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Olaya AMS, Almeida FM, Martinez AMB, Marques SA. Treatment of spinal cord injury with biomaterials and stem cell therapy in non-human primates and humans. Neural Regen Res 2025; 20:343-353. [PMID: 38819038 DOI: 10.4103/nrr.nrr-d-23-01752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 03/27/2024] [Indexed: 06/01/2024] Open
Abstract
Spinal cord injury results in the loss of sensory, motor, and autonomic functions, which almost always produces permanent physical disability. Thus, in the search for more effective treatments than those already applied for years, which are not entirely efficient, researches have been able to demonstrate the potential of biological strategies using biomaterials to tissue manufacturing through bioengineering and stem cell therapy as a neuroregenerative approach, seeking to promote neuronal recovery after spinal cord injury. Each of these strategies has been developed and meticulously evaluated in several animal models with the aim of analyzing the potential of interventions for neuronal repair and, consequently, boosting functional recovery. Although the majority of experimental research has been conducted in rodents, there is increasing recognition of the importance, and need, of evaluating the safety and efficacy of these interventions in non-human primates before moving to clinical trials involving therapies potentially promising in humans. This article is a literature review from databases (PubMed, Science Direct, Elsevier, Scielo, Redalyc, Cochrane, and NCBI) from 10 years ago to date, using keywords (spinal cord injury, cell therapy, non-human primates, humans, and bioengineering in spinal cord injury). From 110 retrieved articles, after two selection rounds based on inclusion and exclusion criteria, 21 articles were analyzed. Thus, this review arises from the need to recognize the experimental therapeutic advances applied in non-human primates and even humans, aimed at deepening these strategies and identifying the advantages and influence of the results on extrapolation for clinical applicability in humans.
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Affiliation(s)
- Ana Milena Silva Olaya
- PhD Program in Pathological Anatomy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Ana Maria Blanco Martinez
- Graduate Program in Pathological Anatomy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Suelen Adriani Marques
- Graduate Program in Pathological Anatomy (PPGAP/UFRJ), Department of Neurobiology/Institute of Biology, Campus do Gragoatá, Niterói, Rio de Janeiro, Brazil
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2
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Guérout N. Combined Treatments and Therapies to Cure Spinal Cord Injury. Biomedicines 2024; 12:1095. [PMID: 38791057 PMCID: PMC11118184 DOI: 10.3390/biomedicines12051095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2024] [Accepted: 05/14/2024] [Indexed: 05/26/2024] Open
Abstract
Traumatic injuries of the spinal cord (SCIs) are still pathologies with a disastrous outcome [...].
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Affiliation(s)
- Nicolas Guérout
- Saints Pères Paris Institute for the Neurosciences, Université Paris Cité, CNRS UMR8003, 75006 Paris, France
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3
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Fischer G, Bättig L, Stienen MN, Curt A, Fehlings MG, Hejrati N. Advancements in neuroregenerative and neuroprotective therapies for traumatic spinal cord injury. Front Neurosci 2024; 18:1372920. [PMID: 38812974 PMCID: PMC11133582 DOI: 10.3389/fnins.2024.1372920] [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: 01/18/2024] [Accepted: 04/10/2024] [Indexed: 05/31/2024] Open
Abstract
Traumatic spinal cord injuries (SCIs) continue to be a major healthcare concern, with a rising prevalence worldwide. In response to this growing medical challenge, considerable scientific attention has been devoted to developing neuroprotective and neuroregenerative strategies aimed at improving the prognosis and quality of life for individuals with SCIs. This comprehensive review aims to provide an up-to-date and thorough overview of the latest neuroregenerative and neuroprotective therapies currently under investigation. These strategies encompass a multifaceted approach that include neuropharmacological interventions, cell-based therapies, and other promising strategies such as biomaterial scaffolds and neuro-modulation therapies. In addition, the review discusses the importance of acute clinical management, including the role of hemodynamic management as well as timing and technical aspects of surgery as key factors mitigating the secondary injury following SCI. In conclusion, this review underscores the ongoing scientific efforts to enhance patient outcomes and quality of life, focusing on upcoming strategies for the management of traumatic SCI. Each section provides a working knowledge of the fundamental preclinical and patient trials relevant to clinicians while underscoring the pathophysiologic rationale for the therapies.
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Affiliation(s)
- Gregor Fischer
- Department of Neurosurgery, Cantonal Hospital St.Gallen, Medical School of St.Gallen, St.Gallen, Switzerland
- Spine Center of Eastern Switzerland, Cantonal Hospital St.Gallen, Medical School of St.Gallen, St.Gallen, Switzerland
| | - Linda Bättig
- Department of Neurosurgery, Cantonal Hospital St.Gallen, Medical School of St.Gallen, St.Gallen, Switzerland
- Spine Center of Eastern Switzerland, Cantonal Hospital St.Gallen, Medical School of St.Gallen, St.Gallen, Switzerland
| | - Martin N. Stienen
- Department of Neurosurgery, Cantonal Hospital St.Gallen, Medical School of St.Gallen, St.Gallen, Switzerland
- Spine Center of Eastern Switzerland, Cantonal Hospital St.Gallen, Medical School of St.Gallen, St.Gallen, Switzerland
| | - Armin Curt
- Spinal Cord Injury Center, University Hospital Balgrist, Zurich, Switzerland
| | - Michael G. Fehlings
- Division of Neurosurgery and Spine Program, Department of Surgery, University of Toronto, Toronto, ON, Canada
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
| | - Nader Hejrati
- Department of Neurosurgery, Cantonal Hospital St.Gallen, Medical School of St.Gallen, St.Gallen, Switzerland
- Spine Center of Eastern Switzerland, Cantonal Hospital St.Gallen, Medical School of St.Gallen, St.Gallen, Switzerland
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Kvistad CE, Kråkenes T, Gavasso S, Bø L. Neural regeneration in the human central nervous system-from understanding the underlying mechanisms to developing treatments. Where do we stand today? Front Neurol 2024; 15:1398089. [PMID: 38803647 PMCID: PMC11129638 DOI: 10.3389/fneur.2024.1398089] [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: 03/08/2024] [Accepted: 04/22/2024] [Indexed: 05/29/2024] Open
Abstract
Mature neurons in the human central nervous system (CNS) fail to regenerate after injuries. This is a common denominator across different aetiologies, including multiple sclerosis, spinal cord injury and ischemic stroke. The lack of regeneration leads to permanent functional deficits with a substantial impact on patient quality of life, representing a significant socioeconomic burden worldwide. Great efforts have been made to decipher the responsible mechanisms and we now know that potent intra- and extracellular barriers prevent axonal repair. This knowledge has resulted in numerous clinical trials, aiming to promote neuroregeneration through different approaches. Here, we summarize the current understanding of the causes to the poor regeneration within the human CNS. We also review the results of the treatment attempts that have been translated into clinical trials so far.
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Affiliation(s)
| | - Torbjørn Kråkenes
- Neuro-SysMed, Department of Neurology, Haukeland University Hospital, Bergen, Norway
| | - Sonia Gavasso
- Neuro-SysMed, Department of Neurology, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Medicine, University of Bergen, Bergen, Norway
| | - Lars Bø
- Neuro-SysMed, Department of Neurology, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Medicine, University of Bergen, Bergen, Norway
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Ozcicek I, Aysit N, Balcikanli Z, Ayturk NU, Aydeger A, Baydas G, Aydin MS, Altintas E, Erim UC. Development of BDNF/NGF/IKVAV Peptide Modified and Gold Nanoparticle Conductive PCL/PLGA Nerve Guidance Conduit for Regeneration of the Rat Spinal Cord Injury. Macromol Biosci 2024; 24:e2300453. [PMID: 38224015 DOI: 10.1002/mabi.202300453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 12/22/2023] [Indexed: 01/16/2024]
Abstract
Spinal cord injuries are very common worldwide, leading to permanent nerve function loss with devastating effects in the affected patients. The challenges and inadequate results in the current clinical treatments are leading scientists to innovative neural regenerative research. Advances in nanoscience and neural tissue engineering have opened new avenues for spinal cord injury (SCI) treatment. In order for designed nerve guidance conduit (NGC) to be functionally useful, it must have ideal scaffold properties and topographic features that promote the linear orientation of damaged axons. In this study, it is aimed to develop channeled polycaprolactone (PCL)/Poly-D,L-lactic-co-glycolic acid (PLGA) hybrid film scaffolds, modify their surfaces by IKVAV pentapeptide/gold nanoparticles (AuNPs) or polypyrrole (PPy) and investigate the behavior of motor neurons on the designed scaffold surfaces in vitro under static/bioreactor conditions. Their potential to promote neural regeneration after implantation into the rat SCI by shaping the film scaffolds modified with neural factors into a tubular form is also examined. It is shown that channeled groups decorated with AuNPs highly promote neurite orientation under bioreactor conditions and also the developed optimal NGC (PCL/PLGA G1-IKVAV/BDNF/NGF-AuNP50) highly regenerates SCI. The results indicate that the designed scaffold can be an ideal candidate for spinal cord regeneration.
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Affiliation(s)
- Ilyas Ozcicek
- Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, Istanbul, 34810, Turkey
- Department of Medical Biology, School of Medicine, Istanbul Medipol University, Istanbul, 34815, Turkey
| | - Nese Aysit
- Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, Istanbul, 34810, Turkey
- Department of Medical Biology, School of Medicine, Istanbul Medipol University, Istanbul, 34815, Turkey
| | - Zeynep Balcikanli
- Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, Istanbul, 34810, Turkey
| | - Nilufer Ulas Ayturk
- Department of Histology and Embryology, Faculty of Medicine, Çanakkale Onsekiz Mart University, Canakkale, 17020, Turkey
| | - Asel Aydeger
- Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, Istanbul, 34810, Turkey
- Graduate School of Health Sciences, Istanbul Medipol University, Istanbul, 34815, Turkey
| | - Gulsena Baydas
- Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, Istanbul, 34810, Turkey
- Graduate School of Health Sciences, Istanbul Medipol University, Istanbul, 34815, Turkey
- Department of Physiology, School of Medicine, Istanbul Medipol University, Istanbul, 34815, Turkey
| | - Mehmet Serif Aydin
- Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, Istanbul, 34810, Turkey
| | - Esra Altintas
- Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, Istanbul, 34810, Turkey
- Graduate School of Health Sciences, Istanbul Medipol University, Istanbul, 34815, Turkey
| | - Umit Can Erim
- Research Institute for Health Sciences and Technologies (SABITA), Istanbul Medipol University, Istanbul, 34810, Turkey
- Department of Analytical Chemistry, School of Pharmacy, Istanbul Medipol University, Istanbul, 34815, Turkey
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6
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Behnammoghadam M, Alimohammadi N, Riazi A, Eghbali-Babadi M, Rezvani M. Care needs of adults with spinal trauma in the prehospital and hospital setting from the perspective of patient care team: A qualitative research. JOURNAL OF EDUCATION AND HEALTH PROMOTION 2024; 13:83. [PMID: 38720688 PMCID: PMC11078458 DOI: 10.4103/jehp.jehp_282_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 04/26/2023] [Indexed: 05/12/2024]
Abstract
BACKGROUND Appropriate care of patients with definite spinal cord injury or at risk of it in the prehospital and hospital stages requires comprehensive planning in the health system. It is also the requirement of any successful program to explain the needs from the perspective of its stakeholders. Thus, this study aimed to discover the care needs of adults with spinal trauma in prehospital and hospital settings from the perspective of the patient care team. MATERIALS AND METHODS This qualitative study was conducted with the participation of urban and rural prehospital emergency personnel and emergency departments of educational and therapeutic hospitals affiliated to Isfahan, Tehran, Shiraz, Kermanshah, Ahvaz, and Yasuj Universities of Medical Sciences, through conducting 36 in-depth semi-structured interviews from September to December 2021. Using purposive sampling method, the participants were selected considering the maximum variation. The data saturation was reached after conducting interviews and group discussions with 36 subjects. Data were analyzed using conventional content analysis approach. Lundman and Graneheim approach were used for the study rigour. Data were simultaneously analyzed using MAXQDA software version 10. RESULT During the data analysis, two themes of prehospital care with two main categories (emergency care and management of secondary complications of spinal trauma) and hospital care with two main categories (emergency care and management of secondary complications of spinal trauma) emerged. CONCLUSION Emergency care and management of secondary complications of spinal cord injury in the prehospital and hospital stages can affect treatment results, improve quality of life, and reduce mortality rate, secondary injuries, and healthcare costs. Thus, identification of the care needs of the adults with spinal trauma from the perspective of the patient care team can help the authorities to plan appropriate interventions.
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Affiliation(s)
- Mohammad Behnammoghadam
- Department of Critical Care Nursing, Faculty of Nursing and Midwifery, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Nasrollah Alimohammadi
- Department of Critical Care Nursing, Faculty of Nursing and Midwifery, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Ali Riazi
- Department of Neurosurgery, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Maryam Eghbali-Babadi
- Department of Critical Care Nursing, Faculty of Nursing and Midwifery, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Majid Rezvani
- Department of Neurosurgery, Neurosciences Research Center, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
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Bourguignon L, Lukas LP, Guest JD, Geisler FH, Noonan V, Curt A, Brüningk SC, Jutzeler CR. Studying missingness in spinal cord injury data: challenges and impact of data imputation. BMC Med Res Methodol 2024; 24:5. [PMID: 38184529 PMCID: PMC10770973 DOI: 10.1186/s12874-023-02125-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 12/08/2023] [Indexed: 01/08/2024] Open
Abstract
BACKGROUND In the last decades, medical research fields studying rare conditions such as spinal cord injury (SCI) have made extensive efforts to collect large-scale data. However, most analysis methods rely on complete data. This is particularly troublesome when studying clinical data as they are prone to missingness. Often, researchers mitigate this problem by removing patients with missing data from the analyses. Less commonly, imputation methods to infer likely values are applied. OBJECTIVE Our objective was to study how handling missing data influences the results reported, taking the example of SCI registries. We aimed to raise awareness on the effects of missing data and provide guidelines to be applied for future research projects, in SCI research and beyond. METHODS Using the Sygen clinical trial data (n = 797), we analyzed the impact of the type of variable in which data is missing, the pattern according to which data is missing, and the imputation strategy (e.g. mean imputation, last observation carried forward, multiple imputation). RESULTS Our simulations show that mean imputation may lead to results strongly deviating from the underlying expected results. For repeated measures missing at late stages (> = 6 months after injury in this simulation study), carrying the last observation forward seems the preferable option for the imputation. This simulation study could show that a one-size-fit-all imputation strategy falls short in SCI data sets. CONCLUSIONS Data-tailored imputation strategies are required (e.g., characterisation of the missingness pattern, last observation carried forward for repeated measures evolving to a plateau over time). Therefore, systematically reporting the extent, kind and decisions made regarding missing data will be essential to improve the interpretation, transparency, and reproducibility of the research presented.
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Affiliation(s)
- Lucie Bourguignon
- Department of Health Sciences and Technology (D-HEST), ETH Zurich, Universitätstrasse 2, 8092, Zürich, Switzerland.
- Schulthess Klinik, Lengghalde 2, 8008, Zürich, Switzerland.
- SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland.
| | - Louis P Lukas
- Department of Health Sciences and Technology (D-HEST), ETH Zurich, Universitätstrasse 2, 8092, Zürich, Switzerland
- Schulthess Klinik, Lengghalde 2, 8008, Zürich, Switzerland
- SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - James D Guest
- Neurological Surgery and the Miami Project to Cure Paralysis, U Miami, Miami, FL, 33136, USA
| | - Fred H Geisler
- Department of Medical Imaging, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Vanessa Noonan
- Praxis Spinal Cord Institute, Vancouver, British Columbia, Canada
| | - Armin Curt
- Spinal Cord Injury Center, University Hospital Balgrist, University of Zurich, Lengghalde 2, 8006, Zürich, Switzerland
| | - Sarah C Brüningk
- Department of Health Sciences and Technology (D-HEST), ETH Zurich, Universitätstrasse 2, 8092, Zürich, Switzerland
- Schulthess Klinik, Lengghalde 2, 8008, Zürich, Switzerland
- SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Catherine R Jutzeler
- Department of Health Sciences and Technology (D-HEST), ETH Zurich, Universitätstrasse 2, 8092, Zürich, Switzerland
- Schulthess Klinik, Lengghalde 2, 8008, Zürich, Switzerland
- SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland
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8
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Balbinot G. Neuromodulation to guide circuit reorganization with regenerative therapies in upper extremity rehabilitation following cervical spinal cord injury. FRONTIERS IN REHABILITATION SCIENCES 2024; 4:1320211. [PMID: 38234989 PMCID: PMC10791849 DOI: 10.3389/fresc.2023.1320211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 12/12/2023] [Indexed: 01/19/2024]
Abstract
Spinal cord injury (SCI) is a profoundly debilitating condition with no effective treatment to date. The complex response of the central nervous system (CNS) to injury and its limited regeneration capacity pose bold challenges for restoring function. Cervical SCIs are the most prevalent and regaining hand function is a top priority for individuals living with cervical SCI. A promising avenue for addressing this challenge arises from the emerging field of regenerative rehabilitation, which combines regenerative biology with physical medicine approaches. The hypothesis for optimizing gains in upper extremity function centers on the integration of targeted neurorehabilitation with novel cell- and stem cell-based therapies. However, the precise roles and synergistic effects of these components remain poorly understood, given the intricate nature of SCI and the diversity of regenerative approaches. This perspective article sheds light on the current state of regenerative rehabilitation for cervical SCI. Notably, preclinical research has yet to fully incorporate rehabilitation protocols that mimic current clinical practices, which often rely on neuromodulation strategies to activate spared circuits below the injury level. Therefore, it becomes imperative to comprehensively investigate the combined effects of neuromodulation and regenerative medicine strategies in animal models before translating these therapies to individuals with SCI. In cases of severe upper extremity paralysis, the advent of neuromodulation strategies, such as corticospinal tract (CST) and spinal cord stimulation, holds promise as the next frontier in enhancing the effectiveness of cell- and stem cell-based therapies. Future preclinical studies should explore this convergence of neuromodulation and regenerative approaches to unlock new possibilities for upper extremity treatment after SCI.
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Affiliation(s)
- Gustavo Balbinot
- Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Center for Advancing Neurotechnological Innovation to Application, University of Toronto, Toronto, ON, Canada
- KITE Research Institute – Toronto Rehabilitation Institute, University Health Network, Toronto, ON, Canada
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Hirt J, Khanteymoori A, Hohenhaus M, Kopp MA, Howells DW, Schwab JM, Watzlawick R. Inhibition of the Nogo-pathway in experimental spinal cord injury: a meta-analysis of 76 experimental treatments. Sci Rep 2023; 13:22898. [PMID: 38129508 PMCID: PMC10739940 DOI: 10.1038/s41598-023-49260-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 12/06/2023] [Indexed: 12/23/2023] Open
Abstract
Recovery after spinal cord injury (SCI) may be propagated by plasticity-enhancing treatments. The myelin-associated nerve outgrowth inhibitor Nogo-A (Reticulon 4, RTN4) pathway has been shown to restrict neuroaxonal plasticity in experimental SCI models. Early randomized controlled trials are underway to investigate the effect of Nogo-A/Nogo-Receptor (NgR1) pathway blockers. This systematic review and meta-analysis of therapeutic approaches blocking the Nogo-A pathway interrogated the efficacy of functional locomotor recovery after experimental SCI according to a pre-registered study protocol. A total of 51 manuscripts reporting 76 experiments in 1572 animals were identified for meta-analysis. Overall, a neurobehavioral improvement by 18.9% (95% CI 14.5-23.2) was observed. Subgroup analysis (40 experiments, N = 890) revealed SCI-modelling factors associated with outcome variability. Lack of reported randomization and smaller group sizes were associated with larger effect sizes. Delayed treatment start was associated with lower effect sizes. Trim and Fill assessment as well as Egger regression suggested the presence of publication bias. Factoring in theoretically missing studies resulted in a reduced effect size [8.8% (95% CI 2.6-14.9)]. The available data indicates that inhibition of the Nogo-A/NgR1pathway alters functional recovery after SCI in animal studies although substantial differences appear for the applied injury mechanisms and other study details. Mirroring other SCI interventions assessed earlier we identify similar factors associated with outcome heterogeneity.
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Affiliation(s)
- Julian Hirt
- Department of Neurology and Experimental Neurology, Charité Campus Mitte, Clinical and Experimental Spinal Cord Injury Research Laboratory (Neuroparaplegiology), Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Alireza Khanteymoori
- Department of Neurosurgery, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Straße 64, 79106, Freiburg, Germany
| | - Marc Hohenhaus
- Department of Neurosurgery, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Straße 64, 79106, Freiburg, Germany
| | - Marcel A Kopp
- Department of Neurology and Experimental Neurology, Charité Campus Mitte, Clinical and Experimental Spinal Cord Injury Research Laboratory (Neuroparaplegiology), Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - David W Howells
- Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Melbourne, VIC, Australia
| | - Jan M Schwab
- Department of Neurology and Experimental Neurology, Charité Campus Mitte, Clinical and Experimental Spinal Cord Injury Research Laboratory (Neuroparaplegiology), Charité - Universitätsmedizin Berlin, Berlin, Germany
- Department of Neurology, Spinal Cord Injury Division (Paraplegiology), The Neurological Institute, The Ohio State University, Wexner Medical Center, Columbus, OH, USA
- Belford Center for Spinal Cord Injury, Departments of Neuroscience and Physical Medicine and Rehabilitation, The Neurological Institute, The Ohio State University, Wexner Medical Center, Columbus, OH, USA
| | - Ralf Watzlawick
- Department of Neurology and Experimental Neurology, Charité Campus Mitte, Clinical and Experimental Spinal Cord Injury Research Laboratory (Neuroparaplegiology), Charité - Universitätsmedizin Berlin, Berlin, Germany.
- Department of Neurosurgery, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Straße 64, 79106, Freiburg, Germany.
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10
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Chambel SS, Cruz CD. Axonal growth inhibitors and their receptors in spinal cord injury: from biology to clinical translation. Neural Regen Res 2023; 18:2573-2581. [PMID: 37449592 DOI: 10.4103/1673-5374.373674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2023] Open
Abstract
Axonal growth inhibitors are released during traumatic injuries to the adult mammalian central nervous system, including after spinal cord injury. These molecules accumulate at the injury site and form a highly inhibitory environment for axonal regeneration. Among these inhibitory molecules, myelin-associated inhibitors, including neurite outgrowth inhibitor A, oligodendrocyte myelin glycoprotein, myelin-associated glycoprotein, chondroitin sulfate proteoglycans and repulsive guidance molecule A are of particular importance. Due to their inhibitory nature, they represent exciting molecular targets to study axonal inhibition and regeneration after central injuries. These molecules are mainly produced by neurons, oligodendrocytes, and astrocytes within the scar and in its immediate vicinity. They exert their effects by binding to specific receptors, localized in the membranes of neurons. Receptors for these inhibitory cues include Nogo receptor 1, leucine-rich repeat, and Ig domain containing 1 and p75 neurotrophin receptor/tumor necrosis factor receptor superfamily member 19 (that form a receptor complex that binds all myelin-associated inhibitors), and also paired immunoglobulin-like receptor B. Chondroitin sulfate proteoglycans and repulsive guidance molecule A bind to Nogo receptor 1, Nogo receptor 3, receptor protein tyrosine phosphatase σ and leucocyte common antigen related phosphatase, and neogenin, respectively. Once activated, these receptors initiate downstream signaling pathways, the most common amongst them being the RhoA/ROCK signaling pathway. These signaling cascades result in actin depolymerization, neurite outgrowth inhibition, and failure to regenerate after spinal cord injury. Currently, there are no approved pharmacological treatments to overcome spinal cord injuries other than physical rehabilitation and management of the array of symptoms brought on by spinal cord injuries. However, several novel therapies aiming to modulate these inhibitory proteins and/or their receptors are under investigation in ongoing clinical trials. Investigation has also been demonstrating that combinatorial therapies of growth inhibitors with other therapies, such as growth factors or stem-cell therapies, produce stronger results and their potential application in the clinics opens new venues in spinal cord injury treatment.
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Affiliation(s)
- Sílvia Sousa Chambel
- Experimental Biology Unit, Department of Biomedicine, Faculty of Medicine of Porto; Translational NeuroUrology, Instituto de Investigação e Inovação em Saúde-i3S and IBMC, Universidade do Porto, Porto, Portugal
| | - Célia Duarte Cruz
- Experimental Biology Unit, Department of Biomedicine, Faculty of Medicine of Porto; Translational NeuroUrology, Instituto de Investigação e Inovação em Saúde-i3S and IBMC, Universidade do Porto, Porto, Portugal
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11
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Howard EM, Strittmatter SM. Development of neural repair therapy for chronic spinal cord trauma: soluble Nogo receptor decoy from discovery to clinical trial. Curr Opin Neurol 2023; 36:516-522. [PMID: 37865850 PMCID: PMC10841037 DOI: 10.1097/wco.0000000000001205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2023]
Abstract
PURPOSE OF REVIEW After traumatic spinal cord injury (SCI), neurological deficits persist due to the disconnection of surviving neurons. While repair of connectivity may restore function, no medical therapy exists today.This review traces the development of the neural repair-based therapeutic AXER-204 from animal studies to the recent clinical trial for chronic cervical SCI. RECENT FINDINGS Molecular studies reveal a Nogo-66 Receptor 1 (NgR1, RTN4R) pathway inhibiting axon regeneration, sprouting, and plasticity in the adult mammalian central nervous system (CNS). Rodent and nonhuman primate studies demonstrate that the soluble receptor decoy NgR(310)ecto-Fc or AXER-204 promotes neural repair and functional recovery in transection and contusion SCI. Recently, this biological agent completed a first-in-human and randomized clinical trial for chronic cervical SCI. The intervention was safe and well tolerated. Across all participants, upper extremity strength did not improve with treatment. However, posthoc and biomarker analyses suggest that AXER-204 may benefit treatment-naïve patients with incomplete SCI in the chronic stage. SUMMARY NgR1 signaling restricts neurological recovery in animal studies of CNS injury. The recent clinical trial of AXER-204 provides encouraging signals supporting future focused trials of this neural repair therapeutic. Further, AXER-204 studies provide a roadmap for the development of additional and synergistic therapies for chronic SCI.
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Affiliation(s)
- Elisa M. Howard
- Departments of Neuroscience and Neurology, Yale School of Medicine, New Haven, CT, USA
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12
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Schellhammer L, Beffinger M, Salazar U, Laman JD, Buch T, vom Berg J. Exit pathways of therapeutic antibodies from the brain and retention strategies. iScience 2023; 26:108132. [PMID: 37915602 PMCID: PMC10616392 DOI: 10.1016/j.isci.2023.108132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2023] Open
Abstract
Treating brain diseases requires therapeutics to pass the blood-brain barrier (BBB) which is nearly impermeable for large biologics such as antibodies. Several methods now facilitate crossing or circumventing the BBB for antibody therapeutics. Some of these exploit receptor-mediated transcytosis, others use direct delivery bypassing the BBB. However, successful delivery into the brain does not preclude exit back to the systemic circulation. Various mechanisms are implicated in the active and passive export of antibodies from the central nervous system. Here we review findings on active export via transcytosis of therapeutic antibodies - in particular, the role of the neonatal Fc receptor (FcRn) - and discuss a possible contribution of passive efflux pathways such as lymphatic and perivascular drainage. We point out open questions and how to address these experimentally. In addition, we suggest how emerging findings could aid the design of the next generation of therapeutic antibodies for neurologic diseases.
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Affiliation(s)
- Linda Schellhammer
- Institute of Laboratory Animal Science, University of Zurich, 8952 Schlieren, Switzerland
| | - Michal Beffinger
- Institute of Laboratory Animal Science, University of Zurich, 8952 Schlieren, Switzerland
- InCephalo AG, 4123 Allschwil, Switzerland
| | - Ulisse Salazar
- Institute of Laboratory Animal Science, University of Zurich, 8952 Schlieren, Switzerland
| | - Jon D. Laman
- Department of Pathology & Medical Biology, University of Groningen, University Medical Center Groningen, Groningen 9713, the Netherlands
| | - Thorsten Buch
- Institute of Laboratory Animal Science, University of Zurich, 8952 Schlieren, Switzerland
| | - Johannes vom Berg
- Institute of Laboratory Animal Science, University of Zurich, 8952 Schlieren, Switzerland
- InCephalo AG, 4123 Allschwil, Switzerland
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13
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Chen LM, Wang F, Mishra A, Yang PF, Sengupta A, Reed JL, Gore JC. Longitudinal multiparametric MRI of traumatic spinal cord injury in animal models. Magn Reson Imaging 2023; 102:184-200. [PMID: 37343904 PMCID: PMC10528214 DOI: 10.1016/j.mri.2023.06.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 06/14/2023] [Accepted: 06/17/2023] [Indexed: 06/23/2023]
Abstract
Multi-parametric MRI (mpMRI) technology enables non-invasive and quantitative assessments of the structural, molecular, and functional characteristics of various neurological diseases. Despite the recognized importance of studying spinal cord pathology, mpMRI applications in spinal cord research have been somewhat limited, partly due to technical challenges associated with spine imaging. However, advances in imaging techniques and improved image quality now allow longitudinal investigations of a comprehensive range of spinal cord pathological features by exploiting different endogenous MRI contrasts. This review summarizes the use of mpMRI techniques including blood oxygenation level-dependent (BOLD) functional MRI (fMRI), diffusion tensor imaging (DTI), quantitative magnetization transfer (qMT), and chemical exchange saturation transfer (CEST) MRI in monitoring different aspects of spinal cord pathology. These aspects include cyst formation and axonal disruption, demyelination and remyelination, changes in the excitability of spinal grey matter and the integrity of intrinsic functional circuits, and non-specific molecular changes associated with secondary injury and neuroinflammation. These approaches are illustrated with reference to a nonhuman primate (NHP) model of traumatic cervical spinal cord injuries (SCI). We highlight the benefits of using NHP SCI models to guide future studies of human spinal cord pathology, and demonstrate how mpMRI can capture distinctive features of spinal cord pathology that were previously inaccessible. Furthermore, the development of mechanism-based MRI biomarkers from mpMRI studies can provide clinically useful imaging indices for understanding the mechanisms by which injured spinal cords progress and repair. These biomarkers can assist in the diagnosis, prognosis, and evaluation of therapies for SCI patients, potentially leading to improved outcomes.
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Affiliation(s)
- Li Min Chen
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA.
| | - Feng Wang
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Arabinda Mishra
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Pai-Feng Yang
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Anirban Sengupta
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Jamie L Reed
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
| | - John C Gore
- Vanderbilt University Institute of Imaging Science, Vanderbilt University, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
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14
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Powers BE, Ton ST, Farrer RG, Chaudhary S, Nockels RP, Kartje GL, Tsai SY. Anti-Nogo-A Antibody Therapy Improves Functional Outcome Following Traumatic Brain Injury. Neurorehabil Neural Repair 2023; 37:682-693. [PMID: 37837331 PMCID: PMC10843026 DOI: 10.1177/15459683231203194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2023]
Abstract
BACKGROUND Traumatic brain injury (TBI) can cause sensorimotor deficits, and recovery is slow and incomplete. There are no effective pharmacological treatments for recovery from TBI, but research indicates potential for anti-Nogo-A antibody (Ab) therapy. This Ab neutralizes Nogo-A, an endogenous transmembrane protein that inhibits neuronal plasticity and regeneration. OBJECTIVE We hypothesized that anti-Nogo-A Ab treatment following TBI results in disinhibited axonal growth from the contralesional cortex, the establishment of new compensatory neuronal connections, and improved function. METHODS We modeled TBI in rats using the controlled cortical impact method, resulting in focal brain damage and motor deficits like those observed in humans with a moderate cortical TBI. Rats were trained on the skilled forelimb reaching task and the horizontal ladder rung walking task. They were then given a TBI, targeting the caudal forelimb motor cortex, and randomly divided into 3 groups: TBI-only, TBI + Anti-Nogo-A Ab, and TBI + Control Ab. Testing resumed 3 days after TBI and continued for 8 weeks, when rats received an injection of the anterograde neuronal tracer, biotinylated dextran amine (BDA), into the corresponding area contralateral to the TBI. RESULTS We observed significant improvement in rats that received anti-Nogo-A Ab treatment post-TBI compared to controls. Analysis of BDA-positive axons revealed that anti-Nogo-A Ab treatment resulted in cortico-rubral plasticity to the deafferented red nucleus. Conclusions. Anti-Nogo-A Ab treatment may improve functional recovery via neuronal plasticity to brain areas important for skilled movements, and this treatment shows promise to improve outcomes in humans who have suffered a TBI.
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Affiliation(s)
- Brian E Powers
- Edward Hines Jr. Veteran Affairs Hospital, Hines, IL, USA
| | - Son T Ton
- Edward Hines Jr. Veteran Affairs Hospital, Hines, IL, USA
| | | | | | - Russ P Nockels
- Department of Neurological Surgery, Loyola University Medical Center, Maywood, IL, USA
| | - Gwendolyn L Kartje
- Edward Hines Jr. Veteran Affairs Hospital, Hines, IL, USA
- Department of Molecular Pharmacology and Neuroscience, Loyola University Health Sciences Division, Maywood, IL, USA
| | - Shih-Yen Tsai
- Edward Hines Jr. Veteran Affairs Hospital, Hines, IL, USA
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15
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Tian T, Zhang S, Yang M. Recent progress and challenges in the treatment of spinal cord injury. Protein Cell 2023; 14:635-652. [PMID: 36856750 PMCID: PMC10501188 DOI: 10.1093/procel/pwad003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 12/29/2022] [Indexed: 02/12/2023] Open
Abstract
Spinal cord injury (SCI) disrupts the structural and functional connectivity between the higher center and the spinal cord, resulting in severe motor, sensory, and autonomic dysfunction with a variety of complications. The pathophysiology of SCI is complicated and multifaceted, and thus individual treatments acting on a specific aspect or process are inadequate to elicit neuronal regeneration and functional recovery after SCI. Combinatory strategies targeting multiple aspects of SCI pathology have achieved greater beneficial effects than individual therapy alone. Although many problems and challenges remain, the encouraging outcomes that have been achieved in preclinical models offer a promising foothold for the development of novel clinical strategies to treat SCI. In this review, we characterize the mechanisms underlying axon regeneration of adult neurons and summarize recent advances in facilitating functional recovery following SCI at both the acute and chronic stages. In addition, we analyze the current status, remaining problems, and realistic challenges towards clinical translation. Finally, we consider the future of SCI treatment and provide insights into how to narrow the translational gap that currently exists between preclinical studies and clinical practice. Going forward, clinical trials should emphasize multidisciplinary conversation and cooperation to identify optimal combinatorial approaches to maximize therapeutic benefit in humans with SCI.
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Affiliation(s)
- Ting Tian
- Ministry of Education Key Laboratory of Protein Science, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Sensen Zhang
- Ministry of Education Key Laboratory of Protein Science, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Maojun Yang
- Ministry of Education Key Laboratory of Protein Science, Beijing Advanced Innovation Center for Structural Biology, Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Cryo-EM Facility Center, Southern University of Science and Technology, Shenzhen 518055, China
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16
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Kelly-Hedrik M, Abd-El-Barr MM, Aarabi B, Curt A, Howley SP, Harrop JS, Kirshblum S, Neal CJ, Noonan V, Park C, Ugiliweneza B, Tator C, Toups EG, Fehlings MG, Williamson T, Guest JD. Importance of Prospective Registries and Clinical Research Networks in the Evolution of Spinal Cord Injury Care. J Neurotrauma 2023; 40:1834-1848. [PMID: 36576020 DOI: 10.1089/neu.2022.0450] [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] [Indexed: 12/29/2022] Open
Abstract
Only 100 years ago, traumatic spinal cord injury (SCI) was commonly lethal. Today, most people who sustain SCI survive with continual efforts to improve their quality of life and neurological outcomes. SCI epidemiology is changing as preventative interventions reduce injuries in younger individuals, and there is an increased incidence of incomplete injuries in aging populations. Early treatment has become more intensive with decompressive surgery and proactive interventions to improve spinal cord perfusion. Accurate data, including specialized outcome measures, are crucial to understanding the impact of epidemiological and treatment trends. Dedicated SCI clinical research and data networks and registries have been established in the United States, Canada, Europe, and several other countries. We review four registry networks: the North American Clinical Trials Network (NACTN) SCI Registry, the National Spinal Cord Injury Model Systems (SCIMS) Database, the Rick Hansen SCI Registry (RHSCIR), and the European Multi-Center Study about Spinal Cord Injury (EMSCI). We compare the registries' focuses, data platforms, advanced analytics use, and impacts. We also describe how registries' data can be combined with electronic health records (EHRs) or shared using federated analysis to protect registrants' identities. These registries have identified changes in epidemiology, recovery patterns, complication incidence, and the impact of practice changes such as early decompression. They've also revealed latent disease-modifying factors, helped develop clinical trial stratification models, and served as matched control groups in clinical trials. Advancing SCI clinical science for personalized medicine requires advanced analytical techniques, including machine learning, counterfactual analysis, and the creation of digital twins. Registries and other data sources help drive innovation in SCI clinical science.
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Affiliation(s)
| | | | - Bizhan Aarabi
- University of Maryland School of Medicine, Maryland, USA
| | - Armin Curt
- Spinal Cord Injury Center, Balgrist University Hospital, Zurich, Switzerland
| | - Susan P Howley
- Christopher & Dana Reeve Foundation, Short Hills, New Jersey, USA
| | - James S Harrop
- Thomas Jefferson University Hospital, Philadelphia, Pennsylvania, USA
| | - Steven Kirshblum
- Rutgers New Jersey Medical School, Newark, New Jersey, USA
- Kessler Institute for Rehabilitation, West Orange, New Jersey, USA
- Kessler Foundation, West Orange, New Jersey, USA
| | - Christopher J Neal
- Division of Neurosurgery, Walter Reed National Military Medical Center, Bethesda, Maryland, USA
| | - Vanessa Noonan
- Praxis Spinal Cord Institute, Vancouver, British Columbia, Canada
| | - Christine Park
- Duke University School of Medicine, Durham, North Carolina, USA
| | | | - Charles Tator
- Division of Neurosurgery and Spine Program, Department of Surgery, University of Toronto, Toronto, Ontario, Canada
| | - Elizabeth G Toups
- Department of Neurosurgery, Houston Methodist Hospital, Houston, Texas, USA
| | - Michael G Fehlings
- Division of Neurosurgery and Spine Program, Department of Surgery, University of Toronto, Toronto, Ontario, Canada
| | - Theresa Williamson
- Department of Neurosurgery, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - James D Guest
- Neurological Surgery and The Miami Project to Cure Paralysis, University of Miami, Miami, USA
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17
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Punjani N, Deska-Gauthier D, Hachem LD, Abramian M, Fehlings MG. Neuroplasticity and regeneration after spinal cord injury. NORTH AMERICAN SPINE SOCIETY JOURNAL 2023; 15:100235. [PMID: 37416090 PMCID: PMC10320621 DOI: 10.1016/j.xnsj.2023.100235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 06/05/2023] [Accepted: 06/05/2023] [Indexed: 07/08/2023]
Abstract
Spinal cord injury (SCI) is a debilitating condition with significant personal, societal, and economic burden. The highest proportion of traumatic injuries occur at the cervical level, which results in severe sensorimotor and autonomic deficits. Following the initial physical damage associated with traumatic injuries, secondary pro-inflammatory, excitotoxic, and ischemic cascades are initiated further contributing to neuronal and glial cell death. Additionally, emerging evidence has begun to reveal that spinal interneurons undergo subtype specific neuroplastic circuit rearrangements in the weeks to months following SCI, contributing to or hindering functional recovery. The current therapeutic guidelines and standards of care for SCI patients include early surgery, hemodynamic regulation, and rehabilitation. Additionally, preclinical work and ongoing clinical trials have begun exploring neuroregenerative strategies utilizing endogenous neural stem/progenitor cells, stem cell transplantation, combinatorial approaches, and direct cell reprogramming. This review will focus on emerging cellular and noncellular regenerative therapies with an overview of the current available strategies, the role of interneurons in plasticity, and the exciting research avenues enhancing tissue repair following SCI.
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Affiliation(s)
- Nayaab Punjani
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Dylan Deska-Gauthier
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Laureen D. Hachem
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- Department of Surgery, Division of Neurosurgery and Spine Program, University of Toronto, Toronto, ON, Canada
| | - Madlene Abramian
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Michael G. Fehlings
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- Department of Surgery, Division of Neurosurgery and Spine Program, University of Toronto, Toronto, ON, Canada
- Division of Neurosurgery, Krembil Neuroscience Centre, Toronto Western Hospital, University Health Network, Toronto, ON, Canada
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18
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Maynard G, Kannan R, Liu J, Wang W, Lam TKT, Wang X, Adamson C, Hackett C, Schwab JM, Liu C, Leslie DP, Chen D, Marino R, Zafonte R, Flanders A, Block G, Smith E, Strittmatter SM. Soluble Nogo-Receptor-Fc decoy (AXER-204) in patients with chronic cervical spinal cord injury in the USA: a first-in-human and randomised clinical trial. Lancet Neurol 2023; 22:672-684. [PMID: 37479373 PMCID: PMC10410101 DOI: 10.1016/s1474-4422(23)00215-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 05/13/2023] [Accepted: 06/02/2023] [Indexed: 07/23/2023]
Abstract
BACKGROUND Spinal cord injury (SCI) causes neural disconnection and persistent neurological deficits, so axon sprouting and plasticity might promote recovery. Soluble Nogo-Receptor-Fc decoy (AXER-204) blocks inhibitors of axon growth and promotes recovery of motor function after SCI in animals. This first-in-human and randomised trial sought to determine primarily the safety and pharmacokinetics of AXER-204 in individuals with chronic SCI, and secondarily its effect on recovery. METHODS We conducted a two-part study in adults (aged 18-65 years) with chronic (>1 year) cervical traumatic SCI at six rehabilitation centres in the USA. In part 1, AXER-204 was delivered open label as single intrathecal doses of 3 mg, 30 mg, 90 mg, or 200 mg, with primary outcomes of safety and pharmacokinetics. Part 2 was a randomised, parallel, double-blind comparison of six intrathecal doses of 200 mg AXER-204 over 104 days versus placebo. Participants were randomly allocated (1:1) by investigators using a central electronic system, stratified in blocks of four by American Spinal Injury Association Impairment Scale grade and receipt of AXER-204 in part 1. All investigators and patients were masked to treatment allocation until at least day 169. The part 2 primary objectives were safety and pharmacokinetics, with a key secondary objective to assess change in International Standards for Neurological Classification of SCI (ISNCSCI) Upper Extremity Motor Score (UEMS) at day 169 for all enrolled participants. This trial is registered with ClinicalTrials.gov, NCT03989440, and is completed. FINDINGS We treated 24 participants in part 1 (six per dose; 18 men, six women), and 27 participants in part 2 (13 placebo, 14 AXER-204; 23 men, four women), between June 20, 2019, and June 21, 2022. There were no deaths and no discontinuations from the study due to an adverse event in part 1 and 2. In part 2, treatment-related adverse events were of similar incidence in AXER-204 and placebo groups (ten [71%] vs nine [69%]). Headache was the most common treatment-related adverse event (five [21%] in part 1, 11 [41%] in part 2). In part 1, AXER-204 reached mean maximal CSF concentration 1 day after dosing with 200 mg of 412 000 ng/mL (SD 129 000), exceeding those concentrations that were efficacious in animal studies. In part 2, mean changes from baseline to day 169 in ISNCSCI UEMS were 1·5 (SD 3·3) for AXER-204 and 0·9 (2·3) for placebo (mean difference 0·54, 95% CI -1·48 to 2·55; p=0·59). INTERPRETATION This study delivers the first, to our knowledge, clinical trial of a rationally designed pharmacological treatment intended to promote neural repair in chronic SCI. AXER-204 appeared safe and reached target CSF concentrations; exploratory biomarker results were consistent with target engagement and synaptic stabilisation. Post-hoc subgroup analyses suggest that future trials could investigate efficacy in patients with moderately severe SCI without prior AXER-204 exposure. FUNDING Wings for Life Foundation, National Institute of Neurological Disorders and Stroke, National Center for Advancing Translational Sciences, National Institute on Drug Abuse, and ReNetX Bio.
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Affiliation(s)
| | - Ramakrishnan Kannan
- Departments of Neuroscience and Neurology, Yale School of Medicine, New Haven, CT, USA
| | - Jian Liu
- Departments of Neuroscience and Neurology, Yale School of Medicine, New Haven, CT, USA
| | - Weiwei Wang
- Keck MS and Proteomic Resource, Yale School of Medicine, New Haven, CT, USA
| | - Tu Kiet T Lam
- Keck MS and Proteomic Resource, Yale School of Medicine, New Haven, CT, USA; Department of Molecular Biophysics and Biochemistry, Yale School of Medicine, New Haven, CT, USA
| | - Xingxing Wang
- Departments of Neuroscience and Neurology, Yale School of Medicine, New Haven, CT, USA
| | | | | | - Jan M Schwab
- Belford Center for Spinal Cord Injury and Departments of Neurology and Neuroscience, The Ohio State University, Wexner Medical Center, Columbus, OH, USA
| | - Charles Liu
- USC Neurorestoration Center, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | | | - David Chen
- Shirley Ryan AbilityLab, Chicago, IL, USA
| | - Ralph Marino
- Department of Rehabilitation Medicine, Thomas Jefferson University, Philadelphia, PA, USA
| | - Ross Zafonte
- Spaulding Rehabilitation Hospital, Massachusetts General Hospital, Brigham and Womens Hospital, Harvard Medical School, Boston, MA, USA
| | - Adam Flanders
- Department of Rehabilitation Medicine, Thomas Jefferson University, Philadelphia, PA, USA
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19
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Dave BP, Shah KC, Shah MB, Chorawala MR, Patel VN, Shah PA, Shah GB, Dhameliya TM. Unveiling the modulation of Nogo receptor in neuroregeneration and plasticity: Novel aspects and future horizon in a new frontier. Biochem Pharmacol 2023; 210:115461. [PMID: 36828272 DOI: 10.1016/j.bcp.2023.115461] [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: 12/21/2022] [Revised: 02/16/2023] [Accepted: 02/17/2023] [Indexed: 02/25/2023]
Abstract
Neurodegenerative diseases (NDs) such as Alzheimer's, Parkinson's, Multiple Sclerosis, Hereditary Spastic Paraplegia, and Amyotrophic Lateral Sclerosis have emerged as the most dreaded diseases due to a lack of precise diagnostic tools and efficient therapies. Despite the fact that the contributing factors of NDs are still unidentified, mounting evidence indicates the possibility that genetic and cellular changes may lead to the significant production of abnormally misfolded proteins. These misfolded proteins lead to damaging effects thereby causing neurodegeneration. The association between Neurite outgrowth factor (Nogo) with neurological diseases and other peripheral diseases is coming into play. Three isoforms of Nogo have been identified Nogo-A, Nogo-B and Nogo-C. Among these, Nogo-A is mainly responsible for neurological diseases as it is localized in the CNS (Central Nervous System), whereas Nogo-B and Nogo-C are responsible for other diseases such as colitis, lung, intestinal injury, etc. Nogo-A, a membrane protein, had first been described as a CNS-specific inhibitor of axonal regeneration. Several recent studies have revealed the role of Nogo-A proteins and their receptors in modulating neurite outgrowth, branching, and precursor migration during nervous system development. It may also modulate or affect the inhibition of growth during the developmental processes of the CNS. Information about the effects of other ligands of Nogo protein on the CNS are yet to be discovered however several pieces of evidence have suggested that it may also influence the neuronal maturation of CNS and targeting Nogo-A could prove to be beneficial in several neurodegenerative diseases.
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Affiliation(s)
- Bhavarth P Dave
- Department of Pharmacology and Pharmacy Practice, L. M. College of Pharmacy, Opp. Gujarat University, Ahmedabad 380009, Gujarat, India
| | - Kashvi C Shah
- Department of Pharmacology and Pharmacy Practice, L. M. College of Pharmacy, Opp. Gujarat University, Ahmedabad 380009, Gujarat, India
| | - Maitri B Shah
- Department of Pharmacology and Pharmacy Practice, L. M. College of Pharmacy, Opp. Gujarat University, Ahmedabad 380009, Gujarat, India
| | - Mehul R Chorawala
- Department of Pharmacology and Pharmacy Practice, L. M. College of Pharmacy, Opp. Gujarat University, Ahmedabad 380009, Gujarat, India.
| | - Vishvas N Patel
- Department of Pharmacology and Pharmacy Practice, L. M. College of Pharmacy, Opp. Gujarat University, Ahmedabad 380009, Gujarat, India
| | - Palak A Shah
- Department of Pharmacology, K. B. Institute of Pharmaceutical Education and Research, Gandhinagar 380023, Gujarat, India
| | - Gaurang B Shah
- Department of Pharmacology and Pharmacy Practice, L. M. College of Pharmacy, Opp. Gujarat University, Ahmedabad 380009, Gujarat, India
| | - Tejas M Dhameliya
- Department of Pharmaceutical Chemistry, Institute of Pharmacy, Nirma University, Ahmedabad-382481, Gujarat, India
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20
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Nogo-A and LINGO-1: Two Important Targets for Remyelination and Regeneration. Int J Mol Sci 2023; 24:ijms24054479. [PMID: 36901909 PMCID: PMC10003089 DOI: 10.3390/ijms24054479] [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: 01/24/2023] [Revised: 02/13/2023] [Accepted: 02/22/2023] [Indexed: 02/26/2023] Open
Abstract
Multiple sclerosis (MS) is an inflammatory disease of the central nervous system (CNS) that causes progressive neurological disability in most patients due to neurodegeneration. Activated immune cells infiltrate the CNS, triggering an inflammatory cascade that leads to demyelination and axonal injury. Non-inflammatory mechanisms are also involved in axonal degeneration, although they are not fully elucidated yet. Current therapies focus on immunosuppression; however, no therapies to promote regeneration, myelin repair, or maintenance are currently available. Two different negative regulators of myelination have been proposed as promising targets to induce remyelination and regeneration, namely the Nogo-A and LINGO-1 proteins. Although Nogo-A was first discovered as a potent neurite outgrowth inhibitor in the CNS, it has emerged as a multifunctional protein. It is involved in numerous developmental processes and is necessary for shaping and later maintaining CNS structure and functionality. However, the growth-restricting properties of Nogo-A have negative effects on CNS injury or disease. LINGO-1 is also an inhibitor of neurite outgrowth, axonal regeneration, oligodendrocyte differentiation, and myelin production. Inhibiting the actions of Nogo-A or LINGO-1 promotes remyelination both in vitro and in vivo, while Nogo-A or LINGO-1 antagonists have been suggested as promising therapeutic approaches for demyelinating diseases. In this review, we focus on these two negative regulators of myelination while also providing an overview of the available data on the effects of Nogo-A and LINGO-1 inhibition on oligodendrocyte differentiation and remyelination.
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21
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Sterner RC, Sterner RM. Immune response following traumatic spinal cord injury: Pathophysiology and therapies. Front Immunol 2023; 13:1084101. [PMID: 36685598 PMCID: PMC9853461 DOI: 10.3389/fimmu.2022.1084101] [Citation(s) in RCA: 24] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Accepted: 12/19/2022] [Indexed: 01/09/2023] Open
Abstract
Traumatic spinal cord injury (SCI) is a devastating condition that is often associated with significant loss of function and/or permanent disability. The pathophysiology of SCI is complex and occurs in two phases. First, the mechanical damage from the trauma causes immediate acute cell dysfunction and cell death. Then, secondary mechanisms of injury further propagate the cell dysfunction and cell death over the course of days, weeks, or even months. Among the secondary injury mechanisms, inflammation has been shown to be a key determinant of the secondary injury severity and significantly worsens cell death and functional outcomes. Thus, in addition to surgical management of SCI, selectively targeting the immune response following SCI could substantially decrease the progression of secondary injury and improve patient outcomes. In order to develop such therapies, a detailed molecular understanding of the timing of the immune response following SCI is necessary. Recently, several studies have mapped the cytokine/chemokine and cell proliferation patterns following SCI. In this review, we examine the immune response underlying the pathophysiology of SCI and assess both current and future therapies including pharmaceutical therapies, stem cell therapy, and the exciting potential of extracellular vesicle therapy.
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Affiliation(s)
- Robert C. Sterner
- School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, United States
| | - Rosalie M. Sterner
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States,*Correspondence: Rosalie M. Sterner,
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22
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Tang H, Gu Y, Jiang L, Zheng G, Pan Z, Jiang X. The role of immune cells and associated immunological factors in the immune response to spinal cord injury. Front Immunol 2023; 13:1070540. [PMID: 36685599 PMCID: PMC9849245 DOI: 10.3389/fimmu.2022.1070540] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Accepted: 12/05/2022] [Indexed: 01/06/2023] Open
Abstract
Spinal cord injury (SCI) is a devastating neurological condition prevalent worldwide. Where the pathological mechanisms underlying SCI are concerned, we can distinguish between primary injury caused by initial mechanical damage and secondary injury characterized by a series of biological responses, such as vascular dysfunction, oxidative stress, neurotransmitter toxicity, lipid peroxidation, and immune-inflammatory response. Secondary injury causes further tissue loss and dysfunction, and the immune response appears to be the key molecular mechanism affecting injured tissue regeneration and functional recovery from SCI. Immune response after SCI involves the activation of different immune cells and the production of immunity-associated chemicals. With the development of new biological technologies, such as transcriptomics, the heterogeneity of immune cells and chemicals can be classified with greater precision. In this review, we focus on the current understanding of the heterogeneity of these immune components and the roles they play in SCI, including reactive astrogliosis and glial scar formation, neutrophil migration, macrophage transformation, resident microglia activation and proliferation, and the humoral immunity mediated by T and B cells. We also summarize findings from clinical trials of immunomodulatory therapies for SCI and briefly review promising therapeutic drugs currently being researched.
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Affiliation(s)
- Huaguo Tang
- Department of Hand and Foot Surgery, Zhejiang Rongjun Hospital, Jiaxing, China
| | - Yuanjie Gu
- Department of Hand and Foot Surgery, Zhejiang Rongjun Hospital, Jiaxing, China
| | - Lei Jiang
- Department of Hand and Foot Surgery, Zhejiang Rongjun Hospital, Jiaxing, China
| | - Gang Zheng
- Department of Neurosurgery, The Central Hospital Affiliated to Shaoxing University, Jiaxing, China
| | - Zhuoer Pan
- Department of Orthopedics, Zhejiang Rongjun Hospital, Jiaxing, China
| | - Xiugui Jiang
- Department of Hand and Foot Surgery, Zhejiang Rongjun Hospital, Jiaxing, China,*Correspondence: Xiugui Jiang,
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Schwaiger C, Haider T, Endmayr V, Zrzavy T, Gruber VE, Ricken G, Simonovska A, Hametner S, Schwab JM, Höftberger R. Dynamic induction of the myelin-associated growth inhibitor Nogo-A in perilesional plasticity regions after human spinal cord injury. Brain Pathol 2023; 33:e13098. [PMID: 35698271 PMCID: PMC9836369 DOI: 10.1111/bpa.13098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Accepted: 05/29/2022] [Indexed: 01/21/2023] Open
Abstract
The myelin-associated inhibitor Nogo-A (Reticulon 4, RTN4) restricts axonal outgrowth, plasticity, and neural circuitry formation in experimental models of spinal cord injury (SCI) and is targeted in clinical interventions starting treatment within 4 weeks post-SCI. Specifically, Nogo-A expressed by oligodendroglia restricts compensatory neurite sprouting. To interrogate the hypothesis of an inducible, lesion reactive Nogo-A expression over time, we analyzed the spatiotemporal Nogo-A expression at the spinal lesion core (region of tissue necrosis and axonal damage/pruning) and perilesional rim (region of plasticity formation). Spinal cord specimens of SCI subjects (n = 22) were compared to neuropathologically unaltered controls (n = 9). Nogo-A expression was investigated ranging from acute (0-3 days), early subacute (4-21 days), late subacute (22-90 days) to early chronic-chronic (91 days to 1.5 years after SCI) stages after SCI. Nogo-A expression in controls is confined to motoneurons in the anterior horn and to oligodendrocytes in gray and white matter. After SCI, the number of Nogo-A+ and TPPP/p25+ oligodendrocytes (i) inclined at the organizing perilesional rim specifically, (ii) increased further over time, and (iii) peaked at chronic stages after SCI. By contrast, at the lesion core, the number of Nogo-A+ and TPPP/p25+ oligodendrocytes did not increase. Increasing numbers of Nogo-A+ oligodendrocytes coincided with oligodendrogenesis corroborated by Nogo-A coexpression of Ki67+ , TPPP/p25+ proliferating oligodendrocytes. Nogo-A oligodendrocyte expression emerges at perilesional (plasticity) regions over time and suggests an extended therapeutical window for anti-Nogo-A pathway targeting interventions beyond 4 weeks in patients after SCI.
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Affiliation(s)
- Carmen Schwaiger
- Division of Neuropathology and Neurochemistry, Department of NeurologyMedical University of ViennaViennaAustria
| | - Thomas Haider
- Department of Orthopedics and Trauma SurgeryMedical University of ViennaViennaAustria
| | - Verena Endmayr
- Division of Neuropathology and Neurochemistry, Department of NeurologyMedical University of ViennaViennaAustria
| | - Tobias Zrzavy
- Department of NeurologyMedical University of ViennaViennaAustria
| | - Victoria E. Gruber
- Department of Pediatrics and Adolescent MedicineMedical University of Vienna (Affiliated Partner of the ERN EpiCARE)ViennaAustria
| | - Gerda Ricken
- Division of Neuropathology and Neurochemistry, Department of NeurologyMedical University of ViennaViennaAustria
| | - Anika Simonovska
- Center for Medical Physics and Biomedical EngineeringMedical University of ViennaViennaAustria
| | - Simon Hametner
- Division of Neuropathology and Neurochemistry, Department of NeurologyMedical University of ViennaViennaAustria
| | - Jan M. Schwab
- The Belford Center for Spinal Cord Injury and Departments of Neurology, Physical Medicine and Rehabilitation and NeurosciencesThe Ohio State UniversityColumbusOhioUSA
| | - Romana Höftberger
- Division of Neuropathology and Neurochemistry, Department of NeurologyMedical University of ViennaViennaAustria
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Almeida F, Marques S, Santos A, Prins C, Cardoso F, Heringer L, Mendonça H, Martinez A. Molecular approaches for spinal cord injury treatment. Neural Regen Res 2023; 18:23-30. [PMID: 35799504 PMCID: PMC9241396 DOI: 10.4103/1673-5374.344830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Injuries to the spinal cord result in permanent disabilities that limit daily life activities. The main reasons for these poor outcomes are the limited regenerative capacity of central neurons and the inhibitory milieu that is established upon traumatic injuries. Despite decades of research, there is still no efficient treatment for spinal cord injury. Many strategies are tested in preclinical studies that focus on ameliorating the functional outcomes after spinal cord injury. Among these, molecular compounds are currently being used for neurological recovery, with promising results. These molecules target the axon collapsed growth cone, the inhibitory microenvironment, the survival of neurons and glial cells, and the re-establishment of lost connections. In this review we focused on molecules that are being used, either in preclinical or clinical studies, to treat spinal cord injuries, such as drugs, growth and neurotrophic factors, enzymes, and purines. The mechanisms of action of these molecules are discussed, considering traumatic spinal cord injury in rodents and humans.
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25
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Wang H, Zhang H, Xie Z, Chen K, Ma M, Huang Y, Li M, Cai Z, Wang P, Shen H. Injectable hydrogels for spinal cord injury repair. ENGINEERED REGENERATION 2022. [DOI: 10.1016/j.engreg.2022.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Fehlings MG, Pedro K, Hejrati N. Management of Acute Spinal Cord Injury: Where Have We Been? Where Are We Now? Where Are We Going? J Neurotrauma 2022; 39:1591-1602. [PMID: 35686453 DOI: 10.1089/neu.2022.0009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Affiliation(s)
- Michael G Fehlings
- Division of Genetics and Development, Krembil Brain Institute, University Health Network, Toronto, Ontario, Canada.,Institute of Medical Science, Department of Surgery, University of Toronto, Toronto, Ontario, Canada.,Division of Neurosurgery and Spine Program, Department of Surgery, University of Toronto, Toronto, Ontario, Canada
| | - Karlo Pedro
- Division of Neurosurgery and Spine Program, Department of Surgery, University of Toronto, Toronto, Ontario, Canada
| | - Nader Hejrati
- Division of Genetics and Development, Krembil Brain Institute, University Health Network, Toronto, Ontario, Canada.,Division of Neurosurgery and Spine Program, Department of Surgery, University of Toronto, Toronto, Ontario, Canada
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Wu Y, Tang Z, Zhang J, Wang Y, Liu S. Restoration of spinal cord injury: From endogenous repairing process to cellular therapy. Front Cell Neurosci 2022; 16:1077441. [PMID: 36523818 PMCID: PMC9744968 DOI: 10.3389/fncel.2022.1077441] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Accepted: 11/08/2022] [Indexed: 09/26/2023] Open
Abstract
Spinal cord injury (SCI) disrupts neurological pathways and impacts sensory, motor, and autonomic nerve function. There is no effective treatment for SCI currently. Numerous endogenous cells, including astrocytes, macrophages/microglia, and oligodendrocyte, are involved in the histological healing process following SCI. By interfering with cells during the SCI repair process, some advancements in the therapy of SCI have been realized. Nevertheless, the endogenous cell types engaged in SCI repair and the current difficulties these cells confront in the therapy of SCI are poorly defined, and the mechanisms underlying them are little understood. In order to better understand SCI and create new therapeutic strategies and enhance the clinical translation of SCI repair, we have comprehensively listed the endogenous cells involved in SCI repair and summarized the six most common mechanisms involved in SCI repair, including limiting the inflammatory response, protecting the spared spinal cord, enhancing myelination, facilitating neovascularization, producing neurotrophic factors, and differentiating into neural/colloidal cell lines.
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Affiliation(s)
| | | | | | | | - Shengwen Liu
- Department of Neurosurgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Lima R, Monteiro A, Salgado AJ, Monteiro S, Silva NA. Pathophysiology and Therapeutic Approaches for Spinal Cord Injury. Int J Mol Sci 2022; 23:ijms232213833. [PMID: 36430308 PMCID: PMC9698625 DOI: 10.3390/ijms232213833] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 11/07/2022] [Indexed: 11/12/2022] Open
Abstract
Spinal cord injury (SCI) is a disabling condition that disrupts motor, sensory, and autonomic functions. Despite extensive research in the last decades, SCI continues to be a global health priority affecting thousands of individuals every year. The lack of effective therapeutic strategies for patients with SCI reflects its complex pathophysiology that leads to the point of no return in its function repair and regeneration capacity. Recently, however, several studies started to uncover the intricate network of mechanisms involved in SCI leading to the development of new therapeutic approaches. In this work, we present a detailed description of the physiology and anatomy of the spinal cord and the pathophysiology of SCI. Additionally, we provide an overview of different molecular strategies that demonstrate promising potential in the modulation of the secondary injury events that promote neuroprotection or neuroregeneration. We also briefly discuss other emerging therapies, including cell-based therapies, biomaterials, and epidural electric stimulation. A successful therapy might target different pathologic events to control the progression of secondary damage of SCI and promote regeneration leading to functional recovery.
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Affiliation(s)
- Rui Lima
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal
- ICVS/3B’s Associate Laboratory, PT Government Associated Laboratory, 4806-909 Braga/Guimarães, Portugal
| | - Andreia Monteiro
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal
- ICVS/3B’s Associate Laboratory, PT Government Associated Laboratory, 4806-909 Braga/Guimarães, Portugal
| | - António J. Salgado
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal
- ICVS/3B’s Associate Laboratory, PT Government Associated Laboratory, 4806-909 Braga/Guimarães, Portugal
| | - Susana Monteiro
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal
- ICVS/3B’s Associate Laboratory, PT Government Associated Laboratory, 4806-909 Braga/Guimarães, Portugal
| | - Nuno A. Silva
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal
- ICVS/3B’s Associate Laboratory, PT Government Associated Laboratory, 4806-909 Braga/Guimarães, Portugal
- Correspondence:
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Taylor MJ, Thompson AM, Alhajlah S, Tuxworth RI, Ahmed Z. Inhibition of Chk2 promotes neuroprotection, axon regeneration, and functional recovery after CNS injury. SCIENCE ADVANCES 2022; 8:eabq2611. [PMID: 36103534 PMCID: PMC9473583 DOI: 10.1126/sciadv.abq2611] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 07/29/2022] [Indexed: 06/15/2023]
Abstract
DNA double-strand breaks occur in many acute and long-term neurological conditions, including neurodegeneration, neurotrauma, and stroke. Nonrepaired breaks chronically activate the DNA damage response in neurons, leading to neural dysfunction and apoptosis. Here, we show that targeting of the central ATM-Chk2 pathway regulating the response to double-strand breaks slows neural decline in Drosophila models of chronic neurodegeneration. Inhibitors of ATM-Chk2, but not the parallel ATR-Chk1 pathway, also promote marked, functional recovery after acute central nervous system injury in rats, suggesting that inhibiting nonhomologous end-joining rather than homologous recombination is crucial for neuroprotection. We demonstrate that the Chk2 inhibitor, prexasertib, which has been evaluated in phase 2 clinical trials for cancer, has potent neuroprotective effects and represents a new treatment option to promote functional recovery after spinal cord or optic nerve injury.
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Affiliation(s)
- Matthew J. Taylor
- Institute of Cancer and Genomic Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Adam M. Thompson
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Sharif Alhajlah
- Applied Medical Science College, Shaqra University, Addawadmi, Riyadh, Saudi Arabia
| | - Richard I. Tuxworth
- Institute of Cancer and Genomic Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Zubair Ahmed
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
- Centre for Trauma Sciences Research, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
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Thomas AX, Riviello JJ, Davila-Williams D, Thomas SP, Erklauer JC, Bauer DF, Cokley JA. Pharmacologic and Acute Management of Spinal Cord Injury in Adults and Children. Curr Treat Options Neurol 2022; 24:285-304. [PMID: 35702419 PMCID: PMC9184374 DOI: 10.1007/s11940-022-00720-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/14/2022] [Indexed: 11/26/2022]
Abstract
Purpose of Review This review provides guidance for acute spinal cord injury (SCI) management through an analytical assessment of the most recent evidence on therapies available for treating SCI, including newer therapies under investigation. We present an approach to the SCI patient starting at presentation to acute rehabilitation and prognostication, with additional emphasis on the pediatric population when evidence is available. Recent Findings Further studies since the Surgical Timing in Acute Spinal Cord Injury Study (STASCIS) demonstrated a potential functional outcome benefit with ultra-early surgical intervention ≤ 8 h post-SCI. Subsequent analysis of the National Acute Spinal Cord Injury Study (NASCIS) II and NASCIS III trials have demonstrated potentially serious complications from intravenous methylprednisolone with limited benefit. Newer therapies actively being studied have demonstrated limited or no benefit in preclinical and clinical trials with insufficient evidence to support use in acute SCI treatment. Summary Care for SCI patients requires a multi-disciplinary team. Immediate evaluation and management are focused on preventing additional injury and restoring perfusion to the affected cord. Rapid assessment and intervention involve focused neurological examination, targeted imaging, and surgical intervention when indicated. There are currently no evidence-based recommendations for pathomechanistically targeted therapies.
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Affiliation(s)
- Ajay X. Thomas
- Division of Pediatric Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, TX USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX USA
| | - James J. Riviello
- Division of Pediatric Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, TX USA
| | - Daniel Davila-Williams
- Division of Pediatric Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, TX USA
| | - Sruthi P. Thomas
- Division of Pediatric Physical Medicine and Rehabilitation, Department of Physical Medicine and Rehabilitation, Baylor College of Medicine, Houston, TX USA
- Division of Pediatric Neurosurgery, Department of Neurosurgery, Baylor College of Medicine, Houston, TX USA
| | - Jennifer C. Erklauer
- Division of Pediatric Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, TX USA
- Division of Pediatric Critical Care Medicine, Department of Pediatrics, Baylor College of Medicine, Houston, TX USA
| | - David F. Bauer
- Division of Pediatric Neurosurgery, Department of Neurosurgery, Baylor College of Medicine, Houston, TX USA
| | - Jon A. Cokley
- Division of Pediatric Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, TX USA
- Department of Pharmacy, Baylor College of Medicine, Houston, TX USA
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Feng Y, Li Y, Shen PP, Wang B. Gene-Modified Stem Cells for Spinal Cord Injury: a Promising Better Alternative Therapy. Stem Cell Rev Rep 2022; 18:2662-2682. [PMID: 35587330 DOI: 10.1007/s12015-022-10387-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/07/2022] [Indexed: 12/18/2022]
Abstract
Stem cell therapy holds great promise for the treatment of spinal cord injury (SCI), which can reverse neurodegeneration and promote tissue regeneration via its pluripotency and ability to secrete neurotrophic factors. Although various stem cell-based approaches have shown certain therapeutic effects when applied to the treatment of SCI, their clinical efficacies have been disappointing. Thus, it is an urgent need to further enhance the neurological benefits of stem cells through bioengineering strategies including genetic engineering. In this review, we summarize the progress of stem cell therapy for SCI and the prospect of genetically modified stem cells, focusing on the genome editing tools and functional molecules involved in SCI repair, trying to provide a deeper understanding of genetically modified stem cell therapy and more applicable clinical strategies for SCI repair.
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Affiliation(s)
- Yirui Feng
- Clinical Stem Cell Center, the Affiliated Drum Tower Hospital of Nanjing University Medical School, School of Life Science, Nanjing University, Nanjing, Jiangsu Province, China
| | - Yu Li
- Clinical Stem Cell Center, the Affiliated Drum Tower Hospital of Nanjing University Medical School, School of Life Science, Nanjing University, Nanjing, Jiangsu Province, China
| | - Ping-Ping Shen
- State Key Laboratory of Pharmaceutical Biotechnology and the Comprehensive Cancer Center, the Affiliated Drum Tower Hospital of Nanjing University Medical School, School of Life Science, Nanjing University, Nanjing, Jiangsu Province, China.
| | - Bin Wang
- Clinical Stem Cell Center, the Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, Jiangsu Province, China.
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Nogo-A Is a Potential Prognostic Marker for Spinal Cord Injury. DISEASE MARKERS 2022; 2022:2141854. [PMID: 35571610 PMCID: PMC9095389 DOI: 10.1155/2022/2141854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 04/11/2022] [Accepted: 04/15/2022] [Indexed: 11/30/2022]
Abstract
Objective Spinal cord injury (SCI) has become prevalent worldwide in recent years, and its prognosis is poor and the pathological mechanism has not been fully elucidated. Nogo-A is one of the isoforms of the neurite outgrowth inhibitory protein reticulon 4. The purpose of this study was to determine whether Nogo-A could be used as a marker for predicting the prognosis of SCI. Methods We screened eligible SCI patients and controls based on inclusion and exclusion criteria. We also collected baseline clinical information and peripheral venous blood of the enrolled population. Participants' baseline serum Nogo-A levels were measured by enzyme-linked immunosorbent assay (ELISA). The American Spinal Injury Association (ASIA) scale was used to evaluate the prognosis of SCI patients after 3 months. Results Baseline clinical information (age; gender; smoking; drinking; SBP, systolic blood pressure; DBP, diastolic blood pressure; fasting blood glucose; WBC, white blood cells; CRP, C-reactive protein) of SCI patients and controls were not statistically significant academic differences (p > 0.05). The baseline serum Nogo-A levels of SCI patients and controls were 192.7 ± 13.9 ng/ml and 263.1 ± 22.4 ng/ml, respectively, and there was a statistically significant difference between the two groups (p < 0.05). We divided SCI patients into 4 groups according to their baseline serum Nogo-A quartile levels and analyzed their relationship with ASIA scores. The trend test results showed that with the increase of Nogo-A level, the ASIA sensation score and ASIA motor score were significantly decreased (p < 0.001). Multivariate regression analysis showed that serum Nogo-A levels remained a potential cause affecting the prognosis of SCI after adjusting for confounding factors in multiple models. Conclusions Serum Nogo-A levels were significantly elevated in SCI patients. Moreover, elevated Nogo-A levels often indicate poor prognosis and can be used as a marker to predict the prognosis of SCI.
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Progression in translational research on spinal cord injury based on microenvironment imbalance. Bone Res 2022; 10:35. [PMID: 35396505 PMCID: PMC8993811 DOI: 10.1038/s41413-022-00199-9] [Citation(s) in RCA: 60] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 11/14/2021] [Accepted: 12/22/2021] [Indexed: 02/07/2023] Open
Abstract
Spinal cord injury (SCI) leads to loss of motor and sensory function below the injury level and imposes a considerable burden on patients, families, and society. Repair of the injured spinal cord has been recognized as a global medical challenge for many years. Significant progress has been made in research on the pathological mechanism of spinal cord injury. In particular, with the development of gene regulation, cell sequencing, and cell tracing technologies, in-depth explorations of the SCI microenvironment have become more feasible. However, translational studies related to repair of the injured spinal cord have not yielded significant results. This review summarizes the latest research progress on two aspects of SCI pathology: intraneuronal microenvironment imbalance and regenerative microenvironment imbalance. We also review repair strategies for the injured spinal cord based on microenvironment imbalance, including medications, cell transplantation, exosomes, tissue engineering, cell reprogramming, and rehabilitation. The current state of translational research on SCI and future directions are also discussed. The development of a combined, precise, and multitemporal strategy for repairing the injured spinal cord is a potential future direction.
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Inositol Polyphosphate-5-Phosphatase K ( Inpp5k) Enhances Sprouting of Corticospinal Tract Axons after CNS Trauma. J Neurosci 2022; 42:2190-2204. [PMID: 35135857 PMCID: PMC8936595 DOI: 10.1523/jneurosci.0897-21.2022] [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: 04/27/2021] [Revised: 01/13/2022] [Accepted: 01/14/2022] [Indexed: 11/21/2022] Open
Abstract
Failure of CNS neurons to mount a significant growth response after trauma contributes to chronic functional deficits after spinal cord injury. Activator and repressor screening of embryonic cortical neurons and retinal ganglion cells in vitro and transcriptional profiling of developing CNS neurons harvested in vivo have identified several candidates that stimulate robust axon growth in vitro and in vivo Building on these studies, we sought to identify novel axon growth activators induced in the complex adult CNS environment in vivo We transcriptionally profiled intact sprouting adult corticospinal neurons (CSNs) after contralateral pyramidotomy (PyX) in nogo receptor-1 knock-out mice and found that intact CSNs were enriched in genes in the 3-phosphoinositide degradation pathway, including six 5-phosphatases. We explored whether inositol polyphosphate-5-phosphatase K (Inpp5k) could enhance corticospinal tract (CST) axon growth in preclinical models of acute and chronic CNS trauma. Overexpression of Inpp5k in intact adult CSNs in male and female mice enhanced the sprouting of intact CST terminals after PyX and cortical stroke and sprouting of CST axons after acute and chronic severe thoracic spinal contusion. We show that Inpp5k stimulates axon growth in part by elevating the density of active cofilin in labile growth cones, thus stimulating actin polymerization and enhancing microtubule protrusion into distal filopodia. We identify Inpp5k as a novel CST growth activator capable of driving compensatory axon growth in multiple complex CNS injury environments and underscores the veracity of using in vivo transcriptional screening to identify the next generation of cell-autonomous factors capable of repairing the damaged CNS.SIGNIFICANCE STATEMENT Neurologic recovery is limited after spinal cord injury as CNS neurons are incapable of self-repair post-trauma. In vitro screening strategies exploit the intrinsically high growth capacity of embryonic CNS neurons to identify novel axon growth activators. While promising candidates have been shown to stimulate axon growth in vivo, concomitant functional recovery remains incomplete. We identified Inpp5k as a novel axon growth activator using transcriptional profiling of intact adult corticospinal tract (CST) neurons that had initiated a growth response after pyramidotomy in plasticity sensitized nogo receptor-1-null mice. Here, we show that Inpp5k overexpression can stimulate CST axon growth after pyramidotomy, stroke, and acute and chronic contusion injuries. These data support in vivo screening approaches to identify novel axon growth activators.
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Franz S, Rust L, Heutehaus L, Rupp R, Schuld C, Weidner N. Impact of Heterotopic Ossification on Functional Recovery in Acute Spinal Cord Injury. Front Cell Neurosci 2022; 16:842090. [PMID: 35221928 PMCID: PMC8864137 DOI: 10.3389/fncel.2022.842090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 01/17/2022] [Indexed: 12/14/2022] Open
Abstract
Objective: In spinal cord injury (SCI), heterotopic ossification is a frequent secondary complication, commonly associated with limited range of motion of affected joints, which could lead to secondary disability in activities of daily living. Additionally, heterotopic ossifications might challenge the effect of regeneration-promoting therapies on neurological and functional recovery. This study evaluated the impact of heterotopic ossification on clinical recovery within the first year after SCI. Methods: The study was conducted as a monocentric longitudinal paired cohort study. Recruitment was based on consecutive sampling in the framework of the European Multicenter about Spinal Cord Injury (EMSCI). Recovery profiles were determined using standardized neurological and functional clinical assessments within the 1st year following SCI. All study participants underwent at least two comprehensive standardized neurological and functional clinical examinations according to the International Standards for Neurological Classification of SCI and the Spinal Cord Independence Measure, respectively. Data regarding the diagnosis and treatment of heterotopic ossification were obtained by reviewing the patient medical records. The most similar “digital twin” from the entire EMSCI database were matched in terms of age, acute neurological and functional status to each individual with SCI, and heterotopic ossification. Results: Out of 25 participants diagnosed with heterotopic ossification, 13 individuals were enrolled and matched to control individuals. Most individuals presented with motor complete injury (75%). Ossifications were most frequently located at the hip joints (92%) and mainly occurred within the first 3 months after SCI. Individuals with heterotopic ossification achieved around 40% less functional improvement over time compared to their matched counterparts, whereas neurological recovery was not altered in individuals with SCI and heterotopic ossification. Conclusion: Heterotopic ossification—a common complication of SCI—unfavorably affects functional recovery, which in the end is most relevant for the best possible degree of independence in activities of daily living. Upon presentation with heterotopic ossification, neurological improvement achieved through potential restorative therapies might not translate into clinically meaningful functional improvement. Diagnostic algorithms and effective early prevention/treatment options for heterotopic ossification need to be established to ensure the best possible functional outcome. Clinical Trial Registration: NCT01571531 (https://clinicaltrials.gov).
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Affiliation(s)
- Steffen Franz
- Spinal Cord Injury Center, Heidelberg University Hospital, Heidelberg, Germany
| | - Lukas Rust
- Spinal Cord Injury Center, Heidelberg University Hospital, Heidelberg, Germany
| | - Laura Heutehaus
- Spinal Cord Injury Center, Heidelberg University Hospital, Heidelberg, Germany
| | - Rüdiger Rupp
- Spinal Cord Injury Center, Heidelberg University Hospital, Heidelberg, Germany
| | - Christian Schuld
- Spinal Cord Injury Center, Heidelberg University Hospital, Heidelberg, Germany
| | - Norbert Weidner
- Spinal Cord Injury Center, Heidelberg University Hospital, Heidelberg, Germany
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Estrada V, Oldenburg E, Popa O, Muller HW. Mapping the long rocky road to effective spinal cord injury therapy - A meta-review of pre-clinical and clinical research. J Neurotrauma 2022; 39:591-612. [PMID: 35196894 DOI: 10.1089/neu.2021.0298] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Spinal cord injury (SCI) is a rare condition, which even after decades of research, to date still presents an incurable condition with a complex symptomatology. SCI can result in paralysis, pain, loss of sensation, bladder and sexual dysfunction, and muscle degeneration to name but a few. The large number of publications makes it difficult to keep track of current progress in the field and of the many treatment options, which have been suggested and are being proposed with increasing frequency. Scientific databases with user-oriented search options will offer possible solutions, but they are still mostly in the development phase. In this meta-analysis, we summarize and narrow down SCI therapeutic approaches applied in pre-clinical and clinical research. Statistical analyses of treatment clusters - assorted after counting annual publication numbers in PubMed and ClinicalTrials.gov databases - were performed to allow the comparison of research foci and of their translation efficacy into clinical therapy. Using the example of SCI research, our findings demonstrate the challenges that come with the accelerating research progress - an issue, which many research fields are faced with today. The analyses point out similarities and differences in the prioritization of SCI research in pre-clinical versus clinical therapy strategies. Moreover, the results demonstrate the rapidly growing importance of modern (bio-)engineering technologies.
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Affiliation(s)
- Veronica Estrada
- Heinrich Heine University Düsseldorf, 9170, Neurology, Molecular Neurobiology Laboratory, Düsseldorf, Germany;
| | - Ellen Oldenburg
- Heinrich Heine University Düsseldorf, 9170, Institute of Quantitative and Theoretical Biology, Düsseldorf, Germany;
| | - Ovidiu Popa
- Heinrich Heine University Düsseldorf, 9170, Institute of Quantitative and Theoretical Biology, Düsseldorf, Germany;
| | - Hans W Muller
- Heinrich Heine University Düsseldorf, 9170, Neurology, Düsseldorf, Germany;
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37
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Thakre PP, Sunshine MD, Fuller DD. Spinally delivered ampakine CX717 increases phrenic motor output in adult rats. Respir Physiol Neurobiol 2022; 296:103814. [PMID: 34775071 PMCID: PMC9235873 DOI: 10.1016/j.resp.2021.103814] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 11/01/2021] [Accepted: 11/07/2021] [Indexed: 02/03/2023]
Abstract
Ampakines are synthetic molecules that allosterically modulate AMPA-type glutamate receptors. We tested the hypothesis that delivery of ampakines to the intrathecal space could stimulate neural drive to the diaphragm. Ampakine CX717 (20 mM, dissolved in 10 % HPCD) or an HPCD vehicle solution were delivered via a catheter placed in the intrathecal space at the fourth cervical segment in urethane-anesthetized, mechanically ventilated adult male Sprague-Dawley rats. The electrical activity of the phrenic nerve was recorded for 60-minutes following drug application. Intrathecal application of CX717 produced a gradual and sustained increase in phrenic inspiratory burst amplitude (n = 10). In contrast, application of HPCD (n = 10) caused no sustained change in phrenic motor output. Phrenic burst rate, heart rate, and mean arterial pressure were similar between CX717 and HPCD treated rats. We conclude that intrathecally delivered ampakines can modulate phrenic motor output. This approach may have value for targeted induction of spinal neuroplasticity in the context of neurorehabiliation.
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Affiliation(s)
- Prajwal P. Thakre
- Department of Physical Therapy, University of Florida, Gainesville, FL,Breathing Research and Therapeutics Center, University of Florida, Gainesville, FL,McKnight Brain Institute, University of Florida, Gainesville, FL
| | - Michael D. Sunshine
- Department of Physical Therapy, University of Florida, Gainesville, FL,Breathing Research and Therapeutics Center, University of Florida, Gainesville, FL,McKnight Brain Institute, University of Florida, Gainesville, FL
| | - David D. Fuller
- Department of Physical Therapy, University of Florida, Gainesville, FL,Breathing Research and Therapeutics Center, University of Florida, Gainesville, FL,McKnight Brain Institute, University of Florida, Gainesville, FL,Corresponding author: David D. Fuller, Department of Physical Therapy, University of Florida, 1149 Newell Drive, Gainesville, FL 32611
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38
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Innocenti GM. Defining neuroplasticity. HANDBOOK OF CLINICAL NEUROLOGY 2022; 184:3-18. [PMID: 35034744 DOI: 10.1016/b978-0-12-819410-2.00001-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Neuroplasticity, i.e., the modifiability of the brain, is different in development and adulthood. The first includes changes in: (i) neurogenesis and control of neuron number; (ii) neuronal migration; (iii) differentiation of the somato-dendritic and axonal phenotypes; (iv) formation of connections; (v) cytoarchitectonic differentiation. These changes are often interrelated and can lead to: (vi) system-wide modifications of brain structure as well as to (vii) acquisition of specific functions such as ocular dominance or language. Myelination appears to be plastic both in development and adulthood, at least, in rodents. Adult neuroplasticity is limited, and is mainly expressed as changes in the strength of excitatory and inhibitory synapses while the attempts to regenerate connections have met with limited success. The outcomes of neuroplasticity are not necessarily adaptive, but can also be the cause of neurological and psychiatric pathologies.
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39
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Co-Expression of Nogo-A in Dopaminergic Neurons of the Human Substantia Nigra Pars Compacta Is Reduced in Parkinson’s Disease. Cells 2021; 10:cells10123368. [PMID: 34943877 PMCID: PMC8699585 DOI: 10.3390/cells10123368] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 11/19/2021] [Accepted: 11/27/2021] [Indexed: 12/21/2022] Open
Abstract
Parkinson’s disease is mainly characterized by a progressive loss of dopaminergic neurons in the substantia nigra pars compacta. Together with the small number, the high vulnerability of the dopaminergic neurons is a major pathogenic culprit of Parkinson’s disease. Our previous findings of a higher survival of dopaminergic neurons in the substantia nigra co-expressing Nogo-A in an animal model of Parkinson’s disease suggested that Nogo-A may be associated with dopaminergic neurons resilience against Parkinson’s disease neurodegeneration. In the present study, we have addressed the expression of Nogo-A in the dopaminergic neurons in the substantia nigra in postmortem specimens of diseased and non-diseased subjects of different ages. For this purpose, in a collaborative effort we developed a tissue micro array (TMA) that allows for simultaneous staining of many samples in a single run. Interestingly, and in contrast to the observations gathered during normal aging and in the animal model of Parkinson’s disease, increasing age was significantly associated with a lower co-expression of Nogo-A in nigral dopaminergic neurons of patients with Parkinson’s disease. In sum, while Nogo-A expression in dopaminergic neurons is higher with increasing age, the opposite is the case in Parkinson’s disease. These observations suggest that Nogo-A might play a substantial role in the vulnerability of dopaminergic neurons in Parkinson’s disease.
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40
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NogoA-expressing astrocytes limit peripheral macrophage infiltration after ischemic brain injury in primates. Nat Commun 2021; 12:6906. [PMID: 34824275 PMCID: PMC8617297 DOI: 10.1038/s41467-021-27245-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 11/05/2021] [Indexed: 11/08/2022] Open
Abstract
Astrocytes play critical roles after brain injury, but their precise function is poorly defined. Utilizing single-nuclei transcriptomics to characterize astrocytes after ischemic stroke in the visual cortex of the marmoset monkey, we observed nearly complete segregation between stroke and control astrocyte clusters. Screening for the top 30 differentially expressed genes that might limit stroke recovery, we discovered that a majority of astrocytes expressed RTN4A/ NogoA, a neurite-outgrowth inhibitory protein previously only associated with oligodendrocytes. NogoA upregulation on reactive astrocytes post-stroke was significant in both the marmoset and human brain, whereas only a marginal change was observed in mice. We determined that NogoA mediated an anti-inflammatory response which likely contributes to limiting the infiltration of peripheral macrophages into the surviving parenchyma.
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41
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Zhang H, Liu Y, Zhou K, Wei W, Liu Y. Restoring Sensorimotor Function Through Neuromodulation After Spinal Cord Injury: Progress and Remaining Challenges. Front Neurosci 2021; 15:749465. [PMID: 34720867 PMCID: PMC8551759 DOI: 10.3389/fnins.2021.749465] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 09/13/2021] [Indexed: 12/27/2022] Open
Abstract
Spinal cord injury (SCI) is a major disability that results in motor and sensory impairment and extensive complications for the affected individuals which not only affect the quality of life of the patients but also result in a heavy burden for their families and the health care system. Although there are few clinically effective treatments for SCI, research over the past few decades has resulted in several novel treatment strategies which are related to neuromodulation. Neuromodulation-the use of neuromodulators, electrical stimulation or optogenetics to modulate neuronal activity-can substantially promote the recovery of sensorimotor function after SCI. Recent studies have shown that neuromodulation, in combination with other technologies, can allow paralyzed patients to carry out intentional, controlled movement, and promote sensory recovery. Although such treatments hold promise for completely overcoming SCI, the mechanisms by which neuromodulation has this effect have been difficult to determine. Here we review recent progress relative to electrical neuromodulation and optogenetics neuromodulation. We also examine potential mechanisms by which these methods may restore sensorimotor function. We then highlight the strengths of these approaches and remaining challenges with respect to its application.
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Affiliation(s)
- Hui Zhang
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Yaping Liu
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Kai Zhou
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Wei Wei
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
| | - Yaobo Liu
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China
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42
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Seáñez I, Capogrosso M. Motor improvements enabled by spinal cord stimulation combined with physical training after spinal cord injury: review of experimental evidence in animals and humans. Bioelectron Med 2021; 7:16. [PMID: 34706778 PMCID: PMC8555080 DOI: 10.1186/s42234-021-00077-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 09/30/2021] [Indexed: 12/20/2022] Open
Abstract
Electrical spinal cord stimulation (SCS) has been gaining momentum as a potential therapy for motor paralysis in consequence of spinal cord injury (SCI). Specifically, recent studies combining SCS with activity-based training have reported unprecedented improvements in motor function in people with chronic SCI that persist even without stimulation. In this work, we first provide an overview of the critical scientific advancements that have led to the current uses of SCS in neurorehabilitation: e.g. the understanding that SCS activates dormant spinal circuits below the lesion by recruiting large-to-medium diameter sensory afferents within the posterior roots. We discuss how this led to the standardization of implant position which resulted in consistent observations by independent clinical studies that SCS in combination with physical training promotes improvements in motor performance and neurorecovery. While all reported participants were able to move previously paralyzed limbs from day 1, recovery of more complex motor functions was gradual, and the timeframe for first observations was proportional to the task complexity. Interestingly, individuals with SCI classified as AIS B and C regained motor function in paralyzed joints even without stimulation, but not individuals with motor and sensory complete SCI (AIS A). Experiments in animal models of SCI investigating the potential mechanisms underpinning this neurorecovery suggest a synaptic reorganization of cortico-reticulo-spinal circuits that correlate with improvements in voluntary motor control. Future experiments in humans and animal models of paralysis will be critical to understand the potential and limits for functional improvements in people with different types, levels, timeframes, and severities of SCI.
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Affiliation(s)
- Ismael Seáñez
- Biomedical Engineering, Washington University in St. Louis, St. Louis, USA. .,Neurosurgery, Washington University School of Medicine in St. Louis, St. Louis, USA.
| | - Marco Capogrosso
- Neurological Surgery, University of Pittsburgh, Pittsburgh, USA.,Department of Physical Medicine and Rehabilitation, Rehab and Neural Engineering Labs, University of Pittsburgh, Pittsburgh, USA.,Department of Bioengineering, University of Pittsburgh, Pittsburgh, USA
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43
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Peterson SL, Li Y, Sun CJ, Wong KA, Leung KS, de Lima S, Hanovice NJ, Yuki K, Stevens B, Benowitz LI. Retinal Ganglion Cell Axon Regeneration Requires Complement and Myeloid Cell Activity within the Optic Nerve. J Neurosci 2021; 41:8508-8531. [PMID: 34417332 PMCID: PMC8513703 DOI: 10.1523/jneurosci.0555-21.2021] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 07/21/2021] [Accepted: 08/16/2021] [Indexed: 01/01/2023] Open
Abstract
Axon regenerative failure in the mature CNS contributes to functional deficits following many traumatic injuries, ischemic injuries, and neurodegenerative diseases. The complement cascade of the innate immune system responds to pathogen threat through inflammatory cell activation, pathogen opsonization, and pathogen lysis, and complement is also involved in CNS development, neuroplasticity, injury, and disease. Here, we investigated the involvement of the classical complement cascade and microglia/monocytes in CNS repair using the mouse optic nerve injury (ONI) model, in which axons arising from retinal ganglion cells (RGCs) are disrupted. We report that central complement C3 protein and mRNA, classical complement C1q protein and mRNA, and microglia/monocyte phagocytic complement receptor CR3 all increase in response to ONI, especially within the optic nerve itself. Importantly, genetic deletion of C1q, C3, or CR3 attenuates RGC axon regeneration induced by several distinct methods, with minimal effects on RGC survival. Local injections of C1q function-blocking antibody revealed that complement acts primarily within the optic nerve, not retina, to support regeneration. Moreover, C1q opsonizes and CR3+ microglia/monocytes phagocytose growth-inhibitory myelin debris after ONI, a likely mechanism through which complement and myeloid cells support axon regeneration. Collectively, these results indicate that local optic nerve complement-myeloid phagocytic signaling is required for CNS axon regrowth, emphasizing the axonal compartment and highlighting a beneficial neuroimmune role for complement and microglia/monocytes in CNS repair.SIGNIFICANCE STATEMENT Despite the importance of achieving axon regeneration after CNS injury and the inevitability of inflammation after such injury, the contributions of complement and microglia to CNS axon regeneration are largely unknown. Whereas inflammation is commonly thought to exacerbate the effects of CNS injury, we find that complement proteins C1q and C3 and microglia/monocyte phagocytic complement receptor CR3 are each required for retinal ganglion cell axon regeneration through the injured mouse optic nerve. Also, whereas studies of optic nerve regeneration generally focus on the retina, we show that the regeneration-relevant role of complement and microglia/monocytes likely involves myelin phagocytosis within the optic nerve. Thus, our results point to the importance of the innate immune response for CNS repair.
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Affiliation(s)
- Sheri L Peterson
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
- F.M. Kirby Neurobiology Center, and
- Department of Neurosurgery and
| | - Yiqing Li
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
- F.M. Kirby Neurobiology Center, and
- Department of Neurosurgery and
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong China, 510060
| | - Christina J Sun
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
| | - Kimberly A Wong
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
- F.M. Kirby Neurobiology Center, and
- Department of Neurosurgery and
| | - Kylie S Leung
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
| | - Silmara de Lima
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
- F.M. Kirby Neurobiology Center, and
- Department of Neurosurgery and
| | - Nicholas J Hanovice
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
- F.M. Kirby Neurobiology Center, and
- Department of Neurosurgery and
| | - Kenya Yuki
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
- F.M. Kirby Neurobiology Center, and
- Department of Neurosurgery and
| | - Beth Stevens
- F.M. Kirby Neurobiology Center, and
- Howard Hughes Medical Institute, Boston Children's Hospital, Boston, Massachusetts 02115
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts 02142
| | - Larry I Benowitz
- Laboratories for Neuroscience Research in Neurosurgery
- Department of Neurosurgery
- F.M. Kirby Neurobiology Center, and
- Department of Neurosurgery and
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts 02115
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44
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A review of emerging neuroprotective and neuroregenerative therapies in traumatic spinal cord injury. Curr Opin Pharmacol 2021; 60:331-340. [PMID: 34520943 DOI: 10.1016/j.coph.2021.08.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 08/04/2021] [Indexed: 11/20/2022]
Abstract
Traumatic spinal cord injuries (SCIs) have far-reaching physical, social, and financial consequences. While medical advancements have improved supportive therapeutic measures for SCI patients, no effective neuroregenerative therapeutic options exist to date. Instead, the paradigm of SCI therapy is inevitably directed towards damage control rather than the restoration of a state of functional independence. Facing a continuous increase in the prevalence of spinal cord injured patients, neuroprotective and neuroregenerative strategies have earned tremendous scientific interest. This review intends to provide a robust summary of the most promising neuroprotective and neuroregenerative therapies currently under investigation. While we highlight encouraging neuroprotective strategies as well, the focus of this review lies on neuroregenerative therapies, including neuropharmacological and cell-based approaches. We finally point to the exciting investigational areas of biomaterial scaffolds and neuromodulation therapies.
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45
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Fague L, Liu YA, Marsh-Armstrong N. The basic science of optic nerve regeneration. ANNALS OF TRANSLATIONAL MEDICINE 2021; 9:1276. [PMID: 34532413 PMCID: PMC8421956 DOI: 10.21037/atm-20-5351] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 01/15/2021] [Indexed: 12/25/2022]
Abstract
Diverse insults to the optic nerve result in partial to total vision loss as the axons of retinal ganglion cells are destroyed. In glaucoma, axons are injured at the optic nerve head; in other optic neuropathies, axons can be damaged along the entire visual pathway. In all cases, as mammals cannot regenerate injured central nervous system cells, once the axons are lost, vision loss is irreversible. However, much has been learned about how retinal ganglion cells respond to axon injuries, and many of these crucial discoveries offer hope for future regenerative therapies. Here we review the current understanding regarding the temporal progression of axonal degeneration. We summarize known survival and regenerative mechanisms in mammals, including specific signaling pathways, key transcription factors, and reprogramming genes. We cover mechanisms intrinsic to retinal ganglion cells as well as their interactions with myeloid and glial cell populations in the retina and optic nerve that affect survival and regeneration. Finally, we highlight some non-mammalian species that are able to regenerate their retinal ganglion cell axons after injury, as understanding these successful regenerative responses may be essential to the rational design of future clinical interventions to regrow the optic nerve. In the end, a combination of many different molecular and cellular interventions will likely be the only way to achieve functional recovery of vision and restore quality of life to millions of patients around the world.
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Affiliation(s)
- Lindsay Fague
- UC Davis Eye Center, Department of Ophthalmology & Vision Science, University of California, Davis, Sacramento, CA, USA
| | - Yin Allison Liu
- UC Davis Eye Center, Department of Ophthalmology & Vision Science, University of California, Davis, Sacramento, CA, USA
| | - Nicholas Marsh-Armstrong
- UC Davis Eye Center, Department of Ophthalmology & Vision Science, University of California, Davis, Sacramento, CA, USA
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46
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Aspinall P, Harrison L, Scheuren P, Cragg JJ, Ferguson AR, Guest JD, Hsieh J, Jones L, Kirshblum S, Lammertse D, Kwon BK, Kramer JLK. A Systematic Review of Safety Reporting in Acute Spinal Cord Injury Clinical Trials: Challenges and Recommendations. J Neurotrauma 2021; 38:2047-2054. [PMID: 33899507 DOI: 10.1089/neu.2020.7540] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Accurate safety information in published clinical trials guides the assessment of risk-benefit, as well as the design of future clinical trials. Comprehensive reporting of adverse events, toxicity, and discontinuations from acute spinal cord injury clinical trials is an essential step in this process. Here, we sought to assess the degree of "satisfactoriness" of reporting in past clinical trials in spinal cord injury. A review of citations from MEDLINE and EMBASE identified eligible clinical trials in acute (within 30 days) spinal cord injury. English language studies, published between 1980 and 2020, with sensory, motor, or autonomic neurological assessments as the primary outcome measure were eligible for inclusion. Criteria were then established to qualify the safety reporting as satisfactory (i.e., distinguished severe/life-threatening events), partially satisfactory, or unsatisfactory (i.e., only mentioned in general statements, or reported but without distinguishing severe events). A total of 40 trials were included. Satisfactory reporting for clinical adverse events was observed in 30% of trials; partially satisfactory was achieved by 10% of the trials, and the remaining 60% were unsatisfactory. The majority of trials were determined to be unsatisfactory for the reporting of laboratory-defined toxicity (82.5%); only 17.5% were satisfactory. Discontinuations were satisfactorily reported for the majority of trials (80%), with the remaining partially satisfactory (5%) or unsatisfactory (15%). Reporting of safety in clinical trials for acute spinal cord injury is suboptimal. Due to the complexities of acute spinal cord injury (e.g., polytrauma, multiple systems affected), tailored and specific standards for tracking adverse events and safety reporting should be established.
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Affiliation(s)
- Paul Aspinall
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
| | - Liam Harrison
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
| | - Paulina Scheuren
- Spinal Cord Injury Center, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Jacquelyn J Cragg
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
- Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Adam R Ferguson
- Data Science, Brain and Spinal Injury Center, Department of Neurological Surgery, Weill Institute for Neurosciences, University of California San Francisco, San Francisco, California, USA
- San Francisco Veteran's Affairs Healthcare System, San Francisco, California, USA
| | - James D Guest
- Department of Neurological Surgery, University of Miami and the Miami Project to Cure Paralysis, Miami, Florida, USA
| | | | - Linda Jones
- Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Steven Kirshblum
- Department of Physical Medicine and Rehabilitation, Rutgers New Jersey Medical School, Newark, New Jersey, USA
- Kessler Institute for Rehabilitation, West Orange, New Jersey, USA
| | | | - Brian K Kwon
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
| | - John L K Kramer
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
- Department of Anesthesiology, Pharmacology, and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada
- Djavad Mowafaghian Center for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada
- Hugill Center for Anesthesiology, University of British Columbia, Vancouver, British Columbia, Canada
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47
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Guérout N. Plasticity of the Injured Spinal Cord. Cells 2021; 10:cells10081886. [PMID: 34440655 PMCID: PMC8395000 DOI: 10.3390/cells10081886] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 07/21/2021] [Accepted: 07/23/2021] [Indexed: 12/11/2022] Open
Abstract
Complete spinal cord injury (SCI) leads to permanent motor, sensitive and sensory deficits. In humans, there is currently no therapy to promote recovery and the only available treatments include surgical intervention to prevent further damage and symptomatic relief of pain and infections in the acute and chronic phases, respectively. Basically, the spinal cord is classically viewed as a nonregenerative tissue with limited plasticity. Thereby the establishment of the “glial” scar which appears within the SCI is mainly described as a hermetic barrier for axon regeneration. However, recent discoveries have shed new light on the intrinsic functional plasticity and endogenous recovery potential of the spinal cord. In this review, we will address the different aspects that the spinal cord plasticity can take on. Indeed, different experimental paradigms have demonstrated that axonal regrowth can occur even after complete SCI. Moreover, recent articles have demonstrated too that the “glial” scar is in fact composed of several cellular populations and that each of them exerts specific roles after SCI. These recent discoveries underline the underestimation of the plasticity of the spinal cord at cellular and molecular levels. Finally, we will address the modulation of this endogenous spinal cord plasticity and the perspectives of future therapeutic opportunities which can be offered by modulating the injured spinal cord microenvironment.
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Affiliation(s)
- Nicolas Guérout
- EA3830 GRHV, Institute for Research and Innovation in Biomedicine (IRIB), Normandie Université, UNIROUEN, 76000 Rouen, France
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48
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Naseri Kouzehgarani G, Feldsien T, Engelhard HH, Mirakhur KK, Phipps C, Nimmrich V, Clausznitzer D, Lefebvre DR. Harnessing cerebrospinal fluid circulation for drug delivery to brain tissues. Adv Drug Deliv Rev 2021; 173:20-59. [PMID: 33705875 DOI: 10.1016/j.addr.2021.03.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 02/10/2021] [Accepted: 03/01/2021] [Indexed: 12/31/2022]
Abstract
Initially thought to be useful only to reach tissues in the immediate vicinity of the CSF circulatory system, CSF circulation is now increasingly viewed as a viable pathway to deliver certain therapeutics deeper into brain tissues. There is emerging evidence that this goal is achievable in the case of large therapeutic proteins, provided conditions are met that are described herein. We show how fluid dynamic modeling helps predict infusion rate and duration to overcome high CSF turnover. We posit that despite model limitations and controversies, fluid dynamic models, pharmacokinetic models, preclinical testing, and a qualitative understanding of the glymphatic system circulation can be used to estimate drug penetration in brain tissues. Lastly, in addition to highlighting landmark scientific and medical literature, we provide practical advice on formulation development, device selection, and pharmacokinetic modeling. Our review of clinical studies suggests a growing interest for intra-CSF delivery, particularly for targeted proteins.
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49
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Jacobson PB, Goody R, Lawrence M, Mueller BK, Zhang X, Hooker BA, Pfleeger K, Ziemann A, Locke C, Barraud Q, Droescher M, Bernhard J, Popp A, Boeser P, Huang L, Mollon J, Mordashova Y, Cui YF, Savaryn JP, Grinnell C, Dreher I, Gold M, Courtine G, Mothe A, Tator CH, Guest JD. Elezanumab, a human anti-RGMa monoclonal antibody, promotes neuroprotection, neuroplasticity, and neurorecovery following a thoracic hemicompression spinal cord injury in non-human primates. Neurobiol Dis 2021; 155:105385. [PMID: 33991647 DOI: 10.1016/j.nbd.2021.105385] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 03/10/2021] [Accepted: 04/30/2021] [Indexed: 01/21/2023] Open
Abstract
Spinal cord injury (SCI) is a devastating condition characterized by loss of function, secondary to damaged spinal neurons, disrupted axonal connections, and myelin loss. Spontaneous recovery is limited, and there are no approved pharmaceutical treatments to reduce ongoing damage or promote repair. Repulsive guidance molecule A (RGMa) is upregulated following injury to the central nervous system (CNS), where it is believed to induce neuronal apoptosis and inhibit axonal growth and remyelination. We evaluated elezanumab, a human anti-RGMa monoclonal antibody, in a novel, newly characterized non-human primate (NHP) hemicompression model of thoracic SCI. Systemic intravenous (IV) administration of elezanumab over 6 months was well tolerated and associated with significant improvements in locomotor function. Treatment of animals for 16 weeks with a continuous intrathecal infusion of elezanumab below the lesion was not efficacious. IV elezanumab improved microstructural integrity of extralesional tissue as reflected by higher fractional anisotropy and magnetization transfer ratios in treated vs. untreated animals. IV elezanumab also reduced SCI-induced increases in soluble RGMa in cerebrospinal fluid, and membrane bound RGMa rostral and caudal to the lesion. Anterograde tracing of the corticospinal tract (CST) from the contralesional motor cortex following 20 weeks of IV elezanumab revealed a significant increase in the density of CST fibers emerging from the ipsilesional CST into the medial/ventral gray matter. There was a significant sprouting of serotonergic (5-HT) fibers rostral to the injury and in the ventral horn of lower thoracic regions. These data demonstrate that 6 months of intermittent IV administration of elezanumab, beginning within 24 h after a thoracic SCI, promotes neuroprotection and neuroplasticity of key descending pathways involved in locomotion. These findings emphasize the mechanisms leading to improved recovery of neuromotor functions with elezanumab in acute SCI in NHPs.
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Affiliation(s)
- Peer B Jacobson
- Department of Translational Sciences, Imaging Research, AbbVie Inc., 1 North Waukegan Rd., North Chicago, IL 60064, United States of America.
| | - Robin Goody
- Virscio, New Haven, CT, United States of America
| | | | - Bernhard K Mueller
- Discovery Biology, AbbVie Deutschland GmbH & Co. KG, Neuroscience Research, Knollstrasse, 67061 Ludwigshafen, Germany
| | - Xiaomeng Zhang
- Department of Translational Sciences, Imaging Research, AbbVie Inc., 1 North Waukegan Rd., North Chicago, IL 60064, United States of America
| | - Bradley A Hooker
- Department of Translational Sciences, Imaging Research, AbbVie Inc., 1 North Waukegan Rd., North Chicago, IL 60064, United States of America
| | - Kimberly Pfleeger
- Department of Neuroscience Development, AbbVie Inc., 1 North Waukegan Rd., North Chicago, IL 60064, United States of America
| | - Adam Ziemann
- Department of Neuroscience Development, AbbVie Inc., 1 North Waukegan Rd., North Chicago, IL 60064, United States of America
| | - Charles Locke
- Department of Biometrics, AbbVie Inc., 1 North Waukegan Rd., North Chicago, IL 60064, United States of America
| | - Quentin Barraud
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Geneva, Switzerland; Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland; Defitech Center for Interventional Neurotherapies, (NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Mathias Droescher
- Discovery Biology, AbbVie Deutschland GmbH & Co. KG, Neuroscience Research, Knollstrasse, 67061 Ludwigshafen, Germany
| | - Joerg Bernhard
- Discovery Biology, AbbVie Deutschland GmbH & Co. KG, Neuroscience Research, Knollstrasse, 67061 Ludwigshafen, Germany
| | - Andreas Popp
- Department of Preclinical Safety, AbbVie Deutschland GmbH & Co. KG, Neuroscience Research, Knollstrasse, 67061 Ludwigshafen, Germany
| | - Preethne Boeser
- Department of Preclinical Safety, AbbVie Deutschland GmbH & Co. KG, Neuroscience Research, Knollstrasse, 67061 Ludwigshafen, Germany
| | - Lili Huang
- AbbVie Biologics, AbbVie Bioresearch Center, 381 Plantation St., Worcester, MA 01605, United States of America
| | - Jennifer Mollon
- Data and Statistical Sciences, AbbVie Deutschland GmbH & Co. KG, Neuroscience Research, Knollstrasse, 67061 Ludwigshafen, Germany
| | - Yulia Mordashova
- Data and Statistical Sciences, AbbVie Deutschland GmbH & Co. KG, Neuroscience Research, Knollstrasse, 67061 Ludwigshafen, Germany
| | - Yi-Fang Cui
- Discovery Biology, AbbVie Deutschland GmbH & Co. KG, Neuroscience Research, Knollstrasse, 67061 Ludwigshafen, Germany
| | - John P Savaryn
- Department of Drug Metabolism and Pharmacokinetics, AbbVie Inc., 1 North Waukegan Rd., North Chicago, IL 60064, United States of America
| | - Christine Grinnell
- Department of Drug Metabolism and Pharmacokinetics, AbbVie Inc., 1 North Waukegan Rd., North Chicago, IL 60064, United States of America
| | - Ingeborg Dreher
- Department of Bioanalytics, AbbVie Deutschland GmbH & Co. KG, Neuroscience Research, Knollstrasse, 67061 Ludwigshafen, Germany
| | - Michael Gold
- Department of Neuroscience Development, AbbVie Inc., 1 North Waukegan Rd., North Chicago, IL 60064, United States of America
| | - Grégoire Courtine
- Center for Neuroprosthetics and Brain Mind Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Geneva, Switzerland; Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland; Defitech Center for Interventional Neurotherapies, (NeuroRestore), CHUV/UNIL/EPFL, Lausanne, Switzerland
| | - Andrea Mothe
- Krembil Brain Institute, Toronto Western Hospital, University Health Network, Toronto, Canada
| | - Charles H Tator
- Division of Neurosurgery, Toronto Western Hospital, and University of Toronto, Toronto, Canada
| | - James D Guest
- Department of Neurosurgery and The Miami Project to Cure Paralysis, The Miller School of Medicine, University of Miami, Miami, FL, United States of America
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50
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Delarue Q, Robac A, Massardier R, Marie JP, Guérout N. Comparison of the effects of two therapeutic strategies based on olfactory ensheathing cell transplantation and repetitive magnetic stimulation after spinal cord injury in female mice. J Neurosci Res 2021; 99:1835-1849. [PMID: 33960512 PMCID: PMC8359979 DOI: 10.1002/jnr.24836] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 03/08/2021] [Accepted: 03/12/2021] [Indexed: 12/11/2022]
Abstract
Spinal cord injury (SCI) is a debilitating condition, which leads to a permanent loss of functions below the injury site. The events which take place after SCI are characterized by cellular death, release of inhibitory factors, and inflammation. Many therapies have been studied to cure SCI, among them magnetic stimulation aims to reduce the secondary damages in particular by decreasing apoptosis, while, cellular transplantation promotes neuroregeneration by enhancing axonal regrowth. In the present study, we compared individually primary olfactory ensheathing cell (OEC) transplantation and repetitive trans‐spinal magnetic stimulation (rTSMS) and then, we combined these two therapeutic approaches on tissue repair and functional recovery after SCI. To do so, SCIs were performed at Th10 level on female C57BL/6 mice, which were randomized into four groups: SCI, SCI + primary bOECs, SCI + STM, SCI + primary bulbar olfactory ensheathing cells (bOECs) + stimulation (STM). On these animals bioluminescence, immunohistological, and behavioral experiments were performed after SCI. Our results show that rTSMS has beneficial effect on the modulation of spinal scar by reducing fibrosis, demyelination, and microglial cell activation and by increasing the astroglial component of the scar, while, primary bOEC transplantation decreases microglial reactivity. At the opposite, locotronic experiments show that both treatments induce functional recovery. We did not observed any additional effect by combining the two therapeutic approaches. Taken together, the present study indicates that primary bOEC transplantation and rTSMS treatment act through different mechanisms after SCI to induce functional recovery. In our experimental paradigm, the combination of the two therapies does not induce any additional benefit.
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Key Words
- RRID:AB_10563302: PDGFRβ, Abcam, ab91066
- RRID:AB_10643424: PE, poly4064, BioLegend, 406408
- RRID:AB_2313568: Jackson ImmunoResearch, 711-166-152
- RRID:AB_2340667: Jackson ImmunoResearch, 712-165-153
- RRID:AB_2340812: Jackson ImmunoResearch, 715-165-140
- RRID:AB_2715913: Alexa 488, MRG2b-85, BioLegend
- RRID:AB_306827: p75, Abcam, ab8874
- RRID:AB_476889: GFAP Cy3-conjugated Sigma-Aldrich, C9205
- RRID:AB_777165:P DGFRβAbcam ab32570
- RRID:AB_839504: Iba1, Wako, 019-19741
- RRID:AB_94975: MBP, Millipore, MAB386
- RRID:IMSR_JAX:008450: L2G85Chco+/+ (FVB-Tg(CAG-luc,-GFP)L2G85Chco/J)
- glial scar
- magnetic stimulation
- olfactory ensheathing cells and neuroregeneration
- rehabilitation
- spinal cord injury
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Affiliation(s)
- Quentin Delarue
- Normandie Univ, UNIROUEN, EA3830-GRHV, Rouen, France.,Institute for Research and Innovation in Biomedicine (IRIB), Rouen, France
| | - Amandine Robac
- Normandie Univ, UNIROUEN, EA3830-GRHV, Rouen, France.,Institute for Research and Innovation in Biomedicine (IRIB), Rouen, France
| | - Romane Massardier
- Normandie Univ, UNIROUEN, EA3830-GRHV, Rouen, France.,Institute for Research and Innovation in Biomedicine (IRIB), Rouen, France
| | - Jean-Paul Marie
- Normandie Univ, UNIROUEN, EA3830-GRHV, Rouen, France.,Institute for Research and Innovation in Biomedicine (IRIB), Rouen, France
| | - Nicolas Guérout
- Normandie Univ, UNIROUEN, EA3830-GRHV, Rouen, France.,Institute for Research and Innovation in Biomedicine (IRIB), Rouen, France
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