1
|
Gál L, Bellák T, Marton A, Fekécs Z, Weissman D, Török D, Biju R, Vizler C, Kristóf R, Beattie MB, Lin PJ, Pardi N, Nógrádi A, Pajer K. Restoration of Motor Function through Delayed Intraspinal Delivery of Human IL-10-Encoding Nucleoside-Modified mRNA after Spinal Cord Injury. RESEARCH (WASHINGTON, D.C.) 2023; 6:0056. [PMID: 36930811 PMCID: PMC10013810 DOI: 10.34133/research.0056] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 01/05/2023] [Indexed: 01/13/2023]
Abstract
Efficient in vivo delivery of anti-inflammatory proteins to modulate the microenvironment of an injured spinal cord and promote neuroprotection and functional recovery is a great challenge. Nucleoside-modified messenger RNA (mRNA) has become a promising new modality that can be utilized for the safe and efficient delivery of therapeutic proteins. Here, we used lipid nanoparticle (LNP)-encapsulated human interleukin-10 (hIL-10)-encoding nucleoside-modified mRNA to induce neuroprotection and functional recovery following rat spinal cord contusion injury. Intralesional administration of hIL-10 mRNA-LNP to rats led to a remarkable reduction of the microglia/macrophage reaction in the injured spinal segment and induced significant functional recovery compared to controls. Furthermore, hIL-10 mRNA treatment induced increased expression in tissue inhibitor of matrix metalloproteinase 1 and ciliary neurotrophic factor levels in the affected spinal segment indicating a time-delayed secondary effect of IL-10 5 d after injection. Our results suggest that treatment with nucleoside-modified mRNAs encoding neuroprotective factors is an effective strategy for spinal cord injury repair.
Collapse
Affiliation(s)
- László Gál
- Department of Anatomy, Histology and Embryology, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - Tamás Bellák
- Department of Anatomy, Histology and Embryology, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - Annamária Marton
- National Biotechnology Laboratory, Institute of Genetics, Biological Research Centre, Szeged, Hungary
- Institute of Biochemistry, Biological Research Centre, Szeged, Hungary
| | - Zoltán Fekécs
- Department of Anatomy, Histology and Embryology, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - Drew Weissman
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Dénes Török
- Department of Anatomy, Histology and Embryology, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - Rachana Biju
- Department of Anatomy, Histology and Embryology, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - Csaba Vizler
- National Biotechnology Laboratory, Institute of Genetics, Biological Research Centre, Szeged, Hungary
- Institute of Biochemistry, Biological Research Centre, Szeged, Hungary
| | - Rebeka Kristóf
- Department of Anatomy, Histology and Embryology, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | | | | | - Norbert Pardi
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Antal Nógrádi
- Department of Anatomy, Histology and Embryology, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| | - Krisztián Pajer
- Department of Anatomy, Histology and Embryology, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary
| |
Collapse
|
2
|
Zochodne DW. Growth factors and molecular-driven plasticity in neurological systems. HANDBOOK OF CLINICAL NEUROLOGY 2023; 196:569-598. [PMID: 37620091 DOI: 10.1016/b978-0-323-98817-9.00017-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/26/2023]
Abstract
It has been almost 70 years since the discovery of nerve growth factor (NGF), a period of a dramatic evolution in our understanding of dynamic growth, regeneration, and rewiring of the nervous system. In 1953, the extraordinary finding that a protein found in mouse submandibular glands generated a halo of outgrowing axons has now redefined our concept of the nervous system connectome. Central and peripheral neurons and their axons or dendrites are no longer considered fixed or static "wiring." Exploiting this molecular-driven plasticity as a therapeutic approach has arrived in the clinic with a slate of new trials and ideas. Neural growth factors (GFs), soluble proteins that alter the behavior of neurons, have expanded in numbers and our understanding of the complexity of their signaling and interactions with other proteins has intensified. However, beyond these "extrinsic" determinants of neuron growth and function are the downstream pathways that impact neurons, ripe for translational development and potentially more important than individual growth factors that may trigger them. Persistent and ongoing nuances in clinical trial design in some of the most intractable and irreversible neurological conditions give hope for connecting new biological ideas with clinical benefits. This review is a targeted update on neural GFs, their signals, and new therapeutic ideas, selected from an expansive literature.
Collapse
Affiliation(s)
- Douglas W Zochodne
- Division of Neurology, Department of Medicine and Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada.
| |
Collapse
|
3
|
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.
Collapse
|
4
|
Ji-wei S, Zi-ying L, Xiang T, Yang Y, Ju-fen Z, Qing-hua Z. CNTF induces Clcf1 in astrocytes to promote the differentiation of oligodendrocyte precursor cells. Biochem Biophys Res Commun 2022; 636:170-177. [DOI: 10.1016/j.bbrc.2022.10.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 10/01/2022] [Accepted: 10/03/2022] [Indexed: 11/16/2022]
|
5
|
Zheng Y, Gallegos CM, Xue H, Li S, Kim DH, Zhou H, Xia X, Liu Y, Cao Q. Transplantation of Human Induced Pluripotent Stem Cell-Derived Neural Progenitor Cells Promotes Forelimb Functional Recovery after Cervical Spinal Cord Injury. Cells 2022; 11:cells11172765. [PMID: 36078173 PMCID: PMC9454923 DOI: 10.3390/cells11172765] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 08/29/2022] [Accepted: 09/02/2022] [Indexed: 01/05/2023] Open
Abstract
Locomotor function after spinal cord injury (SCI) is critical for assessing recovery. Currently, available means to improve locomotor function include surgery, physical therapy rehabilitation and exoskeleton. Stem cell therapy with neural progenitor cells (NPCs) transplantation is a promising reparative strategy. Along this line, patient-specific induced pluripotent stem cells (iPSCs) are a remarkable autologous cell source, which offer many advantages including: great potential to generate isografts avoiding immunosuppression; the availability of a variety of somatic cells without ethical controversy related to embryo use; and vast differentiation. In this current work, to realize the therapeutic potential of iPSC-NPCs for the treatment of SCI, we transplanted purified iPSCs-derived NPCs into a cervical contusion SCI rat model. Our results showed that the iPSC-NPCs were able to survive and differentiate into both neurons and astrocytes and, importantly, improve forelimb locomotor function as assessed by the grooming task and horizontal ladder test. Purified iPSC-NPCs represent a promising cell type that could be further tested and developed into a clinically useful cell source for targeted cell therapy for cervical SCI patients.
Collapse
Affiliation(s)
- Yiyan Zheng
- Center for Translational Science, Florida International University, 11350 SW Village Pkwy, Port St. Lucie, FL 34987, USA
- Robert Stempel College of Public Health and Social Work, Florida International University, 11350 SW Village Pkwy, Port St. Lucie, FL 34987, USA
- Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
- Center for Stem Cell and Regenerative Medicine, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Chrystine M. Gallegos
- Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
- Center for Stem Cell and Regenerative Medicine, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Haipeng Xue
- Center for Translational Science, Florida International University, 11350 SW Village Pkwy, Port St. Lucie, FL 34987, USA
- Robert Stempel College of Public Health and Social Work, Florida International University, 11350 SW Village Pkwy, Port St. Lucie, FL 34987, USA
- Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
- Center for Stem Cell and Regenerative Medicine, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Shenglan Li
- Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
- Center for Stem Cell and Regenerative Medicine, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Dong H. Kim
- Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
- Center for Stem Cell and Regenerative Medicine, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Hongxia Zhou
- Center for Translational Science, Florida International University, 11350 SW Village Pkwy, Port St. Lucie, FL 34987, USA
- Robert Stempel College of Public Health and Social Work, Florida International University, 11350 SW Village Pkwy, Port St. Lucie, FL 34987, USA
| | - Xugang Xia
- Center for Translational Science, Florida International University, 11350 SW Village Pkwy, Port St. Lucie, FL 34987, USA
- Robert Stempel College of Public Health and Social Work, Florida International University, 11350 SW Village Pkwy, Port St. Lucie, FL 34987, USA
| | - Ying Liu
- Center for Translational Science, Florida International University, 11350 SW Village Pkwy, Port St. Lucie, FL 34987, USA
- Robert Stempel College of Public Health and Social Work, Florida International University, 11350 SW Village Pkwy, Port St. Lucie, FL 34987, USA
- Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
- Center for Stem Cell and Regenerative Medicine, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
- Correspondence: (Y.L.); (Q.C.); Tel.: +1-(772)-345-4734 (Y.L.); +1-(772)-345-4622 (Q.C.)
| | - Qilin Cao
- Center for Translational Science, Florida International University, 11350 SW Village Pkwy, Port St. Lucie, FL 34987, USA
- Robert Stempel College of Public Health and Social Work, Florida International University, 11350 SW Village Pkwy, Port St. Lucie, FL 34987, USA
- Department of Neurosurgery, McGovern Medical School, University of Texas Health Science Center at Houston, 6431 Fannin St., Houston, TX 77030, USA
- Center for Stem Cell and Regenerative Medicine, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
- Correspondence: (Y.L.); (Q.C.); Tel.: +1-(772)-345-4734 (Y.L.); +1-(772)-345-4622 (Q.C.)
| |
Collapse
|
6
|
Kiaie N, Gorabi AM, Loveless R, Teng Y, Jamialahmadi T, Sahebkar A. The regenerative potential of glial progenitor cells and reactive astrocytes in CNS injuries. Neurosci Biobehav Rev 2022; 140:104794. [PMID: 35902044 DOI: 10.1016/j.neubiorev.2022.104794] [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: 02/18/2022] [Revised: 07/20/2022] [Accepted: 07/21/2022] [Indexed: 10/16/2022]
Abstract
Cell therapeutic approaches focusing on the regeneration of damaged tissue have been a popular topic among researchers in recent years. In particular, self-repair scarring from the central nervous system (CNS) can significantly complicate the treatment of an injured patient. In CNS regeneration schemes, either glial progenitor cells or reactive glial cells have key roles to play. In this review, the contribution and underlying mechanisms of these progenitor/reactive glial cells during CNS regeneration are discussed, as well as their role in CNS-related diseases.
Collapse
Affiliation(s)
- Nasim Kiaie
- Research Center for Advanced Technologies in Cardiovascular Medicine, Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Armita Mahdavi Gorabi
- Department of Tissue Engineering and Applied Cell Science, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Reid Loveless
- Department of Oral Biology and Diagnostic Sciences, Dental College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Yong Teng
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA, USA
| | - Tannaz Jamialahmadi
- Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; Department of Nutrition, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Amirhossein Sahebkar
- Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran; Department of Biotechnology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.
| |
Collapse
|
7
|
He T, Yang GY, Zhang Z. Crosstalk of Astrocytes and Other Cells during Ischemic Stroke. LIFE (BASEL, SWITZERLAND) 2022; 12:life12060910. [PMID: 35743941 PMCID: PMC9228674 DOI: 10.3390/life12060910] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 06/04/2022] [Accepted: 06/07/2022] [Indexed: 12/27/2022]
Abstract
Stroke is a leading cause of death and long-term disability worldwide. Astrocytes structurally compose tripartite synapses, blood–brain barrier, and the neurovascular unit and perform multiple functions through cell-to-cell signaling of neurons, glial cells, and vasculature. The crosstalk of astrocytes and other cells is complicated and incompletely understood. Here we review the role of astrocytes in response to ischemic stroke, both beneficial and detrimental, from a cell–cell interaction perspective. Reactive astrocytes provide neuroprotection through antioxidation and antiexcitatory effects and metabolic support; they also contribute to neurorestoration involving neurogenesis, synaptogenesis, angiogenesis, and oligodendrogenesis by crosstalk with stem cells and cell lineage. In the meantime, reactive astrocytes also play a vital role in neuroinflammation and brain edema. Glial scar formation in the chronic phase hinders functional recovery. We further discuss astrocyte enriched microRNAs and exosomes in the regulation of ischemic stroke. In addition, the latest notion of reactive astrocyte subsets and astrocytic activity revealed by optogenetics is mentioned. This review discusses the current understanding of the intimate molecular conversation between astrocytes and other cells and outlines its potential implications after ischemic stroke. “Neurocentric” strategies may not be sufficient for neurological protection and recovery; future therapeutic strategies could target reactive astrocytes.
Collapse
Affiliation(s)
- Tingting He
- Department of Neurology, Shanghai Tenth People’s Hospital, Tongji University, Shanghai 200072, China;
- Neuroscience and Neuroengineering Center, Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
| | - Guo-Yuan Yang
- Neuroscience and Neuroengineering Center, Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
- Correspondence: (G.-Y.Y.); (Z.Z.); Tel.: +86-21-62933186 (G.-Y.Y.); Fax: +86-21-62932302 (G.-Y.Y.)
| | - Zhijun Zhang
- Neuroscience and Neuroengineering Center, Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
- Correspondence: (G.-Y.Y.); (Z.Z.); Tel.: +86-21-62933186 (G.-Y.Y.); Fax: +86-21-62932302 (G.-Y.Y.)
| |
Collapse
|
8
|
Yousefifard M, Sarveazad A, Babahajian A, Rafiei Alavi SN, Neishaboori AM, Vaccaro AR, Hosseini M, Rahimi-Movaghar V. Growth Factor Gene-Modified Cells in Spinal Cord Injury Recovery; a Systematic Review. World Neurosurg 2022; 162:150-162.e1. [PMID: 35276395 DOI: 10.1016/j.wneu.2022.03.012] [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: 12/12/2021] [Revised: 03/01/2022] [Accepted: 03/02/2022] [Indexed: 10/18/2022]
Abstract
BACKGROUND Numerous pre-clinical studies have been performed in recent years on the effects of growth factor gene-modified cells' administration in spinal cord injury (SCI). However, findings of these studies are contradictory. OBJECTIVE The present study aims to conduct a systematic review and meta-analysis on animal studies evaluating the effects of growth factor gene-modified cells' administration on locomotion recovery following SCI. METHODS A search of the Medline, Embase, Scopus and Web of Science databases was conducted, including all animal studies until the end of 2020. Two researchers screened search results, summarized relevant studies and assessed risk of bias, independently. RESULTS Thirty-three studies were included in the final analysis. Transplantation of growth factor gene-modified cells in the injured spinal cord resulted in a significant improvement in animals' locomotion compared with non-treated animals [standardized mean difference (SMD)=1.86; 95% CI: 1.39-2.33; p<0.0001)] and non-genetically modified cells treated animals (SMD=1.30; 0.80-1.79; p<0.0001). Transplantation efficacy of these cells failed to achieve significance in moderate lesions (p=0.091), when using modified neural stem/progenitor cells (p=0.164), when using synthetic neurotrophins (p=0.086) and when the number of transplanted cells was less than 1.0 × 105 cells per animal (p = 0.119). CONCLUSION The result showed that transplantation of growth factor gene-modified cells significantly improved locomotion in SCI animal models. However, there is a major concern regarding the safety of genetically modified cells' transplantation, in terms of overexpressing growth factors. Further studies are needed before any effort to perform a translational and clinical study.
Collapse
Affiliation(s)
- Mahmoud Yousefifard
- Physiology Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Arash Sarveazad
- Colorectal Research Center, Iran University of Medical Sciences, Tehran, Iran; Nursing Care Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Asrin Babahajian
- Liver and digestive research center, Research Institute for Health Development, Kurdistan University of Medical Sciences, Sanandaj, Iran
| | | | | | - Alex R Vaccaro
- Department of Orthopedics and Neurosurgery, Rothman Institute, Thomas Jefferson University, Philadelphia, USA
| | - Mostafa Hosseini
- Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
| | - Vafa Rahimi-Movaghar
- Sina Trauma and Surgery Research Center, Tehran University of Medical Sciences, Tehran, Iran; Brain and Spinal Injuries Research Center (BASIR), Neuroscience Institute, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
9
|
New Therapy for Spinal Cord Injury: Autologous Genetically-Enriched Leucoconcentrate Integrated with Epidural Electrical Stimulation. Cells 2022; 11:cells11010144. [PMID: 35011706 PMCID: PMC8750549 DOI: 10.3390/cells11010144] [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: 11/22/2021] [Revised: 12/07/2021] [Accepted: 12/29/2021] [Indexed: 12/17/2022] Open
Abstract
The contemporary strategy for spinal cord injury (SCI) therapy aims to combine multiple approaches to control pathogenic mechanisms of neurodegeneration and stimulate neuroregeneration. In this study, a novel regenerative approach using an autologous leucoconcentrate enriched with transgenes encoding vascular endothelial growth factor (VEGF), glial cell line-derived neurotrophic factor (GDNF), and neural cell adhesion molecule (NCAM) combined with supra- and sub-lesional epidural electrical stimulation (EES) was tested on mini-pigs similar in morpho-physiological scale to humans. The complex analysis of the spinal cord recovery after a moderate contusion injury in treated mini-pigs compared to control animals revealed: better performance in behavioural and joint kinematics, restoration of electromyography characteristics, and improvement in selected immunohistology features related to cell survivability, synaptic protein expression, and glial reorganization above and below the injury. These results for the first time demonstrate the positive effect of intravenous infusion of autologous genetically-enriched leucoconcentrate producing recombinant molecules stimulating neuroregeneration combined with neuromodulation by translesional multisite EES on the restoration of the post-traumatic spinal cord in mini-pigs and suggest the high translational potential of this novel regenerative therapy for SCI patients.
Collapse
|
10
|
Lai BQ, Bai YR, Han WT, Zhang B, Liu S, Sun JH, Liu JL, Li G, Zeng X, Ding Y, Ma YH, Zhang L, Chen ZH, Wang J, Xiong Y, Wu JH, Quan Q, Xing LY, Zhang HB, Zeng YS. Construction of a niche-specific spinal white matter-like tissue to promote directional axon regeneration and myelination for rat spinal cord injury repair. Bioact Mater 2021; 11:15-31. [PMID: 34938909 DOI: 10.1016/j.bioactmat.2021.10.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 09/29/2021] [Accepted: 10/03/2021] [Indexed: 12/16/2022] Open
Abstract
Directional axon regeneration and remyelination are crucial for repair of spinal cord injury (SCI), but existing treatments do not effectively promote those processes. Here, we propose a strategy for construction of niche-specific spinal white matter-like tissue (WMLT) using decellularized optic nerve (DON) loaded with neurotrophin-3 (NT-3)-overexpressing oligodendrocyte precursor cells. A rat model with a white matter defect in the dorsal spinal cord of the T10 segment was used. The WMLT transplantation group showed significant improvement in coordinated motor functions compared with the control groups. WMLT transplants integrated well with host spinal cord white matter, effectively addressing several barriers to directional axonal regeneration and myelination during SCI repair. In WMLT, laminin was found to promote development of oligodendroglial lineage (OL) cells by binding to laminin receptors. Interestingly, laminin could also guide linear axon regeneration via interactions with specific integrins on the axon surface. The WMLT developed here utilizes the unique microstructure and bioactive matrix of DON to create a niche rich in laminin, NT-3 and OL cells to achieve significant structural repair of SCI. Our protocol can help to promote research on repair of nerve injury and construction of neural tissues and organoids that form specific cell niches.
Collapse
Affiliation(s)
- Bi-Qin Lai
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat-sen University), Ministry of Education, Guangzhou, 510080, China.,Department of Histology and Embryology, Zhongshan School of Medicine, SunYat-sen University, Guangzhou, 510080, China.,Institute of Spinal Cord Injury, Sun Yat-sen University, Guangzhou, 510120, China.,Co-innovation Center of Neuroregeneration, Nantong University, Nantong, 226001, China.,Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| | - Yu-Rong Bai
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat-sen University), Ministry of Education, Guangzhou, 510080, China
| | - Wei-Tao Han
- Department of Histology and Embryology, Zhongshan School of Medicine, SunYat-sen University, Guangzhou, 510080, China
| | - Bao Zhang
- Department of Histology and Embryology, Zhongshan School of Medicine, SunYat-sen University, Guangzhou, 510080, China
| | - Shu Liu
- Department of Anatomy, Anhui Medical University, Hefei, 230032, China
| | - Jia-Hui Sun
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat-sen University), Ministry of Education, Guangzhou, 510080, China
| | - Jia-Lin Liu
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat-sen University), Ministry of Education, Guangzhou, 510080, China
| | - Ge Li
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat-sen University), Ministry of Education, Guangzhou, 510080, China
| | - Xiang Zeng
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat-sen University), Ministry of Education, Guangzhou, 510080, China.,Department of Histology and Embryology, Zhongshan School of Medicine, SunYat-sen University, Guangzhou, 510080, China.,Institute of Spinal Cord Injury, Sun Yat-sen University, Guangzhou, 510120, China.,Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| | - Ying Ding
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat-sen University), Ministry of Education, Guangzhou, 510080, China.,Department of Histology and Embryology, Zhongshan School of Medicine, SunYat-sen University, Guangzhou, 510080, China.,Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| | - Yuan-Huan Ma
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat-sen University), Ministry of Education, Guangzhou, 510080, China
| | - Ling Zhang
- Department of Geriatrics, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, 510080, China
| | - Zheng-Hong Chen
- Department of Geriatrics, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, 510080, China
| | - Jun Wang
- Physiotherapy Department, Guangdong Work Injury Rehabilitation Hospital, Guangzhou, China
| | - Yuan Xiong
- Physiotherapy Department, Guangdong Work Injury Rehabilitation Hospital, Guangzhou, China
| | - Jin-Hua Wu
- Physiotherapy Department, Guangdong Work Injury Rehabilitation Hospital, Guangzhou, China
| | - Qi Quan
- Department of Orthopedic Surgery, Key Laboratory of Musculoskeletal Trauma &War Injuries PLA, Beijing Key Lab of Regenerative Medicine in Orthopedics, The 4th Medical Centre, Chinese PLA General Hospital, Beijing, China
| | - Ling-Yan Xing
- Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| | - Hong-Bo Zhang
- Department of Histology and Embryology, Zhongshan School of Medicine, SunYat-sen University, Guangzhou, 510080, China
| | - Yuan-Shan Zeng
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat-sen University), Ministry of Education, Guangzhou, 510080, China.,Department of Histology and Embryology, Zhongshan School of Medicine, SunYat-sen University, Guangzhou, 510080, China.,Institute of Spinal Cord Injury, Sun Yat-sen University, Guangzhou, 510120, China.,Co-innovation Center of Neuroregeneration, Nantong University, Nantong, 226001, China.,Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| |
Collapse
|
11
|
Ma F, Wang H, Yang X, Wu Y, Liao C, Xie B, Li Y, Zhang W. Controlled release of ciliary neurotrophic factor from bioactive nerve grafts promotes nerve regeneration in rats with facial nerve injuries. J Biomed Mater Res A 2021; 110:788-796. [PMID: 34792847 DOI: 10.1002/jbm.a.37327] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 09/28/2021] [Accepted: 10/23/2021] [Indexed: 12/20/2022]
Abstract
It is critical to repair severed facial nerves, as lack of treatment may cause long-term motor and sensory impairments. Ciliary neurotrophic factor (CNTF) plays an important role in terms of enhancing nerve axon regrowth and maturation during peripheral nerve regeneration after injury. However, simple application of CNTF to the transected nerve site does not afford functional recovery, because it is rapidly flushed away by bodily fluids. The aim of the present study was the construction of a new, bioactive composite nerve graft facilitating persistent CNTF delivery to aid the reconstruction of facial nerve defects. The in vitro study showed that the bioactive nerve graft generated sustainable CNTF release for more than 25 days. The bioactive nerve graft was then transplanted into the injury sites of rat facial nerves. At 6 and 12 weeks post-transplantation, functional and histological analyses showed that the bioactive nerve graft featuring immobilized CNTF significantly enhanced nerve regeneration in terms of both axonal outgrowth and Schwann cell proliferation in the rat facial nerve gap model, compared to a collagen tube with adsorbed CNTF that initially released high levels of CNTF. The bioactive nerve graft may serve as novel, controlled bioactive release therapy for facial nerve regeneration.
Collapse
Affiliation(s)
- Fukai Ma
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Hanming Wang
- Department of Rehabilitation, Beijing Rehabilitation Hospital of Capital Medical University, Beijing, China
| | - Xiaosheng Yang
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yiwei Wu
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Chenlong Liao
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Bingran Xie
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yi Li
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Wenchuan Zhang
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| |
Collapse
|
12
|
Lai BQ, Zeng X, Han WT, Che MT, Ding Y, Li G, Zeng YS. Stem cell-derived neuronal relay strategies and functional electrical stimulation for treatment of spinal cord injury. Biomaterials 2021; 279:121211. [PMID: 34710795 DOI: 10.1016/j.biomaterials.2021.121211] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 10/09/2021] [Accepted: 10/20/2021] [Indexed: 01/06/2023]
Abstract
The inability of adult mammals to recover function lost after severe spinal cord injury (SCI) has been known for millennia and is mainly attributed to a failure of brain-derived nerve fiber regeneration across the lesion. Potential approaches to re-establishing locomotor function rely on neuronal relays to reconnect the segregated neural networks of the spinal cord. Intense research over the past 30 years has focused on endogenous and exogenous neuronal relays, but progress has been slow and the results often controversial. Treatments with stem cell-derived neuronal relays alone or together with functional electrical stimulation offer the possibility of improved repair of neuronal networks. In this review, we focus on approaches to recovery of motor function in paralyzed patients after severe SCI based on novel therapies such as implantation of stem cell-derived neuronal relays and functional electrical stimulation. Recent research progress offers hope that SCI patients will one day be able to recover motor function and sensory perception.
Collapse
Affiliation(s)
- Bi-Qin Lai
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat-sen University), Ministry of Education, Guangzhou, 510080, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, 226001, China
| | - Xiang Zeng
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat-sen University), Ministry of Education, Guangzhou, 510080, China
| | - Wei-Tao Han
- Department of Histology and Embryology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| | - Ming-Tian Che
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat-sen University), Ministry of Education, Guangzhou, 510080, China
| | - Ying Ding
- Department of Histology and Embryology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| | - Ge Li
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat-sen University), Ministry of Education, Guangzhou, 510080, China
| | - Yuan-Shan Zeng
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat-sen University), Ministry of Education, Guangzhou, 510080, China; Department of Histology and Embryology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China; Institute of Spinal Cord Injury, Sun Yat-sen University, Guangzhou, 510120, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, 226001, China; Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan, School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China.
| |
Collapse
|
13
|
Shinozaki M, Nagoshi N, Nakamura M, Okano H. Mechanisms of Stem Cell Therapy in Spinal Cord Injuries. Cells 2021; 10:cells10102676. [PMID: 34685655 PMCID: PMC8534136 DOI: 10.3390/cells10102676] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 09/28/2021] [Accepted: 10/04/2021] [Indexed: 12/13/2022] Open
Abstract
Every year, 0.93 million people worldwide suffer from spinal cord injury (SCI) with irretrievable sequelae. Rehabilitation, currently the only available treatment, does not restore damaged tissues; therefore, the functional recovery of patients remains limited. The pathophysiology of spinal cord injuries is heterogeneous, implying that potential therapeutic targets differ depending on the time of injury onset, the degree of injury, or the spinal level of injury. In recent years, despite a significant number of clinical trials based on various types of stem cells, these aspects of injury have not been effectively considered, resulting in difficult outcomes of trials. In a specialty such as cancerology, precision medicine based on a patient’s characteristics has brought indisputable therapeutic advances. The objective of the present review is to promote the development of precision medicine in the field of SCI. Here, we first describe the multifaceted pathophysiology of SCI, with the temporal changes after injury, the characteristics of the chronic phase, and the subtypes of complete injury. We then detail the appropriate targets and related mechanisms of the different types of stem cell therapy for each pathological condition. Finally, we highlight the great potential of stem cell therapy in cervical SCI.
Collapse
Affiliation(s)
- Munehisa Shinozaki
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan;
| | - Narihito Nagoshi
- Department of Orthopedic Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan; (N.N.); (M.N.)
| | - Masaya Nakamura
- Department of Orthopedic Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan; (N.N.); (M.N.)
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan;
- Correspondence:
| |
Collapse
|
14
|
Richard SA, Sackey M. Elucidating the Pivotal Neuroimmunomodulation of Stem Cells in Spinal Cord Injury Repair. Stem Cells Int 2021; 2021:9230866. [PMID: 34341666 PMCID: PMC8325586 DOI: 10.1155/2021/9230866] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 07/03/2021] [Accepted: 07/17/2021] [Indexed: 12/11/2022] Open
Abstract
Spinal cord injury (SCI) is a distressing incident with abrupt onset of the motor as well as sensory dysfunction, and most often, the injury occurs as result of high-energy or velocity accidents as well as contact sports and falls in the elderly. The key challenges associated with nerve repair are the lack of self-repair as well as neurotrophic factors and primary and secondary neuronal apoptosis, as well as factors that prevent the regeneration of axons locally. Neurons that survive the initial traumatic damage may be lost due to pathogenic activities like neuroinflammation and apoptosis. Implanted stem cells are capable of differentiating into neural cells that replace injured cells as well as offer local neurotrophic factors that aid neuroprotection, immunomodulation, axonal sprouting, axonal regeneration, and remyelination. At the microenvironment of SCI, stem cells are capable of producing growth factors like brain-derived neurotrophic factor and nerve growth factor which triggers neuronal survival as well as axonal regrowth. Although stem cells have proven to be of therapeutic value in SCI, the major disadvantage of some of the cell types is the risk for tumorigenicity due to the contamination of undifferentiated cells prior to transplantation. Local administration of stem cells via either direct cellular injection into the spinal cord parenchyma or intrathecal administration into the subarachnoid space is currently the best transplantation modality for stem cells during SCI.
Collapse
Affiliation(s)
- Seidu A. Richard
- Department of Medicine, Princefield University, P.O. Box MA128, Ho, Ghana
| | - Marian Sackey
- Department of Pharmacy, Ho Teaching Hospital, P.O. Box MA-374, Ho, Ghana
| |
Collapse
|
15
|
Topical application of CNTF, GDNF and BDNF in combination attenuates blood-spinal cord barrier permeability, edema formation, hemeoxygenase-2 upregulation, and cord pathology. PROGRESS IN BRAIN RESEARCH 2021; 266:357-376. [PMID: 34689864 DOI: 10.1016/bs.pbr.2021.06.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Spinal cord injury (SCI) is one of the leading causes of disability in Military personnel for which no suitable therapeutic strategies are available till today. Thus, exploration of novel therapeutic measures is highly needed to enhance the quality of life of SCI victims. Previously, topical application of BDNF and GDNF in combination over the injured spinal cord after 90min induced marked neuroprotection. In present investigation, we added CNTF in combination with BDNF and/or GDNF treatment to examine weather the triple combination applied over the traumatic cord after 90 or 120min could thwart cord pathology. Since neurotrophins attenuate nitric oxide (NO) production in SCI, the role of carbon monoxide (CO) production that is similar to NO in inducing cell injury was explored using immunohistochemistry of the constitutive isoform of enzyme hemeoxygenase-2 (HO-2). SCI inflicted over the right dorsal horn of the T10-11 segments by making an incision of 2mm deep and 5mm long upregulated the HO-2 immunostaining in the T9 and T12 segments after 5h injury. These perifocal segments are associated with breakdown of the blood-spinal cord barrier (BSCB), edema development and cell injuries. Topical application of CNTF with BDNF and GDNF in combination (10ng each) after 90 and 120min over the injured spinal cord significantly attenuated the BSCB breakdown, edema formation, cell injury and overexpression of HO-2. These observations are the first to show that CNTF with BDNF and GDNF induced superior neuroprotection in SCI probably by downregulation of CO production, not reported earlier.
Collapse
|
16
|
Hart CG, Karimi-Abdolrezaee S. Recent insights on astrocyte mechanisms in CNS homeostasis, pathology, and repair. J Neurosci Res 2021; 99:2427-2462. [PMID: 34259342 DOI: 10.1002/jnr.24922] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 06/06/2021] [Accepted: 06/24/2021] [Indexed: 12/20/2022]
Abstract
Astrocytes play essential roles in development, homeostasis, injury, and repair of the central nervous system (CNS). Their development is tightly regulated by distinct spatial and temporal cues during embryogenesis and into adulthood throughout the CNS. Astrocytes have several important responsibilities such as regulating blood flow and permeability of the blood-CNS barrier, glucose metabolism and storage, synapse formation and function, and axon myelination. In CNS pathologies, astrocytes also play critical parts in both injury and repair mechanisms. Upon injury, they undergo a robust phenotypic shift known as "reactive astrogliosis," which results in both constructive and deleterious outcomes. Astrocyte activation and migration at the site of injury provides an early defense mechanism to minimize the extent of injury by enveloping the lesion area. However, astrogliosis also contributes to the inhibitory microenvironment of CNS injury and potentiate secondary injury mechanisms, such as inflammation, oxidative stress, and glutamate excitotoxicity, which facilitate neurodegeneration in CNS pathologies. Intriguingly, reactive astrocytes are increasingly a focus in current therapeutic strategies as their activation can be modulated toward a neuroprotective and reparative phenotype. This review will discuss recent advancements in knowledge regarding the development and role of astrocytes in the healthy and pathological CNS. We will also review how astrocytes have been genetically modified to optimize their reparative potential after injury, and how they may be transdifferentiated into neurons and oligodendrocytes to promote repair after CNS injury and neurodegeneration.
Collapse
Affiliation(s)
- Christopher G Hart
- Department of Physiology and Pathophysiology, Spinal Cord Research Centre, Children's Hospital Research Institute of Manitoba, University of Manitoba, Winnipeg, MB, Canada
| | - Soheila Karimi-Abdolrezaee
- Department of Physiology and Pathophysiology, Spinal Cord Research Centre, Children's Hospital Research Institute of Manitoba, University of Manitoba, Winnipeg, MB, Canada
| |
Collapse
|
17
|
McIntyre WB, Pieczonka K, Khazaei M, Fehlings MG. Regenerative replacement of neural cells for treatment of spinal cord injury. Expert Opin Biol Ther 2021; 21:1411-1427. [PMID: 33830863 DOI: 10.1080/14712598.2021.1914582] [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: 10/21/2022]
Abstract
Introduction: Traumatic Spinal Cord Injury (SCI) results from primary physical injury to the spinal cord, which initiates a secondary cascade of neural cell death. Current therapeutic approaches can attenuate the consequences of the primary and secondary events, but do not address the degenerative aspects of SCI. Transplantation of neural stem/progenitor cells (NPCs) for the replacement of the lost/damaged neural cells is suggested here as a regenerative approach that is complementary to current therapeutics.Areas Covered: This review addresses how neurons, oligodendrocytes, and astrocytes are impacted by traumatic SCI, and how current research in regenerative-NPC therapeutics aims to restore their functionality. Methods used to enhance graft survival, as well as bias progenitor cells towards neuronal, oligodendrogenic, and astroglia lineages are discussed.Expert Opinion: Despite an NPC's ability to differentiate into neurons, oligodendrocytes, and astrocytes in the transplant environment, their potential therapeutic efficacy requires further optimization prior to translation into the clinic. Considering the temporospatial identity of NPCs could promote neural repair in region specific injuries throughout the spinal cord. Moreover, understanding which cells are targeted by NPC-derived myelinating cells can help restore physiologically-relevant myelin patterns. Finally, the duality of astrocytes is discussed, outlining their context-dependent importance in the treatment of SCI.
Collapse
Affiliation(s)
- William Brett McIntyre
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada.,Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
| | - Katarzyna Pieczonka
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada.,Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
| | - Mohamad Khazaei
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
| | - Michael G Fehlings
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada.,Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada.,Department of Surgery, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
18
|
Zeng CW, Sheu JC, Tsai HJ. The Neuronal Regeneration of Adult Zebrafish After Spinal Cord Injury Is Enhanced by Transplanting Optimized Number of Neural Progenitor Cells. Cell Transplant 2021; 29:963689720903679. [PMID: 32233781 PMCID: PMC7444222 DOI: 10.1177/0963689720903679] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Cell transplantation is commonly used to study the regeneration and
repair of the nervous system in animals. However, a technical platform
used to evaluate the optimum number of transplanted cells in the
recipient’s spinal cord is little reported. Therefore, to develop such
platform, we used a zebrafish model, which has transparent embryos,
and transgenic line huORFZ, which generates green
fluorescent protein (GFP)-expressing cells in the central nervous
system under hypoxic stress. After GFP-expressing cells, also termed
as hypoxia-responsive recovering cells, were obtained from
hypoxia-exposed huORFZ embryos, we transplanted these
GFP-(+) cells into the site of spinal cord injury (SCI) in adult
wild-type zebrafish, followed by assessing the relationship between
number of transplanted cells and the survival rate of recipients. When
100, 300, 500, and 1,000 GFP-(+) donor cells were transplanted into
the lesion site of SCI-treated recipients, we found that recipient
adult zebrafish transplanted with 300 donor cells had the highest
survival rate. Those GFP-(+) donor cells could undergo proliferation
and differentiation into neuron in recipients. Furthermore,
transplantation of GFP-(+) cells into adult zebrafish treated with SCI
was able to enhance the neuronal regeneration of recipients. In
contrast, those fish transplanted with over 500 cells showed signs of
inflammation around the SCI site, resulting in higher mortality. In
this study, we developed a technological platform for transplanting
cells into the lesion site of SCI-treated adult zebrafish and defined
the optimum number of successfully transplanted cells into recipients,
as 300, and those GFP-(+) donor cells could enhance recipient’s spinal
cord regeneration. Thus, we provided a practical methodology for
studying cell transplantation therapy in neuronal regeneration of
zebrafish after SCI.
Collapse
Affiliation(s)
- Chih-Wei Zeng
- Institute of Molecular and Cellular Biology, College of Life Science, National Taiwan University, Taipei.,Liver Disease Prevention and Treatment Research Foundation, Taipei
| | - Jin-Chuan Sheu
- Liver Disease Prevention and Treatment Research Foundation, Taipei
| | - Huai-Jen Tsai
- Institute of Biomedical Science, Mackay Medical College, New Taipei City
| |
Collapse
|
19
|
Muheremu A, Shu L, Liang J, Aili A, Jiang K. Sustained delivery of neurotrophic factors to treat spinal cord injury. Transl Neurosci 2021; 12:494-511. [PMID: 34900347 PMCID: PMC8633588 DOI: 10.1515/tnsci-2020-0200] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 11/04/2021] [Accepted: 11/05/2021] [Indexed: 12/16/2022] Open
Abstract
Acute spinal cord injury (SCI) is a devastating condition that results in tremendous physical and psychological harm and a series of socioeconomic problems. Although neurons in the spinal cord need neurotrophic factors for their survival and development to reestablish their connections with their original targets, endogenous neurotrophic factors are scarce and the sustainable delivery of exogeneous neurotrophic factors is challenging. The widely studied neurotrophic factors such as brain-derived neurotrophic factor, neurotrophin-3, nerve growth factor, ciliary neurotrophic factor, basic fibroblast growth factor, and glial cell-derived neurotrophic factor have a relatively short cycle that is not sufficient enough for functionally significant neural regeneration after SCI. In the past decades, scholars have tried a variety of cellular and viral vehicles as well as tissue engineering scaffolds to safely and sustainably deliver those necessary neurotrophic factors to the injury site, and achieved satisfactory neural repair and functional recovery on many occasions. Here, we review the neurotrophic factors that have been used in trials to treat SCI, and vehicles that were commonly used for their sustained delivery.
Collapse
Affiliation(s)
- Aikeremujiang Muheremu
- Department of Spine Surgery, Sixth Affiliated Hospital of Xinjiang Medical University, 39 Wuxing Nan Rd, Tianshan District, Urumqi, Xinjiang, 86830001, People’s Republic of China
| | - Li Shu
- Department of Orthopedics, Sixth Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang, 86830001, People’s Republic of China
| | - Jing Liang
- Department of Laboratory Medicine, Sixth Affiliated Hospital of Xinjiang Medical University, 39, Wuxing Nan Rd, Tianshan District, Urumqi, Xinjiang, 86830001, People’s Republic of China
| | - Abudunaibi Aili
- Department of Spine Surgery, Sixth Affiliated Hospital of Xinjiang Medical University, 39 Wuxing Nan Rd, Tianshan District, Urumqi, Xinjiang, 86830001, People’s Republic of China
| | - Kan Jiang
- Department of Orthopedics, Sixth Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang, 86830001, People’s Republic of China
| |
Collapse
|
20
|
Sahib S, Sharma A, Menon PK, Muresanu DF, Castellani RJ, Nozari A, Lafuente JV, Bryukhovetskiy I, Tian ZR, Patnaik R, Buzoianu AD, Wiklund L, Sharma HS. Cerebrolysin enhances spinal cord conduction and reduces blood-spinal cord barrier breakdown, edema formation, immediate early gene expression and cord pathology after injury. PROGRESS IN BRAIN RESEARCH 2020; 258:397-438. [PMID: 33223040 DOI: 10.1016/bs.pbr.2020.09.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Spinal cord evoked potentials (SCEP) are good indicators of spinal cord function in health and disease. Disturbances in SCEP amplitudes and latencies during spinal cord monitoring predict spinal cord pathology following trauma. Treatment with neuroprotective agents preserves SCEP and reduces cord pathology after injury. The possibility that cerebrolysin, a balanced composition of neurotrophic factors improves spinal cord conduction, attenuates blood-spinal cord barrier (BSCB) disruption, edema formation, and cord pathology was examined in spinal cord injury (SCI). SCEP is recorded from epidural space over rat spinal cord T9 and T12 segments after peripheral nerves stimulation. SCEP consists of a small positive peak (MPP), followed by a prominent negative peak (MNP) that is stable before SCI. A longitudinal incision (2mm deep and 5mm long) into the right dorsal horn (T10 and T11 segments) resulted in an immediate long-lasting depression of the rostral MNP with an increase in the latencies. Pretreatment with either cerebrolysin (CBL 5mL/kg, i.v. 30min before) alone or TiO2 nanowired delivery of cerebrolysin (NWCBL 2.5mL/kg, i.v.) prevented the loss of MNP amplitude and even enhanced further from the pre-injury level after SCI without affecting latencies. At 5h, SCI induced edema, BSCB breakdown, and cell injuries were significantly reduced by CBL and NWCBL pretreatment. Interestingly this effect on SCEP and cord pathology was still prominent when the NWCBL was delivered 2min after SCI. Moreover, expressions of c-fos and c-jun genes that are prominent at 5h in untreated SCI are also considerably reduced by CBL and NWCBL treatment. These results are the first to show that CBL and NWCBL enhanced SCEP activity and thwarted the development of cord pathology after SCI. Furthermore, NWCBL in low doses has superior neuroprotective effects on SCEP and cord pathology, not reported earlier. The functional significance and future clinical potential of CBL and NWCBL in SCI are discussed.
Collapse
Affiliation(s)
- Seaab Sahib
- Department of Chemistry & Biochemistry, University of Arkansas, Fayetteville, AR, United States
| | - Aruna Sharma
- International Experimental Central Nervous System Injury & Repair (IECNSIR), Department of Surgical Sciences, Anesthesiology & Intensive Care Medicine, Uppsala University Hospital, Uppsala University, Uppsala, Sweden.
| | - Preeti K Menon
- International Experimental Central Nervous System Injury & Repair (IECNSIR), Department of Surgical Sciences, Anesthesiology & Intensive Care Medicine, Uppsala University Hospital, Uppsala University, Uppsala, Sweden; Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden
| | - Dafin F Muresanu
- Department of Clinical Neurosciences, University of Medicine & Pharmacy, Cluj-Napoca, Romania; "RoNeuro" Institute for Neurological Research and Diagnostic, Cluj-Napoca, Romania
| | - Rudy J Castellani
- Department of Pathology, University of Maryland, Baltimore, MD, United States
| | - Ala Nozari
- Anesthesiology & Intensive Care, Massachusetts General Hospital, Boston, MA, United States
| | - José Vicente Lafuente
- LaNCE, Department of Neuroscience, University of the Basque Country (UPV/EHU), Leioa, Bizkaia, Spain
| | - Igor Bryukhovetskiy
- Department of Fundamental Medicine, School of Biomedicine, Far Eastern Federal University, Vladivostok, Russia; Laboratory of Pharmacology, National Scientific Center of Marine Biology, Far East Branch of the Russian Academy of Sciences, Vladivostok, Russia
| | - Z Ryan Tian
- Department of Chemistry & Biochemistry, University of Arkansas, Fayetteville, AR, United States
| | - Ranjana Patnaik
- Department of Biomaterials, School of Biomedical Engineering, Indian Institute of Technology, Banaras Hindu University, Varanasi, India
| | - Anca D Buzoianu
- Department of Clinical Pharmacology and Toxicology, "Iuliu Hatieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Lars Wiklund
- International Experimental Central Nervous System Injury & Repair (IECNSIR), Department of Surgical Sciences, Anesthesiology & Intensive Care Medicine, Uppsala University Hospital, Uppsala University, Uppsala, Sweden
| | - Hari Shanker Sharma
- International Experimental Central Nervous System Injury & Repair (IECNSIR), Department of Surgical Sciences, Anesthesiology & Intensive Care Medicine, Uppsala University Hospital, Uppsala University, Uppsala, Sweden.
| |
Collapse
|
21
|
Sphingosine-1-Phosphate Receptor Modulators and Oligodendroglial Cells: Beyond Immunomodulation. Int J Mol Sci 2020; 21:ijms21207537. [PMID: 33066042 PMCID: PMC7588977 DOI: 10.3390/ijms21207537] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 10/08/2020] [Accepted: 10/10/2020] [Indexed: 12/23/2022] Open
Abstract
Multiple sclerosis (MS) is an autoimmune inflammatory disease characterized by demyelination, axonal loss, and synaptic impairment in the central nervous system (CNS). The available therapies aim to reduce the severity of the pathology during the early inflammatory stages, but they are not effective in the chronic stage of the disease. In this phase, failure in endogenous remyelination is associated with the impairment of oligodendrocytes progenitor cells (OPCs) to migrate and differentiate into mature myelinating oligodendrocytes. Therefore, stimulating differentiation of OPCs into myelinating oligodendrocytes has become one of the main goals of new therapeutic approaches for MS. Different disease-modifying therapies targeting sphingosine-1-phosphate receptors (S1PRs) have been approved or are being developed to treat MS. Besides their immunomodulatory effects, growing evidence suggests that targeting S1PRs modulates mechanisms beyond immunomodulation, such as remyelination. In this context, this review focuses on the current understanding of S1PR modulators and their direct effect on OPCs and oligodendrocytes.
Collapse
|
22
|
Gallegos C, Carey M, Zheng Y, He X, Cao QL. Reaching and Grasping Training Improves Functional Recovery After Chronic Cervical Spinal Cord Injury. Front Cell Neurosci 2020; 14:110. [PMID: 32536855 PMCID: PMC7266985 DOI: 10.3389/fncel.2020.00110] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 04/08/2020] [Indexed: 12/31/2022] Open
Abstract
Previous studies suggest locomotion training could be an effective non-invasive therapy after spinal cord injury (SCI) using primarily acute thoracic injuries. However, the majority of SCI patients have chronic cervical injuries. Regaining hand function could significantly increase their quality of life. In this study, we used a clinically relevant chronic cervical contusion to study the therapeutic efficacy of rehabilitation in forelimb functional recovery. Nude rats received a moderate C5 unilateral contusive injury and were then divided into two groups with or without Modified Montoya Staircase (MMS) rehabilitation. For the rehabilitation group, rats were trained 5 days a week starting at 8 weeks post-injury (PI) for 6 weeks. All rats were assessed for skilled forelimb functions with MMS test weekly and for untrained gross forelimb locomotion with grooming and horizontal ladder (HL) tests biweekly. Our results showed that MMS rehabilitation significantly increased the number of pellets taken at 13 and 14 weeks PI and the accuracy rates at 12 to 14 weeks PI. However, there were no significant differences in the grooming scores or the percentage of HL missteps at any time point. Histological analyses revealed that MMS rehabilitation significantly increased the number of serotonergic fibers and the amount of presynaptic terminals around motor neurons in the cervical ventral horns caudal to the injury and reduced glial fibrillary acidic protein (GFAP)-immunoreactive astrogliosis in spinal cords caudal to the lesion. This study shows that MMS rehabilitation can modify the injury environment, promote axonal sprouting and synaptic plasticity, and importantly, improve reaching and grasping functions in the forelimb, supporting the therapeutic potential of task-specific rehabilitation for functional recovery after chronic SCI.
Collapse
Affiliation(s)
- Chrystine Gallegos
- The Vivian L. Smith Department of Neurosurgery, The University of Texas Health Science Center at Houston, Houston, TX, United States.,Center for Stem Cell and Regenerative Medicine, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Matthew Carey
- The Vivian L. Smith Department of Neurosurgery, The University of Texas Health Science Center at Houston, Houston, TX, United States.,Center for Stem Cell and Regenerative Medicine, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health Science Center at Houston, Houston, TX, United States.,Summer Undergraduate Research Program, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Yiyan Zheng
- The Vivian L. Smith Department of Neurosurgery, The University of Texas Health Science Center at Houston, Houston, TX, United States.,Center for Stem Cell and Regenerative Medicine, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Xiuquan He
- The Vivian L. Smith Department of Neurosurgery, The University of Texas Health Science Center at Houston, Houston, TX, United States.,Center for Stem Cell and Regenerative Medicine, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health Science Center at Houston, Houston, TX, United States.,Department of Anatomy and Histoembryology, School of Basic Medical Sciences, Shandong University, Jinan, China
| | - Qi Lin Cao
- The Vivian L. Smith Department of Neurosurgery, The University of Texas Health Science Center at Houston, Houston, TX, United States.,Center for Stem Cell and Regenerative Medicine, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, The University of Texas Health Science Center at Houston, Houston, TX, United States
| |
Collapse
|
23
|
Jin MC, Medress ZA, Azad TD, Doulames VM, Veeravagu A. Stem cell therapies for acute spinal cord injury in humans: a review. Neurosurg Focus 2020; 46:E10. [PMID: 30835679 DOI: 10.3171/2018.12.focus18602] [Citation(s) in RCA: 83] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 12/11/2018] [Indexed: 12/21/2022]
Abstract
Recent advances in stem cell biology present significant opportunities to advance clinical applications of stem cell-based therapies for spinal cord injury (SCI). In this review, the authors critically analyze the basic science and translational evidence that supports the use of various stem cell sources, including induced pluripotent stem cells, oligodendrocyte precursor cells, and mesenchymal stem cells. They subsequently explore recent advances in stem cell biology and discuss ongoing clinical translation efforts, including combinatorial strategies utilizing scaffolds, biogels, and growth factors to augment stem cell survival, function, and engraftment. Finally, the authors discuss the evolution of stem cell therapies for SCI by providing an overview of completed (n = 18) and ongoing (n = 9) clinical trials.
Collapse
|
24
|
Zhou P, Guan J, Xu P, Zhao J, Zhang C, Zhang B, Mao Y, Cui W. Cell Therapeutic Strategies for Spinal Cord Injury. Adv Wound Care (New Rochelle) 2019; 8:585-605. [PMID: 31637103 PMCID: PMC6798812 DOI: 10.1089/wound.2019.1046] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Accepted: 08/27/2019] [Indexed: 12/13/2022] Open
Abstract
Significance: Spinal cord injury (SCI) is a neurological disorder that resulted from destroyed long axis of spinal cord, affecting thousands of people every year. With the occurrence of SCI, the lesions can form cystic cavities and produce glial scar, myelin inhibitor, and inflammation that negatively impact repair of spinal cord. Therefore, SCI remains a difficult problem to overcome with present therapeutics. This review of cell therapeutics in SCI provides a systematic review of combinatory therapeutics of SCI and helps the realization of regeneration of spinal cord in the future. Recent Advances: With major breakthroughs in neurobiology in recent years, present therapeutic strategies for SCI mainly aim at nerve regeneration or neuroprotection. For nerve regeneration, the application approaches are tissue engineering and cell transplantation, while drug therapeutics is applied for neuroprotection. Cell therapeutics is a new approach that treats SCI by cell transplantation. Cell therapeutics possesses advantages of neuroprotection, immune regulation, axonal regeneration, neuron relay formation, and remyelination. Critical Issues: Neurons cannot regenerate at the site of injury. Therefore, it is essential to find a repair strategy for remyelination, axon regeneration, and functional recovery. Cell therapeutics is emerging as the most promising approach for treating SCI. Future Directions: The future application of SCI therapy in clinical practice may require a combination of multiple strategies. A comprehensive treatment of injury of spinal cord is the focus of the present research. With the combination of different cell therapy strategies, future experiments will achieve more dramatic success in spinal cord repair.
Collapse
Affiliation(s)
- Pinghui Zhou
- Department of Orthopedics, First Affiliated Hospital of Bengbu Medical College, Bengbu, P.R. China
- Anhui Province Key Laboratory of Tissue Transplantation, Bengbu Medical College, Bengbu, P.R. China
| | - Jingjing Guan
- Department of Orthopedics, First Affiliated Hospital of Bengbu Medical College, Bengbu, P.R. China
| | - Panpan Xu
- Department of Orthopedics, First Affiliated Hospital of Bengbu Medical College, Bengbu, P.R. China
| | - Jingwen Zhao
- Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China
| | - Changchun Zhang
- Department of Orthopedics, First Affiliated Hospital of Bengbu Medical College, Bengbu, P.R. China
| | - Bin Zhang
- Department of Orthopedics, First Affiliated Hospital of Bengbu Medical College, Bengbu, P.R. China
| | - Yingji Mao
- Department of Orthopedics, First Affiliated Hospital of Bengbu Medical College, Bengbu, P.R. China
- School of Life Science, Bengbu Medical College, Bengbu, P.R. China
| | - Wenguo Cui
- Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China
| |
Collapse
|
25
|
Ashammakhi N, Kim HJ, Ehsanipour A, Bierman RD, Kaarela O, Xue C, Khademhosseini A, Seidlits SK. Regenerative Therapies for Spinal Cord Injury. TISSUE ENGINEERING PART B-REVIEWS 2019; 25:471-491. [PMID: 31452463 DOI: 10.1089/ten.teb.2019.0182] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Spinal cord injury (SCI) is a serious problem that primarily affects younger and middle-aged adults at its onset. To date, no effective regenerative treatment has been developed. Over the last decade, researchers have made significant advances in stem cell technology, biomaterials, nanotechnology, and immune engineering, which may be applied as regenerative therapies for the spinal cord. Although the results of clinical trials using specific cell-based therapies have proven safe, their efficacy has not yet been demonstrated. The pathophysiology of SCI is multifaceted, complex and yet to be fully understood. Thus, combinatorial therapies that simultaneously leverage multiple approaches will likely be required to achieve satisfactory outcomes. Although combinations of biomaterials with pharmacologic agents or cells have been explored, few studies have combined these modalities in a systematic way. For most strategies, clinical translation will be facilitated by the use of minimally invasive therapies, which are the focus of this review. In addition, this review discusses previously explored therapies designed to promote neuroregeneration and neuroprotection after SCI, while highlighting present challenges and future directions. Impact Statement To date there are no effective treatments that can regenerate the spinal cord after injury. Although there have been significant preclinical advances in bioengineering and regenerative medicine over the last decade, these have not translated into effective clinical therapies for spinal cord injury. This review focuses on minimally invasive therapies, providing extensive background as well as updates on recent technological developments and current clinical trials. This review is a comprehensive resource for researchers working towards regenerative therapies for spinal cord injury that will help guide future innovation.
Collapse
Affiliation(s)
- Nureddin Ashammakhi
- Division of Plastic Surgery, Department of Surgery, Oulu University, Oulu, Finland.,Center for Minimally Invasive Therapeutics (C-MIT), Los Angeles, California.,California NanoSystems Institute (CNSI), Los Angeles, California.,Department of Radiological Sciences, University of California, Los Angeles, Los Angeles, California.,Department of Bioengineering, University of California, Los Angeles, Los Angeles, California
| | - Han-Jun Kim
- Center for Minimally Invasive Therapeutics (C-MIT), Los Angeles, California.,California NanoSystems Institute (CNSI), Los Angeles, California.,Department of Bioengineering, University of California, Los Angeles, Los Angeles, California
| | | | | | - Outi Kaarela
- Division of Plastic Surgery, Department of Surgery, Oulu University, Oulu, Finland
| | - Chengbin Xue
- Center for Minimally Invasive Therapeutics (C-MIT), Los Angeles, California.,California NanoSystems Institute (CNSI), Los Angeles, California.,Department of Bioengineering, University of California, Los Angeles, Los Angeles, California.,Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, P.R. China.,Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Research Center of Clinical Medicine, Affiliated Hospital of Nantong University, Nantong University, Nantong, P.R. China
| | - Ali Khademhosseini
- Center for Minimally Invasive Therapeutics (C-MIT), Los Angeles, California.,California NanoSystems Institute (CNSI), Los Angeles, California.,Department of Radiological Sciences, University of California, Los Angeles, Los Angeles, California.,Department of Bioengineering, University of California, Los Angeles, Los Angeles, California.,Center of Nanotechnology, King Abdulaziz University, Jeddah, Saudi Arabia.,Department of Chemical and Biological Engineering, University of California, Los Angeles, California
| | - Stephanie K Seidlits
- Center for Minimally Invasive Therapeutics (C-MIT), Los Angeles, California.,California NanoSystems Institute (CNSI), Los Angeles, California.,Jonsson Comprehensive Cancer Center, University of California, Los Angeles, Los Angeles, California.,Broad Stem Cell Research Center, University of California, Los Angeles, Los Angeles, California.,Brain Research Institute, University of California, Los Angeles, Los Angeles, California
| |
Collapse
|
26
|
Metformin-induced AMPK activation stimulates remyelination through induction of neurotrophic factors, downregulation of NogoA and recruitment of Olig2+ precursor cells in the cuprizone murine model of multiple sclerosis. ACTA ACUST UNITED AC 2019; 27:583-592. [PMID: 31620963 DOI: 10.1007/s40199-019-00286-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 06/30/2019] [Indexed: 12/15/2022]
Abstract
PURPOSE Oligodendrocytes (OLGs) damage and myelin distraction is considered as a critical step in many neurological disorders especially multiple sclerosis (MS). Cuprizone (cup) animal model of MS targets OLGs degeneration and frequently used to the mechanistic understanding of de- and remyelination. The aim of this study was exploring the effects of metformin on the OLGs regeneration, myelin repair and profile of neurotrophic factors in the mice brain after cup-induced acute demyelination. METHODS Mice (C57BL/6 J) were fed with chow containing 0.2% cup for 5 weeks to induce specific OLGs degeneration and acute demyelination. Next, the cup was withdrawn to allow one-week recovery (spontaneous remyelination). At the end of this period, mature OLGs markers, myelin-associated neurite outgrowth inhibitor protein A (NogoA), premature specific OLGs transcription factor (Olig2), anti-apoptosis marker (survivin), neurotrophic factors, and AMPK activation were monitored in the presence or absence of metformin (50 mg/kg body weight/day) in the corpus callosum (CC). RESULTS Our finding indicated that consumption of metformin during the recovery period potentially induced an active form of AMPK (p-AMPK) and promoted repopulation of mature OLGs (MOG+ cells, MBP+ cells) in CC through up-regulation of BDNF, CNTF, and NGF as well as down-regulation of NogoA and recruitment of Olig2+ precursor cells. CONCLUSIONS This study for the first time reveals that metformin-induced AMPK, a master regulator of energy homeostasis, activation following toxic demyelination could potentially accelerate regeneration and supports spontaneous demyelination. These findings suggest the development of new therapeutic strategies based on AMPK activation for MS in the near future. Graphical abstract An overview of the possible molecular mechanisms of action of metformin-mediated remyelinationa.
Collapse
|
27
|
Tamoxifen promotes white matter recovery and cognitive functions in male mice after chronic hypoperfusion. Neurochem Int 2019; 131:104566. [PMID: 31593788 DOI: 10.1016/j.neuint.2019.104566] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 09/30/2019] [Accepted: 10/02/2019] [Indexed: 12/18/2022]
Abstract
Cerebral white matter lesions (WMLs) induced by chronic cerebral hypoperfusion are one of the major components of stroke pathology and closely associated with cognitive impairment. However, the repair and related pathophysiology of white matter after brain injury remains relatively elusive and underexplored. Successful neuroregeneration is a method for the potential treatment of central nervous system (CNS) disorders. A non-steroidal estrogen receptor modulator, Tamoxifen, is an effective inhibitor of cell-swelling-activated anion channels and can mimic neuroprotective effects of estrogen in experimental ischemic stroke. However, its remains unclear whether Tamoxifen has beneficial effects in the pathological process after WMLs. In the present study, we investigated the efficacy of Tamoxifen on multiple elements of oligovascular niche of the male C57BL/6 mice brain after bilateral carotid artery stenosis (BCAS) - induced WMLs. Tamoxifen was injected intraperitoneally once daily from 1 day after BCAS until 1 day before sacrificed. Following chronic hypoperfusion, BCAS mice presented white matter demyelination, loss of axon-glia integrity, activated inflammatory response, and cognitive impairments. Tamoxifen treatment significantly facilitated functional restoration of working memory impairment in mice after white matter injury, thus indicating a translational potential for this estrogen receptor modulator given its clinical safety and applicability for WMLs, which lack of currently available treatments. Furthermore, Tamoxifen treatment reduced microglia activation and inflammatory response, favored microglial polarization toward to the M2 phenotype, enhanced oligodendrocyte precursor cells proliferation and differentiation, and promoted remyelination after chronic hypoperfusion. Together, our data indicate that Tamoxifen could alleviate white matter injury and play multiple targets protective effects following chronic hypoperfusion, which is a promising candidate for the therapeutic target for ischemic WMLs and other demyelination diseases associated cognitive impairment.
Collapse
|
28
|
Duncan GJ, Manesh SB, Hilton BJ, Assinck P, Plemel JR, Tetzlaff W. The fate and function of oligodendrocyte progenitor cells after traumatic spinal cord injury. Glia 2019; 68:227-245. [PMID: 31433109 DOI: 10.1002/glia.23706] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 07/24/2019] [Accepted: 08/01/2019] [Indexed: 12/27/2022]
Abstract
Oligodendrocyte progenitor cells (OPCs) are the most proliferative and dispersed population of progenitor cells in the adult central nervous system, which allows these cells to rapidly respond to damage. Oligodendrocytes and myelin are lost after traumatic spinal cord injury (SCI), compromising efficient conduction and, potentially, the long-term health of axons. In response, OPCs proliferate and then differentiate into new oligodendrocytes and Schwann cells to remyelinate axons. This culminates in highly efficient remyelination following experimental SCI in which nearly all intact demyelinated axons are remyelinated in rodent models. However, myelin regeneration comprises only one role of OPCs following SCI. OPCs contribute to scar formation after SCI and restrict the regeneration of injured axons. Moreover, OPCs alter their gene expression following demyelination, express cytokines and perpetuate the immune response. Here, we review the functional contribution of myelin regeneration and other recently uncovered roles of OPCs and their progeny to repair following SCI.
Collapse
Affiliation(s)
- Greg J Duncan
- Department of Neurology, Jungers Center for Neurosciences Research, Oregon Health and Science University, Portland, Oregon
| | - Sohrab B Manesh
- Graduate Program in Neuroscience, International Collaboration on Repair Discoveries (ICORD), University of British Columbia (UBC), Vancouver, British Columbia, Canada
| | - Brett J Hilton
- Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), Bonn, Germany
| | - Peggy Assinck
- MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, UK
| | - Jason R Plemel
- Department of Medicine, Division of Neurology, Neuroscience and Mental Health Institute, University of Alberta, Calgary, Alberta, Canada
| | - Wolfram Tetzlaff
- Graduate Program in Neuroscience, International Collaboration on Repair Discoveries (ICORD), University of British Columbia (UBC), Vancouver, British Columbia, Canada.,Departments of Zoology and Surgery, University of British Columbia, Vancouver, British Columbia, Canada
| |
Collapse
|
29
|
Egawa N, Chung KK, Takahashi R, Lo EH, Inoue H, Arai K. Brief review: Can modulating DNA methylation state help the clinical application of oligodendrocyte precursor cells as a source of stem cell therapy? Brain Res 2019; 1723:146386. [PMID: 31419426 DOI: 10.1016/j.brainres.2019.146386] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 08/08/2019] [Accepted: 08/12/2019] [Indexed: 02/05/2023]
Abstract
Oligodendrocyte precursor cells (OPCs) are one of the major cell types in cerebral white matter, which are generated from neural progenitor cells (NPCs) and give rise to mature oligodendrocytes. Although past studies have extensively examined how OPCs are generated from NPCs and how OPCs differentiate into mature oligodendrocytes, the underlying mechanisms remain unelucidated. In particular, the roles of DNA methylation and the related enzymes DNA methyltransferases (DNMTs) in oligodendrocyte lineage cells are still mostly unknown, although DNA methylation plays a critical role in cell fate decision in multiple cell types. Recently, OPCs were proposed as a promising source of cell-based therapy for patients with oligodendrocyte/myelin damage. Therefore, understanding the mechanisms underlying the involvement of DNMTs in OPCs would help to develop an approach for the efficient preparation of OPCs for cell-based therapy. As a part of the special issue for "Stem Cell Therapy" in Brain Research, this mini-review article first overviews the potential for clinical application of OPCs for cell-based therapy, and then summarizes the key findings of DNMT roles in OPCs, focusing on OPC generation and differentiation.
Collapse
Affiliation(s)
- Naohiro Egawa
- Neuroprotection Research Laboratory, Departments of Radiology and Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Neurology, Kyoto University Graduate School of Medicine, Kyoto, Japan; iPSC-based Drug Discovery and Development Team, RIKEN BioResource Research Center (BRC), Kyoto, Japan; Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, Japan
| | - Kelly K Chung
- Neuroprotection Research Laboratory, Departments of Radiology and Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Ryosuke Takahashi
- Department of Neurology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Eng H Lo
- Neuroprotection Research Laboratory, Departments of Radiology and Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Haruhisa Inoue
- iPSC-based Drug Discovery and Development Team, RIKEN BioResource Research Center (BRC), Kyoto, Japan; Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, Japan; Medical-risk Avoidance Based on iPS Cells Team, RIKEN Center for Advanced Intelligence Project (AIP), Kyoto 606-8507, Japan
| | - Ken Arai
- Neuroprotection Research Laboratory, Departments of Radiology and Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
| |
Collapse
|
30
|
Katoh H, Yokota K, Fehlings MG. Regeneration of Spinal Cord Connectivity Through Stem Cell Transplantation and Biomaterial Scaffolds. Front Cell Neurosci 2019; 13:248. [PMID: 31244609 PMCID: PMC6563678 DOI: 10.3389/fncel.2019.00248] [Citation(s) in RCA: 104] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 05/17/2019] [Indexed: 12/20/2022] Open
Abstract
Significant progress has been made in the treatment of spinal cord injury (SCI). Advances in post-trauma management and intensive rehabilitation have significantly improved the prognosis of SCI and converted what was once an “ailment not to be treated” into a survivable injury, but the cold hard fact is that we still do not have a validated method to improve the paralysis of SCI. The irreversible functional impairment of the injured spinal cord is caused by the disruption of neuronal transduction across the injury lesion, which is brought about by demyelination, axonal degeneration, and loss of synapses. Furthermore, refractory substrates generated in the injured spinal cord inhibit spontaneous recovery. The discovery of the regenerative capability of central nervous system neurons in the proper environment and the verification of neural stem cells in the spinal cord once incited hope that a cure for SCI was on the horizon. That hope was gradually replaced with mounting frustration when neuroprotective drugs, cell transplantation, and strategies to enhance remyelination, axonal regeneration, and neuronal plasticity demonstrated significant improvement in animal models of SCI but did not translate into a cure in human patients. However, recent advances in SCI research have greatly increased our understanding of the fundamental processes underlying SCI and fostered increasing optimism that these multiple treatment strategies are finally coming together to bring about a new era in which we will be able to propose encouraging therapies that will lead to appreciable improvements in SCI patients. In this review, we outline the pathophysiology of SCI that makes the spinal cord refractory to regeneration and discuss the research that has been done with cell replacement and biomaterial implantation strategies, both by itself and as a combined treatment. We will focus on the capacity of these strategies to facilitate the regeneration of neural connectivity necessary to achieve meaningful functional recovery after SCI.
Collapse
Affiliation(s)
- Hiroyuki Katoh
- Division of Genetics and Development, Krembil Research Institute, Toronto, ON, Canada.,Department of Orthopaedic Surgery - Surgical Sciences, School of Medicine, Tokai University, Tokyo, Japan
| | - Kazuya Yokota
- Division of Genetics and Development, Krembil Research Institute, Toronto, ON, Canada.,Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Michael G Fehlings
- Division of Genetics and Development, Krembil Research Institute, Toronto, ON, Canada.,Institute of Medical Science, University of Toronto, Toronto, ON, Canada.,Division of Neurosurgery, University of Toronto, Toronto, ON, Canada.,Spine Program, Toronto Western Hospital, University Health Network, Toronto, ON, Canada
| |
Collapse
|
31
|
Bankston AN, Forston MD, Howard RM, Andres KR, Smith AE, Ohri SS, Bates ML, Bunge MB, Whittemore SR. Autophagy is essential for oligodendrocyte differentiation, survival, and proper myelination. Glia 2019; 67:1745-1759. [PMID: 31162728 DOI: 10.1002/glia.23646] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 05/01/2019] [Accepted: 05/21/2019] [Indexed: 12/12/2022]
Abstract
Deficient myelination, the spiral wrapping of highly specialized membrane around axons, causes severe neurological disorders. Maturation of oligodendrocyte progenitor cells (OPC) to myelinating oligodendrocytes (OL), the sole providers of central nervous system (CNS) myelin, is tightly regulated and involves extensive morphological changes. Here, we present evidence that autophagy, the targeted isolation of cytoplasm and organelles by the double-membrane autophagosome for lysosomal degradation, is essential for OPC/OL differentiation, survival, and proper myelin development. A marked increase in autophagic activity coincides with OL differentiation, with OL processes having the greatest increase in autophagic flux. Multiple lines of evidence indicate that autophagosomes form in developing myelin sheathes before trafficking from myelin to the OL soma. Mice with conditional OPC/OL-specific deletion of the essential autophagy gene Atg5 beginning on postnatal Day 5 develop a rapid tremor and die around postnatal Day 12. Further analysis revealed apoptotic death of OPCs, reduced differentiation, and reduced myelination. Surviving Atg5-/- OLs failed to produce proper myelin structure. In vitro, pharmacological inhibition of autophagy in OPC/dorsal root ganglion (DRG) co-cultures blocked myelination, producing OLs surrounded by many short processes. Conversely, autophagy stimulation enhanced myelination. These results implicate autophagy as a key regulator of OPC survival, maturation, and proper myelination. Autophagy may provide an attractive target to promote both OL survival and subsequent myelin repair after injury.
Collapse
Affiliation(s)
- Andrew N Bankston
- Kentucky Spinal Cord Injury Research Center, University of Louisville School of Medicine, Louisville, Kentucky.,Department of Neurological Surgery, University of Louisville School of Medicine, Louisville, Kentucky
| | - Michael D Forston
- Kentucky Spinal Cord Injury Research Center, University of Louisville School of Medicine, Louisville, Kentucky.,Department of Anatomical Sciences & Neurobiology, University of Louisville School of Medicine, Louisville, Kentucky
| | - Russell M Howard
- Kentucky Spinal Cord Injury Research Center, University of Louisville School of Medicine, Louisville, Kentucky.,Department of Neurological Surgery, University of Louisville School of Medicine, Louisville, Kentucky
| | - Kariena R Andres
- Kentucky Spinal Cord Injury Research Center, University of Louisville School of Medicine, Louisville, Kentucky.,Department of Neurological Surgery, University of Louisville School of Medicine, Louisville, Kentucky
| | - Allison E Smith
- Kentucky Spinal Cord Injury Research Center, University of Louisville School of Medicine, Louisville, Kentucky.,Department of Neurological Surgery, University of Louisville School of Medicine, Louisville, Kentucky
| | - Sujata Saraswat Ohri
- Kentucky Spinal Cord Injury Research Center, University of Louisville School of Medicine, Louisville, Kentucky.,Department of Neurological Surgery, University of Louisville School of Medicine, Louisville, Kentucky
| | - Margaret L Bates
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida
| | - Mary B Bunge
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, Florida.,Department of Cell Biology and Neurological Surgery, University of Miami Miller School of Medicine, Miami, Florida
| | - Scott R Whittemore
- Kentucky Spinal Cord Injury Research Center, University of Louisville School of Medicine, Louisville, Kentucky.,Department of Neurological Surgery, University of Louisville School of Medicine, Louisville, Kentucky.,Department of Anatomical Sciences & Neurobiology, University of Louisville School of Medicine, Louisville, Kentucky
| |
Collapse
|
32
|
Spinal cord injury: pathophysiology, treatment strategies, associated challenges, and future implications. Cell Tissue Res 2019; 377:125-151. [PMID: 31065801 DOI: 10.1007/s00441-019-03039-1] [Citation(s) in RCA: 103] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 04/01/2019] [Indexed: 12/16/2022]
Abstract
Axonal regeneration and formation of tripartite (axo-glial) junctions at damaged sites is a prerequisite for early repair of injured spinal cord. Transplantation of stem cells at such sites of damage which can generate both neuronal and glial population has gained impact in terms of recuperation upon infliction with spinal cord injury. In spite of the fact that a copious number of pre-clinical studies using different stem/progenitor cells have shown promising results at acute and subacute stages, at the chronic stages of injury their recovery rates have shown a drastic decline. Therefore, developing novel therapeutic strategies are the need of the hour in order to assuage secondary morbidity and effectuate improvement of the spinal cord injury (SCI)-afflicted patients' quality of life. The present review aims at providing an overview of the current treatment strategies and also gives an insight into the potential cell-based therapies for the treatment of SCI.
Collapse
|
33
|
Seidlits SK, Liang J, Bierman RD, Sohrabi A, Karam J, Holley SM, Cepeda C, Walthers CM. Peptide-modified, hyaluronic acid-based hydrogels as a 3D culture platform for neural stem/progenitor cell engineering. J Biomed Mater Res A 2019; 107:704-718. [PMID: 30615255 PMCID: PMC8862560 DOI: 10.1002/jbm.a.36603] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 12/23/2018] [Accepted: 01/03/2019] [Indexed: 07/26/2023]
Abstract
Neural stem/progenitor cell (NS/PC)-based therapies have shown exciting potential for regeneration of the central nervous system (CNS) and NS/PC cultures represent an important resource for disease modeling and drug screening. However, significant challenges limiting clinical translation remain, such as generating large numbers of cells required for model cultures or transplantation, maintaining physiologically representative phenotypes ex vivo and directing NS/PC differentiation into specific fates. Here, we report that culture of human NS/PCs in 3D, hyaluronic acid (HA)-rich biomaterial microenvironments increased differentiation toward oligodendrocytes and neurons over 2D cultures on laminin-coated glass. Moreover, NS/PCs in 3D culture exhibited a significant reduction in differentiation into reactive astrocytes. Many NS/PC-derived neurons in 3D, HA-based hydrogels expressed synaptophysin, indicating synapse formation, and displayed electrophysiological characteristics of immature neurons. While inclusion of integrin-binding, RGD peptides into hydrogels resulted in a modest increase in numbers of viable NS/PCs, no combination of laminin-derived, adhesive peptides affected differentiation outcomes. Notably, 3D cultures of differentiating NS/PCs were maintained for at least 70 days in medium with minimal growth factor supplementation. In sum, results demonstrate the use of 3D, HA-based biomaterials for long-term expansion and differentiation of NS/PCs toward oligodendroglial and neuronal fates, while inhibiting astroglial fates. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 704-718, 2019.
Collapse
Affiliation(s)
- Stephanie K. Seidlits
- Department of Bioengineering, UCLA, Los Angels, California
- Board Stem Cell Research Center, UCLA, Los Angels, California
- Brain Research Institute, UCLA, Los Angels, California
- Jonsson Comprehensive Cancer Center, UCLA, Los Angels, California
- Center for Minimally Invasive Therapeutics, UCLA, Los Angels, California
| | - Jesse Liang
- Department of Bioengineering, UCLA, Los Angels, California
| | | | | | - Joshua Karam
- Department of Bioengineering, UCLA, Los Angels, California
| | - Sandra M. Holley
- Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, UCLA, Los Angeles, California
| | - Carlos Cepeda
- Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, UCLA, Los Angeles, California
| | | |
Collapse
|
34
|
Milbreta U, Lin J, Pinese C, Ong W, Chin JS, Shirahama H, Mi R, Williams A, Bechler ME, Wang J, Ffrench-Constant C, Hoke A, Chew SY. Scaffold-Mediated Sustained, Non-viral Delivery of miR-219/miR-338 Promotes CNS Remyelination. Mol Ther 2019; 27:411-423. [PMID: 30611662 PMCID: PMC6369635 DOI: 10.1016/j.ymthe.2018.11.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 11/21/2018] [Accepted: 11/26/2018] [Indexed: 11/20/2022] Open
Abstract
The loss of oligodendrocytes (OLs) and subsequently myelin sheaths following injuries or pathologies in the CNS leads to debilitating functional deficits. Unfortunately, effective methods of remyelination remain limited. Here, we present a scaffolding system that enables sustained non-viral delivery of microRNAs (miRs) to direct OL differentiation, maturation, and myelination. We show that miR-219/miR-338 promoted primary rat OL differentiation and myelination in vitro. Using spinal cord injury as a proof-of-concept, we further demonstrate that miR-219/miR-338 could also be delivered non-virally in vivo using an aligned fiber-hydrogel scaffold to enhance remyelination after a hemi-incision injury at C5 level of Sprague-Dawley rats. Specifically, miR-219/miR-338 mimics were incorporated as complexes with the carrier, TransIT-TKO (TKO), together with neurotrophin-3 (NT-3) within hybrid scaffolds that comprised poly(caprolactone-co-ethyl ethylene phosphate) (PCLEEP)-aligned fibers and collagen hydrogel. After 1, 2, and 4 weeks post-treatment, animals that received NT-3 and miR-219/miR-338 treatment preserved a higher number of Olig2+ oligodendroglial lineage cells as compared with those treated with NT-3 and negative scrambled miRs (Neg miRs; p < 0.001). Additionally, miR-219/miR-338 increased the rate and extent of differentiation of OLs. At the host-implant interface, more compact myelin sheaths were observed when animals received miR-219/miR-338. Similarly within the scaffolds, miR-219/miR-338 samples contained significantly more myelin basic protein (MBP) signals (p < 0.01) and higher myelination index (p < 0.05) than Neg miR samples. These findings highlight the potential of this platform to promote remyelination within the CNS.
Collapse
Affiliation(s)
- Ulla Milbreta
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
| | - Junquan Lin
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
| | - Coline Pinese
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore; Artificial Biopolymers Department, Max Mousseron Institute of Biomolecules (IBMM), UMR CNRS 5247, University of Montpellier, Faculty of Pharmacy, Montpellier 34093, France
| | - William Ong
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore; NTU Institute for Health Technologies (Health Tech NTU), Interdisciplinary Graduate School, Nanyang Technological University, Singapore 637533, Singapore
| | - Jiah Shin Chin
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore; NTU Institute for Health Technologies (Health Tech NTU), Interdisciplinary Graduate School, Nanyang Technological University, Singapore 637533, Singapore
| | - Hitomi Shirahama
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
| | - Ruifa Mi
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Anna Williams
- MRC-Centre for Regenerative Medicine, University of Edinburgh, 5 Little France Drive, Edinburgh EH164UU, Edinburgh, UK
| | - Marie E Bechler
- MRC-Centre for Regenerative Medicine, University of Edinburgh, 5 Little France Drive, Edinburgh EH164UU, Edinburgh, UK
| | - Jun Wang
- China School of Biomedical Science and Engineering, South China University of Technology, Guangzhou International Campus, Guangzhou 510006, P. R. China; National Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou 510006, P. R. China
| | - Charles Ffrench-Constant
- MRC-Centre for Regenerative Medicine, University of Edinburgh, 5 Little France Drive, Edinburgh EH164UU, Edinburgh, UK
| | - Ahmet Hoke
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Sing Yian Chew
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore; Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232, Singapore.
| |
Collapse
|
35
|
Smith DR, Margul DJ, Dumont CM, Carlson MA, Munsell MK, Johnson M, Cummings BJ, Anderson AJ, Shea LD. Combinatorial lentiviral gene delivery of pro-oligodendrogenic factors for improving myelination of regenerating axons after spinal cord injury. Biotechnol Bioeng 2019; 116:155-167. [PMID: 30229864 PMCID: PMC6289889 DOI: 10.1002/bit.26838] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Revised: 08/30/2018] [Accepted: 09/12/2018] [Indexed: 12/12/2022]
Abstract
Spinal cord injury (SCI) results in paralysis below the injury and strategies are being developed that support axonal regrowth, yet recovery lags, in part, because many axons are not remyelinated. Herein, we investigated strategies to increase myelination of regenerating axons by overexpression of platelet-derived growth factor (PDGF)-AA and noggin either alone or in combination in a mouse SCI model. Noggin and PDGF-AA have been identified as factors that enhance recruitment and differentiation of endogenous progenitors to promote myelination. Lentivirus encoding for these factors was delivered from a multichannel bridge, which we have previously shown creates a permissive environment and supports robust axonal growth through channels. The combination of noggin+PDGF enhanced total myelination of regenerating axons relative to either factor alone, and importantly, enhanced functional recovery relative to the control condition. The increase in myelination was consistent with an increase in oligodendrocyte-derived myelin, which was also associated with a greater density of cells of an oligodendroglial lineage relative to each factor individually and control conditions. These results suggest enhanced myelination of regenerating axons by noggin+PDGF that act on oligodendrocyte-lineage cells post-SCI, which ultimately led to improved functional outcomes.
Collapse
Affiliation(s)
- Dominique R. Smith
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Daniel J. Margul
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, USA
| | - Courtney M. Dumont
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Mitchell A. Carlson
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Mary K. Munsell
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Mitchell Johnson
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Brian J. Cummings
- Institute for Memory Impairments and Neurological Disorders (iMIND), University of California, Irvine, CA, USA
- Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, CA, USA
- Department of Anatomy and Neurobiology, University of California, Irvine, CA, USA
- Department of Physical Medicine and Rehabilitation, University of California, Irvine, CA, USA
| | - Aileen J. Anderson
- Institute for Memory Impairments and Neurological Disorders (iMIND), University of California, Irvine, CA, USA
- Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, CA, USA
- Department of Anatomy and Neurobiology, University of California, Irvine, CA, USA
- Department of Physical Medicine and Rehabilitation, University of California, Irvine, CA, USA
| | - Lonnie D. Shea
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI, USA
| |
Collapse
|
36
|
Ashammakhi N, Ahadian S, Darabi MA, El Tahchi M, Lee J, Suthiwanich K, Sheikhi A, Dokmeci MR, Oklu R, Khademhosseini A. Minimally Invasive and Regenerative Therapeutics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1804041. [PMID: 30565732 PMCID: PMC6709364 DOI: 10.1002/adma.201804041] [Citation(s) in RCA: 93] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 08/20/2018] [Indexed: 05/03/2023]
Abstract
Advances in biomaterial synthesis and fabrication, stem cell biology, bioimaging, microsurgery procedures, and microscale technologies have made minimally invasive therapeutics a viable tool in regenerative medicine. Therapeutics, herein defined as cells, biomaterials, biomolecules, and their combinations, can be delivered in a minimally invasive way to regenerate different tissues in the body, such as bone, cartilage, pancreas, cardiac, skeletal muscle, liver, skin, and neural tissues. Sophisticated methods of tracking, sensing, and stimulation of therapeutics in vivo using nano-biomaterials and soft bioelectronic devices provide great opportunities to further develop minimally invasive and regenerative therapeutics (MIRET). In general, minimally invasive delivery methods offer high yield with low risk of complications and reduced costs compared to conventional delivery methods. Here, minimally invasive approaches for delivering regenerative therapeutics into the body are reviewed. The use of MIRET to treat different tissues and organs is described. Although some clinical trials have been performed using MIRET, it is hoped that such therapeutics find wider applications to treat patients. Finally, some future perspective and challenges for this emerging field are highlighted.
Collapse
Affiliation(s)
- Nureddin Ashammakhi
- Center for Minimally Invasive Therapeutics (C-MIT), University of California - Los Angeles, Los Angeles, California, USA
- California NanoSystems Institute (CNSI), University of California - Los Angeles, Los Angeles, California, USA
- Department of Bioengineering, University of California - Los Angeles, Los Angeles, California, USA
- Division of Plastic Surgery, Department of Surgery, Oulu University, Oulu, Finland
| | - Samad Ahadian
- Center for Minimally Invasive Therapeutics (C-MIT), University of California - Los Angeles, Los Angeles, California, USA
- California NanoSystems Institute (CNSI), University of California - Los Angeles, Los Angeles, California, USA
- Department of Bioengineering, University of California - Los Angeles, Los Angeles, California, USA
| | - Mohammad Ali Darabi
- Center for Minimally Invasive Therapeutics (C-MIT), University of California - Los Angeles, Los Angeles, California, USA
- California NanoSystems Institute (CNSI), University of California - Los Angeles, Los Angeles, California, USA
- Department of Bioengineering, University of California - Los Angeles, Los Angeles, California, USA
| | - Mario El Tahchi
- Center for Minimally Invasive Therapeutics (C-MIT), University of California - Los Angeles, Los Angeles, California, USA
- California NanoSystems Institute (CNSI), University of California - Los Angeles, Los Angeles, California, USA
- Department of Bioengineering, University of California - Los Angeles, Los Angeles, California, USA
- LBMI, Department of Physics, Lebanese University - Faculty of Sciences 2, PO Box 90656, Jdeidet, Lebanon
| | - Junmin Lee
- Center for Minimally Invasive Therapeutics (C-MIT), University of California - Los Angeles, Los Angeles, California, USA
- California NanoSystems Institute (CNSI), University of California - Los Angeles, Los Angeles, California, USA
- Department of Bioengineering, University of California - Los Angeles, Los Angeles, California, USA
| | - Kasinan Suthiwanich
- Center for Minimally Invasive Therapeutics (C-MIT), University of California - Los Angeles, Los Angeles, California, USA
- California NanoSystems Institute (CNSI), University of California - Los Angeles, Los Angeles, California, USA
- Department of Bioengineering, University of California - Los Angeles, Los Angeles, California, USA
- Department of Materials Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, Tokyo, Japan
| | - Amir Sheikhi
- Center for Minimally Invasive Therapeutics (C-MIT), University of California - Los Angeles, Los Angeles, California, USA
- California NanoSystems Institute (CNSI), University of California - Los Angeles, Los Angeles, California, USA
- Department of Bioengineering, University of California - Los Angeles, Los Angeles, California, USA
| | - Mehmet R. Dokmeci
- Center for Minimally Invasive Therapeutics (C-MIT), University of California - Los Angeles, Los Angeles, California, USA
- California NanoSystems Institute (CNSI), University of California - Los Angeles, Los Angeles, California, USA
- Department of Bioengineering, University of California - Los Angeles, Los Angeles, California, USA
| | - Rahmi Oklu
- Division of Interventional Radiology, Department of Radiology, Mayo Clinic, Scottsdale, USA
| | - Ali Khademhosseini
- Center for Minimally Invasive Therapeutics (C-MIT), University of California - Los Angeles, Los Angeles, California, USA
- California NanoSystems Institute (CNSI), University of California - Los Angeles, Los Angeles, California, USA
- Department of Bioengineering, University of California - Los Angeles, Los Angeles, California, USA
- Department of Radiological Sciences, University of California - Los Angeles, Los Angeles, California, USA
- Department of Chemical and Biomolecular Engineering, University of California - Los Angeles, Los Angeles, California, USA
- Center of Nanotechnology, Department of Physics, King Abdulaziz University, Jeddah, Saudi Arabia
- Department of Bioindustrial Technologies, College of Animal Bioscience and Technology, Konkuk University, Seoul, Republic of Korea
| |
Collapse
|
37
|
Fu H, Hu D, Zhang L, Shen X, Tang P. Efficacy of Oligodendrocyte Progenitor Cell Transplantation in Rat Models with Traumatic Thoracic Spinal Cord Injury: A Systematic Review and Meta-Analysis. J Neurotrauma 2018; 35:2507-2518. [PMID: 29759026 DOI: 10.1089/neu.2017.5606] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022] Open
Affiliation(s)
- Haitao Fu
- School of Medicine, Nankai University, Tianjin, China
- Department of Orthopedics, the General Hospital of Chinese People's Liberation Army, Beijing, China
| | - Die Hu
- Qingdao Eye Hospital, Shandong Eye Institute, Shandong Academy of Medical Sciences, Qingdao, China
| | - Licheng Zhang
- Department of Orthopedics, the General Hospital of Chinese People's Liberation Army, Beijing, China
| | - Xuezhen Shen
- School of Medicine, Nankai University, Tianjin, China
- Department of Orthopedics, the General Hospital of Chinese People's Liberation Army, Beijing, China
| | - Peifu Tang
- School of Medicine, Nankai University, Tianjin, China
- Department of Orthopedics, the General Hospital of Chinese People's Liberation Army, Beijing, China
| |
Collapse
|
38
|
Cardona SM, Kim SV, Church KA, Torres VO, Cleary IA, Mendiola AS, Saville SP, Watowich SS, Parker-Thornburg J, Soto-Ospina A, Araque P, Ransohoff RM, Cardona AE. Role of the Fractalkine Receptor in CNS Autoimmune Inflammation: New Approach Utilizing a Mouse Model Expressing the Human CX3CR1 I249/M280 Variant. Front Cell Neurosci 2018; 12:365. [PMID: 30386211 PMCID: PMC6199958 DOI: 10.3389/fncel.2018.00365] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 09/26/2018] [Indexed: 12/21/2022] Open
Abstract
Multiple sclerosis (MS), an inflammatory demyelinating disease of the central nervous system (CNS) is the leading cause of non-traumatic neurological disability in young adults. Immune mediated destruction of myelin and oligodendrocytes is considered the primary pathology of MS, but progressive axonal loss is the major cause of neurological disability. In an effort to understand microglia function during CNS inflammation, our laboratory focuses on the fractalkine/CX3CR1 signaling as a regulator of microglia neurotoxicity in various models of neurodegeneration. Fractalkine (FKN) is a transmembrane chemokine expressed in the CNS by neurons and signals through its unique receptor CX3CR1 present in microglia. During experimental autoimmune encephalomyelitis (EAE), CX3CR1 deficiency confers exacerbated disease defined by severe inflammation and neuronal loss. The CX3CR1 human polymorphism I249/M280 present in ∼20% of the population exhibits reduced adhesion for FKN conferring defective signaling whose role in microglia function and influence on neurons during MS remains unsolved. The aim of this study is to assess the effect of weaker signaling through hCX3CR1I249/M280 during EAE. We hypothesize that dysregulated microglial responses due to impaired CX3CR1 signaling enhance neuronal/axonal damage. We generated an animal model replacing the mouse CX3CR1 locus for the hCX3CR1I249/M280 variant. Upon EAE induction, these mice exhibited exacerbated EAE correlating with severe inflammation and neuronal loss. We also observed that mice with aberrant CX3CR1 signaling are unable to produce FKN and ciliary neurotrophic factor during EAE in contrast to wild type mice. Our results provide validation of defective function of the hCX3CR1I249/M280 variant and the foundation to broaden the understanding of microglia dysfunction during neuroinflammation.
Collapse
Affiliation(s)
- Sandra M Cardona
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX, United States.,South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, TX, United States
| | - Sangwon V Kim
- Department of Microbiology and Immunology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, PA, United States
| | - Kaira A Church
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX, United States
| | - Vanessa O Torres
- Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Ian A Cleary
- Department of Biomedical Sciences, Grand Valley State University, Allendale, MI, United States
| | - Andrew S Mendiola
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX, United States.,Gladstone Institute of Neurological Disease, San Francisco, CA, United States
| | - Stephen P Saville
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX, United States.,South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, TX, United States
| | - Stephanie S Watowich
- Department of Immunology, Center for Inflammation and Cancer, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Jan Parker-Thornburg
- Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Alejandro Soto-Ospina
- Basic Sciences Department, Research and Innovation in Chemical Formulations, University EIA, Envigado, Colombia
| | - Pedronel Araque
- Basic Sciences Department, Research and Innovation in Chemical Formulations, University EIA, Envigado, Colombia
| | | | - Astrid E Cardona
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX, United States.,South Texas Center for Emerging Infectious Diseases, The University of Texas at San Antonio, San Antonio, TX, United States
| |
Collapse
|
39
|
Lai B, Feng B, Che M, Wang L, Cai S, Huang M, Gu H, Jiang B, Ling E, Li M, Zeng X, Zeng Y. A Modular Assembly of Spinal Cord-Like Tissue Allows Targeted Tissue Repair in the Transected Spinal Cord. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2018; 5:1800261. [PMID: 30250785 PMCID: PMC6145267 DOI: 10.1002/advs.201800261] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 06/08/2018] [Indexed: 05/02/2023]
Abstract
Tissue engineering-based neural construction holds promise in providing organoids with defined differentiation and therapeutic potentials. Here, a bioengineered transplantable spinal cord-like tissue (SCLT) is assembled in vitro by simulating the white matter and gray matter composition of the spinal cord using neural stem cell-based tissue engineering technique. Whether the organoid would execute targeted repair in injured spinal cord is evaluated. The integrated SCLT, assembled by white matter-like tissue (WMLT) module and gray matter-like tissue (GMLT) module, shares architectural, phenotypic, and functional similarities to the adult rat spinal cord. Organotypic coculturing with the dorsal root ganglion or muscle cells shows that the SCLT embraces spinal cord organogenesis potentials to establish connections with the targets, respectively. Transplantation of the SCLT into the transected spinal cord results in a significant motor function recovery of the paralyzed hind limbs in rats. Additionally, targeted spinal cord tissue repair is achieved by the modular design of SCLT, as evidenced by an increased remyelination in the WMLT area and an enlarged innervation in the GMLT area. More importantly, the pro-regeneration milieu facilitates the formation of a neuronal relay by the donor neurons, allowing the conduction of descending and ascending neural inputs.
Collapse
Affiliation(s)
- Bi‐Qin Lai
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat‐sen University)Ministry of EducationGuangzhou510080China
- Department of Histology and EmbryologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
- Co‐Innovation Center of NeuroregenerationNantong UniversityNantong226001China
| | - Bo Feng
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat‐sen University)Ministry of EducationGuangzhou510080China
| | - Ming‐Tian Che
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat‐sen University)Ministry of EducationGuangzhou510080China
| | - Lai‐Jian Wang
- Guangdong Provincial Key Laboratory of Brain Function and DiseaseZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
| | - Song Cai
- Department of Human AnatomyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
| | - Meng‐Yao Huang
- Guangdong Provincial Key Laboratory of Brain Function and DiseaseZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
| | - Huai‐Yu Gu
- Department of Human AnatomyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
| | - Bing Jiang
- Guangdong Provincial Key Laboratory of Brain Function and DiseaseZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
| | - Eng‐Ang Ling
- Department of AnatomyYong Loo Lin School of MedicineNational University of SingaporeSingapore117594Singapore
| | - Meng Li
- Neuroscience and Mental Health Research InstituteSchool of MedicineCardiff UniversityCardiffCF24 4HQUK
| | - Xiang Zeng
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat‐sen University)Ministry of EducationGuangzhou510080China
- Department of Histology and EmbryologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
- Institute of Spinal Cord InjurySun Yat‐sen UniversityGuangzhou510120China
| | - Yuan‐Shan Zeng
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat‐sen University)Ministry of EducationGuangzhou510080China
- Department of Histology and EmbryologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
- Co‐Innovation Center of NeuroregenerationNantong UniversityNantong226001China
- Guangdong Provincial Key Laboratory of Brain Function and DiseaseZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
- Institute of Spinal Cord InjurySun Yat‐sen UniversityGuangzhou510120China
| |
Collapse
|
40
|
Cortical AAV-CNTF Gene Therapy Combined with Intraspinal Mesenchymal Precursor Cell Transplantation Promotes Functional and Morphological Outcomes after Spinal Cord Injury in Adult Rats. Neural Plast 2018; 2018:9828725. [PMID: 30245710 PMCID: PMC6139201 DOI: 10.1155/2018/9828725] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 04/18/2018] [Accepted: 05/21/2018] [Indexed: 12/11/2022] Open
Abstract
Ciliary neurotrophic factor (CNTF) promotes survival and enhances long-distance regeneration of injured axons in parts of the adult CNS. Here we tested whether CNTF gene therapy targeting corticospinal neurons (CSN) in motor-related regions of the cerebral cortex promotes plasticity and regrowth of axons projecting into the female adult F344 rat spinal cord after moderate thoracic (T10) contusion injury (SCI). Cortical neurons were transduced with a bicistronic adeno-associated viral vector (AAV1) expressing a secretory form of CNTF coupled to mCHERRY (AAV-CNTFmCherry) or with control AAV only (AAV-GFP) two weeks prior to SCI. In some animals, viable or nonviable F344 rat mesenchymal precursor cells (rMPCs) were injected into the lesion site two weeks after SCI to modulate the inhibitory environment. Treatment with AAV-CNTFmCherry, as well as with AAV-CNTFmCherry combined with rMPCs, yielded functional improvements over AAV-GFP alone, as assessed by open-field and Ladderwalk analyses. Cyst size was significantly reduced in the AAV-CNTFmCherry plus viable rMPC treatment group. Cortical injections of biotinylated dextran amine (BDA) revealed more BDA-stained axons rostral and alongside cysts in the AAV-CNTFmCherry versus AAV-GFP groups. After AAV-CNTFmCherry treatments, many sprouting mCherry-immunopositive axons were seen rostral to the SCI, and axons were also occasionally found caudal to the injury site. These data suggest that CNTF has the potential to enhance corticospinal repair by transducing parent CNS populations.
Collapse
|
41
|
Duncan GJ, Manesh SB, Hilton BJ, Assinck P, Liu J, Moulson A, Plemel JR, Tetzlaff W. Locomotor recovery following contusive spinal cord injury does not require oligodendrocyte remyelination. Nat Commun 2018; 9:3066. [PMID: 30076300 PMCID: PMC6076268 DOI: 10.1038/s41467-018-05473-1] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 06/28/2018] [Indexed: 12/16/2022] Open
Abstract
Remyelination occurs after spinal cord injury (SCI) but its functional relevance is unclear. We assessed the necessity of myelin regulatory factor (Myrf) in remyelination after contusive SCI by deleting the gene from platelet-derived growth factor receptor alpha positive (PDGFRα-positive) oligodendrocyte progenitor cells (OPCs) in mice prior to SCI. While OPC proliferation and density are not altered by Myrf inducible knockout after SCI, the accumulation of new oligodendrocytes is largely prevented. This greatly inhibits myelin regeneration, resulting in a 44% reduction in myelinated axons at the lesion epicenter. However, spontaneous locomotor recovery after SCI is not altered by remyelination failure. In controls with functional MYRF, locomotor recovery precedes the onset of most oligodendrocyte myelin regeneration. Collectively, these data demonstrate that MYRF expression in PDGFRα-positive cell derived oligodendrocytes is indispensable for myelin regeneration following contusive SCI but that oligodendrocyte remyelination is not required for spontaneous recovery of stepping.
Collapse
Affiliation(s)
- Greg J Duncan
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia (UBC), 818 West 10th Avenue, V5Z 1M9, Vancouver, BC, Canada
- Department of Zoology, University of British Columbia, 4200-6270 University Blvd, Vancouver, V6T 1Z4, BC, Canada
| | - Sohrab B Manesh
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia (UBC), 818 West 10th Avenue, V5Z 1M9, Vancouver, BC, Canada
- Graduate Program in Neuroscience, University of British Columbia, 3402-2215 Wesbrook Mall, Vancouver, V6T 1Z3, BC, Canada
| | - Brett J Hilton
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia (UBC), 818 West 10th Avenue, V5Z 1M9, Vancouver, BC, Canada
- Department of Zoology, University of British Columbia, 4200-6270 University Blvd, Vancouver, V6T 1Z4, BC, Canada
- Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), Sigmund-Freud-Straße 27, 53127, Bonn, Germany
| | - Peggy Assinck
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia (UBC), 818 West 10th Avenue, V5Z 1M9, Vancouver, BC, Canada
- Graduate Program in Neuroscience, University of British Columbia, 3402-2215 Wesbrook Mall, Vancouver, V6T 1Z3, BC, Canada
| | - Jie Liu
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia (UBC), 818 West 10th Avenue, V5Z 1M9, Vancouver, BC, Canada
| | - Aaron Moulson
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia (UBC), 818 West 10th Avenue, V5Z 1M9, Vancouver, BC, Canada
- Department of Zoology, University of British Columbia, 4200-6270 University Blvd, Vancouver, V6T 1Z4, BC, Canada
| | - Jason R Plemel
- The Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, 3330 Hospital Drive NW, T2N 4N1, Calgary, AB, Canada
| | - Wolfram Tetzlaff
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia (UBC), 818 West 10th Avenue, V5Z 1M9, Vancouver, BC, Canada.
- Department of Zoology, University of British Columbia, 4200-6270 University Blvd, Vancouver, V6T 1Z4, BC, Canada.
- Department of Surgery, University of British Columbia, 2775 Laurel Street, Vancouver, V5Z 1M9, BC, Canada.
| |
Collapse
|
42
|
To Be or Not to Be: Environmental Factors that Drive Myelin Formation during Development and after CNS Trauma. ACTA ACUST UNITED AC 2018. [DOI: 10.3390/neuroglia1010007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Oligodendrocytes are specialized glial cells that myelinate central nervous system (CNS) axons. Historically, it was believed that the primary role of myelin was to compactly ensheath axons, providing the insulation necessary for rapid signal conduction. However, mounting evidence demonstrates the dynamic importance of myelin and oligodendrocytes, including providing metabolic support to neurons and regulating axon protein distribution. As such, the development and maintenance of oligodendrocytes and myelin are integral to preserving CNS homeostasis and supporting proper functioning of widespread neural networks. Environmental signals are critical for proper oligodendrocyte lineage cell progression and their capacity to form functional compact myelin; these signals are markedly disturbed by injury to the CNS, which may compromise endogenous myelin repair capabilities. This review outlines some key environmental factors that drive myelin formation during development and compares that to the primary factors that define a CNS injury milieu. We aim to identify developmental factors disrupted after CNS trauma as well as pathogenic factors that negatively impact oligodendrocyte lineage cells, as these are potential therapeutic targets to promote myelin repair after injury or disease.
Collapse
|
43
|
Dou HC, Chen JY, Ran TF, Jiang WM. Panax quinquefolius saponin inhibits endoplasmic reticulum stress-mediated apoptosis and neurite injury and improves functional recovery in a rat spinal cord injury model. Biomed Pharmacother 2018; 102:212-220. [PMID: 29558718 DOI: 10.1016/j.biopha.2018.03.074] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 03/11/2018] [Accepted: 03/12/2018] [Indexed: 01/13/2023] Open
Abstract
The treatment goal in spinal cord injury (SCI) is to repair neurites and suppress cell apoptosis. Panax quinquefolius saponin (PQS) is the major active ingredient of American ginseng and has been demonstrated to have anti-inflammatory and anti-apoptotic roles in various diseases. However, the potential effect of PQS on the pathological process of acute SCI remains unknown. This work tested the effects of PQS on acute SCI and clarified its potential mechanisms. PQS treatment ameliorated the damage to spinal tissue and improved the functional recovery after SCI. PQS treatment inhibited endoplasmic reticulum (ER) stress and the associated apoptosis after acute SCI. PQS further abolished the triglyceride (TG)-induced ER stress and associated apoptosis in neuronal cultures. PQS appears to inhibit the ER-stress-induced neurite injury in PC12 cells. Our results suggest that PQS is a novel therapeutic agent for acute central nervous system injury.
Collapse
Affiliation(s)
- Hai-Cheng Dou
- Orthopedics Department, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China
| | - Jun-Yu Chen
- Orthopedics Department, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China
| | - Tang-Fei Ran
- Orthopedics Department, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China
| | - Wei-Min Jiang
- Orthopedics Department, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou 215006, China.
| |
Collapse
|
44
|
Thompson R, Sakiyama-Elbert S. Using biomaterials to promote pro-regenerative glial phenotypes after nervous system injuries. ACTA ACUST UNITED AC 2018; 13:024104. [PMID: 29186011 DOI: 10.1088/1748-605x/aa9e23] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Trauma to either the central or peripheral nervous system (PNS) often leads to significant loss of function and disability in patients. This high rate of long-term disability is due to the overall limited regenerative potential of nervous tissue, even though the PNS has more regenerative potential than the central nervous system (CNS). The supporting glial cells in the periphery, Schwann cells, are part of the reason for the improved recovery observed in the PNS. In the CNS, the glial populations, astrocytes and oligodendrocytes (OLs), do not have as much potential to promote regeneration and are at times inhibitory to neuronal growth. In particular, the inhibitory roles astrocytes play following trauma has led to a historical focus on neurons and OLs instead of astrocytes. Recently, this focus has shifted as new, regenerative astrocyte phenotypes have been described. From these observations, glial cells clearly play critical roles in native recovery pathways in both the CNS and PNS. This makes the ability to manipulate both transplanted and native glial cell phenotypes a potentially successful strategy to improve nerve injury outcomes. This review focuses on factors that cause glial cells to adopt repair phenotypes and biomaterials that manipulate and/or harness these glial phenotypes.
Collapse
Affiliation(s)
- Russell Thompson
- Department of Biomedical Engineering, University of Texas at Austin 107 W Dean Keeton, Austin, TX 78712, United States of America. Department of Biomedical Engineering, Washington University in St. Louis, 1 Brooking Drive, St. Louis, MO 63130, United States of America
| | | |
Collapse
|
45
|
FM19G11 and Ependymal Progenitor/Stem Cell Combinatory Treatment Enhances Neuronal Preservation and Oligodendrogenesis after Severe Spinal Cord Injury. Int J Mol Sci 2018; 19:ijms19010200. [PMID: 29315225 PMCID: PMC5796149 DOI: 10.3390/ijms19010200] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Revised: 01/02/2018] [Accepted: 01/05/2018] [Indexed: 01/02/2023] Open
Abstract
Spinal cord injury (SCI) suffers from a lack of effective therapeutic strategies. We have previously shown that individual therapeutic strategies, transplantation of ependymal stem/progenitor cells of the spinal cord after injury (epSPCi) or FM19G11 pharmacological treatment, induce moderate functional recovery after SCI. Here, the combination of treatments has been assayed for functional and histological analysis. Immediately after severe SCI, one million epSPCi were intramedullary injected, and the FM19G11 compound or dimethyl sulfoxide (DMSO) (as the vehicle control) was administrated via intrathecal catheterization. The combination of treatments, epSPCi and FM19G11, improves locomotor tasks compared to the control group, but did not significantly improve the Basso, Beattie, Bresnahan (BBB) scores for locomotor analysis in comparison with the individual treatments. However, the histological analysis of the spinal cord tissues, two months after SCI and treatments, demonstrated that when we treat the animals with both epSPCi and FM19G11, an improved environment for neuronal preservation was generated by reduction of the glial scar extension. The combinatorial treatment also contributes to enhancing the oligodendrocyte precursor cells by inducing the expression of Olig1 in vivo. These results suggest that a combination of therapies may be an exciting new therapeutic treatment for more efficient neuronal activity recovery after severe SCI.
Collapse
|
46
|
Abstract
Neurological injury is the primary lethal mechanism of injury in children, and the primary etiology of long-term disability after trauma. Laboratories and clinical/translational teams have sought to develop stem/progenitor cell therapies to improve recovery in a clinical setting in which there is no significant reparative option. While none of these treatments are currently standard therapeutics, phase IIb clinical trials are underway in both adults and children in severe traumatic brain injury (TBI) and phase I/IIa trials in spinal cord injury. This review will characterize the cell therapy strategies: cell replacement and tissue integration vs. immunomodulation/enhanced endogenous tissue repair. TBI is somewhat different from other central nervous system injuries (spinal cord injury and stroke), in that TBI is a diffuse injury, whereas spinal cord injury and stroke are anatomically discrete. Importantly, this drives cell therapy approaches, as TBI is less apt to be treatable with a local cell replacement intervention. More localized injuries may be more amenable to local approaches and cell replacement to bridge focal gaps. This review focuses on a few reports in the field that highlight areas of progress, but is not intended to be a comprehensive survey of the state of regenerative medicine for neurological injuries.
Collapse
|
47
|
Yang J, Xiong LL, Wang YC, He X, Jiang L, Fu SJ, Han XF, Liu J, Wang TH. Oligodendrocyte precursor cell transplantation promotes functional recovery following contusive spinal cord injury in rats and is associated with altered microRNA expression. Mol Med Rep 2017; 17:771-782. [PMID: 29115639 PMCID: PMC5780154 DOI: 10.3892/mmr.2017.7957] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Accepted: 08/08/2017] [Indexed: 02/05/2023] Open
Abstract
It has been reported that oligodendrocyte precursor cells (OPCs) may be used to treat contusive spinal cord injury (SCC), and may alter microRNA (miRNA/miR) expression following SCC in rats. However, the association between miRNA expression and the treatment of rats with SCC with OPC transplantation remain unclear. The present study transplanted OPCs into the spinal cord of rats with SCC and subsequently used the Basso, Beattie and Bresnahan (BBB) score to assess the functional recovery and pain scores. An miRNA assay was performed to detect differentially expressed miRNAs in the spinal cord of SCC rats transplanted with OPCs, compared with SCC rats transplanted with medium. Quantitative polymerase chain reaction was used to verify significantly altered miRNA expression levels. The results demonstrated that OPC transplantation was able to improve motor recovery and relieve mechanical allodynia in rats with SCC. In addition, through a miRNA assay, 45 differentially expressed miRNAs (40 upregulated miRNAs and 5 downregulated miRNAs) were detected in the spinal cord of rats in the OPC group compared with in the Medium group. Differentially expressed miRNAs were identified according to the following criteria: Fold change >2 and P<0.05. Furthermore, quantitative polymerase chain reaction was used to verify the most highly upregulated (miR‑375‑3p and miR‑1‑3p) and downregulated (miR‑363‑3p, miR‑449a‑5p and miR‑3074) spinal cord miRNAs that were identified in the miRNA assay. In addition, a bioinformatics analysis of these miRNAs indicated that miR‑375 and miR‑1 may act primarily to inhibit cell proliferation and apoptosis via transcriptional and translational regulation, whereas miR‑363, miR‑449a and miR‑3074 may act primarily to inhibit cell proliferation and neuronal differentiation through transcriptional regulation. These results suggested that OPC transplantation may promote functional recovery of rats with SCC, which may be associated with the expression of various miRNAs in the spinal cord, including miR‑375‑3p, miR‑1‑3p, miR‑363‑3p, miR‑449a‑5p and miR‑3074.
Collapse
Affiliation(s)
- Jin Yang
- Institute of Neuroscience, College of Basic Medicine, Kunming Medical University, Kunming, Yunnan 650500, P.R. China
| | - Liu-Lin Xiong
- Department of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - You-Cui Wang
- Institute of Neurobiological Disease, State Key Laboratory of Biotherapy, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Xiang He
- Department of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Ling Jiang
- Department of Anesthesia and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Song-Jun Fu
- Institute of Neuroscience, College of Basic Medicine, Kunming Medical University, Kunming, Yunnan 650500, P.R. China
| | - Xue-Fei Han
- Institute of Neuroscience, College of Basic Medicine, Kunming Medical University, Kunming, Yunnan 650500, P.R. China
| | - Jia Liu
- Experimental Animal Center, Kunming Medical University, Kunming, Yunnan 650500, P.R. China
| | - Ting-Hua Wang
- Institute of Neuroscience, College of Basic Medicine, Kunming Medical University, Kunming, Yunnan 650500, P.R. China
| |
Collapse
|
48
|
Zhou Y, Wang Z, Li J, Li X, Xiao J. Fibroblast growth factors in the management of spinal cord injury. J Cell Mol Med 2017; 22:25-37. [PMID: 29063730 PMCID: PMC5742738 DOI: 10.1111/jcmm.13353] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 07/12/2017] [Indexed: 12/11/2022] Open
Abstract
Spinal cord injury (SCI) possesses a significant health and economic burden worldwide. Traumatic SCI is a devastating condition that evolves through two successive stages. Throughout each of these stages, disturbances in ionic homeostasis, local oedema, ischaemia, focal haemorrhage, free radicals stress and inflammatory response were observed. Although there are no fully restorative cures available for SCI patients, various molecular, cellular and rehabilitative therapies, such as limiting local inflammation, preventing secondary cell death and enhancing the plasticity of local circuits in the spinal cord, were described. Current preclinical studies have showed that fibroblast growth factors (FGFs) alone or combination therapies utilizing cell transplantation and biomaterial scaffolds are proven effective for treating SCI in animal models. More importantly, some studies further demonstrated a paucity of clinical transfer usage to promote functional recovery of numerous patients with SCI. In this review, we focus on the therapeutic capacity and pitfalls of the FGF family and its clinical application for treating SCI, including the signalling component of the FGF pathway and the role in the central nervous system, the pathophysiology of SCI and the targets for FGF treatment. We also discuss the challenges and potential for the clinical translation of FGF-based approaches into treatments for SCI.
Collapse
Affiliation(s)
- Yulong Zhou
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China.,Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Zhouguang Wang
- Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jiawei Li
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China.,Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xiaokun Li
- Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jian Xiao
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China.,Molecular Pharmacology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, China
| |
Collapse
|
49
|
Yao L, Li Y. The Role of Direct Current Electric Field-Guided Stem Cell Migration in Neural Regeneration. Stem Cell Rev Rep 2017; 12:365-75. [PMID: 27108005 DOI: 10.1007/s12015-016-9654-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Effective directional axonal growth and neural cell migration are crucial in the neural regeneration of the central nervous system (CNS). Endogenous currents have been detected in many developing nervous systems. Experiments have demonstrated that applied direct current (DC) electric fields (EFs) can guide axonal growth in vitro, and attempts have been made to enhance the regrowth of damaged spinal cord axons using DC EFs in in vivo experiments. Recent work has revealed that the migration of stem cells and stem cell-derived neural cells can be guided by DC EFs. These studies have raised the possibility that endogenous and applied DC EFs can be used to direct neural tissue regeneration. Although the mechanism of EF-directed axonal growth and cell migration has not been fully understood, studies have shown that the polarization of cell membrane proteins and the activation of intracellular signaling molecules are involved in the process. The application of EFs is a promising biotechnology for regeneration of the CNS.
Collapse
Affiliation(s)
- Li Yao
- Department of Biological Sciences, Wichita State University, Wichita, KS, 67260, USA.
| | - Yongchao Li
- Department of Biological Sciences, Wichita State University, Wichita, KS, 67260, USA
| |
Collapse
|
50
|
Myelinogenic Plasticity of Oligodendrocyte Precursor Cells following Spinal Cord Contusion Injury. J Neurosci 2017; 37:8635-8654. [PMID: 28760862 DOI: 10.1523/jneurosci.2409-16.2017] [Citation(s) in RCA: 92] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 06/22/2017] [Accepted: 07/22/2017] [Indexed: 12/17/2022] Open
Abstract
Spontaneous remyelination occurs after spinal cord injury (SCI), but the extent of myelin repair and identity of the cells responsible remain incompletely understood and contentious. We assessed the cellular origin of new myelin by fate mapping platelet-derived growth factor receptor α (PDGFRα), Olig2+, and P0+ cells following contusion SCI in mice. Oligodendrocyte precursor cells (OPCs; PDGFRα+) produced oligodendrocytes responsible for de novo ensheathment of ∼30% of myelinated spinal axons at injury epicenter 3 months after SCI, demonstrating that these resident cells are a major contributor to oligodendrocyte regeneration. OPCs also produced the majority of myelinating Schwann cells in the injured spinal cord; invasion of peripheral myelinating (P0+) Schwann cells made only a limited contribution. These findings reveal that PDGFRα+ cells perform diverse roles in CNS repair, as multipotential progenitors that generate both classes of myelinating cells. This endogenous repair might be exploited as a therapeutic target for CNS trauma and disease.SIGNIFICANCE STATEMENT Spinal cord injury (SCI) leads to profound functional deficits, though substantial numbers of axons often survive. One possible explanation for these deficits is loss of myelin, creating conduction block at the site of injury. SCI leads to oligodendrocyte death and demyelination, and clinical trials have tested glial transplants to promote myelin repair. However, the degree and duration of myelin loss, and the extent and mechanisms of endogenous repair, have been contentious issues. Here, we use genetic fate mapping to demonstrate that spontaneous myelin repair by endogenous oligodendrocyte precursors is much more robust than previously recognized. These findings are relevant to many types of CNS pathology, raising the possibility that CNS precursors could be manipulated to repair myelin in lieu of glial transplantation.
Collapse
|