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Tang Q, Ma Y, Cheng Q, Wu Y, Chen J, Du J, Lu P, Chang EY. Longitudinal Imaging of Injured Spinal Cord Myelin and White Matter with 3D Ultrashort Echo Time Magnetization Transfer (UTE-MT) and Diffusion MRI. J Imaging 2024; 10:213. [PMID: 39330433 PMCID: PMC11433189 DOI: 10.3390/jimaging10090213] [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: 07/12/2024] [Revised: 08/06/2024] [Accepted: 08/27/2024] [Indexed: 09/28/2024] Open
Abstract
Quantitative MRI techniques could be helpful to noninvasively and longitudinally monitor dynamic changes in spinal cord white matter following injury, but imaging and postprocessing techniques in small animals remain lacking. Unilateral C5 hemisection lesions were created in a rat model, and ultrashort echo time magnetization transfer (UTE-MT) and diffusion-weighted sequences were used for imaging following injury. Magnetization transfer ratio (MTR) measurements and preferential diffusion along the longitudinal axis of the spinal cord were calculated as fractional anisotropy or an apparent diffusion coefficient ratio over transverse directions. The area of myelinated white matter was obtained by thresholding the spinal cord using mean MTR or diffusion ratio values from the contralesional side of the spinal cord. A decrease in white matter areas was observed on the ipsilesional side caudal to the lesions, which is consistent with known myelin and axonal changes following spinal cord injury. The myelinated white matter area obtained through the UTE-MT technique and the white matter area obtained through diffusion imaging techniques showed better performance to distinguish evolution after injury (AUCs > 0.94, p < 0.001) than the mean MTR (AUC = 0.74, p = 0.01) or ADC ratio (AUC = 0.68, p = 0.05) values themselves. Immunostaining for myelin basic protein (MBP) and neurofilament protein NF200 (NF200) showed atrophy and axonal degeneration, confirming the MRI results. These compositional and microstructural MRI techniques may be used to detect demyelination or remyelination in the spinal cord after spinal cord injury.
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Affiliation(s)
- Qingbo Tang
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA; (Q.T.); (Q.C.); (Y.W.); (J.C.); (J.D.); (P.L.)
- Department of Radiology, University of California, San Diego, CA 92093, USA;
| | - Yajun Ma
- Department of Radiology, University of California, San Diego, CA 92093, USA;
| | - Qun Cheng
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA; (Q.T.); (Q.C.); (Y.W.); (J.C.); (J.D.); (P.L.)
- Department of Neuroscience, University of California, San Diego, CA 92093, USA
| | - Yuanshan Wu
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA; (Q.T.); (Q.C.); (Y.W.); (J.C.); (J.D.); (P.L.)
- Department of Bioengineering, University of California, San Diego, CA 92093, USA
| | - Junyuan Chen
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA; (Q.T.); (Q.C.); (Y.W.); (J.C.); (J.D.); (P.L.)
- Department of Radiology, University of California, San Diego, CA 92093, USA;
- Department of Bone and Joint Surgery, The First Affiliated Hospital, Jinan University, Guangzhou 510632, China
| | - Jiang Du
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA; (Q.T.); (Q.C.); (Y.W.); (J.C.); (J.D.); (P.L.)
- Department of Radiology, University of California, San Diego, CA 92093, USA;
| | - Pengzhe Lu
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA; (Q.T.); (Q.C.); (Y.W.); (J.C.); (J.D.); (P.L.)
- Department of Neuroscience, University of California, San Diego, CA 92093, USA
| | - Eric Y. Chang
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA; (Q.T.); (Q.C.); (Y.W.); (J.C.); (J.D.); (P.L.)
- Radiology Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA
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Mitsuhashi M, Yamaguchi R, Kawasaki T, Ueno S, Sun Y, Isa K, Takahashi J, Kobayashi K, Onoe H, Takahashi R, Isa T. Stage-dependent role of interhemispheric pathway for motor recovery in primates. Nat Commun 2024; 15:6762. [PMID: 39174504 PMCID: PMC11341697 DOI: 10.1038/s41467-024-51070-w] [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: 12/19/2023] [Accepted: 07/26/2024] [Indexed: 08/24/2024] Open
Abstract
Whether and how the non-lesional sensorimotor cortex is activated and contributes to post-injury motor recovery is controversial. Here, we investigated the role of interhemispheric pathway from the contralesional to ipsilesional premotor cortex in activating the ipsilesional sensorimotor cortex and promoting recovery after lesioning the lateral corticospinal tract at the cervical cord, by unidirectional chemogenetic blockade in macaques. The blockade impaired dexterous hand movements during the early recovery stage. Electrocorticographical recording showed that the low frequency band activity of the ipsilesional premotor cortex around movement onset was decreased by the blockade during the early recovery stage, while it was increased by blockade during the intact state and late recovery stage. These results demonstrate that action of the interhemispheric pathway changed from inhibition to facilitation, to involve the ipsilesional sensorimotor cortex in hand movements during the early recovery stage. The present study offers insights into the stage-dependent role of the interhemispheric pathway and a therapeutic target in the early recovery stage after lesioning of the corticospinal tract.
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Affiliation(s)
- Masahiro Mitsuhashi
- Department of Neuroscience, Graduate School of Medicine, Kyoto University, Kyoto, 606-8501, Japan
- Department of Neurology, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan
| | - Reona Yamaguchi
- Institute for the Advanced Study of Human Biology (WPI-ASHBi), Kyoto University, Kyoto, 606-8501, Japan
| | - Toshinari Kawasaki
- Department of Neuroscience, Graduate School of Medicine, Kyoto University, Kyoto, 606-8501, Japan
- Department of Neurosurgery, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan
| | - Satoko Ueno
- Department of Neuroscience, Graduate School of Medicine, Kyoto University, Kyoto, 606-8501, Japan
- Institute for the Advanced Study of Human Biology (WPI-ASHBi), Kyoto University, Kyoto, 606-8501, Japan
| | - Yiping Sun
- Department of Neuroscience, Graduate School of Medicine, Kyoto University, Kyoto, 606-8501, Japan
| | - Kaoru Isa
- Department of Neuroscience, Graduate School of Medicine, Kyoto University, Kyoto, 606-8501, Japan
| | - Jun Takahashi
- Department of Clinical Application, Center for iPS Cell Research and Application, Kyoto University, Kyoto, 606-8507, Japan
| | - Kenta Kobayashi
- Section of Viral Vector Development, National Institute for Physiological Sciences, Okazaki, 444-8585, Japan
- Graduate University of Advanced Studies (SOKENDAI), Hayama, 240-0193, Japan
| | - Hirotaka Onoe
- Human Brain Research Center, Graduate School of Medicine, Kyoto University, Kyoto, 606-8397, Japan
| | - Ryosuke Takahashi
- Department of Neurology, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan
| | - Tadashi Isa
- Department of Neuroscience, Graduate School of Medicine, Kyoto University, Kyoto, 606-8501, Japan.
- Institute for the Advanced Study of Human Biology (WPI-ASHBi), Kyoto University, Kyoto, 606-8501, Japan.
- Human Brain Research Center, Graduate School of Medicine, Kyoto University, Kyoto, 606-8397, Japan.
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Woodington BJ, Lei J, Carnicer-Lombarte A, Güemes-González A, Naegele TE, Hilton S, El-Hadwe S, Trivedi RA, Malliaras GG, Barone DG. Flexible circumferential bioelectronics to enable 360-degree recording and stimulation of the spinal cord. SCIENCE ADVANCES 2024; 10:eadl1230. [PMID: 38718109 PMCID: PMC11078185 DOI: 10.1126/sciadv.adl1230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 04/04/2024] [Indexed: 05/12/2024]
Abstract
The spinal cord is crucial for transmitting motor and sensory information between the brain and peripheral systems. Spinal cord injuries can lead to severe consequences, including paralysis and autonomic dysfunction. We introduce thin-film, flexible electronics for circumferential interfacing with the spinal cord. This method enables simultaneous recording and stimulation of dorsal, lateral, and ventral tracts with a single device. Our findings include successful motor and sensory signal capture and elicitation in anesthetized rats, a proof-of-concept closed-loop system for bridging complete spinal cord injuries, and device safety verification in freely moving rodents. Moreover, we demonstrate potential for human application through a cadaver model. This method sees a clear route to the clinic by using materials and surgical practices that mitigate risk during implantation and preserve cord integrity.
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Affiliation(s)
- Ben J. Woodington
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
| | - Jiang Lei
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | | | - Amparo Güemes-González
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
| | - Tobias E. Naegele
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
| | - Sam Hilton
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
| | - Salim El-Hadwe
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Rikin A. Trivedi
- Division of Neurosurgery, Addenbrookes Hospital, Hills Road, Cambridge, UK
| | - George G. Malliaras
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
| | - Damiano G. Barone
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
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Regniez M, Dufort-Gervais J, Provost C, Mongrain V, Martinez M. Characterization of Sleep, Emotional, and Cognitive Functions in a New Rat Model of Concomitant Spinal Cord and Traumatic Brain Injuries. J Neurotrauma 2024; 41:1044-1059. [PMID: 37885242 DOI: 10.1089/neu.2023.0387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2023] Open
Abstract
Traumatic injuries to the spinal cord or the brain have serious medical consequences and lead to long-term disability. The epidemiology, medical complications, and prognosis of isolated spinal cord injury (SCI) and traumatic brain injury (TBI) have been well described. However, there are limited data on patients suffering from concurrent SCI and TBI, even if a large proportion of SCI patients have concomitant TBI. The complications associated with this "dual-diagnosis" such as cognitive or behavioral dysfunction are well known in the rehabilitation setting, but evidence-based and standardized approaches for diagnosis and treatment are lacking. Our goal was to develop and characterize a pre-clinical animal model of concurrent SCI and TBI to help identifying "dual-diagnosis" tools. Female rats received a unilateral contusive SCI at the thoracic level alone (SCI group) or combined with a TBI centered on the contralateral sensorimotor cortex (SCI-TBI group). We first validated that the SCI extent was comparable between SCI-TBI and SCI groups, and that hindlimb function was impaired. We characterized various neurological outcomes, including locomotion, sleep architecture, brain activity during sleep, depressive- and anxiety-like behaviors, and working memory. We report that SCI-TBI and SCI groups show similar impairments in global locomotor function. While wake/sleep amount and distribution and anxiety- and depression-like symptoms were not affected in SCI-TBI and SCI groups in comparison to the control group (laminectomy and craniotomy only), working memory was impaired only in SCI-TBI rats. This pre-clinical model of concomitant SCI and TBI, including more severe variations of it, shows a translational value for the identification of biomarkers to refine the "dual-diagnosis" of neurotrauma in humans.
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Affiliation(s)
- Morgane Regniez
- Department of Neuroscience, Université de Montreal, Montréal, Québec, Canada
- Recherche CIUSSS-NIM, Montréal, Québec, Canada
| | | | | | - Valérie Mongrain
- Department of Neuroscience, Université de Montreal, Montréal, Québec, Canada
- Recherche CIUSSS-NIM, Montréal, Québec, Canada
- Research Center of the CHUM, Montréal, Québec, Canada
| | - Marina Martinez
- Department of Neuroscience, Université de Montreal, Montréal, Québec, Canada
- Recherche CIUSSS-NIM, Montréal, Québec, Canada
- Groupe de recherche sur la Signalisation Neurale et la Circuiterie, Université de Montreal, Montréal, Québec, Canada
- Centre interdisciplinaire de recherche sur le cerveau et l'apprentissage, Université de Montreal, Montréal, Québec, Canada
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Lemieux M, Karimi N, Bretzner F. Functional plasticity of glutamatergic neurons of medullary reticular nuclei after spinal cord injury in mice. Nat Commun 2024; 15:1542. [PMID: 38378819 PMCID: PMC10879492 DOI: 10.1038/s41467-024-45300-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 01/17/2024] [Indexed: 02/22/2024] Open
Abstract
Spinal cord injury disrupts the descending command from the brain and causes a range of motor deficits. Here, we use optogenetic tools to investigate the functional plasticity of the glutamatergic reticulospinal drive of the medullary reticular formation after a lateral thoracic hemisection in female mice. Sites evoking stronger excitatory descending drive in intact conditions are the most impaired after injury, whereas those associated with a weaker drive are potentiated. After lesion, pro- and anti-locomotor activities (that is, initiation/acceleration versus stop/deceleration) are overall preserved. Activating the descending reticulospinal drive improves stepping ability on a flat surface of chronically impaired injured mice, and its priming enhances recovery of skilled locomotion on a horizontal ladder. This study highlights the resilience and capacity for reorganization of the glutamatergic reticulospinal command after injury, along with its suitability as a therapeutical target to promote functional recovery.
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Affiliation(s)
- Maxime Lemieux
- Centre de Recherche du CHU de Québec, CHUL-Neurosciences, 2705 Boul. Laurier, Québec, QC, G1V 4G2, Canada
| | - Narges Karimi
- Centre de Recherche du CHU de Québec, CHUL-Neurosciences, 2705 Boul. Laurier, Québec, QC, G1V 4G2, Canada
- Faculty of Medicine, Department of Psychiatry and Neurosciences, Université Laval, Québec, QC, G1V 4G2, Canada
| | - Frederic Bretzner
- Centre de Recherche du CHU de Québec, CHUL-Neurosciences, 2705 Boul. Laurier, Québec, QC, G1V 4G2, Canada.
- Faculty of Medicine, Department of Psychiatry and Neurosciences, Université Laval, Québec, QC, G1V 4G2, Canada.
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Behroozi Z, Rahimi B, Motamednezhad A, Ghadaksaz A, Hormozi-Moghaddam Z, Moshiri A, Jafarpour M, Hajimirzaei P, Ataie A, Janzadeh A. Combined effect of Cerium oxide nanoparticles loaded scaffold and photobiomodulation therapy on pain and neuronal regeneration following spinal cord injury: an experimental study. Photochem Photobiol Sci 2024; 23:225-243. [PMID: 38300466 DOI: 10.1007/s43630-023-00501-6] [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: 08/31/2023] [Accepted: 10/25/2023] [Indexed: 02/02/2024]
Abstract
BACKGROUND Spinal cord injury (SCI) remained one of the challenges to treat due to its complicated mechanisms. Photobiomodulation therapy (PBMT) accelerates neuronal regeneration. Cerium oxide nanoparticles (CeONPs) also eliminate free radicals in the environment. The present study aims to introduce a combined treatment method of making PCL scaffolds as microenvironments, seeded with CeONPs and the PBMT technique for SCI treatment. METHODS The surgical hemi-section was used to induce SCI. Immediately after the SCI induction, the scaffold (Sc) was loaded with CeONPs implanted. PBMT began 30 min after SCI induction and lasted for up to 4 weeks. Fifty-six male rats were randomly divided into seven groups. Glial fibrillary acidic protein (GFAP) (an astrocyte marker), Connexin 43 (Con43) (a member of the gap junction), and gap junctions (GJ) (a marker for the transfer of ions and small molecules) expressions were evaluated. The behavioral evaluation was performed by BBB, Acetone, Von Frey, and radiant heat tests. RESULT The SC + Nano + PBMT group exhibited the most remarkable recovery outcomes. Thermal hyperalgesia responses were mitigated, with the combined approach displaying the most effective relief. Mechanical allodynia and cold allodynia responses were also attenuated by treatments, demonstrating potential pain management benefits. CONCLUSION These findings highlight the potential of PBMT, combined with CeONPs-loaded scaffolds, in promoting functional motor recovery and alleviating pain-related responses following SCI. The study underscores the intricate interplay between various interventions and their cumulative effects, informing future research directions for enhancing neural repair and pain management strategies in SCI contexts.
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Affiliation(s)
- Zahra Behroozi
- Physiology Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, 7616913555, Iran
| | - Behnaz Rahimi
- Physiology Research Center, Iran University of Medical Sciences, Tehran, 1449614535, Iran
| | - Ali Motamednezhad
- College of Veterinary Medicine, Islamic Azad University, Karaj, 3149968111, Alborz, Iran
| | - Alireza Ghadaksaz
- Department of Biophysics, Medical School, University of Pécs, Pécs, 7622, Hungary
| | - Zeinab Hormozi-Moghaddam
- Radiation Biology Research Center, Iran University of Medical Sciences, Tehran, 1449614535, Iran
- Department of Radiation Sciences, Allied Medicine Faculty, Iran University of Medical Sciences, Tehran, 1449614535, Iran
| | | | - Maral Jafarpour
- International Campus, Iran University of Medical Sciences, Tehran, 1449614535, Iran
| | - Pooya Hajimirzaei
- Radiation Biology Research Center, Iran University of Medical Sciences, Tehran, 1449614535, Iran
- Department of Radiation Sciences, Allied Medicine Faculty, Iran University of Medical Sciences, Tehran, 1449614535, Iran
| | - Ali Ataie
- Zanjan University of Medical Sciences, Zanjan, Iran
| | - Atousa Janzadeh
- Radiation Biology Research Center, Iran University of Medical Sciences, Tehran, 1449614535, Iran.
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Liu Q, Yang H, Luo J, Peng C, Wang K, Zhang G, Lin H, Ji Z. 14-3-3 protein augments the protein stability of phosphorylated spastin and promotes the recovery of spinal cord injury through its agonist intervention. eLife 2024; 12:RP90184. [PMID: 38231910 PMCID: PMC10945579 DOI: 10.7554/elife.90184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2024] Open
Abstract
Axon regeneration is abortive in the central nervous system following injury. Orchestrating microtubule dynamics has emerged as a promising approach to improve axonal regeneration. The microtubule severing enzyme spastin is essential for axonal development and regeneration through remodeling of microtubule arrangement. To date, however, little is known regarding the mechanisms underlying spastin action in neural regeneration after spinal cord injury. Here, we use glutathione transferase pulldown and immunoprecipitation assays to demonstrate that 14-3-3 interacts with spastin, both in vivo and in vitro, via spastin Ser233 phosphorylation. Moreover, we show that 14-3-3 protects spastin from degradation by inhibiting the ubiquitination pathway and upregulates the spastin-dependent severing ability. Furthermore, the 14-3-3 agonist Fusicoccin (FC-A) promotes neurite outgrowth and regeneration in vitro which needs spastin activation. Western blot and immunofluorescence results revealed that 14-3-3 protein is upregulated in the neuronal compartment after spinal cord injury in vivo. In addition, administration of FC-A not only promotes locomotor recovery, but also nerve regeneration following spinal cord injury in both contusion and lateral hemisection models; however, the application of spastin inhibitor spastazoline successfully reverses these phenomena. Taken together, these results indicate that 14-3-3 is a molecular switch that regulates spastin protein levels, and the small molecule 14-3-3 agonist FC-A effectively mediates the recovery of spinal cord injury in mice which requires spastin participation.
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Affiliation(s)
- Qiuling Liu
- Department of Orthopedics, The First Affiliated Hospital of Jinan UniversityGuangzhouChina
| | - Hua Yang
- Department of Orthopedics, The First Affiliated Hospital of Jinan UniversityGuangzhouChina
| | - Jianxian Luo
- Department of Orthopedics, The First Affiliated Hospital of Jinan UniversityGuangzhouChina
| | - Cheng Peng
- Department of Orthopedics, The First Affiliated Hospital of Jinan UniversityGuangzhouChina
| | - Ke Wang
- Department of Orthopedics, The First Affiliated Hospital of Jinan UniversityGuangzhouChina
| | - Guowei Zhang
- Department of Orthopedics, The First Affiliated Hospital of Jinan UniversityGuangzhouChina
| | - Hongsheng Lin
- Department of Orthopedics, The First Affiliated Hospital of Jinan UniversityGuangzhouChina
| | - Zhisheng Ji
- Department of Orthopedics, The First Affiliated Hospital of Jinan UniversityGuangzhouChina
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Martinez M. A bi-cortical neuroprosthesis to modulate locomotion after incomplete spinal cord injury. Sci Prog 2023; 106:368504231212788. [PMID: 38189274 PMCID: PMC10775731 DOI: 10.1177/00368504231212788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Neuroprosthetic strategies seek to immediately alleviate deficits and reinstate voluntary control of movement. To facilitate recovery, it is crucial to gain a comprehensive understanding of the mechanisms involved in the return of intentional movement. Nevertheless, the precise relationship between the resurgence of cortical commands and the recovery of locomotion remains somewhat elusive. In the study conducted by Duguay, Bonizzato, Delivet-Mongrain, Fortier-Lebel and Martinez, we introduced a neuroprosthesis designed to deliver precise bi-cortical stimulation in a clinically relevant contusive spinal cord injury model. We conducted experiments in both healthy and spinal cord injured cats, where we fine-tuned the timing, duration, amplitude, and site of stimulation to modulate hindlimb locomotor output. In healthy cats, we observed a wide range of motor programs. However, after spinal cord injury, the induced hindlimb movements became highly stereotyped but were effective in modulating gait and reducing bilateral foot dragging. These results suggest that the neural basis for motor recovery traded off selectivity for effectiveness. Through a series of longitudinal assessments, we found that the restoration of locomotion following spinal cord injury was closely linked to the recovery of the descending neural drive. This underscores the importance of directing rehabilitation interventions toward the cortical target. The study results are discussed in terms of their impact and limitations.
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Affiliation(s)
- Marina Martinez
- Marina Martinez, Département de neurosciences, Faculté de médecine, Université de Montréal, C.P. 6128, Succ. Centre-ville, Montréal, Québec, H3C 3J7, Canada.
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9
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Duguay M, Bonizzato M, Delivet-Mongrain H, Fortier-Lebel N, Martinez M. Uncovering and leveraging the return of voluntary motor programs after paralysis using a bi-cortical neuroprosthesis. Prog Neurobiol 2023; 228:102492. [PMID: 37414352 DOI: 10.1016/j.pneurobio.2023.102492] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 06/26/2023] [Accepted: 06/26/2023] [Indexed: 07/08/2023]
Abstract
Rehabilitative and neuroprosthetic approaches after spinal cord injury (SCI) aim to reestablish voluntary control of movement. Promoting recovery requires a mechanistic understanding of the return of volition over action, but the relationship between re-emerging cortical commands and the return of locomotion is not well established. We introduced a neuroprosthesis delivering targeted bi-cortical stimulation in a clinically relevant contusive SCI model. In healthy and SCI cats, we controlled hindlimb locomotor output by tuning stimulation timing, duration, amplitude, and site. In intact cats, we unveiled a large repertoire of motor programs. After SCI, the evoked hindlimb lifts were highly stereotyped, yet effective in modulating gait and alleviating bilateral foot drag. Results suggest that the neural substrate underpinning motor recovery had traded-off selectivity for efficacy. Longitudinal tests revealed that the return of locomotion after SCI was correlated with recovery of the descending drive, which advocates for rehabilitation interventions directed at the cortical target.
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Affiliation(s)
- Maude Duguay
- Département de Neurosciences and Centre interdisciplinaire de recherche sur le cerveau et l'apprentissage (CIRCA), Université de Montréal, Québec, Canada; CIUSSS du Nord-de-l'Île-de-Montréal, Québec, Canada
| | - Marco Bonizzato
- Département de Neurosciences and Centre interdisciplinaire de recherche sur le cerveau et l'apprentissage (CIRCA), Université de Montréal, Québec, Canada; CIUSSS du Nord-de-l'Île-de-Montréal, Québec, Canada; Department of Electrical Engineering, Polytechnique Montréal, Québec, Canada
| | - Hugo Delivet-Mongrain
- Département de Neurosciences and Centre interdisciplinaire de recherche sur le cerveau et l'apprentissage (CIRCA), Université de Montréal, Québec, Canada
| | - Nicolas Fortier-Lebel
- Département de Neurosciences and Centre interdisciplinaire de recherche sur le cerveau et l'apprentissage (CIRCA), Université de Montréal, Québec, Canada
| | - Marina Martinez
- Département de Neurosciences and Centre interdisciplinaire de recherche sur le cerveau et l'apprentissage (CIRCA), Université de Montréal, Québec, Canada; CIUSSS du Nord-de-l'Île-de-Montréal, Québec, Canada.
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10
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Bonizzato M, Guay Hottin R, Côté SL, Massai E, Choinière L, Macar U, Laferrière S, Sirpal P, Quessy S, Lajoie G, Martinez M, Dancause N. Autonomous optimization of neuroprosthetic stimulation parameters that drive the motor cortex and spinal cord outputs in rats and monkeys. Cell Rep Med 2023; 4:101008. [PMID: 37044093 PMCID: PMC10140617 DOI: 10.1016/j.xcrm.2023.101008] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 02/16/2023] [Accepted: 03/20/2023] [Indexed: 04/14/2023]
Abstract
Neural stimulation can alleviate paralysis and sensory deficits. Novel high-density neural interfaces can enable refined and multipronged neurostimulation interventions. To achieve this, it is essential to develop algorithmic frameworks capable of handling optimization in large parameter spaces. Here, we leveraged an algorithmic class, Gaussian-process (GP)-based Bayesian optimization (BO), to solve this problem. We show that GP-BO efficiently explores the neurostimulation space, outperforming other search strategies after testing only a fraction of the possible combinations. Through a series of real-time multi-dimensional neurostimulation experiments, we demonstrate optimization across diverse biological targets (brain, spinal cord), animal models (rats, non-human primates), in healthy subjects, and in neuroprosthetic intervention after injury, for both immediate and continual learning over multiple sessions. GP-BO can embed and improve "prior" expert/clinical knowledge to dramatically enhance its performance. These results advocate for broader establishment of learning agents as structural elements of neuroprosthetic design, enabling personalization and maximization of therapeutic effectiveness.
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Affiliation(s)
- Marco Bonizzato
- Department of Neurosciences and Centre interdisciplinaire de recherche sur le cerveau et l'apprentissage (CIRCA), Université de Montréal, Montreal, QC H3T 1J4, Canada; Department of Electrical Engineering and Institute of Biomedical Engineering, Polytechnique Montréal, Montreal, QC H3T 1J4, Canada; CIUSSS du Nord-de-l'Île-de-Montréal, Montreal, QC H4J 1C5, Canada; Mila - Québec AI Institute, Montreal, QC H2S 3H1, Canada.
| | - Rose Guay Hottin
- Department of Neurosciences and Centre interdisciplinaire de recherche sur le cerveau et l'apprentissage (CIRCA), Université de Montréal, Montreal, QC H3T 1J4, Canada; Department of Electrical Engineering and Institute of Biomedical Engineering, Polytechnique Montréal, Montreal, QC H3T 1J4, Canada; Mila - Québec AI Institute, Montreal, QC H2S 3H1, Canada
| | - Sandrine L Côté
- Department of Neurosciences and Centre interdisciplinaire de recherche sur le cerveau et l'apprentissage (CIRCA), Université de Montréal, Montreal, QC H3T 1J4, Canada
| | - Elena Massai
- Department of Neurosciences and Centre interdisciplinaire de recherche sur le cerveau et l'apprentissage (CIRCA), Université de Montréal, Montreal, QC H3T 1J4, Canada
| | - Léo Choinière
- Department of Neurosciences and Centre interdisciplinaire de recherche sur le cerveau et l'apprentissage (CIRCA), Université de Montréal, Montreal, QC H3T 1J4, Canada; Mila - Québec AI Institute, Montreal, QC H2S 3H1, Canada
| | - Uzay Macar
- Department of Neurosciences and Centre interdisciplinaire de recherche sur le cerveau et l'apprentissage (CIRCA), Université de Montréal, Montreal, QC H3T 1J4, Canada; Mila - Québec AI Institute, Montreal, QC H2S 3H1, Canada
| | - Samuel Laferrière
- Mila - Québec AI Institute, Montreal, QC H2S 3H1, Canada; Computer Science Department, Université de Montréal, Montreal, QC H3T 1J4, Canada
| | - Parikshat Sirpal
- Department of Neurosciences and Centre interdisciplinaire de recherche sur le cerveau et l'apprentissage (CIRCA), Université de Montréal, Montreal, QC H3T 1J4, Canada; Mila - Québec AI Institute, Montreal, QC H2S 3H1, Canada
| | - Stephan Quessy
- Department of Neurosciences and Centre interdisciplinaire de recherche sur le cerveau et l'apprentissage (CIRCA), Université de Montréal, Montreal, QC H3T 1J4, Canada
| | - Guillaume Lajoie
- Mila - Québec AI Institute, Montreal, QC H2S 3H1, Canada; Mathematics and Statistics Department, Université de Montréal, Montreal, QC H3T 1J4, Canada
| | - Marina Martinez
- Department of Neurosciences and Centre interdisciplinaire de recherche sur le cerveau et l'apprentissage (CIRCA), Université de Montréal, Montreal, QC H3T 1J4, Canada; CIUSSS du Nord-de-l'Île-de-Montréal, Montreal, QC H4J 1C5, Canada
| | - Numa Dancause
- Department of Neurosciences and Centre interdisciplinaire de recherche sur le cerveau et l'apprentissage (CIRCA), Université de Montréal, Montreal, QC H3T 1J4, Canada.
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11
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Roussel M, Lafrance-Zoubga D, Josset N, Lemieux M, Bretzner F. Functional contribution of mesencephalic locomotor region nuclei to locomotor recovery after spinal cord injury. Cell Rep Med 2023; 4:100946. [PMID: 36812893 PMCID: PMC9975330 DOI: 10.1016/j.xcrm.2023.100946] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 12/09/2022] [Accepted: 01/23/2023] [Indexed: 02/23/2023]
Abstract
Spinal cord injury (SCI) results in a disruption of information between the brain and the spinal circuit. Electrical stimulation of the mesencephalic locomotor region (MLR) can promote locomotor recovery in acute and chronic SCI rodent models. Although clinical trials are currently under way, there is still debate about the organization of this supraspinal center and which anatomic correlate of the MLR should be targeted to promote recovery. Combining kinematics, electromyographic recordings, anatomic analysis, and mouse genetics, our study reveals that glutamatergic neurons of the cuneiform nucleus contribute to locomotor recovery by enhancing motor efficacy in hindlimb muscles, and by increasing locomotor rhythm and speed on a treadmill, over ground, and during swimming in chronic SCI mice. In contrast, glutamatergic neurons of the pedunculopontine nucleus slow down locomotion. Therefore, our study identifies the cuneiform nucleus and its glutamatergic neurons as a therapeutical target to improve locomotor recovery in patients living with SCI.
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Affiliation(s)
- Marie Roussel
- Centre de Recherche du CHU de Québec, CHUL-Neurosciences, 2705 Boul. Laurier, Québec, QC G1V 4G2, Canada
| | - David Lafrance-Zoubga
- Centre de Recherche du CHU de Québec, CHUL-Neurosciences, 2705 Boul. Laurier, Québec, QC G1V 4G2, Canada
| | - Nicolas Josset
- Centre de Recherche du CHU de Québec, CHUL-Neurosciences, 2705 Boul. Laurier, Québec, QC G1V 4G2, Canada
| | - Maxime Lemieux
- Centre de Recherche du CHU de Québec, CHUL-Neurosciences, 2705 Boul. Laurier, Québec, QC G1V 4G2, Canada
| | - Frederic Bretzner
- Centre de Recherche du CHU de Québec, CHUL-Neurosciences, 2705 Boul. Laurier, Québec, QC G1V 4G2, Canada; Faculty of Medicine, Department of Psychiatry and Neurosciences, Université Laval, Québec, QC G1V 4G2, Canada.
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12
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Brown AR, Mitra S, Teskey GC, Boychuk JA. Complex forelimb movements and cortical topography evoked by intracortical microstimulation in male and female mice. Cereb Cortex 2023; 33:1866-1875. [PMID: 35511684 PMCID: PMC9977357 DOI: 10.1093/cercor/bhac178] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 04/15/2022] [Accepted: 04/17/2022] [Indexed: 11/12/2022] Open
Abstract
The motor cortex is crucial for the voluntary control of skilled movement in mammals and is topographically organized into representations of the body (motor maps). Intracortical microstimulation of the motor cortex with long-duration pulse trains (LD-ICMS; ~500 ms) evokes complex movements, occurring in multiple joints or axial muscles, with characteristic movement postures and cortical topography across a variety of mammalian species. Although the laboratory mouse is extensively used in basic and pre-clinical research, high-resolution motor maps elicited with electrical LD-ICMS in both sexes of the adult mouse has yet to be reported. To address this knowledge gap, we performed LD-ICMS of the forelimb motor cortex in both male (n = 10) and naturally cycling female (n = 8) C57/BL6J mice under light ketamine-xylazine anesthesia. Complex and simple movements were evoked from historically defined caudal (CFA) and rostral (RFA) forelimb areas. Four complex forelimb movements were identified consisting of Elevate, Advance, Dig, and Retract postures with characteristic movement sequences and endpoints. Furthermore, evoked complex forelimb movements and cortical topography in mice were organized within the CFA in a unique manner relative to a qualitative comparison with the rat.
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Affiliation(s)
- Andrew R Brown
- Department of Cellular and Integrative Physiology, Joe R. & Teresa Lozano Long School of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA
| | - Shaarang Mitra
- Department of Cellular and Integrative Physiology, Joe R. & Teresa Lozano Long School of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA
| | - G Campbell Teskey
- Dept. of Cell Biology & Anatomy, Cumming School of Medicine, Calgary, Alberta T2N 4N1, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Jeffery A Boychuk
- Department of Cellular and Integrative Physiology, Joe R. & Teresa Lozano Long School of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA
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13
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Li GS, Chen GH, Wang KH, Wang XX, Hu XS, Wei B, Hu Y. Neurovascular Unit Compensation from Adjacent Level May Contribute to Spontaneous Functional Recovery in Experimental Cervical Spondylotic Myelopathy. Int J Mol Sci 2023; 24:ijms24043408. [PMID: 36834841 PMCID: PMC9962900 DOI: 10.3390/ijms24043408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 12/23/2022] [Accepted: 02/06/2023] [Indexed: 02/11/2023] Open
Abstract
The progression and remission of cervical spondylotic myelopathy (CSM) are quite unpredictable due to the ambiguous pathomechanisms. Spontaneous functional recovery (SFR) has been commonly implicated in the natural course of incomplete acute spinal cord injury (SCI), while the evidence and underlying pathomechanisms of neurovascular unit (NVU) compensation involved in SFR remains poorly understood in CSM. In this study, we investigate whether compensatory change of NVU, in particular in the adjacent level of the compressive epicenter, is involved in the natural course of SFR, using an established experimental CSM model. Chronic compression was created by an expandable water-absorbing polyurethane polymer at C5 level. Neurological function was dynamically assessed by BBB scoring and somatosensory evoked potential (SEP) up to 2 months. (Ultra)pathological features of NVUs were presented by histopathological and TEM examination. Quantitative analysis of regional vascular profile area/number (RVPA/RVPN) and neuroglial cells numbers were based on the specific EBA immunoreactivity and neuroglial biomarkers, respectively. Functional integrity of blood spinal cord barrier (BSCB) was detected by Evan blue extravasation test. Although destruction of the NVU, including disruption of the BSCB, neuronal degeneration and axon demyelination, as well as dramatic neuroglia reaction, were found in the compressive epicenter and spontaneous locomotor and sensory function recovery were verified in the modeling rats. In particular, restoration of BSCB permeability and an evident increase in RVPA with wrapping proliferated astrocytic endfeet in gray matter and neuron survival and synaptic plasticity were confirmed in the adjacent level. TEM findings also proved ultrastructural restoration of the NVU. Thus, NVU compensation changes in the adjacent level may be one of the essential pathomechanisms of SFR in CSM, which could be a promising endogenous target for neurorestoration.
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Affiliation(s)
- Guang-Sheng Li
- Spinal Division of Orthopedic and Traumatology Center, The Affiliated Hospital of Guangdong Medical University, Zhanjiang 524002, China
- Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong, China
| | - Guang-Hua Chen
- Spinal Division of Orthopedic and Traumatology Center, The Affiliated Hospital of Guangdong Medical University, Zhanjiang 524002, China
- Correspondence: (G.-H.C.); (Y.H.)
| | - Kang-Heng Wang
- Spinal Division of Orthopedic and Traumatology Center, The Affiliated Hospital of Guangdong Medical University, Zhanjiang 524002, China
| | - Xu-Xiang Wang
- Spinal Division of Orthopedic and Traumatology Center, The Affiliated Hospital of Guangdong Medical University, Zhanjiang 524002, China
| | - Xiao-Song Hu
- Spinal Division of Orthopedic and Traumatology Center, The Affiliated Hospital of Guangdong Medical University, Zhanjiang 524002, China
| | - Bo Wei
- Spinal Division of Orthopedic and Traumatology Center, The Affiliated Hospital of Guangdong Medical University, Zhanjiang 524002, China
| | - Yong Hu
- Spinal Division of Orthopedic and Traumatology Center, The Affiliated Hospital of Guangdong Medical University, Zhanjiang 524002, China
- Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong, China
- Correspondence: (G.-H.C.); (Y.H.)
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14
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Zelenin PV, Lyalka VF, Deliagina TG. Changes in operation of postural networks in rabbits with postural functions recovered after lateral hemisection of the spinal cord. J Physiol 2023; 601:307-334. [PMID: 36463517 PMCID: PMC9840688 DOI: 10.1113/jp283458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 11/30/2022] [Indexed: 12/07/2022] Open
Abstract
Acute lateral hemisection of the spinal cord (LHS) severely impairs postural functions, which recover over time. Here, to reveal changes in the operation of postural networks underlying the recovery, male rabbits with recovered postural functions after LHS at T12 (R-rabbits) were used. After decerebration, we characterized the responses of individual spinal interneurons from L5 along with hindlimb EMG responses to stimulation causing postural limb reflexes (PLRs) that substantially contribute to postural corrections in intact animals. The data were compared with those obtained in our previous studies of rabbits with the intact spinal cord and rabbits after acute LHS. Although, in R-rabbits, the EMG responses to postural disturbances both ipsilateral and contralateral to the LHS (ipsi-LHS and co-LHS) were only slightly distorted, PLRs on the co-LHS side (unaffected by acute LHS) were distorted substantially and PLRs on the ipsi-LHS side (abolished by acute LHS) were close to control. Thus, in R-rabbits, plastic changes develop in postural networks both affected and unaffected by acute LHS. PLRs on the ipsi-LHS side recover mainly as a result of changes at brainstem-cerebellum-spinal levels, whereas the forebrain is substantially involved in the generation of PLRs on the co-LHS side. We found that, in areas of grey matter in which the activity of spinal neurons of the postural network was significantly decreased after acute LHS, it recovered to the control level, whereas, in areas unaffected by acute LHS, it was significantly changed. These changes underlie the recovery and distortion of PLRs on the ipsi-LHS and co-LHS sides, respectively. KEY POINTS: After lateral hemisection of the spinal cord (LHS), postural functions recover over time. The underlying changes in the operation of postural networks are unknown. We compared the responses of individual spinal neurons and hindlimb muscles to stimulation causing postural limb reflexes (PLRs) in recovered LHS-rabbits with those obtained in rabbits with the intact spinal cord and rabbits after acute LHS. We demonstrated that changes underlying the recovery of postural functions take place not only in postural networks that are severely impaired, but also in those that are almost unaffected by acute LHS. PLRs on the LHS side recover mainly as a result of changes at brainstem-cerebellum-spinal levels, whereas the forebrain is substantially involved in the generation of PLRs contralateral to the LHS.
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Affiliation(s)
- Pavel V. Zelenin
- Department of Neuroscience Karolinska Institute Stockholm Sweden
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15
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Electroacupuncture-Regulated miR-34a-3p/PDCD6 Axis Promotes Post-Spinal Cord Injury Recovery in Both In Vitro and In Vivo Settings. J Immunol Res 2022; 2022:9329494. [PMID: 36132985 PMCID: PMC9484976 DOI: 10.1155/2022/9329494] [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] [Received: 07/02/2022] [Revised: 08/04/2022] [Accepted: 08/12/2022] [Indexed: 11/18/2022] Open
Abstract
Electroacupuncture (EA) could enhance neuroregeneration and posttraumatic conditions; however, the underlying regulatory mechanisms remain ambiguous. PDCD6 (programmed cell death 6) is an established proapoptotic regulator which is responsible for motoneuronal death. However, its potential regulatory role in post-spinal cord injury (SCI) regeneration has remained largely unknown. Further investigations are warranted to clarify the involvement of PDCD6 post-SCI recovery and the underlying mechanisms. In our study, based on bioinformatics prediction, we found that miR-34a-3p might be an upstream regulator miRNA for PDCD6, which was subsequently validated through combined utilization of the qRT-PCR, western blot, and dual-luciferase reporter system. Our in vitro results showed that miR-34a-3p might promote the in vitro differentiation of neural stem cell (NSC) through suppressing PDCD6 and regulating other important neural markers such as fibroblast growth factor receptor 1 (FGFR1), MAP1/2 (MAP kinase kinases 1/2), myelin basic protein (MBP), βIII-tubulin Class III β-tubulin (βIII tubulin), and glial fibrillary acidic protein (GFAP). Notably, in the post-SCI rat model, exogenous miR-34a-3p agomir obviously inhibited the expression of PDCD6 at the protein level and promoted neuronal proliferation, motoneurons regeneration, and axonal myelination. The restorations at cellular level might contribute to the improved hindlimbs functions of post-SCI rats, which was manifested by the Basso-Beattie-Bresnahan (BBB) locomotor test. The impact of miR-34a-3p was further promoted by EA treatment in vivo. Conclusively, this paper argues that a miR-34a-3p/PDCD6 axis might be a candidate therapeutic target for treating SCI and that the therapeutic effect of EA is driven through this pathway.
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16
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Rehabilitation on a treadmill induces plastic changes in the dendritic spines of spinal motoneurons associated with improved execution after a pharmacological injury to the motor cortex in rats. J Chem Neuroanat 2022; 125:102159. [PMID: 36087877 DOI: 10.1016/j.jchemneu.2022.102159] [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: 06/28/2022] [Revised: 09/01/2022] [Accepted: 09/02/2022] [Indexed: 11/22/2022]
Abstract
Lesions to the corticospinal tract result in several neurological symptoms and several rehabilitation protocols have proven useful in attempts to direct underlying plastic phenomena. However, the effects that such protocols may exert on the dendritic spines of motoneurons to enhance accuracy during rehabilitation are unknown. Thirty three female Sprague-Dawley adult rats were injected stereotaxically at the primary motor cerebral cortex (Fr1) with saline (CTL), or kainic acid (INJ), or kainic acid and further rehabilitation on a treadmill 16 days after lesion (INJ+RB). Motor performance was evaluated with the the Basso, Beatie and Bresnahan (BBB) locomotion scale and in the Rotarod. Spine density was quantified in a primary dendrite of motoneurons in Lamina IX in the ventral horn of the thoracolumbar spinal cord as well as spine morphology. AMPA, BDNF, PSD-95 and synaptophysin expression was evaluated by Western blot. INJ+RB group showed higher scores in motor performance. Animals from the INJ+RB group showed more thin, mushroom, stubby and wide spines than the CTL group, while the content of AMPA, BDNF, PSD-95 and Synaptophysin was not different between the groups INJ+RB and CTL. AMPA and synaptophysin content was greater in INJ group than in CTL and INJ+RB groups. The increase in the proportion of each type of spine observed in INJ+RB group suggest spinogenesis and a greater capability to integrate the afferent information to motoneurons under relatively stable molecular conditions at the synaptic level.
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17
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Xu Y, He X, Wang Y, Jian J, Peng X, Zhou L, Kang Y, Wang T. 5-Fluorouracil reduces the fibrotic scar via inhibiting matrix metalloproteinase 9 and stabilizing microtubules after spinal cord injury. CNS Neurosci Ther 2022; 28:2011-2023. [PMID: 35918897 PMCID: PMC9627390 DOI: 10.1111/cns.13930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 05/13/2022] [Accepted: 06/04/2022] [Indexed: 02/06/2023] Open
Abstract
AIMS Fibrotic scars composed of a dense extracellular matrix are the major obstacles for axonal regeneration. Previous studies have reported that antitumor drugs promote neurofunctional recovery. METHODS We investigated the effects of 5-fluorouracil (5-FU), a classical antitumor drug with a high therapeutic index, on fibrotic scar formation, axonal regeneration, and functional recovery after spinal cord injury (SCI). RESULTS 5-FU administration after hemisection SCI improved hind limb sensorimotor function of the ipsilateral hind paws. 5-FU application also significantly reduced the fibrotic scar formation labeled with aggrecan and fibronectin-positive components, Iba1+ /CD11b+ macrophages/microglia, vimentin, chondroitin sulfate proteoglycan 4 (NG2/CSPG4), and platelet-derived growth factor receptor beta (PDGFRβ)+ pericytes. Moreover, 5-FU treatment promoted stromal cells apoptosis and inhibited fibroblast proliferation and migration by abrogating the polarity of these cells and reducing matrix metalloproteinase 9 expression and promoted axonal growth of spinal neurons via the neuron-specific protein doublecortin-like kinase 1 (DCLK1). Therefore, 5-FU administration impedes the formation of fibrotic scars and promotes axonal regeneration to further restore sensorimotor function after SCI.
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Affiliation(s)
- Yang Xu
- Institute of Neurological Disease, West China Hospital, Sichuan University & The Research Units of West ChinaChinese Academy of Medical SciencesChengduChina,Laboratory of Anesthesia and Critical Care Medicine, Department of Anesthesiology, Translational Neuroscience Center, West China HospitalSichuan UniversityChengduChina
| | - Xiuying He
- Institute of Neurological Disease, West China Hospital, Sichuan University & The Research Units of West ChinaChinese Academy of Medical SciencesChengduChina,Laboratory of Anesthesia and Critical Care Medicine, Department of Anesthesiology, Translational Neuroscience Center, West China HospitalSichuan UniversityChengduChina
| | - Yangyang Wang
- Institute of Neurological Disease, West China Hospital, Sichuan University & The Research Units of West ChinaChinese Academy of Medical SciencesChengduChina
| | - Jiao Jian
- Institute of Neuroscience, Laboratory Zoology DepartmentKunming Medical UniversityKunmingChina
| | - Xia Peng
- Institute of Neuroscience, Laboratory Zoology DepartmentKunming Medical UniversityKunmingChina
| | - Lie Zhou
- Yunnan Key Laboratory of Stem Cell and Regenerative Medicine, Biomedical Engineering Research CenterKunming Medical UniversityKunmingChina
| | - Yi Kang
- Laboratory of Anesthesia and Critical Care Medicine, Department of Anesthesiology, Translational Neuroscience Center, West China HospitalSichuan UniversityChengduChina,National‐Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China HospitalSichuan UniversityChengduChina
| | - Tinghua Wang
- Institute of Neurological Disease, West China Hospital, Sichuan University & The Research Units of West ChinaChinese Academy of Medical SciencesChengduChina,Institute of Neuroscience, Laboratory Zoology DepartmentKunming Medical UniversityKunmingChina,National‐Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, West China HospitalSichuan UniversityChengduChina
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18
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Bao SS, Zhao C, Chen HW, Feng T, Guo XJ, Xu M, Rao JS. NT3 treatment alters spinal cord injury-induced changes in the gray matter volume of rhesus monkey cortex. Sci Rep 2022; 12:5919. [PMID: 35396344 PMCID: PMC8993853 DOI: 10.1038/s41598-022-09981-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 04/01/2022] [Indexed: 11/18/2022] Open
Abstract
Spinal cord injury (SCI) may cause structural alterations in brain due to pathophysiological processes, but the effects of SCI treatment on brain have rarely been reported. Here, voxel-based morphometry is employed to investigate the effects of SCI and neurotrophin-3 (NT3) coupled chitosan-induced regeneration on brain and spinal cord structures in rhesus monkeys. Possible association between brain and spinal cord structural alterations is explored. The pain sensitivity and stepping ability of animals are collected to evaluate sensorimotor functional alterations. Compared with SCI, the unique effects of NT3 treatment on brain structure appear in extensive regions which involved in motor control and neuropathic pain, such as right visual cortex, superior parietal lobule, left superior frontal gyrus (SFG), middle frontal gyrus, inferior frontal gyrus, insula, secondary somatosensory cortex, anterior cingulate cortex, and bilateral caudate nucleus. Particularly, the structure of insula is significantly correlated with the pain sensitivity. Regenerative treatment also shows a protective effect on spinal cord structure. The associations between brain and spinal cord structural alterations are observed in right primary somatosensory cortex, SFG, and other regions. These results help further elucidate secondary effects on brain of SCI and provide a basis for evaluating the effects of NT3 treatment on brain structure.
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Affiliation(s)
- Shu-Sheng Bao
- Beijing Key Laboratory for Biomaterials and Neural Regeneration, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Can Zhao
- Institute of Rehabilitation Engineering, China Rehabilitation Science Institute, Beijing, 100068, China. .,School of Rehabilitation, Capital Medical University, Beijing, 100068, China.
| | - Hao-Wei Chen
- Beijing Key Laboratory for Biomaterials and Neural Regeneration, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Ting Feng
- Beijing Key Laboratory for Biomaterials and Neural Regeneration, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Xiao-Jun Guo
- Beijing Key Laboratory for Biomaterials and Neural Regeneration, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China
| | - Meng Xu
- Department of Orthopedics, The First Medical Center of PLA General Hospital, Beijing, 100853, China.
| | - Jia-Sheng Rao
- Beijing Key Laboratory for Biomaterials and Neural Regeneration, Beijing Advanced Innovation Center for Biomedical Engineering, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China.
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19
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Martinez M. Targeting the motor cortex to restore walking after incomplete spinal cord injury. Neural Regen Res 2021; 17:1489-1490. [PMID: 34916428 PMCID: PMC8771094 DOI: 10.4103/1673-5374.330603] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- Marina Martinez
- Département de Neurosciences, Groupe de recherche sur la Signalisation Neurale et la Circuiterie and Centre Interdisciplinaire de Recherche sur le Cerveau au service de l'Apprentissage, Université de Montréal; CIUSSS du Nord-de-l'Île-de-Montréal, Montréal, QC, Canada
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20
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Lucas-Ruiz F, Galindo-Romero C, Albaladejo-García V, Vidal-Sanz M, Agudo-Barriuso M. Mechanisms implicated in the contralateral effect in the central nervous system after unilateral injury: focus on the visual system. Neural Regen Res 2021; 16:2125-2131. [PMID: 33818483 PMCID: PMC8354113 DOI: 10.4103/1673-5374.310670] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 11/21/2020] [Accepted: 01/11/2021] [Indexed: 12/21/2022] Open
Abstract
The retina, as part of the central nervous system is an ideal model to study the response of neurons to injury and disease and to test new treatments. During the last decade is becoming clear that unilateral lesions in bilateral areas of the central nervous system trigger an inflammatory response in the contralateral uninjured site. This effect has been better studied in the visual system where, as a rule, one retina is used as experimental and the other as control. Contralateral retinas in unilateral models of retinal injury show neuronal degeneration and glial activation. The mechanisms by which this adverse response in the central nervous system occurs are discussed in this review, focusing primarily on the visual system.
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Affiliation(s)
- Fernando Lucas-Ruiz
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria-Virgen de la Arrixaca (IMIBArrixaca) Murcia, Spain
| | - Caridad Galindo-Romero
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria-Virgen de la Arrixaca (IMIBArrixaca) Murcia, Spain
| | - Virginia Albaladejo-García
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria-Virgen de la Arrixaca (IMIBArrixaca) Murcia, Spain
| | - Manuel Vidal-Sanz
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria-Virgen de la Arrixaca (IMIBArrixaca) Murcia, Spain
| | - Marta Agudo-Barriuso
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia and Instituto Murciano de Investigación Biosanitaria-Virgen de la Arrixaca (IMIBArrixaca) Murcia, Spain
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21
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Castanov V, Berger MJ, Ritsma B, Trier J, Hendry JM. Optimizing the timing of peripheral nerve transfers for functional re-animation in cervical spinal cord injury: a conceptual framework. J Neurotrauma 2021; 38:3365-3375. [PMID: 34715742 DOI: 10.1089/neu.2021.0247] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Loss of upper extremity function following spinal cord injury (SCI) can have devastating consequences on quality of life. Peripheral nerve transfer surgery aims to restore motor control of upper extremities following cervical SCI and is poised to revolutionize surgical management in this population. The surgery involves dividing an expendable donor nerve above the level of the spinal lesion and coapting it to a recipient nerve arising from the lesional or infralesional segment of the injured cord. In order to maximize outcomes in this complex patient population, refinements in surgical technique need to be integrated with principles of spinal cord medicine and basic science. Deciding on the ideal timing of nerve transfer surgery is one aspect of care that is critical to maximizing recovery and has received very little attention to date in the literature. This complex topic is reviewed, with a focus on expectations for spontaneous recovery within upper motor neuron components of the injury, balanced against the need for expeditious reinnervation for lower motor neuron elements of the injury. The discussion also considers the case of a patient with C6 motor complete SCI where myotomes without electrodiagnostic evidence of denervation spontaneously improved by 6 months post-injury, thereby adjusting the surgical plan. The relevant concepts are integrated into a clinical algorithm with recommendations that consider maximal opportunity for spontaneous clinical improvement post-injury while avoiding excessive delays that may adversely affect patient outcomes.
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Affiliation(s)
- Valera Castanov
- Queen's University, 4257, School of Medicine, Kingston, Ontario, Canada;
| | - Michael James Berger
- The University of British Columbia, 8166, Division of Physical Medicine and Rehabilitation, Vancouver, British Columbia, Canada.,The University of British Columbia, 8166, International Collaboration on Repair Discoveries, Vancouver, British Columbia, Canada;
| | - Benjamin Ritsma
- Queen's University, 4257, Department of Physical Medicine and Rehabilitation, Kingston, Ontario, Canada.,Providence Care Hospital, 4256, Kingston, Ontario, Canada;
| | - Jessica Trier
- Queen's University, 4257, Department of Physical Medicine and Rehabilitation, Kingston, Ontario, Canada.,Providence Care Hospital, 4256, Kingston, Ontario, Canada;
| | - J Michael Hendry
- Queen's University, 4257, School of Medicine, Kingston, Ontario, Canada.,Queen's University, 4257, Division of Plastic Surgery, Department of Surgery, Kingston, Ontario, Canada.,Kingston Health Sciences Centre, 71459, Kingston, Ontario, Canada;
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22
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Corticospinal Motor Circuit Plasticity After Spinal Cord Injury: Harnessing Neuroplasticity to Improve Functional Outcomes. Mol Neurobiol 2021; 58:5494-5516. [PMID: 34341881 DOI: 10.1007/s12035-021-02484-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 07/07/2021] [Indexed: 10/20/2022]
Abstract
Spinal cord injury (SCI) is a devastating condition that affects approximately 294,000 people in the USA and several millions worldwide. The corticospinal motor circuitry plays a major role in controlling skilled movements and in planning and coordinating movements in mammals and can be damaged by SCI. While axonal regeneration of injured fibers over long distances is scarce in the adult CNS, substantial spontaneous neural reorganization and plasticity in the spared corticospinal motor circuitry has been shown in experimental SCI models, associated with functional recovery. Beneficially harnessing this neuroplasticity of the corticospinal motor circuitry represents a highly promising therapeutic approach for improving locomotor outcomes after SCI. Several different strategies have been used to date for this purpose including neuromodulation (spinal cord/brain stimulation strategies and brain-machine interfaces), rehabilitative training (targeting activity-dependent plasticity), stem cells and biological scaffolds, neuroregenerative/neuroprotective pharmacotherapies, and light-based therapies like photodynamic therapy (PDT) and photobiomodulation (PMBT). This review provides an overview of the spontaneous reorganization and neuroplasticity in the corticospinal motor circuitry after SCI and summarizes the various therapeutic approaches used to beneficially harness this neuroplasticity for functional recovery after SCI in preclinical animal model and clinical human patients' studies.
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23
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Bonizzato M, Martinez M. An intracortical neuroprosthesis immediately alleviates walking deficits and improves recovery of leg control after spinal cord injury. Sci Transl Med 2021; 13:13/586/eabb4422. [PMID: 33762436 DOI: 10.1126/scitranslmed.abb4422] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 01/09/2021] [Indexed: 12/18/2022]
Abstract
Most rehabilitation interventions after spinal cord injury (SCI) only target the sublesional spinal networks, peripheral nerves, and muscles. However, mammalian locomotion is not a mere act of rhythmic pattern generation. Recovery of cortical control is essential for voluntary movement and modulation of gait. We developed an intracortical neuroprosthetic intervention to SCI, with the goal to condition cortical locomotor control. Neurostimulation delivered in phase coherence with ongoing locomotion immediately alleviated primary SCI deficits, such as leg dragging, in rats with incomplete SCI. Cortical neurostimulation achieved high fidelity and markedly proportional online control of leg trajectories in both healthy and SCI rats. Long-term neuroprosthetic training lastingly improved cortical control of locomotion, whereas short training held transient improvements. We performed longitudinal awake cortical motor mapping, unveiling that recovery of cortico-spinal transmission tightly parallels return of locomotor function in rats. These results advocate directly targeting the motor cortex in clinical neuroprosthetic approaches.
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Affiliation(s)
- Marco Bonizzato
- Department of Neurosciences and Groupe de recherche sur le système nerveux central (GRSNC), Université de Montréal, Montréal, Québec H3T 1N8, Canada.,CIUSSS du Nord-de-l'Île-de-Montréal, Montréal, Québec H4J 1C5, Canada
| | - Marina Martinez
- Department of Neurosciences and Groupe de recherche sur le système nerveux central (GRSNC), Université de Montréal, Montréal, Québec H3T 1N8, Canada. .,CIUSSS du Nord-de-l'Île-de-Montréal, Montréal, Québec H4J 1C5, Canada
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24
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Brown AR, Martinez M. Chronic inactivation of the contralesional hindlimb motor cortex after thoracic spinal cord hemisection impedes locomotor recovery in the rat. Exp Neurol 2021; 343:113775. [PMID: 34081986 DOI: 10.1016/j.expneurol.2021.113775] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 05/13/2021] [Accepted: 05/27/2021] [Indexed: 10/21/2022]
Abstract
After incomplete spinal cord injury (SCI), cortical plasticity is involved in hindlimb locomotor recovery. Nevertheless, whether cortical activity is required for motor map plasticity and recovery remains unresolved. Here, we combined a unilateral thoracic spinal cord injury (SCI) with a cortical inactivation protocol that uncovered a functional role of contralesional cortical activity in hindlimb recovery and ipsilesional map plasticity. In adult rats, left hindlimb paralysis was induced by sectioning half of the spinal cord at the thoracic level (hemisection) and we used a continuous infusion of muscimol (GABAA agonist, 10 mM, 0.11 µl/h) delivered via implanted osmotic pump (n = 9) to chronically inactivate the contralesional hindlimb motor cortex. Hemisected rats with saline infusion served as a SCI control group (n = 8), and intact rats with muscimol infusion served as an inactivation control group (n = 6). Locomotion was assessed in an open field, on a horizontal ladder, and on a treadmill prior to and for three weeks after hemisection. Cortical inactivation after hemisection significantly impeded hindlimb locomotor recovery in all tasks and specifically disrupted the ability of rats to generate proper flexion of the affected hindlimb during stepping compared to SCI controls, with no significant effect of inactivation in intact rats. Chronic and acute (n = 4) cortical inactivation after hemisection also significantly reduced the representation of the affected hindlimb in the ipsilesional motor cortex derived with intracortical microsimulation (ICMS). Our results provide evidence that residual activity in the contralesional hindlimb motor cortex after thoracic hemisection contributes to spontaneous locomotor recovery and map plasticity.
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Affiliation(s)
- Andrew R Brown
- Département de Neurosciences Groupe de recherche sur le système nerveux central (GRSNC) and Centre Interdisciplinaire de Recherche sur le Cerveau au service de l'Apprentissage (CIRCA), Université de Montréal, Québec, Canada; CIUSSS du Nord-de-l'Île-de-Montréal, Québec, Canada
| | - Marina Martinez
- Département de Neurosciences Groupe de recherche sur le système nerveux central (GRSNC) and Centre Interdisciplinaire de Recherche sur le Cerveau au service de l'Apprentissage (CIRCA), Université de Montréal, Québec, Canada; CIUSSS du Nord-de-l'Île-de-Montréal, Québec, Canada.
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25
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Colton GF, Cook AP, Nusbaum MP. Different microcircuit responses to comparable input from one versus both copies of an identified projection neuron. J Exp Biol 2020; 223:jeb228114. [PMID: 32820029 PMCID: PMC7648612 DOI: 10.1242/jeb.228114] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 08/13/2020] [Indexed: 12/19/2022]
Abstract
Neuronal inputs to microcircuits are often present as multiple copies of apparently equivalent neurons. Thus far, however, little is known regarding the relative influence on microcircuit output of activating all or only some copies of such an input. We examine this issue in the crab (Cancer borealis) stomatogastric ganglion, where the gastric mill (chewing) microcircuit is activated by modulatory commissural neuron 1 (MCN1), a bilaterally paired modulatory projection neuron. Both MCN1s contain the same co-transmitters, influence the same gastric mill microcircuit neurons, can drive the biphasic gastric mill rhythm, and are co-activated by all identified MCN1-activating pathways. Here, we determine whether the gastric mill microcircuit response is equivalent when stimulating one or both MCN1s under conditions where the pair are matched to collectively fire at the same overall rate and pattern as single MCN1 stimulation. The dual MCN1 stimulations elicited more consistently coordinated rhythms, and these rhythms exhibited longer phases and cycle periods. These different outcomes from single and dual MCN1 stimulation may have resulted from the relatively modest, and equivalent, firing rate of the gastric mill neuron LG (lateral gastric) during each matched set of stimulations. The LG neuron-mediated, ionotropic inhibition of the MCN1 axon terminals is the trigger for the transition from the retraction to protraction phase. This LG neuron influence on MCN1 was more effective during the dual stimulations, where each MCN1 firing rate was half that occurring during the matched single stimulations. Thus, equivalent individual- and co-activation of a class of modulatory projection neurons does not necessarily drive equivalent microcircuit output.
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Affiliation(s)
- Gabriel F Colton
- Department of Neuroscience, 211 Clinical Research Building, 415 Curie Boulevard, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Aaron P Cook
- Department of Neuroscience, 211 Clinical Research Building, 415 Curie Boulevard, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Michael P Nusbaum
- Department of Neuroscience, 211 Clinical Research Building, 415 Curie Boulevard, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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26
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Abstract
Spinal cord injury is associated with chronic sensorimotor deficits due to the interruption of ascending and descending tracts between the brain and spinal cord. Functional recovery after anatomically complete spinal cord injury is limited due to the lack of long-distance axonal regeneration of severed fibers in the adult central nervous system. Most spinal cord injuries in humans, however, are anatomically incomplete. Although restorative treatment options for spinal cord injury remain currently limited, research from experimental models of spinal cord injury have revealed a tremendous capability for both spontaneous and treatment-induced plasticity of the corticospinal system that supports functional recovery. We review recent advances in the understanding of corticospinal circuit plasticity after spinal cord injury and concentrate mainly on the hindlimb motor cortex, its corticospinal projections, and the role of spinal mechanisms that support locomotor recovery. First, we discuss plasticity that occurs at the level of motor cortex and the reorganization of cortical movement representations. Next, we explore downstream plasticity in corticospinal projections. We then review the role of spinal mechanisms in locomotor recovery. We conclude with a perspective on harnessing neuroplasticity with therapeutic interventions to promote functional recovery.
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Affiliation(s)
- Andrew R Brown
- Département de Neurosciences, Faculté de Médecine, Université de Montréal; Hôpital du Sacré-Coeur de Montréal (CIUSS-NIM), Montréal, Québec, Canada
| | - Marina Martinez
- Département de Neurosciences, Faculté de Médecine, Université de Montréal; Hôpital du Sacré-Coeur de Montréal (CIUSS-NIM), Montréal; Groupe de Recherche sur le Système Nerveux Central, Université de Montréal, Montréal, Québec, Canada
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