prior to injury influence metabolic and hepatic outcomes after SCI. Therefore, in this study we tested if a diet rich in green tea extract (GTE), a known hepatoprotective agent, that began 3 weeks before SCI and was maintained after injury, reduced indices of liver pathology or metabolic dysfunction. GTE treatment significantly reduced post-SCI hepatic iron accumulation and blunted circulating glucose elevation compared with control-diet rats. However, GTE pre-treatment did not prevent Kupffer cell activation, hepatic lipid accumulation, increased serum alanine transaminase, or circulating non-esterified fatty acids, which were all significantly increased 6 weeks post-injury. Spinal cord pathology also was unchanged by GTE. Thus, dietary GTE prior to and after SCI had only a minor hepatoprotective effect. In general, for optimal health of SCI individuals, it will be important for future studies to evaluate how other lifestyle choices made before or after SCI positively or negatively impact systemic and intraspinal outcomes and the overall metabolic health of SCI individuals.
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Affiliation(s)
- Matthew T Goodus
- 1 The Center for Brain and Spinal Cord Repair, College of Education and Human Ecology, The Ohio State University, Columbus, Ohio.,2 Department of Neuroscience, College of Education and Human Ecology, The Ohio State University, Columbus, Ohio.,3 Belford Center for Spinal Cord Injury, Wexner Medical Center, College of Education and Human Ecology, The Ohio State University, Columbus, Ohio
| | - Andrew D Sauerbeck
- 1 The Center for Brain and Spinal Cord Repair, College of Education and Human Ecology, The Ohio State University, Columbus, Ohio.,2 Department of Neuroscience, College of Education and Human Ecology, The Ohio State University, Columbus, Ohio
| | - Phillip G Popovich
- 1 The Center for Brain and Spinal Cord Repair, College of Education and Human Ecology, The Ohio State University, Columbus, Ohio.,2 Department of Neuroscience, College of Education and Human Ecology, The Ohio State University, Columbus, Ohio.,3 Belford Center for Spinal Cord Injury, Wexner Medical Center, College of Education and Human Ecology, The Ohio State University, Columbus, Ohio
| | - Richard S Bruno
- 4 Human Nutrition Program, College of Education and Human Ecology, The Ohio State University, Columbus, Ohio
| | - Dana M McTigue
- 1 The Center for Brain and Spinal Cord Repair, College of Education and Human Ecology, The Ohio State University, Columbus, Ohio.,2 Department of Neuroscience, College of Education and Human Ecology, The Ohio State University, Columbus, Ohio.,3 Belford Center for Spinal Cord Injury, Wexner Medical Center, College of Education and Human Ecology, The Ohio State University, Columbus, Ohio
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Ruschel J, Bradke F. Systemic administration of epothilone D improves functional recovery of walking after rat spinal cord contusion injury. Exp Neurol 2018; 306:243-249. [PMID: 29223322 DOI: 10.1016/j.expneurol.2017.12.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 10/28/2017] [Accepted: 12/04/2017] [Indexed: 01/31/2023]
Abstract
Central nervous system (CNS) injuries cause permanent impairments of sensorimotor functions as mature neurons fail to regenerate their severed axons. The poor intrinsic growth capacity of adult CNS neurons and the formation of an inhibitory lesion scar are key impediments to axon regeneration. Systemic administration of the microtubule stabilizing agent epothilone B promotes axon regeneration and recovery of motor function by activating the intrinsic axonal growth machinery and by reducing the inhibitory fibrotic lesion scar. Thus, epothilones hold clinical promise as potential therapeutics for spinal cord injury. Here we tested the efficacy of epothilone D, an epothilone B analog with a superior safety profile. By using liquid chromatography and mass spectrometry (LC/MS), we found adequate CNS penetration and distribution of epothilone D after systemic administration, confirming the suitability of the drug for non-invasive CNS treatment. Systemic administration of epothilone D reduced inhibitory fibrotic scarring, promoted regrowth of injured raphespinal fibers and improved walking function after mid-thoracic spinal cord contusion injury in adult rats. These results confirm that systemic administration of epothilones is a valuable therapeutic strategy for CNS regeneration and repair after injury and provides a further advance for potential clinical translation.
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Affiliation(s)
- Jörg Ruschel
- German Center for Neurodegenerative Diseases, Sigmund-Freud-Strasse 27, 53127 Bonn, Germany.
| | - Frank Bradke
- German Center for Neurodegenerative Diseases, Sigmund-Freud-Strasse 27, 53127 Bonn, Germany.
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Orr MB, Gensel JC. Spinal Cord Injury Scarring and Inflammation: Therapies Targeting Glial and Inflammatory Responses. Neurotherapeutics 2018; 15:541-553. [PMID: 29717413 PMCID: PMC6095779 DOI: 10.1007/s13311-018-0631-6] [Citation(s) in RCA: 326] [Impact Index Per Article: 54.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Deficits in neuronal function are a hallmark of spinal cord injury (SCI) and therapeutic efforts are often focused on central nervous system (CNS) axon regeneration. However, secondary injury responses by astrocytes, microglia, pericytes, endothelial cells, Schwann cells, fibroblasts, meningeal cells, and other glia not only potentiate SCI damage but also facilitate endogenous repair. Due to their profound impact on the progression of SCI, glial cells and modification of the glial scar are focuses of SCI therapeutic research. Within and around the glial scar, cells deposit extracellular matrix (ECM) proteins that affect axon growth such as chondroitin sulfate proteoglycans (CSPGs), laminin, collagen, and fibronectin. This dense deposition of material, i.e., the fibrotic scar, is another barrier to endogenous repair and is a target of SCI therapies. Infiltrating neutrophils and monocytes are recruited to the injury site through glial chemokine and cytokine release and subsequent upregulation of chemotactic cellular adhesion molecules and selectins on endothelial cells. These peripheral immune cells, along with endogenous microglia, drive a robust inflammatory response to injury with heterogeneous reparative and pathological properties and are targeted for therapeutic modification. Here, we review the role of glial and inflammatory cells after SCI and the therapeutic strategies that aim to replace, dampen, or alter their activity to modulate SCI scarring and inflammation and improve injury outcomes.
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Affiliation(s)
- Michael B Orr
- Spinal Cord and Brain Injury Research Center, Department of Physiology, University of Kentucky College of Medicine, 741 S. Limestone, B463 BBSRB, Lexington, Kentucky, 40536, USA
| | - John C Gensel
- Spinal Cord and Brain Injury Research Center, Department of Physiology, University of Kentucky College of Medicine, 741 S. Limestone, B463 BBSRB, Lexington, Kentucky, 40536, USA.
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GABA promotes survival and axonal regeneration in identifiable descending neurons after spinal cord injury in larval lampreys. Cell Death Dis 2018; 9:663. [PMID: 29950557 PMCID: PMC6021415 DOI: 10.1038/s41419-018-0704-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 04/24/2018] [Accepted: 05/14/2018] [Indexed: 12/25/2022]
Abstract
The poor regenerative capacity of descending neurons is one of the main causes of the lack of recovery after spinal cord injury (SCI). Thus, it is of crucial importance to find ways to promote axonal regeneration. In addition, the prevention of retrograde degeneration leading to the atrophy/death of descending neurons is an obvious prerequisite to activate axonal regeneration. Lampreys show an amazing regenerative capacity after SCI. Recent histological work in lampreys suggested that GABA, which is massively released after a SCI, could promote the survival of descending neurons. Here, we aimed to study if GABA, acting through GABAB receptors, promotes the survival and axonal regeneration of descending neurons of larval sea lampreys after a complete SCI. First, we used in situ hybridization to confirm that identifiable descending neurons of late-stage larvae express the gabab1 subunit of the GABAB receptor. We also observed an acute increase in the expression of this subunit in descending neurons after SCI, which further supported the possible role of GABA and GABAB receptors in promoting the survival and regeneration of these neurons. So, we performed gain and loss of function experiments to confirm this hypothesis. Treatments with GABA and baclofen (GABAB agonist) significantly reduced caspase activation in descending neurons 2 weeks after a complete SCI. Long-term treatments with GABOB (a GABA analogue) and baclofen significantly promoted axonal regeneration of descending neurons after SCI. These data indicate that GABAergic signalling through GABAB receptors promotes the survival and regeneration of descending neurons after SCI. Finally, we used morpholinos against the gabab1 subunit to knockdown the expression of the GABAB receptor in descending neurons. Long-term morpholino treatments caused a significant inhibition of axonal regeneration. This shows that endogenous GABA promotes axonal regeneration after a complete SCI in lampreys by activating GABAB receptors.
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31
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Wang W, Tang S, Li H, Liu R, Su Y, Shen L, Sun M, Ning B. MicroRNA-21a-5p promotes fibrosis in spinal fibroblasts after mechanical trauma. Exp Cell Res 2018; 370:24-30. [PMID: 29883711 DOI: 10.1016/j.yexcr.2018.06.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2018] [Revised: 06/03/2018] [Accepted: 06/04/2018] [Indexed: 02/06/2023]
Abstract
Traumatic spinal cord injury (SCI) causes permanent disability to at least 180,000 people per year worldwide. Early regulation of spinal fibroblast proliferation may inhibit fibrotic scar formation, allowing the creation of a favorable environment for neuronal regeneration and thereby enhancing recovery from traumatic SCIs. In this study, we aimed to identify the role of microRNA-21a-5p (miR-21a-5p) in regulating spinal fibroblasts after mechanical trauma and to investigate the dysregulation of miR-21a-5p in the pathological process of spinal SCI. We investigated the differential expression of microRNAs in primary spinal fibroblasts after mechanical trauma and found that the expression of miR-21a-5p was higher in spinal fibroblasts after scratch damage (SD). In addition, mouse spinal fibroblasts were transfected with miR-21a-5p mimics/inhibitor, and the role of miR-21a-5p in spinal fibrogenic activation was analyzed. These experiments demonstrated that miR-21a-5p overexpression promoted fibrogenic activity in spinal fibroblasts after mechanical trauma, as well as enhancing proliferation and attenuating apoptosis in spinal fibroblasts. Finally, the potential role of miR-21a-5p in regulating the Smad signaling pathway was examined. MiR-21a-5p activated the Smad signaling pathway by enhancing Smad2/3 phosphorylation. These results suggest that miR-21a-5p promotes spinal fibrosis after mechanical trauma. Based on these findings, we propose a close relationship between miR-21a-5p and spinal fibrosis, providing a new potential therapeutic target for SCI.
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Affiliation(s)
- Wenzhao Wang
- Department of Spinal Surgery, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong, China
| | - Shi Tang
- Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Hongfei Li
- Department of Spinal Surgery, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong, China
| | - Ronghan Liu
- Department of Spinal Surgery, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong, China
| | - Yanlin Su
- Department of Spinal Surgery, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong, China
| | - Lin Shen
- Department of Spinal Surgery, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong, China
| | - Mingjie Sun
- Department of Spinal Surgery, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong, China
| | - Bin Ning
- Department of Spinal Surgery, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong, China.
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Sobrido-Cameán D, Barreiro-Iglesias A. Role of Caspase-8 and Fas in Cell Death After Spinal Cord Injury. Front Mol Neurosci 2018; 11:101. [PMID: 29666570 PMCID: PMC5891576 DOI: 10.3389/fnmol.2018.00101] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 03/15/2018] [Indexed: 01/10/2023] Open
Abstract
Spinal cord injury (SCI) causes the death of neurons and glial cells due to the initial mechanical forces (i.e., primary injury) and through a cascade of secondary molecular events (e.g., inflammation or excitotoxicity) that exacerbate cell death. The loss of neurons and glial cells that are not replaced after the injury is one of the main causes of disability after SCI. Evidence accumulated in last decades has shown that the activation of apoptotic mechanisms is one of the factors causing the death of intrinsic spinal cord (SC) cells following SCI. Although this is not as clear for brain descending neurons, some studies have also shown that apoptosis can be activated in the brain following SCI. There are two main apoptotic pathways, the extrinsic and the intrinsic pathways. Activation of caspase-8 is an important step in the initiation of the extrinsic pathway. Studies in rodents have shown that caspase-8 is activated in SC glial cells and neurons and that the Fas receptor plays a key role in its activation following a traumatic SCI. Recent work in the lamprey model of SCI has also shown the retrograde activation of caspase-8 in brain descending neurons following SCI. Here, we review our current knowledge on the role of caspase-8 and the Fas pathway in cell death following SCI. We also provide a perspective for future work on this process, like the importance of studying the possible contribution of Fas/caspase-8 signaling in the degeneration of brain neurons after SCI in mammals.
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Affiliation(s)
- Daniel Sobrido-Cameán
- Department of Functional Biology, CIBUS, Faculty of Biology, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Antón Barreiro-Iglesias
- Department of Functional Biology, CIBUS, Faculty of Biology, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
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Non-functionalized soft alginate hydrogel promotes locomotor recovery after spinal cord injury in a rat hemimyelonectomy model. Acta Neurochir (Wien) 2018; 160:449-457. [PMID: 29230560 DOI: 10.1007/s00701-017-3389-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 10/31/2017] [Indexed: 12/29/2022]
Abstract
BACKGROUND Spinal cord injury (SCI) and the consecutive devastating neurological sequelae have an enormous individual and economic impact. Implantation of functionalized hydrogels is a promising approach, because they can serve as a matrix for the regenerating tissue, carry and release bioactive molecules and various cell types. We already demonstrated that non-functionalized soft alginate hydrogel supported axonal outgrowth and protected neurons against oxidative stress in vitro. Here, we investigated the effects of such soft alginate hydrogels on locomotor recovery in small and large spinal cord lesions. METHOD Hemimyelonectomy of 2 mm or 4 mm length was performed in rats and soft alginate hydrogel was implanted. Functional recovery of the hindlimbs was assessed in the open field [Batto Beattie Bresnahan (BBB) score] and using swimming test [Louisville Swim score (LSS)] for 140 days post injury (DPI). Reference histology was performed. RESULTS Rats that received an alginate implant into 2 mm spinal cord lesions demonstrated significantly improved locomotor recovery compared to controls detectable already at 10 DPI. At 140 DPI, they reached higher LSS and BBB scores in swimming and open field tests, respectively. However, this beneficial effect of alginate was lacking in animals with larger (4 mm) lesions. Histological examination suggested that fibrous scarring in the spinal cord was reduced after alginate implantation in comparison to controls. CONCLUSIONS Implantation of soft alginate hydrogel in small spinal cord lesions improved functional recovery. Possible underlying mechanisms include the mechanical stabilization of the wound, reduction of secondary damage and inhibition of fibrous scarring.
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Proliferating NG2-Cell-Dependent Angiogenesis and Scar Formation Alter Axon Growth and Functional Recovery After Spinal Cord Injury in Mice. J Neurosci 2017; 38:1366-1382. [PMID: 29279310 DOI: 10.1523/jneurosci.3953-16.2017] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 11/18/2017] [Accepted: 12/17/2017] [Indexed: 01/10/2023] Open
Abstract
Spinal cord injury (SCI) induces a centralized fibrotic scar surrounded by a reactive glial scar at the lesion site. The origin of these scars is thought to be perivascular cells entering lesions on ingrowing blood vessels and reactive astrocytes, respectively. However, two NG2-expressing cell populations, pericytes and glia, may also influence scar formation. In the periphery, new blood vessel growth requires proliferating NG2+ pericytes; if this were also true in the CNS, then the fibrotic scar would depend on dividing NG2+ pericytes. NG2+ glial cells (also called oligodendrocyte progenitors or polydendrocytes) also proliferate after SCI and accumulate in large numbers among astrocytes in the glial scar. Their effect there, if any, is unknown. We show that proliferating NG2+ pericytes and glia largely segregate into the fibrotic and glial scars, respectively; therefore, we used a thymidine kinase/ganciclovir paradigm to ablate both dividing NG2+ cell populations to determine whether either scar was altered. Results reveal that loss of proliferating NG2+ pericytes in the lesion prevented intralesion angiogenesis and completely abolished the fibrotic scar. The glial scar was also altered in the absence of acutely dividing NG2+ cells, displaying discontinuous borders and significantly reduced GFAP density. Collectively, these changes enhanced edema, prolonged hemorrhage, and impaired forelimb functional recovery. Interestingly, after halting GCV at 14 d postinjury, scar elements and vessels entered the lesions over the next 7 d, as did large numbers of axons that were not present in controls. Collectively, these data reveal that acutely dividing NG2+ pericytes and glia play fundamental roles in post-SCI tissue remodeling.SIGNIFICANCE STATEMENT Spinal cord injury (SCI) is characterized by formation of astrocytic and fibrotic scars, both of which are necessary for lesion repair. NG2+ cells may influence both scar-forming processes. This study used a novel transgenic mouse paradigm to ablate proliferating NG2+ cells after SCI to better understand their role in repair. For the first time, our data show that dividing NG2+ pericytes are required for post-SCI angiogenesis, which in turn is needed for fibrotic scar formation. Moreover, loss of cycling NG2+ glia and pericytes caused significant multicellular tissue changes, including altered astrocyte responses and impaired functional recovery. This work reveals previously unknown ways in which proliferating NG2+ cells contribute to endogenous repair after SCI.
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Retrograde Activation of the Extrinsic Apoptotic Pathway in Spinal-Projecting Neurons after a Complete Spinal Cord Injury in Lampreys. BIOMED RESEARCH INTERNATIONAL 2017; 2017:5953674. [PMID: 29333445 PMCID: PMC5733621 DOI: 10.1155/2017/5953674] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 10/25/2017] [Indexed: 12/15/2022]
Abstract
Spinal cord injury (SCI) is a devastating condition that leads to permanent disability because injured axons do not regenerate across the trauma zone to reconnect to their targets. A prerequisite for axonal regeneration will be the prevention of retrograde degeneration that could lead to neuronal death. However, the specific molecular mechanisms of axotomy-induced degeneration of spinal-projecting neurons have not been elucidated yet. In lampreys, SCI induces the apoptotic death of identifiable descending neurons that are “bad regenerators/poor survivors” after SCI. Here, we investigated the apoptotic process activated in identifiable descending neurons of lampreys after SCI. For this, we studied caspase activation by using fluorochrome-labeled inhibitors of caspases, the degeneration of spinal-projecting neurons using Fluro-Jade C staining, and the involvement of the intrinsic apoptotic pathway by means of cytochrome c and Vα double immunofluorescence. Our results provide evidence that, after SCI, bad-regenerating spinal cord-projecting neurons slowly degenerate and that the extrinsic pathway of apoptosis is involved in this process. Experiments using the microtubule stabilizer Taxol showed that caspase-8 signaling is retrogradely transported by microtubules from the site of axotomy to the neuronal soma. Preventing the activation of this process could be an important therapeutic approach after SCI in mammals.
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Kim M, Kim KH, Song SU, Yi TG, Yoon SH, Park SR, Choi BH. Transplantation of human bone marrow-derived clonal mesenchymal stem cells reduces fibrotic scar formation in a rat spinal cord injury model. J Tissue Eng Regen Med 2017; 12:e1034-e1045. [PMID: 28112873 DOI: 10.1002/term.2425] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 12/22/2016] [Accepted: 01/19/2017] [Indexed: 12/20/2022]
Abstract
This study aimed to evaluate the therapeutic effect on tissue repair and scar formation of human bone marrow-derived clonal mesenchymal stem cells (hcMSCs) homogeneously isolated by using a subfractionation culturing method, in comparison with the non-clonal MSCs (hMSCs), in a rat spinal cord injury (SCI) model. The SCI was made using a vascular clip at the T9 level. Cells were transplanted into the lesion site 3 days after injury. A functional test was performed over 4 weeks employing a BBB score. Rats were killed for histological analysis at 3 days, 1 week and 4 weeks after injury. The transplantation of hMSCs and hcMSCs significantly reduced lesion size and the fluid-filled cavity at 4 weeks in comparison with the control group injected with phosphate buffered saline (PBS) (p < 0.01). Transplantation of hcMSCs showed more axons reserved than that of hMSCs in the lesion epicentre filled with non-neuronal tissues. In addition, hMSCs and hcMSCs clearly reduced the inflammatory reaction and intraparenchymal hemorrhaging, compared with the PBS group. Interestingly, hcMSCs largely decreased Col IV expression, one of the markers of fibrotic scars. hcMSCs yielded therapeutic effects more than equal to those of hMSCs on the SCI. Both hMSCs and hcMSCs created an increase in axon regeneration and reduced scar formation around the SCI lesion. Copyright © 2017 John Wiley & Sons, Ltd.
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Affiliation(s)
- Moonhang Kim
- Department of Biomedical Sciences, Inha University College of Medicine, Incheon, Republic of Korea
| | - Kil Hwan Kim
- Veterans Medical Research Institute, VHS Medical Center, Seoul, Republic of Korea
| | - Sun U Song
- Translational Research Center, Inha University College of Medicine, Incheon, Republic of Korea.,SCM Lifescience Co., Ltd., Incheon, Republic of Korea
| | - Tac Ghee Yi
- Translational Research Center, Inha University College of Medicine, Incheon, Republic of Korea.,SCM Lifescience Co., Ltd., Incheon, Republic of Korea
| | - Seung Hwan Yoon
- Department of Neurosurgery, Inha University College of Medicine, Incheon, Republic of Korea
| | - So Ra Park
- Department of Physiology, Inha University College of Medicine, Incheon, Republic of Korea
| | - Byung Hyune Choi
- Department of Biomedical Sciences, Inha University College of Medicine, Incheon, Republic of Korea
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Blaško J, Szekiova E, Slovinska L, Kafka J, Cizkova D. Axonal outgrowth stimulation after alginate/mesenchymal stem cell therapy in injured rat spinal cord. Acta Neurobiol Exp (Wars) 2017. [DOI: 10.21307/ane-2017-066] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Sun GD, Chen Y, Zhou ZG, Yang SX, Zhong C, Li ZZ. A progressive compression model of thoracic spinal cord injury in mice: function assessment and pathological changes in spinal cord. Neural Regen Res 2017; 12:1365-1374. [PMID: 28966654 PMCID: PMC5607834 DOI: 10.4103/1673-5374.213693] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Non-traumatic injury accounts for approximately half of clinical spinal cord injury, including chronic spinal cord compression. However, previous rodent spinal cord compression models are mainly designed for rats, few are available for mice. Our aim is to develop a thoracic progressive compression mice model of spinal cord injury. In this study, adult wild-type C57BL/6 mice were divided into two groups: in the surgery group, a screw was inserted at T9 lamina to compress the spinal cord, and the compression was increased by turning it further into the canal (0.2 mm) post-surgery every 2 weeks up to 8 weeks. In the control group, a hole was drilled into the lamina without inserting a screw. The results showed that Basso Mouse Scale scores were lower and gait worsened. In addition, the degree of hindlimb dysfunction in mice was consistent with the degree of spinal cord compression. The number of motor neurons in the anterior horn of the spinal cord was reduced in all groups of mice, whereas astrocytes and microglia were gradually activated and proliferated. In conclusion, this progressive compression of thoracic spinal cord injury in mice is a preferable model for chronic progressive spinal cord compression injury.
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Affiliation(s)
- Guo-Dong Sun
- Department of Orthopedics, First Affiliated Hospital, Jinan University, Guangzhou, Guangdong Province, China
| | - Yan Chen
- Department of Orthopedics, First Affiliated Hospital, Jinan University, Guangzhou, Guangdong Province, China
| | - Zhi-Gang Zhou
- Department of Orthopedics, First Affiliated Hospital, Jinan University, Guangzhou, Guangdong Province, China
| | - Shu-Xian Yang
- Biomedical Translational Research Institute and Guangdong Province Key Laboratory of Molecular Immunology and Antibody Engineering, Jinan University, Guangzhou, Guangdong Province, China
| | - Cheng Zhong
- Department of Traumatology and Plastic Surgery, The Affiliated Jiangmen Traditional Chinese Medicine Hospital of Jinan University, Jiangmen, Guangdong Province, China
| | - Zhi-Zhong Li
- Department of Orthopedics, First Affiliated Hospital, Jinan University, Guangzhou, Guangdong Province, China.,Department of Orthopedics, Heyuan People's Hospital (Heyuan Affiliated Hospital of Jinan University), Heyuan, Guangdong Province, China
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Zhao W, Chai Y, Hou Y, Wang DW, Xing JQ, Yang C, Fang QM. Mechanisms responsible for the inhibitory effects of epothilone B on scar formation after spinal cord injury. Neural Regen Res 2017; 12:478-485. [PMID: 28469665 PMCID: PMC5399728 DOI: 10.4103/1673-5374.202921] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Scar formation after spinal cord injury is regarded as an obstacle to axonal regeneration and functional recovery. Epothilone B provides moderate microtubule stabilization and is mainly used for anti-tumor therapy. It also reduces scar tissue formation and promotes axonal regeneration after spinal cord injury. The aim of the present study was to investigate the effect and mechanism of the microtubule-stabilizing reagent epothilone B in decreasing fibrotic scarring through its action on pericytes after spinal cord injury. A rat model of spinal cord injury was established via dorsal complete transection at the T10 vertebra. The rats received an intraperitoneal injection of epothilone B (0.75 mg/kg) at 1 and 15 days post-injury in the epothilone B group or normal saline in the vehicle group. Neuron-glial antigen 2, platelet-derived growth factor receptor β, and fibronectin protein expression were dramatically lower in the epothilone B group than in the vehicle group, but β-tubulin protein expression was greater. Glial fibrillary acidic protein at the injury site was not affected by epothilone B treatment. The Basso, Beattie, and Bresnahan locomotor scores were significantly higher in the epothilone B group than in the vehicle group. The results of this study demonstrated that epothilone B reduced the number of pericytes, inhibited extracellular matrix formation, and suppressed scar formation after spinal cord injury.
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Affiliation(s)
- Wei Zhao
- Department of Spinal Surgery, Binzhou Medical University Hospital, Binzhou, Shandong Province, China
| | - Yong Chai
- Department of Anatomy, Binzhou Medical University, Yantai, Shandong Province, China
| | - Yun Hou
- Department of Histology and Embryology, Binzhou Medical University, Yantai, Shandong Province, China
| | - Da-Wei Wang
- Department of Spinal Surgery, Binzhou Medical University Hospital, Binzhou, Shandong Province, China
| | - Jian-Qiang Xing
- Department of Spinal Surgery, Binzhou Medical University Hospital, Binzhou, Shandong Province, China
| | - Cheng Yang
- Department of Anatomy, Binzhou Medical University, Yantai, Shandong Province, China
| | - Qing-Min Fang
- Department of Spinal Surgery, Binzhou Medical University Hospital, Binzhou, Shandong Province, China
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40
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Haggerty AE, Marlow MM, Oudega M. Extracellular matrix components as therapeutics for spinal cord injury. Neurosci Lett 2016; 652:50-55. [PMID: 27702629 DOI: 10.1016/j.neulet.2016.09.053] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2016] [Revised: 09/22/2016] [Accepted: 09/28/2016] [Indexed: 01/09/2023]
Abstract
There is no treatment for people with spinal cord injury that leads to significant functional improvements. The extracellular matrix is an intricate, 3-dimensional, structural framework that defines the environment for cells in the central nervous system. The components of extracellular matrix have signaling and regulatory roles in the fate and function of neuronal and non-neuronal cells in the central nervous system. This review discusses the therapeutic potential of extracellular matrix components for spinal cord repair.
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Affiliation(s)
- Agnes E Haggerty
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, USA.
| | - Megan M Marlow
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Martin Oudega
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL, USA; Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, FL, USA
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41
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Combination of grafted Schwann cells and lentiviral-mediated prevention of glial scar formation improve recovery of spinal cord injured rats. J Chem Neuroanat 2016; 76:48-60. [DOI: 10.1016/j.jchemneu.2015.12.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 11/26/2015] [Accepted: 12/25/2015] [Indexed: 01/03/2023]
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Seehusen F, Al-Azreg SA, Raddatz BB, Haist V, Puff C, Spitzbarth I, Ulrich R, Baumgärtner W. Accumulation of Extracellular Matrix in Advanced Lesions of Canine Distemper Demyelinating Encephalitis. PLoS One 2016; 11:e0159752. [PMID: 27441688 PMCID: PMC4956304 DOI: 10.1371/journal.pone.0159752] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 07/07/2016] [Indexed: 11/18/2022] Open
Abstract
In demyelinating diseases, changes in the quality and quantity of the extracellular matrix (ECM) may contribute to demyelination and failure of myelin repair and axonal sprouting, especially in chronic lesions. To characterize changes in the ECM in canine distemper demyelinating leukoencephalitis (DL), histochemical and immunohistochemical investigations of formalin-fixed paraffin-embedded cerebella using azan, picrosirius red and Gomori`s silver stain as well as antibodies directed against aggrecan, type I and IV collagen, fibronectin, laminin and phosphacan showed alterations of the ECM in CDV-infected dogs. A significantly increased amount of aggrecan was detected in early and late white matter lesions. In addition, the positive signal for collagens I and IV as well as fibronectin was significantly increased in late lesions. Conversely, the expression of phosphacan was significantly decreased in early and more pronounced in late lesions compared to controls. Furthermore, a set of genes involved in ECM was extracted from a publically available microarray data set and was analyzed for differential gene expression. Gene expression of ECM molecules, their biosynthesis pathways, and pro-fibrotic factors was mildly up-regulated whereas expression of matrix remodeling enzymes was up-regulated to a relatively higher extent. Summarized, the observed findings indicate that changes in the quality and content of ECM molecules represent important, mainly post-transcriptional features in advanced canine distemper lesions. Considering the insufficiency of morphological regeneration in chronic distemper lesions, the accumulated ECM seems to play a crucial role upon regenerative processes and may explain the relatively small regenerative potential in late stages of this disease.
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Affiliation(s)
- Frauke Seehusen
- Department of Pathology, University of Veterinary Medicine, Hannover, Germany
| | - Seham A. Al-Azreg
- Department of Pathology, University of Veterinary Medicine, Hannover, Germany
| | - Barbara B. Raddatz
- Department of Pathology, University of Veterinary Medicine, Hannover, Germany
| | - Verena Haist
- Department of Pathology, University of Veterinary Medicine, Hannover, Germany
- Boehringer Ingelheim Veterinary Research Center GmbH & Co. KG, Hannover, Germany
| | - Christina Puff
- Department of Pathology, University of Veterinary Medicine, Hannover, Germany
| | - Ingo Spitzbarth
- Department of Pathology, University of Veterinary Medicine, Hannover, Germany
| | - Reiner Ulrich
- Department of Pathology, University of Veterinary Medicine, Hannover, Germany
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald - Insel Riems, Germany
| | - Wolfgang Baumgärtner
- Department of Pathology, University of Veterinary Medicine, Hannover, Germany
- * E-mail:
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43
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Silver J. The glial scar is more than just astrocytes. Exp Neurol 2016; 286:147-149. [PMID: 27328838 DOI: 10.1016/j.expneurol.2016.06.018] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 06/14/2016] [Accepted: 06/17/2016] [Indexed: 01/06/2023]
Affiliation(s)
- Jerry Silver
- Case Western Reserve University, School of Medicine, Department of Neurosciences, Cleveland, OH 44106, USA.
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44
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Vogelaar CF. Extrinsic and intrinsic mechanisms of axon regeneration: the need for spinal cord injury treatment strategies to address both. Neural Regen Res 2016; 11:572-4. [PMID: 27212916 PMCID: PMC4870912 DOI: 10.4103/1673-5374.180740] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
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Vangansewinkel T, Geurts N, Quanten K, Nelissen S, Lemmens S, Geboes L, Dooley D, Vidal PM, Pejler G, Hendrix S. Mast cells promote scar remodeling and functional recovery after spinal cord injury via mouse mast cell protease 6. FASEB J 2016; 30:2040-57. [PMID: 26917739 DOI: 10.1096/fj.201500114r] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 01/28/2016] [Indexed: 12/12/2022]
Abstract
An important barrier for axon regeneration and recovery after traumatic spinal cord injury (SCI) is attributed to the scar that is formed at the lesion site. Here, we investigated the effect of mouse mast cell protease (mMCP) 6, a mast cell (MC)-specific tryptase, on scarring and functional recovery after a spinal cord hemisection injury. Functional recovery was significantly impaired in both MC-deficient and mMCP6-knockout (mMCP6(-/-)) mice after SCI compared with wild-type control mice. This decrease in locomotor performance was associated with an increased lesion size and excessive scarring at the injury site. Axon growth-inhibitory chondroitin sulfate proteoglycans and the extracellular matrix components fibronectin, laminin, and collagen IV were significantly up-regulated in MC-deficient and mMCP6(-/-) mice, with an increase in scar volume between 23 and 32%. A degradation assay revealed that mMCP6 directly cleaves fibronectin and collagen IV in vitro In addition, gene expression levels of the scar components fibronectin, aggrecan, and collagen IV were increased up to 6.8-fold in mMCP6(-/-) mice in the subacute phase after injury. These data indicate that endogenous mMCP6 has scar-suppressing properties after SCI via indirect cleavage of axon growth-inhibitory scar components and alteration of the gene expression profile of these factors.-Vangansewinkel, T., Geurts, N., Quanten, K., Nelissen, S., Lemmens, S., Geboes, L., Dooley, D., Vidal, P. M., Pejler, G., Hendrix, S. Mast cells promote scar remodeling and functional recovery after spinal cord injury via mouse mast cell protease 6.
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Affiliation(s)
- Tim Vangansewinkel
- Department of Morphology, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Nathalie Geurts
- Department of Morphology, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Kirsten Quanten
- Department of Morphology, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Sofie Nelissen
- Department of Morphology, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Stefanie Lemmens
- Department of Morphology, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Lies Geboes
- Department of Morphology, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Dearbhaile Dooley
- Department of Morphology, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Pia M Vidal
- Department of Morphology, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium
| | - Gunnar Pejler
- Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden; and Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Sven Hendrix
- Department of Morphology, Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium;
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46
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Wu J, Stoica BA, Luo T, Sabirzhanov B, Zhao Z, Guanciale K, Nayar SK, Foss CA, Pomper MG, Faden AI. Isolated spinal cord contusion in rats induces chronic brain neuroinflammation, neurodegeneration, and cognitive impairment. Involvement of cell cycle activation. Cell Cycle 2015; 13:2446-58. [PMID: 25483194 DOI: 10.4161/cc.29420] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Cognitive dysfunction has been reported in patients with spinal cord injury (SCI), but it has been questioned whether such changes may reflect concurrent head injury, and the issue has not been addressed mechanistically or in a well-controlled experimental model. Our recent rodent studies examining SCI-induced hyperesthesia revealed neuroinflammatory changes not only in supratentorial pain-regulatory sites, but also in other brain regions, suggesting that additional brain functions may be impacted following SCI. Here we examined effects of isolated thoracic SCI in rats on cognition, brain inflammation, and neurodegeneration. We show for the first time that SCI causes widespread microglial activation in the brain, with increased expression of markers for activated microglia/macrophages, including translocator protein and chemokine ligand 21 (C-C motif). Stereological analysis demonstrated significant neuronal loss in the cortex, thalamus, and hippocampus. SCI caused chronic impairment in spatial, retention, contextual, and fear-related emotional memory-evidenced by poor performance in the Morris water maze, novel objective recognition, and passive avoidance tests. Based on our prior work implicating cell cycle activation (CCA) in chronic neuroinflammation after SCI or traumatic brain injury, we evaluated whether CCA contributed to the observed changes. Increased expression of cell cycle-related genes and proteins was found in hippocampus and cortex after SCI. Posttraumatic brain inflammation, neuronal loss, and cognitive changes were attenuated by systemic post-injury administration of a selective cyclin-dependent kinase inhibitor. These studies demonstrate that chronic brain neurodegeneration occurs after isolated SCI, likely related to sustained microglial activation mediated by cell cycle activation.
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Affiliation(s)
- Junfang Wu
- a Department of Anesthesiology & Center for Shock, Trauma, and Anesthesiology Research (STAR); University of Maryland School of Medicine; Baltimore, MD USA
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47
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Pharmacological Suppression of CNS Scarring by Deferoxamine Reduces Lesion Volume and Increases Regeneration in an In Vitro Model for Astroglial-Fibrotic Scarring and in Rat Spinal Cord Injury In Vivo. PLoS One 2015. [PMID: 26222542 PMCID: PMC4519270 DOI: 10.1371/journal.pone.0134371] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Lesion-induced scarring is a major impediment for regeneration of injured axons in the central nervous system (CNS). The collagen-rich glial-fibrous scar contains numerous axon growth inhibitory factors forming a regeneration-barrier for axons. We demonstrated previously that the combination of the iron chelator 2,2’-bipyridine-5,5’-decarboxylic acid (BPY-DCA) and 8-Br-cyclic AMP (cAMP) inhibits scar formation and collagen deposition, leading to enhanced axon regeneration and partial functional recovery after spinal cord injury. While BPY-DCA is not a clinical drug, the clinically approved iron chelator deferoxamine mesylate (DFO) may be a suitable alternative for anti-scarring treatment (AST). In order to prove the scar-suppressing efficacy of DFO we modified a recently published in vitro model for CNS scarring. The model comprises a co-culture system of cerebral astrocytes and meningeal fibroblasts, which form scar-like clusters when stimulated with transforming growth factor-β (TGF-β). We studied the mechanisms of TGF-β-induced CNS scarring and compared the efficiency of different putative pharmacological scar-reducing treatments, including BPY-DCA, DFO and cAMP as well as combinations thereof. We observed modulation of TGF-β-induced scarring at the level of fibroblast proliferation and contraction as well as specific changes in the expression of extracellular matrix molecules and axon growth inhibitory proteins. The individual and combinatorial pharmacological treatments had distinct effects on the cellular and molecular aspects of in vitro scarring. DFO could be identified as a putative anti-scarring treatment for CNS trauma. We subsequently validated this by local application of DFO to a dorsal hemisection in the rat thoracic spinal cord. DFO treatment led to significant reduction of scarring, slightly increased regeneration of corticospinal tract as well as ascending CGRP-positive axons and moderately improved locomotion. We conclude that the in vitro model for CNS scarring is suitable for efficient pre-screening and identification of putative scar-suppressing agents prior to in vivo application and validation, thus saving costs, time and laboratory animals.
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48
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Fernández-Klett F, Priller J. The fibrotic scar in neurological disorders. Brain Pathol 2015; 24:404-13. [PMID: 24946078 DOI: 10.1111/bpa.12162] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 05/26/2014] [Indexed: 01/18/2023] Open
Abstract
Tissue fibrosis, or scar formation, is a common response to damage in most organs of the body. The central nervous system (CNS) is special in that fibrogenic cells are restricted to vascular and meningeal niches. However, disruption of the blood-brain barrier and inflammation can unleash stromal cells and trigger scar formation. Astroglia segregate from the inflammatory lesion core, and the so-called "glial scar" composed of hypertrophic astrocytes seals off the intact neural tissue from damage. In the lesion core, a second type of "fibrotic scar" develops, which is sensitive to inflammatory mediators. Genetic fate mapping studies suggest that pericytes and perivascular fibroblasts are activated, but other precursor cells may also be involved in generating a transient fibrous extracellular matrix in the CNS. The stromal cells sense inflammation and attract immune cells, which in turn drive myofibroblast transdifferentiation. We believe that the fibrotic scar represents a major barrier to CNS regeneration. Targeting of fibrosis may therefore prove to be a valuable therapeutic strategy for neurological disorders such as stroke, spinal cord injury and multiple sclerosis.
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Affiliation(s)
- Francisco Fernández-Klett
- Department of Neuropsychiatry and Laboratory of Molecular Psychiatry, Charité-Universitätsmedizin Berlin, Berlin, Germany
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49
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Ruschel J, Hellal F, Flynn KC, Dupraz S, Elliott DA, Tedeschi A, Bates M, Sliwinski C, Brook G, Dobrindt K, Peitz M, Brüstle O, Norenberg MD, Blesch A, Weidner N, Bunge MB, Bixby JL, Bradke F. Axonal regeneration. Systemic administration of epothilone B promotes axon regeneration after spinal cord injury. Science 2015; 348:347-52. [PMID: 25765066 DOI: 10.1126/science.aaa2958] [Citation(s) in RCA: 317] [Impact Index Per Article: 35.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 02/25/2015] [Indexed: 12/14/2022]
Abstract
After central nervous system (CNS) injury, inhibitory factors in the lesion scar and poor axon growth potential prevent axon regeneration. Microtubule stabilization reduces scarring and promotes axon growth. However, the cellular mechanisms of this dual effect remain unclear. Here, delayed systemic administration of a blood-brain barrier-permeable microtubule-stabilizing drug, epothilone B (epoB), decreased scarring after rodent spinal cord injury (SCI) by abrogating polarization and directed migration of scar-forming fibroblasts. Conversely, epothilone B reactivated neuronal polarization by inducing concerted microtubule polymerization into the axon tip, which propelled axon growth through an inhibitory environment. Together, these drug-elicited effects promoted axon regeneration and improved motor function after SCI. With recent clinical approval, epothilones hold promise for clinical use after CNS injury.
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Affiliation(s)
- Jörg Ruschel
- Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases, Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
| | - Farida Hellal
- Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases, Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
| | - Kevin C Flynn
- Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases, Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
| | - Sebastian Dupraz
- Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases, Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
| | - David A Elliott
- Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases, Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
| | - Andrea Tedeschi
- Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases, Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
| | - Margaret Bates
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, 1095 Northwest 14th Terrace, Miami, FL33136, USA
| | - Christopher Sliwinski
- Spinal Cord Injury Center, Heidelberg University Hospital, Schlierbacher Landstr. 200A, 69118 Heidelberg, Germany
| | - Gary Brook
- Institute for Neuropathology, RWTH Aachen University, Steinbergweg 20, 52074, Aachen, Germany. Jülich-Aachen Research Alliance-Translational Brain Medicine
| | - Kristina Dobrindt
- Institute of Reconstructive Neurobiology, Life&Brain Center, University of Bonn and Hertie Foundation, Sigmund-Freud-Strasse 25, 53127 Bonn, Germany
| | - Michael Peitz
- Institute of Reconstructive Neurobiology, Life&Brain Center, University of Bonn and Hertie Foundation, Sigmund-Freud-Strasse 25, 53127 Bonn, Germany
| | - Oliver Brüstle
- Institute of Reconstructive Neurobiology, Life&Brain Center, University of Bonn and Hertie Foundation, Sigmund-Freud-Strasse 25, 53127 Bonn, Germany
| | - Michael D Norenberg
- Departments of Pathology, Biochemistry and Molecular Biology, University of Miami School of Medicine, Miami, FL 33101, USA
| | - Armin Blesch
- Spinal Cord Injury Center, Heidelberg University Hospital, Schlierbacher Landstr. 200A, 69118 Heidelberg, Germany
| | - Norbert Weidner
- Spinal Cord Injury Center, Heidelberg University Hospital, Schlierbacher Landstr. 200A, 69118 Heidelberg, Germany
| | - Mary Bartlett Bunge
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, 1095 Northwest 14th Terrace, Miami, FL33136, USA
| | - John L Bixby
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, 1095 Northwest 14th Terrace, Miami, FL33136, USA
| | - Frank Bradke
- Axonal Growth and Regeneration, German Center for Neurodegenerative Diseases, Ludwig-Erhard-Allee 2, 53175 Bonn, Germany.
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50
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Barreiro-Iglesias A, Shifman MI. Detection of activated caspase-8 in injured spinal axons by using fluorochrome-labeled inhibitors of caspases (FLICA). Methods Mol Biol 2015; 1254:329-39. [PMID: 25431075 DOI: 10.1007/978-1-4939-2152-2_23] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Here, we present a detailed protocol for the detection of activated caspase-8 in axotomized axons of the whole-mounted lamprey spinal cord. This method is based on the use of fluorochrome -labeled inhibitors of caspases (FLICA) in ex vivo tissue. We offer a very convenient vertebrate model to study the retrograde degeneration of descending pathways after spinal cord injury.
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Affiliation(s)
- Antón Barreiro-Iglesias
- Centre for Neuroregeneration, School of Biomedical Sciences, University of Edinburgh, 49 Little France Crescent, Edinburgh, EH16 4SB, UK,
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