1
|
Inoue T, Ueno M. The diversity and plasticity of descending motor pathways rewired after stroke and trauma in rodents. Front Neural Circuits 2025; 19:1566562. [PMID: 40191711 PMCID: PMC11968733 DOI: 10.3389/fncir.2025.1566562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2025] [Accepted: 03/10/2025] [Indexed: 04/09/2025] Open
Abstract
Descending neural pathways to the spinal cord plays vital roles in motor control. They are often damaged by brain injuries such as stroke and trauma, which lead to severe motor impairments. Due to the limited capacity for regeneration of neural circuits in the adult central nervous system, currently no essential treatments are available for complete recovery. Notably, accumulating evidence shows that residual circuits of the descending pathways are dynamically reorganized after injury and contribute to motor recovery. Furthermore, recent technological advances in cell-type classification and manipulation have highlighted the structural and functional diversity of these pathways. Here, we focus on three major descending pathways, namely, the corticospinal tract from the cerebral cortex, the rubrospinal tract from the red nucleus, and the reticulospinal tract from the reticular formation, and summarize the current knowledge of their structures and functions, especially in rodent models (mice and rats). We then review and discuss the process and patterns of reorganization induced in these pathways following injury, which compensate for lost connections for recovery. Understanding the basic structural and functional properties of each descending pathway and the principles of the induction and outcome of the rewired circuits will provide therapeutic insights to enhance interactive rewiring of the multiple descending pathways for motor recovery.
Collapse
Affiliation(s)
- Takahiro Inoue
- Department of System Pathology for Neurological Disorders, Brain Research Institute, Niigata University, Niigata, Japan
| | - Masaki Ueno
- Department of System Pathology for Neurological Disorders, Brain Research Institute, Niigata University, Niigata, Japan
| |
Collapse
|
2
|
Takatani H, Fujita N, Imai F, Yoshida Y. Modulation of Extrinsic and Intrinsic Signaling Together with Neuronal Activation Enhances Forelimb Motor Recovery after Cervical Spinal Cord Injury. eNeuro 2025; 12:ENEURO.0359-24.2025. [PMID: 39919817 PMCID: PMC11881905 DOI: 10.1523/eneuro.0359-24.2025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2024] [Revised: 02/03/2025] [Accepted: 02/03/2025] [Indexed: 02/09/2025] Open
Abstract
Singular strategies for promoting axon regeneration and motor recovery after spinal cord injury (SCI) have been attempted with limited success. For instance, the deletion of RhoA and phosphatase and tensin homolog (Pten) (an extrinsic and intrinsic modulating factor, respectively) in corticospinal neurons (CSNs) promotes axon sprouting after thoracic SCI; however, it is unable to restore motor function. Here, we examine the effects of combining RhoA/Pten deletion in CSNs with chemogenetic neuronal stimulation on axonal growth and motor recovery after SCI in mice. We find that this combinatorial approach promotes greater axonal growth and presynaptic bouton formation in CSNs within the spinal cord compared with RhoA;Pten deletion alone. Furthermore, chemogenetic neuronal stimulation of RhoA;Pten-deleted CSNs improves forelimb performance in behavioral tasks after SCI compared with RhoA;Pten deletion alone. These results demonstrate that combination therapies pairing genetic modifications with neuronal stimulation can promote greater presynaptic formation and motor recovery following SCI than either strategy alone.
Collapse
Affiliation(s)
- Hirohide Takatani
- Neural Connectivity Development in Physiology and Disease Laboratory, Burke Neurological Institute, White Plains, New York 10605
- Laboratory of Veterinary Surgery, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Naoki Fujita
- Laboratory of Veterinary Surgery, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Fumiyasu Imai
- Neural Connectivity Development in Physiology and Disease Laboratory, Burke Neurological Institute, White Plains, New York 10605
- Brain and Mind Research Institute, Weill Cornell Medicine, New York 10065
| | - Yutaka Yoshida
- Neural Connectivity Development in Physiology and Disease Laboratory, Burke Neurological Institute, White Plains, New York 10605
- Brain and Mind Research Institute, Weill Cornell Medicine, New York 10065
- Neural Circuit Unit, Okinawa Institute of Science and Technology Graduate University, Onna-son, Kunigami-gun, Okinawa 904-0495, Japan
| |
Collapse
|
3
|
Lv Y, Ji L, Dai H, Qiu S, Wang Y, Teng C, Yu B, Mi D, Yao C. Identification of key regulatory genes involved in myelination after spinal cord injury by GSEA analysis. Exp Neurol 2024; 382:114966. [PMID: 39326824 DOI: 10.1016/j.expneurol.2024.114966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Revised: 08/31/2024] [Accepted: 09/21/2024] [Indexed: 09/28/2024]
Abstract
Multilayer dense myelin tissue provides insulating space and nutritional support for axons in healthy spinal cord tissue. Oligodendrocyte precursor cells (OPCs) are the main glial cells that complement myelin loss in the central nervous system and play an important role in the repair of spinal cord injury (SCI). However, the regulation of axonal remyelination after SCI is still insufficient. In this study, we focused on the changes in genes related to myelin repair after rat hemisection SCI by gene set enrichment analysis (GSEA). Key genes proteolipid protein 1 (Plp1), hexosaminidase subunit alpha (Hexa), and hexosaminidase subunit beta (Hexb) during remyelination after SCI were found. Through quantitative real-time polymerase chain reaction (qPCR) experiments, we confirmed that within 28 days after rat hemisection SCI, the mRNA expression of gene Plp1 gradually decreased, while the expressions of gene Hexa and Hexb gradually increased, which was consistent with RNA sequencing results. In vitro, we performed EdU proliferation assays on OPC cell line OLN-93 and primary rat OPCs. We found that interference of Plp1 promoted OPC proliferation, while interference of Hexa and Hexb inhibited OPC proliferation. In addition, we performed in vitro differentiation experiments on primary rat OPCs. By measuring myelin sheath branch outgrowth and the fluorescence intensity of the mature myelin sheath marker myelin basic protein (MBP), we found that interference of Hexa or Hexb promoted OPC differentiation and maturation, but interference of Plp1 inhibited this process. Finally, we injected Hexb siRNA in vivo and found that interfering Hexb could improve motor movements and myelin regeneration after SCI in rats. Our results provide new target genes that can selectively regulate the proliferation and differentiation of endogenous OPCs, providing new ideas for promoting remyelination and functional recovery after SCI.
Collapse
Affiliation(s)
- Yehua Lv
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Affiliated Traditional Chinese Medicine Hospital and Medical School, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226001, Jiangsu, China
| | - Lingyun Ji
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Affiliated Traditional Chinese Medicine Hospital and Medical School, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226001, Jiangsu, China
| | - Hui Dai
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Affiliated Traditional Chinese Medicine Hospital and Medical School, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226001, Jiangsu, China
| | - Shanru Qiu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Affiliated Traditional Chinese Medicine Hospital and Medical School, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226001, Jiangsu, China
| | - Yu Wang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Affiliated Traditional Chinese Medicine Hospital and Medical School, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226001, Jiangsu, China
| | - Cheng Teng
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Affiliated Traditional Chinese Medicine Hospital and Medical School, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226001, Jiangsu, China
| | - Bin Yu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Affiliated Traditional Chinese Medicine Hospital and Medical School, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226001, Jiangsu, China
| | - Daguo Mi
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Affiliated Traditional Chinese Medicine Hospital and Medical School, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226001, Jiangsu, China.
| | - Chun Yao
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Affiliated Traditional Chinese Medicine Hospital and Medical School, Co-Innovation Center of Neuroregeneration, Nantong University, Nantong 226001, Jiangsu, China.
| |
Collapse
|
4
|
Wang Z, Brannigan M, Friedrich L, Blackmore MG. Chronic activation of corticospinal tract neurons after pyramidotomy injury enhances neither behavioral recovery nor axonal sprouting. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.10.25.620314. [PMID: 39484429 PMCID: PMC11527142 DOI: 10.1101/2024.10.25.620314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/03/2024]
Abstract
Modulation of neural activity is a promising strategy to influence the growth of axons and improve behavioral recovery after damage to the central nervous system. The benefits of neuromodulation likely depend on optimization across multiple input parameters. Here we used a chemogenetic approach to achieve continuous, long-term elevation of neural activity in murine corticospinal tract (CST) neurons. To specifically target CST neurons, AAV2-retro-DIO-hM3Dq-mCherry or matched mCherry control was injected to the cervical spinal cord of adult Emx1-Cre transgenic mice. Pilot studies verified efficient transgene expression in CST neurons and effective elevation of neural activity as assessed by cFos immunohistochemistry. In subsequent experiments mice were administered either DIO-hM3Dq-mCherry or control DIO-mCherry, were pre-trained on a pellet retrieval task, and then received unilateral pyramidotomy injury to selectively ablate the right CST. Mice then received continual clozapine via drinking water and weekly testing on the pellet retrieval task, followed by cortical injection of a viral tracer to assess cross-midline sprouting by the spared CST. After sacrifice at eight weeks post-injury immunohistochemistry for cFos verified elevated CST activity in hM3Dq-treated animals and immunohistochemistry for PKC-gamma verified unilateral ablation of the CST in all animals. Despite the chronic elevation of CST activity, however, both groups showed similar levels of cross-midline CST sprouting and similar success in the pellet retrieval task. These data indicate that continuous, long-term elevation of activity that is targeted specifically to CST neurons does not affect compensatory sprouting or directed forelimb movements.
Collapse
Affiliation(s)
- Zimei Wang
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI, 53201
| | - Matthew Brannigan
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI, 53201
| | - Logan Friedrich
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI, 53201
| | - Murray G. Blackmore
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI, 53201
| |
Collapse
|
5
|
Takatani H, Fujita N, Imai F, Yoshida Y. Forelimb motor recovery by modulating extrinsic and intrinsic signaling as well as neuronal activity after the cervical spinal cord injury. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.22.600167. [PMID: 38979293 PMCID: PMC11230274 DOI: 10.1101/2024.06.22.600167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Singular strategies for promoting axon regeneration and motor recovery after spinal cord injury (SCI) have been attempted with limited success. Here, we propose the combinatorial approach of deleting extrinsic and intrinsic factors paired with neural stimulation, will enhance adaptive axonal growth and motor recovery after SCI. We previously showed the deletion of RhoA and Pten in corticospinal neurons inhibits axon dieback and promotes axon sprouting after lumbar SCI. Here, we examined the effects of RhoA;Pten deletion coupled with neural stimulation after cervical SCI. This combinatorial approach promoted more boutons on injured corticospinal neurons in the spinal cord compared to sole RhoA;Pten deletion. Although RhoA;Pten deletion does not promote motor recovery in the forelimb after SCI, stimulating corticospinal neurons in those mice results in partial motor recovery. These results demonstrate that a combinatorial approach that pairs genetic modifications with neuronal stimulation can promote axon sprouting and motor recovery following SCI.
Collapse
Affiliation(s)
- Hirohide Takatani
- Burke Neurological Institute, White Plains, New York, United States
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, United States
- Laboratory of Veterinary Surgery, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Naoki Fujita
- Laboratory of Veterinary Surgery, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Fumiyasu Imai
- Burke Neurological Institute, White Plains, New York, United States
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, United States
| | - Yutaka Yoshida
- Burke Neurological Institute, White Plains, New York, United States
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, United States
- Neural Circuit Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
- Lead contact
| |
Collapse
|
6
|
Liu Z, Lai J, Kong D, Zhao Y, Zhao J, Dai J, Zhang M. Advances in electroactive bioscaffolds for repairing spinal cord injury. Biomed Mater 2024; 19:032005. [PMID: 38636508 DOI: 10.1088/1748-605x/ad4079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Accepted: 04/18/2024] [Indexed: 04/20/2024]
Abstract
Spinal cord injury (SCI) is a devastating neurological disorder, leading to loss of motor or somatosensory function, which is the most challenging worldwide medical problem. Re-establishment of intact neural circuits is the basis of spinal cord regeneration. Considering the crucial role of electrical signals in the nervous system, electroactive bioscaffolds have been widely developed for SCI repair. They can produce conductive pathways and a pro-regenerative microenvironment at the lesion site similar to that of the natural spinal cord, leading to neuronal regeneration and axonal growth, and functionally reactivating the damaged neural circuits. In this review, we first demonstrate the pathophysiological characteristics induced by SCI. Then, the crucial role of electrical signals in SCI repair is introduced. Based on a comprehensive analysis of these characteristics, recent advances in the electroactive bioscaffolds for SCI repair are summarized, focusing on both the conductive bioscaffolds and piezoelectric bioscaffolds, used independently or in combination with external electronic stimulation. Finally, thoughts on challenges and opportunities that may shape the future of bioscaffolds in SCI repair are concluded.
Collapse
Affiliation(s)
- Zeqi Liu
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, People's Republic of China
| | - Jiahui Lai
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, People's Republic of China
| | - Dexin Kong
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, People's Republic of China
| | - Yannan Zhao
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
| | - Jiakang Zhao
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, People's Republic of China
| | - Jianwu Dai
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, People's Republic of China
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
| | - Mingming Zhang
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, People's Republic of China
| |
Collapse
|
7
|
Dominguez-Bajo A, Clotman F. Potential Roles of Specific Subclasses of Premotor Interneurons in Spinal Cord Function Recovery after Traumatic Spinal Cord Injury in Adults. Cells 2024; 13:652. [PMID: 38667267 PMCID: PMC11048910 DOI: 10.3390/cells13080652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 04/04/2024] [Accepted: 04/05/2024] [Indexed: 04/28/2024] Open
Abstract
The differential expression of transcription factors during embryonic development has been selected as the main feature to define the specific subclasses of spinal interneurons. However, recent studies based on single-cell RNA sequencing and transcriptomic experiments suggest that this approach might not be appropriate in the adult spinal cord, where interneurons show overlapping expression profiles, especially in the ventral region. This constitutes a major challenge for the identification and direct targeting of specific populations that could be involved in locomotor recovery after a traumatic spinal cord injury in adults. Current experimental therapies, including electrical stimulation, training, pharmacological treatments, or cell implantation, that have resulted in improvements in locomotor behavior rely on the modulation of the activity and connectivity of interneurons located in the surroundings of the lesion core for the formation of detour circuits. However, very few publications clarify the specific identity of these cells. In this work, we review the studies where premotor interneurons were able to create new intraspinal circuits after different kinds of traumatic spinal cord injury, highlighting the difficulties encountered by researchers, to classify these populations.
Collapse
Affiliation(s)
- Ana Dominguez-Bajo
- Université catholique de Louvain, Louvain Institute of Biomolecular Science and Technology (LIBST), Animal Molecular and Cellular Biology Group (AMCB), Place Croix du Sud 4–5, 1348 Louvain la Neuve, Belgium
| | - Frédéric Clotman
- Université catholique de Louvain, Louvain Institute of Biomolecular Science and Technology (LIBST), Animal Molecular and Cellular Biology Group (AMCB), Place Croix du Sud 4–5, 1348 Louvain la Neuve, Belgium
| |
Collapse
|
8
|
Metcalfe M, Steward O. PTEN deletion in spinal pathways via retrograde transduction with AAV-RG enhances forelimb motor recovery after cervical spinal cord injury; Sex differences and late-onset pathophysiologies. Exp Neurol 2023; 370:114551. [PMID: 37778650 DOI: 10.1016/j.expneurol.2023.114551] [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: 07/24/2023] [Revised: 09/08/2023] [Accepted: 09/25/2023] [Indexed: 10/03/2023]
Abstract
Spinal cord injuries (SCI) cause permanent functional impairments due to interruption of motor and sensory pathways. Regeneration of axons does not occur due to lack of intrinsic growth capacity of adult neurons and extrinsic inhibitory factors, especially at the injury site. However, some regeneration can be achieved via deletion of the phosphatase and tensin homolog (PTEN) in cells of origin of spinal pathways. Here, we deployed an AAV variant that is retrogradely transported (AAV-rg) to deliver gene modifying cargos to the cells of origin of multiple pathways interrupted by SCI, testing whether this promoted recovery of motor function. PTENf/f;RosatdTomato mice and control RosatdTomato mice received injections of different doses (number of genome copies, GCs) of AAV-rg/Cre into the cervical spinal cord at the time of a C5 dorsal hemisection injury. Forelimb grip strength was tested over time using a grip strength meter. PTENf/f;RosatdTomato mice with AAV-rg/Cre (PTEN-deleted) exhibited substantial improvements in forelimb gripping ability in comparison to controls. Of note, there were major sex differences in the extent of recovery, with male mice exhibiting greater recovery than females. However, at around 5-7 weeks post-injury/injection, many mice with SCI and AAV-rg-mediated PTEN deletion began to exhibit pathophysiologies involving excessive scratching of the ears and back of the neck and rigid forward extension of the hindlimbs. These pathophysiologies increased in incidence and severity over time. Our results reveal that although intra-spinal injections of AAV-rg/Cre in PTENf/f;RosatdTomato mice can enhance forelimb motor recovery after SCI, late-developing functional abnormalities occur with the experimental conditions used here. Mechanisms underlying late-developing pathophysiologies remain to be defined.
Collapse
Affiliation(s)
- Mariajose Metcalfe
- Reeve-Irvine Research Center University of California Irvine School of Medicine, USA; Department of Anatomy & Neurobiology, University of California Irvine School of Medicine, USA
| | - 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.
| |
Collapse
|
9
|
Metcalfe M, Steward O. PTEN deletion in spinal pathways via retrograde transduction with AAV-rg enhances forelimb motor recovery after cervical spinal cord injury; sex differences and late-onset pathophysiologies. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.20.533502. [PMID: 36993317 PMCID: PMC10055283 DOI: 10.1101/2023.03.20.533502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
Spinal cord injuries (SCI) cause permanent functional impairments due to interruption of motor and sensory pathways. Regeneration of axons does not occur due to lack of intrinsic growth capacity of adult neurons and extrinsic inhibitory factors, especially at the injury site. However, some regeneration can be achieved via deletion of the phosphatase and tensin homolog (PTEN) in cells of origin of spinal pathways. Here, we deployed an AAV variant that is retrogradely transported (AAV-rg) to deliver gene modifying cargos to the cells of origin of multiple pathways interrupted by SCI, testing whether this promoted recovery of motor function. PTEN f/f ;Rosa tdTomato mice and control Rosa tdTomato mice received injections of different doses (number of genome copies, GCs) of AAV-rg/Cre into the cervical spinal cord at the time of a C5 dorsal hemisection injury. Forelimb grip strength was tested over time using a grip strength meter. PTEN f/f ;Rosa tdTomato mice with AAV-rg/Cre (PTEN-deleted) exhibited substantial improvements in forelimb gripping ability in comparison to controls. Of note, there were major sex differences in the extent of recovery, with male mice exhibiting greater recovery than females. However, at around 5-7 weeks post-injury/injection, many mice with SCI and AAV-rg-mediated PTEN deletion began to exhibit pathophysiologies involving excessive scratching of the ears and back of the neck and rigid forward extension of the hindlimbs. These pathophysiologies increased in incidence and severity over time. Our results reveal that although intra-spinal injections of AAV-rg/Cre in PTEN f/f ;Rosa tdTomato mice can enhance forelimb motor recovery after SCI, late-developing functional abnormalities occur with the experimental conditions used here. Mechanisms underlying late-developing pathophysiologies remain to be defined.
Collapse
|
10
|
Lai BQ, Wu RJ, Han WT, Bai YR, Liu JL, Yu HY, Yang SB, Wang LJ, Ren JL, Ding Y, Li G, Zeng X, Ma YH, Quan Q, Xing LY, Jiang B, Wang YQ, Zhang L, Chen ZH, Zhang HB, Chen YF, Zheng QJ, Zeng YS. Tail nerve electrical stimulation promoted the efficiency of transplanted spinal cord-like tissue as a neuronal relay to repair the motor function of rats with transected spinal cord injury. Biomaterials 2023; 297:122103. [PMID: 37028111 DOI: 10.1016/j.biomaterials.2023.122103] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 03/19/2023] [Accepted: 03/23/2023] [Indexed: 03/29/2023]
Abstract
Following transected spinal cord injury (SCI), there is a critical need to restore nerve conduction at the injury site and activate the silent neural circuits caudal to the injury to promote the recovery of voluntary movement. In this study, we generated a rat model of SCI, constructed neural stem cell (NSC)-derived spinal cord-like tissue (SCLT), and evaluated its ability to replace injured spinal cord and repair nerve conduction in the spinal cord as a neuronal relay. The lumbosacral spinal cord was further activated with tail nerve electrical stimulation (TNES) as a synergistic electrical stimulation to better receive the neural information transmitted by the SCLT. Next, we investigated the neuromodulatory mechanism underlying the action of TNES and its synergism with SCLT in SCI repair. TNES promoted the regeneration and remyelination of axons and increased the proportion of glutamatergic neurons in SCLT to transmit brain-derived neural information more efficiently to the caudal spinal cord. TNES also increased the innervation of motor neurons to hindlimb muscle and improved the microenvironment of muscle tissue, resulting in effective prevention of hindlimb muscle atrophy and enhanced muscle mitochondrial energy metabolism. Tracing of the neural circuits of the sciatic nerve and tail nerve identified the mechanisms responsible for the synergistic effects of SCLT transplantation and TNES in activating central pattern generator (CPG) neural circuits and promoting voluntary motor function recovery in rats. The combination of SCLT and TNES is expected to provide a new breakthrough for patients with SCI to restore voluntary movement and control their muscles.
Collapse
Affiliation(s)
- Bi-Qin Lai
- Key Laboratory for Stem Cells and Tissue Engineering, Sun Yat-sen University, Ministry of Education, Guangzhou, 510080, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, 226001, China; Department of Histology and Embryology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China; Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| | - Rong-Jie Wu
- Department of Orthopedics, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, 510100, China; Shantou University Medical College, Shantou, 515041, China
| | - Wei-Tao Han
- Co-innovation Center of Neuroregeneration, Nantong University, Nantong, 226001, China
| | - Yu-Rong Bai
- Key Laboratory for Stem Cells and Tissue Engineering, Sun Yat-sen University, Ministry of Education, Guangzhou, 510080, China
| | - Jia-Lin Liu
- Key Laboratory for Stem Cells and Tissue Engineering, Sun Yat-sen University, Ministry of Education, Guangzhou, 510080, China
| | - Hai-Yang Yu
- Department of Orthopedics, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, 510100, China
| | - Shang-Bin Yang
- Key Laboratory for Stem Cells and Tissue Engineering, Sun Yat-sen University, Ministry of Education, Guangzhou, 510080, China
| | - Lai-Jian Wang
- Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| | - Jia-Le Ren
- Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| | - Ying Ding
- Key Laboratory for Stem Cells and Tissue Engineering, Sun Yat-sen University, Ministry of Education, Guangzhou, 510080, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, 226001, China; Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| | - Ge Li
- Medical Research Center, Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Science, Guangzhou, 510100, China
| | - Xiang Zeng
- Key Laboratory for Stem Cells and Tissue Engineering, Sun Yat-sen University, Ministry of Education, Guangzhou, 510080, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, 226001, China; Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| | - Yuan-Huan Ma
- Guangzhou Institute of Clinical Medicine, Guangzhou First People's Hospital, South China University of Technology, Guangzhou, 510180, China
| | - Qi Quan
- Department of Orthopedic Surgery, Key Laboratory of Musculoskeletal Trauma & War Injuries PLA, Beijing Key Lab of Regenerative Medicine in Orthopedics, the 4th Medical Centre, Chinese PLA General Hospital, Beijing, 100048, China
| | - Ling-Yan Xing
- Department of Histology and Embryology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| | - Bin Jiang
- Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| | - Ya-Qiong Wang
- Department of Electron Microscope, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| | - Ling Zhang
- Department of Geriatrics, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, 510080, China
| | - Zheng-Hong Chen
- Department of Geriatrics, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, 510080, China
| | - Hong-Bo Zhang
- Co-innovation Center of Neuroregeneration, Nantong University, Nantong, 226001, China
| | - Yuan-Feng Chen
- Department of Orthopedics, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, 510100, China.
| | - Qiu-Jian Zheng
- Department of Orthopedics, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, 510100, China.
| | - Yuan-Shan Zeng
- Key Laboratory for Stem Cells and Tissue Engineering, Sun Yat-sen University, Ministry of Education, Guangzhou, 510080, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, 226001, China; Department of Histology and Embryology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China; Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China; Institute of Spinal Cord Injury, Sun Yat-sen University, Guangzhou, 510800, China.
| |
Collapse
|