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Yu Z, Ding R, Yan Q, Cheng M, Li T, Zheng F, Zhu L, Wang Y, Tang T, Hu E. A Novel Network Pharmacology Strategy Based on the Universal Effectiveness-Common Mechanism of Medical Herbs Uncovers Therapeutic Targets in Traumatic Brain Injury. Drug Des Devel Ther 2024; 18:1175-1188. [PMID: 38645986 PMCID: PMC11032138 DOI: 10.2147/dddt.s450895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 04/10/2024] [Indexed: 04/23/2024] Open
Abstract
Purpose Many herbs can promote neurological recovery following traumatic brain injury (TBI). There must lie a shared mechanism behind the common effectiveness. We aimed to explore the key therapeutic targets for TBI based on the common effectiveness of the medicinal plants. Material and methods The TBI-effective herbs were retrieved from the literature as imputes of network pharmacology. Then, the active ingredients in at least two herbs were screened out as common components. The hub targets of all active compounds were identified through Cytohubba. Next, AutoDock vina was used to rank the common compound-hub target interactions by molecular docking. A highly scored compound-target pair was selected for in vivo validation. Results We enrolled sixteen TBI-effective medicinal herbs and screened out twenty-one common compounds, such as luteolin. Ten hub targets were recognized according to the topology of the protein-protein interaction network of targets, including epidermal growth factor receptor (EGFR). Molecular docking analysis suggested that luteolin could bind strongly to the active pocket of EGFR. Administration of luteolin or the selective EGFR inhibitor AZD3759 to TBI mice promoted the recovery of body weight and neurological function, reduced astrocyte activation and EGFR expression, decreased chondroitin sulfate proteoglycans deposition, and upregulated GAP43 levels in the cortex. The effects were similar to those when treated with the selective EGFR inhibitor. Conclusion The common effectiveness-based, common target screening strategy suggests that inhibition of EGFR can be an effective therapy for TBI. This strategy can be applied to discover core targets and therapeutic compounds in other diseases.
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Affiliation(s)
- Zhe Yu
- Institute of Integrative Medicine, Department of Integrated Traditional Chinese and Western Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- NATCM Key Laboratory of TCM Gan, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- Center for Interdisciplinary Research in Traditional Chinese Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
| | - Ruoqi Ding
- Institute of Integrative Medicine, Department of Integrated Traditional Chinese and Western Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- NATCM Key Laboratory of TCM Gan, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- Center for Interdisciplinary Research in Traditional Chinese Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
| | - Qiuju Yan
- Institute of Integrative Medicine, Department of Integrated Traditional Chinese and Western Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- NATCM Key Laboratory of TCM Gan, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- Center for Interdisciplinary Research in Traditional Chinese Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
| | - Menghan Cheng
- Institute of Integrative Medicine, Department of Integrated Traditional Chinese and Western Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- NATCM Key Laboratory of TCM Gan, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- Center for Interdisciplinary Research in Traditional Chinese Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
| | - Teng Li
- Institute of Integrative Medicine, Department of Integrated Traditional Chinese and Western Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- NATCM Key Laboratory of TCM Gan, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- Center for Interdisciplinary Research in Traditional Chinese Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- Xiangya Hospital, Central South University, Nanchang, Jiangxi, 330004, People’s Republic of China
| | - Fei Zheng
- The College of Integrated Traditional Chinese and Western Medicine, Hunan University of Chinese Medicine, Changsha, 410008, People’s Republic of China
| | - Lin Zhu
- Institute of Integrative Medicine, Department of Integrated Traditional Chinese and Western Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- NATCM Key Laboratory of TCM Gan, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- Center for Interdisciplinary Research in Traditional Chinese Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- Xiangya Hospital, Central South University, Nanchang, Jiangxi, 330004, People’s Republic of China
| | - Yang Wang
- Institute of Integrative Medicine, Department of Integrated Traditional Chinese and Western Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- NATCM Key Laboratory of TCM Gan, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- Center for Interdisciplinary Research in Traditional Chinese Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- Xiangya Hospital, Central South University, Nanchang, Jiangxi, 330004, People’s Republic of China
| | - Tao Tang
- Institute of Integrative Medicine, Department of Integrated Traditional Chinese and Western Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- NATCM Key Laboratory of TCM Gan, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- Center for Interdisciplinary Research in Traditional Chinese Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- Xiangya Hospital, Central South University, Nanchang, Jiangxi, 330004, People’s Republic of China
| | - En Hu
- Institute of Integrative Medicine, Department of Integrated Traditional Chinese and Western Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- NATCM Key Laboratory of TCM Gan, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- Center for Interdisciplinary Research in Traditional Chinese Medicine, Xiangya Hospital, Central South University, Changsha, 410008, People’s Republic of China
- Xiangya Hospital, Central South University, Nanchang, Jiangxi, 330004, People’s Republic of China
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Liu T, Zhu W, Zhang X, He C, Liu X, Xin Q, Chen K, Wang H. Recent Advances in Cell and Functional Biomaterial Treatment for Spinal Cord Injury. BIOMED RESEARCH INTERNATIONAL 2022; 2022:5079153. [PMID: 35978649 PMCID: PMC9377911 DOI: 10.1155/2022/5079153] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 07/17/2022] [Accepted: 07/25/2022] [Indexed: 12/17/2022]
Abstract
Spinal cord injury (SCI) is a devastating central nervous system disease caused by accidental events, resulting in loss of sensory and motor function. Considering the multiple effects of primary and secondary injuries after spinal cord injury, including oxidative stress, tissue apoptosis, inflammatory response, and neuronal autophagy, it is crucial to understand the underlying pathophysiological mechanisms, local microenvironment changes, and neural tissue functional recovery for preparing novel treatment strategies. Treatment based on cell transplantation has become the forefront of spinal cord injury therapy. The transplanted cells provide physical and nutritional support for the damaged tissue. At the same time, the implantation of biomaterials with specific biological functions at the site of the SCI has also been proved to improve the local inhibitory microenvironment and promote axonal regeneration, etc. The combined transplantation of cells and functional biomaterials for SCI treatment can result in greater neuroprotective and regenerative effects by regulating cell differentiation, enhancing cell survival, and providing physical and directional support for axon regeneration and neural circuit remodeling. This article reviews the pathophysiology of the spinal cord, changes in the microenvironment after injury, and the mechanisms and strategies for spinal cord regeneration and repair. The article will focus on summarizing and discussing the latest intervention models based on cell and functional biomaterial transplantation and the latest progress in combinational therapies in SCI repair. Finally, we propose the future prospects and challenges of current treatment regimens for SCI repair, to provide references for scientists and clinicians to seek better SCI repair strategies in the future.
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Affiliation(s)
- Tianyi Liu
- Department of Neurosurgery, First Hospital of Jilin University, Changchun 130021, China
| | - Wenhao Zhu
- Department of Neurosurgery, First Hospital of Jilin University, Changchun 130021, China
| | - Xiaoyu Zhang
- Department of Neurosurgery, First Hospital of Jilin University, Changchun 130021, China
| | - Chuan He
- Department of Neurosurgery, First Hospital of Jilin University, Changchun 130021, China
| | - Xiaolong Liu
- Department of Neurosurgery, First Hospital of Jilin University, Changchun 130021, China
| | - Qiang Xin
- Department of Neurosurgery, First Hospital of Jilin University, Changchun 130021, China
| | - Kexin Chen
- Institute of Translational Medicine, First Hospital of Jilin University, Changchun 130021, China
| | - Haifeng Wang
- Department of Neurosurgery, First Hospital of Jilin University, Changchun 130021, China
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3
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Li ZW, Zhao JJ, Li SY, Cao TT, Wang Y, Guo Y, Xi GJ. Blocking the EGFR/p38/NF-κB signaling pathway alleviates disruption of BSCB and subsequent inflammation after spinal cord injury. Neurochem Int 2021; 150:105190. [PMID: 34537318 DOI: 10.1016/j.neuint.2021.105190] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 09/14/2021] [Accepted: 09/15/2021] [Indexed: 10/20/2022]
Abstract
Epidermal growth factor receptor (EGFR) activation is involved in blood spinal cord barrier (BSCB) disruption and secondary injury after spinal cord injury (SCI). However, the underlying mechanisms of EGFR activation mediating BSCB disruption and secondary injury after SCI remain unclear. An in vitro model of oxygen and glucose deprivation/reoxygenation (OGD/R) induced BSCB damage and in vivo rat SCI model were employed to define the role of EGFR/p38/NF-κB signal pathway activation and its induced inflammatory injury in main cellular components of BSCB. Genetic regulation (lentivirus delivered shRNA and overexpression system) or chemical intervention (agonist or inhibitor) were applied to activate or inactivate EGFR and p38 in astrocytes and microvascular endothelial cells (MEC) under which conditions, the expression of pro-inflammatory factors (TNF-α, iNOS, COX-2, and IL-1β), tight junction (TJ) protein (ZO-1 and occludin), nuclear translocation of NF-κB and permeability of BSCB were analyzed. The pEGFR was increased in astrocytes and MEC which induced the activation of EGFR and p38 and NF-κB nuclear translocation. The activation of EGFR and p38 increased the TNF-α, iNOS, COX-2, and IL-1β responsible for the inflammatory injury and reduced the ZO-1 and occludin which caused BSCB disruption. While EGFR or p38 inactivation inhibited NF-κB nuclear translocation, and markedly attenuated the production of pro-inflammatory factors and the loss of TJ protein. This study suggests that the EGFR activation in main cellular components of BSCB after SCI mediates BSCB disruption and secondary inflammatory injury via the EGFR/p38/NF-κB pathway.
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Affiliation(s)
- Zai-Wang Li
- Department of Neurology, Shenzhen People's Hospital, The Second Clinical Medical College of Jinan University, The First Affiliated Hospital of Southern University of Science and Technology, Shenzhen, 518020, PR China.
| | - Jing-Jing Zhao
- Center of Clinical Research, The Affiliated Wuxi People's Hospital of Nanjing Medical University, Wuxi, 214023, PR China
| | - Su-Ya Li
- Department of Neurology, Shanghai Fourth People's Hospital, School of Medicine, Tongji University, Shanghai, 200434, PR China
| | - Ting-Ting Cao
- Department of Neurology, Yancheng First People's Hospital, Yancheng, 224001, PR China
| | - Yi Wang
- University of Traditional Chinese Medicine, Kunming, 650500, PR China; Otolaryngological Department, Yunnan Province Traditional Chinese Medicine, Hospital of Yunnan University of Traditional Chinese Medicine, Kunming, 650500, PR China
| | - Yi Guo
- Department of Neurology, Shenzhen People's Hospital, The Second Clinical Medical College of Jinan University, The First Affiliated Hospital of Southern University of Science and Technology, Shenzhen, 518020, PR China
| | - Guang-Jun Xi
- Department of Neurology, Shanghai Fourth People's Hospital, School of Medicine, Tongji University, Shanghai, 200434, PR China.
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4
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Zeb2 Is a Regulator of Astrogliosis and Functional Recovery after CNS Injury. Cell Rep 2021; 31:107834. [PMID: 32610135 DOI: 10.1016/j.celrep.2020.107834] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 05/20/2020] [Accepted: 06/09/2020] [Indexed: 01/06/2023] Open
Abstract
The astrocytic response to injury is characterized on the cellular level, but our understanding of the molecular mechanisms controlling the cellular processes is incomplete. The astrocytic response to injury is similar to wound-healing responses in non-neural tissues that involve epithelial-to-mesenchymal transitions (EMTs) and upregulation in ZEB transcription factors. Here we show that injury-induced astrogliosis increases EMT-related genes expression, including Zeb2, and long non-coding RNAs, including Zeb2os, which facilitates ZEB2 protein translation. In mouse models of either contusive spinal cord injury or transient ischemic stroke, the conditional knockout of Zeb2 in astrocytes attenuates astrogliosis, generates larger lesions, and delays the recovery of motor function. These findings reveal ZEB2 as an important regulator of the astrocytic response to injury and suggest that astrogliosis is an EMT-like process, which provides a conceptual connection for the molecular and cellular similarities between astrogliosis and wound-healing responses in non-neural tissue.
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5
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Liu J, Li R, Huang Z, Lin J, Ji W, Huang Z, Liu Q, Wu X, Wu X, Jiang H, Ye Y, Zhu Q. Rapamycin Preserves Neural Tissue, Promotes Schwann Cell Myelination and Reduces Glial Scar Formation After Hemi-Contusion Spinal Cord Injury in Mice. Front Mol Neurosci 2021; 13:574041. [PMID: 33551740 PMCID: PMC7862581 DOI: 10.3389/fnmol.2020.574041] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 10/23/2020] [Indexed: 11/13/2022] Open
Abstract
Protecting white matter is one of the key treatment strategies for spinal cord injury (SCI), including alleviation of myelin loss and promotion of remyelination. Rapamycin has been shown neuroprotective effects against SCI and cardiotoxic effects while enhancing autophagy. However, specific neuroprotection of rapamycin for the white matter after cervical SCI has not been reported. Therefore, we aim to evaluate the role of rapamycin in neuroprotection after hemi-contusion SCI in mice. Forty-six 8-week-old mice were randomly assigned into the rapamycin group (n = 16), vehicle group (n = 16), and sham group (n = 10). All mice of the rapamycin and vehicle groups received a unilateral contusion with 1.2-mm displacement at C5 followed by daily intraperitoneal injection of rapamycin or dimethyl sulfoxide solution (1.5 mg⋅kg-1⋅day-1). The behavioral assessment was conducted before the injury, 3 days and every 2 weeks post-injury (WPI). The autophagy-related proteins, the area of spared white matter, the number of oligodendrocytes (OLs) and axons were evaluated at 12 WPI, as well as the glial scar and the myelin sheaths formed by Schwann cells at the epicenter. The 1.2 mm contusion led to a consistent moderate-severe SCI in terms of motor function and tissue damage. Rapamycin administration promoted autophagy in spinal cord tissue after injury and reduced the glial scar at the epicenter. Additionally, rapamycin increased the number of OLs and improved motor function significantly than in the vehicle group. Furthermore, the rapamycin injection resulted in an increase of Schwann cell-mediated remyelination and weight loss. Our results suggest that rapamycin can enhance autophagy, promote Schwann cell myelination and motor function recovery by preserved neural tissue, and reduce glial scar after hemi-contusive cervical SCI, indicating a potential strategy for SCI treatment.
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Affiliation(s)
- Junhao Liu
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China.,Division of Spine Surgery, Department of Orthopaedics, Guangzhou First People's Hospital, School of Medicine, South China University of Technology, Guangzhou, China
| | - Ruoyao Li
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Zucheng Huang
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Junyu Lin
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Wei Ji
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Zhiping Huang
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Qi Liu
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Xiaoliang Wu
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Xiuhua Wu
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Hui Jiang
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Yongnong Ye
- Pharmaceutical Department, Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou, China
| | - Qingan Zhu
- Division of Spine Surgery, Department of Orthopaedics, Nanfang Hospital, Southern Medical University, Guangzhou, China
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6
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Tavassoly O, Sato T, Tavassoly I. Inhibition of Brain Epidermal Growth Factor Receptor Activation: A Novel Target in Neurodegenerative Diseases and Brain Injuries. Mol Pharmacol 2020; 98:13-22. [DOI: 10.1124/mol.120.119909] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 04/10/2020] [Indexed: 12/20/2022] Open
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7
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Sutherland TC, Geoffroy CG. The Influence of Neuron-Extrinsic Factors and Aging on Injury Progression and Axonal Repair in the Central Nervous System. Front Cell Dev Biol 2020; 8:190. [PMID: 32269994 PMCID: PMC7109259 DOI: 10.3389/fcell.2020.00190] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 03/06/2020] [Indexed: 12/21/2022] Open
Abstract
In the aging western population, the average age of incidence for spinal cord injury (SCI) has increased, as has the length of survival of SCI patients. This places great importance on understanding SCI in middle-aged and aging patients. Axon regeneration after injury is an area of study that has received substantial attention and made important experimental progress, however, our understanding of how aging affects this process, and any therapeutic effort to modulate repair, is incomplete. The growth and regeneration of axons is mediated by both neuron intrinsic and extrinsic factors. In this review we explore some of the key extrinsic influences on axon regeneration in the literature, focusing on inflammation and astrogliosis, other cellular responses, components of the extracellular matrix, and myelin proteins. We will describe how each element supports the contention that axonal growth after injury in the central nervous system shows an age-dependent decline, and how this may affect outcomes after a SCI.
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Affiliation(s)
- Theresa C Sutherland
- Department of Neuroscience and Experimental Therapeutics, Texas A&M Health Science Center, Bryan, TX, United States
| | - Cédric G Geoffroy
- Department of Neuroscience and Experimental Therapeutics, Texas A&M Health Science Center, Bryan, TX, United States
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8
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He Y, Liu X, Chen Z. Glial Scar-a Promising Target for Improving Outcomes After CNS Injury. J Mol Neurosci 2019; 70:340-352. [PMID: 31776856 DOI: 10.1007/s12031-019-01417-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 10/10/2019] [Indexed: 12/14/2022]
Abstract
After central nervous system (CNS) injury, a series of stress responses induce astrocytes activation. Reactive astrocytes, which are typically different from astrocytes in normal conditions in altered morphology and gene expression, combine with extracellular matrix (ECM) components to form a glial scar at the lesion site, which walls of the injured region from neighboring healthier tissue. However, as a physical and molecular barrier, glial scar can impede patients' functional recovery in the late period of CNS injury. Thus, inhibiting glial scar formation in the chronic stage after CNS injury may be a promising target to improve outcomes. Since the therapeutic strategies targeting on mediating glial scar formation are regarded as an important part on improving functional recovery after CNS injury, in this review, we focus on the regulating effects of related signaling pathways and other molecules on glial scar, and the process of glial scar formation and the roles that it plays during the acute and chronic stages are also expounded in this article. We hope to get a comprehensive understanding of glial scar during CNS injury based on current researches and to open new perspectives for the therapies to promote functional recovery after CNS injury.
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Affiliation(s)
- Yuanyuan He
- Department of Pharmacy, Xuyi People's Hospital, 28 Hongwu Road, Xuyi, 211700, Jiangsu, People's Republic of China
| | - Xiaoyan Liu
- Department of Pharmacy, Xuyi People's Hospital, 28 Hongwu Road, Xuyi, 211700, Jiangsu, People's Republic of China
| | - Zhongying Chen
- Department of Pharmacy, Xuyi People's Hospital, 28 Hongwu Road, Xuyi, 211700, Jiangsu, People's Republic of China.
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Li G, Fan ZK, Gu GF, Jia ZQ, Zhang QQ, Dai JY, He SS. Epidural Spinal Cord Stimulation Promotes Motor Functional Recovery by Enhancing Oligodendrocyte Survival and Differentiation and by Protecting Myelin after Spinal Cord Injury in Rats. Neurosci Bull 2019; 36:372-384. [PMID: 31732865 DOI: 10.1007/s12264-019-00442-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 07/23/2019] [Indexed: 02/06/2023] Open
Abstract
Epidural spinal cord stimulation (ESCS) markedly improves motor and sensory function after spinal cord injury (SCI), but the underlying mechanisms are unclear. Here, we investigated whether ESCS affects oligodendrocyte differentiation and its cellular and molecular mechanisms in rats with SCI. ESCS improved hindlimb motor function at 7 days, 14 days, 21 days, and 28 days after SCI. ESCS also significantly increased the myelinated area at 28 days, and reduced the number of apoptotic cells in the spinal white matter at 7 days. SCI decreased the expression of 2',3'-cyclic-nucleotide 3'-phosphodiesterase (CNPase, an oligodendrocyte marker) at 7 days and that of myelin basic protein at 28 days. ESCS significantly upregulated these markers and increased the percentage of Sox2/CNPase/DAPI-positive cells (newly differentiated oligodendrocytes) at 7 days. Recombinant human bone morphogenetic protein 4 (rhBMP4) markedly downregulated these factors after ESCS. Furthermore, ESCS significantly decreased BMP4 and p-Smad1/5/9 expression after SCI, and rhBMP4 reduced this effect of ESCS. These findings indicate that ESCS enhances the survival and differentiation of oligodendrocytes, protects myelin, and promotes motor functional recovery by inhibiting the BMP4-Smad1/5/9 signaling pathway after SCI.
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Affiliation(s)
- Gang Li
- Department of Orthopedics, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, 200072, China
- Spinal Pain Research Institute, Tongji University School of Medicine, Shanghai, 200072, China
| | - Zhong-Kai Fan
- Department of Orthopaedics, The First Affiliated Hospital, Jinzhou Medical University, Jinzhou, 121001, China
| | - Guang-Fei Gu
- Department of Orthopedics, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, 200072, China
- Spinal Pain Research Institute, Tongji University School of Medicine, Shanghai, 200072, China
| | - Zhi-Qiang Jia
- Department of Spinal Surgery, The Second Affiliated Hospital, Henan University of Science and Technology, Luoyang, 471003, China
| | - Qiang-Qiang Zhang
- Department of Orthopaedics, The First Affiliated Hospital, Jinzhou Medical University, Jinzhou, 121001, China
| | - Jun-Yu Dai
- Department of Orthopaedics, The First Affiliated Hospital, Jinzhou Medical University, Jinzhou, 121001, China
| | - Shi-Sheng He
- Department of Orthopedics, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, 200072, China.
- Spinal Pain Research Institute, Tongji University School of Medicine, Shanghai, 200072, China.
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10
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Li B, Wang Z, Yu M, Wang X, Wang X, Chen C, Zhang Z, Zhang M, Sun C, Zhao C, Li Q, Wang W, Wang T, Zhang L, Ning G, Feng S. miR-22-3p enhances the intrinsic regenerative abilities of primary sensory neurons via the CBL/p-EGFR/p-STAT3/GAP43/p-GAP43 axis. J Cell Physiol 2019; 235:4605-4617. [PMID: 31663116 DOI: 10.1002/jcp.29338] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 09/30/2019] [Indexed: 02/06/2023]
Abstract
Spinal cord injury (SCI) is a devastating disease. Strategies that enhance the intrinsic regenerative ability are very important for the recovery of SCI to radically prevent the occurrence of sensory disorders. Epidermal growth factor (EGF) showed a limited effect on the growth of primary sensory neuron neurites due to the degradation of phosphorylated-epidermal growth factor receptor (p-EGFR) in a manner dependent on Casitas B-lineage lymphoma (CBL) (an E3 ubiquitin-protein ligase). MiR-22-3p predicted from four databases could target CBL to inhibit the expression of CBL, increase p-EGFR levels and neurites length via STAT3/GAP43 pathway rather than Erk1/2 axis. EGF, EGFR, and miR-22-3p were downregulated sharply after injury. In vivo miR-22-3p Agomir application could regulate CBL/p-EGFR/p-STAT3/GAP43/p-GAP43 axis, and restore spinal cord sensory conductive function. This study clarified the mechanism of the limited promotion effect of EGF on adult primary sensory neuron neurite and targeting miR-22-3p could be a novel strategy to treat sensory dysfunction after SCI.
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Affiliation(s)
- Bo Li
- Department of Orthopedics, Tianjin Medical University General Hospital, 154 Anshan Road, Heping District, Tianjin, 300052, China
| | - Zhijie Wang
- Department of Pediatric Internal Medicine, Affiliated Hospital of Chengde Medical University, Chengde, 067000, Hebei, China
| | - Mei Yu
- Department of Leukemia Center, Chinese Academy of Medical Sciences & Peking Union of Medical College, Institute of Hematology & Hospital of Blood Diseases, Tianjin, 30020, China
| | - Xu Wang
- Department of Orthopedics, Tianjin Medical University General Hospital, 154 Anshan Road, Heping District, Tianjin, 300052, China
| | - Xin Wang
- Department of Graduate School, Chengde Medical University, Chengde, Hebei, 067000, China
| | - Chuanjie Chen
- Department of Orthopedics, Chengde Central Hospital, Chengde, 067000, Hebei, China
| | - Zheng Zhang
- Department of Orthopedics, The 981st Hospital of the Chinese People's Liberation Army Joint Logistics Support Force, Chengde, 067000, Hebei, China
| | - Meiling Zhang
- Department of Graduate School, Chengde Medical University, Chengde, Hebei, 067000, China
| | - Chao Sun
- Department of Orthopedics, Tianjin Medical University General Hospital, 154 Anshan Road, Heping District, Tianjin, 300052, China
| | - Chenxi Zhao
- Department of Orthopedics, Tianjin Medical University General Hospital, 154 Anshan Road, Heping District, Tianjin, 300052, China
| | - Qiang Li
- Department of Orthopedics, Tianjin Medical University General Hospital, 154 Anshan Road, Heping District, Tianjin, 300052, China.,Department of Orthopedics, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Taiyuan, 030032, Shanxi, China
| | - Wei Wang
- Department of Orthopedics, Tianjin Medical University General Hospital, 154 Anshan Road, Heping District, Tianjin, 300052, China
| | - Tianyi Wang
- Department of Orthopedics, The 981st Hospital of the Chinese People's Liberation Army Joint Logistics Support Force, Chengde, 067000, Hebei, China
| | - Liang Zhang
- Department of Orthopedics, The Second Hospital of Tianjin Medical University, Tianjin, 300211, China
| | - Guangzhi Ning
- Department of Orthopedics, Tianjin Medical University General Hospital, 154 Anshan Road, Heping District, Tianjin, 300052, China.,Department of Translational Medicine, International Science and Technology Cooperation Base of Spinal Cord Injury, Tianjin Key Laboratory of Spine and Spinal Cord Injury, 154 Anshan Road, Heping District, Tianjin, 300052, China
| | - Shiqing Feng
- Department of Orthopedics, Tianjin Medical University General Hospital, 154 Anshan Road, Heping District, Tianjin, 300052, China.,Department of Translational Medicine, International Science and Technology Cooperation Base of Spinal Cord Injury, Tianjin Key Laboratory of Spine and Spinal Cord Injury, 154 Anshan Road, Heping District, Tianjin, 300052, China
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11
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Madadi S, Pasbakhsh P, Tahmasebi F, Mortezaee K, Khanehzad M, Boroujeni FB, Noorzehi G, Kashani IR. Astrocyte ablation induced by La-aminoadipate (L-AAA) potentiates remyelination in a cuprizone demyelinating mouse model. Metab Brain Dis 2019; 34:593-603. [PMID: 30652255 DOI: 10.1007/s11011-019-0385-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 01/07/2019] [Indexed: 12/14/2022]
Abstract
Chronic demyelination in the central nervous system (CNS) is accompanied by an increase in the number of reactive astrocytes and astrogliosis. There are controversial issues regarding astrocytes and their roles in demyelinating diseases in particular for multiple sclerosis (MS). We aimed to evaluate possible roles for pharmacologic astrocyte ablation strategy using La-aminoadipate (L-AAA) on remyelination in a cuprizone model of demyelination. Male C57BL/6 mice were fed with 0.2% cuprizone for 12 weeks followed by 2-week administration of L-AAA through a cannula inserted 1 mm above the corpus callosum. Rotarod test showed a significant decrease in the range of motor coordination deficits after ablation of astrocytes in mice receiving cuprizone. Results of Luxol fast blue (LFB) and transmission electron microscopy (TEM) for evaluation of myelin content within the corpus callosum revealed a noticeable rise in the percentage of myelinated areas and in the number of myelinated fibers after L-AAA administration in the animals. Astrocyte ablation reduced protein expressions for GFAP (an astrocyte marker) and Iba-1 (a microglial marker), but increased expression of Olig2 (an oligodendrocyte marker) assessed by immunofluorescence. Finally, expression of genes related to recruitment of microglia (astrocyte chemokines CXCL10 and CXCL12) and suppression of oligodendrocyte progenitor cell (OPC) differentiation (astrocyte peptides ET-1 and EDNRB) showed a considerable decrease after administration of L-AAA (for all p < 0.05). These results are indicative of improved remyelination after ablation of astrocytes possibly through hampering microgliosis and astrogliosis and a further rise in the number of matured Olig2+ cells.
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Affiliation(s)
- Soheila Madadi
- Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Poursina Street, Tehran, Iran
| | - Parichehr Pasbakhsh
- Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Poursina Street, Tehran, Iran
| | - Fatemeh Tahmasebi
- Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Poursina Street, Tehran, Iran
| | - Keywan Mortezaee
- Department of Anatomy, School of Medicine, Kurdistan University of Medical Sciences, Sanandaj, Iran
| | - Maryam Khanehzad
- Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Poursina Street, Tehran, Iran
| | - Fatemeh Beigi Boroujeni
- Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Poursina Street, Tehran, Iran
| | - Golaleh Noorzehi
- Laboratory Technology Faculty, Khatam Al-Nabieen University, Kabul, Afghanistan
| | - Iraj Ragerdi Kashani
- Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Poursina Street, Tehran, Iran.
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12
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A Causal Relationship in Spinal Cord Injury Rat Model Between Microglia Activation and EGFR/MAPK Detected by Overexpression of MicroRNA-325-3p. J Mol Neurosci 2019; 68:181-190. [PMID: 30911940 DOI: 10.1007/s12031-019-01297-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 03/11/2019] [Indexed: 02/06/2023]
Abstract
Microglial activation and inflammatory response played an important role in the secondary injury of spinal cord injury (SCI). Several microRNAs were associated with this procedure, but the underlying molecular mechanism was poorly understood. Sprague-Dawley (SD) rats were divided into four groups: SCI group (n = 7), agomiR-325-3p group (n = 7), and their control groups. Expression of miR-325-3p and proteins in epidermal growth factor receptor (EGFR)/mitogen-activated protein kinase (MAPK) signaling pathway was evaluated in microglia from SCI rats and primary microglia/BV2 cells activated by lipopolysaccharide (LPS). Concentrations of interleukin-1β (IL-1β) and tumor necrosis factor α (TNF-α) in supernatants were measured by ELISA. Low expression of miR-325-3p and activation of EGFR/MAPK was observed in microglia of SCI and LPS-induced primary microglia. Overexpression of miR-325-3p in LPS-induced BV2 cells inhibited microglial activation and release of TNF-α and IL-1β. Luciferase reporter assay confirmed that miR-325-3p negatively regulated EGFR by targeting its 3'-untranslated regions. Additionally, agomiR-325-3p inhibited the activation of microglia and EGFR/MAPK, alleviating the inflammatory response. These results indicated that miR-325-3p attenuated secondary injury after SCI through inhibition of EGFR/MAPK signaling pathway, the microglial activation, and the release of inflammatory cytokines, suggesting that miR-325-3p may be employed as a therapeutic target for SCI.
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13
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Fan C, Li X, Zhao Y, Xiao Z, Xue W, Sun J, Li X, Zhuang Y, Chen Y, Dai J. Cetuximab and Taxol co-modified collagen scaffolds show combination effects for the repair of acute spinal cord injury. Biomater Sci 2018; 6:1723-1734. [PMID: 29845137 DOI: 10.1039/c8bm00363g] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Injury-activated endogenous neural stem cells (NSCs) in the spinal cord have promising therapeutic applications for rebuilding the neuronal relays after spinal cord injury (SCI) because of their lack of immune-rejection following exogenous cell transplantation. However, these NSCs rarely differentiate into neurons and the damaged axonal regenerative ability is drastically reduced due to the adverse SCI microenvironment. Cetuximab, an EGFR signaling antagonist, has demonstrated the ability of promoting NSC differentiation into neurons. Taxol, in addition to stabilizing microtubules, has shown potential for enhancing axonal regeneration and reducing scar formation after SCI. In this study, we further verified the combined therapeutic effects of Cetuximab and Taxol on inhibition of scar deposition and promotion of neuronal differentiation, axonal outgrowth and functional recovery in a rat severe SCI model. A linear orderly collagen scaffold modified with Cetuximab and Taxol was grafted into the SCI site after the complete removal of 4 mm of spinal tissue. The results showed that the combined functional scaffold implantation significantly increased neural regeneration to reconnect the neural network. Moreover, scaffold transplantation decreases the deposition of varied scar-related inhibitors within the lesion center, further reflecting the need for a combination dedicated to increasing motor function following SCI. Collagen scaffold based-combined therapy provides a potential strategy for improving functional restoration of the injured spinal cord.
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Affiliation(s)
- Caixia Fan
- CAS Key Laboratory for Nano-Bio Interface Research, Division of Nanobiomedicine, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China.
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14
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Ozturk AM, Sozbilen MC, Sevgili E, Dagci T, Özyalcin H, Armagan G. Epidermal growth factor regulates apoptosis and oxidative stress in a rat model of spinal cord injury. Injury 2018; 49:1038-1045. [PMID: 29602490 DOI: 10.1016/j.injury.2018.03.021] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Revised: 02/13/2018] [Accepted: 03/20/2018] [Indexed: 02/02/2023]
Abstract
Spinal cord injury (SCI) leads to vascular damage and disruption of blood-spinal cord barrier which participates in secondary nerve injury. Epidermal growth factor (EGF) is an endogenous protein which regulates cell proliferation, growth and differention. Previous studies reported that EGF exerts neuroprotective effect in spinal cord after SCI. However, the molecular mechanisms underlying EGF-mediated protection in different regions of nervous system have not shown yet. In this study, we aimed to examine possible anti-apoptotic and protective roles of EGF not only in spinal cord but also in brain following SCI. Twenty-eight adult rats were divided into four groups of seven animals each as follows: sham, trauma (SCI), SCI + EGF and SCI + methylprednisolone (MP) groups. The functional neurological deficits due to the SCI were assessed by behavioral analysis using the Basso, Beattie and Bresnahan (BBB) open-field locomotor test. The alterations in pro-/anti-apoptotic protein levels and antioxidant enzyme activities were measured in spinal cord and frontal cortex. In our study, EGF promoted locomotor recovery and motor neuron survival of SCI rats. EGF treatment significantly decreased Bax and increased Bcl-2 protein expressions both in spinal cord and brain when compared to SCI group. Moreover, antioxidant enzyme activities including catalase, superoxide dismutase (SOD) and glutathione peroxidase (GPx) were increased following EGF treatment similar to MP treatment. Our experiment also suggests that alteration of the ratio of Bcl-2 to Bax may result from decreased apoptosis following EGF treatment. As a conclusion, these results show, for the first time, that administration of EGF exerts its protection via regulating apoptotic and oxidative pathways in response to spinal cord injury in different regions of central nervous system.
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Affiliation(s)
- Anil Murat Ozturk
- Department of Orthopaedic Surgery, School of Medicine Hospital, Ege University, Bornova, Izmir, Turkey.
| | - Murat Celal Sozbilen
- Department of Orthopaedics and Traumatology, Dr Behcet Uz Child Diseases and Surgery Research and Training Hospital, Konak, Izmir, Turkey
| | - Elvin Sevgili
- Department of Biochemistry, Faculty of Pharmacy, Ege University, Bornova, Izmir, Turkey
| | - Taner Dagci
- Department of Physiology, School of Medicine, Ege University, Bornova, Izmir, Turkey; Center for Brain Research, Ege University, Bornova, Izmir, Turkey
| | - Halit Özyalcin
- Department of Orthopaedic Surgery, School of Medicine Hospital, Ege University, Bornova, Izmir, Turkey
| | - Guliz Armagan
- Department of Biochemistry, Faculty of Pharmacy, Ege University, Bornova, Izmir, Turkey
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15
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Inhibition of miR-21 ameliorates excessive astrocyte activation and promotes axon regeneration following optic nerve crush. Neuropharmacology 2018; 137:33-49. [PMID: 29709341 DOI: 10.1016/j.neuropharm.2018.04.028] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 04/18/2018] [Accepted: 04/26/2018] [Indexed: 12/15/2022]
Abstract
Optic nerve injury is a leading cause of irreversible visual impairment worldwide and can even cause blindness. Excessive activation of astrocytes has negative effects on the repair and recovery of retinal ganglion cells following optic nerve injury. However, the molecular and cellular mechanisms underlying astrocyte activation after optic nerve injury remain largely unknown. In the present study, we explored the effects of microRNA-21 (miR-21) on axon regeneration and flash visual evoked potential (F-VEP) and the underlying mechanisms of these effects based on astrocyte activation in the rat model of optic nerve crush (ONC). To the best of our knowledge, this article is the first to report that inhibition of miR-21 enhances axonal regeneration and promotes functional recovery in F-VEP in the rat model of ONC. Furthermore, inhibition of miR-21 attenuates excessive astrocyte activation and glial scar formation, thereby promoting axonal regeneration by regulating the epidermal growth factor receptor (EGFR) pathway. In addition, we observed that the expression of tissue inhibitor of metalloproteinase-3, a target gene of miR-21, was inhibited during this process. Taken together, these findings demonstrate that inhibition of miR-21 regulates the EGFR pathway, ameliorating excessive astrocyte activation and glial scar progression and promoting axonal regeneration and alleviating impairment in F-VEP function in a model of ONC. This study's results suggest that miR-21 may represent a therapeutic target for optic nerve injury.
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16
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Chen NF, Sung CS, Wen ZH, Chen CH, Feng CW, Hung HC, Yang SN, Tsui KH, Chen WF. Therapeutic Effect of Platelet-Rich Plasma in Rat Spinal Cord Injuries. Front Neurosci 2018; 12:252. [PMID: 29740270 PMCID: PMC5924817 DOI: 10.3389/fnins.2018.00252] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 04/03/2018] [Indexed: 11/13/2022] Open
Abstract
Platelet-rich plasma (PRP) is prepared by centrifuging fresh blood in an anticoagulant state, and harvesting the platelet-rich portion or condensing platelets. Studies have consistently demonstrated that PRP concentrates are an abundant source of growth factors, such as platelet-derived growth factor (PDGF), transforming growth factor β (TGF-β), insulin-like growth factor 1 (IGF-1), and epithelial growth factor (EGF). The complex mechanisms underlying spinal cord injury (SCI) diminish intrinsic repair and neuronal regeneration. Several studies have suggested that growth factor-promoted axonal regeneration can occur for an extended period after injury. More importantly, the delivery of exogenous growth factors contained in PRP, such as EGF, IGF-1, and TGF-β, has neurotrophic effects on central nervous system (CNS) injuries and neurodegenerative diseases. However, only a few studies have investigated the effects of PRP on CNS injuries or neurodegenerative diseases. According to our review of relevant literature, no study has investigated the effect of intrathecal (i.t.) PRP injection into the injured spinal cord and activation of intrinsic mechanisms. In the present study, we directly injected i.t. PRP into rat spinal cords and examined the effects of PRP on normal and injured spinal cords. In rats with normal spinal cords, PRP induced microglia and astrocyte activation and PDGF-B and ICAM-1 expression. In rats with SCIs, i.t. PRP enhanced the locomotor recovery and spared white matter, promoted angiogenesis and neuronal regeneration, and modulated blood vessel size. Furthermore, a sustained treatment (a bolus of PRP followed by a 1/3 dose of initial PRP concentration) exerted more favorable therapeutic effects than a single dose of PRP. Our findings suggest by i.t. PRP stimulate angiogenesis, enhancing neuronal regeneration after SCI in rats. Although PRP induces minor inflammation in normal and injured spinal cords, it has many advantages. It is an autologous, biocompatible, nontoxic material that does not result in a major immune response. In addition, based on its safety and ease of preparation, we hypothesize that PRP is a promising therapeutic agent for SCI.
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Affiliation(s)
- Nan-Fu Chen
- Division of Neurosurgery, Department of Surgery, Kaohsiung Armed Forces General Hospital, Kaohsiung, Taiwan.,Department of Neurological Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Chun-Sung Sung
- Department of Anesthesiology, Taipei Veterans General Hospital, Taipei, Taiwan.,School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Zhi-Hong Wen
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-Sen University, Kaohsiung, Taiwan.,Department of Marine Biotechnology and Resources, National Sun Yat-Sen University, Kaohsiung, Taiwan
| | - Chun-Hong Chen
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-Sen University, Kaohsiung, Taiwan.,Doctoral Degree Program in Marine Biotechnology, Academia Sinica, Taipei, Taiwan
| | - Chien-Wei Feng
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-Sen University, Kaohsiung, Taiwan.,Doctoral Degree Program in Marine Biotechnology, Academia Sinica, Taipei, Taiwan
| | - Han-Chun Hung
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-Sen University, Kaohsiung, Taiwan.,Doctoral Degree Program in Marine Biotechnology, Academia Sinica, Taipei, Taiwan
| | - San-Nan Yang
- School of Medicine, College of Medicine and Department of Pediatrics, E-DA Hospital, I-Shou University, Kaohsiung, Taiwan
| | - Kuan-Hao Tsui
- Department of Obstetrics and Gynecology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.,Department of Obstetrics and Gynecology and Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.,Department of Biological Science, National Sun Yat-Sen University, Kaohsiung, Taiwan.,Department of Pharmacy and Master Program, College of Pharmacy and Health Care, Tajen University, Pingtung County, Taiwan
| | - Wu-Fu Chen
- Department of Marine Biotechnology and Resources, National Sun Yat-Sen University, Kaohsiung, Taiwan.,Department of Neurosurgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.,Department of Neurosurgery, Xiamen Chang Gung Hospital, Fujian, China
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17
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Lentiviral vector delivery of short hairpin RNA to NgR1 promotes nerve regeneration and locomotor recovery in injured rat spinal cord. Sci Rep 2018; 8:5447. [PMID: 29615686 PMCID: PMC5882972 DOI: 10.1038/s41598-018-23751-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 03/15/2018] [Indexed: 01/01/2023] Open
Abstract
Nogo receptor 1 (NgR1) is a high-affinity receptor of myelin-associated inhibitors (MAIs), and suppresses neurogenesis. Lentiviral vector are commonly used to alter the expression of targeted genes. However, little is known about the potential function of lentiviral vector harboring NgR1 shRNA (LV-NgR1 shRNA) on neurogenesis in spinal cord injury (SCI). In this study, the rats were randomly divided into three groups: including the LN (LV-NgR1 shRNA injection), LC (LV-control shRNA injection) and Sham (laminectomy only). Eight weeks post-injection of LV, spinal cords were examined by histology for changes in cavity size and by immunohistochemistry for changes in expression of NgR1, cell apoptosis, astrocytes, neurons and myelination. Motor function was assessed using the Basso, Beattie and Bresnahan (BBB) locomotor scale. Animals that received LV-NgR1 shRNA remarkably improved the motor function. These animals also showed an increase in levels of nerve fibers, synapses and myelination, a decrease in levels of lesion cavity and cell apoptosis at 8 weeks post-treatment. These findings give evidence that NgR1 may be a promising target for SCI treatment.
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18
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Liu S, Schackel T, Weidner N, Puttagunta R. Biomaterial-Supported Cell Transplantation Treatments for Spinal Cord Injury: Challenges and Perspectives. Front Cell Neurosci 2018; 11:430. [PMID: 29375316 PMCID: PMC5768640 DOI: 10.3389/fncel.2017.00430] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 12/20/2017] [Indexed: 12/17/2022] Open
Abstract
Spinal cord injury (SCI), resulting in para- and tetraplegia caused by the partial or complete disruption of descending motor and ascending sensory neurons, represents a complex neurological condition that remains incurable. Following SCI, numerous obstacles comprising of the loss of neural tissue (neurons, astrocytes, and oligodendrocytes), formation of a cavity, inflammation, loss of neuronal circuitry and function must be overcome. Given the multifaceted primary and secondary injury events that occur with SCI treatment options are likely to require combinatorial therapies. While several methods have been explored, only the intersection of two, cell transplantation and biomaterial implantation, will be addressed in detail here. Owing to the constant advance of cell culture technologies, cell-based transplantation has come to the forefront of SCI treatment in order to replace/protect damaged tissue and provide physical as well as trophic support for axonal regrowth. Biomaterial scaffolds provide cells with a protected environment from the surrounding lesion, in addition to bridging extensive damage and providing physical and directional support for axonal regrowth. Moreover, in this combinatorial approach cell transplantation improves scaffold integration and therefore regenerative growth potential. Here, we review the advances in combinatorial therapies of Schwann cells (SCs), astrocytes, olfactory ensheathing cells (OECs), mesenchymal stem cells, as well as neural stem and progenitor cells (NSPCs) with various biomaterial scaffolds.
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Affiliation(s)
- Shengwen Liu
- Spinal Cord Injury Center, Heidelberg University Hospital, Heidelberg, Germany
- Department of Neurosurgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Thomas Schackel
- Spinal Cord Injury Center, Heidelberg University Hospital, Heidelberg, Germany
| | - Norbert Weidner
- Spinal Cord Injury Center, Heidelberg University Hospital, Heidelberg, Germany
| | - Radhika Puttagunta
- Spinal Cord Injury Center, Heidelberg University Hospital, Heidelberg, Germany
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19
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Lentivirus-mediated silencing of the CTGF gene suppresses the formation of glial scar tissue in a rat model of spinal cord injury. Spine J 2018; 18:164-172. [PMID: 28089819 DOI: 10.1016/j.spinee.2017.01.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 12/14/2016] [Accepted: 01/05/2017] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT One of the many reactive changes following a spinal cord injury (SCI) is the formation of a glial scar, a reactive cellular process whereby glial cells accumulate and surround the central nervous system injury sites to seal in the wound. Thus, the inhibition of glial scar is of great importance for SCI recovery. PURPOSE This study aimed to explore the effect of lentivirus-mediated silencing of the CTGF gene on the formation of glial scar tissue in a rat model of SCI. STUDY DESIGN This is a prospective study. STUDY SAMPLE A total of 56 Wistar female rats aged 8 weeks were randomly selected for this study. OUTCOME MEASURES The motor function of the rats was assessed using the Basso, Beattie, and Bresnahan (BBB) functional scale, footprint analysis of gait, and the Basso Mouse Scale (BMS). Quantitative real-time polymerase chain reaction, Western blotting, and immunohistochemistry were performed to detect the mRNA and protein expressions of glial fibrillary acidic protein (GFAP), vimentin, fibronectin, and laminin in the spinal cord tissues. METHODS A rat model of SCI was successfully established. Fifty-six male Wistar rats were randomly selected and assigned into four groups (14 rats in each group): the sham operation group, the SCI model group, the negative control (NC) group (SCI rats transfected with empty vector plasmids), and the siRNA-CTGF group (SCI rats transfected with lentivirus CTGF siRNA). RESULTS The SCI rats showed decreased activity and were dragging their bodies while moving. Compared with the sham operation group, the BBB and BMS scores in the SCI model, NC, and siRNA-CTGF groups significantly decreased. However, the BBB and BMS scores in the siRNA-CTGF group were higher than those in the SCI model and NC groups. The mRNA and protein expressions of GFAP, vimentin, fibronectin, and laminin significantly increased in the SCI model, NC, and siRNA-CTGF groups in comparison with those in the sham operation group. Furthermore, the mRNA and protein expressions of GFAP, vimentin, fibronectin, and laminin in the siRNA-CTGF group were lower than those in the SCI model and NC groups 28 days after transfection. CONCLUSIONS These findings indicate that lentivirus-mediated silencing of the CTGF gene can suppress the formation of glial scar tissue after SCI.
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Dynasore Improves Motor Function Recovery via Inhibition of Neuronal Apoptosis and Astrocytic Proliferation after Spinal Cord Injury in Rats. Mol Neurobiol 2016; 54:7471-7482. [PMID: 27822712 DOI: 10.1007/s12035-016-0252-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 10/23/2016] [Indexed: 01/02/2023]
Abstract
Spinal cord injury (SCI) is a common and devastating central nervous system insult which lacks efficient treatment. Our previous experimental findings indicated that dynamin-related protein 1 (Drp1) mediates mitochondrial fission during SCI, and inhibition of Drp1 plays a significant protective effect after SCI in rats. Dynasore inhibits GTPase activity at both the plasma membrane (dynamin 1, 2) and the mitochondria membrane (Drp1). The aim of the present study was to investigate the beneficial effects of dynasore on SCI and its underlying mechanism in a rat model. Sprague-Dawley rats were randomly assigned to sham, SCI, and 1, 10, and 30 mg dynasore groups. The rat model of SCI was established using an established Allen's model. Dynasore was administered via intraperitoneal injection immediately. Results of motor functional test indicated that dynasore ameliorated the motor dysfunction greatly at 3, 7, and 10 days after SCI in rats (P < 0.05). Results of western blot showed that dynasore has remarkably reduced the expressions of Drp1, dynamin 1, and dynamin 2 and, moreover, decreased the Bax, cytochrome C, and active Caspase-3 expressions, but increased the expressions of Bcl-2 at 3 days after SCI (P < 0.05). Notably, the upregulation of proliferating cell nuclear antigen (PCNA) and glial fibrillary acidic protein (GAFP) are inhibited by dynasore at 3 days after SCI (P < 0.05). Results of immunofluorescent double labeling showed that there were less apoptotic neurons and proliferative astrocytes in the dynasore groups compared with SCI group (P < 0.05). Finally, histological assessment via Nissl staining demonstrated that the dynasore groups exhibited a significantly greater number of surviving neurons compared with the SCI group (P < 0.05). This neuroprotective effect was dose-dependent (P < 0.05). To our knowledge, this is the first study to indicate that dynasore significantly enhances motor function which may be by inhibiting the activation of neuronal mitochondrial apoptotic pathway and astrocytic proliferation in rats after SCI.
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21
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Li G, Cao Y, Shen F, Wang Y, Bai L, Guo W, Bi Y, Lv G, Fan Z. Mdivi-1 Inhibits Astrocyte Activation and Astroglial Scar Formation and Enhances Axonal Regeneration after Spinal Cord Injury in Rats. Front Cell Neurosci 2016; 10:241. [PMID: 27807407 PMCID: PMC5069437 DOI: 10.3389/fncel.2016.00241] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 09/30/2016] [Indexed: 11/13/2022] Open
Abstract
After spinal cord injury (SCI), astrocytes become hypertrophic, and proliferative, forming a dense network of astroglial processes at the site of the lesion. This constitutes a physical and biochemical barrier to axonal regeneration. Mitochondrial fission regulates cell cycle progression; inhibiting the cell cycle of astrocytes can reduce expression levels of axon growth-inhibitory molecules as well as astroglial scar formation after SCI. We therefore investigated how an inhibitor of mitochondrial fission, Mdivi-1, would affect astrocyte proliferation, astroglial scar formation, and axonal regeneration following SCI in rats. Western blot and immunofluorescent double-labeling showed that Mdivi-1 markedly reduced the expression of the astrocyte marker glial fibrillary acidic protein (GFAP), and a cell proliferation marker, proliferating cell nuclear antigen, in astrocytes 3 days after SCI. Moreover, Mdivi-1 decreased the expression of GFAP and neurocan, a chondroitin sulfate proteoglycan. Notably, immunofluorescent labeling and Nissl staining showed that Mdivi-1 elevated the production of growth-associated protein-43 and increased neuronal survival at 4 weeks after SCI. Finally, hematoxylin-eosin staining, and behavioral evaluation of motor function indicated that Mdivi-1 also reduced cavity formation and improved motor function 4 weeks after SCI. Our results confirm that Mdivi-1 promotes motor function after SCI, and indicate that inhibiting mitochondrial fission using Mdivi-1 can inhibit astrocyte activation and astroglial scar formation and contribute to axonal regeneration after SCI in rats.
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Affiliation(s)
- Gang Li
- Department of Orthopaedics, The First Affiliated Hospital, Jinzhou Medical University Jinzhou, China
| | - Yang Cao
- Department of Orthopaedics, The First Affiliated Hospital, Jinzhou Medical University Jinzhou, China
| | - Feifei Shen
- Department of Pathology, College of Basic Medical Sciences, China Medical University Shenyang, China
| | - Yangsong Wang
- Department of Orthopaedics, The First Affiliated Hospital, Jinzhou Medical University Jinzhou, China
| | - Liangjie Bai
- Department of Orthopaedics, The First Affiliated Hospital, China Medical University Shenyang, China
| | - Weidong Guo
- Department of Orthopaedics, The First Affiliated Hospital, Jinzhou Medical University Jinzhou, China
| | - Yunlong Bi
- Department of Orthopaedics, The First Affiliated Hospital, Jinzhou Medical University Jinzhou, China
| | - Gang Lv
- Department of Orthopaedics, The First Affiliated Hospital, Jinzhou Medical University Jinzhou, China
| | - Zhongkai Fan
- Department of Orthopaedics, The First Affiliated Hospital, Jinzhou Medical University Jinzhou, China
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22
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Goldshmit Y, Schokoroy Trangle S, Afergan F, Iram T, Pinkas-Kramarski R. Nucleolin inhibitor GroA triggers reduction in epidermal growth factor receptor activation: Pharmacological implication for glial scarring after spinal cord injury. J Neurochem 2016; 138:845-58. [PMID: 27399849 DOI: 10.1111/jnc.13730] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 06/21/2016] [Accepted: 07/05/2016] [Indexed: 12/21/2022]
Abstract
Glial scarring, formed by reactive astrocytes, is one of the major impediments for regeneration after spinal cord injury (SCI). Reactive astrocytes become hypertrophic, proliferate and secrete chondroitin sulphate proteoglycans into the extracellular matrix (ECM). Many studies have demonstrated that epidermal growth factor receptors (EGFR) can mediate astrocyte reactivity after neurotrauma. Previously we showed that there is crosstalk between nucleolin and EGFR that leads to increased EGFR activation followed by increased cell proliferation. Treatment with the nucleolin inhibitor GroA (AS1411) prevented these effects in vitro and in vivo. In this study, we hypothesized that similar interactions may mediate astrogliosis after SCI. Our results demonstrate that nucleolin and EGFR interaction may play a pivotal role in mediating astrocyte proliferation and reactivity after SCI. Moreover, we demonstrate that treatment with GroA reduces EGFR activation, astrocyte proliferation and chondroitin sulphate proteoglycans secretion, therefore promoting axonal regeneration and sprouting into the lesion site. Our results identify, for the first time, a role for the interaction between nucleolin and EGFR in astrocytes after SCI, indicating that nucleolin inhibitor GroA may be used as a novel treatment after neurotrauma. A major barrier for axonal regeneration after spinal cord injury is glial scar created by reactive and proliferating astrocytes. EGFR mediate astrocyte reactivity. We showed that inhibition of nucleolin by GroA, reduces EGFR activation, which results in attenuation of astrocyte reactivity and proliferation in vivo and in vitro. EGFR, epidermal growth factor receptor.
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Affiliation(s)
- Yona Goldshmit
- Department of Neurobiology, Tel-Aviv University, Ramat-Aviv, Israel.
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia.
| | | | - Fabian Afergan
- Department of Neurobiology, Tel-Aviv University, Ramat-Aviv, Israel
| | - Tal Iram
- Department of Neurobiology, Tel-Aviv University, Ramat-Aviv, Israel
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Zendedel A, Kashani IR, Azimzadeh M, Pasbakhsh P, Omidi N, Golestani A, Beyer C, Clarner T. Regulatory effect of triiodothyronine on brain myelination and astrogliosis after cuprizone-induced demyelination in mice. Metab Brain Dis 2016; 31:425-33. [PMID: 26725831 DOI: 10.1007/s11011-015-9781-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 12/14/2015] [Indexed: 02/02/2023]
Abstract
Chronic demyelination and plaque formation in multiple sclerosis is accompanied by persisting astrogliosis, negatively influencing central nervous system recovery and remyelination. Triiodothyronin (T3) is thought to enhance remyelination in the adult brain by the induction of oligodendrocyte maturation. We investigated additional astrocyte-mediated mechanisms by which T3 might promote remyelination in chronically demyelinated lesions using the cuprizone mouse model. C57BL/6 mice were fed cuprizone for 12 weeks to induce lesions with an impaired remyelination capacity. While the expression of oligodenrocyte progenitor markers, i.e., platelet derived growth factor-α receptor was not affected by T3 administration, myelination status, myelin protein expression as well as total and adult oligodendrocyte numbers were markedly increased compared to cuprizone treated controls. In addition to these effects on oligodendrocyte numbers and function, astrogliosis but not microgliosis was ameliorated by T3 administration. Intermediate filament proteins vimentin and nestin as well as the extracellular matrix component tenascin C were significantly reduced after T3 exposure, indicating additional effects of T3 on astrocytes and astrogliosis. Our data clearly indicate that T3 promotes remyelination in chronic lesions by both enhancing oligodendrocyte maturation and attenuating astrogliosis.
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Affiliation(s)
- Adib Zendedel
- Institute of Neuroanatomy, Faculty of Medicine, RWTH Aachen University, 52074, Aachen, Germany
- Department of Anatomical Sciences, Faculty of Medicine, Gilan University of Medical Sciences, Rasht, Iran
| | - Iraj Ragerdi Kashani
- Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
| | - Maryam Azimzadeh
- Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Parichehr Pasbakhsh
- Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Negar Omidi
- Department of Surgery, Ziaian Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Abolfazl Golestani
- Department of Biochemistry, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Cordian Beyer
- Institute of Neuroanatomy, Faculty of Medicine, RWTH Aachen University, 52074, Aachen, Germany
| | - Tim Clarner
- Institute of Neuroanatomy, Faculty of Medicine, RWTH Aachen University, 52074, Aachen, Germany
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Zhang S, Ju P, Tjandra E, Yeap Y, Owlanj H, Feng Z. Inhibition of Epidermal Growth Factor Receptor Improves Myelination and Attenuates Tissue Damage of Spinal Cord Injury. Cell Mol Neurobiol 2016; 36:1169-78. [PMID: 26883518 DOI: 10.1007/s10571-015-0313-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 11/24/2015] [Indexed: 12/11/2022]
Abstract
Preventing demyelination and promoting remyelination of denuded axons are promising therapeutic strategies for spinal cord injury (SCI). Epidermal growth factor receptor (EGFR) inhibition was reported to benefit the neural functional recovery and the axon regeneration after SCI. However, its role in de- and remyelination of axons in injured spinal cord is unclear. In the present study, we evaluated the effects of EGFR inhibitor, PD168393 (PD), on the myelination in mouse contusive SCI model. We found that expression of myelin basic protein (MBP) in the injured spinal cords of PD treated mice was remarkably elevated. The density of glial precursor cells and oligodendrocytes (OLs) was increased and the cell apoptosis in lesions was attenuated after PD168393 treatment. Moreover, PD168393 treatment reduced both the numbers of OX42 + microglial cells and glial fibrillary acidic protein + astrocytes in damaged area of spinal cords. We thus conclude that the therapeutic effects of EGFR inhibition after SCI involves facilitating remyelination of the injured spinal cord, increasing of oligodendrocyte precursor cells and OLs, as well as suppressing the activation of astrocytes and microglia/macrophages.
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Affiliation(s)
- Si Zhang
- School of Life Science and Technology, Xinxiang Medical University, Jinsui Road, Xinxiang, 453003, Henan, China.,Brain Research Center, Faculty of Medicine, University of British Columbia, Vancouver, BC, V6T 2B5, Canada
| | - Peijun Ju
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, 201108, China
| | - Editha Tjandra
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Yeeshan Yeap
- Cytogenetics Laboratory, Singapore General Hospital, Singapore, Singapore
| | - Hamed Owlanj
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Zhiwei Feng
- School of Life Science and Technology, Xinxiang Medical University, Jinsui Road, Xinxiang, 453003, Henan, China.
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Addington CP, Roussas A, Dutta D, Stabenfeldt SE. Endogenous repair signaling after brain injury and complementary bioengineering approaches to enhance neural regeneration. Biomark Insights 2015; 10:43-60. [PMID: 25983552 PMCID: PMC4429653 DOI: 10.4137/bmi.s20062] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 03/20/2015] [Accepted: 03/24/2015] [Indexed: 02/06/2023] Open
Abstract
Traumatic brain injury (TBI) affects 5.3 million Americans annually. Despite the many long-term deficits associated with TBI, there currently are no clinically available therapies that directly address the underlying pathologies contributing to these deficits. Preclinical studies have investigated various therapeutic approaches for TBI: two such approaches are stem cell transplantation and delivery of bioactive factors to mitigate the biochemical insult affiliated with TBI. However, success with either of these approaches has been limited largely due to the complexity of the injury microenvironment. As such, this review outlines the many factors of the injury microenvironment that mediate endogenous neural regeneration after TBI and the corresponding bioengineering approaches that harness these inherent signaling mechanisms to further amplify regenerative efforts.
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Affiliation(s)
- Caroline P Addington
- School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ, USA
| | - Adam Roussas
- School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ, USA
| | - Dipankar Dutta
- School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ, USA
| | - Sarah E Stabenfeldt
- School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ, USA
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Dyck SM, Karimi-Abdolrezaee S. Chondroitin sulfate proteoglycans: Key modulators in the developing and pathologic central nervous system. Exp Neurol 2015; 269:169-87. [PMID: 25900055 DOI: 10.1016/j.expneurol.2015.04.006] [Citation(s) in RCA: 123] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 04/11/2015] [Accepted: 04/14/2015] [Indexed: 12/15/2022]
Abstract
Chondroitin Sulfate Proteoglycans (CSPGs) are a major component of the extracellular matrix in the central nervous system (CNS) and play critical role in the development and pathophysiology of the brain and spinal cord. Developmentally, CSPGs provide guidance cues for growth cones and contribute to the formation of neuronal boundaries in the developing CNS. Their presence in perineuronal nets plays a crucial role in the maturation of synapses and closure of critical periods by limiting synaptic plasticity. Following injury to the CNS, CSPGs are dramatically upregulated by reactive glia which form a glial scar around the lesion site. Increased level of CSPGs is a hallmark of all CNS injuries and has been shown to limit axonal plasticity, regeneration, remyelination, and conduction after injury. Additionally, CSPGs create a non-permissive milieu for cell replacement activities by limiting cell migration, survival and differentiation. Mounting evidence is currently shedding light on the potential benefits of manipulating CSPGs in combination with other therapeutic strategies to promote spinal cord repair and regeneration. Moreover, the recent discovery of multiple receptors for CSPGs provides new therapeutic targets for targeted interventions in blocking the inhibitory properties of CSPGs following injury. Here, we will provide an in depth discussion on the impact of CSPGs in normal and pathological CNS. We will also review the recent preclinical therapies that have been developed to target CSPGs in the injured CNS.
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Affiliation(s)
- Scott M Dyck
- Regenerative Medicine Program, Department of Physiology and the Spinal Cord Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Soheila Karimi-Abdolrezaee
- Regenerative Medicine Program, Department of Physiology and the Spinal Cord Research Centre, University of Manitoba, Winnipeg, Manitoba, Canada.
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Chen X, Chen X, Huang X, Qin C, Fang Y, Liu Y, Zhang G, Pan D, Wang W, Xie M. Soluble epoxide hydrolase inhibition provides multi-target therapeutic effects in rats after spinal cord injury. Mol Neurobiol 2015; 53:1565-1578. [DOI: 10.1007/s12035-015-9118-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 01/28/2015] [Indexed: 12/19/2022]
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Abstract
Three theories of regeneration dominate neuroscience today, all purporting to explain why the adult central nervous system (CNS) cannot regenerate. One theory proposes that Nogo, a molecule expressed by myelin, prevents axonal growth. The second theory emphasizes the role of glial scars. The third theory proposes that chondroitin sulfate proteoglycans (CSPGs) prevent axon growth. Blockade of Nogo, CSPG, and their receptors indeed can stop axon growth in vitro and improve functional recovery in animal spinal cord injury (SCI) models. These therapies also increase sprouting of surviving axons and plasticity. However, many investigators have reported regenerating spinal tracts without eliminating Nogo, glial scar, or CSPG. For example, many motor and sensory axons grow spontaneously in contused spinal cords, crossing gliotic tissue and white matter surrounding the injury site. Sensory axons grow long distances in injured dorsal columns after peripheral nerve lesions. Cell transplants and treatments that increase cAMP and neurotrophins stimulate motor and sensory axons to cross glial scars and to grow long distances in white matter. Genetic studies deleting all members of the Nogo family and even the Nogo receptor do not always improve regeneration in mice. A recent study reported that suppressing the phosphatase and tensin homolog (PTEN) gene promotes prolific corticospinal tract regeneration. These findings cannot be explained by the current theories proposing that Nogo and glial scars prevent regeneration. Spinal axons clearly can and will grow through glial scars and Nogo-expressing tissue under some circumstances. The observation that deleting PTEN allows corticospinal tract regeneration indicates that the PTEN/AKT/mTOR pathway regulates axonal growth. Finally, many other factors stimulate spinal axonal growth, including conditioning lesions, cAMP, glycogen synthetase kinase inhibition, and neurotrophins. To explain these disparate regenerative phenomena, I propose that the spinal cord has evolved regenerative mechanisms that are normally suppressed by multiple extrinsic and intrinsic factors but can be activated by injury, mediated by the PTEN/AKT/mTOR, cAMP, and GSK3b pathways, to stimulate neural growth and proliferation.
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Affiliation(s)
- Wise Young
- W. M. Keck Center for Collaborative Neuroscience, Rutgers, State University of New Jersey, Piscataway, NJ, USA
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Treatment with Anti-EGF Ab Ameliorates Experimental Autoimmune Encephalomyelitis via Induction of Neurogenesis and Oligodendrogenesis. Mult Scler Int 2014; 2014:926134. [PMID: 25610650 PMCID: PMC4295609 DOI: 10.1155/2014/926134] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 12/11/2014] [Accepted: 12/12/2014] [Indexed: 01/15/2023] Open
Abstract
Background. The neural stem cells (NSCs) migrate to the damaged sites in multiple sclerosis (MS) and in experimental autoimmune encephalomyelitis (EAE). However, the differentiation into neurons or oligodendrocytes is blocked. Epidermal growth factor (EGF) stimulates NSC proliferation and mobilization to demyelinated lesions but also induces astrogenesis and glial scar. Objective. To examine the clinical and histopathological effects of EGF neutralization on EAE. Methods. EAE-induced SJL mice were intravenously treated with either anti-EGF neutralizing antibody (Ab) or isotype control or PBS. On day 9 after immunization, 3 mice of each group were daily treated for 9 days with BrdU and then sacrificed for immunohistochemical analysis. Results. Treatment with anti-EGF Ab significantly ameliorated EAE symptoms during the second relapse. Anti-EGF Ab induced a shift from BrdU+GFAP+ NSCs to BrdU+DCX+ neuroblasts in the subventricular zone (SVZ), increased BrdU+NeuN+ neurons in the granular cell layer of the dentate gyrus, and increased BrdU+O4+ oligodendrocytes in the SVZ. There was no change in the inflammatory infiltrates in response to anti-EGF Ab. Conclusions. Therapy with anti-EGF Ab ameliorates EAE via induction of neurogenesis and oligodendrogenesis. No immunosuppressive effect was found. Further investigation is needed to support these notions of beneficial effect of anti-EGF Ab in MS.
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Yang XT, Huang GH, Feng DF, Chen K. Insight into astrocyte activation after optic nerve injury. J Neurosci Res 2014; 93:539-48. [PMID: 25257183 DOI: 10.1002/jnr.23487] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 08/25/2014] [Accepted: 08/29/2014] [Indexed: 12/21/2022]
Affiliation(s)
- Xi-Tao Yang
- Department of Neurosurgery, No. 3 People's Hospital; Shanghai Jiaotong University School of Medicine; Shanghai China
| | - Guo-Hui Huang
- Department of Neurosurgery, No. 3 People's Hospital; Shanghai Jiaotong University School of Medicine; Shanghai China
| | - Dong-Fu Feng
- Department of Neurosurgery, No. 3 People's Hospital; Shanghai Jiaotong University School of Medicine; Shanghai China
- Institute of Traumatic Medicine; Shanghai Jiaotong University School of Medicine; Shanghai China
| | - Kui Chen
- Department of Neurosurgery, No. 3 People's Hospital; Shanghai Jiaotong University School of Medicine; Shanghai China
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Li ZW, Li JJ, Wang L, Zhang JP, Wu JJ, Mao XQ, Shi GF, Wang Q, Wang F, Zou J. Epidermal growth factor receptor inhibitor ameliorates excessive astrogliosis and improves the regeneration microenvironment and functional recovery in adult rats following spinal cord injury. J Neuroinflammation 2014; 11:71. [PMID: 24708754 PMCID: PMC4030311 DOI: 10.1186/1742-2094-11-71] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Accepted: 03/09/2014] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Astrogliosis is a common phenomenon after spinal cord injury (SCI). Although this process exerts positive effects on axonal regeneration, excessive astrogliosis imparts negative effects on neuronal repair and recovery. Epidermal growth factor receptor (EGFR) pathway is critical to the regulation of reactive astrogliosis, and therefore is a potential target of therapeutics to better control the response. In this report, we aim to investigate whether blocking EGFR signaling using an EGFR tyrosine kinase specific inhibitor can attenuate reactive astrogliosis and promote functional recovery after a traumatic SCI. METHOD The astrocyte scratch injury model in vitro and the weight-drop SCI model in vivo were used as model systems. PD168393 was used to inhibit EGFR signaling activation. Astrocytic activation and phosphorylated EGFR (pEGFR) were observed after immunofluorescence staining and Western blot analysis. The rate of proliferation was determined by immunofluorescence detection of BrdU-incorporating cells located next to the wound. The levels of TNF-α, iNOS, COX-2 and IL-1β in the culture medium under different conditions were assayed by ELISA. Western blot was performed to semi-quantify the expression of EGFR/pEGFR, glial fibrillary acid protein (GFAP) and chondroitin sulfate proteoglycans (CSPGs). Myelin was stained by Luxol Fast Blue Staining. Cresyl violet eosin staining was performed to analyze the lesion cavity volume and neuronal survival following injury. Finally, functional scoring and residual urine recording were performed to show the rats' recovery. RESULTS EGFR phosphorylation was found to parallel astrocyte activation, and EGFR inhibitor PD168393 potently inhibited scratch-induced reactive astrogliosis and proinflammatory cytokine/mediator secretion of reactive astrocytes in vitro. Moreover, local administration of PD168393 in the injured area suppressed CSPGs production and glial scar formation, and resulted in reduced demyelination and neuronal loss, which correlated with remarkable hindlimb motor function and bladder improvement in SCI rats. CONCLUSIONS The specific EGFR inhibitor PD168393 can ameliorate excessive reactive astrogliosis and facilitate a more favorable environment for axonal regeneration after SCI. As such, EGFR inhibitor may be a promising therapeutic intervention in CNS injury.
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Affiliation(s)
- Zai-Wang Li
- Department of Neurology, Wuxi People's Hospital of Nanjing Medical University, Wuxi, PR China.
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FOXO3a involvement in the release of TNF-α stimulated by ATP in spinal cord astrocytes. J Mol Neurosci 2013; 51:792-804. [PMID: 23860688 DOI: 10.1007/s12031-013-0067-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Accepted: 07/02/2013] [Indexed: 12/20/2022]
Abstract
Spinal cord injury is characterized by an inflammatory response that includes the increased expression of several cytokines and chemokines. Extracellular adenosine triphosphate (ATP) acts as a critical endogenous signaling molecule in inflammation and immunity. However, the molecular and cellular mechanisms of the proinflammatory cytokines stimulated by ATP are poorly understood. Mammalian forkhead members of the class O (FOXO) are involved in a variety of signaling pathways. In this study, we have found that ATP could selectively decrease the expression of FOXO1 and FOXO3a via the phosphorylation of epidermal growth factor receptor (EGFR) and Akt in spinal cord astrocytes. However, ATP had no effect on the expression of FOXO4 and FOXO6, and EGFR, Akt, and ERK1/2 all involve in the release of interleukin (IL)-6 and tumor necrosis factor-α (TNF-α) induced by ATP. In addition, we have researched that the overexpressed FOXO3a could specially inhibit the release of TNF-α increased by ATP, but the level of IL-6 induced by ATP was not decreased. Meanwhile, there was no change in the release of IL-6 and TNF-α after FOXO1 was overexpressed. Understanding the critical role of FOXO3a in astrocytes stimulated by ATP may provide a potential target for therapeutic intervention after spinal cord injury.
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Li X, Xiao Z, Han J, Chen L, Xiao H, Ma F, Hou X, Li X, Sun J, Ding W, Zhao Y, Chen B, Dai J. Promotion of neuronal differentiation of neural progenitor cells by using EGFR antibody functionalized collagen scaffolds for spinal cord injury repair. Biomaterials 2013; 34:5107-16. [PMID: 23591390 DOI: 10.1016/j.biomaterials.2013.03.062] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 03/25/2013] [Indexed: 02/08/2023]
Abstract
The main challenge for neural progenitor cell (NPC)-mediated repair of spinal cord injury (SCI) is lack of favorable environment to direct its differentiation towards neurons rather than glial cells. The myelin associated inhibitors have been demonstrated to promote NPC differentiation into glial lineage. Herein, to inhibit the downstream signaling activated by myelin associated inhibitors, cetuximab, an epidermal growth factor receptor (EGFR) neutralizing antibody, functionalized collagen scaffold has been developed as a vehicle for NPC implantation. It was found that collagen-cetuximab 1 μg scaffolds enhanced neuronal differentiation and inhibited astrocytic differentiation of NPCs exposed to myelin proteins significantly in vitro. To test the therapeutic effect in vivo, NPCs expressing green fluorescent protein (GFP)-embedded scaffolds have been implanted into the 4 mm-long hemisection lesion of rats. We found that the collagen-cetuximab 5 μg scaffolds induced neuronal differentiation and decreased astrocytic differentiation of NPCs, enhanced axon regeneration, and promoted functional recovery markedly. A well-functionalized scaffold was constructed to improve the recovery of SCI, which could promote the neuronal differentiation of neural progenitor cells in vivo.
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Affiliation(s)
- Xiaoran Li
- Division of Nanobiomedicine, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
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Ju P, Zhang S, Yeap Y, Feng Z. Induction of neuronal phenotypes from NG2+ glial progenitors by inhibiting epidermal growth factor receptor in mouse spinal cord injury. Glia 2012; 60:1801-14. [DOI: 10.1002/glia.22398] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2011] [Accepted: 07/05/2012] [Indexed: 12/20/2022]
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Qu WS, Tian DS, Guo ZB, Fang J, Zhang Q, Yu ZY, Xie MJ, Zhang HQ, Lü JG, Wang W. Inhibition of EGFR/MAPK signaling reduces microglial inflammatory response and the associated secondary damage in rats after spinal cord injury. J Neuroinflammation 2012; 9:178. [PMID: 22824323 PMCID: PMC3418570 DOI: 10.1186/1742-2094-9-178] [Citation(s) in RCA: 102] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Accepted: 07/02/2012] [Indexed: 02/08/2023] Open
Abstract
Background Emerging evidence indicates that reactive microglia-initiated inflammatory responses are responsible for secondary damage after primary traumatic spinal cord injury (SCI); epidermal growth factor receptor (EGFR) signaling may be involved in cell activation. In this report, we investigate the influence of EGFR signaling inhibition on microglia activation, proinflammatory cytokine production, and the neuronal microenvironment after SCI. Methods Lipopolysaccharide-treated primary microglia/BV2 line cells and SCI rats were used as model systems. Both C225 and AG1478 were used to inhibit EGFR signaling activation. Cell activation and EGFR phosphorylation were observed after fluorescent staining and western blot. Production of interleukin-1beta (IL-1β) and tumor necrosis factor alpha (TNFα) was tested by reverse transcription PCR and ELISA. Western blot was performed to semi-quantify the expression of EGFR/phospho-EGFR, and phosphorylation of Erk, JNK and p38 mitogen-activated protein kinases (MAPK). Wet-dry weight was compared to show tissue edema. Finally, axonal tracing and functional scoring were performed to show recovery of rats. Results EGFR phosphorylation was found to parallel microglia activation, while EGFR blockade inhibited activation-associated cell morphological changes and production of IL-1β and TNFα. EGFR blockade significantly downregulated the elevated MAPK activation after cell activation; selective MAPK inhibitors depressed production of cytokines to a certain degree, suggesting that MAPK mediates the depression of microglia activation brought about by EGFR inhibitors. Subsequently, seven-day continual infusion of C225 or AG1478 in rats: reduced the expression of phospho-EGFR, phosphorylation of Erk and p38 MAPK, and production of IL-1β and TNFα; lessened neuroinflammation-associated secondary damage, like microglia/astrocyte activation, tissue edema and glial scar/cavity formation; and enhanced axonal outgrowth and functional recovery. Conclusions These findings indicate that inhibition of EGFR/MAPK suppresses microglia activation and associated cytokine production; reduces neuroinflammation-associated secondary damage, thus provides neuroprotection to SCI rats, suggesting that EGFR may be a therapeutic target, and C225 and AG1478 have potential for use in SCI treatment.
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Affiliation(s)
- Wen-Sheng Qu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, China
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Karimi-Abdolrezaee S, Billakanti R. Reactive astrogliosis after spinal cord injury-beneficial and detrimental effects. Mol Neurobiol 2012; 46:251-64. [PMID: 22684804 DOI: 10.1007/s12035-012-8287-4] [Citation(s) in RCA: 254] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 05/29/2012] [Indexed: 11/29/2022]
Abstract
Reactive astrogliosis is a pathologic hallmark of spinal cord injury (SCI). It is characterised by profound morphological, molecular, and functional changes in astrocytes that occur within hours of SCI and evolves as time elapses after injury. Astrogliosis is a defense mechanism to minimize and repair the initial damage but eventually leads to some detrimental effects. Reactive astrocytes secrete a plethora of both growth promoting and inhibitory factors after SCI. However, the production of inhibitory components surpasses the growth stimulating factors, thus, causing inhibitory effects. In severe cases of injury, astrogliosis results in the formation of irreversible glial scarring that acts as regeneration barrier due to the expression of inhibitory components such as chondroitin sulfate proteoglycans. Scar formation was therefore recognized from a negative perspective for many years. Accumulating evidence from pharmacological and genetic studies now signifies the importance of astrogliosis and its timing for spinal cord repair. These studies have advanced our knowledge regarding signaling pathways and molecular mediators, which trigger and modulate reactive astrocytes and scar formation. In this review, we discuss the recent advances in this field. We also review therapeutic strategies that have been developed to target astrocytes reactivity and glial scaring in the environment of SCI. Astrocytes play pivotal roles in governing SCI mechanisms, and it is therefore crucial to understand how their activities can be targeted efficiently to harness their potential for repair and regeneration after SCI.
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Affiliation(s)
- Soheila Karimi-Abdolrezaee
- Regenerative Medicine Program, Departments of Physiology and Biochemistry and Medical Genetics, the Spinal Cord Research Center, University of Manitoba, Winnipeg, MB R3E 0J9, Canada.
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Transforming growth factor α transforms astrocytes to a growth-supportive phenotype after spinal cord injury. J Neurosci 2011; 31:15173-87. [PMID: 22016551 DOI: 10.1523/jneurosci.3441-11.2011] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Astrocytes are both detrimental and beneficial for repair and recovery after spinal cord injury (SCI). These dynamic cells are primary contributors to the growth-inhibitory glial scar, yet they are also neuroprotective and can form growth-supportive bridges on which axons traverse. We have shown that intrathecal administration of transforming growth factor α (TGFα) to the contused mouse spinal cord can enhance astrocyte infiltration and axonal growth within the injury site, but the mechanisms of these effects are not well understood. The present studies demonstrate that the epidermal growth factor receptor (EGFR) is upregulated primarily by astrocytes and glial progenitors early after SCI. TGFα directly activates the EGFR on these cells in vitro, inducing their proliferation, migration, and transformation to a phenotype that supports robust neurite outgrowth. Overexpression of TGFα in vivo by intraparenchymal adeno-associated virus injection adjacent to the injury site enhances cell proliferation, alters astrocyte distribution, and facilitates increased axonal penetration at the rostral lesion border. To determine whether endogenous EGFR activation is required after injury, SCI was also performed on Velvet (C57BL/6J-Egfr(Vel)/J) mice, a mutant strain with defective EGFR activity. The affected mice exhibited malformed glial borders, larger lesions, and impaired recovery of function, indicating that intrinsic EGFR activation is necessary for neuroprotection and normal glial scar formation after SCI. By further stimulating precursor proliferation and modifying glial activation to promote a growth-permissive environment, controlled stimulation of EGFR at the lesion border may be considered in the context of future strategies to enhance endogenous cellular repair after injury.
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Ferguson AR, Stück ED, Nielson JL. Syndromics: a bioinformatics approach for neurotrauma research. Transl Stroke Res 2011; 2:438-54. [PMID: 22207883 PMCID: PMC3236294 DOI: 10.1007/s12975-011-0121-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Revised: 10/14/2011] [Accepted: 10/18/2011] [Indexed: 12/25/2022]
Abstract
Substantial scientific progress has been made in the past 50 years in delineating many of the biological mechanisms involved in the primary and secondary injuries following trauma to the spinal cord and brain. These advances have highlighted numerous potential therapeutic approaches that may help restore function after injury. Despite these advances, bench-to-bedside translation has remained elusive. Translational testing of novel therapies requires standardized measures of function for comparison across different laboratories, paradigms, and species. Although numerous functional assessments have been developed in animal models, it remains unclear how to best integrate this information to describe the complete translational "syndrome" produced by neurotrauma. The present paper describes a multivariate statistical framework for integrating diverse neurotrauma data and reviews the few papers to date that have taken an information-intensive approach for basic neurotrauma research. We argue that these papers can be described as the seminal works of a new field that we call "syndromics", which aim to apply informatics tools to disease models to characterize the full set of mechanistic inter-relationships from multi-scale data. In the future, centralized databases of raw neurotrauma data will enable better syndromic approaches and aid future translational research, leading to more efficient testing regimens and more clinically relevant findings.
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Affiliation(s)
- Adam R. Ferguson
- Brain and Spinal Injury Center (BASIC), Department of Neurological Surgery, University of California, 1001 Potrero Avenue, Building 1, Room 101, San Francisco, CA 94110 USA
| | - Ellen D. Stück
- Brain and Spinal Injury Center (BASIC), Department of Neurological Surgery, University of California, 1001 Potrero Avenue, Building 1, Room 101, San Francisco, CA 94110 USA
| | - Jessica L. Nielson
- Brain and Spinal Injury Center (BASIC), Department of Neurological Surgery, University of California, 1001 Potrero Avenue, Building 1, Room 101, San Francisco, CA 94110 USA
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