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Fan F, Yin T, Wu B, Zheng J, Deng J, Wu G, Hu S. The role of spinal neurons targeted by corticospinal neurons in central poststroke neuropathic pain. CNS Neurosci Ther 2024; 30:e14813. [PMID: 38887838 PMCID: PMC11183184 DOI: 10.1111/cns.14813] [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: 01/14/2024] [Revised: 05/15/2024] [Accepted: 06/03/2024] [Indexed: 06/20/2024] Open
Abstract
BACKGROUND Central poststroke pain (CPSP) is one of the primary sequelae following stroke, yet its underlying mechanisms are poorly understood. METHODS By lesioning the lateral thalamic nuclei, we first established a CPSP model that exhibits mechanical and thermal hypersensitivity. Innocuous mechanical stimuli following the thalamic lesion evoked robust neural activation in somatosensory corticospinal neurons (CSNs), as well as in the deep dorsal horn, where low threshold mechanosensory afferents terminate. In this study, we used viral-based mapping and intersectional functional manipulations to decipher the role of somatosensory CSNs and their spinal targets in the CPSP pathophysiology. RESULTS We first mapped the post-synaptic spinal targets of lumbar innervating CSNs using an anterograde trans-synaptic AAV1-based strategy and showed these spinal interneurons were activated by innocuous tactile stimuli post-thalamic lesion. Functionally, tetanus toxin-based chronic inactivation of spinal neurons targeted by CSNs prevented the development of CPSP. Consistently, transient chemogenetic silencing of these neurons alleviated established mechanical pain hypersensitivity and innocuous tactile stimuli evoked aversion linked to the CPSP. In contrast, chemogenetic activation of these neurons was insufficient to induce robust mechanical allodynia typically observed in the CPSP. CONCLUSION The CSNs and their spinal targets are required but insufficient for the establishment of CPSP hypersensitivity. Our study provided novel insights into the neural mechanisms underlying CPSP and potential therapeutic interventions to treat refractory central neuropathic pain conditions.
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Affiliation(s)
- Fenqqi Fan
- Department of Pain, Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghaiChina
| | - Tianze Yin
- Department of Pain, Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghaiChina
| | - Biwu Wu
- Department of Neurosurgery and Neurocritical Care, Huashan HospitalFudan UniversityShanghaiChina
| | - Jiajun Zheng
- Department of Neurosurgery and Neurocritical Care, Huashan HospitalFudan UniversityShanghaiChina
| | - Jiaojiao Deng
- Department of Neurosurgery and Neurocritical Care, Huashan HospitalFudan UniversityShanghaiChina
| | - Gang Wu
- Department of Neurosurgery and Neurocritical Care, Huashan HospitalFudan UniversityShanghaiChina
| | - Shukun Hu
- Department of Neurosurgery and Neurocritical Care, Huashan HospitalFudan UniversityShanghaiChina
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2
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Wu B, Yang L, Xi C, Yao H, Chen L, Fan F, Wu G, Du Z, Hu J, Hu S. Corticospinal-specific Shh overexpression in combination with rehabilitation promotes CST axonal sprouting and skilled motor functional recovery after ischemic stroke. Mol Neurobiol 2024; 61:2186-2196. [PMID: 37864058 DOI: 10.1007/s12035-023-03642-y] [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: 04/30/2023] [Accepted: 09/06/2023] [Indexed: 10/22/2023]
Abstract
Ischemic stroke often leads to permanent neurological impairments, largely due to limited neuroplasticity in adult central nervous system. Here, we first showed that the expression of Sonic Hedgehog (Shh) in corticospinal neurons (CSNs) peaked at the 2nd postnatal week, when corticospinal synaptogenesis occurs. Overexpression of Shh in adult CSNs did not affect motor functions and had borderline effects on promoting the recovery of skilled locomotion following ischemic stroke. In contrast, CSNs-specific Shh overexpression significantly enhanced the efficacy of rehabilitative training, resulting in robust axonal sprouting and synaptogenesis of corticospinal axons into the denervated spinal cord, along with significantly improved behavioral outcomes. Mechanistically, combinatory treatment led to additional mTOR activation in CSNs when compared to that evoked by rehabilitative training alone. Taken together, our study unveiled a role of Shh, a morphogen involved in early development, in enhancing neuroplasticity, which significantly improved the outcomes of rehabilitative training. These results thus provide novel insights into the design of combinatory treatment for stroke and traumatic central nervous system injuries.
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Affiliation(s)
- Biwu Wu
- Department of Neurosurgery and Neurocritical Care, Affiliated Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai, 200042, China
- National Center for Neurological Disorders, Shanghai, China
- Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, China
- Neurosurgical Institute of Fudan University, Shanghai, China
- Shanghai Clinical Medical Center of Neurosurgery, Shanghai, China
| | - Lei Yang
- Department of Neurosurgery and Neurocritical Care, Affiliated Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai, 200042, China
- National Center for Neurological Disorders, Shanghai, China
- Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, China
- Neurosurgical Institute of Fudan University, Shanghai, China
- Shanghai Clinical Medical Center of Neurosurgery, Shanghai, China
| | - Caihua Xi
- Department of Neurosurgery and Neurocritical Care, Affiliated Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai, 200042, China
- National Center for Neurological Disorders, Shanghai, China
- Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, China
- Neurosurgical Institute of Fudan University, Shanghai, China
- Shanghai Clinical Medical Center of Neurosurgery, Shanghai, China
| | - Haijun Yao
- Department of Neurosurgery and Neurocritical Care, Affiliated Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai, 200042, China
- National Center for Neurological Disorders, Shanghai, China
- Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, China
- Neurosurgical Institute of Fudan University, Shanghai, China
- Shanghai Clinical Medical Center of Neurosurgery, Shanghai, China
| | - Long Chen
- Department of Neurosurgery and Neurocritical Care, Affiliated Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai, 200042, China
- National Center for Neurological Disorders, Shanghai, China
- Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, China
- Neurosurgical Institute of Fudan University, Shanghai, China
- Shanghai Clinical Medical Center of Neurosurgery, Shanghai, China
| | - Fengqi Fan
- Pain Department of Yueyang Integrated Traditional Chinese and Western Medicine Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Gang Wu
- Department of Neurosurgery and Neurocritical Care, Affiliated Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai, 200042, China
- National Center for Neurological Disorders, Shanghai, China
- Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, China
- Neurosurgical Institute of Fudan University, Shanghai, China
- Shanghai Clinical Medical Center of Neurosurgery, Shanghai, China
| | - Zhouying Du
- Department of Neurosurgery and Neurocritical Care, Affiliated Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai, 200042, China
- National Center for Neurological Disorders, Shanghai, China
- Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, China
- Neurosurgical Institute of Fudan University, Shanghai, China
- Shanghai Clinical Medical Center of Neurosurgery, Shanghai, China
| | - Jin Hu
- Department of Neurosurgery and Neurocritical Care, Affiliated Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai, 200042, China
- National Center for Neurological Disorders, Shanghai, China
- Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, China
- Neurosurgical Institute of Fudan University, Shanghai, China
- Shanghai Clinical Medical Center of Neurosurgery, Shanghai, China
| | - Shukun Hu
- Department of Neurosurgery and Neurocritical Care, Affiliated Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai, 200042, China.
- National Center for Neurological Disorders, Shanghai, China.
- Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, China.
- Neurosurgical Institute of Fudan University, Shanghai, China.
- Shanghai Clinical Medical Center of Neurosurgery, Shanghai, China.
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Li F, Wei C, Huo S, Liu X, Du J. Noninvasive Brain Stimulation for Motor Dysfunction After Incomplete Spinal Cord Injury: A Systematic Review and Meta-analysis. Am J Phys Med Rehabil 2024; 103:53-61. [PMID: 37408131 DOI: 10.1097/phm.0000000000002311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/07/2023]
Abstract
OBJECTIVE We aimed to examine the effectiveness of noninvasive brain stimulation on motor dysfunction after incomplete spinal cord injury. METHODS The PubMed, Embase, and Cochrane Library were searched from the inception dates to April 30, 2022. Randomized controlled trials comparing the effects of noninvasive brain stimulation and sham stimulation on motor dysfunction in patients with incomplete spinal cord injury were included. Two reviewers performed the data extraction and assessed study quality using Cochrane Collaboration's Tool. The primary outcomes involved upper limb function, lower limb function, spasticity, and activities of daily living. They were analyzed using meta-analysis method and the results were reported as standardized mean difference with 95% confidence interval. RESULTS Fourteen studies involving 225 patients were included. Noninvasive brain stimulation reduced spasticity at the end of intervention (standardized mean difference = -0.68, 95% confidence interval = -1.32 to -0.03, P = 0.04) and 1-wk follow-up (standardized mean difference = -0.82, 95% confidence interval = -1.48 to -0.16, P = 0.02), but no beneficial effect at 1-mo follow-up (standardized mean difference = -0.32, 95% confidence interval = -1.06 to 0.42, P = 0.39). In addition, noninvasive brain stimulation also increased lower limb muscle strength at 1-mo follow-up (standardized mean difference = 0.69, 95% confidence interval = 0.11 to 1.28, P = 0.02). Other main outcomes were similar between groups. CONCLUSIONS Noninvasive brain stimulation can reduce spasticity, and the favorable effect can sustain for 1 wk after intervention. In addition, noninvasive brain stimulation can increase lower limb muscle strength at 1-mo follow-up.
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Affiliation(s)
- Fang Li
- From the Department of Rehabilitation Medicine, Xuanwu Hospital, Capital Medical University, Beijing, People's Republic of China (FL, SH, XL, JD); and School of Mathematics and Statistics, Beijing Jiaotong University, Beijing, People's Republic of China (CW)
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Lin X, Wang X, Zhang Y, Chu G, Liang J, Zhang B, Lu Y, Steward O, Luo J. Synergistic effect of chemogenetic activation of corticospinal motoneurons and physical exercise in promoting functional recovery after spinal cord injury. Exp Neurol 2023; 370:114549. [PMID: 37774765 DOI: 10.1016/j.expneurol.2023.114549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Revised: 09/06/2023] [Accepted: 09/25/2023] [Indexed: 10/01/2023]
Abstract
Single therapeutic interventions have not yet been successful in restoring function after spinal cord injury. Accordingly, combinatorial interventions targeting multiple factors may hold greater promise for achieving maximal functional recovery. In this study, we applied a combinatorial approach of chronic chemogenetic neuronal activation and physical exercise including treadmill running and forelimb training tasks to promote functional recovery. In a mouse model of cervical (C5) dorsal hemisection of the spinal cord, which transects almost all descending corticospinal tract axons, combining selective activation of corticospinal motoneurons (CMNs) by intersectional chemogenetics with physical exercise significantly promoted functional recovery evaluated by the grid walking test, grid hanging test, rotarod test, and single pellet-reaching tasks. Electromyography and histological analysis showed increased activation of forelimb muscles via chemogenetic stimuli, and a greater density of vGlut1+ innervation in spinal cord grey matter rostral to the injury, suggesting enhanced neuroplasticity and connectivity. Combined therapy also enhanced activation of mTOR signaling and reduced apoptosis in spinal motoneurons, Counts revealed increased numbers of detectable choline acetyltransferase-positive motoneurons in the ventral horn. Taken together, the findings from this study validate a novel combinatorial approach to enhance motor function after spinal cord injury.
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Affiliation(s)
- Xueling Lin
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Xiuping Wang
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yuejin Zhang
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Guangpin Chu
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Jingwen Liang
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Bin Zhang
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yisheng Lu
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
| | - Oswald Steward
- Reeve-Irvine Research Center, University of California Irvine School of Medicine, USA; Department of Anatomy & Neurobiology, University of California Irvine School of Medicine, USA; Department of Neurobiology & Behavior, University of California Irvine, USA; Department of Neurosurgery, University of California Irvine School of Medicine, USA.
| | - Juan Luo
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
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Unger RH, Lowe MJ, Beall EB, Bethoux F, Jones SE, Machado AG, Plow EB, Cunningham DA. Stimulation of the Premotor Cortex Enhances Interhemispheric Functional Connectivity in Association with Upper Limb Motor Recovery in Moderate-to-Severe Chronic Stroke. Brain Connect 2023; 13:453-463. [PMID: 36772802 PMCID: PMC10618814 DOI: 10.1089/brain.2022.0064] [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: 02/12/2023] Open
Abstract
Background: Transcranial direct current stimulation (tDCS) targeting the primary motor cortex is modestly effective for promoting upper-limb motor function following stroke. The premotor cortex (PMC) represents an alternative target based on its higher likelihood of survival and dense motor-network connections. Objective: The objective of this study was to determine whether ipsilesional PMC tDCS affects motor network functional connectivity (FC) in association with reduction in motor impairment, and to determine whether this relationship is influenced by baseline motor severity. Methods: Participants with chronic stroke were randomly assigned to receive active-PMC or sham-tDCS with rehabilitation for 5 weeks. Resting-state functional magnetic resonance imaging was acquired to characterize change in FC across motor-cortical regions. Results: Our results indicated that moderate-to-severe participants who received active-tDCS had greater increases in PMC-to-PMC interhemispheric FC compared to those who received sham; this increase was correlated with reduction in proximal motor impairment. There was also an increase in intrahemispheric dorsal premotor cortex-primary motor cortex FC across participants regardless of severity or tDCS group assignment; this increase was correlated with a reduction in proximal motor impairment in only the mild participants. Conclusions: Our findings have significance for developing targeted brain stimulation approaches. While participants with milder impairments may inherently recruit viable substrates within the ipsilesional hemisphere, stimulation of PMC may enhance interhemispheric FC in association with recovery in more impaired participants. Trial Registration: ClinicalTrials.gov Identifier: NCT01539096; Registration date: February 21, 2012.
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Affiliation(s)
- Robert H. Unger
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
- Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Mark J. Lowe
- Imaging Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Erik B. Beall
- Imaging Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Francois Bethoux
- Center for Neurological Restoration, Neurological Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | | | - Andre G. Machado
- Center for Neurological Restoration, Neurological Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Ela B. Plow
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
- Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - David A. Cunningham
- Department of Physical Medicine and Rehabilitation, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA
- Department of Physical Medicine and Rehabilitation, MetroHealth Medical Center, Cleveland, Ohio, USA
- Cleveland Functional Electrical Stimulation Center, Cleveland, Ohio, USA
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6
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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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7
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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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8
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Kondiles B, Murphy R, Widman A, Perlmutter S, Horner P. Cortical stimulation leads to shortened myelin sheaths and increased axonal branching in spared axons after cervical spinal cord injury. Glia 2023; 71:1947-1959. [PMID: 37096399 PMCID: PMC10649492 DOI: 10.1002/glia.24376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 03/28/2023] [Accepted: 04/02/2023] [Indexed: 04/26/2023]
Abstract
Neural activity and learning lead to myelin sheath plasticity in the intact central nervous system (CNS), but this plasticity has not been well-studied after CNS injury. In the context of spinal cord injury (SCI), demyelination occurs at the lesion site and natural remyelination of surviving axons can take months. To determine if neural activity modulates myelin and axon plasticity in the injured, adult CNS, we electrically stimulated the contralesional motor cortex at 10 Hz to drive neural activity in the corticospinal tract of rats with sub-chronic spinal contusion injuries. We quantified myelin and axonal characteristics by tracing corticospinal axons rostral to and at the lesion epicenter and identifying nodes of Ranvier by immunohistochemistry. Three weeks of daily stimulation induced very short myelin sheaths, axon branching, and thinner axons outside of the lesion zone, where remodeling has not previously been reported. Surprisingly, remodeling was particularly robust rostral to the injury which suggests that electrical stimulation can promote white matter plasticity even in areas not directly demyelinated by the contusion. Stimulation did not alter myelin or axons at the lesion site, which suggests that neuronal activity does not contribute to myelin remodeling near the injury in the sub-chronic period. These data are the first to demonstrate wide-scale remodeling of nodal and myelin structures of a mature, long-tract motor pathway in response to electrical stimulation. This finding suggests that neuromodulation promotes white matter plasticity in intact regions of pathways after injury and raises intriguing questions regarding the interplay between axonal and myelin plasticity.
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Affiliation(s)
- B.R. Kondiles
- Department of Physiology and Biophysics, University of Washington, 1705 NE Pacific St. Seattle, WA, 98105, USA
- Center for Neuroregeneration, Dept. of Neurosurgery, Houston Methodist Research Institute, 6670 Bertner, Houston, TX, 77030, USA
| | - R.L. Murphy
- Department of Physiology and Biophysics, University of Washington, 1705 NE Pacific St. Seattle, WA, 98105, USA
| | - A.J. Widman
- Department of Physiology and Biophysics, University of Washington, 1705 NE Pacific St. Seattle, WA, 98105, USA
| | - S.I. Perlmutter
- Department of Physiology and Biophysics, University of Washington, 1705 NE Pacific St. Seattle, WA, 98105, USA
| | - P.J. Horner
- Center for Neuroregeneration, Dept. of Neurosurgery, Houston Methodist Research Institute, 6670 Bertner, Houston, TX, 77030, USA
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Ren J, Lv Y, Tian Q, Sun L, Miao P, Yang X, Xu LX, Feng CX, Li M, Gu Q, Feng X, Ding X. Suppression of Microglial ERO1a Alleviates Inflammation and Enhances the Efficacy of Rehabilitative Training After Ischemic Stroke. Mol Neurobiol 2023:10.1007/s12035-023-03333-8. [PMID: 37100971 DOI: 10.1007/s12035-023-03333-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 03/28/2023] [Indexed: 04/28/2023]
Abstract
Microglia mediated inflammation plays a crucial role in cellular events and functional recovery post ischemic stroke. In the current study, we profiled the proteome changes of microglia treated with oxygen and glucose deprivation (OGD). Bioinformatics analysis identified that differentially expressed proteins (DEPs) were enriched in pathways associated with oxidate phosphorylation and mitochondrial respiratory chain at both 6h and 24h post OGD. We next focused on one validated target named endoplasmic reticulum oxidoreductase 1 alpha (ERO1a) to study its role in stroke pathophysiology. We showed that over-expression of microglial ERO1a exacerbated inflammation, cell apoptosis and behavioral outcomes post middle cerebral artery occlusion (MCAO). In contrast, suppression of microglial ERO1a significantly reduced activation of both microglia and astrocyte, along with cell apoptosis. Furthermore, knocking down microglial ERO1a improved the efficacy of rehabilitative training and enhanced the mTOR activity in spared corticospinal neurons. Our study provided novel insights into the identification of therapeutic targets and the design of rehabilitative protocols to treat ischemic stroke and other traumatic CNS injuries.
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Affiliation(s)
- Jing Ren
- Soochow Key Laboratory of Prevention and Treatment of Child Brain Injury, Children's Hospital of Soochow University, No.92 Zhongnanjie Road, Suzhou, 215025, Jiangsu, China
| | - Yuan Lv
- Department of Neonatology, Northern Jiangsu People's Hospital, Yangzhou, 225000, China
- Clinical Medical College, Yangzhou University, Northan Jiangsu People's Hospital, Yangzhou, 225000, China
| | - Qiuyan Tian
- Pediatrics Research Institute, Children's Hospital of Soochow University, Suzhou, 215025, China
| | - Li Sun
- Soochow Key Laboratory of Prevention and Treatment of Child Brain Injury, Children's Hospital of Soochow University, No.92 Zhongnanjie Road, Suzhou, 215025, Jiangsu, China
| | - Po Miao
- Soochow Key Laboratory of Prevention and Treatment of Child Brain Injury, Children's Hospital of Soochow University, No.92 Zhongnanjie Road, Suzhou, 215025, Jiangsu, China
| | - Xiaofeng Yang
- Soochow Key Laboratory of Prevention and Treatment of Child Brain Injury, Children's Hospital of Soochow University, No.92 Zhongnanjie Road, Suzhou, 215025, Jiangsu, China
| | - Li-Xiao Xu
- Pediatrics Research Institute, Children's Hospital of Soochow University, Suzhou, 215025, China
| | - Chen-Xi Feng
- Pediatrics Research Institute, Children's Hospital of Soochow University, Suzhou, 215025, China
| | - Mei Li
- Pediatrics Research Institute, Children's Hospital of Soochow University, Suzhou, 215025, China
| | - Qin Gu
- Department of Rehabilitation, Children's Hospital of Soochow University, Suzhou, 215025, China
| | - Xing Feng
- Soochow Key Laboratory of Prevention and Treatment of Child Brain Injury, Children's Hospital of Soochow University, No.92 Zhongnanjie Road, Suzhou, 215025, Jiangsu, China.
| | - Xin Ding
- Soochow Key Laboratory of Prevention and Treatment of Child Brain Injury, Children's Hospital of Soochow University, No.92 Zhongnanjie Road, Suzhou, 215025, Jiangsu, China.
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10
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Van Steenbergen V, Burattini L, Trumpp M, Fourneau J, Aljović A, Chahin M, Oh H, D’Ambra M, Bareyre FM. Coordinated neurostimulation promotes circuit rewiring and unlocks recovery after spinal cord injury. J Exp Med 2023; 220:e20220615. [PMID: 36571760 PMCID: PMC9794600 DOI: 10.1084/jem.20220615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 10/26/2022] [Accepted: 12/15/2022] [Indexed: 12/27/2022] Open
Abstract
Functional recovery after incomplete spinal cord injury depends on the effective rewiring of neuronal circuits. Here, we show that selective chemogenetic activation of either corticospinal projection neurons or intraspinal relay neurons alone led to anatomically restricted plasticity and little functional recovery. In contrast, coordinated stimulation of both supraspinal centers and spinal relay stations resulted in marked and circuit-specific enhancement of neuronal rewiring, shortened EMG latencies, and improved locomotor recovery.
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Affiliation(s)
- Valérie Van Steenbergen
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
| | - Laura Burattini
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
| | - Michelle Trumpp
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
| | - Julie Fourneau
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
| | - Almir Aljović
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
- Graduate School of Systemic Neurosciences, LMU Munich, Planegg-Martinsried, Germany
| | - Maryam Chahin
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
- Graduate School of Systemic Neurosciences, LMU Munich, Planegg-Martinsried, Germany
| | - Hanseul Oh
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
- Graduate School of Systemic Neurosciences, LMU Munich, Planegg-Martinsried, Germany
| | - Marta D’Ambra
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
| | - Florence M. Bareyre
- Institute of Clinical Neuroimmunology, University Hospital, LMU Munich, Munich, Germany
- Biomedical Center Munich (BMC), Faculty of Medicine, LMU Munich, Planegg-Martinsried, Germany
- Munich Cluster of Systems Neurology (SyNergy), LMU Munich, Munich, Germany
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11
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Buetefisch CM, Haut MW, Revill KP, Shaeffer S, Edwards L, Barany DA, Belagaje SR, Nahab F, Shenvi N, Easley K. Stroke Lesion Volume and Injury to Motor Cortex Output Determines Extent of Contralesional Motor Cortex Reorganization. Neurorehabil Neural Repair 2023; 37:119-130. [PMID: 36786394 PMCID: PMC10079613 DOI: 10.1177/15459683231152816] [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: 02/15/2023]
Abstract
BACKGROUND After stroke, increases in contralesional primary motor cortex (M1CL) activity and excitability have been reported. In pre-clinical studies, M1CL reorganization is related to the extent of ipsilesional M1 (M1IL) injury, but this has yet to be tested clinically. OBJECTIVES We tested the hypothesis that the extent of damage to the ipsilesional M1 and/or its corticospinal tract (CST) determines the magnitude of M1CL reorganization and its relationship to affected hand function in humans recovering from stroke. METHODS Thirty-five participants with a single subacute ischemic stroke affecting M1 or CST and hand paresis underwent MRI scans of the brain to measure lesion volume and CST lesion load. Transcranial magnetic stimulation (TMS) of M1IL was used to determine the presence of an electromyographic response (motor evoked potential (MEP+ and MEP-)). M1CL reorganization was determined by TMS applied to M1CL at increasing intensities. Hand function was quantified with the Jebsen Taylor Hand Function Test. RESULTS The extent of M1CL reorganization was related to greater lesion volume in the MEP- group, but not in the MEP+ group. Greater M1CL reorganization was associated with more impaired hand function in MEP- but not MEP+ participants. Absence of an MEP (MEP-), larger lesion volumes and higher lesion loads in CST, particularly in CST fibers originating in M1 were associated with greater impairment of hand function. CONCLUSIONS In the subacute post-stroke period, stroke volume and M1IL output determine the extent of M1CL reorganization and its relationship to affected hand function, consistent with pre-clinical evidence.ClinicalTrials.gov Identifier: NCT02544503.
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Affiliation(s)
- Cathrin M Buetefisch
- Department of Neurology, Emory University, Atlanta, GA, USA.,Department of Rehabilitation Medicine, Emory University, Atlanta, GA, USA
| | - Marc W Haut
- Department of Behavioral Medicine and Psychiatry, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV, USA.,Department of Neurology, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV, USA.,Department of Radiology, West Virginia University, Morgantown, WV, USA
| | - Kate P Revill
- Department of Psychology, Emory University, Atlanta, GA, USA
| | - Scott Shaeffer
- Department of Neurology, Emory University, Atlanta, GA, USA
| | - Lauren Edwards
- Department of Neurology, Emory University, Atlanta, GA, USA
| | | | - Samir R Belagaje
- Department of Neurology, Emory University, Atlanta, GA, USA.,Department of Rehabilitation Medicine, Emory University, Atlanta, GA, USA.,Marcus Stroke and Neuroscience Center, Grady Memorial Hospital, Atlanta, GA, USA
| | - Fadi Nahab
- Department of Neurology, Emory University, Atlanta, GA, USA
| | - Neeta Shenvi
- Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Kirk Easley
- Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, GA, USA
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12
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Pal A, Park H, Ramamurthy A, Asan AS, Bethea T, Johnkutty M, Carmel JB. Spinal cord associative plasticity improves forelimb sensorimotor function after cervical injury. Brain 2022; 145:4531-4544. [PMID: 36063483 PMCID: PMC10200304 DOI: 10.1093/brain/awac235] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 06/10/2022] [Accepted: 06/17/2022] [Indexed: 01/06/2023] Open
Abstract
Associative plasticity occurs when two stimuli converge on a common neural target. Previous efforts to promote associative plasticity have targeted cortex, with variable and moderate effects. In addition, the targeted circuits are inferred, rather than tested directly. In contrast, we sought to target the strong convergence between motor and sensory systems in the spinal cord. We developed spinal cord associative plasticity, precisely timed pairing of motor cortex and dorsal spinal cord stimulations, to target this interaction. We tested the hypothesis that properly timed paired stimulation would strengthen the sensorimotor connections in the spinal cord and improve recovery after spinal cord injury. We tested physiological effects of paired stimulation, the pathways that mediate it, and its function in a preclinical trial. Subthreshold spinal cord stimulation strongly augmented motor cortex evoked muscle potentials at the time they were paired, but only when they arrived synchronously in the spinal cord. This paired stimulation effect depended on both cortical descending motor and spinal cord proprioceptive afferents; selective inactivation of either of these pathways fully abrogated the paired stimulation effect. Spinal cord associative plasticity, repetitive pairing of these pathways for 5 or 30 min in awake rats, increased spinal excitability for hours after pairing ended. To apply spinal cord associative plasticity as therapy, we optimized the parameters to promote strong and long-lasting effects. This effect was just as strong in rats with cervical spinal cord injury as in uninjured rats, demonstrating that spared connections after moderate spinal cord injury were sufficient to support plasticity. In a blinded trial, rats received a moderate C4 contusive spinal cord injury. Ten days after injury, they were randomized to 30 min of spinal cord associative plasticity each day for 10 days or sham stimulation. Rats with spinal cord associative plasticity had significantly improved function on the primary outcome measure, a test of dexterity during manipulation of food, at 50 days after spinal cord injury. In addition, rats with spinal cord associative plasticity had persistently stronger responses to cortical and spinal stimulation than sham stimulation rats, indicating a spinal locus of plasticity. After spinal cord associative plasticity, rats had near normalization of H-reflex modulation. The groups had no difference in the rat grimace scale, a measure of pain. We conclude that spinal cord associative plasticity strengthens sensorimotor connections within the spinal cord, resulting in partial recovery of reflex modulation and forelimb function after moderate spinal cord injury. Since both motor cortex and spinal cord stimulation are performed routinely in humans, this approach can be trialled in people with spinal cord injury or other disorders that damage sensorimotor connections and impair dexterity.
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Affiliation(s)
- Ajay Pal
- Department of Orthopedics, Columbia University, New York, NY 10032, USA
| | - HongGeun Park
- Department of Orthopedics, Columbia University, New York, NY 10032, USA
| | - Aditya Ramamurthy
- Department of Orthopedics, Columbia University, New York, NY 10032, USA
| | - Ahmet S Asan
- Department of Orthopedics, Columbia University, New York, NY 10032, USA
| | - Thelma Bethea
- Department of Orthopedics, Columbia University, New York, NY 10032, USA
| | - Meenu Johnkutty
- Department of Orthopedics, Columbia University, New York, NY 10032, USA
| | - Jason B Carmel
- Department of Orthopedics, Columbia University, New York, NY 10032, USA
- Department of Neurology, Columbia University, New York, NY 10032, USA
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13
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Anderson MA, Squair JW, Gautier M, Hutson TH, Kathe C, Barraud Q, Bloch J, Courtine G. Natural and targeted circuit reorganization after spinal cord injury. Nat Neurosci 2022; 25:1584-1596. [PMID: 36396975 DOI: 10.1038/s41593-022-01196-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 10/05/2022] [Indexed: 11/18/2022]
Abstract
A spinal cord injury disrupts communication between the brain and the circuits in the spinal cord that regulate neurological functions. The consequences are permanent paralysis, loss of sensation and debilitating dysautonomia. However, the majority of circuits located above and below the injury remain anatomically intact, and these circuits can reorganize naturally to improve function. In addition, various neuromodulation therapies have tapped into these processes to further augment recovery. Emerging research is illuminating the requirements to reconstitute damaged circuits. Here, we summarize these natural and targeted reorganizations of circuits after a spinal cord injury. We also advocate for new concepts of reorganizing circuits informed by multi-omic single-cell atlases of recovery from injury. These atlases will uncover the molecular logic that governs the selection of 'recovery-organizing' neuronal subpopulations, and are poised to herald a new era in spinal cord medicine.
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Affiliation(s)
- Mark A Anderson
- NeuroX Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland.,Wyss Center for Bio and Neuroengineering, Geneva, Switzerland
| | - Jordan W Squair
- NeuroX Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland
| | - Matthieu Gautier
- NeuroX Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland
| | - Thomas H Hutson
- NeuroX Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland.,Wyss Center for Bio and Neuroengineering, Geneva, Switzerland
| | - Claudia Kathe
- NeuroX Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland
| | - Quentin Barraud
- NeuroX Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland
| | - Jocelyne Bloch
- NeuroX Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.,Defitech Center for Interventional Neurotherapies (NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland
| | - Grégoire Courtine
- NeuroX Institute, School of Life Sciences, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland. .,Department of Clinical Neuroscience, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland. .,Defitech Center for Interventional Neurotherapies (NeuroRestore), EPFL/CHUV/UNIL, Lausanne, Switzerland.
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14
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Restoring After Central Nervous System Injuries: Neural Mechanisms and Translational Applications of Motor Recovery. Neurosci Bull 2022; 38:1569-1587. [DOI: 10.1007/s12264-022-00959-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 06/29/2022] [Indexed: 11/06/2022] Open
Abstract
AbstractCentral nervous system (CNS) injuries, including stroke, traumatic brain injury, and spinal cord injury, are leading causes of long-term disability. It is estimated that more than half of the survivors of severe unilateral injury are unable to use the denervated limb. Previous studies have focused on neuroprotective interventions in the affected hemisphere to limit brain lesions and neurorepair measures to promote recovery. However, the ability to increase plasticity in the injured brain is restricted and difficult to improve. Therefore, over several decades, researchers have been prompted to enhance the compensation by the unaffected hemisphere. Animal experiments have revealed that regrowth of ipsilateral descending fibers from the unaffected hemisphere to denervated motor neurons plays a significant role in the restoration of motor function. In addition, several clinical treatments have been designed to restore ipsilateral motor control, including brain stimulation, nerve transfer surgery, and brain–computer interface systems. Here, we comprehensively review the neural mechanisms as well as translational applications of ipsilateral motor control upon rehabilitation after CNS injuries.
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15
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Mesquida-Veny F, Martínez-Torres S, Del Río JA, Hervera A. Genetic control of neuronal activity enhances axonal growth only on permissive substrates. Mol Med 2022; 28:97. [PMID: 35978278 PMCID: PMC9387030 DOI: 10.1186/s10020-022-00524-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 08/03/2022] [Indexed: 11/19/2022] Open
Abstract
Background Neural tissue has limited regenerative ability. To cope with that, in recent years a diverse set of novel tools has been used to tailor neurostimulation therapies and promote functional regeneration after axonal injuries. Method In this report, we explore cell-specific methods to modulate neuronal activity, including opto- and chemogenetics to assess the effect of specific neuronal stimulation in the promotion of axonal regeneration after injury. Results Opto- and chemogenetic stimulations of neuronal activity elicited increased in vitro neurite outgrowth in both sensory and cortical neurons, as well as in vivo regeneration in the sciatic nerve, but not after spinal cord injury. Mechanistically, inhibitory substrates such as chondroitin sulfate proteoglycans block the activity induced increase in axonal growth. Conclusions We found that genetic modulations of neuronal activity on both dorsal root ganglia and corticospinal motor neurons increase their axonal growth capacity but only on permissive environments. Supplementary Information The online version contains supplementary material available at 10.1186/s10020-022-00524-2.
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Affiliation(s)
- Francina Mesquida-Veny
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain.,Department of Cell Biology, Physiology and Immunology, University of Barcelona, Barcelona, Spain.,Network Centre of Biomedical Research of Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Ministry of Economy and Competitiveness, Madrid, Spain.,Institute of Neuroscience, University of Barcelona, Barcelona, Spain
| | - Sara Martínez-Torres
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain.,Department of Cell Biology, Physiology and Immunology, University of Barcelona, Barcelona, Spain.,Network Centre of Biomedical Research of Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Ministry of Economy and Competitiveness, Madrid, Spain.,Institute of Neuroscience, University of Barcelona, Barcelona, Spain
| | - José Antonio Del Río
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain.,Department of Cell Biology, Physiology and Immunology, University of Barcelona, Barcelona, Spain.,Network Centre of Biomedical Research of Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Ministry of Economy and Competitiveness, Madrid, Spain.,Institute of Neuroscience, University of Barcelona, Barcelona, Spain
| | - Arnau Hervera
- Molecular and Cellular Neurobiotechnology, Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain. .,Department of Cell Biology, Physiology and Immunology, University of Barcelona, Barcelona, Spain. .,Network Centre of Biomedical Research of Neurodegenerative Diseases (CIBERNED), Institute of Health Carlos III, Ministry of Economy and Competitiveness, Madrid, Spain. .,Institute of Neuroscience, University of Barcelona, Barcelona, Spain.
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16
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Sinopoulou E, Spejo AB, Roopnarine N, Burnside ER, Bartus K, De Winter F, McMahon SB, Bradbury EJ. Chronic muscle recordings reveal recovery of forelimb function in spinal injured female rats after cortical epidural stimulation combined with rehabilitation and chondroitinase ABC. J Neurosci Res 2022; 100:2055-2076. [PMID: 35916483 PMCID: PMC9544922 DOI: 10.1002/jnr.25111] [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: 08/10/2020] [Revised: 06/23/2022] [Accepted: 07/09/2022] [Indexed: 11/11/2022]
Abstract
Cervical level spinal cord injury (SCI) can severely impact upper limb muscle function, which is typically assessed in the clinic using electromyography (EMG). Here, we established novel preclinical methodology for EMG assessments of muscle function after SCI in awake freely moving animals. Adult female rats were implanted with EMG recording electrodes in bicep muscles and received bilateral cervical (C7) contusion injuries. Forelimb muscle activity was assessed by recording maximum voluntary contractions during a grip strength task and cortical motor evoked potentials in the biceps. We demonstrate that longitudinal recordings of muscle activity in the same animal are feasible over a chronic post-injury time course and provide a sensitive method for revealing post-injury changes in muscle activity. This methodology was utilized to investigate recovery of muscle function after a novel combination therapy. Cervical contused animals received intraspinal injections of a neuroplasticity-promoting agent (lentiviral-chondroitinase ABC) plus 11 weeks of cortical epidural electrical stimulation (3 h daily, 5 days/week) and behavioral rehabilitation (15 min daily, 5 days/week). Longitudinal monitoring of voluntary and evoked muscle activity revealed significantly increased muscle activity and upper limb dexterity with the combination treatment, compared to a single treatment or no treatment. Retrograde mapping of motor neurons innervating the biceps showed a predominant distribution across spinal segments C5-C8, indicating that treatment effects were likely due to neuroplastic changes in a mixture of intact and injured motor neurons. Thus, longitudinal assessments of muscle function after SCI correlate with skilled reach and grasp performance and reveal functional benefits of a novel combination therapy.
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Affiliation(s)
- Eleni Sinopoulou
- Institute of Psychiatry, Psychology & Neuroscience, King's College London, Regeneration Group, The Wolfson Centre for Age-Related Diseases, London, UK.,Department of Neuroscience, The Center for Neural Repair, University of California, San Diego, California, USA
| | - Aline Barroso Spejo
- Institute of Psychiatry, Psychology & Neuroscience, King's College London, Regeneration Group, The Wolfson Centre for Age-Related Diseases, London, UK
| | - Naomi Roopnarine
- Institute of Psychiatry, Psychology & Neuroscience, King's College London, Regeneration Group, The Wolfson Centre for Age-Related Diseases, London, UK
| | - Emily R Burnside
- Institute of Psychiatry, Psychology & Neuroscience, King's College London, Regeneration Group, The Wolfson Centre for Age-Related Diseases, London, UK
| | - Katalin Bartus
- Institute of Psychiatry, Psychology & Neuroscience, King's College London, Regeneration Group, The Wolfson Centre for Age-Related Diseases, London, UK
| | - Fred De Winter
- Laboratory for Neuroregeneration, Netherlands Institute for Neuroscience, Amsterdam, The Netherlands
| | - Stephen B McMahon
- Institute of Psychiatry, Psychology & Neuroscience, King's College London, Regeneration Group, The Wolfson Centre for Age-Related Diseases, London, UK
| | - Elizabeth J Bradbury
- Institute of Psychiatry, Psychology & Neuroscience, King's College London, Regeneration Group, The Wolfson Centre for Age-Related Diseases, London, UK
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17
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Hu S, Wu G, Wu B, Du Z, Zhang Y. Rehabilitative training paired with peripheral stimulation promotes motor recovery after ischemic cerebral stroke. Exp Neurol 2021; 349:113960. [PMID: 34953896 DOI: 10.1016/j.expneurol.2021.113960] [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: 08/03/2021] [Revised: 12/12/2021] [Accepted: 12/18/2021] [Indexed: 12/22/2022]
Abstract
Spontaneous recovery of ischemic stroke is very limited and often results in the loss of motor and sensory function. Till now, rehabilitative training is the most widely accepted therapy to improve long-term outcome. However, its effectiveness is often suboptimal, largely due to a sharp decline of neuroplasticity in adults. In this study, we hypothesized that a combination of proprioceptive stimulation and rehabilitative training will promote neuroplasticity and functional recovery post injury. To test this hypothesis, we first established a photothrombotic stroke model that lesions the hindlimb sensorimotor cortex. Next, we demonstrated that injecting Cre-dependent AAV-retro viruses into the dorsal column of PV-Cre mice achieves specific and efficient targeting of proprioceptors. With chemogenetics, this method enables chronic activation of proprioceptors. We then assessed effects of combinatorial treatment on motor and sensory functional recovery. Our results showed that pairing proprioceptive stimulation with rehabilitative training significantly promoted skilled motor, but not tactile sensory functional recovery. This further led to significant improvement when compared to rehabilitation training or proprioceptor stimulation alone. Mechanistically, combinatorial treatment promoted cortical layer V neuronal mTOR activity and sprouting of corticospinal axon into the area where proprioceptive afferents terminate in the denervated side of the spinal cord. Serving as a proof of principle, our study thus provided novel insights into the application of combining proprioceptive stimulation and rehabilitative training to improve functional recovery of ischemic stroke and other traumatic brain or spinal cord injuries.
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Affiliation(s)
- Shukun Hu
- Department of Neurosurgery, Affiliated Huashan Hospital, Fudan University, Shanghai, China; National Center for Neurological Disorders, Shanghai, China; Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, China; Neurosurgical Institute of Fudan University, Shanghai, China; Shanghai Clinical Medical Center of Neurosurgery, Shanghai, China
| | - Gang Wu
- Department of Neurosurgery, Affiliated Huashan Hospital, Fudan University, Shanghai, China; National Center for Neurological Disorders, Shanghai, China; Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, China; Neurosurgical Institute of Fudan University, Shanghai, China; Shanghai Clinical Medical Center of Neurosurgery, Shanghai, China
| | - Biwu Wu
- Department of Neurosurgery, Affiliated Huashan Hospital, Fudan University, Shanghai, China; National Center for Neurological Disorders, Shanghai, China; Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, China; Neurosurgical Institute of Fudan University, Shanghai, China; Shanghai Clinical Medical Center of Neurosurgery, Shanghai, China
| | - Zhouying Du
- Department of Neurosurgery, Affiliated Huashan Hospital, Fudan University, Shanghai, China; National Center for Neurological Disorders, Shanghai, China; Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, China; Neurosurgical Institute of Fudan University, Shanghai, China; Shanghai Clinical Medical Center of Neurosurgery, Shanghai, China
| | - Yi Zhang
- Department of Neurosurgery, Affiliated Huashan Hospital, Fudan University, Shanghai, China; National Center for Neurological Disorders, Shanghai, China; Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, China; Neurosurgical Institute of Fudan University, Shanghai, China; Shanghai Clinical Medical Center of Neurosurgery, Shanghai, China.
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18
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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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19
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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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20
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Sharif H, Alexander H, Azam A, Martin JH. Dual motor cortex and spinal cord neuromodulation improves rehabilitation efficacy and restores skilled locomotor function in a rat cervical contusion injury model. Exp Neurol 2021; 341:113715. [PMID: 33819448 PMCID: PMC10150584 DOI: 10.1016/j.expneurol.2021.113715] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 03/14/2021] [Accepted: 03/31/2021] [Indexed: 01/11/2023]
Abstract
Motor recovery after spinal cord injury is limited due to sparse descending pathway axons caudal to the injury. Rehabilitation is the primary treatment for paralysis in humans with SCI, but only produces modest functional recovery. Here, we determined if dual epidural motor cortex (M1) intermittent theta burst stimulation (iTBS) and cathodal transcutaneous spinal direct stimulation (tsDCS) enhances the efficacy of rehabilitation in improving motor function after cervical SCI. iTBS produces CST axon sprouting and tsDCS enhances M1-evoked spinal activity and muscle contractions after SCI. Rats were trained to perform the horizontal ladder task. Animals received a moderate midline C4 contusion, producing bilateral forelimb impairments. After 2 weeks, animals either received 10 days of iTBS+tsDCS or no stimulation; subsequently, all animals received 6 weeks of daily rehabilitation on the horizontal ladder task. Lesion size was not different in the two animal groups. Rehabilitation alone improved performance by a 22% reduction in skilled locomotion error rate, whereas stimulation+rehabilitation was markedly more effective (52%), and restored error rate to pre-injury levels. Stimulation+rehabilitation significantly increased CST axon length caudal to the injury and the amount of ventral horn label was positively correlated with functional improvement. The stimulation+rehabilitation group had significantly less proprioceptive afferent terminal labelling in the intermediate zone and fewer synapses on motoneurons . Afferent fiber terminal labeling was negatively correlated with motor recovery. Thus, the dual neuromodulation protocol promotes adaptive plasticity in corticospinal and proprioceptive afferents networks after contusion SCI, leading to enhanced rehabilitation efficacy and recovery of skilled locomotion.
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Affiliation(s)
- Hisham Sharif
- Department of Molecular, Cellular, and Biomedical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA
| | - Heather Alexander
- Department of Molecular, Cellular, and Biomedical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA
| | - Anika Azam
- Department of Molecular, Cellular, and Biomedical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA
| | - John H Martin
- Department of Molecular, Cellular, and Biomedical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA; Neuroscience Program, Graduate Center of the City University of New York, New York, NY, USA.
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21
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Cleland BT, Madhavan S. Ipsilateral motor pathways to the lower limb after stroke: Insights and opportunities. J Neurosci Res 2021; 99:1565-1578. [PMID: 33665910 DOI: 10.1002/jnr.24822] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 02/17/2021] [Indexed: 01/04/2023]
Abstract
Stroke-related damage to the crossed lateral corticospinal tract causes motor deficits in the contralateral (paretic) limb. To restore functional movement in the paretic limb, the nervous system may increase its reliance on ipsilaterally descending motor pathways, including the uncrossed lateral corticospinal tract, the reticulospinal tract, the rubrospinal tract, and the vestibulospinal tract. Our knowledge about the role of these pathways for upper limb motor recovery is incomplete, and even less is known about the role of these pathways for lower limb motor recovery. Understanding the role of ipsilateral motor pathways to paretic lower limb movement and recovery after stroke may help improve our rehabilitative efforts and provide alternate solutions to address stroke-related impairments. These advances are important because walking and mobility impairments are major contributors to long-term disability after stroke, and improving walking is a high priority for individuals with stroke. This perspective highlights evidence regarding the contributions of ipsilateral motor pathways from the contralesional hemisphere and spinal interneuronal pathways for paretic lower limb movement and recovery. This perspective also identifies opportunities for future research to expand our knowledge about ipsilateral motor pathways and provides insights into how this information may be used to guide rehabilitation.
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Affiliation(s)
- Brice T Cleland
- Brain Plasticity Lab, Department of Physical Therapy, College of Applied Health Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Sangeetha Madhavan
- Brain Plasticity Lab, Department of Physical Therapy, College of Applied Health Sciences, University of Illinois at Chicago, Chicago, IL, USA
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22
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Wu D, Jin Y, Shapiro TM, Hinduja A, Baas PW, Tom VJ. Chronic neuronal activation increases dynamic microtubules to enhance functional axon regeneration after dorsal root crush injury. Nat Commun 2020; 11:6131. [PMID: 33257677 PMCID: PMC7705672 DOI: 10.1038/s41467-020-19914-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 11/05/2020] [Indexed: 12/26/2022] Open
Abstract
After a dorsal root crush injury, centrally-projecting sensory axons fail to regenerate across the dorsal root entry zone (DREZ) to extend into the spinal cord. We find that chemogenetic activation of adult dorsal root ganglion (DRG) neurons improves axon growth on an in vitro model of the inhibitory environment after injury. Moreover, repeated bouts of daily chemogenetic activation of adult DRG neurons for 12 weeks post-crush in vivo enhances axon regeneration across a chondroitinase-digested DREZ into spinal gray matter, where the regenerating axons form functional synapses and mediate behavioral recovery in a sensorimotor task. Neuronal activation-mediated axon extension is dependent upon changes in the status of tubulin post-translational modifications indicative of highly dynamic microtubules (as opposed to stable microtubules) within the distal axon, illuminating a novel mechanism underlying stimulation-mediated axon growth. We have identified an effective combinatory strategy to promote functionally-relevant axon regeneration of adult neurons into the CNS after injury.
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Affiliation(s)
- Di Wu
- Department of Neurobiology and Anatomy, Marion Murray Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Ying Jin
- Department of Neurobiology and Anatomy, Marion Murray Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Tatiana M Shapiro
- Department of Neurobiology and Anatomy, Marion Murray Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Abhishek Hinduja
- Department of Neurobiology and Anatomy, Marion Murray Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Peter W Baas
- Department of Neurobiology and Anatomy, Marion Murray Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Veronica J Tom
- Department of Neurobiology and Anatomy, Marion Murray Spinal Cord Research Center, Drexel University College of Medicine, Philadelphia, PA, USA.
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23
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Diabetes Mellitus-Related Dysfunction of the Motor System. Int J Mol Sci 2020; 21:ijms21207485. [PMID: 33050583 PMCID: PMC7589125 DOI: 10.3390/ijms21207485] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 10/08/2020] [Accepted: 10/08/2020] [Indexed: 12/20/2022] Open
Abstract
Although motor deficits in humans with diabetic neuropathy have been extensively researched, its effect on the motor system is thought to be lesser than that on the sensory system. Therefore, motor deficits are considered to be only due to sensory and muscle impairment. However, recent clinical and experimental studies have revealed that the brain and spinal cord, which are involved in the motor control of voluntary movement, are also affected by diabetes. This review focuses on the most important systems for voluntary motor control, mainly the cortico-muscular pathways, such as corticospinal tract and spinal motor neuron abnormalities. Specifically, axonal damage characterized by the proximodistal phenotype occurs in the corticospinal tract and motor neurons with long axons, and the transmission of motor commands from the brain to the muscles is impaired. These findings provide a new perspective to explain motor deficits in humans with diabetes. Finally, pharmacological and non-pharmacological treatment strategies for these disorders are presented.
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24
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Jara JS, Agger S, Hollis ER. Functional Electrical Stimulation and the Modulation of the Axon Regeneration Program. Front Cell Dev Biol 2020; 8:736. [PMID: 33015031 PMCID: PMC7462022 DOI: 10.3389/fcell.2020.00736] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Accepted: 07/15/2020] [Indexed: 01/07/2023] Open
Abstract
Neural injury in mammals often leads to persistent functional deficits as spontaneous repair in the peripheral nervous system (PNS) is often incomplete, while endogenous repair mechanisms in the central nervous system (CNS) are negligible. Peripheral axotomy elicits growth-associated gene programs in sensory and motor neurons that can support reinnervation of peripheral targets given sufficient levels of debris clearance and proximity to nerve targets. In contrast, while damaged CNS circuitry can undergo a limited amount of sprouting and reorganization, this innate plasticity does not re-establish the original connectivity. The utility of novel CNS circuitry will depend on effective connectivity and appropriate training to strengthen these circuits. One method of enhancing novel circuit connectivity is through the use of electrical stimulation, which supports axon growth in both central and peripheral neurons. This review will focus on the effects of CNS and PNS electrical stimulation in activating axon growth-associated gene programs and supporting the recovery of motor and sensory circuits. Electrical stimulation-mediated neuroplasticity represents a therapeutically viable approach to support neural repair and recovery. Development of appropriate clinical strategies employing electrical stimulation will depend upon determining the underlying mechanisms of activity-dependent axon regeneration and the heterogeneity of neuronal subtype responses to stimulation.
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Affiliation(s)
| | - Sydney Agger
- Burke Neurological Institute, White Plains, NY, United States
| | - Edmund R Hollis
- Burke Neurological Institute, White Plains, NY, United States.,Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, United States
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25
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Latchoumane CFV, Barany DA, Karumbaiah L, Singh T. Neurostimulation and Reach-to-Grasp Function Recovery Following Acquired Brain Injury: Insight From Pre-clinical Rodent Models and Human Applications. Front Neurol 2020; 11:835. [PMID: 32849253 PMCID: PMC7396659 DOI: 10.3389/fneur.2020.00835] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 07/06/2020] [Indexed: 12/26/2022] Open
Abstract
Reach-to-grasp is an evolutionarily conserved motor function that is adversely impacted following stroke and traumatic brain injury (TBI). Non-invasive brain stimulation (NIBS) methods, such as transcranial magnetic stimulation and transcranial direct current stimulation, are promising tools that could enhance functional recovery of reach-to-grasp post-brain injury. Though the rodent literature provides a causal understanding of post-injury recovery mechanisms, it has had a limited impact on NIBS protocols in human research. The high degree of homology in reach-to-grasp circuitry between humans and rodents further implies that the application of NIBS to brain injury could be better informed by findings from pre-clinical rodent models and neurorehabilitation research. Here, we provide an overview of the advantages and limitations of using rodent models to advance our current understanding of human reach-to-grasp function, cortical circuitry, and reorganization. We propose that a cross-species comparison of reach-to-grasp recovery could provide a mechanistic framework for clinically efficacious NIBS treatments that could elicit better functional outcomes for patients.
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Affiliation(s)
- Charles-Francois V. Latchoumane
- Department of Animal and Dairy Science, University of Georgia, Athens, GA, United States
- Regenerative Bioscience Center, University of Georgia, Athens, GA, United States
| | - Deborah A. Barany
- Department of Kinesiology, University of Georgia, Athens, GA, United States
| | - Lohitash Karumbaiah
- Department of Animal and Dairy Science, University of Georgia, Athens, GA, United States
- Regenerative Bioscience Center, University of Georgia, Athens, GA, United States
| | - Tarkeshwar Singh
- Regenerative Bioscience Center, University of Georgia, Athens, GA, United States
- Department of Kinesiology, University of Georgia, Athens, GA, United States
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26
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Frenkel-Toledo S, Ofir-Geva S, Soroker N. Lesion Topography Impact on Shoulder Abduction and Finger Extension Following Left and Right Hemispheric Stroke. Front Hum Neurosci 2020; 14:282. [PMID: 32765245 PMCID: PMC7379861 DOI: 10.3389/fnhum.2020.00282] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 06/23/2020] [Indexed: 11/13/2022] Open
Abstract
The existence of shoulder abduction and finger extension movement capacity shortly after stroke onset is an important prognostic factor, indicating favorable functional outcomes for the hemiparetic upper limb (HUL). Here, we asked whether variation in lesion topography affects these two movements similarly or distinctly and whether lesion impact is similar or distinct for left and right hemisphere damage. Shoulder abduction and finger extension movements were examined in 77 chronic post-stroke patients using relevant items of the Fugl-Meyer test. Lesion effects were analyzed separately for left and right hemispheric damage patient groups, using voxel-based lesion-symptom mapping. In the left hemispheric damage group, shoulder abduction and finger extension were affected only by damage to the corticospinal tract in its passage through the corona radiata. In contrast, following the right hemispheric damage, these two movements were affected not only by corticospinal tract damage but also by damage to white matter association tracts, the putamen, and the insular cortex. In both groups, voxel clusters have been found where damage affected shoulder abduction and also finger extension, along with voxels where damage affected only one of the two movements. The capacity to execute shoulder abduction and finger extension movements following stroke is affected significantly by damage to shared and distinct voxels in the corticospinal tract in left-hemispheric damage patients and by damage to shared and distinct voxels in a larger array of cortical and subcortical regions in right hemispheric damage patients.
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Affiliation(s)
- Silvi Frenkel-Toledo
- Department of Physical Therapy, School of Health Sciences, Ariel University, Ariel, Israel.,Department of Neurological Rehabilitation, Loewenstein Rehabilitation Hospital, Raanana, Israel
| | - Shay Ofir-Geva
- Department of Neurological Rehabilitation, Loewenstein Rehabilitation Hospital, Raanana, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Nachum Soroker
- Department of Neurological Rehabilitation, Loewenstein Rehabilitation Hospital, Raanana, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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27
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Jack AS, Hurd C, Martin J, Fouad K. Electrical Stimulation as a Tool to Promote Plasticity of the Injured Spinal Cord. J Neurotrauma 2020; 37:1933-1953. [PMID: 32438858 DOI: 10.1089/neu.2020.7033] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Unlike their peripheral nervous system counterparts, the capacity of central nervous system neurons and axons for regeneration after injury is minimal. Although a myriad of therapies (and different combinations thereof) to help promote repair and recovery after spinal cord injury (SCI) have been trialed, few have progressed from bench-top to bedside. One of the few such therapies that has been successfully translated from basic science to clinical applications is electrical stimulation (ES). Although the use and study of ES in peripheral nerve growth dates back nearly a century, only recently has it started to be used in a clinical setting. Since those initial experiments and seminal publications, the application of ES to restore function and promote healing have greatly expanded. In this review, we discuss the progression and use of ES over time as it pertains to promoting axonal outgrowth and functional recovery post-SCI. In doing so, we consider four major uses for the study of ES based on the proposed or documented underlying mechanism: (1) using ES to introduce an electric field at the site of injury to promote axonal outgrowth and plasticity; (2) using spinal cord ES to activate or to increase the excitability of neuronal networks below the injury; (3) using motor cortex ES to promote corticospinal tract axonal outgrowth and plasticity; and (4) leveraging the timing of paired stimuli to produce plasticity. Finally, the use of ES in its current state in the context of human SCI studies is discussed, in addition to ongoing research and current knowledge gaps, to highlight the direction of future studies for this therapeutic modality.
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Affiliation(s)
- Andrew S Jack
- Department of Neurological Surgery, University of California San Francisco (UCSF), San Francisco, California, USA
| | - Caitlin Hurd
- Department of Physical Therapy, Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - John Martin
- Department of Molecular, Cellular, and Biomedical Sciences, City University of New York School of Medicine, and City University of New York Graduate Center, New York, New York, USA
| | - Karim Fouad
- Department of Physical Therapy, Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Alberta, Canada.,Neuroscience and Mental Health Institute, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
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28
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Fujiki M, Yee KM, Steward O. Non-invasive High Frequency Repetitive Transcranial Magnetic Stimulation (hfrTMS) Robustly Activates Molecular Pathways Implicated in Neuronal Growth and Synaptic Plasticity in Select Populations of Neurons. Front Neurosci 2020; 14:558. [PMID: 32612497 PMCID: PMC7308563 DOI: 10.3389/fnins.2020.00558] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 05/06/2020] [Indexed: 12/21/2022] Open
Abstract
Patterns of neuronal activity that induce synaptic plasticity and memory storage activate kinase cascades in neurons that are thought to be part of the mechanism for synaptic modification. One such cascade involves induction of phosphorylation of ribosomal protein S6 in neurons due to synaptic activation of AKT/mTOR and via a different pathway, activation of MAP kinase/ERK1/2. Here, we show that phosphorylation of ribosomal protein S6 can also be strongly activated by high frequency repetitive transcranial magnetic stimulation (hfrTMS). HfrTMS was delivered to lightly anesthetized rats using a stimulation protocol that is a standard for inducing LTP in the perforant path in vivo (trains of 8 pulses at 400 Hz repeated at intervals of 1/10 s). Stimulation produced stimulus-locked motor responses but did not elicit behavioral seizures either during or after stimulation. After as little as 10 min of hfrTMS, immunostaining using phospho-specific antibodies for the phosphorylated form of ribosomal protein S6 (rpS6) revealed robust induction of rpS6 phosphorylation in large numbers of neurons in the cortex, especially the piriform cortex, and also in thalamic relay nuclei. Quantification revealed that the extent of the increased immunostaining depended on the number of trains and stimulus intensity. Of note, immunostaining for the immediate early genes Arc and c-fos revealed strong induction of IEG expression in many of the same populations of neurons throughout the cortex, but not the thalamus. These results indicate that hfrTMS can robustly activate molecular pathways critical for plasticity, which may contribute to the beneficial effects of TMS on recovery following brain and spinal cord injury and symptom amelioration in human psychiatric disorders. These molecular processes may be a useful surrogate marker to allow optimization of TMS parameters for maximal therapeutic benefit.
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Affiliation(s)
- Minoru Fujiki
- Department of Neurosurgery, School of Medicine, Oita University, Oita, Japan
| | - Kelly Matsudaira Yee
- Reeve-Irvine Research Center, University of California, Irvine, Irvine, CA, United States.,Department of Anatomy and Neurobiology, University of California, Irvine, Irvine, CA, United States.,Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
| | - Oswald Steward
- Reeve-Irvine Research Center, University of California, Irvine, Irvine, CA, United States.,Department of Anatomy and Neurobiology, University of California, Irvine, Irvine, CA, United States.,Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
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29
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Bao SC, Khan A, Song R, Kai-yu Tong R. Rewiring the Lesioned Brain: Electrical Stimulation for Post-Stroke Motor Restoration. J Stroke 2020; 22:47-63. [PMID: 32027791 PMCID: PMC7005350 DOI: 10.5853/jos.2019.03027] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 01/03/2020] [Accepted: 01/06/2020] [Indexed: 02/06/2023] Open
Abstract
Electrical stimulation has been extensively applied in post-stroke motor restoration, but its treatment mechanisms are not fully understood. Stimulation of neuromotor control system at multiple levels manipulates the corresponding neuronal circuits and results in neuroplasticity changes of stroke survivors. This rewires the lesioned brain and advances functional improvement. This review addresses the therapeutic mechanisms of different stimulation modalities, such as noninvasive brain stimulation, peripheral electrical stimulation, and other emerging techniques. The existing applications, the latest progress, and future directions are discussed. The use of electrical stimulation to facilitate post-stroke motor recovery presents great opportunities in terms of targeted intervention and easy applicability. Further technical improvements and clinical studies are required to reveal the neuromodulatory mechanisms and to enhance rehabilitation therapy efficiency in stroke survivors and people with other movement disorders.
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Affiliation(s)
- Shi-chun Bao
- Department of Biomedical Engineering, The Chinese University of Hong Kong, Hong Kong, China
| | - Ahsan Khan
- Department of Biomedical Engineering, The Chinese University of Hong Kong, Hong Kong, China
| | - Rong Song
- School of Biomedical Engineering, Sun Yat-Sen University, Guangzhou, China
| | - Raymond Kai-yu Tong
- Department of Biomedical Engineering, The Chinese University of Hong Kong, Hong Kong, China
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30
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Wu YK, Levine JM, Wecht JR, Maher MT, LiMonta JM, Saeed S, Santiago TM, Bailey E, Kastuar S, Guber KS, Yung L, Weir JP, Carmel JB, Harel NY. Posteroanterior cervical transcutaneous spinal stimulation targets ventral and dorsal nerve roots. Clin Neurophysiol 2019; 131:451-460. [PMID: 31887616 DOI: 10.1016/j.clinph.2019.11.056] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 10/24/2019] [Accepted: 11/17/2019] [Indexed: 12/13/2022]
Abstract
OBJECTIVE We aim to non-invasively facilitate activation of spared neural circuits after cervical spinal cord injury (SCI) and amyotrophic lateral sclerosis (ALS). We developed and tested a novel configuration for cervical transcutaneous spinal stimulation (cTSS). METHODS cTSS was delivered via electrodes placed over the midline at ~T2-T4 levels posteriorly and ~C4-C5 levels anteriorly. Electromyographic responses were measured in arm and hand muscles across a range of stimulus intensities. Double-pulse experiments were performed to assess homosynaptic post-activation depression (PAD). Safety was closely monitored. RESULTS More than 170 cTSS sessions were conducted without major safety or tolerability issues. A cathode-posterior, 2 ms biphasic waveform provided optimal stimulation characteristics. Bilateral upper extremity muscle responses were easily obtained in subjects with SCI and ALS. Resting motor threshold at the abductor pollicis brevis muscle ranged from 5.5 to 51.0 mA. As stimulus intensity increased, response latencies to all muscles decreased. PAD was incomplete at lower stimulus intensities, and decreased at higher stimulus intensities. CONCLUSIONS Posteroanterior cTSS has the capability to target motor neurons both trans-synaptically via large-diameter afferents and non-synaptically via efferent motor axons. SIGNIFICANCE Posteroanterior cTSS is well tolerated and easily activates upper extremity muscles in individuals with SCI and ALS.
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Affiliation(s)
- Yu-Kuang Wu
- James J. Peters VA Medical Center, 130 West Kingsbridge Road, Bronx, NY 10468, USA; Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, New York, NY 10029, USA
| | - Jonah M Levine
- James J. Peters VA Medical Center, 130 West Kingsbridge Road, Bronx, NY 10468, USA
| | - Jaclyn R Wecht
- James J. Peters VA Medical Center, 130 West Kingsbridge Road, Bronx, NY 10468, USA
| | - Matthew T Maher
- James J. Peters VA Medical Center, 130 West Kingsbridge Road, Bronx, NY 10468, USA
| | - James M LiMonta
- James J. Peters VA Medical Center, 130 West Kingsbridge Road, Bronx, NY 10468, USA
| | - Sana Saeed
- James J. Peters VA Medical Center, 130 West Kingsbridge Road, Bronx, NY 10468, USA
| | - Tiffany M Santiago
- James J. Peters VA Medical Center, 130 West Kingsbridge Road, Bronx, NY 10468, USA
| | - Eric Bailey
- James J. Peters VA Medical Center, 130 West Kingsbridge Road, Bronx, NY 10468, USA
| | - Shivani Kastuar
- Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, New York, NY 10029, USA
| | - Kenneth S Guber
- James J. Peters VA Medical Center, 130 West Kingsbridge Road, Bronx, NY 10468, USA
| | - Lok Yung
- James J. Peters VA Medical Center, 130 West Kingsbridge Road, Bronx, NY 10468, USA
| | - Joseph P Weir
- University of Kansas, 1301 Sunnyside Avenue, Lawrence, KS 66045, USA
| | - Jason B Carmel
- Columbia University, 650 West 168th Street, New York, NY 10032, USA
| | - Noam Y Harel
- James J. Peters VA Medical Center, 130 West Kingsbridge Road, Bronx, NY 10468, USA; Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, New York, NY 10029, USA.
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31
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Batty NJ, Torres-Espín A, Vavrek R, Raposo P, Fouad K. Single-session cortical electrical stimulation enhances the efficacy of rehabilitative motor training after spinal cord injury in rats. Exp Neurol 2019; 324:113136. [PMID: 31786212 DOI: 10.1016/j.expneurol.2019.113136] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 10/28/2019] [Accepted: 11/27/2019] [Indexed: 12/13/2022]
Abstract
Low neuronal cAMP levels in adults and a further decline following traumatic central nervous system (CNS) injury has been associated with the limited ability of neurons to regenerate. An approach to increase neuronal cAMP levels post injury is electrical stimulation. Stimulation as a tool to promote neuronal growth has largely been studied in the peripheral nervous system or in spared fibers of the CNS and this research suggests that a single session of electrical stimulation is sufficient to initiate a long-lasting axonal growth program. Here, we sought to promote plasticity and growth of the injured corticospinal tract with electrical cortical stimulation immediately after its spinal injury. Moreover, given the importance of rehabilitative motor training in the clinical setting and in translating plasticity into functional recovery, we applied training as a standard treatment to all rats (i.e., with or without electrical stimulation). Our findings show that electrical cortical stimulation did improve recovery in forelimb function compared to the recovery in unstimulated animals. This recovery is likely linked to increased corticospinal tract plasticity as evidenced by a significant increase in sprouting of collaterals above the lesion site, but not to increased regenerative growth through the lesion itself.
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Affiliation(s)
- Nicholas J Batty
- Neuroscience and Mental Health Institute, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Abel Torres-Espín
- Department of Physical Therapy, Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Romana Vavrek
- Department of Physical Therapy, Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Pamela Raposo
- Department of Physical Therapy, Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Alberta, Canada
| | - Karim Fouad
- Neuroscience and Mental Health Institute, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada; Department of Physical Therapy, Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Alberta, Canada.
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32
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Hutson TH, Di Giovanni S. The translational landscape in spinal cord injury: focus on neuroplasticity and regeneration. Nat Rev Neurol 2019; 15:732-745. [DOI: 10.1038/s41582-019-0280-3] [Citation(s) in RCA: 104] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/11/2019] [Indexed: 12/22/2022]
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33
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Yang Q, Ramamurthy A, Lall S, Santos J, Ratnadurai-Giridharan S, Lopane M, Zareen N, Alexander H, Ryan D, Martin JH, Carmel JB. Independent replication of motor cortex and cervical spinal cord electrical stimulation to promote forelimb motor function after spinal cord injury in rats. Exp Neurol 2019; 320:112962. [PMID: 31125548 PMCID: PMC7035596 DOI: 10.1016/j.expneurol.2019.112962] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 05/16/2019] [Accepted: 05/19/2019] [Indexed: 12/24/2022]
Abstract
Cervical spinal cord injury (SCI) impairs arm and hand function largely by interrupting descending tracts. Most SCI spare some axons at the lesion, including the corticospinal tract (CST), which is critical for voluntary movement. We targeted descending motor connections with paired electrical stimulation of motor cortex and cervical spinal cord in the rat. We sought to replicate the previously published effects of intermittent theta burst stimulation of forelimb motor cortex combined with trans-spinal direct current stimulation placed on the skin over the neck to target the cervical enlargement. We hypothesized that paired stimulation would improve performance in skilled walking and food manipulation (IBB) tasks. Rats received a moderate C4 spinal cord contusion injury (200 kDynes), which ablates the main CST. They were randomized to receive paired stimulation for 10 consecutive days starting 11 days after injury, or no stimulation. Behavior was assessed weekly from weeks 4-7 after injury, and then CST axons were traced. Rats with paired cortical and spinal stimulation achieved significantly better forelimb motor function recovery, as measured by fewer stepping errors on the horizontal ladder task (34 ± 9% in stimulation group vs. 51 ± 18% in control, p = .013) and higher scores on the food manipulation task (IBB, 0-9 score; 7.2 ± 0.8 in stimulated rats vs. 5.2 ± 2.6 in controls, p = .025). The effect size for both tasks was large (Cohen's d = 1.0 and 0.92, respectively). The CST axon length in the cervical spinal cord did not differ significantly between the groups, but there was denser and broader ipsilateral axons distribution distal to the spinal cord injury. The large behavioral effect and replication in an independent laboratory validate this approach, which will be trialed in cats before being tested in people using non-invasive methods.
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Affiliation(s)
- Qi Yang
- Departments of Neurology and Orthopedics, Columbia University, New York, NY 10031, USA
| | - Aditya Ramamurthy
- Departments of Neurology and Orthopedics, Columbia University, New York, NY 10031, USA
| | - Sophia Lall
- Burke Neurological Institute, Weill Cornell Medicine, White Plains, NY 10605, USA
| | - Joshua Santos
- Burke Neurological Institute, Weill Cornell Medicine, White Plains, NY 10605, USA
| | | | - Madeleine Lopane
- Burke Neurological Institute, Weill Cornell Medicine, White Plains, NY 10605, USA
| | - Neela Zareen
- Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA
| | - Heather Alexander
- Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA
| | - Daniel Ryan
- Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA
| | - John H Martin
- Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA; CUNY Graduate Center, New York, NY 10031, USA
| | - Jason B Carmel
- Departments of Neurology and Orthopedics, Columbia University, New York, NY 10031, USA.
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Dynamic Interaction between Cortico-Brainstem Pathways during Training-Induced Recovery in Stroke Model Rats. J Neurosci 2019; 39:7306-7320. [PMID: 31395620 DOI: 10.1523/jneurosci.0649-19.2019] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 07/22/2019] [Accepted: 07/31/2019] [Indexed: 11/21/2022] Open
Abstract
Reorganization of residual descending motor circuits underlies poststroke recovery. We previously clarified a causal relationship between the cortico-rubral tract and intensive limb use-induced functional recovery after internal capsule hemorrhage (ICH). However, other descending tracts, such as the cortico-reticular tract, might also be involved in rehabilitation-induced compensation. To investigate whether rehabilitation-induced recovery after ICH involves a shift in the compensatory circuit from the cortico-rubral tract to the cortico-reticular tract, we established loss of function of the cortico-rubral tract or/and cortico-reticular tract using two sets of viral vectors comprising the Tet-on system and designer receptors exclusively activated by the designer drug system. We used an ICH model that destroyed almost 60% of the corticofugal fibers. Anterograde tracing in rehabilitated rats revealed abundant sprouting of axons from the motor cortex in the red nucleus but not in the medullary reticular formation during the early phase of recovery. This primary contribution of the cortico-rubral tract was demonstrated by its selective blockade, whereas selective cortico-reticular tract silencing had little effect. Interestingly, cortico-rubral tract blockade from the start of rehabilitation induced an obvious increase of axon sprouting in the reticular formation with substantial functional recovery. Additional cortico-reticular tract silencing under the cortico-rubral tract blockade significantly worsened the recovered forelimb function. Furthermore, the alternative recruitment of the cortico-reticular tract was gradually induced by intensive limb use under cortico-rubral tract blockade, in which cortico-reticular tract silencing caused an apparent motor deficit. These findings indicate that individual cortico-brainstem pathways have dynamic compensatory potency to support rehabilitative functional recovery after ICH.SIGNIFICANCE STATEMENT This study aimed to clarify the interaction between the cortico-rubral and the cortico-reticular tract during intensive rehabilitation and functional recovery after capsular stroke. Pathway-selective disturbance by two sets of viral vectors revealed that the cortico-rubral tract was involved in rehabilitation-induced recovery of forelimb function from an early phase after internal capsule hemorrhage, but that the cortico-reticular tract was not. The sequential disturbance of both tracts revealed that the cortico-reticular tract was recruited and involved in rehabilitation-induced recovery when the cortico-rubral tract failed to function. Our data demonstrate a dynamic compensatory action of individual cortico-brainstem pathways for recovery through poststroke rehabilitation.
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Neuronal activity and microglial activation support corticospinal tract and proprioceptive afferent sprouting in spinal circuits after a corticospinal system lesion. Exp Neurol 2019; 321:113015. [PMID: 31326353 DOI: 10.1016/j.expneurol.2019.113015] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Revised: 05/12/2019] [Accepted: 07/17/2019] [Indexed: 12/17/2022]
Abstract
Spared corticospinal tract (CST) and proprioceptive afferent (PA) axons sprout after injury and contribute to rewiring spinal circuits, affecting motor recovery. Loss of CST connections post-injury results in corticospinal signal loss and associated reduction in spinal activity. We investigated the role of activity loss and injury on CST and PA sprouting. To understand activity-dependence after injury, we compared CST and PA sprouting after motor cortex (MCX) inactivation, produced by chronic MCX muscimol microinfusion, with sprouting after a CST lesion produced by pyramidal tract section (PTx). Activity suppression, which does not produce a lesion, is sufficient to trigger CST axon outgrowth from the active side to cross the midline and to enter the inactivated side of the spinal cord, to the same extent as PTx. Activity loss was insufficient to drive significant CST gray matter axon elongation, an effect of PTx. Activity suppression triggered presynaptic site formation, but less than PTx. Activity loss triggered PA sprouting, as PTx. To understand injury-dependent sprouting further, we blocked microglial activation and associated inflammation after PTX by chronic minocycline administration after PTx. Minocycline inhibited myelin debris phagocytosis contralateral to PTx and abolished CST axon elongation, formation of presynaptic sites, and PA sprouting, but not CST axon outgrowth from the active side to cross the midline. Our findings suggest sprouting after injury has a strong activity dependence and that microglial activation after injury supports axonal elongation and presynaptic site formation. Combining spinal activity support and inflammation control is potentially more effective in promoting functional restoration than either alone.
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A novel simplistic fabrication technique for cranial epidural electrodes for chronic recording and stimulation in rats. J Neurosci Methods 2019; 311:239-242. [PMID: 30389487 DOI: 10.1016/j.jneumeth.2018.10.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 09/18/2018] [Accepted: 10/29/2018] [Indexed: 01/02/2023]
Abstract
BACKGROUND The demand for neuromodulatory and recording tools has resulted in a surge of publications describing techniques for fabricating devices and accessories in-house suitable for neurological recordings. However, many of these fabrication protocols use equipment which are not common to biological laboratories, thus limiting researchers to the use of commercial alternatives. New method:We have developed a simple yet robust implantable stimulating surface electrode which can be fabricated in all wet-bench laboratories. RESULTS Female Sprague-Dawley rats received epidural implantation of the electrodes over the fore and hind limb areas of their motor cortex. Stimulation of the motor cortex successfully evoked fore- and hind limb motor outputs. The device was also able to record surface potentials of the motor cortex following epidural stimulation of the spinal cord. Comparisons with existing methods:For stimulation of the motor cortex, often stiff stainless or copper wires are roughly tucked underneath the skull, with little accuracy of localization. While, commercially available devices utilize burr holes and screw electrodes. Our new electrode design provides us stereotaxic accuracy that was not previously available. CONCLUSION We developed a chronic implantable electrode capable of being fabricated in all wet-labs, are robust, versatile and electrically sensitive enough for long-term chronic use. The simple and versatile electrode design provides scientific, economical and ethical benefits.
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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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Potter-Baker KA, Janini DP, Lin YL, Sankarasubramanian V, Cunningham DA, Varnerin NM, Chabra P, Kilgore KL, Richmond MA, Frost FS, Plow EB. Transcranial direct current stimulation (tDCS) paired with massed practice training to promote adaptive plasticity and motor recovery in chronic incomplete tetraplegia: A pilot study. J Spinal Cord Med 2018; 41:503-517. [PMID: 28784042 PMCID: PMC6117576 DOI: 10.1080/10790268.2017.1361562] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
OBJECTIVE Our goal was to determine if pairing transcranial direct current stimulation (tDCS) with rehabilitation for two weeks could augment adaptive plasticity offered by these residual pathways to elicit longer-lasting improvements in motor function in incomplete spinal cord injury (iSCI). DESIGN Longitudinal, randomized, controlled, double-blinded cohort study. SETTING Cleveland Clinic Foundation, Cleveland, Ohio, USA. PARTICIPANTS Eight male subjects with chronic incomplete motor tetraplegia. INTERVENTIONS Massed practice (MP) training with or without tDCS for 2 hrs, 5 times a week. OUTCOME MEASURES We assessed neurophysiologic and functional outcomes before, after and three months following intervention. Neurophysiologic measures were collected with transcranial magnetic stimulation (TMS). TMS measures included excitability, representational volume, area and distribution of a weaker and stronger muscle motor map. Functional assessments included a manual muscle test (MMT), upper extremity motor score (UEMS), action research arm test (ARAT) and nine hole peg test (NHPT). RESULTS We observed that subjects receiving training paired with tDCS had more increased strength of weak proximal (15% vs 10%), wrist (22% vs 10%) and hand (39% vs. 16%) muscles immediately and three months after intervention compared to the sham group. Our observed changes in muscle strength were related to decreases in strong muscle map volume (r=0.851), reduced weak muscle excitability (r=0.808), a more focused weak muscle motor map (r=0.675) and movement of weak muscle motor map (r=0.935). CONCLUSION Overall, our results encourage the establishment of larger clinical trials to confirm the potential benefit of pairing tDCS with training to improve the effectiveness of rehabilitation interventions for individuals with SCI. TRIAL REGISTRATION NCT01539109.
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Affiliation(s)
- Kelsey A. Potter-Baker
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA,Advanced Platform Technology Center, Louis Stokes Cleveland Department of Veteran’s Affairs, Cleveland, Ohio, USA
| | - Daniel P. Janini
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA
| | - Yin-Liang Lin
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA
| | | | - David A. Cunningham
- Kessler Foundation, Human Performance & Engineering Laboratory, West Orange, New Jersey, USA
| | - Nicole M. Varnerin
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA
| | - Patrick Chabra
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA
| | - Kevin L. Kilgore
- Functional Electrical Stimulation Center, Louis Stokes Cleveland Department of Veteran’s Affairs, Cleveland, Ohio, USA,Department of Orthopaedics, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA,Department of Orthopaedics, MetroHealth Medical Center, Cleveland, Ohio, USA
| | - Mary Ann Richmond
- Spinal Cord Injury and Disorders Service, Louis Stokes Cleveland Department of Veteran’s Affairs, Cleveland, Ohio, USA,Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA
| | - Frederick S. Frost
- Department of Physical Medicine and Rehabilitation, Neurological Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA
| | - Ela B. Plow
- Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA,Department of Physical Medicine and Rehabilitation, Neurological Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA,Center for Neurological Restoration, Neurosurgery, Neurological Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA,Correspondence to: Ela B. Plow Assistant Staff, Department of Biomedical Engineering, Assistant Professor, Cleveland Clinic Lerner College of Medicine, Cleveland Clinic Foundation, 9500 Euclid Ave., ND20 Cleveland, OH 44195, USA; Ph: 216-445-4589, Fax: 216-444-9198;
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Goss-Varley M, Shoffstall AJ, Dona KR, McMahon JA, Lindner SC, Ereifej ES, Capadona JR. Rodent Behavioral Testing to Assess Functional Deficits Caused by Microelectrode Implantation in the Rat Motor Cortex. J Vis Exp 2018:57829. [PMID: 30176008 PMCID: PMC6128113 DOI: 10.3791/57829] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Medical devices implanted in the brain hold tremendous potential. As part of a Brain Machine Interface (BMI) system, intracortical microelectrodes demonstrate the ability to record action potentials from individual or small groups of neurons. Such recorded signals have successfully been used to allow patients to interface with or control computers, robotic limbs, and their own limbs. However, previous animal studies have shown that a microelectrode implantation in the brain not only damages the surrounding tissue but can also result in functional deficits. Here, we discuss a series of behavioral tests to quantify potential motor impairments following the implantation of intracortical microelectrodes into the motor cortex of a rat. The methods for open field grid, ladder crossing, and grip strength testing provide valuable information regarding the potential complications resulting from a microelectrode implantation. The results of the behavioral testing are correlated with endpoint histology, providing additional information on the pathological outcomes and impacts of this procedure on the adjacent tissue.
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Affiliation(s)
- Monika Goss-Varley
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veterans Affairs Medical Center; Department of Biomedical Engineering, Case Western Reserve University
| | - Andrew J Shoffstall
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veterans Affairs Medical Center; Department of Biomedical Engineering, Case Western Reserve University
| | - Keith R Dona
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veterans Affairs Medical Center; Department of Biomedical Engineering, Case Western Reserve University
| | - Justin A McMahon
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veterans Affairs Medical Center; Department of Biomedical Engineering, Case Western Reserve University
| | - Sydney C Lindner
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veterans Affairs Medical Center; Department of Biomedical Engineering, Case Western Reserve University
| | - Evon S Ereifej
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veterans Affairs Medical Center; Department of Biomedical Engineering, Case Western Reserve University
| | - Jeffrey R Capadona
- Advanced Platform Technology Center, Rehabilitation Research and Development, Louis Stokes Cleveland Department of Veterans Affairs Medical Center; Department of Biomedical Engineering, Case Western Reserve University;
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State-of-the-Art Techniques to Causally Link Neural Plasticity to Functional Recovery in Experimental Stroke Research. Neural Plast 2018; 2018:3846593. [PMID: 29977279 PMCID: PMC5994266 DOI: 10.1155/2018/3846593] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 04/12/2018] [Accepted: 05/02/2018] [Indexed: 12/05/2022] Open
Abstract
Current experimental stroke research faces the same challenge as neuroscience: to transform correlative findings in causative ones. Research of recent years has shown the tremendous potential of the central nervous system to react to noxious stimuli such as a stroke: Increased plastic changes leading to reorganization in form of neuronal rewiring, neurogenesis, and synaptogenesis, accompanied by transcriptional and translational turnover in the affected cells, have been described both clinically and in experimental stroke research. However, only minor attempts have been made to connect distinct plastic remodeling processes as causative features for specific behavioral phenotypes. Here, we review current state-of the art techniques for the examination of cortical reorganization and for the manipulation of neuronal circuits as well as techniques which combine anatomical changes with molecular profiling. We provide the principles of the techniques together with studies in experimental stroke research which have already applied the described methodology. The tools discussed are useful to close the loop from our understanding of stroke pathology to the behavioral outcome and may allow discovering new targets for therapeutic approaches. The here presented methods open up new possibilities to assess the efficiency of rehabilitative strategies by understanding their external influence for intrinsic repair mechanisms on a neurobiological basis.
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Zareen N, Dodson S, Armada K, Awad R, Sultana N, Hara E, Alexander H, Martin JH. Stimulation-dependent remodeling of the corticospinal tract requires reactivation of growth-promoting developmental signaling pathways. Exp Neurol 2018; 307:133-144. [PMID: 29729248 DOI: 10.1016/j.expneurol.2018.05.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 03/18/2018] [Accepted: 05/01/2018] [Indexed: 12/13/2022]
Abstract
The corticospinal tract (CST) can become damaged after spinal cord injury or stroke, resulting in weakness or paralysis. Repair of the damaged CST is limited because mature CST axons fail to regenerate, which is partly because the intrinsic axon growth capacity is downregulated in maturity. Whereas CST axons sprout after injury, this is insufficient to recover lost functions. Chronic motor cortex (MCX) electrical stimulation is a neuromodulatory strategy to promote CST axon sprouting, leading to functional recovery after CST lesion. Here we examine the molecular mechanisms of stimulation-dependent CST axonal sprouting and synapse formation. MCX stimulation rapidly upregulates mTOR and Jak/Stat signaling in the corticospinal system. Chronic stimulation, which leads to CST sprouting and increased CST presynaptic sites, further enhances mTOR and Jak/Stat activity. Importantly, chronic stimulation shifts the equilibrium of the mTOR repressor PTEN to the inactive phosphorylated form suggesting a molecular transition to an axon growth state. We blocked each signaling pathway selectively to determine potential differential contributions to axonal outgrowth and synapse formation. mTOR blockade prevented stimulation-dependent axon sprouting. Surprisingly, Jak/Stat blockade did not abrogate sprouting, but instead prevented the increase in CST presynaptic sites produced by chronic MCX stimulation. Chronic stimulation increased the number of spinal neurons expressing the neural activity marker cFos. Jak/Stat blockade prevented the increase in cFos-expressing neurons after chronic stimulation, confirming an important role for Jak/Stat signaling in activity-dependent CST synapse formation. MCX stimulation is a neuromodulatory repair strategy that reactivates distinct developmentally-regulated signaling pathways for axonal outgrowth and synapse formation.
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Affiliation(s)
- Neela Zareen
- Department of Molecular, Cellular, and Basic Medical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA
| | - Shahid Dodson
- Department of Molecular, Cellular, and Basic Medical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA
| | - Kristine Armada
- Department of Molecular, Cellular, and Basic Medical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA
| | - Rahma Awad
- Department of Molecular, Cellular, and Basic Medical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA
| | - Nadia Sultana
- Department of Molecular, Cellular, and Basic Medical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA
| | - Erina Hara
- Department of Molecular, Cellular, and Basic Medical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA
| | - Heather Alexander
- Department of Molecular, Cellular, and Basic Medical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA
| | - John H Martin
- Department of Molecular, Cellular, and Basic Medical Sciences, Center for Discovery and Innovation, City University of New York School of Medicine, New York, NY, USA; Neuroscience Program, Graduate Center of the City University of New York, New York, NY, USA.
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Wen TC, Lall S, Pagnotta C, Markward J, Gupta D, Ratnadurai-Giridharan S, Bucci J, Greenwald L, Klugman M, Hill NJ, Carmel JB. Plasticity in One Hemisphere, Control From Two: Adaptation in Descending Motor Pathways After Unilateral Corticospinal Injury in Neonatal Rats. Front Neural Circuits 2018; 12:28. [PMID: 29706871 PMCID: PMC5906589 DOI: 10.3389/fncir.2018.00028] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 03/23/2018] [Indexed: 11/13/2022] Open
Abstract
After injury to the corticospinal tract (CST) in early development there is large-scale adaptation of descending motor pathways. Some studies suggest the uninjured hemisphere controls the impaired forelimb, while others suggest that the injured hemisphere does; these pathways have never been compared directly. We tested the contribution of each motor cortex to the recovery forelimb function after neonatal injury of the CST. We cut the left pyramid (pyramidotomy) of postnatal day 7 rats, which caused a measurable impairment of the right forelimb. We used pharmacological inactivation of each motor cortex to test its contribution to a skilled reach and supination task. Rats with neonatal pyramidotomy were further impaired by inactivation of motor cortex in both the injured and the uninjured hemispheres, while the forelimb of uninjured rats was impaired only from the contralateral motor cortex. Thus, inactivation demonstrated motor control from each motor cortex. In contrast, physiological and anatomical interrogation of these pathways support adaptations only in the uninjured hemisphere. Intracortical microstimulation of motor cortex in the uninjured hemisphere of rats with neonatal pyramidotomy produced responses from both forelimbs, while stimulation of the injured hemisphere did not elicit responses from either forelimb. Both anterograde and retrograde tracers were used to label corticofugal pathways. There was no increased plasticity from the injured hemisphere, either from cortex to the red nucleus or the red nucleus to the spinal cord. In contrast, there were very strong CST connections to both halves of the spinal cord from the uninjured motor cortex. Retrograde tracing produced maps of each forelimb within the uninjured hemisphere, and these were partly segregated. This suggests that the uninjured hemisphere may encode separate control of the unimpaired and the impaired forelimbs of rats with neonatal pyramidotomy.
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Affiliation(s)
- Tong-Chun Wen
- Motor Recovery Laboratory, Burke-Cornell Medical Research Institute, White Plains, NY, United States
| | - Sophia Lall
- Motor Recovery Laboratory, Burke-Cornell Medical Research Institute, White Plains, NY, United States
| | - Corey Pagnotta
- Motor Recovery Laboratory, Burke-Cornell Medical Research Institute, White Plains, NY, United States
| | - James Markward
- Motor Recovery Laboratory, Burke-Cornell Medical Research Institute, White Plains, NY, United States
| | - Disha Gupta
- Motor Recovery Laboratory, Burke-Cornell Medical Research Institute, White Plains, NY, United States
| | | | - Jacqueline Bucci
- Motor Recovery Laboratory, Burke-Cornell Medical Research Institute, White Plains, NY, United States
| | - Lucy Greenwald
- Motor Recovery Laboratory, Burke-Cornell Medical Research Institute, White Plains, NY, United States
| | - Madelyn Klugman
- Motor Recovery Laboratory, Burke-Cornell Medical Research Institute, White Plains, NY, United States
| | - N Jeremy Hill
- Motor Recovery Laboratory, Burke-Cornell Medical Research Institute, White Plains, NY, United States
| | - Jason B Carmel
- Motor Recovery Laboratory, Burke-Cornell Medical Research Institute, White Plains, NY, United States.,Departments of Neurology and Pediatrics, Brain and Mind Research Institute, Weill Cornell Medicine, Cornell University, New York, NY, United States
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An evaluation of the effect of pulse-shape on grey and white matter stimulation in the rat brain. Sci Rep 2018; 8:752. [PMID: 29335516 PMCID: PMC5768709 DOI: 10.1038/s41598-017-19023-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 12/15/2017] [Indexed: 01/22/2023] Open
Abstract
Despite the current success of neuromodulation, standard biphasic, rectangular pulse shapes may not be optimal to achieve symptom alleviation. Here, we compared stimulation efficiency (in terms of charge) between complex and standard pulses in two areas of the rat brain. In motor cortex, Gaussian and interphase gap stimulation (IPG) increased stimulation efficiency in terms of charge per phase compared with a standard pulse. Moreover, IPG stimulation of the deep mesencephalic reticular formation in freely moving rats was more efficient compared to a standard pulse. We therefore conclude that complex pulses are superior to standard stimulation, as less charge is required to achieve the same behavioral effects in a motor paradigm. These results have important implications for the understanding of electrical stimulation of the nervous system and open new perspectives for the design of the next generation of safe and efficient neural implants.
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Jack AS, Hurd C, Forero J, Nataraj A, Fenrich K, Blesch A, Fouad K. Cortical electrical stimulation in female rats with a cervical spinal cord injury to promote axonal outgrowth. J Neurosci Res 2017; 96:852-862. [DOI: 10.1002/jnr.24209] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 11/27/2017] [Accepted: 11/27/2017] [Indexed: 01/13/2023]
Affiliation(s)
- Andrew S. Jack
- Division of Neurosurgery, Department of Surgery, Faculty of Medicine and Dentistry; University of Alberta Hospital; Edmonton Alberta Canada
- Neuroscience and Mental Health Institute, Faculty of Medicine and Dentistry; University of Alberta; Edmonton Alberta Canada
| | - Caitlin Hurd
- Department of Physical Therapy, Faculty of Rehabilitation Medicine; University of Alberta; Edmonton Alberta Canada
| | - Juan Forero
- Department of Physical Therapy, Faculty of Rehabilitation Medicine; University of Alberta; Edmonton Alberta Canada
| | - Andrew Nataraj
- Division of Neurosurgery, Department of Surgery, Faculty of Medicine and Dentistry; University of Alberta Hospital; Edmonton Alberta Canada
- Neuroscience and Mental Health Institute, Faculty of Medicine and Dentistry; University of Alberta; Edmonton Alberta Canada
| | - Keith Fenrich
- Department of Physical Therapy, Faculty of Rehabilitation Medicine; University of Alberta; Edmonton Alberta Canada
| | - Armin Blesch
- Stark Neuroscience Research Institute; Indiana University; Indianapolis Indiana
| | - Karim Fouad
- Neuroscience and Mental Health Institute, Faculty of Medicine and Dentistry; University of Alberta; Edmonton Alberta Canada
- Department of Physical Therapy, Faculty of Rehabilitation Medicine; University of Alberta; Edmonton Alberta Canada
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Wahl AS, Büchler U, Brändli A, Brattoli B, Musall S, Kasper H, Ineichen BV, Helmchen F, Ommer B, Schwab ME. Optogenetically stimulating intact rat corticospinal tract post-stroke restores motor control through regionalized functional circuit formation. Nat Commun 2017; 8:1187. [PMID: 29084962 PMCID: PMC5662731 DOI: 10.1038/s41467-017-01090-6] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 08/17/2017] [Indexed: 11/18/2022] Open
Abstract
Current neuromodulatory strategies to enhance motor recovery after stroke often target large brain areas non-specifically and without sufficient understanding of their interaction with internal repair mechanisms. Here we developed a novel therapeutic approach by specifically activating corticospinal circuitry using optogenetics after large strokes in rats. Similar to a neuronal growth-promoting immunotherapy, optogenetic stimulation together with intense, scheduled rehabilitation leads to the restoration of lost movement patterns rather than induced compensatory actions, as revealed by a computer vision-based automatic behavior analysis. Optogenetically activated corticospinal neurons promote axonal sprouting from the intact to the denervated cervical hemi-cord. Conversely, optogenetically silencing subsets of corticospinal neurons in recovered animals, results in mistargeting of the restored grasping function, thus identifying the reestablishment of specific and anatomically localized cortical microcircuits. These results provide a conceptual framework to improve established clinical techniques such as transcranial magnetic or transcranial direct current stimulation in stroke patients. Existing methods to improve motor function after stroke include non-specific neuromodulatory approaches. Here the authors use an automated method of analysis of reaching behaviour in rodents to show that optogenetic stimulation of intact corticospinal tract fibres leads to restoration of prior motor functions, rather than compensatory acquisition of new movements.
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Affiliation(s)
- A S Wahl
- Brain Research Institute, University of Zurich, Winterthurerstr. 190, 8057, Zurich, Switzerland. .,Department of Health Sciences and Technology, ETH Zurich, Winterthurerstr. 190, 8057, Zurich, Switzerland. .,Central Institute of Mental Health, University of Heidelberg, J5, 68159, Mannheim, Germany.
| | - U Büchler
- Computer Vision Group, Interdisciplinary Center for Scientific Computing (IWR), University of Heidelberg, Mathematikon (INF 205), 69120, Heidelberg, Germany
| | - A Brändli
- Brain Research Institute, University of Zurich, Winterthurerstr. 190, 8057, Zurich, Switzerland.,Department of Health Sciences and Technology, ETH Zurich, Winterthurerstr. 190, 8057, Zurich, Switzerland
| | - B Brattoli
- Computer Vision Group, Interdisciplinary Center for Scientific Computing (IWR), University of Heidelberg, Mathematikon (INF 205), 69120, Heidelberg, Germany
| | - S Musall
- Brain Research Institute, University of Zurich, Winterthurerstr. 190, 8057, Zurich, Switzerland
| | - H Kasper
- Brain Research Institute, University of Zurich, Winterthurerstr. 190, 8057, Zurich, Switzerland
| | - B V Ineichen
- Brain Research Institute, University of Zurich, Winterthurerstr. 190, 8057, Zurich, Switzerland.,Department of Health Sciences and Technology, ETH Zurich, Winterthurerstr. 190, 8057, Zurich, Switzerland
| | - F Helmchen
- Brain Research Institute, University of Zurich, Winterthurerstr. 190, 8057, Zurich, Switzerland
| | - B Ommer
- Computer Vision Group, Interdisciplinary Center for Scientific Computing (IWR), University of Heidelberg, Mathematikon (INF 205), 69120, Heidelberg, Germany
| | - M E Schwab
- Brain Research Institute, University of Zurich, Winterthurerstr. 190, 8057, Zurich, Switzerland. .,Department of Health Sciences and Technology, ETH Zurich, Winterthurerstr. 190, 8057, Zurich, Switzerland.
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46
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Kondiles BR, Horner PJ. Myelin plasticity, neural activity, and traumatic neural injury. Dev Neurobiol 2017; 78:108-122. [PMID: 28925069 DOI: 10.1002/dneu.22540] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 09/01/2017] [Accepted: 09/14/2017] [Indexed: 12/12/2022]
Abstract
The possibility that adult organisms exhibit myelin plasticity has recently become a topic of great interest. Many researchers are exploring the role of myelin growth and adaptation in daily functions such as memory and motor learning. Here we consider evidence for three different potential categories of myelin plasticity: the myelination of previously bare axons, remodeling of existing sheaths, and the removal of a sheath with replacement by a new internode. We also review evidence that points to the importance of neural activity as a mechanism by which oligodendrocyte precursor cells (OPCs) are cued to differentiate into myelinating oligodendrocytes, which may potentially be an important component of myelin plasticity. Finally, we discuss demyelination in the context of traumatic neural injury and present an argument for altering neural activity as a potential therapeutic target for remyelination following injury. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 78: 108-122, 2018.
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Affiliation(s)
- Bethany R Kondiles
- Center for Neuroregeneration, Houston Methodist Research Institute, 6670 Bertner Avenue, MSR10-112, Houston, Texas.,Department of Physiology and Biophysics, University of Washington, Seattle, Washington
| | - Philip J Horner
- Center for Neuroregeneration, Houston Methodist Research Institute, 6670 Bertner Avenue, MSR10-112, Houston, Texas
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47
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Liu Y, Wang X, Li W, Zhang Q, Li Y, Zhang Z, Zhu J, Chen B, Williams PR, Zhang Y, Yu B, Gu X, He Z. A Sensitized IGF1 Treatment Restores Corticospinal Axon-Dependent Functions. Neuron 2017; 95:817-833.e4. [PMID: 28817801 DOI: 10.1016/j.neuron.2017.07.037] [Citation(s) in RCA: 134] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 05/23/2017] [Accepted: 07/28/2017] [Indexed: 01/07/2023]
Abstract
A major hurdle for functional recovery after both spinal cord injury and cortical stroke is the limited regrowth of the axons in the corticospinal tract (CST) that originate in the motor cortex and innervate the spinal cord. Despite recent advances in engaging the intrinsic mechanisms that control CST regrowth, it remains to be tested whether such methods can promote functional recovery in translatable settings. Here we show that post-lesional AAV-assisted co-expression of two soluble proteins, namely insulin-like growth factor 1 (IGF1) and osteopontin (OPN), in cortical neurons leads to robust CST regrowth and the recovery of CST-dependent behavioral performance after both T10 lateral spinal hemisection and a unilateral cortical stroke. In these mice, a compound able to increase axon conduction, 4-aminopyridine-3-methanol, promotes further improvement in CST-dependent behavioral tasks. Thus, our results demonstrate a potentially translatable strategy for restoring cortical dependent function after injury in the adult.
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Affiliation(s)
- Yuanyuan Liu
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Xuhua Wang
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Wenlei Li
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA; Department of Neurology, Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210004, China
| | - Qian Zhang
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA; Department of Neurobiology and Collaborative Innovation Center for Brain Science, Fourth Military Medical University, Xi'an 710032, China
| | - Yi Li
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Zicong Zhang
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Junjie Zhu
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Bo Chen
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Philip R Williams
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Yiming Zhang
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Bin Yu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China
| | - Xiaosong Gu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China
| | - Zhigang He
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA; Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.
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Zareen N, Shinozaki M, Ryan D, Alexander H, Amer A, Truong DQ, Khadka N, Sarkar A, Naeem S, Bikson M, Martin JH. Motor cortex and spinal cord neuromodulation promote corticospinal tract axonal outgrowth and motor recovery after cervical contusion spinal cord injury. Exp Neurol 2017; 297:179-189. [PMID: 28803750 DOI: 10.1016/j.expneurol.2017.08.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2017] [Revised: 08/04/2017] [Accepted: 08/09/2017] [Indexed: 01/15/2023]
Abstract
Cervical injuries are the most common form of SCI. In this study, we used a neuromodulatory approach to promote skilled movement recovery and repair of the corticospinal tract (CST) after a moderately severe C4 midline contusion in adult rats. We used bilateral epidural intermittent theta burst (iTBS) electrical stimulation of motor cortex to promote CST axonal sprouting and cathodal trans-spinal direct current stimulation (tsDCS) to enhance spinal cord activation to motor cortex stimulation after injury. We used Finite Element Method (FEM) modeling to direct tsDCS to the cervical enlargement. Combined iTBS-tsDCS was delivered for 30min daily for 10days. We compared the effect of stimulation on performance in the horizontal ladder and the Irvine Beattie and Bresnahan forepaw manipulation tasks and CST axonal sprouting in injury-only and injury+stimulation animals. The contusion eliminated the dorsal CST in all animals. tsDCS significantly enhanced motor cortex evoked responses after C4 injury. Using this combined spinal-M1 neuromodulatory approach, we found significant recovery of skilled locomotion and forepaw manipulation skills compared with injury-only controls. The spared CST axons caudal to the lesion in both animal groups derived mostly from lateral CST axons that populated the contralateral intermediate zone. Stimulation enhanced injury-dependent CST axonal outgrowth below and above the level of the injury. This dual neuromodulatory approach produced partial recovery of skilled motor behaviors that normally require integration of posture, upper limb sensory information, and intent for performance. We propose that the motor systems use these new CST projections to control movements better after injury.
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Affiliation(s)
- N Zareen
- Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA
| | - M Shinozaki
- Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA
| | - D Ryan
- Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA
| | - H Alexander
- Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA
| | - A Amer
- Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA; CUNY Graduate Center, New York, NY 10031, USA
| | - D Q Truong
- Department of Biomedical Engineering, City College of NY, 10031, USA
| | - N Khadka
- Department of Biomedical Engineering, City College of NY, 10031, USA
| | - A Sarkar
- Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA
| | - S Naeem
- Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA
| | - M Bikson
- Department of Biomedical Engineering, City College of NY, 10031, USA
| | - J H Martin
- Department of Molecular, Cellular, and Biomedical Sciences, City University of NY School of Medicine, New York, NY 10031, USA; CUNY Graduate Center, New York, NY 10031, USA.
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49
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Li Q, Houdayer T, Liu S, Belegu V. Induced Neural Activity Promotes an Oligodendroglia Regenerative Response in the Injured Spinal Cord and Improves Motor Function after Spinal Cord Injury. J Neurotrauma 2017; 34:3351-3361. [PMID: 28474539 DOI: 10.1089/neu.2016.4913] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
Myelination in the central nervous system (CNS) is a dynamic process that includes birth of oligodendrocyte progenitor cells (OPCs), their differentiation into oligodendrocytes, and ensheathment of axons. Regulation of myelination by neuronal activity has emerged as a new mechanism of CNS plasticity. Activity-dependent myelination has been shown to regulate sensory, motor, and cognitive functions. In this work, we aimed to employ this mechanism of CNS plasticity by utilizing induced neuronal activity to promote remyelination and functional recovery in a subchronic model of spinal cord injury (SCI). We used a mild contusive SCI at T10, which demyelinates surviving axons of the dorsal corticospinal tract (dCST), to investigate the effects of induced neuronal activity on oligodendrogenesis, remyelination, and motor function after SCI. Neuronal activity was induced through epidural electrodes that were implanted over the primary motor (M1) cortex. Induced neuronal activity increased the number of proliferating OPCs. Additionally, induced neuronal activity in the subchronic stages of SCI increased the number of oligodendrocytes, and enhanced myelin basic protein (MBP) expression and myelin sheath formation in dCST. The oligodendroglia regenerative response could have been mediated by axon-OPC synapses, the number of which increased after induced neuronal activity. Further, M1-induced neuronal activation promoted recovery of hindlimb motor function after SCI. Our work is a proof of principle demonstration that epidural electrical stimulation as a mode of inducing neuronal activity throughout white matter tracts of the CNS could be used to promote remyelination and functional recovery after CNS injuries and demyelination disorders.
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Affiliation(s)
- Qun Li
- 1 The International Center for Spinal Cord Injury, Hugo W. Moser Research Institute at Kennedy Krieger , Baltimore, Maryland
| | - Thierry Houdayer
- 1 The International Center for Spinal Cord Injury, Hugo W. Moser Research Institute at Kennedy Krieger , Baltimore, Maryland
| | - Su Liu
- 1 The International Center for Spinal Cord Injury, Hugo W. Moser Research Institute at Kennedy Krieger , Baltimore, Maryland
| | - Visar Belegu
- 1 The International Center for Spinal Cord Injury, Hugo W. Moser Research Institute at Kennedy Krieger , Baltimore, Maryland.,2 Department of Neurology, Johns Hopkins University School of Medicine , Baltimore, Maryland.,3 Department of Pathology, Johns Hopkins University School of Medicine , Baltimore, Maryland
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50
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Butensky SD, Sloan AP, Meyers E, Carmel JB. Dexterity: A MATLAB-based analysis software suite for processing and visualizing data from tasks that measure arm or forelimb function. J Neurosci Methods 2017; 286:114-124. [PMID: 28583476 DOI: 10.1016/j.jneumeth.2017.06.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 05/31/2017] [Accepted: 06/02/2017] [Indexed: 01/07/2023]
Abstract
BACKGROUND Hand function is critical for independence, and neurological injury often impairs dexterity. To measure hand function in people or forelimb function in animals, sensors are employed to quantify manipulation. These sensors make assessment easier and more quantitative and allow automation of these tasks. While automated tasks improve objectivity and throughput, they also produce large amounts of data that can be burdensome to analyze. We created software called Dexterity that simplifies data analysis of automated reaching tasks. NEW METHOD Dexterity is MATLAB software that enables quick analysis of data from forelimb tasks. Through a graphical user interface, files are loaded and data are identified and analyzed. These data can be annotated or graphed directly. Analysis is saved, and the graph and corresponding data can be exported. For additional analysis, Dexterity provides access to custom scripts created by other users. RESULTS To determine the utility of Dexterity, we performed a study to evaluate the effects of task difficulty on the degree of impairment after injury. Dexterity analyzed two months of data and allowed new users to annotate the experiment, visualize results, and save and export data easily. COMPARISON WITH EXISTING METHOD(S) Previous analysis of tasks was performed with custom data analysis, requiring expertise with analysis software. Dexterity made the tools required to analyze, visualize and annotate data easy to use by investigators without data science experience. CONCLUSIONS Dexterity increases accessibility to automated tasks that measure dexterity by making analysis of large data intuitive, robust, and efficient.
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Affiliation(s)
| | - Andrew P Sloan
- Texas Biomedical Center, The University of Texas at Dallas, Richardson, TX, 75080, USA; Erik Jonsson School of Engineering and Computer Science, The University of Texas at Dallas, Richardson, TX, 75080, USA.
| | - Eric Meyers
- Texas Biomedical Center, The University of Texas at Dallas, Richardson, TX, 75080, USA; Erik Jonsson School of Engineering and Computer Science, The University of Texas at Dallas, Richardson, TX, 75080, USA.
| | - Jason B Carmel
- Burke Medical Research Institute, White Plains, NY, 10605, USA; Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY, 10065, USA; Departments of Neurology and Pediatrics, Weill Cornell Medical College, New York, NY, USA.
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