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Shen T, Zhang W, Wang X, Ren X. Application of"Spinal cord fusion" in spinal cord injury repair and its neurological mechanism. Heliyon 2024; 10:e29422. [PMID: 38638967 PMCID: PMC11024622 DOI: 10.1016/j.heliyon.2024.e29422] [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] [Received: 04/06/2023] [Revised: 04/03/2024] [Accepted: 04/08/2024] [Indexed: 04/20/2024] Open
Abstract
Spinal cord injury (SCI) is a severely disabling and catastrophic condition that poses significant global clinical challenges. The difficulty of SCI repair results from the distinctive pathophysiological mechanisms, which are characterised by limited regenerative capacity and inadequate neuroplasticity of the spinal cord. Additionally, the formation of cystic cavities and astrocytic scars after SCI further obstructs both the ascending and descending neural conduction pathways. Consequently, the urgent challenge in post-SCI recovery lies in repairing the damaged spinal cord to reconstruct a functional and intact neural conduction circuit. In recent years, significant advancements in biological tissue engineering technology and novel therapies have resulted in a transformative shift in the field of SCI repair. Currently, SCI treatment primarily involves drug therapy, stem cell therapy, the use of biological materials, growth factors, and other approaches. This paper comprehensively reviews the progress in SCI research over the years, with a particular focus on the concept of "Spinal Cord Fusion" as a promising technique for SCI reconstruction. By discussing this important research progress and the neurological mechanisms involved, our aim is to help solve the problem of SCI repair as soon as possible and to bring new breakthroughs in the treatment of paraplegia after SCI.
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Affiliation(s)
- Tingting Shen
- Guangxi University of Chinese Medicine, Nanning, Guangxi, 530001, China
- Department of Orthopedics, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, 530011, China
- Institute of Orthopedics, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, 530011, China
- Global Initiative to Cure Paralysis (GICUP Alliance), Columbus, OH, 43221, United States
| | - Weihua Zhang
- Department of Orthopedics, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, 530011, China
- Institute of Orthopedics, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, 530011, China
- Global Initiative to Cure Paralysis (GICUP Alliance), Columbus, OH, 43221, United States
| | - Xiaogang Wang
- Guangxi University of Chinese Medicine, Nanning, Guangxi, 530001, China
- Department of Orthopedics, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, 530011, China
- Institute of Orthopedics, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, 530011, China
- Global Initiative to Cure Paralysis (GICUP Alliance), Columbus, OH, 43221, United States
| | - Xiaoping Ren
- Department of Orthopedics, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, 530011, China
- Institute of Orthopedics, Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, Nanning, Guangxi, 530011, China
- Global Initiative to Cure Paralysis (GICUP Alliance), Columbus, OH, 43221, United States
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Yang Y, Zhang L, Huang M, Sui R, Khan S. Reconstruction of the cervical spinal cord based on motor function restoration and mitigation of oxidative stress and inflammation through eNOS/Nrf2 signaling pathway using ibuprofen-loaded nanomicelles. ARAB J CHEM 2021. [DOI: 10.1016/j.arabjc.2021.103289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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3
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Li JJ, Liu H, Zhu Y, Yan L, Liu R, Wang G, Wang B, Zhao B. Animal Models for Treating Spinal Cord Injury Using Biomaterials-Based Tissue Engineering Strategies. TISSUE ENGINEERING PART B-REVIEWS 2021; 28:79-100. [PMID: 33267667 DOI: 10.1089/ten.teb.2020.0267] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Jiao Jiao Li
- School of Biomedical Engineering, Faculty of Engineering and IT, University of Technology Sydney, Ultimo, Australia
| | - Haifeng Liu
- Department of Orthopedics and Shanxi Medical University Second Affiliated Hospital, Taiyuan, China
| | - Yuanyuan Zhu
- Department of Pharmacy, Shanxi Medical University Second Affiliated Hospital, Taiyuan, China
| | - Lei Yan
- Department of Orthopedics and Shanxi Medical University Second Affiliated Hospital, Taiyuan, China
| | - Ruxing Liu
- Department of Orthopedics and Shanxi Medical University Second Affiliated Hospital, Taiyuan, China
| | - Guishan Wang
- Department of Biochemistry and Molecular Biology, Shanxi Medical University, Taiyuan, China
| | - Bin Wang
- Department of Orthopedics and Shanxi Medical University Second Affiliated Hospital, Taiyuan, China
- Department of Sports Medicine and Adult Reconstruction Surgery, Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Bin Zhao
- Department of Orthopedics and Shanxi Medical University Second Affiliated Hospital, Taiyuan, China
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Ren S, Liu Z, Kim CY, Fu K, Wu Q, Hou L, Sun L, Zhang J, Miao Q, Kim J, Bonicalzi V, Guan X, Zhang M, Zhang W, Xu J, Canavero S, Ren X. Reconstruction of the spinal cord of spinal transected dogs with polyethylene glycol. Surg Neurol Int 2019; 10:50. [PMID: 31528388 PMCID: PMC6743687 DOI: 10.25259/sni-73-2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 01/02/2019] [Indexed: 12/14/2022] Open
Abstract
Background: Our study shows that a membrane sealant/fiber fusogen polyethylene glycol (PEG) applied immediately on a sharp section of the spinal cord can mend the cord and lead to exceptional levels of motor recovery, with some animals almost normal. Materials and Methods: Before deploying such technology in man, long-term data in large mammals that exclude delayed complications (e.g., central pain), confirm the stability of motor recovery, and provide histological evidence of fiber regrowth are necessary. Here, we provide such evidence in dogs followed up over 6 months and in 2 cases up to 1 year along with imaging and histologic data. Results: We show that dogs whose dorsal cord has been fully transected recover locomotion after immediate treatment with a fusogen (PEG). No pain syndrome ensued over the long term. Diffusion tensor imaging magnetic resonance and histological, including immunohistochemical, data confirmed the re-establishment of anatomical continuity along with interfacial axonal sprouting. Conclusions: This study proves that a form of irreversible spinal cord injury (SCI) can effectively be treated and points out a way to treat SCI patients.
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Affiliation(s)
- Shuai Ren
- Hand and Microsurgery Center, The Second Affiliated Hospital of Harbin Medical University, Nangang, Harbin 150081, China
| | - Zehan Liu
- Hand and Microsurgery Center, The Second Affiliated Hospital of Harbin Medical University, Nangang, Harbin 150081, China
| | - C Yoon Kim
- Department of Stem Cell Biology, School of Medicine, Konkuk University, Seoul 10100, Korea
| | - Kuang Fu
- Department of MR Diagnosis, The Second Affiliated Hospital of Harbin Medical University, Nangang, Harbin 150081, China
| | - Qiong Wu
- Department of MR Diagnosis, The Second Affiliated Hospital of Harbin Medical University, Nangang, Harbin 150081, China
| | - Liting Hou
- Department of Anesthesia, The Second Affiliated Hospital of Harbin Medical University, Nangang, Harbin 150081, China
| | - Linlin Sun
- Department of Pharmacology, Harbin Medical University, Nangang, Harbin 150081, China
| | - Jian Zhang
- Hand and Microsurgery Center, The Second Affiliated Hospital of Harbin Medical University, Nangang, Harbin 150081, China
| | - Qing Miao
- Hand and Microsurgery Center, The Second Affiliated Hospital of Harbin Medical University, Nangang, Harbin 150081, China
| | - Jin Kim
- Department of Laboratory Animal Medicine, College of Veterinary Medicine, Seoul National University, Seoul 10100, Korea
| | - Vincenzo Bonicalzi
- Department of Neurology, The Second Affiliated Hospital of Harbin Medical University, Nangang, Harbin 150081, China
| | - Xiangchen Guan
- Hand and Microsurgery Center, The Second Affiliated Hospital of Harbin Medical University, Nangang, Harbin 150081, China
| | - Mingzhe Zhang
- Hand and Microsurgery Center, The Second Affiliated Hospital of Harbin Medical University, Nangang, Harbin 150081, China
| | - Weihua Zhang
- Hand and Microsurgery Center, The Second Affiliated Hospital of Harbin Medical University, Nangang, Harbin 150081, China
| | - Junfeng Xu
- Hand and Microsurgery Center, The Second Affiliated Hospital of Harbin Medical University, Nangang, Harbin 150081, China
| | - Sergio Canavero
- Department of Neurology, The Second Affiliated Hospital of Harbin Medical University, Nangang, Harbin 150081, China
| | - Xiaoping Ren
- Hand and Microsurgery Center, The Second Affiliated Hospital of Harbin Medical University, Nangang, Harbin 150081, China
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Ren X, Kim CY, Canavero S. Bridging the gap: Spinal cord fusion as a treatment of chronic spinal cord injury. Surg Neurol Int 2019; 10:51. [PMID: 31528389 PMCID: PMC6743693 DOI: 10.25259/sni-19-2019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 02/06/2019] [Indexed: 12/15/2022] Open
Abstract
Despite decades of animal experimentation, human translation with cell grafts, conduits, and other strategies has failed to cure patients with chronic spinal cord injury (SCI). Recent data show that motor deficits due to spinal cord transection in animal models can be reversed by local application of fusogens, such as Polyethylene glycol (PEG). Results proved superior at short term over all other treatments deployed in animal studies, opening the way to human trials. In particular, removal of the injured spinal cord segment followed by PEG fusion of the two ends along with vertebral osteotomy to shorten the spine holds the promise for a cure in many cases.
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Affiliation(s)
- Xiaoping Ren
- Hand and Microsurgery Center, Second Affiliated Hospital of Harbin Medical University, Nangang, Harbin, China
- State-Province Key Laboratories of Biomedicine-Pharmaceutics, Harbin Medical University, Nangang, Harbin, China
- Heilongjiang Medical Science Institute, Harbin Medical University, Nangang, Harbin, China
| | - C-Yoon Kim
- Department of Stem Cell Biology, School of Medicine, Konkuk University, Seoul, Korea
| | - Sergio Canavero
- HEAVEN-GEMINI International Collaborative Group, Turin, Italy
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Lu X, Perera TH, Aria AB, Callahan LAS. Polyethylene glycol in spinal cord injury repair: a critical review. J Exp Pharmacol 2018; 10:37-49. [PMID: 30100766 PMCID: PMC6067622 DOI: 10.2147/jep.s148944] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Polyethylene glycol (PEG) is a synthetic biocompatible polymer with many useful properties for developing therapeutics to treat spinal cord injury. Direct application of PEG as a fusogen to the injury site can repair cell membranes, mitigate oxidative stress, and promote axonal regeneration to restore motor function. PEG can be covalently or noncovalently conjugated to proteins, peptides, and nanoparticles to limit their clearance by the reticuloendothelial system, reduce their immunogenicity, and facilitate crossing the blood-brain barrier. Cross-linking PEG produces hydrogels that can act as delivery vehicles for bioactive molecules including growth factors and cells such as bone marrow stromal cells, which can modulate the inflammatory response and support neural tissue regeneration. PEG hydrogels can be cross-linked in vitro or delivered as an injectable formulation that can gel in situ at the site of injury. Chemical and mechanical properties of PEG hydrogels are tunable and must be optimized for creating the most favorable delivery environment. Peptides mimicking extracellular matrix protein such as laminin and n-cadherin can be incorporated into PEG hydrogels to promote neural differentiation and axonal extensions. Different hydrogel cross-linking densities and stiffness will also affect the differentiation process. PEG hydrogels with a gradient of peptide concentrations or Young's modulus have been developed to systematically study these factors. This review will describe these and other recent advancements of PEG in the field of spinal cord injury in greater detail.
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Affiliation(s)
- Xi Lu
- Department of Neurosurgery, Center for Stem Cells and Regenerative Medicine, University of Texas Health Science Center at Houston, Houston, TX, USA,
| | - T Hiran Perera
- Department of Neurosurgery, Center for Stem Cells and Regenerative Medicine, University of Texas Health Science Center at Houston, Houston, TX, USA,
| | - Alexander B Aria
- Department of Neurosurgery, Center for Stem Cells and Regenerative Medicine, University of Texas Health Science Center at Houston, Houston, TX, USA,
| | - Laura A Smith Callahan
- Department of Neurosurgery, Center for Stem Cells and Regenerative Medicine, University of Texas Health Science Center at Houston, Houston, TX, USA,
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Ausman JI. Is it time to perform the first human head transplant? Comment on the CSA (CephaloSomatic Ansatomisis) paper by Ren, Canavero, and colleagues. Surg Neurol Int 2018; 9:28. [PMID: 29492328 PMCID: PMC5820846 DOI: 10.4103/sni.sni_472_17] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 12/12/2017] [Indexed: 01/13/2023] Open
Affiliation(s)
- James I Ausman
- Emeritus Editor-in-Chief and Publisher, SNI Publications, Professor, Neurosurgery, David Geffen School of Medicine at UCLA, Los Angeles, CA and Harbor-UCLA Medical Center, Torrance, CA, USA
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Non-functionalized soft alginate hydrogel promotes locomotor recovery after spinal cord injury in a rat hemimyelonectomy model. Acta Neurochir (Wien) 2018; 160:449-457. [PMID: 29230560 DOI: 10.1007/s00701-017-3389-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 10/31/2017] [Indexed: 12/29/2022]
Abstract
BACKGROUND Spinal cord injury (SCI) and the consecutive devastating neurological sequelae have an enormous individual and economic impact. Implantation of functionalized hydrogels is a promising approach, because they can serve as a matrix for the regenerating tissue, carry and release bioactive molecules and various cell types. We already demonstrated that non-functionalized soft alginate hydrogel supported axonal outgrowth and protected neurons against oxidative stress in vitro. Here, we investigated the effects of such soft alginate hydrogels on locomotor recovery in small and large spinal cord lesions. METHOD Hemimyelonectomy of 2 mm or 4 mm length was performed in rats and soft alginate hydrogel was implanted. Functional recovery of the hindlimbs was assessed in the open field [Batto Beattie Bresnahan (BBB) score] and using swimming test [Louisville Swim score (LSS)] for 140 days post injury (DPI). Reference histology was performed. RESULTS Rats that received an alginate implant into 2 mm spinal cord lesions demonstrated significantly improved locomotor recovery compared to controls detectable already at 10 DPI. At 140 DPI, they reached higher LSS and BBB scores in swimming and open field tests, respectively. However, this beneficial effect of alginate was lacking in animals with larger (4 mm) lesions. Histological examination suggested that fibrous scarring in the spinal cord was reduced after alginate implantation in comparison to controls. CONCLUSIONS Implantation of soft alginate hydrogel in small spinal cord lesions improved functional recovery. Possible underlying mechanisms include the mechanical stabilization of the wound, reduction of secondary damage and inhibition of fibrous scarring.
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Kim CY, Sikkema WKA, Kim J, Kim JA, Walter J, Dieter R, Chung HM, Mana A, Tour JM, Canavero S. Effect of Graphene Nanoribbons (TexasPEG) on locomotor function recovery in a rat model of lumbar spinal cord transection. Neural Regen Res 2018; 13:1440-1446. [PMID: 30106057 PMCID: PMC6108198 DOI: 10.4103/1673-5374.235301] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
A sharply transected spinal cord has been shown to be fused under the accelerating influence of membrane fusogens such as polyethylene glycol (PEG) (GEMINI protocol). Previous work provided evidence that this is in fact possible. Other fusogens might improve current results. In this study, we aimed to assess the effects of PEGylated graphene nanoribons (PEG-GNR, and called “TexasPEG” when prepared as 1wt% dispersion in PEG600) versus placebo (saline) on locomotor function recovery and cellular level in a rat model of spinal cord transection at lumbar segment 1 (L1) level. In vivo and in vitro experiments (n = 10 per experiment) were designed. In the in vivo experiment, all rats were submitted to full spinal cord transection at L1 level. Five weeks later, behavioral assessment was performed using the Basso Beattie Bresnahan (BBB) locomotor rating scale. Immunohistochemical staining with neuron marker neurofilament 200 (NF200) antibody and astrocytic scar marker glial fibrillary acidic protein (GFAP) was also performed in the injured spinal cord. In the in vitro experiment, the effects of TexasPEG application for 72 hours on the neurite outgrowth of SH-SY5Y cells were observed under the inverted microscope. Results of both in vivo and in vitro experiments suggest that TexasPEG reduces the formation of glial scars, promotes the regeneration of neurites, and thereby contributes to the recovery of locomotor function of a rat model of spinal cord transfection.
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Affiliation(s)
- C-Yoon Kim
- Department of Stem Cell Biology, School of Medicine, Konkuk University; Department of Laboratory Animal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | - William K A Sikkema
- Department of Chemistry, Department of Materials Science and NanoEngineering, and The NanoCarbon Center, Rice University, Houston, TX, USA
| | - Jin Kim
- Department of Laboratory Animal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | - Jeong Ah Kim
- Biomedical Omics Group, Korea Basic Science Institute, Cheongju-si, Chungbuk, Korea
| | - James Walter
- Research Service, Hines Veterans Administration Hospital, Hines, IL, USA
| | - Raymond Dieter
- Research Service, Hines Veterans Administration Hospital, Hines, IL, USA
| | - Hyung-Min Chung
- Department of Stem Cell Biology, School of Medicine, Konkuk University, Seoul, Korea
| | - Andrea Mana
- HEAVEN/GEMINI International Collaborative Group, Turin, Italy
| | - James M Tour
- Department of Chemistry, Department of Materials Science and NanoEngineering, and The NanoCarbon Center, Rice University, Houston, TX, USA
| | - Sergio Canavero
- HEAVEN/GEMINI International Collaborative Group, Turin, Italy
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Restoration of motor function after operative reconstruction of the acutely transected spinal cord in the canine model. Surgery 2017; 163:976-983. [PMID: 29223327 DOI: 10.1016/j.surg.2017.10.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 09/20/2017] [Accepted: 10/11/2017] [Indexed: 11/22/2022]
Abstract
BACKGROUND Cephalosomatic anastomosis or what has been called a "head transplantation" requires full reconnection of the respective transected ends of the spinal cords. The GEMINI spinal cord fusion protocol has been developed for this reason. Here, we report the first randomized, controlled study of the GEMINI protocol in large animals. METHODS We conducted a randomized, controlled study of a complete transection of the spinal cord at the level of T10 in dogs at Harbin Medical University, Harbin, China. These dogs were followed for up to 8 weeks postoperatively by assessments of recovery of motor function, somato-sensory evoked potentials, and diffusion tensor imaging using magnetic resonance imaging. RESULTS A total of 12 dogs were subjected to operative exposure of the dorsal aspect of the spinal cord after laminectomy and longitudinal durotomy followed by a very sharp, controlled, full-thickness, complete transection of the spinal cord at T10. The fusogen, polyethylene glycol, was applied topically to the site of the spinal cord transection in 7 of 12 dogs; 0.9% NaCl saline was applied to the site of transection in the remaining 5 control dogs. Dogs were selected randomly to receive polyethylene glycol or saline. All polyethylene glycol-treated dogs reacquired a substantial amount of motor function versus none in controls over these first 2 months as assessed on the 20-point (0-19), canine, Basso-Beattie-Bresnahan rating scale (P<.006). Somatosensory evoked potentials confirmed restoration of electrical conduction cranially across the site of spinal cord transection which improved over time. Diffusion tensor imaging, a magnetic resonance permutation that assesses the integrity of nerve fibers and cells, showed restitution of the transected spinal cord with polyethylene glycol treatment (at-injury level difference: P<.02). CONCLUSION A sharply and fully transected spinal cord at the level of T10 can be reconstructed with restoration of many aspects of electrical continuity in large animals following the GEMINI spinal cord fusion protocol, with objective evidence of motor recovery and of electrical continuity across the site of transection, opening the way to the first cephalosomatic anastomosis. (Surgery 2017;160:XXX-XXX.).
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Sikkema WKA, Metzger AB, Wang T, Tour JM. Physical and electrical characterization of TexasPEG: An electrically conductive neuronal scaffold. Surg Neurol Int 2017; 8:84. [PMID: 28607818 PMCID: PMC5461561 DOI: 10.4103/sni.sni_361_16] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 02/16/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Graphene and its derivatives have been shown to be biocompatible and electrically active materials upon which neurons readily grow. The fusogen poly(ethylene glycol) (PEG) has been shown to improve outcomes after cervical and dorsal spinal cord transection. The long and narrow PEGylated graphene nanoribbon stacks (PEG-GNRs) with their 5 μm × 200 nm × 10 nm dimensions can provide a scaffold upon which neurons can grow and fuse. We disclose here the extensive characterization data for the PEG-GNRs. METHODS PEG-GNRs were chemically synthesized and chemically and electrically characterized. RESULTS The average aspect ratio of the PEG-GNRs was determined to be ~85, which corresponds to a critical percolation value (the point where insulating material becomes conductive by addition of conductive particles) of 1%. However, there was not a sharp increase in AC conductivity at frequencies relevant to action potentials. CONCLUSION A robust characterization of PEG-GNRs is discussed, though the precise origin of efficacy in improving outcomes following spinal cord transection is not known.
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Affiliation(s)
| | | | - Tuo Wang
- Department of Chemistry, Rice University, Houston, Texas, USA
| | - James M. Tour
- Department of Chemistry, Rice University, Houston, Texas, USA
- The NanoCarbon Center, Rice University, Houston, Texas, USA
- Department of Material Science and Nanoengineering, Rice University, Houston, Texas, USA
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13
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Kim CY, Oh H, Ren X, Canavero S. Immunohistochemical evidence of axonal regrowth across polyethylene glycol-fused cervical cords in mice. Neural Regen Res 2017; 12:149-150. [PMID: 28250761 PMCID: PMC5319221 DOI: 10.4103/1673-5374.199014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Affiliation(s)
- C-Yoon Kim
- Department of Stem Cell Biology, School of Medicine, Konkuk University, Seoul, Korea; Department of Laboratory Animal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, Korea; Heaven/Gemini International Collaborative Group, Turin, Italy
| | - Hanseul Oh
- Department of Laboratory Animal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, Korea; Heaven/Gemini International Collaborative Group, Turin, Italy
| | - Xiaoping Ren
- Hand and Microsurgical Center, the Second Affiliated Hospital of Harbin Medical University; State-Province Key Laboratories of Biomedicine-Pharmaceutics, Harbin Medical University, Harbin, Heilongjiang Province, China; Heaven/Gemini International Collaborative Group, Turin, Italy
| | - Sergio Canavero
- Turin Advanced Neuromodulation Group, Turin, Italy; Heaven/Gemini International Collaborative Group, Turin, Italy
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Canavero S, Ren X, Kim CY. HEAVEN: The Frankenstein effect. Surg Neurol Int 2016; 7:S623-5. [PMID: 27656323 PMCID: PMC5025952 DOI: 10.4103/2152-7806.190472] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 07/29/2016] [Indexed: 11/23/2022] Open
Abstract
The HEAVEN head transplant initiative needs human data concerning the acute restoration of motor transmission after application of fusogens to the severed cord in man. Data from two centuries ago prove that a fresh cadaver, after hanging or decapitation, can be mobilized by electrical stimulation for up to 3 hours. By administering spinal cord stimulation by applied paddles to the cord or transcranial magnetic stimulation to M1 and recording motor evoked potentials, it should be possible to test fusogens in fresh cadavers. Delayed neuronal death might be the neuropathological reason.
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Affiliation(s)
- Sergio Canavero
- HEAVEN/GEMINI International Collaborative Group, Turin, Italy
| | - XiaoPing Ren
- HEAVEN/GEMINI International Collaborative Group, Turin, Italy
| | - C Yoon Kim
- HEAVEN/GEMINI International Collaborative Group, Turin, Italy
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Canavero S, Ren X. Houston, GEMINI has landed: Spinal cord fusion achieved. Surg Neurol Int 2016; 7:S626-8. [PMID: 27656324 PMCID: PMC5025958 DOI: 10.4103/2152-7806.190473] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 09/01/2016] [Indexed: 11/23/2022] Open
Affiliation(s)
- Sergio Canavero
- HEAVEN/GEMINI International Collaborative Group, Turin, Italy
| | - Xiaoping Ren
- HEAVEN/GEMINI International Collaborative Group, Turin, Italy
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Kim CY, Oh H, Hwang IK, Hong KS. GEMINI: Initial behavioral results after full severance of the cervical spinal cord in mice. Surg Neurol Int 2016; 7:S629-31. [PMID: 27656325 PMCID: PMC5025949 DOI: 10.4103/2152-7806.190474] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Accepted: 08/31/2016] [Indexed: 11/16/2022] Open
Abstract
Background: The GEMINI spinal cord fusion protocol has been developed to achieve a successful cephalosomatic anastomosis. Here, we report the preliminary data on the use of a fusogen [polyethylene glycol (PEG)] after full cervical cord transection in mice to facilitate the fusion of both ends of a sharply transected spinal cord. Methods: Cervical laminectomy and a complete, visually confirmed cervical cord (C 5) transection was performed on female albino mice (n = 16). In Group 1 (n = 8), a fusogen, (PEG) was used to bridge the gap between the cut ends of the spinal cord. Group 2 received the same spinal cord transection but was treated with saline. Outcome was assessed daily using a standard scale (modified 22-point Basso-Beattie-Bresnahan scale) and filmed on camera. Results: The PEG group (group 1) showed partial restoration of motor function after 4 weeks of observation; group 2 (placebo) did not recover any useful motor activity. Conclusion: In this preliminary experiment, PEG, but not saline, promoted partial motor recovery in mice submitted to full cervical transection.
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Affiliation(s)
- C-Yoon Kim
- Department of Stem Cell Biology, School of Medicine, Konkuk University, Seoul, Korea; Department of Laboratory Animal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | - Hanseul Oh
- Department of Laboratory Animal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | - In-Kyu Hwang
- Department of Stem Cell Biology, School of Medicine, Konkuk University, Seoul, Korea
| | - Ki-Sung Hong
- Department of Stem Cell Biology, School of Medicine, Konkuk University, Seoul, Korea
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Kim CY, Sikkema WKA, Hwang IK, Oh H, Kim UJ, Lee BH, Tour JM. Spinal cord fusion with PEG-GNRs (TexasPEG): Neurophysiological recovery in 24 hours in rats. Surg Neurol Int 2016; 7:S632-6. [PMID: 27656326 PMCID: PMC5025948 DOI: 10.4103/2152-7806.190475] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Accepted: 08/31/2016] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND The GEMINI spinal cord fusion protocol has been developed to achieve a successful cephalosomatic anastomosis. Here, for the first time, we report the effects of locally applied water-soluble, conductive PEG(polyethylene glycol)ylated graphene nanoribbons (PEG-GNRs) on neurophysiologic conduction after sharp cervical cord transection in rats. PEG-GNRs were produced by the polymerization of ethylene oxide from anion-edged graphene nanoribbons. These combine the fusogenic potential of PEG with the electrical conducting properties of the graphene nanoribbons. METHODS Laminectomy and transection of cervical spinal cord (C5) was performed on Female Sprague-Dawley (SD) rats. After applying PEG-GNR on the severed part, electrophysiological recovery of the reconstructed cervical spinal cord was confirmed by somatosensory evoked potentials (SSEPs) at 24 h after surgery. RESULTS While no SSEPs were detected in the control group, PEG-GNR treated group showed fast recovery of SSEPs at 24 h after the surgery. CONCLUSION In this preliminary dataset, for the first time, we report the effect of a novel form of PEG with the goal of rapid reconstruction of a sharply severed spinal cord.
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Affiliation(s)
- C-Yoon Kim
- Department of Stem Cell Biology, School of Medicine, Konkuk University, Seoul, Korea
- Department of Laboratory Animal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | | | - In-Kyu Hwang
- Department of Stem Cell Biology, School of Medicine, Konkuk University, Seoul, Korea
| | - Hanseul Oh
- Department of Laboratory Animal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | - Un Jeng Kim
- Department of Physiology, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea
| | - Bae Hwan Lee
- Department of Physiology, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea
| | - James M. Tour
- Department of Chemistry, Rice University, Houston, Texas, USA
- The NanoCarbon Center, Rice University, Houston, Texas, USA
- Department of Material Science and Nanoengineering, Rice University, Houston, Texas, USA
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Kim CY, Hwang IK, Kim H, Jang SW, Kim HS, Lee WY. Accelerated recovery of sensorimotor function in a dog submitted to quasi-total transection of the cervical spinal cord and treated with PEG. Surg Neurol Int 2016; 7:S637-40. [PMID: 27656327 PMCID: PMC5026027 DOI: 10.4103/2152-7806.190476] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Accepted: 08/31/2016] [Indexed: 11/12/2022] Open
Abstract
Background: A case report on observing the recovery of sensory-motor function after cervical spinal cord transection. Case Description: Laminectomy and transection of cervical spinal cord (C5) was performed on a male beagle weighing 3.5 kg. After applying polyethylene glycol (PEG) on the severed part, reconstruction of cervical spinal cord was confirmed by the restoration of sensorimotor function. Tetraplegia was observed immediately after operation, however, the dog showed stable respiration and survival without any complication. The dog showed fast recovery after 1 week, and recovered approximately 90% of normal sensorimotor function 3 weeks after the operation, although urinary disorder was still present. All recovery stages were recorded by video camera twice a week for behavioral analysis. Conclusion: While current belief holds that functional recovery is impossible after a section greater than 50% at C5-6 in the canine model, this case study shows the possibility of cervical spinal cord reconstruction after near-total transection. Furthermore, this case study also confirms that PEG can truly expedite the recovery of sensorimotor function after cervical spinal cord sections in dogs.
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Affiliation(s)
- C-Yoon Kim
- Department of Stem Cell Biology, School of Medicine, Konkuk University, Seoul, Korea
| | - In-Kyu Hwang
- Department of Stem Cell Biology, School of Medicine, Konkuk University, Seoul, Korea
| | - Hana Kim
- Department of Stem Cell Biology, School of Medicine, Konkuk University, Seoul, Korea
| | | | | | - Won-Young Lee
- Department of Food Bioscience, College of Biomedical and Health Science, Konkuk University, Chung-ju, Korea
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Palejwala AH, Fridley JS, Mata JA, Samuel ELG, Luerssen TG, Perlaky L, Kent TA, Tour JM, Jea A. Biocompatibility of reduced graphene oxide nanoscaffolds following acute spinal cord injury in rats. Surg Neurol Int 2016; 7:75. [PMID: 27625885 PMCID: PMC5009578 DOI: 10.4103/2152-7806.188905] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 06/20/2016] [Indexed: 11/05/2022] Open
Abstract
Background: Graphene has unique electrical, physical, and chemical properties that may have great potential as a bioscaffold for neuronal regeneration after spinal cord injury. These nanoscaffolds have previously been shown to be biocompatible in vitro; in the present study, we wished to evaluate its biocompatibility in an in vivo spinal cord injury model. Methods: Graphene nanoscaffolds were prepared by the mild chemical reduction of graphene oxide. Twenty Wistar rats (19 male and 1 female) underwent hemispinal cord transection at approximately the T2 level. To bridge the lesion, graphene nanoscaffolds with a hydrogel were implanted immediately after spinal cord transection. Control animals were treated with hydrogel matrix alone. Histologic evaluation was performed 3 months after the spinal cord transection to assess in vivo biocompatibility of graphene and to measure the ingrowth of tissue elements adjacent to the graphene nanoscaffold. Results: The graphene nanoscaffolds adhered well to the spinal cord tissue. There was no area of pseudocyst around the scaffolds suggestive of cytotoxicity. Instead, histological evaluation showed an ingrowth of connective tissue elements, blood vessels, neurofilaments, and Schwann cells around the graphene nanoscaffolds. Conclusions: Graphene is a nanomaterial that is biocompatible with neurons and may have significant biomedical application. It may provide a scaffold for the ingrowth of regenerating axons after spinal cord injury.
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Affiliation(s)
- Ali H Palejwala
- Department of Neurosurgery, Baylor College of Medicine, Houston, Texas, USA; Division of Pediatric Neurosurgery, Texas Children's Hospital, Houston, Texas, USA
| | - Jared S Fridley
- Department of Neurosurgery, Baylor College of Medicine, Houston, Texas, USA; Division of Pediatric Neurosurgery, Texas Children's Hospital, Houston, Texas, USA
| | - Javier A Mata
- Department of Neurosurgery, Baylor College of Medicine, Houston, Texas, USA; Division of Pediatric Neurosurgery, Texas Children's Hospital, Houston, Texas, USA
| | | | - Thomas G Luerssen
- Department of Neurosurgery, Baylor College of Medicine, Houston, Texas, USA; Division of Pediatric Neurosurgery, Texas Children's Hospital, Houston, Texas, USA
| | - Laszlo Perlaky
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA; Research and Tissue Support Services Core Laboratory, Texas Children's Cancer and Hematology Services, Houston, Texas, USA
| | - Thomas A Kent
- Department of Neurology, Baylor College of Medicine, Houston, Texas, USA; Interdepartmental Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, Texas, USA; Center for Translational Research in Inflammatory Diseases, Michael E. DeBakey VA Medical Center, Houston, Texas, USA
| | - James M Tour
- Department of Chemistry, Rice University, Houston, Texas, USA; Department of Chemistry and Materials Science and NanoEngineering, Rice University, Houston, Texas, USA
| | - Andrew Jea
- Department of Neurosurgery, Baylor College of Medicine, Houston, Texas, USA; Division of Pediatric Neurosurgery, Texas Children's Hospital, Houston, Texas, USA
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Ye Y, Kim CY, Miao Q, Ren X. Fusogen-assisted rapid reconstitution of anatomophysiologic continuity of the transected spinal cord. Surgery 2016; 160:20-25. [PMID: 27138179 DOI: 10.1016/j.surg.2016.03.023] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 02/04/2016] [Accepted: 03/25/2016] [Indexed: 11/26/2022]
Abstract
The GEMINI spinal cord fusion protocol exploits the ability of so-called fusogens, such as polyethylene glycol (PEG), to achieve rapid neural restoration of electrical continuity across the ends of a transected spinal cord. Experimental evidence suggests that motor recovery can occur after complete transection of the cervical and dorsal spinal cord in mice and rats following application of PEG. This allows for the possibility of spinal cord "reconstruction" in humans and even the possibility of head transplantation in the future.
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Affiliation(s)
- Yijie Ye
- Hand and Microsurgical Center, 2nd Affiliated Hospital, Harbin Medical University, Harbin, China; State-Province Key Laboratories of Biomedicine-Pharmaceutics, Harbin Medical University, Harbin, China
| | - C-Yoon Kim
- College of Life Science, Department of Bioengineering, CHA University, Seoul, Korea; Department of Laboratory Animal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | - Qing Miao
- Hand and Microsurgical Center, 2nd Affiliated Hospital, Harbin Medical University, Harbin, China; State-Province Key Laboratories of Biomedicine-Pharmaceutics, Harbin Medical University, Harbin, China
| | - Xiaoping Ren
- Hand and Microsurgical Center, 2nd Affiliated Hospital, Harbin Medical University, Harbin, China; State-Province Key Laboratories of Biomedicine-Pharmaceutics, Harbin Medical University, Harbin, China.
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