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Mirkiani S, O’Sullivan CL, Roszko DA, Faridi P, Hu DS, Everaert DG, Toossi A, Kang R, Fang T, Tyreman N, Dalrymple AN, Robinson K, Uwiera RRE, Shah H, Fox R, Konrad PE, Mushahwar VK. Safety of mapping the motor networks in the spinal cord using penetrating microelectrodes in Yucatan minipigs. J Neurosurg Spine 2024; 41:292-304. [PMID: 38728765 PMCID: PMC11174925 DOI: 10.3171/2024.2.spine23757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Accepted: 02/21/2024] [Indexed: 05/12/2024]
Abstract
OBJECTIVE The goal of this study was to assess the safety of mapping spinal cord locomotor networks using penetrating stimulation microelectrodes in Yucatan minipigs (YMPs) as a clinically translational animal model. METHODS Eleven YMPs were trained to walk up and down a straight line. Motion capture was performed, and electromyographic (EMG) activity of hindlimb muscles was recorded during overground walking. The YMPs underwent a laminectomy and durotomy to expose the lumbar spinal cord. Using an ultrasound-guided stereotaxic frame, microelectrodes were inserted into the spinal cord in 8 animals. Pial cuts were made to prevent tissue dimpling before microelectrode insertion. Different locations within the lumbar enlargement were electrically stimulated to map the locomotor networks. The remaining 3 YMPs served as sham controls, receiving the laminectomy, durotomy, and pial cuts but not microelectrode insertion. The Porcine Thoracic Injury Behavioral Scale (PTIBS) and hindlimb reflex assessment results were recorded for 4 weeks postoperatively. Overground gait kinematics and hindlimb EMG activity were recorded again at weeks 3 and 4 postoperatively and compared with preoperative measures. The animals were euthanized at the end of week 4, and the lumbar spinal cords were extracted and preserved for immunohistochemical analysis. RESULTS All YMPs showed transient deficits in hindlimb function postoperatively. Except for 1 YMP in the experimental group, all animals regained normal ambulation and balance (PTIBS score 10) at the end of weeks 3 and 4. One animal in the experimental group showed gait and balance deficits by week 4 (PTIBS score 4). This animal was excluded from the kinematics and EMG analyses. Overground gait kinematic measures and EMG activity showed no significant (p > 0.05) differences between preoperative and postoperative values, and between the experimental and sham groups. Less than 5% of electrode tracks were visible in the tissue analysis of the animals in the experimental group. There was no statistically significant difference in damage caused by pial cuts between the experimental and sham groups. Tissue damage due to the pial cuts was more frequently observed in immunohistochemical analyses than microelectrode tracks. CONCLUSIONS These findings suggest that mapping spinal locomotor networks in porcine models can be performed safely, without lasting damage to the spinal cord.
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Affiliation(s)
- Soroush Mirkiani
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
- Institute for Augmentative and Restorative Technologies and Health Innovations (iSMART), University of Alberta, Edmonton, Alberta, Canada
| | - Carly L. O’Sullivan
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
- Institute for Augmentative and Restorative Technologies and Health Innovations (iSMART), University of Alberta, Edmonton, Alberta, Canada
| | - David A. Roszko
- Institute for Augmentative and Restorative Technologies and Health Innovations (iSMART), University of Alberta, Edmonton, Alberta, Canada
- Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Ontario, Canada
| | - Pouria Faridi
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
- Institute for Augmentative and Restorative Technologies and Health Innovations (iSMART), University of Alberta, Edmonton, Alberta, Canada
| | - David S. Hu
- Institute for Augmentative and Restorative Technologies and Health Innovations (iSMART), University of Alberta, Edmonton, Alberta, Canada
- Division of Physical Medicine and Rehabilitation, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Dirk G. Everaert
- Institute for Augmentative and Restorative Technologies and Health Innovations (iSMART), University of Alberta, Edmonton, Alberta, Canada
- Division of Physical Medicine and Rehabilitation, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Amirali Toossi
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
- Institute for Augmentative and Restorative Technologies and Health Innovations (iSMART), University of Alberta, Edmonton, Alberta, Canada
- Division of Physical Medicine and Rehabilitation, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Ryan Kang
- Institute for Augmentative and Restorative Technologies and Health Innovations (iSMART), University of Alberta, Edmonton, Alberta, Canada
| | - Tongzhou Fang
- Institute for Augmentative and Restorative Technologies and Health Innovations (iSMART), University of Alberta, Edmonton, Alberta, Canada
| | - Neil Tyreman
- Institute for Augmentative and Restorative Technologies and Health Innovations (iSMART), University of Alberta, Edmonton, Alberta, Canada
- Division of Physical Medicine and Rehabilitation, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Ashley N. Dalrymple
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
- Institute for Augmentative and Restorative Technologies and Health Innovations (iSMART), University of Alberta, Edmonton, Alberta, Canada
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania
| | - Kevin Robinson
- School of Physical Therapy, Belmont University, Nashville, Tennessee
| | - Richard R. E. Uwiera
- Institute for Augmentative and Restorative Technologies and Health Innovations (iSMART), University of Alberta, Edmonton, Alberta, Canada
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Hamid Shah
- Vanderbilt University Medical Center, Nashville, Tennessee
| | - Richard Fox
- Institute for Augmentative and Restorative Technologies and Health Innovations (iSMART), University of Alberta, Edmonton, Alberta, Canada
- Division of Neurosurgery, Department of Surgery, University of Alberta, Edmonton, Alberta, Canada
| | - Peter E. Konrad
- Department of Neurosurgery, West Virginia University, Morgantown, West Virginia; and
- Integrative Neuroscience & Clinical Innovation, Rockefeller Neuroscience Institute, Morgantown, West Virginia
| | - Vivian K. Mushahwar
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
- Institute for Augmentative and Restorative Technologies and Health Innovations (iSMART), University of Alberta, Edmonton, Alberta, Canada
- Division of Physical Medicine and Rehabilitation, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada
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2
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Smith AC, Ahmed RU, Weber KA, Negahdar M, Gibson D, Boakye M, Rejc E. Spinal cord lesion MRI and behavioral outcomes in a miniature pig model of spinal cord injury: exploring preclinical potential through an ad hoc comparison with human SCI. Spinal Cord Ser Cases 2024; 10:44. [PMID: 38977671 PMCID: PMC11231227 DOI: 10.1038/s41394-024-00658-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 06/24/2024] [Accepted: 07/02/2024] [Indexed: 07/10/2024] Open
Abstract
STUDY DESIGN prospective case series of Yucatan miniature pig spinal cord contusion injury model with comparison to human cases of spinal cord injury (SCI). OBJECTIVES to describe magnetic resonance imaging (MRI) measures of spinal cord lesion severity along with estimates of lateral corticospinal tracts spared neural tissue in both a less severe and more severe contusion SCI model, as well as to describe their corresponding behavioral outcome changes. SETTING University laboratory setting. METHODS Following a more severe and less severe SCI, each pig underwent spinal cord MRI to measure lesion characteristics, along with locomotor and urodynamics outcomes testing. RESULTS In the pig with more severe SCI, locomotor and urodynamic outcomes were poor, and both the spinal cord lesion volume and damage estimates to the lateral corticospinal tracts were large. Conversely, in the pig with less severe SCI, locomotor and urodynamic outcomes were favorable, with the spinal cord lesion volume and damage estimates to the lateral corticospinal tracts being less pronounced. For two human cases matched on estimates of damage to the lateral corticospinal tract regions, the clinical presentations were similar to the pig outcomes, with more limited mobility and more limited bladder functional independence in the more severe case. CONCLUSIONS Our initial findings contribute valuable insights to the emergent field of MRI-based evaluation of spinal cord lesions in pig models, offering a promising avenue for understanding and potentially improving outcomes in spinal cord injuries.
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Affiliation(s)
- Andrew C Smith
- University of Colorado School of Medicine, Department of Physical Medicine and Rehabilitation, Aurora, CO, USA.
| | - Rakib Uddin Ahmed
- University of Louisville School of Medicine, Department of Neurosurgery, Louisville, KY, USA
| | - Kenneth A Weber
- Stanford University School of Medicine, Department of Anesthesiology, Perioperative and Pain Medicine, Palo Alto, CA, USA
| | - MohammadJavad Negahdar
- University of Louisville School of Medicine, Department of Radiology, Louisville, KY, USA
| | - Destiny Gibson
- University of Louisville School of Medicine, Department of Neurosurgery, Louisville, KY, USA
| | - Maxwell Boakye
- University of Louisville School of Medicine, Department of Neurosurgery, Louisville, KY, USA
| | - Enrico Rejc
- University of Udine, Department of Medicine, Udine, Italy
- Kessler Foundation, West Orange, NJ, USA
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3
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Wathen CA, Ghenbot YG, Ozturk AK, Cullen DK, O’Donnell JC, Petrov D. Porcine Models of Spinal Cord Injury. Biomedicines 2023; 11:2202. [PMID: 37626699 PMCID: PMC10452184 DOI: 10.3390/biomedicines11082202] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 07/23/2023] [Accepted: 07/29/2023] [Indexed: 08/27/2023] Open
Abstract
Large animal models of spinal cord injury may be useful tools in facilitating the development of translational therapies for spinal cord injury (SCI). Porcine models of SCI are of particular interest due to significant anatomic and physiologic similarities to humans. The similar size and functional organization of the porcine spinal cord, for instance, may facilitate more accurate evaluation of axonal regeneration across long distances that more closely resemble the realities of clinical SCI. Furthermore, the porcine cardiovascular system closely resembles that of humans, including at the level of the spinal cord vascular supply. These anatomic and physiologic similarities to humans not only enable more representative SCI models with the ability to accurately evaluate the translational potential of novel therapies, especially biologics, they also facilitate the collection of physiologic data to assess response to therapy in a setting similar to those used in the clinical management of SCI. This review summarizes the current landscape of porcine spinal cord injury research, including the available models, outcome measures, and the strengths, limitations, and alternatives to porcine models. As the number of investigational SCI therapies grow, porcine SCI models provide an attractive platform for the evaluation of promising treatments prior to clinical translation.
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Affiliation(s)
- Connor A. Wathen
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; (C.A.W.); (Y.G.G.); (A.K.O.); (D.K.C.); (J.C.O.)
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA 19104, USA
| | - Yohannes G. Ghenbot
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; (C.A.W.); (Y.G.G.); (A.K.O.); (D.K.C.); (J.C.O.)
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA 19104, USA
| | - Ali K. Ozturk
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; (C.A.W.); (Y.G.G.); (A.K.O.); (D.K.C.); (J.C.O.)
| | - D. Kacy Cullen
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; (C.A.W.); (Y.G.G.); (A.K.O.); (D.K.C.); (J.C.O.)
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA 19104, USA
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - John C. O’Donnell
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; (C.A.W.); (Y.G.G.); (A.K.O.); (D.K.C.); (J.C.O.)
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA 19104, USA
| | - Dmitriy Petrov
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; (C.A.W.); (Y.G.G.); (A.K.O.); (D.K.C.); (J.C.O.)
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Knibbe CA, Ahmed RU, Wilkins F, Sharma M, Ethridge J, Morgan M, Gibson D, Cooper KB, Howland DR, Vadhanam MV, Barve SS, Davison S, Sherwood LC, Semler J, Abell T, Boakye M. SmartPill™ Administration to Assess Gastrointestinal Function after Spinal Cord Injury in a Porcine Model-A Preliminary Study. Biomedicines 2023; 11:1660. [PMID: 37371755 DOI: 10.3390/biomedicines11061660] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 06/02/2023] [Accepted: 06/04/2023] [Indexed: 06/29/2023] Open
Abstract
Gastrointestinal (GI) complications, including motility disorders, metabolic deficiencies, and changes in gut microbiota following spinal cord injury (SCI), are associated with poor outcomes. After SCI, the autonomic nervous system becomes unbalanced below the level of injury and can lead to severe GI dysfunction. The SmartPill™ is a non-invasive capsule that, when ingested, transmits pH, temperature, and pressure readings that can be used to assess effects in GI function post-injury. Our minipig model allows us to assess these post-injury changes to optimize interventions and ultimately improve GI function. The aim of this study was to compare pre-injury to post-injury transit times, pH, and pressures in sections of GI tract by utilizing the SmartPill™ in three pigs after SCI at 2 and 6 weeks. Tributyrin was administered to two pigs to assess the influences on their gut microenvironment. We observed prolonged GET (Gastric Emptying Time) and CTT (Colon Transit Time), decreases in contraction frequencies (Con freq) in the antrum of the stomach, colon, and decreases in duodenal pressures post-injury. We noted increases in Sum amp generated at 2 weeks post-injury in the colon, with corresponding decreases in Con freq. We found transient changes in pH in the colon and small intestine at 2 weeks post-injury, with minimal effect on stomach pH post-injury. Prolonged GETs and CTTs can influence the absorptive profile in the gut and contribute to pathology development. This is the first pilot study to administer the SmartPill™ in minipigs in the context of SCI. Further investigations will elucidate these trends and characterize post-SCI GI function.
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Affiliation(s)
- Chase A Knibbe
- Department of Neurological Surgery, Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY 40202, USA
| | - Rakib Uddin Ahmed
- Department of Neurological Surgery, Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY 40202, USA
| | - Felicia Wilkins
- Department of Neurological Surgery, Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY 40202, USA
| | - Mayur Sharma
- Department of Neurological Surgery, Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY 40202, USA
| | - Jay Ethridge
- Department of Neurological Surgery, Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY 40202, USA
| | - Monique Morgan
- Department of Neurological Surgery, Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY 40202, USA
| | - Destiny Gibson
- Department of Neurological Surgery, Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY 40202, USA
| | - Kimberly B Cooper
- Department of Neurological Surgery, Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY 40202, USA
| | - Dena R Howland
- Department of Neurological Surgery, Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY 40202, USA
- Research Service, Robley Rex Veterans Affairs Medical Center, Louisville, KY 40206, USA
| | - Manicka V Vadhanam
- Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, University of Louisville, Louisville, KY 40202, USA
| | - Shirish S Barve
- Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, University of Louisville, Louisville, KY 40202, USA
| | - Steven Davison
- Comparative Medicine Research Unit, University of Louisville, Louisville, KY 40202, USA
| | - Leslie C Sherwood
- Comparative Medicine Research Unit, University of Louisville, Louisville, KY 40202, USA
| | | | - Thomas Abell
- Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, University of Louisville, Louisville, KY 40202, USA
| | - Maxwell Boakye
- Department of Neurological Surgery, Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY 40202, USA
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5
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Shulman I, Ageeva T, Kostennikov A, Ogurcov S, Tazetdinova L, Kabdesh I, Rogozhin A, Ganiev I, Rizvanov A, Mukhamedshina Y. Intrathecal Injection of Autologous Mesenchymal Stem-Cell-Derived Extracellular Vesicles in Spinal Cord Injury: A Feasibility Study in Pigs. Int J Mol Sci 2023; 24:ijms24098240. [PMID: 37175946 PMCID: PMC10179045 DOI: 10.3390/ijms24098240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 04/24/2023] [Accepted: 04/27/2023] [Indexed: 05/15/2023] Open
Abstract
Spinal cord injury (SCI) remains one of the current medical and social problems, as it causes deep disability in patients. The use of mesenchymal stem cell (MSC)-derived extracellular vesicles (EVs) is one strategy for stimulating the post-traumatic recovery of the structure and function of the spinal cord. Here, we chose an optimal method for obtaining cytochalasin B-induced EVs, including steps with active vortex mixing for 60 s and subsequent filtration to remove nuclei and disorganized inclusions. The therapeutic potential of repeated intrathecal injection of autologous MSC-derived EVs in the subacute period of pig contused SCI was also evaluated for the first time. In this study, we observed the partial restoration of locomotor activity by stimulating the remyelination of axons and timely reperfusion of nervous tissue.
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Affiliation(s)
- Ilya Shulman
- Neurosurgical Department No. 2, Republic Clinical Hospital, 420138 Kazan, Russia
| | - Tatyana Ageeva
- Center for Clinical Research for Precision and Regenerative Medicine, Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia
| | - Alexander Kostennikov
- Center for Clinical Research for Precision and Regenerative Medicine, Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia
| | - Sergei Ogurcov
- Neurosurgical Department No. 2, Republic Clinical Hospital, 420138 Kazan, Russia
| | - Leysan Tazetdinova
- Department of Morphology and General Pathology, Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia
| | - Ilyas Kabdesh
- Center for Clinical Research for Precision and Regenerative Medicine, Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia
| | - Alexander Rogozhin
- Department of Neurology, Kazan State Medical Academy-Branch Campus of the Federal State Budgetary Educational Institution of Father Professional Education, Russian Medical Academy of Continuous Professional Education, 420012 Kazan, Russia
| | - Ilnur Ganiev
- Scientific and Educational Center of Pharmacy, Kazan Federal University, 420008 Kazan, Russia
| | - Albert Rizvanov
- Center for Clinical Research for Precision and Regenerative Medicine, Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia
| | - Yana Mukhamedshina
- Center for Clinical Research for Precision and Regenerative Medicine, Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia
- Department of Histology, Cytology and Embryology, Kazan State Medical University, 420012 Kazan, Russia
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6
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Dorrian RM, Berryman CF, Lauto A, Leonard AV. Electrical stimulation for the treatment of spinal cord injuries: A review of the cellular and molecular mechanisms that drive functional improvements. Front Cell Neurosci 2023; 17:1095259. [PMID: 36816852 PMCID: PMC9936196 DOI: 10.3389/fncel.2023.1095259] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 01/16/2023] [Indexed: 02/05/2023] Open
Abstract
Spinal cord injury (SCI) is a devastating condition that causes severe loss of motor, sensory and autonomic functions. Additionally, many individuals experience chronic neuropathic pain that is often refractory to interventions. While treatment options to improve outcomes for individuals with SCI remain limited, significant research efforts in the field of electrical stimulation have made promising advancements. Epidural electrical stimulation, peripheral nerve stimulation, and functional electrical stimulation have shown promising improvements for individuals with SCI, ranging from complete weight-bearing locomotion to the recovery of sexual function. Despite this, there is a paucity of mechanistic understanding, limiting our ability to optimize stimulation devices and parameters, or utilize combinatorial treatments to maximize efficacy. This review provides a background into SCI pathophysiology and electrical stimulation methods, before exploring cellular and molecular mechanisms suggested in the literature. We highlight several key mechanisms that contribute to functional improvements from electrical stimulation, identify gaps in current knowledge and highlight potential research avenues for future studies.
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Affiliation(s)
- Ryan M. Dorrian
- Spinal Cord Injury Research Group, School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia,*Correspondence: Ryan M. Dorrian,
| | | | - Antonio Lauto
- School of Science, Western Sydney University, Penrith, NSW, Australia
| | - Anna V. Leonard
- Spinal Cord Injury Research Group, School of Biomedicine, The University of Adelaide, Adelaide, SA, Australia
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7
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Malomo T, Allard Brown A, Bale K, Yung A, Kozlowski P, Heran M, Streijger F, Kwon BK. Quantifying Intraparenchymal Hemorrhage after Traumatic Spinal Cord Injury: A Review of Methodology. J Neurotrauma 2022; 39:1603-1635. [PMID: 35538847 DOI: 10.1089/neu.2021.0317] [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: 01/06/2023] Open
Abstract
Intraparenchymal hemorrhage (IPH) after a traumatic injury has been associated with poor neurological outcomes. Although IPH may result from the initial mechanical trauma, the blood and its breakdown products have potentially deleterious effects. Further, the degree of IPH has been correlated with injury severity and the extent of subsequent recovery. Therefore, accurate evaluation and quantification of IPH following traumatic spinal cord injury (SCI) is important to define treatments' effects on IPH progression and secondary neuronal injury. Imaging modalities, such as magnetic resonance imaging (MRI) and ultrasound (US), have been explored by researchers for the detection and quantification of IPH following SCI. Both quantitative and semiquantitative MRI and US measurements have been applied to objectively assess IPH following SCI, but the optimal methods for doing so are not well established. Studies in animal SCI models (rodent and porcine) have explored US and histological techniques in evaluating SCI and have demonstrated the potential to detect and quantify IPH. Newer techniques using machine learning algorithms (such as convolutional neural networks [CNN]) have also been studied to calculate IPH volume and have yielded promising results. Despite long-standing recognition of the potential pathological significance of IPH within the spinal cord, quantifying IPH with MRI or US is a relatively new area of research. Further studies are warranted to investigate their potential use. Here, we review the different and emerging quantitative MRI, US, and histological approaches used to detect and quantify IPH following SCI.
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Affiliation(s)
- Toluyemi Malomo
- International Collaboration on Repair Discoveries, Division of Neuroradiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Aysha Allard Brown
- International Collaboration on Repair Discoveries, Division of Neuroradiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kirsten Bale
- International Collaboration on Repair Discoveries, Division of Neuroradiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada.,UBC MRI Research Center, Division of Neuroradiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Andrew Yung
- International Collaboration on Repair Discoveries, Division of Neuroradiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada.,UBC MRI Research Center, Division of Neuroradiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Piotr Kozlowski
- International Collaboration on Repair Discoveries, Division of Neuroradiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada.,UBC MRI Research Center, Division of Neuroradiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Manraj Heran
- Department of Radiology, Division of Neuroradiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Femke Streijger
- International Collaboration on Repair Discoveries, Division of Neuroradiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Brian K Kwon
- International Collaboration on Repair Discoveries, Division of Neuroradiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada.,Vancouver Spine Surgery Institute, Department of Orthopaedics, and Division of Neuroradiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada
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8
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Weber-Levine C, Hersh AM, Jiang K, Routkevitch D, Tsehay Y, Perdomo-Pantoja A, Judy BF, Kerensky M, Liu A, Adams M, Izzi J, Doloff JC, Manbachi A, Theodore N. Porcine Model of Spinal Cord Injury: A Systematic Review. Neurotrauma Rep 2022; 3:352-368. [PMID: 36204385 PMCID: PMC9531891 DOI: 10.1089/neur.2022.0038] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Spinal cord injury (SCI) is a devastating disease with limited effective treatment options. Animal paradigms are vital for understanding the pathogenesis of SCI and testing potential therapeutics. The porcine model of SCI is increasingly favored because of its greater similarity to humans. However, its adoption is limited by the complexities of care and range of testing parameters. Researchers need to consider swine selection, injury method, post-operative care, rehabilitation, behavioral outcomes, and histology metrics. Therefore, we systematically reviewed full-text English-language articles to evaluate study characteristics used in developing a porcine model and summarize the interventions that have been tested using this paradigm. A total of 63 studies were included, with 33 examining SCI pathogenesis and 30 testing interventions. Studies had an average sample size of 15 pigs with an average weight of 26 kg, and most used female swine with injury to the thoracic cord. Injury was most commonly induced by weight drop with compression. The porcine model is amenable to testing various interventions, including mean arterial pressure augmentation (n = 7), electrical stimulation (n = 6), stem cell therapy (n = 5), hypothermia (n = 2), biomaterials (n = 2), gene therapy (n = 2), steroids (n = 1), and nanoparticles (n = 1). It is also notable for its clinical translatability and is emerging as a valuable pre-clinical study tool. This systematic review can serve as a guideline for researchers implementing and testing the porcine SCI model.
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Affiliation(s)
- Carly Weber-Levine
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Andrew M. Hersh
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Kelly Jiang
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Denis Routkevitch
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Yohannes Tsehay
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | | | - Brendan F. Judy
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Max Kerensky
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Ann Liu
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Melanie Adams
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jessica Izzi
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Joshua C. Doloff
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Amir Manbachi
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Nicholas Theodore
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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9
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Doelman A, Tigchelaar S, McConeghy B, Sinha S, Keung MS, Manouchehri N, Webster M, Fisk S, Morrison C, Streijger F, Nislow C, Kwon BK. Characterization of the gut microbiome in a porcine model of thoracic spinal cord injury. BMC Genomics 2021; 22:775. [PMID: 34717545 PMCID: PMC8557039 DOI: 10.1186/s12864-021-07979-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 09/01/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND The gut microbiome is a diverse network of bacteria which inhabit our digestive tract and is crucial for efficient cellular metabolism, nutrient absorption, and immune system development. Spinal cord injury (SCI) disrupts autonomic function below the level of injury and can alter the composition of the gut microbiome. Studies in rodent models have shown that SCI-induced bacterial imbalances in the gut can exacerbate the spinal cord damage and impair recovery. In this study we, for the first time, characterized the composition of the gut microbiome in a Yucatan minipig SCI model. We compared the relative abundance of the most dominant bacterial phyla in control samples to those collected from animals who underwent a contusion-compression SCI at the 2nd or 10th Thoracic level. RESULTS We identify specific bacterial fluctuations that are unique to SCI animals, which were not found in uninjured animals given the same dietary regimen or antibiotic administration. Further, we identified a specific time-frame, "SCI-acute stage", during which many of these bacterial fluctuations occur before returning to "baseline" levels. CONCLUSION This work presents a dynamic view of the microbiome changes that accompany SCI, establishes a resource for future studies and to understand the changes that occur to gut microbiota after spinal cord injury and may point to a potential therapeutic target for future treatment.
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Affiliation(s)
- Adam Doelman
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC Canada
| | - Seth Tigchelaar
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC Canada
| | - Brian McConeghy
- Sequencing and Bioinformatics Consortium, University of British Columbia, Vancouver, BC Canada
| | - Sunita Sinha
- Sequencing and Bioinformatics Consortium, University of British Columbia, Vancouver, BC Canada
| | - Martin S. Keung
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC Canada
| | - Neda Manouchehri
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC Canada
| | - Megan Webster
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC Canada
| | - Shera Fisk
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC Canada
| | - Charlotte Morrison
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC Canada
| | - Femke Streijger
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC Canada
| | - Corey Nislow
- Sequencing and Bioinformatics Consortium, University of British Columbia, Vancouver, BC Canada
| | - Brian K. Kwon
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC Canada
- Department of Orthopedics, Vancouver Spine Surgery Institute, University of British Columbia, Vancouver, BC Canada
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10
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Rycman A, McLachlin S, Cronin DS. A Hyper-Viscoelastic Continuum-Level Finite Element Model of the Spinal Cord Assessed for Transverse Indentation and Impact Loading. Front Bioeng Biotechnol 2021; 9:693120. [PMID: 34458242 PMCID: PMC8387872 DOI: 10.3389/fbioe.2021.693120] [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: 04/09/2021] [Accepted: 07/15/2021] [Indexed: 11/22/2022] Open
Abstract
Finite Element (FE) modelling of spinal cord response to impact can provide unique insights into the neural tissue response and injury risk potential. Yet, contemporary human body models (HBMs) used to examine injury risk and prevention across a wide range of impact scenarios often lack detailed integration of the spinal cord and surrounding tissues. The integration of a spinal cord in contemporary HBMs has been limited by the need for a continuum-level model owing to the relatively large element size required to be compatible with HBM, and the requirement for model development based on published material properties and validation using relevant non-linear material data. The goals of this study were to develop and assess non-linear material model parameters for the spinal cord parenchyma and pia mater, and incorporate these models into a continuum-level model of the spinal cord with a mesh size conducive to integration in HBM. First, hyper-viscoelastic material properties based on tissue-level mechanical test data for the spinal cord and hyperelastic material properties for the pia mater were determined. Secondly, the constitutive models were integrated in a spinal cord segment FE model validated against independent experimental data representing transverse compression of the spinal cord-pia mater complex (SCP) under quasi-static indentation and dynamic impact loading. The constitutive model parameters were fit to a quasi-linear viscoelastic model with an Ogden hyperelastic function, and then verified using single element test cases corresponding to the experimental strain rates for the spinal cord (0.32–77.22 s−1) and pia mater (0.05 s−1). Validation of the spinal cord model was then performed by re-creating, in an explicit FE code, two independent ex-vivo experimental setups: 1) transverse indentation of a porcine spinal cord-pia mater complex and 2) dynamic transverse impact of a bovine SCP. The indentation model accurately matched the experimental results up to 60% compression of the SCP, while the impact model predicted the loading phase and the maximum deformation (within 7%) of the SCP experimental data. This study quantified the important biomechanical contribution of the pia mater tissue during spinal cord deformation. The validated material models established in this study can be implemented in computational HBM.
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Affiliation(s)
- Aleksander Rycman
- Department of Mechanical and Mechatronics Engineering, University of Waterloo, Waterloo, ON, Canada
| | - Stewart McLachlin
- Department of Mechanical and Mechatronics Engineering, University of Waterloo, Waterloo, ON, Canada
| | - Duane S Cronin
- Department of Mechanical and Mechatronics Engineering, University of Waterloo, Waterloo, ON, Canada
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11
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Streijger F, Kim KT, So K, Manouchehri N, Shortt K, Okon EB, Morrison C, Fong A, Gupta R, Brown AA, Tigchelaar S, Sun J, Liu E, Keung M, Daly CD, Cripton PA, Sekhon MS, Griesdale DE, Kwon BK. Duraplasty in Traumatic Thoracic Spinal Cord Injury: Impact on Spinal Cord Hemodynamics, Tissue Metabolism, Histology, and Behavioral Recovery Using a Porcine Model. J Neurotrauma 2021; 38:2937-2955. [PMID: 34011164 DOI: 10.1089/neu.2021.0084] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
After acute traumatic spinal cord injury (SCI), the spinal cord can swell to fill the subarachnoid space and become compressed by the surrounding dura. In a porcine model of SCI, we performed a duraplasty to expand the subarachnoid space around the injured spinal cord and evaluated how this influenced acute intraparenchymal hemodynamic and metabolic responses, in addition to histological and behavioral recovery. Female Yucatan pigs underwent a T10 SCI, with or without duraplasty. Using microsensors implanted into the spinal cord parenchyma, changes in blood flow (ΔSCBF), oxygenation (ΔPO2), and spinal cord pressure (ΔSCP) during and after SCI were monitored, alongside metabolic responses. Behavioral recovery was tested weekly using the Porcine Injury Behavior Scale (PTIBS). Thereafter, spinal cords were harvested for tissue sparing analyses. In both duraplasty and non-animals, the ΔSCP increased ∼5 mm Hg in the first 6 h post-injury. After this, the SCP appeared to be slightly reduced in the duraplasty animals, although the group differences were not statistically significant after controlling for injury severity in terms of impact force. During the first seven days post-SCI, the ΔSCBF or ΔPO2 values were not different between the duraplasty and control animals. Over 12 weeks, there was no improvement in hindlimb locomotion as assessed by PTIBS scores and no reduction in tissue damage at the injury site in the duraplasty animals. In our porcine model of SCI, duraplasty did not provide any clear evidence of long-term behavioral or tissue sparing benefit after SCI.
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Affiliation(s)
- Femke Streijger
- International Collaboration on Repair Discoveries, University of British Columbia (UBC), Vancouver, British Columbia, Canada
| | - Kyoung-Tae Kim
- International Collaboration on Repair Discoveries, University of British Columbia (UBC), Vancouver, British Columbia, Canada.,Department of Neurosurgery, Kyungpook National University Hospital, Daegu, Korea.,Department of Neurosurgery, School of Medicine, Kyungpook National University, Daegu, Korea
| | - Kitty So
- International Collaboration on Repair Discoveries, University of British Columbia (UBC), Vancouver, British Columbia, Canada
| | - Neda Manouchehri
- International Collaboration on Repair Discoveries, University of British Columbia (UBC), Vancouver, British Columbia, Canada
| | - Katelyn Shortt
- International Collaboration on Repair Discoveries, University of British Columbia (UBC), Vancouver, British Columbia, Canada
| | - Elena B Okon
- International Collaboration on Repair Discoveries, University of British Columbia (UBC), Vancouver, British Columbia, Canada
| | - Charlotte Morrison
- International Collaboration on Repair Discoveries, University of British Columbia (UBC), Vancouver, British Columbia, Canada
| | - Allan Fong
- International Collaboration on Repair Discoveries, University of British Columbia (UBC), Vancouver, British Columbia, Canada
| | - Rishab Gupta
- International Collaboration on Repair Discoveries, University of British Columbia (UBC), Vancouver, British Columbia, Canada
| | - Aysha Allard Brown
- International Collaboration on Repair Discoveries, University of British Columbia (UBC), Vancouver, British Columbia, Canada
| | - Seth Tigchelaar
- International Collaboration on Repair Discoveries, University of British Columbia (UBC), Vancouver, British Columbia, Canada
| | - Jenny Sun
- International Collaboration on Repair Discoveries, University of British Columbia (UBC), Vancouver, British Columbia, Canada
| | - Ella Liu
- International Collaboration on Repair Discoveries, University of British Columbia (UBC), Vancouver, British Columbia, Canada
| | - Martin Keung
- International Collaboration on Repair Discoveries, University of British Columbia (UBC), Vancouver, British Columbia, Canada
| | - Chris D Daly
- Vancouver Spine Surgery Institute, Department of Orthopaedics, and University of British Columbia (UBC), Vancouver, British Columbia, Canada
| | - Peter A Cripton
- International Collaboration on Repair Discoveries, University of British Columbia (UBC), Vancouver, British Columbia, Canada.,School of Biomedical Engineering and Orthopedics, University of British Columbia (UBC), Vancouver, British Columbia, Canada
| | - Mypinder S Sekhon
- Division of Critical Care Medicine, Department of Medicine and Pharmacology and Therapeutics, Faculty of Medicine, Vancouver General Hospital, Vancouver, British Columbia, Canada
| | - Donald E Griesdale
- Division of Critical Care Medicine, Department of Anesthesiology, Pharmacology and Therapeutics, Faculty of Medicine, Vancouver General Hospital, Vancouver, British Columbia, Canada
| | - Brian K Kwon
- International Collaboration on Repair Discoveries, University of British Columbia (UBC), Vancouver, British Columbia, Canada.,Vancouver Spine Surgery Institute, Department of Orthopaedics, and University of British Columbia (UBC), Vancouver, British Columbia, Canada
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12
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Keung MS, Streijger F, Herrity A, Ethridge J, Dougherty SM, Aslan S, Webster M, Fisk S, Deegan EG, Tessier-Cloutier B, Chen KYN, Morrison C, Okon EB, Tigchelaar S, Manouchehri N, Kim KT, Shortt K, So K, Damaser MS, Sherwood LC, Howland DR, Boakye M, Hubscher C, Stothers L, Kavanagh A, Kwon BK. Characterization of Lower Urinary Tract Dysfunction after Thoracic Spinal Cord Injury in Yucatan Minipigs. J Neurotrauma 2021; 38:1306-1326. [PMID: 33499736 DOI: 10.1089/neu.2020.7404] [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] [Indexed: 01/23/2023] Open
Abstract
There is an increasing need to develop approaches that will not only improve the clinical management of neurogenic lower urinary tract dysfunction (NLUTD) after spinal cord injury (SCI), but also advance therapeutic interventions aimed at recovering bladder function. Although pre-clinical research frequently employs rodent SCI models, large animals such as the pig may play an important translational role in facilitating the development of devices or treatments. Therefore, the objective of this study was to develop a urodynamics protocol to characterize NLUTD in a porcine model of SCI. An iterative process to develop the protocol to perform urodynamics in female Yucatan minipigs began with a group of spinally intact, anesthetized pigs. Subsequently, urodynamic studies were performed in a group of awake, lightly restrained pigs, before and after a contusion-compression SCI at the T2 or T9-T11 spinal cord level. Bladder tissue was obtained for histological analysis at the end of the study. All anesthetized pigs had bladders that were acontractile, which resulted in overflow incontinence once capacity was reached. Uninjured, conscious pigs demonstrated appropriate relaxation and contraction of the external urethral sphincter during the voiding phase. SCI pigs demonstrated neurogenic detrusor overactivity and a significantly elevated post-void residual volume. Relative to the control, SCI bladders were heavier and thicker. The developed urodynamics protocol allows for repetitive evaluation of lower urinary tract function in pigs at different time points post-SCI. This technique manifests the potential for using the pig as an intermediary, large animal model for translational studies in NLUTD.
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Affiliation(s)
- Martin S Keung
- International Collaboration on Repair Discoveries (ICORD), Departments of Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,Neuroscience, Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Femke Streijger
- International Collaboration on Repair Discoveries (ICORD), Departments of Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - April Herrity
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, Kentucky, USA.,Department of Neurosurgery, University of Louisville, Louisville, Kentucky, USA
| | - Jay Ethridge
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, Kentucky, USA.,Department of Neurosurgery, University of Louisville, Louisville, Kentucky, USA
| | - Susan M Dougherty
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, Kentucky, USA.,Department of Neurosurgery, University of Louisville, Louisville, Kentucky, USA
| | - Sevda Aslan
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, Kentucky, USA.,Department of Neurosurgery, University of Louisville, Louisville, Kentucky, USA
| | - Megan Webster
- International Collaboration on Repair Discoveries (ICORD), Departments of Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Shera Fisk
- International Collaboration on Repair Discoveries (ICORD), Departments of Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Emily G Deegan
- International Collaboration on Repair Discoveries (ICORD), Departments of Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Basile Tessier-Cloutier
- Pathology and Laboratory Medicine, and Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kuan-Yin N Chen
- International Collaboration on Repair Discoveries (ICORD), Departments of Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Charlotte Morrison
- International Collaboration on Repair Discoveries (ICORD), Departments of Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Elena B Okon
- International Collaboration on Repair Discoveries (ICORD), Departments of Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Seth Tigchelaar
- International Collaboration on Repair Discoveries (ICORD), Departments of Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Neda Manouchehri
- International Collaboration on Repair Discoveries (ICORD), Departments of Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kyoung-Tae Kim
- International Collaboration on Repair Discoveries (ICORD), Departments of Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Neurosurgery, School of Medicine, Kyungpook National University, National University Hospital, Daegu, South Korea
| | - Katelyn Shortt
- International Collaboration on Repair Discoveries (ICORD), Departments of Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kitty So
- International Collaboration on Repair Discoveries (ICORD), Departments of Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Margot S Damaser
- Biomedical Engineering Department, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA.,Advanced Platform Technology Center, Louis Stokes Cleveland U.S. Department of Veterans Affairs Medical Center, Cleveland, Ohio, USA
| | - Leslie C Sherwood
- Comparative Medicine Research Unit, and University of Louisville, Louisville, Kentucky, USA
| | - Dena R Howland
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, Kentucky, USA.,Department of Neurosurgery, University of Louisville, Louisville, Kentucky, USA.,Research Service, Robley Rex U.S. Department of Veterans Affairs Medical Center, Louisville, Kentucky, USA
| | - Max Boakye
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, Kentucky, USA.,Department of Neurosurgery, University of Louisville, Louisville, Kentucky, USA
| | - Charles Hubscher
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, Kentucky, USA.,Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky, USA
| | - Lynn Stothers
- International Collaboration on Repair Discoveries (ICORD), Departments of Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,Urologic Sciences, and Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Alex Kavanagh
- Urologic Sciences, and Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Brian K Kwon
- International Collaboration on Repair Discoveries (ICORD), Departments of Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,Vancouver Spine Surgery Institute, Department of Orthopaedics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
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13
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Mukhamedshina Y, Zhuravleva M, Sergeev M, Zakirova E, Gracheva O, Mukhutdinova D, Rizvanov A. Improving Culture Conditions, Proliferation, and Migration of Porcine Mesenchymal Stem Cells on Spinal Cord Contusion Injury Model in vitro. Cells Tissues Organs 2021; 209:236-247. [PMID: 33508824 DOI: 10.1159/000511865] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 09/22/2020] [Indexed: 11/19/2022] Open
Abstract
Adipose tissue-derived mesenchymal stem cells (AD-MSCs) are promising for cell therapy in spinal cord injury (SCI). The pig is one of the most approximate models of many human diseases, including SCI. In our study, we selected the optimal conditions for the culture of porcine AD-MSCs and developed an in vitro SCI model based on the culture of cells in injured spinal cord extracts (SCE) 3 days and 6 weeks after SCI. We show that Dulbecco's Modified Eagle Medium (DMEM) with 20% serum content, supplemented with a combination of 5 mM L-ascorbate-2-phosphate and nonessential amino acids, stimulated a typical fibroblast-like morphology and high proliferation of porcine AD-MSCs. SCE caused a higher proliferation of porcine AD-MSCs compared with extracts from an intact spinal cord. The optimal proliferating effect was achieved using rostral 3 days SCE, and proliferation was lower in caudal and central SCE. Porcine AD-MSCs migration to the 3 days and 6 weeks SCE was higher than to an intact one and preferred the rostral SCE, avoiding central and caudal SCE. We also studied 13 cytokines contained in SCE but did not observe any definite relationship between some analyte concentrations and a change in the behavior of AD-MSCs.
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Affiliation(s)
- Yana Mukhamedshina
- Clinical Research Center for Precision and Regenerative Medicine, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russian Federation, .,Department of Histology, Cytology, and Embryology, Kazan State Medical University, Kazan, Russian Federation,
| | - Margarita Zhuravleva
- Clinical Research Center for Precision and Regenerative Medicine, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russian Federation
| | - Mikhail Sergeev
- Clinical Research Center for Precision and Regenerative Medicine, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russian Federation.,Department of Veterinary Surgery, Obstetrics and Small Animal Pathology, Kazan State Academy of Veterinary, Kazan, Russian Federation
| | - Elena Zakirova
- Clinical Research Center for Precision and Regenerative Medicine, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russian Federation
| | - Olga Gracheva
- Department of Therapy and Clinical Diagnostics with Radiology, Kazan State Academy of Veterinary, Kazan, Russian Federation
| | - Dina Mukhutdinova
- Department of Therapy and Clinical Diagnostics with Radiology, Kazan State Academy of Veterinary, Kazan, Russian Federation
| | - Albert Rizvanov
- Clinical Research Center for Precision and Regenerative Medicine, Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russian Federation
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14
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Huntemer-Silveira A, Patil N, Brickner MA, Parr AM. Strategies for Oligodendrocyte and Myelin Repair in Traumatic CNS Injury. Front Cell Neurosci 2021; 14:619707. [PMID: 33505250 PMCID: PMC7829188 DOI: 10.3389/fncel.2020.619707] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 12/07/2020] [Indexed: 12/18/2022] Open
Abstract
A major consequence of traumatic brain and spinal cord injury is the loss of the myelin sheath, a cholesterol-rich layer of insulation that wraps around axons of the nervous system. In the central nervous system (CNS), myelin is produced and maintained by oligodendrocytes. Damage to the CNS may result in oligodendrocyte cell death and subsequent loss of myelin, which can have serious consequences for functional recovery. Demyelination impairs neuronal function by decelerating signal transmission along the axon and has been implicated in many neurodegenerative diseases. After a traumatic injury, mechanisms of endogenous remyelination in the CNS are limited and often fail, for reasons that remain poorly understood. One area of research focuses on enhancing this endogenous response. Existing techniques include the use of small molecules, RNA interference (RNAi), and monoclonal antibodies that target specific signaling components of myelination for recovery. Cell-based replacement strategies geared towards replenishing oligodendrocytes and their progenitors have been utilized by several groups in the last decade as well. In this review article, we discuss the effects of traumatic injury on oligodendrocytes in the CNS, the lack of endogenous remyelination, translational studies in rodent models promoting remyelination, and finally human clinical studies on remyelination in the CNS after injury.
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Affiliation(s)
| | - Nandadevi Patil
- Department of Neurosurgery, Stem Cell Institute, University of Minnesota, Minneapolis, MN, United States
| | - Megan A. Brickner
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, United States
| | - Ann M. Parr
- Department of Neurosurgery, Stem Cell Institute, University of Minnesota, Minneapolis, MN, United States
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15
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Abstract
Spinal cord injury results in significant loss of motor, sensory, and autonomic functions. Although a wide range of therapeutic agents have been shown to attenuate secondary injury or promote regeneration/repair in animal models of spinal cord injury, clinical translation of these strategies has been limited, in part due to difficulty in safely and effectively achieving therapeutic concentrations in the injured spinal cord tissue. Hydrogel-based drug delivery systems offer unique opportunities to locally deliver drugs to the injured spinal cord with sufficient dose and duration, while avoiding deleterious side effects associated with systemic drug administration. Such local drug delivery systems can be readily fabricated from biocompatible and biodegradable materials. In this review, hydrogel-based strategies for local drug delivery to the injured spinal cord are extensively reviewed, and recommendations are made for implementation.
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Affiliation(s)
- Robert B Shultz
- School of Biomedical Engineering, Science and Health Systems, Drexel University; Department of Neurosurgery; Department of Bioengineering, University of Pennsylvania; New Jersey Center for Biomaterials, Rutgers - The State University of New Jersey, Piscataway, NJ; Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
| | - Yinghui Zhong
- School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA, USA
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16
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Epidural Stimulation Combined with Triple Gene Therapy for Spinal Cord Injury Treatment. Int J Mol Sci 2020; 21:ijms21238896. [PMID: 33255323 PMCID: PMC7734573 DOI: 10.3390/ijms21238896] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 11/06/2020] [Accepted: 11/17/2020] [Indexed: 12/18/2022] Open
Abstract
The translation of new therapies for spinal cord injury to clinical trials can be facilitated with large animal models close in morpho-physiological scale to humans. Here, we report functional restoration and morphological reorganization after spinal contusion in pigs, following a combined treatment of locomotor training facilitated with epidural electrical stimulation (EES) and cell-mediated triple gene therapy with umbilical cord blood mononuclear cells overexpressing recombinant vascular endothelial growth factor, glial-derived neurotrophic factor, and neural cell adhesion molecule. Preliminary results obtained on a small sample of pigs 2 months after spinal contusion revealed the difference in post-traumatic spinal cord outcomes in control and treated animals. In treated pigs, motor performance was enabled by EES and the corresponding morpho-functional changes in hind limb skeletal muscles were accompanied by the reorganization of the glial cell, the reaction of stress cell, and synaptic proteins. Our data demonstrate effects of combined EES-facilitated motor training and cell-mediated triple gene therapy after spinal contusion in large animals, informing a background for further animal studies and clinical translation.
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17
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Benasson I, Wagnac E, Diotalevi L, Moore D, Mac-Thiong JM, Petit Y. Gait analysis of a post induced traumatic spinal cord injury porcine model. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2020:3803-3806. [PMID: 33018829 DOI: 10.1109/embc44109.2020.9175280] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Porcine model constitutes a potential translational model to study traumatic spinal cord injuries (TSCI) considering its recent use in numerous studies. Recovery of the animal is currently monitored through a qualitative evaluation of the gait. Adding a quantitative evaluation might help to better assess the functional recovery of the animal. In this study, a new controlled method involving the use of an electro-magnetic actuator was used on a pig to induce a TSCI. Chronic monitoring was done using a quantitative analysis of the gait. Results show both, the injury of the pig and its functional recovery. This large animal model will help to provide a better understanding of injury and recovery mechanisms and thus could constitute a strong preclinical model for future therapeutic studies.Clinical Relevance- Methodology and results from this study would provide a better insight on the functional recovery after traumatic spinal cord injuries.
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18
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Galuta A, Sandarage R, Ghinda D, Auriat AM, Chen S, Kwan JCS, Tsai EC. A Guide to Extract Spinal Cord for Translational Stem Cell Biology Research: Comparative Analysis of Adult Human, Porcine, and Rodent Spinal Cord Stem Cells. Front Neurosci 2020; 14:607. [PMID: 32625055 PMCID: PMC7314920 DOI: 10.3389/fnins.2020.00607] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 05/18/2020] [Indexed: 11/25/2022] Open
Abstract
Improving the clinical translation of animal-based neural stem/progenitor cell (NSPC) therapies to humans requires an understanding of intrinsic human and animal cell characteristics. We report a novel in vitro method to assess spinal cord NSPCs from a small (rodent) and large (porcine) animal model in comparison to human NSPCs. To extract live adult human, porcine, and rodent spinal cord tissue, we illustrate a strategy using an anterior or posterior approach that was simulated in a porcine model. The initial expansion of primary NSPCs is carried out using the neurosphere assay followed by a pharmacological treatment phase during which NSPCs derived from humans, porcines, and rodents are assessed in parallel using the same defined parameters. Using this model, NSPCs from all species demonstrated multi-lineage differentiation and self-renewal. Importantly, these methods provide conditions to enable the direct comparison of species-dependent cell behavior in response to specific exogenous signals.
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Affiliation(s)
- Ahmad Galuta
- Department of Neurosciences, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada.,Neuroscience Program, Ottawa Hospital Research Institute, The Ottawa Hospital, Ottawa, ON, Canada
| | - Ryan Sandarage
- Department of Neurosciences, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada.,Faculty of Medicine, The University of British Columbia, Vancouver, BC, Canada
| | - Diana Ghinda
- Neuroscience Program, Ottawa Hospital Research Institute, The Ottawa Hospital, Ottawa, ON, Canada.,Division of Neurosurgery, Department of Surgery, The Ottawa Hospital, Ottawa, ON, Canada
| | - Angela M Auriat
- Neuroscience Program, Ottawa Hospital Research Institute, The Ottawa Hospital, Ottawa, ON, Canada
| | - Suzan Chen
- Neuroscience Program, Ottawa Hospital Research Institute, The Ottawa Hospital, Ottawa, ON, Canada
| | - Jason C S Kwan
- Department of Neurosciences, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada.,Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Eve C Tsai
- Department of Neurosciences, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada.,Neuroscience Program, Ottawa Hospital Research Institute, The Ottawa Hospital, Ottawa, ON, Canada.,Division of Neurosurgery, Department of Surgery, The Ottawa Hospital, Ottawa, ON, Canada
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19
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Holmes GM, Hubscher CH, Krassioukov A, Jakeman LB, Kleitman N. Recommendations for evaluation of bladder and bowel function in pre-clinical spinal cord injury research. J Spinal Cord Med 2019; 43:165-176. [PMID: 31556844 PMCID: PMC7054945 DOI: 10.1080/10790268.2019.1661697] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Objective: In order to encourage the inclusion of bladder and bowel outcome measures in preclinical spinal cord injury (SCI) research, this paper identifies and categorizes 1) fundamental, 2) recommended, 3) supplemental and 4) exploratory sets of outcome measures for pre-clinical assessment of bladder and bowel function with broad applicability to animal models of SCI.Methods: Drawing upon the collective research experience of autonomic physiologists and informed in consultation with clinical experts, a critical assessment of currently available bladder and bowel outcome measures (histological, biochemical, in vivo functional, ex vivo physiological and electrophysiological tests) was made to identify the strengths, deficiencies and ease of inclusion for future studies of experimental SCI.Results: Based upon pre-established criteria generated by the Neurogenic Bladder and Bowel Working Group that included history of use in experimental settings, citations in the literature by multiple independent groups, ease of general use, reproducibility and sensitivity to change, three fundamental measures each for bladder and bowel assessments were identified. Briefly defined, these assessments centered upon tissue morphology, voiding efficiency/volume and smooth muscle-mediated pressure studies. Additional assessment measures were categorized as recommended, supplemental or exploratory based upon the balance between technical requirements and potential mechanistic insights to be gained by the study.Conclusion: Several fundamental assessments share reasonable levels of technical and material investment, including some that could assess bladder and bowel function non-invasively and simultaneously. Such measures used more inclusively across SCI studies would advance progress in this high priority area. When complemented with a few additional investigator-selected study-relevant supplemental measures, they are highly recommended for research programs investigating the efficacy of therapeutic interventions in preclinical animal models of SCI that have a bladder and/or bowel focus.
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Affiliation(s)
- Gregory M. Holmes
- Neural and Behavioral Sciences, Pennsylvania State University College of Medicine, Hershey, Pennsylvania, USA,Correspondence to: Gregory M. Holmes, Neural and Behavioral Sciences, Pennsylvania State University College of Medicine, 500 University Dr., Hershey, PA 17036, USA. ;
| | - Charles H. Hubscher
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky, USA,Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, Kentucky, USA
| | - Andrei Krassioukov
- ICORD, University of British Columbia, GF Strong Rehabilitation Centre, Vancouver, Canada
| | - Lyn B. Jakeman
- National Institute of Neurological Disorders and Stroke, Bethesda, Maryland, USA
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20
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Tigchelaar S, Gupta R, Shannon CP, Streijger F, Sinha S, Flibotte S, Rizzuto MA, Street J, Paquette S, Ailon T, Charest-Morin R, Dea N, Fisher C, Dvorak MF, Dhall S, Mac-Thiong JM, Parent S, Bailey C, Christie S, Van Keuren-Jensen K, Nislow C, Kwon BK. MicroRNA Biomarkers in Cerebrospinal Fluid and Serum Reflect Injury Severity in Human Acute Traumatic Spinal Cord Injury. J Neurotrauma 2019; 36:2358-2371. [PMID: 30827169 DOI: 10.1089/neu.2018.6256] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Spinal cord injury (SCI) is a devastating condition with variability in injury mechanisms and neurologic recovery. Spinal cord impairment after SCI is measured and classified by a widely accepted standard neurological examination. In the very acute stages post-injury, however, this examination is extremely challenging (and often impossible) to conduct and has modest prognostic value in terms of neurological recovery. The lack of objective tools to classify injury severity and predict outcome is a barrier for clinical trials and thwarts development of therapies for those with SCI. Biological markers (biomarkers) represent a promising, complementary approach to these challenges because they represent an unbiased approach to classify injury severity and predict neurological outcome. Identification of a suitable panel of molecular biomarkers would comprise a fundamental shift in how patients with acute SCI are evaluated, stratified, and treated in clinical trials. MicroRNA are attractive biomarker candidates in neurological disorders for several reasons, including their stability in biological fluids, their conservation between humans and model mammals, and their tissue specificity. In this study, we used next-generation sequencing to identify microRNA associated with injury severity within the cerebrospinal fluid (CSF) and serum of human patients with acute SCI. The CSF and serum samples were obtained 1-5 days post-injury from 39 patients with acute SCI (24 American Spinal Injury Association Impairment Scale [AIS] A, 8 AIS B, 7 AIS C) and from five non-SCI controls. We identified a severity-dependent pattern of change in microRNA expression in CSF and identified a set of microRNA that are diagnostic of baseline AIS classification and prognostic of neurological outcome six months post-injury. The data presented here provide a comprehensive description of the CSF and serum microRNA expression changes that occur after acute human SCI. This data set reveals microRNA candidates that warrant further evaluation as biomarkers of injury severity after SCI and as key regulators in other neurological disorders.
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Affiliation(s)
- Seth Tigchelaar
- 1International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
| | - Rishab Gupta
- 1International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
| | - Casey P Shannon
- 2Prevention of Organ Failure (PROOF) Centre of Excellence, Vancouver, British Columbia, Canada
| | - Femke Streijger
- 1International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
| | - Sunita Sinha
- 3Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Stephane Flibotte
- 3Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Michael A Rizzuto
- 1International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada
| | - John Street
- 4Department of Orthopedics, Division of Spine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Scott Paquette
- 5Division of Neurosurgery, University of British Columbia, Vancouver, British Columbia, Canada
| | - Tamir Ailon
- 5Division of Neurosurgery, University of British Columbia, Vancouver, British Columbia, Canada
| | - Raphaele Charest-Morin
- 4Department of Orthopedics, Division of Spine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Nicolas Dea
- 5Division of Neurosurgery, University of British Columbia, Vancouver, British Columbia, Canada
| | - Charles Fisher
- 4Department of Orthopedics, Division of Spine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Marcel F Dvorak
- 1International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada.,4Department of Orthopedics, Division of Spine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Sanjay Dhall
- 6Department of Neurosurgery, University of California San Francisco, San Francisco, California
| | | | - Stefan Parent
- 8Department of Surgery, Chu Sainte-Justine, University of Montreal, Montreal, Quebec, Canada
| | - Christopher Bailey
- 9Division of Orthopaedic Surgery, Schulich Medicine & Dentistry, Victoria Hospital, London, Ontario, Canada
| | - Sean Christie
- 10Division of Neurosurgery, Halifax Infirmary, Dalhousie University, Halifax, Nova Scotia, Canada
| | | | - Corey Nislow
- 3Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Brian K Kwon
- 1International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada.,4Department of Orthopedics, Division of Spine, University of British Columbia, Vancouver, British Columbia, Canada
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