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Enkavi G, Girych M, Moliner R, Vattulainen I, Castrén E. TrkB transmembrane domain: bridging structural understanding with therapeutic strategy. Trends Biochem Sci 2024; 49:445-456. [PMID: 38433044 DOI: 10.1016/j.tibs.2024.02.001] [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: 10/30/2023] [Revised: 01/19/2024] [Accepted: 02/09/2024] [Indexed: 03/05/2024]
Abstract
TrkB (neuronal receptor tyrosine kinase-2, NTRK2) is the receptor for brain-derived neurotrophic factor (BDNF) and is a critical regulator of activity-dependent neuronal plasticity. The past few years have witnessed an increasing understanding of the structure and function of TrkB, including its transmembrane domain (TMD). TrkB interacts with membrane cholesterol, which bidirectionally regulates TrkB signaling. Additionally, TrkB has recently been recognized as a binding target of antidepressant drugs. A variety of different antidepressants, including typical and rapid-acting antidepressants, as well as psychedelic compounds, act as allosteric potentiators of BDNF signaling through TrkB. This suggests that TrkB is the common target of different antidepressant compounds. Although more research is needed, current knowledge suggests that TrkB is a promising target for further drug development.
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Affiliation(s)
- Giray Enkavi
- Department of Physics, University of Helsinki, Helsinki, Finland
| | - Mykhailo Girych
- Department of Physics, University of Helsinki, Helsinki, Finland
| | - Rafael Moliner
- Neuroscience Center/HiLIFE, University of Helsinki, Helsinki, Finland
| | - Ilpo Vattulainen
- Department of Physics, University of Helsinki, Helsinki, Finland.
| | - Eero Castrén
- Neuroscience Center/HiLIFE, University of Helsinki, Helsinki, Finland.
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2
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Wang Y, Liang J, Xu B, Yang J, Wu Z, Cheng L. TrkB/BDNF signaling pathway and its small molecular agonists in CNS injury. Life Sci 2024; 336:122282. [PMID: 38008209 DOI: 10.1016/j.lfs.2023.122282] [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: 02/18/2023] [Revised: 10/19/2023] [Accepted: 11/18/2023] [Indexed: 11/28/2023]
Abstract
As one of the most prevalent neurotrophic factors in the central nervous system (CNS), brain-derived neurotrophic factor (BDNF) plays a significant role in CNS injury by binding to its specific receptor Tropomyosin-related kinase receptor B (TrkB). The BDNF/TrkB signaling pathway is crucial for neuronal survival, structural changes, and plasticity. BDNF acts as an axonal growth and extension factor, a pro-survival factor, and a synaptic modulator in the CNS. BDNF also plays an important role in the maintenance and plasticity of neuronal circuits. Several studies have demonstrated the importance of BDNF in the treatment and recovery of neurodegenerative and neurotraumatic disorders. By undertaking in-depth study on the mechanism of BDNF/TrkB function, important novel therapeutic strategies for treating neuropsychiatric disorders have been discovered. In this review, we discuss the expression patterns and mechanisms of the TrkB/BDNF signaling pathway in CNS damage and introduce several intriguing small molecule TrkB receptor agonists produced over the previous several decades.
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Affiliation(s)
- Yujin Wang
- Division of Spine, Department of Orthopedics, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, China; Key Laboratory of Spine and Spinal cord Injury Repair and Regeneration (Tongji University), Ministry of Education, Shanghai 200072, China; Medical School, Tongji University, Shanghai 200433, China
| | - Jing Liang
- Division of Spine, Department of Orthopedics, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, China; Key Laboratory of Spine and Spinal cord Injury Repair and Regeneration (Tongji University), Ministry of Education, Shanghai 200072, China; School of Stomatology, Tongji University, Shanghai 200072, China
| | - Boyu Xu
- Division of Spine, Department of Orthopedics, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, China; Key Laboratory of Spine and Spinal cord Injury Repair and Regeneration (Tongji University), Ministry of Education, Shanghai 200072, China; Medical School, Tongji University, Shanghai 200433, China
| | - Jin Yang
- Division of Spine, Department of Orthopedics, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, China; Key Laboratory of Spine and Spinal cord Injury Repair and Regeneration (Tongji University), Ministry of Education, Shanghai 200072, China; Medical School, Tongji University, Shanghai 200433, China
| | - Zhourui Wu
- Division of Spine, Department of Orthopedics, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, China; Key Laboratory of Spine and Spinal cord Injury Repair and Regeneration (Tongji University), Ministry of Education, Shanghai 200072, China.
| | - Liming Cheng
- Division of Spine, Department of Orthopedics, Tongji Hospital, Tongji University School of Medicine, Shanghai 200065, China; Key Laboratory of Spine and Spinal cord Injury Repair and Regeneration (Tongji University), Ministry of Education, Shanghai 200072, China.
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3
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Dejanovic B, Sheng M, Hanson JE. Targeting synapse function and loss for treatment of neurodegenerative diseases. Nat Rev Drug Discov 2024; 23:23-42. [PMID: 38012296 DOI: 10.1038/s41573-023-00823-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/06/2023] [Indexed: 11/29/2023]
Abstract
Synapse dysfunction and loss are hallmarks of neurodegenerative diseases that correlate with cognitive decline. However, the mechanisms and therapeutic strategies to prevent or reverse synaptic damage remain elusive. In this Review, we discuss recent advances in understanding the molecular and cellular pathways that impair synapses in neurodegenerative diseases, including the effects of protein aggregation and neuroinflammation. We also highlight emerging therapeutic approaches that aim to restore synaptic function and integrity, such as enhancing synaptic plasticity, preventing synaptotoxicity, modulating neuronal network activity and targeting immune signalling. We discuss the preclinical and clinical evidence for each strategy, as well as the challenges and opportunities for developing effective synapse-targeting therapeutics for neurodegenerative diseases.
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Affiliation(s)
| | - Morgan Sheng
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Jesse E Hanson
- Department of Neuroscience, Genentech, South San Francisco, CA, USA.
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4
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Liu S, Song L, Dai W, Liu M, Zhang H, Zhang X, Li H, Liu X, Lv Y, Hu Y. Worldwide productivity and research trend of publications concerning electroactive materials and spinal cord injury: A bibliometric study. Front Bioeng Biotechnol 2023; 11:1094059. [PMID: 36923456 PMCID: PMC10009169 DOI: 10.3389/fbioe.2023.1094059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 02/09/2023] [Indexed: 03/02/2023] Open
Abstract
Purpose: We investigated the current state and trends in the area during the previous 10 years using bibliometric approaches to evaluate the global scientific output of research on electroactive materials and spinal cord injury. Methods: Studies on spinal cord injury in electroactive materials that were published between 2012 and 2022 were located using the Web of science (WOS) datebase. The software programs bibliometrix R-package and CiteSpace were used to do quantitative analyses of annual publications, nation, author, institution, journal source, co-cited references, and keywords. The studies were categorized by the research's main points using a qualitative analysis, and publications having more than 10 citations each year. Results: In the final analysis, 1,330 relevant papers or reviews were included. There is an increased tendency in both the average annual citation rate and the number of publications in the discipline. The United States and the University of Toronto are the countries and institutions that have contributed the most to this discipline, respectively. The majority of authors are from the China and United States. Zhang Y is the author with the most published articles and holds the top position in the cited author h-index species. The journal with the highest number of published articles is "Disability and rehabilitation"; the journal is divided into four main areas including physics, materials, chemistry, molecular, and biology. The keyword analysis revealed a shift in research hotspots from schwann cell, fracture, and urinary disorders to carbon-based materials, functional recovery, and surgery. Analysis of qualitative data revealed that the role and mechanism of injectable conductive hydrogels in spinal cord healing after damage is a hot topic of current study, with the mechanism primarily focusing on the inhibition of oxidative stress (Nrf2) and apoptosis (Casepase 3). Conclusion: Our bibliometric analysis indicates that research on electroactive materials for spinal cord injury remains an active field of study. Moreover, contemporary research is concentrated on carbon-based materials, functional rehabilitation, and surgery.
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Affiliation(s)
- Sirui Liu
- Beijing Institute of Dental Research, Beijing Stomatological Hospital, Capital Medical University, Beijing, China
| | - Lin Song
- Beijing Institute of Dental Research, Beijing Stomatological Hospital, Capital Medical University, Beijing, China.,Department of Periodontology, Beijing Stomatological Hospital, Capital Medical University, Beijing, China
| | - Weishu Dai
- Beijing Institute of Dental Research, Beijing Stomatological Hospital, Capital Medical University, Beijing, China
| | - Mengdie Liu
- The Third Medical Center of PLA General Hospital, Beijing, China.,The First Medical Center of PLA General Hospital, Beijing, China
| | - Huijing Zhang
- Beijing Institute of Dental Research, Beijing Stomatological Hospital, Capital Medical University, Beijing, China.,Department of Periodontology, Beijing Stomatological Hospital, Capital Medical University, Beijing, China
| | - Xueyan Zhang
- Beijing Institute of Dental Research, Beijing Stomatological Hospital, Capital Medical University, Beijing, China
| | - Hongyu Li
- Beijing Institute of Dental Research, Beijing Stomatological Hospital, Capital Medical University, Beijing, China
| | - Xiu Liu
- Beijing Institute of Dental Research, Beijing Stomatological Hospital, Capital Medical University, Beijing, China
| | - Yan Lv
- Beijing Institute of Dental Research, Beijing Stomatological Hospital, Capital Medical University, Beijing, China
| | - Ying Hu
- Beijing Institute of Dental Research, Beijing Stomatological Hospital, Capital Medical University, Beijing, China
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5
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Mech D, Korgol K, Kurowska A, Adamski B, Miazga M, Biala G, Kruk-Slomka M. Promising Advances in Pharmacotherapy for Patients with Spinal Cord Injury-A Review of Studies Performed In Vivo with Modern Drugs. J Clin Med 2022; 11:jcm11226685. [PMID: 36431161 PMCID: PMC9698573 DOI: 10.3390/jcm11226685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 11/02/2022] [Accepted: 11/07/2022] [Indexed: 11/16/2022] Open
Abstract
Spinal cord injury (SCI) is a pathological neurological condition that leads to significant motor dysfunction. It is a condition that occurs as a result of tragic accidents, violent acts, or as a consequence of chronic diseases or degenerative changes. The current treatments for patients with SCI have moderate efficacy. They improve the quality of life of patients, but they are still doomed to long-term disability. In response to the modern directions of research on possible therapeutic methods that allow for the recovery of patients with SCI, a scientific review publication is needed to summarize the recent developments in this topic. The following review is focused on the available pharmacological treatments for SCIs and the problems that patients face depending on the location of the injury. In the following review, the research team describes problems related to spasticity and neuropathic pain; possible therapeutic pathways are also described for neuroprotection and the improvement of neurotransmission within the injured spinal cord, and the review focuses on issues related to oxidative stress.
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Affiliation(s)
- Dominika Mech
- Student Clubs and Organizations, Department of Pharmacology and Pharmacodynamics, Medical University of Lublin, Chodzki 4a Street, 20-093 Lublin, Poland
| | - Katarzyna Korgol
- Student Clubs and Organizations, Department of Pharmacognosy and Pharmaceutical Botany, Medical University of Lublin, Chodzki 1 Street, 20-400 Lublin, Poland
| | - Antonina Kurowska
- Student Clubs and Organizations, Department of Pharmacology and Pharmacodynamics, Medical University of Lublin, Chodzki 4a Street, 20-093 Lublin, Poland
| | - Bartlomiej Adamski
- Student Clubs and Organizations, Department of Pharmacology and Pharmacodynamics, Medical University of Lublin, Chodzki 4a Street, 20-093 Lublin, Poland
| | - Malgorzata Miazga
- Student Clubs and Organizations, Department of Pharmacognosy and Pharmaceutical Botany, Medical University of Lublin, Chodzki 1 Street, 20-400 Lublin, Poland
| | - Grazyna Biala
- Department of Pharmacology and Pharmacodynamics, Medical University of Lublin, Chodzki 4a Street, 20-093 Lublin, Poland
| | - Marta Kruk-Slomka
- Department of Pharmacology and Pharmacodynamics, Medical University of Lublin, Chodzki 4a Street, 20-093 Lublin, Poland
- Correspondence: ; Tel.: +48-8-1448-7258; Fax: +48-8-1448-7252
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6
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Clarke E, Stocki P, Sinclair EH, Gauhar A, Fletcher EJR, Krawczun-Rygmaczewska A, Duty S, Walsh FS, Doherty P, Rutkowski JL. A Single Domain Shark Antibody Targeting the Transferrin Receptor 1 Delivers a TrkB Agonist Antibody to the Brain and Provides Full Neuroprotection in a Mouse Model of Parkinson’s Disease. Pharmaceutics 2022; 14:pharmaceutics14071335. [PMID: 35890231 PMCID: PMC9318160 DOI: 10.3390/pharmaceutics14071335] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/20/2022] [Accepted: 06/22/2022] [Indexed: 02/04/2023] Open
Abstract
Single domain shark antibodies that bind to the transferrin receptor 1 (TfR1) on brain endothelial cells have been used to shuttle antibodies and other cargos across the blood brain barrier (BBB) to the brain. For these studies the TXB4 brain shuttle was fused to a TrkB neurotrophin receptor agonist antibody. The TXB4-TrkB fusion retained potent agonist activity at its cognate receptor and after systemic administration showed a 12-fold increase in brain levels over the unmodified antibody. Only the TXB4-TrkB antibody fusion was detected within the brain and localized to TrkB positive cells in the cortex and tyrosine hydroxylase (TH) positive dopaminergic neurons in the substantia nigra pars compacta (SNc), where it was associated with activated ERK1/2 signaling. When tested in the 6-hydroxydopamine (6-OHDA) mouse model of Parkinson’s disease (PD), TXB4-TrkB, but not the unmodified antibody, completely prevented the 6-OHDA induced death of TH positive neurons in the SNc. In conclusion, the fusion of the TXB4 brain shuttle allows a TrkB agonist antibody to reach neuroprotective concentrations in the brain parenchyma following systemic administration.
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Affiliation(s)
- Emily Clarke
- King’s College London, Institute of Psychiatry, Psychology and Neuroscience, Wolfson Centre for Age-Related Disease, Guy’s Campus, London SE1 1UL, UK; (E.C.); (E.J.R.F.); (A.K.-R.); (S.D.); (P.D.)
| | - Pawel Stocki
- Ossianix, Inc., Gunnels Wood Rd., Stevenage SG1 2FX, UK; (P.S.); (E.H.S.); (A.G.); (F.S.W.)
| | - Elizabeth H. Sinclair
- Ossianix, Inc., Gunnels Wood Rd., Stevenage SG1 2FX, UK; (P.S.); (E.H.S.); (A.G.); (F.S.W.)
| | - Aziz Gauhar
- Ossianix, Inc., Gunnels Wood Rd., Stevenage SG1 2FX, UK; (P.S.); (E.H.S.); (A.G.); (F.S.W.)
| | - Edward J. R. Fletcher
- King’s College London, Institute of Psychiatry, Psychology and Neuroscience, Wolfson Centre for Age-Related Disease, Guy’s Campus, London SE1 1UL, UK; (E.C.); (E.J.R.F.); (A.K.-R.); (S.D.); (P.D.)
| | - Alicja Krawczun-Rygmaczewska
- King’s College London, Institute of Psychiatry, Psychology and Neuroscience, Wolfson Centre for Age-Related Disease, Guy’s Campus, London SE1 1UL, UK; (E.C.); (E.J.R.F.); (A.K.-R.); (S.D.); (P.D.)
| | - Susan Duty
- King’s College London, Institute of Psychiatry, Psychology and Neuroscience, Wolfson Centre for Age-Related Disease, Guy’s Campus, London SE1 1UL, UK; (E.C.); (E.J.R.F.); (A.K.-R.); (S.D.); (P.D.)
| | - Frank S. Walsh
- Ossianix, Inc., Gunnels Wood Rd., Stevenage SG1 2FX, UK; (P.S.); (E.H.S.); (A.G.); (F.S.W.)
| | - Patrick Doherty
- King’s College London, Institute of Psychiatry, Psychology and Neuroscience, Wolfson Centre for Age-Related Disease, Guy’s Campus, London SE1 1UL, UK; (E.C.); (E.J.R.F.); (A.K.-R.); (S.D.); (P.D.)
| | - Julia Lynn Rutkowski
- Ossianix, Inc., Gunnels Wood Rd., Stevenage SG1 2FX, UK; (P.S.); (E.H.S.); (A.G.); (F.S.W.)
- Correspondence: ; Tel.: +1-(610)-291-1724
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7
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Liu XY, Chen C, Xu HH, Zhang YS, Zhong L, Hu N, Jia XL, Wang YW, Zhong KH, Liu C, Zhu X, Ming D, Li XH. Integrated printed BDNF/collagen/chitosan scaffolds with low temperature extrusion 3D printer accelerated neural regeneration after spinal cord injury. Regen Biomater 2021; 8:rbab047. [PMID: 34513004 PMCID: PMC8417565 DOI: 10.1093/rb/rbab047] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 07/19/2021] [Accepted: 08/01/2021] [Indexed: 02/06/2023] Open
Abstract
Recent studies have shown that 3D printed scaffolds integrated with growth factors can guide the growth of neurites and promote axon regeneration at the injury site. However, heat, organic solvents or cross-linking agents used in conventional 3D printing reduce the biological activity of growth factors. Low temperature 3D printing can incorporate growth factors into the scaffold and maintain their biological activity. In this study, we developed a collagen/chitosan scaffold integrated with brain-derived neurotrophic factor (3D-CC-BDNF) by low temperature extrusion 3D printing as a new type of artificial controlled release system, which could prolong the release of BDNF for the treatment of spinal cord injury (SCI). Eight weeks after the implantation of scaffolds in the transected lesion of T10 of the spinal cord, 3D-CC-BDNF significantly ameliorate locomotor function of the rats. Consistent with the recovery of locomotor function, 3D-CC-BDNF treatment could fill the gap, facilitate nerve fiber regeneration, accelerate the establishment of synaptic connections and enhance remyelination at the injury site.
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Affiliation(s)
- Xiao-Yin Liu
- Tianjin Key Laboratory of Brain Science and Neural Engineering, Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin 300072, China.,Tianjin Key Laboratory of Neurotrauma Repair, Pingjin Hospital Brain Center, Characteristic Medical Center of PAPF, Tianjin 300162, China.,National Engineering Research Center in Biomaterials, College of Biomedical Engineering, Sichuan University, Chengdu 610064, Sichuan, China.,Department of Neurosurgery, West China Medical School, West China Hospital, Sichuan University, Chengdu 610041, Sichuan, China
| | - Chong Chen
- Tianjin Key Laboratory of Brain Science and Neural Engineering, Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin 300072, China.,Tianjin Key Laboratory of Neurotrauma Repair, Pingjin Hospital Brain Center, Characteristic Medical Center of PAPF, Tianjin 300162, China
| | - Hai-Huan Xu
- Tianjin Key Laboratory of Brain Science and Neural Engineering, Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin 300072, China.,Tianjin Key Laboratory of Neurotrauma Repair, Pingjin Hospital Brain Center, Characteristic Medical Center of PAPF, Tianjin 300162, China
| | - Yu-Sheng Zhang
- National Engineering Research Center in Biomaterials, College of Biomedical Engineering, Sichuan University, Chengdu 610064, Sichuan, China
| | - Lin Zhong
- Department of Hematology, The First Affiliated Hospital of Chengdu Medical College, Chengdu 610500, Sichuan, China
| | - Nan Hu
- Tianjin Key Laboratory of Brain Science and Neural Engineering, Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin 300072, China
| | - Xiao-Li Jia
- Tianjin Key Laboratory of Brain Science and Neural Engineering, Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin 300072, China
| | - You-Wei Wang
- Tianjin Key Laboratory of Brain Science and Neural Engineering, Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin 300072, China
| | - Kun-Hong Zhong
- Department of Neurosurgery, West China Medical School, West China Hospital, Sichuan University, Chengdu 610041, Sichuan, China
| | - Chang Liu
- Department of Neurosurgery, West China Medical School, West China Hospital, Sichuan University, Chengdu 610041, Sichuan, China
| | - Xu Zhu
- Tianjin Key Laboratory of Neurotrauma Repair, Pingjin Hospital Brain Center, Characteristic Medical Center of PAPF, Tianjin 300162, China
| | - Dong Ming
- Tianjin Key Laboratory of Brain Science and Neural Engineering, Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin 300072, China
| | - Xiao-Hong Li
- Tianjin Key Laboratory of Brain Science and Neural Engineering, Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin 300072, China
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8
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Kramer AA, Olson GM, Chakraborty A, Blackmore MG. Promotion of corticospinal tract growth by KLF6 requires an injury stimulus and occurs within four weeks of treatment. Exp Neurol 2021; 339:113644. [PMID: 33592210 DOI: 10.1016/j.expneurol.2021.113644] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 01/23/2021] [Accepted: 02/12/2021] [Indexed: 12/01/2022]
Abstract
Axons in the corticospinal tract (CST) display a limited capacity for compensatory sprouting after partial spinal injuries, potentially limiting functional recovery. Forced expression of a developmentally expressed transcription factor, Krüppel-like factor 6 (KLF6), enhances axon sprouting by adult CST neurons. Here, using a pyramidotomy model of injury in adult mice, we confirm KLF6's pro-sprouting properties in spared corticospinal tract neurons and show that this effect depends on an injury stimulus. In addition, we probed the time course of KLF6-triggered sprouting of CST axons and demonstrate a significant enhancement of growth within four weeks of treatment. Finally, we tested whether KLF6-induced sprouting was accompanied by improvements in forelimb function, either singly or when combined with intensive rehabilitation. We found that regardless of rehabilitative training, and despite robust cross-midline sprouting by corticospinal tract axons, treatment with KLF6 produced no significant improvement in forelimb function on either a modified ladder-crossing task or a pellet-retrieval task. These data clarify important details of KLF6's pro-growth properties and indicate that additional interventions or further optimization will be needed to translate this improvement in axon growth into functional gains.
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Affiliation(s)
- Audra A Kramer
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI 53233, USA.
| | - Greta M Olson
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI 53233, USA.
| | - Advaita Chakraborty
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI 53233, USA.
| | - Murray G Blackmore
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI 53233, USA.
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9
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Jing Y, Bai F, Chen H, Dong H. Melatonin prevents blood vessel loss and neurological impairment induced by spinal cord injury in rats. J Spinal Cord Med 2017; 40:222-229. [PMID: 27735218 PMCID: PMC5430480 DOI: 10.1080/10790268.2016.1227912] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
BACKGROUND Melatonin can be neuroprotective in models of neurological injury, but its effects on blood vessel loss and neurological impairment following spinal cord injury (SCI) are unclear. Our goal herein was to evaluate the possible protective action of melatonin on the above SCI-induced damage in rats. MATERIALS AND METHODS Sixty-three female Sprague-Dawley rats were randomly divided into three equal groups: sham, SCI and melatonin groups. Melatonin (10 mg/kg) was injected intraperitoneally and further administered twice a day at indicated time after a moderate injury at T10 in melatonin group. Blood vessel was assessed by CD31staining and FITC-LEA, the permeability of blood-spinal cord barrier (BSCB) was detected by Evan's Blue. Neuron was assessed by NeuN staining and the expression of Nissl bodies in the neurons was assessed by Nissl staining. The expressions of brain-derived neurotrophic factor (BDNF), synapsin I, or growth associated protein-43 (GAP-43) in the spinal cord and hippocampus were evaluated by Western blotting. RESULTS At 7 days post-injury, melatonin treatment rescued blood vessels, increased CD31 levels, ameliorated BSCB permeability. Additionally, melatonin significantly increased the number of neurons and the expression of Nissl bodies in neurons at the injury epicenter. Furthermore, our data showed that SCI reduced levels of the molecular substrates of neurological plasticity, including BDNF, synapsin I, or GAP-43 in the spinal cord and hippocampus. Melatonin treatment partially prevented these reductions. CONCLUSION The neuroprotective effect of melatonin was associated with melioration of the microcirculation in the spinal cord and reduction of neurological impairment in the spinal cord and brain.
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Affiliation(s)
- Yingli Jing
- China Rehabilitation Research Center, Beijing, China,Institute of Rehabilitation Science of China, Beijing, China,Center of Neural Injury and Repair, Beijing Institute for Brain Disorders, Beijing, China,Beijing Key Laboratory of Neural Injury and Rehabilitation, Beijing, China
| | - Fan Bai
- China Rehabilitation Research Center, Beijing, China,Institute of Rehabilitation Science of China, Beijing, China,Center of Neural Injury and Repair, Beijing Institute for Brain Disorders, Beijing, China,Beijing Key Laboratory of Neural Injury and Rehabilitation, Beijing, China
| | - Hui Chen
- China Rehabilitation Research Center, Beijing, China,Institute of Rehabilitation Science of China, Beijing, China,Center of Neural Injury and Repair, Beijing Institute for Brain Disorders, Beijing, China,Beijing Key Laboratory of Neural Injury and Rehabilitation, Beijing, China
| | - Hao Dong
- China Rehabilitation Research Center, Beijing, China,Institute of Rehabilitation Science of China, Beijing, China,Center of Neural Injury and Repair, Beijing Institute for Brain Disorders, Beijing, China,Beijing Key Laboratory of Neural Injury and Rehabilitation, Beijing, China,Correspondence to: Hao Dong, Number 10, Jiao men North Road, Feng tai District, Beijing 100068, China.
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10
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Huang L, Xian Q, Shen N, Shi L, Qu Y, Zhou L. Congenital absence of corticospinal tract does not severely affect plastic changes of the developing postnatal spinal cord. Neuroscience 2015; 301:338-50. [DOI: 10.1016/j.neuroscience.2015.06.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2015] [Revised: 06/06/2015] [Accepted: 06/08/2015] [Indexed: 11/25/2022]
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11
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Collyer E, Catenaccio A, Lemaitre D, Diaz P, Valenzuela V, Bronfman F, Court FA. Sprouting of axonal collaterals after spinal cord injury is prevented by delayed axonal degeneration. Exp Neurol 2014; 261:451-61. [PMID: 25079366 DOI: 10.1016/j.expneurol.2014.07.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 07/02/2014] [Accepted: 07/20/2014] [Indexed: 01/24/2023]
Abstract
After an incomplete spinal cord injury (SCI), partial recovery of locomotion is accomplished with time. Previous studies have established a functional link between extension of axon collaterals from spared spinal tracts and locomotor recovery after SCI, but the tissular signals triggering collateral sprouting have not been identified. Here, we investigated whether axonal degeneration after SCI contributes to the sprouting of collaterals from axons spared after injury. To this end, we evaluated collateral sprouting from BDA-labeled uninjured corticospinal axons after spinal cord hemisection (SCI(H)) in wild type (WT) mouse and Wld(S) mouse strains, which shows a significant delay in Wallerian degeneration after injury. After SCI(H), spared fibers of WT mice extend collateral sprouts to both intact and denervated sides of the spinal cord distant from the injury site. On the contrary, in the Wld(S) mice collateral sprouting from spared fibers was greatly reduced after SCI(H). Consistent with a role for collateral sprouting in functional recovery after SCI, locomotor recovery after SCI(H) was impaired in Wld(S) mice compared to WT animals. In conclusion, our results identify axonal degeneration as one of the triggers for collateral sprouting from the contralesional uninjured fibers after an SCI(H). These results open the path for identifying molecular signals associated with tissular changes after SCI that promotes collateral sprouting and functional recovery.
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Affiliation(s)
- E Collyer
- Millenium Nucleus for Regenerative Biology, Faculty of Biology, Pontificia Universidad Catolica de Chile, Santiago, Chile.
| | - A Catenaccio
- Millenium Nucleus for Regenerative Biology, Faculty of Biology, Pontificia Universidad Catolica de Chile, Santiago, Chile.
| | - D Lemaitre
- Millenium Nucleus for Regenerative Biology, Faculty of Biology, Pontificia Universidad Catolica de Chile, Santiago, Chile.
| | - P Diaz
- Millenium Nucleus for Regenerative Biology, Faculty of Biology, Pontificia Universidad Catolica de Chile, Santiago, Chile.
| | - V Valenzuela
- Millenium Nucleus for Regenerative Biology, Faculty of Biology, Pontificia Universidad Catolica de Chile, Santiago, Chile.
| | - F Bronfman
- Millenium Nucleus for Regenerative Biology, Faculty of Biology, Pontificia Universidad Catolica de Chile, Santiago, Chile.
| | - F A Court
- Millenium Nucleus for Regenerative Biology, Faculty of Biology, Pontificia Universidad Catolica de Chile, Santiago, Chile; Neurounion Biomedical Foundation, Santiago, Chile.
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Kim GS, Cho S, Nelson JW, Zipfel GJ, Han BH. TrkB agonist antibody pretreatment enhances neuronal survival and long-term sensory motor function following hypoxic ischemic injury in neonatal rats. PLoS One 2014; 9:e88962. [PMID: 24551199 PMCID: PMC3925177 DOI: 10.1371/journal.pone.0088962] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 01/16/2014] [Indexed: 12/13/2022] Open
Abstract
Perinatal hypoxic ischemia (H-I) causes brain damage and long-term neurological impairments, leading to motor dysfunctions and cerebral palsy. Many studies have demonstrated that the TrkB-ERK1/2 signaling pathway plays a key role in mediating the protective effect of brain-derived neurotrophic factor (BDNF) following perinatal H-I brain injury in experimental animals. In the present study, we explored the neuroprotective effects of the TrkB-specific agonist monoclonal antibody 29D7 on H-I brain injury in neonatal rats. First, we found that intracerebroventricular (icv) administration of 29D7 in normal P7 rats markedly increased the levels of phosphorylated ERK1/2 and phosphorylated AKT in neurons up to 24 h. Second, P7 rats received icv administration of 29D7 and subjected to H-I injury induced by unilateral carotid artery ligation and exposure to hypoxia (8% oxygen). We found that 29D7, to a similar extent to BDNF, significantly inhibited activation of caspase-3, a biochemical hallmark of apoptosis, following H-I injury. Third, we found that this 29D7-mediated neuroprotective action persisted at least up to 5 weeks post-H-I injury as assessed by brain tissue loss, implicating long-term neurotrophic effects rather than an acute delay of cell death. Moreover, the long-term neuroprotective effect of 29D7 was tightly correlated with sensorimotor functional recovery as assessed by a tape-removal test, while 29D7 did not significantly improve rotarod performance. Taken together, these findings demonstrate that pretreatment with the TrkB-selective agonist 29D7 significantly increases neuronal survival and behavioral recovery following neonatal hypoxic-ischemic brain injury.
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Affiliation(s)
- Gab Seok Kim
- Department of Pharmacology, Seoul National University, College of Pharmacy, Seoul, Republic of Korea
| | - Seongeun Cho
- Wyeth Neuroscience Discovery Research, Princeton, New Jersey, United States of America
| | - James W. Nelson
- Department of Neurological Surgery Washington University School of Medicine, St. Louis, Missouri, United States of America
- Hope Center for Neurological Disorders Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Gregory J. Zipfel
- Department of Neurological Surgery Washington University School of Medicine, St. Louis, Missouri, United States of America
- Hope Center for Neurological Disorders Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Byung Hee Han
- Department of Pharmacology, Seoul National University, College of Pharmacy, Seoul, Republic of Korea
- Department of Neurological Surgery Washington University School of Medicine, St. Louis, Missouri, United States of America
- Hope Center for Neurological Disorders Washington University School of Medicine, St. Louis, Missouri, United States of America
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Fouad K, Bennett DJ, Vavrek R, Blesch A. Long-term viral brain-derived neurotrophic factor delivery promotes spasticity in rats with a cervical spinal cord hemisection. Front Neurol 2013; 4:187. [PMID: 24312075 PMCID: PMC3832889 DOI: 10.3389/fneur.2013.00187] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Accepted: 11/04/2013] [Indexed: 12/31/2022] Open
Abstract
We have recently reported that rats with complete thoracic spinal cord injury (SCI) that received a combinatorial treatment, including viral brain-derived neurotrophic factor (BDNF) delivery in the spinal cord, not only showed enhanced axonal regeneration, but also deterioration of hind-limb motor function. By demonstrating that BDNF over-expression can trigger spasticity-like symptoms in a rat model of sacral SCI, we proposed a causal relationship between the observed spasticity-like symptoms (i.e., resistance to passive range of motion) and the over-expression of BDNF. The current study was originally designed to evaluate a comparable combined treatment for cervical SCI in the rat to improve motor recovery. Once again we found similar signs of spasticity involving clenching of the paws and wrist flexion. This finding changed the focus of the study and, we then explored whether this spasticity-like symptom is directly related to the over-expression of BDNF by administering a BDNF antagonist. Using electromyographic measurements we showed that this treatment gradually diminished the resistance to overcome forelimb flexion in an acute experiment. Thus, we conclude that neuro-excitatory effects of chronic BDNF delivery together with diminished descending control after SCI can result in adverse effects.
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Affiliation(s)
- Karim Fouad
- Rehabilitation Medicine, University of Alberta , Edmonton, AB , Canada
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Weishaupt N, Krajacic A, Fouad K. Lipopolysaccharide can induce errors in anatomical measures of neuronal plasticity by increasing tracing efficacy. Neurosci Lett 2013; 556:181-5. [PMID: 24157856 DOI: 10.1016/j.neulet.2013.10.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Revised: 10/09/2013] [Accepted: 10/11/2013] [Indexed: 01/10/2023]
Abstract
Evidence suggests that activating certain components of the immune system may increase regeneration and plasticity in the injured central nervous system. Investigating the effect of lipopolysaccharide (LPS), a potent endotoxin and immune activator, on neuronal plasticity in rat models of spinal cord injury, we discovered that systemic administration of LPS can increase the number of descending motor axons that transport neuronal tracers anterogradely to the spinal cord. This effect of LPS was not observed across all motor tracts traced in two different experiments, but was significant for two different tracers administered to corticospinal tract neurons. Densitometry measurement of traced corticospinal axons within the cervical gray matter revealed that normalization to the number of traced axons is crucial to avoid false-positive reports of increased plasticity following LPS injection. These findings indicate that assessments of neuronal growth based on neuronal tracing techniques should be normalized when inflammation or immune activation is an experimental variable.
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Affiliation(s)
- Nina Weishaupt
- Centre for Neuroscience, University of Alberta, 3-88 Corbett Hall, Edmonton, AB T6E 2G4, Canada.
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Weishaupt N, Vavrek R, Fouad K. Training following unilateral cervical spinal cord injury in rats affects the contralesional forelimb. Neurosci Lett 2013; 539:77-81. [DOI: 10.1016/j.neulet.2013.01.043] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Revised: 01/02/2013] [Accepted: 01/19/2013] [Indexed: 10/27/2022]
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Weishaupt N, Li S, Di Pardo A, Sipione S, Fouad K. Synergistic effects of BDNF and rehabilitative training on recovery after cervical spinal cord injury. Behav Brain Res 2012; 239:31-42. [PMID: 23131414 DOI: 10.1016/j.bbr.2012.10.047] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Revised: 10/23/2012] [Accepted: 10/28/2012] [Indexed: 12/25/2022]
Abstract
Promoting the rewiring of lesioned motor tracts following a spinal cord injury is a promising strategy to restore motor function. For instance, axonal collaterals may connect to spared, lesion-bridging neurons, thereby establishing a detour for descending signals and thus promoting functional recovery. In our rat model of cervical spinal cord injury, we attempted to promote targeted rewiring of the unilaterally injured corticospinal tract (CST) via the spared reticulospinal tract (RtST). To promote new connections between the two tracts in the brainstem, we administered viral vectors producing two neurotrophins. Brain-derived neurotrophic factor (BDNF), a known promotor of collateral growth, was expressed in the motor cortex, and neurotrophin 3 (NT-3), which has chemoattractive properties, was expressed in the reticular formation. Because rehabilitative training has proven to be beneficial in promoting functionally meaningful plasticity following injury, we added training in a skilled reaching task. Different neurotrophin or control treatments with or without training were evaluated. As hypothesized, improvements of motor performance with the injured forelimb following neurotrophin treatment alone were absent or modest compared to untreated controls. In contrast, we found a significant synergistic effect on performance when BDNF treatment was combined with training. The mechanism of this recovery remains unidentified, as histological analyses of CST and RtST collateral projections did not reveal differences among treatment groups. In conclusion, we demonstrate that following a cervical spinal lesion, rehabilitative training is necessary to translate effects of BDNF into functional recovery by mechanisms which are likely independent of collateral sprouting of the CST or RtST into the gray matter.
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Affiliation(s)
- N Weishaupt
- Centre for Neuroscience, University of Alberta, Edmonton, AB, Canada.
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Onifer SM, Smith GM, Fouad K. Plasticity after spinal cord injury: relevance to recovery and approaches to facilitate it. Neurotherapeutics 2011; 8:283-93. [PMID: 21384221 PMCID: PMC3101826 DOI: 10.1007/s13311-011-0034-4] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Motor, sensory, and autonomic functions can spontaneously return or recover to varying extents in both humans and animals, regardless of the traumatic spinal cord injury (SCI) level and whether it was complete or incomplete. In parallel, adverse and painful functions can appear. The underlying mechanisms for all of these diverse functional changes are summarized under the term plasticity. Our review will describe what is known regarding this phenomenon after traumatic SCI and focus on its relevance to motor and sensory recovery. Although it is still somewhat speculative, plasticity can be found throughout the neuraxis and includes various changes ranging from alterations in the properties of spared neuronal circuitries, intact or lesioned axon collateral sprouting, and synaptic rearrangements. Furthermore, we will discuss a selection of potential approaches for facilitating plasticity as possible SCI treatments. Because a mechanism underlying spontaneous plasticity and recovery might be motor activity and the related neuronal activity, activity-based therapies are being used and investigated both clinically and experimentally. Additional pharmacological and gene-delivery approaches, based on plasticity being dependent on the delicate balance between growth inhibition and promotion as well as the basic intrinsic growth ability of the neurons themselves, have been found to be effective alone and in combination with activity-based therapies. The positive results have to be tempered with the reality that not all plasticity is beneficial. Therefore, a tremendous number of questions still need to be addressed. Ultimately, answers to these questions will enhance plasticity's potential for improving the quality of life for persons with SCI.
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Affiliation(s)
- Stephen M. Onifer
- Spinal Cord and Brain Injury Research Center, University of Kentucky, College of Medicine, Lexington, Kentucky 40536-0509 USA
- Department of Anatomy and Neurobiology, University of Kentucky, College of Medicine, Lexington, Kentucky 40536-0098 USA
| | - George M. Smith
- Spinal Cord and Brain Injury Research Center, University of Kentucky, College of Medicine, Lexington, Kentucky 40536-0509 USA
- Department of Physiology, University of Kentucky, College of Medicine, Lexington, Kentucky 40536-0298 USA
| | - Karim Fouad
- Rehabilitation Medicine, University of Alberta, Edmonton, Alberta, T6G 2G4 Canada
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