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Li CP, Wu S, Sun YQ, Peng XQ, Gong M, Du HZ, Zhang J, Teng ZQ, Wang N, Liu CM. Lhx2 promotes axon regeneration of adult retinal ganglion cells and rescues neurodegeneration in mouse models of glaucoma. Cell Rep Med 2024; 5:101554. [PMID: 38729157 PMCID: PMC11148806 DOI: 10.1016/j.xcrm.2024.101554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 03/27/2024] [Accepted: 04/12/2024] [Indexed: 05/12/2024]
Abstract
The axons of retinal ganglion cells (RGCs) form the optic nerve, transmitting visual information from the eye to the brain. Damage or loss of RGCs and their axons is the leading cause of visual functional defects in traumatic injury and degenerative diseases such as glaucoma. However, there are no effective clinical treatments for nerve damage in these neurodegenerative diseases. Here, we report that LIM homeodomain transcription factor Lhx2 promotes RGC survival and axon regeneration in multiple animal models mimicking glaucoma disease. Furthermore, following N-methyl-D-aspartate (NMDA)-induced excitotoxicity damage of RGCs, Lhx2 mitigates the loss of visual signal transduction. Mechanistic analysis revealed that overexpression of Lhx2 supports axon regeneration by systematically regulating the transcription of regeneration-related genes and inhibiting transcription of Semaphorin 3C (Sema3C). Collectively, our studies identify a critical role of Lhx2 in promoting RGC survival and axon regeneration, providing a promising neural repair strategy for glaucomatous neurodegeneration.
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Affiliation(s)
- Chang-Ping Li
- Key Laboratory of Organ Regeneration and Reconstruction, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; Savaid Medical School, University of Chinese Academy of Sciences, Beijing 100049, China; Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, China; Beijing Institute for Stem Cell and Regenerative Medicine, Beijing 100101, China
| | - Shen Wu
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing 100730, China; Beijing Institute of Brain Disorders, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing 100069, China
| | - Yong-Quan Sun
- Key Laboratory of Organ Regeneration and Reconstruction, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; Savaid Medical School, University of Chinese Academy of Sciences, Beijing 100049, China; Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, China; Beijing Institute for Stem Cell and Regenerative Medicine, Beijing 100101, China
| | - Xue-Qi Peng
- Key Laboratory of Organ Regeneration and Reconstruction, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; Savaid Medical School, University of Chinese Academy of Sciences, Beijing 100049, China; Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, China; Beijing Institute for Stem Cell and Regenerative Medicine, Beijing 100101, China
| | - Maolei Gong
- Key Laboratory of Organ Regeneration and Reconstruction, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, China; Beijing Institute for Stem Cell and Regenerative Medicine, Beijing 100101, China
| | - Hong-Zhen Du
- Key Laboratory of Organ Regeneration and Reconstruction, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, China; Beijing Institute for Stem Cell and Regenerative Medicine, Beijing 100101, China
| | - Jingxue Zhang
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing 100730, China; Beijing Institute of Brain Disorders, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing 100069, China
| | - Zhao-Qian Teng
- Key Laboratory of Organ Regeneration and Reconstruction, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; Savaid Medical School, University of Chinese Academy of Sciences, Beijing 100049, China; Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, China; Beijing Institute for Stem Cell and Regenerative Medicine, Beijing 100101, China.
| | - Ningli Wang
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing 100730, China; Beijing Institute of Brain Disorders, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing 100069, China; Henan Academy of Innovations in Medical Science, Zhengzhou, Henan 450052, China.
| | - Chang-Mei Liu
- Key Laboratory of Organ Regeneration and Reconstruction, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; Savaid Medical School, University of Chinese Academy of Sciences, Beijing 100049, China; Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, China; Beijing Institute for Stem Cell and Regenerative Medicine, Beijing 100101, China.
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Abbaszadeh F, Jorjani M, Joghataei MT, Mehrabi S. Astaxanthin Modulates Autophagy, Apoptosis, and Neuronal Oxidative Stress in a Rat Model of Compression Spinal Cord Injury. Neurochem Res 2022; 47:2043-2051. [DOI: 10.1007/s11064-022-03593-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 03/28/2022] [Accepted: 03/28/2022] [Indexed: 10/18/2022]
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Ribas VT, Vahsen BF, Tatenhorst L, Estrada V, Dambeck V, Almeida RA, Bähr M, Michel U, Koch JC, Müller HW, Lingor P. AAV-mediated inhibition of ULK1 promotes axonal regeneration in the central nervous system in vitro and in vivo. Cell Death Dis 2021; 12:213. [PMID: 33637688 PMCID: PMC7910615 DOI: 10.1038/s41419-021-03503-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 01/12/2021] [Accepted: 01/15/2021] [Indexed: 01/31/2023]
Abstract
Axonal damage is an early step in traumatic and neurodegenerative disorders of the central nervous system (CNS). Damaged axons are not able to regenerate sufficiently in the adult mammalian CNS, leading to permanent neurological deficits. Recently, we showed that inhibition of the autophagic protein ULK1 promotes neuroprotection in different models of neurodegeneration. Moreover, we demonstrated previously that axonal protection improves regeneration of lesioned axons. However, whether axonal protection mediated by ULK1 inhibition could also improve axonal regeneration is unknown. Here, we used an adeno-associated viral (AAV) vector to express a dominant-negative form of ULK1 (AAV.ULK1.DN) and investigated its effects on axonal regeneration in the CNS. We show that AAV.ULK1.DN fosters axonal regeneration and enhances neurite outgrowth in vitro. In addition, AAV.ULK1.DN increases neuronal survival and enhances axonal regeneration after optic nerve lesion, and promotes long-term axonal protection after spinal cord injury (SCI) in vivo. Interestingly, AAV.ULK1.DN also increases serotonergic and dopaminergic axon sprouting after SCI. Mechanistically, AAV.ULK1.DN leads to increased ERK1 activation and reduced expression of RhoA and ROCK2. Our findings outline ULK1 as a key regulator of axonal degeneration and regeneration, and define ULK1 as a promising target to promote neuroprotection and regeneration in the CNS.
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Affiliation(s)
- Vinicius Toledo Ribas
- Department of Morphology, Universidade Federal de Minas Gerais, Avenida Presidente Antônio Carlos, 6627, Belo Horizonte, 31270-901, Brazil.
- Department of Neurology, University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany.
| | - Björn Friedhelm Vahsen
- Department of Neurology, University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
| | - Lars Tatenhorst
- Department of Neurology, University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
- Center for Biostructural Imaging of Neurodegeneration (BIN), University Medical Center Göttingen, Von-Siebold-Straße 3a, 37075, Göttingen, Germany
- DFG Cluster of Excellence Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
| | - Veronica Estrada
- Molecular Neurobiology Laboratory, Department of Neurology, Heinrich-Heine-University Medical Center Düsseldorf, Moorenstraße 5, 40225, Düsseldorf, Germany
| | - Vivian Dambeck
- Department of Neurology, University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
- Center for Biostructural Imaging of Neurodegeneration (BIN), University Medical Center Göttingen, Von-Siebold-Straße 3a, 37075, Göttingen, Germany
- DFG Cluster of Excellence Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
| | - Raquel Alves Almeida
- Department of Morphology, Universidade Federal de Minas Gerais, Avenida Presidente Antônio Carlos, 6627, Belo Horizonte, 31270-901, Brazil
| | - Mathias Bähr
- Department of Neurology, University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
- DFG Cluster of Excellence Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
| | - Uwe Michel
- Department of Neurology, University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
| | - Jan Christoph Koch
- Department of Neurology, University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
- DFG Cluster of Excellence Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
| | - Hans Werner Müller
- Molecular Neurobiology Laboratory, Department of Neurology, Heinrich-Heine-University Medical Center Düsseldorf, Moorenstraße 5, 40225, Düsseldorf, Germany
| | - Paul Lingor
- Department of Neurology, University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
- Center for Biostructural Imaging of Neurodegeneration (BIN), University Medical Center Göttingen, Von-Siebold-Straße 3a, 37075, Göttingen, Germany
- DFG Cluster of Excellence Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), University Medical Center Göttingen, Robert-Koch-Straße 40, 37075, Göttingen, Germany
- Department of Neurology, Rechts der Isar Hospital of the Technical University Munich, Ismaninger Straße 22, 81675, Munich, Germany
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Tang YJ, Li K, Yang CL, Huang K, Zhou J, Shi Y, Xie KG, Liu J. Bisperoxovanadium protects against spinal cord injury by regulating autophagy via activation of ERK1/2 signaling. DRUG DESIGN DEVELOPMENT AND THERAPY 2019; 13:513-521. [PMID: 30774313 PMCID: PMC6362923 DOI: 10.2147/dddt.s187878] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Background Spinal cord injury (SCI) is a disease of the central nervous system with few restorative treatments. Autophagy has been regarded as a promising therapeutic target for SCI. The inhibitor of phosphatase and tensin homolog deleted on chromosome ten (PTEN) bisperoxovanadium (bpV[pic]) had been claimed to provide a neuroprotective effect on SCI; but the underlying mechanism is still not fully understood. Materials and methods Acute SCI model were generated with SD Rats and were treated with control, acellular spinal cord scaffolds (ASC) obtained from normal rats, bpV(pic), and combined material of ASC and bpV(pic). We used BBB score to assess the motor function of the rats and the motor neurons were stained with Nissl staining. The expressions of the main autophagy markers LC3B, Beclin1 and P62, expressions of apoptosis makers Bax, Bcl2, PARP and Caspase 3 were detected with IF or Western Blot analysis. Results The bpV(pic) showed significant improvement in functional recovery by activating autophagy and accompanied by decreased neuronal apoptosis; combined ASC with bpV(pic) enhanced these effects. In addition, after treatment with ERK1/2 inhibitor SCH772984, we revealed that bpV(pic) promotes autophagy and inhibits apoptosis through activating ERK1/2 signaling after SCI. Conclusion These results illustrated that the bpV(pic) protects against SCI by regulating autophagy via activation of ERK1/2 signaling.
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Affiliation(s)
- Yu-Jin Tang
- Department of Orthopaedics, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, China,
| | - Kai Li
- Academy of Orthopedics, The Third Affiliated Hospital of Southern Medical University, Guangzhou, Guangdong, China
| | - Cheng-Liang Yang
- Department of Orthopaedics, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, China,
| | - Ke Huang
- Department of Orthopaedics, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, China,
| | - Jing Zhou
- Department of Anatomy, Youjiang Medical University for Nationalities, Baise, Guangxi, China
| | - Yu Shi
- Department of Orthopaedics, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, China,
| | - Ke-Gong Xie
- Department of Orthopaedics, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, China,
| | - Jia Liu
- Department of Orthopaedics, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, Guangxi, China,
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Theis T, Yoo M, Park CS, Chen J, Kügler S, Gibbs KM, Schachner M. Lentiviral Delivery of miR-133b Improves Functional Recovery After Spinal Cord Injury in Mice. Mol Neurobiol 2017; 54:4659-4671. [PMID: 27412702 DOI: 10.1007/s12035-016-0007-z] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 06/05/2016] [Indexed: 02/05/2023]
Abstract
Based on the observation that microRNA (miRNA) 133b enhances regeneration after spinal cord injury in the adult zebrafish, we investigated whether this miRNA would be beneficial in a mammalian system in vitro and in vivo. We found that infection of cultured neurons with miR-133b promotes neurite outgrowth in vitro on an inhibitory substrate consisting of mixed chondroitin sulfate proteoglycans, when compared to infection with green fluorescent protein (GFP) for control. In vivo, viral infection of the injured adult mouse spinal cord at the time of injury at and in the vicinity of the lesion site enhanced expression of miR-133b. Measurements of locomotor recovery by Basso Mouse Scale (BMS) showed improvement of recovery starting at 4 weeks after injury and virus injection. This improvement was associated with downregulation of the expression levels of Ras homolog gene family member A (RhoA), chondroitin sulfate proteoglycans, and microglia/macrophage marker in the spinal cord as assayed 6 weeks after injury. Potential inhibitory molecules carrying consensus sequences for binding of miR-133b were identified in silico and verified in a reporter assay in vitro showing reductions in expression of RhoA, xylosyltransferase 1 (Xylt1), ephrin receptor A7 (Epha7), and purinergic receptor P2X ligand-gated ion channel 4 (P2RX4). These results encourage targeting miR-133 for therapy.
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Affiliation(s)
- Thomas Theis
- Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ, 08554, USA
| | - Myung Yoo
- Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ, 08554, USA
| | - Christopher S Park
- Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ, 08554, USA
| | - Jian Chen
- Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ, 08554, USA
| | - Sebastian Kügler
- Department of Neurology, Center Nanoscale Microscopy and Physiology of the Brain, University Medicine, Göttingen, Germany
| | - Kurt M Gibbs
- Morehead State University, Morehead, KY, 40351, USA
| | - Melitta Schachner
- Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ, 08554, USA.
- Zentrum für Molekulare Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany.
- Center for Neuroscience, Shantou University Medical College, 22 Xin Ling Road, Shantou, Guangdong, 515041, China.
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Blits B, Boer GJ, Verhaagen J. Pharmacological, Cell, and Gene Therapy Strategies to Promote Spinal Cord Regeneration. Cell Transplant 2017. [DOI: 10.3727/000000002783985521] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In this review, recent studies using pharmacological treatment, cell transplantation, and gene therapy to promote regeneration of the injured spinal cord in animal models will be summarized. Pharmacological and cell transplantation treatments generally revealed some degree of effect on the regeneration of the injured ascending and descending tracts, but further improvements to achieve a more significant functional recovery are necessary. The use of gene therapy to promote repair of the injured nervous system is a relatively new concept. It is based on the development of methods for delivering therapeutic genes to neurons, glia cells, or nonneural cells. Direct in vivo gene transfer or gene transfer in combination with (neuro)transplantation (ex vivo gene transfer) appeared powerful strategies to promote neuronal survival and axonal regrowth following traumatic injury to the central nervous system. Recent advances in understanding the cellular and molecular mechanisms that govern neuronal survival and neurite outgrowth have enabled the design of experiments aimed at viral vector-mediated transfer of genes encoding neurotrophic factors, growth-associated proteins, cell adhesion molecules, and antiapoptotic genes. Central to the success of these approaches was the development of efficient, nontoxic vectors for gene delivery and the acquirement of the appropriate (genetically modified) cells for neurotransplantation. Direct gene transfer in the nervous system was first achieved with herpes viral and E1-deleted adenoviral vectors. Both vector systems are problematic in that these vectors elicit immunogenic and cytotoxic responses. Adeno-associated viral vectors and lentiviral vectors constitute improved gene delivery systems and are beginning to be applied in neuroregeneration research of the spinal cord. Ex vivo approaches were initially based on the implantation of genetically modified fibroblasts. More recently, transduced Schwann cells, genetically modified pieces of peripheral nerve, and olfactory ensheathing glia have been used as implants into the injured spinal cord.
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Affiliation(s)
- Bas Blits
- Graduate School Neurosciences Amsterdam, Netherlands Institute for Brain Research, Meibergdreef 33, 1105 AZ Amsterdam-ZO, The Netherlands
| | - Gerard J. Boer
- Graduate School Neurosciences Amsterdam, Netherlands Institute for Brain Research, Meibergdreef 33, 1105 AZ Amsterdam-ZO, The Netherlands
| | - Joost Verhaagen
- Graduate School Neurosciences Amsterdam, Netherlands Institute for Brain Research, Meibergdreef 33, 1105 AZ Amsterdam-ZO, The Netherlands
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Jadhav AD, Wei L, Shi P. Compartmentalized Platforms for Neuro-Pharmacological Research. Curr Neuropharmacol 2016; 14:72-86. [PMID: 26813122 PMCID: PMC4787287 DOI: 10.2174/1570159x13666150516000957] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Revised: 04/09/2015] [Accepted: 05/12/2015] [Indexed: 01/09/2023] Open
Abstract
Dissociated primary neuronal cell culture remains an indispensable approach for neurobiology research in order to investigate basic mechanisms underlying diverse neuronal functions, drug screening and pharmacological investigation. Compartmentalization, a widely adopted technique since its emergence in 1970s enables spatial segregation of neuronal segments and detailed investigation that is otherwise limited with traditional culture methods. Although these compartmental chambers (e.g. Campenot chamber) have been proven valuable for the investigation of Peripheral Nervous System (PNS) neurons and to some extent within Central Nervous System (CNS) neurons, their utility has remained limited given the arduous manufacturing process, incompatibility with high-resolution optical imaging and limited throughput. The development in the area of microfabrication and microfluidics has enabled creation of next generation compartmentalized devices that are cheap, easy to manufacture, require reduced sample volumes, enable precise control over the cellular microenvironment both spatially as well as temporally, and permit highthroughput testing. In this review we briefly evaluate the various compartmentalization tools used for neurobiological research, and highlight application of the emerging microfluidic platforms towards in vitro single cell neurobiology.
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Affiliation(s)
| | | | - Peng Shi
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR.
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XIA BIN, LIU HEYU, XIE JUANKE, WU RUI, LI YALI. Akt enhances nerve growth factor-induced axon growth via activating the Nrf2/ARE pathway. Int J Mol Med 2015; 36:1426-32. [DOI: 10.3892/ijmm.2015.2329] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Accepted: 08/20/2015] [Indexed: 11/06/2022] Open
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Therapeutical Strategies for Spinal Cord Injury and a Promising Autologous Astrocyte-Based Therapy Using Efficient Reprogramming Techniques. Mol Neurobiol 2015; 53:2826-2842. [DOI: 10.1007/s12035-015-9157-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 03/19/2015] [Indexed: 01/01/2023]
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10
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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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11
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Petrosyan TR, Gevorkyan OV, Chavushyan VA, Meliksetyan IB, Hovsepyan AS, Manvelyan LR. Effects of bacterial melanin on motor recovery and regeneration after unilateral destruction of Substantia Nigra pars compacta in rats. Neuropeptides 2014; 48:37-46. [PMID: 24176246 DOI: 10.1016/j.npep.2013.10.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 09/13/2013] [Accepted: 10/04/2013] [Indexed: 10/26/2022]
Abstract
We examined the potential neuroprotective action of bacterial melanin (BM) in rats after unilateral destruction of Substantia Nigra pars compacta (SNc) dopaminergic neurons. 24 rats were initially trained to an instrumental conditioned reflex (ICR) and then subjected to unilateral electrolytic destruction of SNc. Unilateral deficit in balancing hindlimb movements was observed in all rats after the destruction. On the next day after the destruction part of the animals (n=12) was intramuscularly injected with BM solution at the concentration 6 mg/ml (0.17 g/kg). The other 12 operated rats served as a control group. On the second day after the operation the testing of instrumental conditioned reflex was resumed in both groups. Comparison of recovery periods for the ICR in both groups showed that recovery of the reflex and balancing hindlimb movements in melanin treated rats took place in three postoperative testing days, whereas in control group the recovery was not complete after 23 testing days. Electrophysiological study was conducted in 12 intact rats to show the effects of BM on the activity of SNc neurons. The firing rate of neurons was significantly increased by the BM injection. Morpho-histochemical study of brain sections was conducted after the completion of behavioral experiments. In melanin injected rats the study revealed absence of destruction or electrode trace in Substantia Nigra pars compacta of melanin injected rats. BM stimulates regeneration and microcirculation in SNc. Increased electrical activity of SN neurons and regenerative efforts induced by BM accelerate motor recovery after unilateral SNc destruction.
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Affiliation(s)
- T R Petrosyan
- Department of Kinesiology, Armenian State Institute of Physical Education, Yerevan, Armenia.
| | - O V Gevorkyan
- Orbeli Institute of Physiology, NAS, Yerevan, Armenia
| | | | | | | | - L R Manvelyan
- Orbeli Institute of Physiology, NAS, Yerevan, Armenia
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Xu J, Lacoske MH, Theodorakis EA. Neurotrophic natural products: chemistry and biology. Angew Chem Int Ed Engl 2014; 53:956-87. [PMID: 24353244 PMCID: PMC3945720 DOI: 10.1002/anie.201302268] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2013] [Indexed: 12/12/2022]
Abstract
Neurodegenerative diseases and spinal cord injury affect approximately 50 million people worldwide, bringing the total healthcare cost to over 600 billion dollars per year. Nervous system growth factors, that is, neurotrophins, are a potential solution to these disorders, since they could promote nerve regeneration. An average of 500 publications per year attests to the significance of neurotrophins in biomedical sciences and underlines their potential for therapeutic applications. Nonetheless, the poor pharmacokinetic profile of neurotrophins severely restricts their clinical use. On the other hand, small molecules that modulate neurotrophic activity offer a promising therapeutic approach against neurological disorders. Nature has provided an impressive array of natural products that have potent neurotrophic activities. This Review highlights the current synthetic strategies toward these compounds and summarizes their ability to induce neuronal growth and rehabilitation. It is anticipated that neurotrophic natural products could be used not only as starting points in drug design but also as tools to study the next frontier in biomedical sciences: the brain activity map project.
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Affiliation(s)
- Jing Xu
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0358 (USA), Homepage: http://theodorakisgroup.ucsd.edu
| | - Michelle H. Lacoske
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0358 (USA), Homepage: http://theodorakisgroup.ucsd.edu
| | - Emmanuel A. Theodorakis
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0358 (USA), Homepage: http://theodorakisgroup.ucsd.edu
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Xu J, Lacoske MH, Theodorakis EA. Neurotrophe Naturstoffe - ihre Chemie und Biologie. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201302268] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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14
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Schulz F, Lutz D, Rusche N, Bastús NG, Stieben M, Höltig M, Grüner F, Weller H, Schachner M, Vossmeyer T, Loers G. Gold nanoparticles functionalized with a fragment of the neural cell adhesion molecule L1 stimulate L1-mediated functions. NANOSCALE 2013; 5:10605-10617. [PMID: 24056775 DOI: 10.1039/c3nr02707d] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The neural cell adhesion molecule L1 is involved in nervous system development and promotes regeneration in animal models of acute and chronic injury of the adult nervous system. To translate these conducive functions into therapeutic approaches, a 22-mer peptide that encompasses a minimal and functional L1 sequence of the third fibronectin type III domain of murine L1 was identified and conjugated to gold nanoparticles (AuNPs) to obtain constructs that interact homophilically with the extracellular domain of L1 and trigger the cognate beneficial L1-mediated functions. Covalent conjugation was achieved by reacting mixtures of two cysteine-terminated forms of this L1 peptide and thiolated poly(ethylene) glycol (PEG) ligands (~2.1 kDa) with citrate stabilized AuNPs of two different sizes (~14 and 40 nm in diameter). By varying the ratio of the L1 peptide-PEG mixtures, an optimized layer composition was achieved that resulted in the expected homophilic interaction of the AuNPs. These AuNPs were stable as tested over a time period of 30 days in artificial cerebrospinal fluid and interacted with the extracellular domain of L1 on neurons and Schwann cells, as could be shown by using cells from wild-type and L1-deficient mice. In vitro, the L1-derivatized particles promoted neurite outgrowth and survival of neurons from the central and peripheral nervous system and stimulated Schwann cell process formation and proliferation. These observations raise the hope that, in combination with other therapeutic approaches, L1 peptide-functionalized AuNPs may become a useful tool to ameliorate the deficits resulting from acute and chronic injuries of the mammalian nervous system.
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Affiliation(s)
- Florian Schulz
- Institut für Physikalische Chemie, Universität Hamburg, Grindelallee 117, 20146 Hamburg, Germany.
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15
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Martínez‐Ramos C, Vallés‐Lluch A, Verdugo JMG, Ribelles JLG, Barcia Albacar JA, Orts AB, Soria López JM, Pradas MM. Channeled scaffolds implanted in adult rat brain. J Biomed Mater Res A 2012; 100:3276-86. [DOI: 10.1002/jbm.a.34273] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 04/28/2012] [Accepted: 05/03/2012] [Indexed: 12/17/2022]
Affiliation(s)
- Cristina Martínez‐Ramos
- Centro de Biomateriales, Universidad Politécnica de Valencia, PO Box 22012, E‐46071 Valencia, Spain
| | - Ana Vallés‐Lluch
- Centro de Biomateriales, Universidad Politécnica de Valencia, PO Box 22012, E‐46071 Valencia, Spain
| | - José Manuel García Verdugo
- Instituto Cavanilles, Universidad de Valencia, Polígono La Coma, E‐46980 Valencia, Spain
- CIBER de Enfermedades Neurodegenerativas, Instituto Nacional de Salud Carlos III, Spain
| | - José Luis Gómez Ribelles
- Centro de Biomateriales, Universidad Politécnica de Valencia, PO Box 22012, E‐46071 Valencia, Spain
- CIBER de Bioingeniería, Biomateriales y Nanomedicina, Instituto Nacional de Salud Carlos III, Spain
| | | | - Amparo Baiget Orts
- Centro de Biomateriales, Universidad Politécnica de Valencia, PO Box 22012, E‐46071 Valencia, Spain
| | - José Miguel Soria López
- CIBER de Enfermedades Neurodegenerativas, Instituto Nacional de Salud Carlos III, Spain
- Facultad Ciencias de la Salud, Universidad CEU Cardenal Herrera, Avda Seminario 46113 Moncada, Valencia, Spain
| | - Manuel Monleón Pradas
- Centro de Biomateriales, Universidad Politécnica de Valencia, PO Box 22012, E‐46071 Valencia, Spain
- CIBER de Bioingeniería, Biomateriales y Nanomedicina, Instituto Nacional de Salud Carlos III, Spain
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16
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More SV, Koppula S, Kim BW, Choi DK. The role of bioactive compounds on the promotion of neurite outgrowth. Molecules 2012; 17:6728-53. [PMID: 22664464 PMCID: PMC6268652 DOI: 10.3390/molecules17066728] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 05/01/2012] [Accepted: 05/28/2012] [Indexed: 12/18/2022] Open
Abstract
Neurite loss is one of the cardinal features of neuronal injury. Apart from neuroprotection, reorganization of the lost neuronal network in the injured brain is necessary for the restoration of normal physiological functions. Neuritogenic activity of endogenous molecules in the brain such as nerve growth factor is well documented and supported by scientific studies which show innumerable compounds having neurite outgrowth activity from natural sources. Since the damaged brain lacks the reconstructive capacity, more efforts in research are focused on the identification of compounds that promote the reformation of neuronal networks. An abundancy of natural resources along with the corresponding activity profiles have shown promising results in the field of neuroscience. Recently, importance has also been placed on understanding neurite formation by natural products in relation to neuronal injury. Arrays of natural herbal products having plentiful active constituents have been found to enhance neurite outgrowth. They act synergistically with neurotrophic factors to promote neuritogenesis in the diseased brain. Therefore use of natural products for neuroregeneration provides new insights in drug development for treating neuronal injury. In this study, various compounds from natural sources with potential neurite outgrowth activity are reviewed in experimental models.
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Affiliation(s)
| | | | | | - Dong-Kug Choi
- Department of Biotechnology, Research Institute for Biomedical and Health Science, Konkuk University, Chungju 380-701, Korea
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17
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Neuroprotective action of bacterial melanin in rats after corticospinal tract lesions. PATHOPHYSIOLOGY 2012; 19:71-80. [DOI: 10.1016/j.pathophys.2011.12.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 11/21/2011] [Accepted: 12/06/2011] [Indexed: 11/22/2022] Open
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18
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Loverde JR, Ozoka VC, Aquino R, Lin L, Pfister BJ. Live imaging of axon stretch growth in embryonic and adult neurons. J Neurotrauma 2011; 28:2389-403. [PMID: 21663384 DOI: 10.1089/neu.2010.1598] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Strategies for nervous system repair arise from knowledge of growth mechanisms via a growth cone. The distinctive process of axon stretch growth is a robust, long-term growth that may reveal new pathways to accelerate nerve repair. Here, a live imaging bioreactor was engineered to closely explore cellular events initiated by applied tension. The stretch growth potential between adult and embryonic dorsal root ganglion (DRG) neurons was investigated, an important difference in nerve repair. Embryonic axons were capable of unidirectional stretch growth rates of 4?mm/d and reliably reached 4?cm in length within 2 weeks. Adult axons could only reach 2?mm/d and took over 3 weeks to reach 4?cm. Utilizing time-lapse imaging, we observed growth cone motility in coordination with stretch growth. Upon initiation of stretching, growth cones retracted. However, within 10?h of continuous stretching, growth cones extended at a rate of 0.2?mm/d opposite the direction of applied tension, contributing to overall axon elongation. We analyzed fast mitochondrial transport under increasing levels of strain to determine the effect of stretch on axonal transport. Transport began to diminish at 24% strain, and was almost completely absent at 39% strain. Surprisingly, axons recovered and were capable of subsequent stretch growth. When tension was completely released (?5% strain), stretch grown axons retracted at rates up to 6.1??m/sec and slowed as resting tension was restored. This ability to assess the process of axon stretch growth in real time will allow detailed study of how tension can be used to drive axonal growth and retraction.
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Affiliation(s)
- Joseph R Loverde
- Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, New Jersey 07102-1982, USA
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Zhang SX, Huang F, Gates M, Holmberg EG. Scar ablation combined with LP/OEC transplantation promotes anatomical recovery and P0-positive myelination in chronically contused spinal cord of rats. Brain Res 2011; 1399:1-14. [DOI: 10.1016/j.brainres.2011.05.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Revised: 04/30/2011] [Accepted: 05/02/2011] [Indexed: 01/27/2023]
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20
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Yu YM, Gibbs KM, Davila J, Campbell N, Sung S, Todorova TI, Otsuka S, Sabaawy HE, Hart RP, Schachner M. MicroRNA miR-133b is essential for functional recovery after spinal cord injury in adult zebrafish. Eur J Neurosci 2011; 33:1587-97. [PMID: 21447094 DOI: 10.1111/j.1460-9568.2011.07643.x] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
MicroRNAs (miRNAs) play important roles during development and also in adult organisms by regulating the expression of multiple target genes. Here, we studied the function of miR-133b during zebrafish spinal cord regeneration and show upregulation of miR-133b expression in regenerating neurons of the brainstem after transection of the spinal cord. miR-133b has been shown to promote tissue regeneration in other tissue, but its ability to do so in the nervous system has yet to be tested. Inhibition of miR-133b expression by antisense morpholino (MO) application resulted in impaired locomotor recovery and reduced regeneration of axons from neurons in the nucleus of the medial longitudinal fascicle, superior reticular formation and intermediate reticular formation. miR-133b targets the small GTPase RhoA, which is an inhibitor of axonal growth, as well as other neurite outgrowth-related molecules. Our results indicate that miR-133b is an important determinant in spinal cord regeneration of adult zebrafish through reduction in RhoA protein levels by direct interaction with its mRNA. While RhoA has been studied as a therapeutic target in spinal cord injury, this is the first demonstration of endogenous regulation of RhoA by a microRNA that is required for spinal cord regeneration in zebrafish. The ability of miR-133b to suppress molecules that inhibit axon regrowth may underlie the capacity for adult zebrafish to recover locomotor function after spinal cord injury.
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Affiliation(s)
- Young-Mi Yu
- W. M. Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
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21
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Chung BG, Choo J. Microfluidic gradient platforms for controlling cellular behavior. Electrophoresis 2010; 31:3014-27. [PMID: 20734372 DOI: 10.1002/elps.201000137] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Concentration gradients play an important role in controlling biological and pathological processes, such as metastasis, embryogenesis, axon guidance, and wound healing. Microfluidic devices fabricated by photo- and soft lithography techniques can manipulate the fluidic flow and diffusion profile to create biomolecular gradients in a temporal and spatial manner. Furthermore, microfluidic devices enable the control of cell-extracellular microenvironment interactions, including cell-cell, cell-matrix, and cell-soluble factor interaction. In this paper, we review the development of microfluidic-based gradient devices and highlight their biological applications.
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Affiliation(s)
- Bong Geun Chung
- Department of Bionano Engineering, Hanyang University, Ansan, Korea.
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22
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Beneficial effect of the traditional chinese drug shu-xue-tong on recovery of spinal cord injury in the rat. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2010; 2011. [PMID: 20953395 PMCID: PMC2952331 DOI: 10.1155/2011/862197] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/03/2009] [Revised: 04/20/2010] [Accepted: 06/30/2010] [Indexed: 11/17/2022]
Abstract
Shu-Xue-Tong (SXT) is a traditional Chinese drug widely used to ameliorate stagnation of blood flow, such as brain or myocardial infarction. Whether SXT may have therapeutic value for spinal cord injury (SCI), during which ischemia plays an important role in its pathology, remains to be elucidated. We hypothesized that SXT may promote SCI healing by improving spinal cord blood flow (SCBF), and a study was thus designed to explore this possibility. Twenty-five male Sprague-Dawley rats were used. SCI was induced by compression, and SXT was administrated 24 h postinjury for 14 successive days. The effects of SXT were assessed by means of laser-Doppler flowmetry, motor functional analysis (open-field walking and footprint analysis), and histological analysis (hematoxylin-eosin and thionin staining and NeuN immunohistochemistry). SXT significantly promoted SCBF of the contused spinal cord and enhanced the recovery of motor function. Histological analysis indicated that the lesion size was reduced, the pathological changes were ameliorated, and more neurons were preserved. Based on these results we conclude that SXT can effectively improve SCI.
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Ahmed Z, Read ML, Berry M, Logan A. Satellite glia not DRG neurons constitutively activate EGFR but EGFR inactivation is not correlated with axon regeneration. Neurobiol Dis 2010; 39:292-300. [DOI: 10.1016/j.nbd.2010.04.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Revised: 04/12/2010] [Accepted: 04/26/2010] [Indexed: 01/16/2023] Open
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Compartmental culture of embryonic stem cell-derived neurons in microfluidic devices for use in axonal biology. Biotechnol Lett 2010; 32:1063-70. [PMID: 20424889 DOI: 10.1007/s10529-010-0280-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Accepted: 04/13/2010] [Indexed: 10/19/2022]
Abstract
Axonal pathology has been clearly implicated in neurodegenerative diseases making the compartmental culture of neurons a useful research tool. Primary neurons have already been cultured in compartmental microfluidic devices but their derivation from an animal is a time-consuming and difficult work and has a limit in their sources. Embryonic stem cell (ESC)-derived neurons (ESC_Ns) overcome this limit, since ESCs can be renewed without limit and can be differentiated into ESC_Ns by robust and reproducible protocols. In this research, ESC_Ns were derived from mouse ESCs in compartmental microfluidic devices, and their axons were isolated from the somal cell bodies. Once embryoid bodies (EBs) were localized in the microfluidic culture chamber, ESC_Ns spread out from the EBs and occupied the cell culture chamber. Their axons traversed the microchannels and finally were isolated from the somata, providing an arrangement comparable to dissociated primary neurons. This ESC_N compartmental microfluidic culture system not only offers a substitute for the primary neuron counterpart system but also makes it possible to make comparisons between the two systems.
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Makwana M, Werner A, Acosta-Saltos A, Gonitel R, Pararajasingam A, Pararajasingham A, Ruff C, Rumajogee P, Cuthill D, Galiano M, Bohatschek M, Wallace AS, Anderson PN, Mayer U, Behrens A, Raivich G. Peripheral facial nerve axotomy in mice causes sprouting of motor axons into perineuronal central white matter: time course and molecular characterization. J Comp Neurol 2010; 518:699-721. [PMID: 20034058 PMCID: PMC4491910 DOI: 10.1002/cne.22240] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Generation of new axonal sprouts plays an important role in neural repair. In the current study, we examined the appearance, composition and effects of gene deletions on intrabrainstem sprouts following peripheral facial nerve axotomy. Axotomy was followed by the appearance of galanin(+) and calcitonin gene-related peptide (CGRP)(+) sprouts peaking at day 14, matching both large, neuropeptide(+) subpopulations of axotomized facial motoneurons, but with CGRP(+) sprouts considerably rarer. Strong immunoreactivity for vesicular acetylcholine transporter (VAChT) and retrogradely transported MiniRuby following its application on freshly cut proximal facial nerve stump confirmed their axotomized motoneuron origin; the sprouts expressed CD44 and alpha7beta1 integrin adhesion molecules and grew apparently unhindered along neighboring central white matter tracts. Quantification of the galanin(+) sprouts revealed a stronger response following cut compared with crush (day 7-14) as well as enhanced sprouting after recut (day 8 + 6 vs. 14; 14 + 8 vs. 22), arguing against delayed appearance of sprouting being the result of the initial phase of reinnervation. Sprouting was strongly diminished in brain Jun-deficient mice but enhanced in alpha7 null animals that showed apparently compensatory up-regulation in beta1, suggesting important regulatory roles for transcription factors and the sprout-associated adhesion molecules. Analysis of inflammatory stimuli revealed a 50% reduction 12-48 hours following systemic endotoxin associated with neural inflammation and a tendency toward more sprouts in TNFR1/2 null mutants (P = 10%) with a reduced inflammatory response, indicating detrimental effects of excessive inflammation. Moreover, the study points to the usefulness of the facial axotomy model in exploring physiological and molecular stimuli regulating central sprouting.
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Affiliation(s)
- Milan Makwana
- Department of Obstetrics and Gynaecology, EGA Institute for Women's Health, University College London, United Kingdom
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26
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Transplantation of a combination of autologous neural differentiated and undifferentiated mesenchymal stem cells into injured spinal cord of rats. Spinal Cord 2009; 48:457-63. [PMID: 20010910 DOI: 10.1038/sc.2009.153] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
STUDY DESIGN The use of stem cells for functional recovery after spinal cord injury. OBJECTIVE The aim of this study was to evaluate the effects of a combination of autologous undifferentiated and neural-induced bone marrow mesenchymal stem cells (MSCs) on behavioral improvement in rats after inducing spinal cord injury and comparing with transplantation of undifferentiated and neural-induced MSCs alone. SETTING The study was conducted at the department of Clinical Sciences, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran. METHODS The spinal cord was injured by contusion using a Fogarty embolectomy catheter at the T8-T9 level of the spinal cord, and autologous MSCs were transplanted into the center of the developing lesion cavity, 3 mm cranial and 3 mm caudal to the cavity, at 7 days after induction of spinal cord compression injury. RESULTS At 5 weeks after transplantation, the presence of transplanted cells was detected in the spinal cord parenchyma using immunohistochemistry analysis. In all treatment groups (differentiated, undifferentiated and mix), there was less cavitation than lesion sites in the control group. The Basso-Beattie-Bresnahan (BBB) score was significantly higher in rats transplanted with a combination of cells and in rats transplanted with neural-induced MSCs alone than in undifferentiated and control rats. CONCLUSION Pre-differentiation of MSCs to neuron-like cells has a very important role in achieving the best results for functional improvement.
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Vialle R, Lacroix C, Harding I, Loureiro MC, Tadié M. Motor and sensitive axonal regrowth after multiple intercosto-lumbar neurotizations in a sheep model. Spinal Cord 2009; 48:367-74. [DOI: 10.1038/sc.2009.144] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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28
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Chun YW, Webster TJ. The role of nanomedicine in growing tissues. Ann Biomed Eng 2009; 37:2034-47. [PMID: 19499340 DOI: 10.1007/s10439-009-9722-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Accepted: 05/20/2009] [Indexed: 10/20/2022]
Abstract
Nanomedicine (a division of nanotechnology) is an interdisciplinary research field incorporating biology, chemistry, engineering and medicine with the intention to improve disease prevention, diagnosis, and treatment. Specifically, there have been great strides made in using nanomedicine to enhance the functions of cells necessary to regenerate a diverse number of tissues (such as bone, blood vessels, the bladder, teeth, the nervous system, and the heart to name a few). Traditional (micron-structured or nano-smooth) implants suffer from: (i) infection, (ii) inflammation, and (iii) insufficient prolonged bonding between the implanted material and surrounding tissue. To date, such conventional implants have been improved by implementing nanotopographical features on their surfaces. In this review paper, the application of nanomaterials to regenerate numerous organs (including, as specific examples, bone, neural, and bladder tissues) will be presented with necessary future directions highlighted for the field of nanomedicine to progress.
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Affiliation(s)
- Young Wook Chun
- Division of Engineering, Department of Orthopedics, Brown University, Providence, RI 02912, USA
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29
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Hall ED, Traystman RJ. Role of animal studies in the design of clinical trials. FRONTIERS OF NEUROLOGY AND NEUROSCIENCE 2009; 25:10-33. [PMID: 19478492 DOI: 10.1159/000209470] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Rolls A, Shechter R, London A, Segev Y, Jacob-Hirsch J, Amariglio N, Rechavi G, Schwartz M. Two faces of chondroitin sulfate proteoglycan in spinal cord repair: a role in microglia/macrophage activation. PLoS Med 2008; 5:e171. [PMID: 18715114 PMCID: PMC2517615 DOI: 10.1371/journal.pmed.0050171] [Citation(s) in RCA: 202] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2007] [Accepted: 07/07/2008] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Chondroitin sulfate proteoglycan (CSPG) is a major component of the glial scar. It is considered to be a major obstacle for central nervous system (CNS) recovery after injury, especially in light of its well-known activity in limiting axonal growth. Therefore, its degradation has become a key therapeutic goal in the field of CNS regeneration. Yet, the abundant de novo synthesis of CSPG in response to CNS injury is puzzling. This apparent dichotomy led us to hypothesize that CSPG plays a beneficial role in the repair process, which might have been previously overlooked because of nonoptimal regulation of its levels. This hypothesis is tested in the present study. METHODS AND FINDINGS We inflicted spinal cord injury in adult mice and examined the effects of CSPG on the recovery process. We used xyloside to inhibit CSPG formation at different time points after the injury and analyzed the phenotype acquired by the microglia/macrophages in the lesion site. To distinguish between the resident microglia and infiltrating monocytes, we used chimeric mice whose bone marrow-derived myeloid cells expressed GFP. We found that CSPG plays a key role during the acute recovery stage after spinal cord injury in mice. Inhibition of CSPG synthesis immediately after injury impaired functional motor recovery and increased tissue loss. Using the chimeric mice we found that the immediate inhibition of CSPG production caused a dramatic effect on the spatial organization of the infiltrating myeloid cells around the lesion site, decreased insulin-like growth factor 1 (IGF-1) production by microglia/macrophages, and increased tumor necrosis factor alpha (TNF-alpha) levels. In contrast, delayed inhibition, allowing CSPG synthesis during the first 2 d following injury, with subsequent inhibition, improved recovery. Using in vitro studies, we showed that CSPG directly activated microglia/macrophages via the CD44 receptor and modulated neurotrophic factor secretion by these cells. CONCLUSIONS Our results show that CSPG plays a pivotal role in the repair of injured spinal cord and in the recovery of motor function during the acute phase after the injury; CSPG spatially and temporally controls activity of infiltrating blood-borne monocytes and resident microglia. The distinction made in this study between the beneficial role of CSPG during the acute stage and its deleterious effect at later stages emphasizes the need to retain the endogenous potential of this molecule in repair by controlling its levels at different stages of post-injury repair.
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Affiliation(s)
- Asya Rolls
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel
| | - Ravid Shechter
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel
| | - Anat London
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel
| | - Yifat Segev
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel
| | - Jasmin Jacob-Hirsch
- Cancer Research Center, Sheba Medical Center and Sackler School of Medicine Tel-Aviv University, Ramat Aviv, Israel
| | - Ninette Amariglio
- Cancer Research Center, Sheba Medical Center and Sackler School of Medicine Tel-Aviv University, Ramat Aviv, Israel
| | - Gidon Rechavi
- Cancer Research Center, Sheba Medical Center and Sackler School of Medicine Tel-Aviv University, Ramat Aviv, Israel
| | - Michal Schwartz
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel
- * To whom correspondence should be addressed. E-mail:
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Galoyan AA, Sarkissian DS, Chavushyan VA, Meliksetyan IB, Avakyan ZE, Sulkhanyan RM, Poghosyan MV, Avetisyan ZA. Studies of the protective effect of the hypothalamic peptide PRP-3 on spinal cord neurons at different periods after lateral hemisection. NEUROCHEM J+ 2007. [DOI: 10.1134/s1819712407020092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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32
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Fawcett JW. The Glial Response to Injury and Its Role in the Inhibition of CNS Repair. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2007; 557:11-24. [PMID: 16955702 DOI: 10.1007/0-387-30128-3_2] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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33
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Yarygin VN, Banin VV, Yarygin KN, Bryukhovetskii AS. Regeneration of the rat spinal cord after thoracic segmentectomy: Growth and restoration of nerve conductors. ACTA ACUST UNITED AC 2007; 37:97-105. [PMID: 17187199 DOI: 10.1007/s11055-007-0155-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2005] [Indexed: 10/23/2022]
Abstract
The results presented in our previous report (Morfologiya, 127, No. 2 (2005)) provided evidence that consolidation of the spinal cord (SC) after thoracic segmentectomy in rats occurs as a result of the formation of a connective tissue scar, which is quicker when the defect is filled with collagen gel. The present report describes analysis of semithin sections and transmission electron microscopy studies demonstrating that regenerating nerve conductors traverse connective tissue in structures whose organization is identical to that of peripheral nerves. In the zone of SC rarefaction caudal to the trauma site, myelination of growing axons is mediated by glial cells without the formation of nerve trunks. Large numbers of fine regenerating conductors were seen at the sites of degenerated myelin fibers in the fasciculi of the white matter in the lumbar segments of the SC.
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Affiliation(s)
- V N Yarygin
- Faculty of Medical Biology, Russian State Medical University, Moscow, Russia
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Zhang H, Hayashi T, Tsuru K, Deguchi K, Nagahara M, Hayakawa S, Nagai M, Kamiya T, Osaka A, Abe K. Vascular endothelial growth factor promotes brain tissue regeneration with a novel biomaterial polydimethylsiloxane-tetraethoxysilane. Brain Res 2006; 1132:29-35. [PMID: 17189618 DOI: 10.1016/j.brainres.2006.09.117] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2006] [Revised: 09/21/2006] [Accepted: 09/25/2006] [Indexed: 12/22/2022]
Abstract
In the brain after infarction or trauma, the tissue eventually becomes pannecrotic and forms a cavity. In such situations, a scaffold is necessary for the implanted or migrated cells to produce new tissue. In this present study, therefore, we attempted to restore brain tissue using a novel biomaterial, polydimethylsiloxane-tetraethoxysilane (PDMS-TEOS) hybrid with or without vascular endothelial growth factor (VEGF), which is crucial for new vessel formation. When PDMS-TEOS scaffold was implanted into the artificial brain defect, it remained at the implanted site and kept the integrity of the brain shape. At 30 days after the implantation, the marginal territory of PDMS-TEOS scaffold became occupied by newly formed tissue. Immunohistochemical analysis revealed that the new tissue was constituted by astrocytes and endothelial cells. Addition of VEGF increased the newly produced tissue volume, and the immunohistochemical analysis showed that the numbers of astrocytes and endothelial cells were increased. Double staining with proliferation maker Ki67 demonstrated that VEGF significantly increased newly formed astrocytes and endothelial cells, indicating that addition of VEGF accelerated tissue restoration and angiogenesis. These findings show that implantation of PDMS-TEOS scaffold with VEGF might be effective for treating old brain infarction or trauma.
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Affiliation(s)
- HanZhe Zhang
- Department of Neurology, Graduate School of Medicine, Dentistry and Pharmacy, Okayama University, 2-5-1 Shikata-cho, Okayama, 700-8558, Japan
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35
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Piotrowicz A, Shoichet MS. Nerve guidance channels as drug delivery vehicles. Biomaterials 2006; 27:2018-27. [PMID: 16239029 DOI: 10.1016/j.biomaterials.2005.09.042] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2005] [Accepted: 09/26/2005] [Indexed: 11/18/2022]
Abstract
Nerve guidance channels (NGCs) have been shown to facilitate regeneration after transection injury to the peripheral nerve or spinal cord. Various therapeutic molecules, including neurotrophic factors, have improved regeneration and functional recovery after injury when combined with NGCs; however, their impact has not been maximized partly due to the lack of an appropriate drug delivery system. To address this limitation, nerve growth factor (NGF) was incorporated into NGCs of poly(2-hydroxyethyl methacrylate-co-methyl methacrylate), P(HEMA-co-MMA). The NGCs were synthesized by a liquid-liquid centrifugal casting process and three different methods of protein incorporation were compared in terms of protein distribution and NGF release profile: (1) NGF was encapsulated (with BSA) in biodegradable poly(d,l-lactide-co-glycolide) 85/15 microspheres, which were combined with a PHEMA polymerization formulation and coated on the inside of pre-formed NGCs by a second liquid-liquid centrifugal casting technique; (2) pre-formed NGCs were imbibed with a solution of NGF/BSA and (3) NGF/BSA alone was combined with a PHEMA formulation and coated on the inside of pre-formed NGCs by a second liquid-liquid centrifugal casting technique. Using a fluorescently labelled model protein, the distribution of proteins in NGCs prepared with a coating of either protein-loaded microspheres or protein alone was found to be confined to the inner PHEMA layer. Sustained release of NGF was achieved from NGCs with either NGF-loaded microspheres or NGF alone incorporated into the inner layer, but not from channels imbibed with NGF. By day 28, NGCs with microspheres released a total of 220 pg NGF/cm of channel whereas those NGCs imbibed with NGF released 1040 pg/cm and those NGCs with NGF incorporated directly in a PHEMA layer released 8624 pg/cm. The release of NGF from NGCs with microspheres was limited by a slow-degrading microsphere formulation and by the maximum amount of microspheres that could be incorporated into the NGCs structure. Notwithstanding, the liquid-liquid centrifugal casting process is promising for localized and controlled release of multiple factors that are key to tissue regeneration.
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Affiliation(s)
- Alexandra Piotrowicz
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College St., Toronto, Ont., Canada
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Faria F. Lesões vértebro-medulares – A perspectiva da reabilitação. REVISTA PORTUGUESA DE PNEUMOLOGIA 2006; 12:S45-53. [PMID: 25976284 DOI: 10.1016/s0873-2159(15)30467-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Affiliation(s)
- Filipa Faria
- Assistente Hospitalar de Medicina Física e de Reabilitação, Mestre em Engenharia da Saúde pela Universidade Católica de Lisboa
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Pfister BJ, Iwata A, Taylor AG, Wolf JA, Meaney DF, Smith DH. Development of transplantable nervous tissue constructs comprised of stretch-grown axons. J Neurosci Methods 2005; 153:95-103. [PMID: 16337007 DOI: 10.1016/j.jneumeth.2005.10.012] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2005] [Revised: 09/21/2005] [Accepted: 10/13/2005] [Indexed: 11/20/2022]
Abstract
Pursuing a new approach to nervous system repair, fasciculated axon tracts grown in vitro were developed into nervous tissue constructs designed to span peripheral nerve or spinal cord lesions. We optimized the newfound process of extreme axon stretch growth to maximize the number and length of axon tracts, reach an unprecedented axon growth-rate of 1cm/day, and create 5cm long axon tracts in 8 days to serve as the core component of a living nervous tissue construct. Immunocytochemical analysis confirmed that elongating fibers were axons, and that all major cytoskeletal constituents were present across the stretch-growth regions. We formed a transplantable nervous tissue construct by encasing the elongated cells in an 80% collagen hydrogel, removing them from culture, and inserting them into a synthetic conduit. Alternatively, we induced axon stretch growth directly on a surgical membrane that could be removed from the elongation device, and formed into a cylindrical construct suitable for transplant. The ability to rapidly create living nervous tissue constructs that recapitulates the uniaxial orientations of the original nerve offers an unexplored and potentially complimentary direction in nerve repair. Ideally, bridging nerve damage with living axon tracts may serve to establish or promote new functional connections.
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Affiliation(s)
- Bryan J Pfister
- Department of Neurosurgery, Center for Brain Injury Repair, University of Pennsylvania, 3320 Smith Walk, 105 Hayden Hall, Philadelphia, PA 19104, USA.
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Hou S, Xu Q, Tian W, Cui F, Cai Q, Ma J, Lee IS. The repair of brain lesion by implantation of hyaluronic acid hydrogels modified with laminin. J Neurosci Methods 2005; 148:60-70. [PMID: 15978668 DOI: 10.1016/j.jneumeth.2005.04.016] [Citation(s) in RCA: 141] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2004] [Revised: 03/28/2005] [Accepted: 04/08/2005] [Indexed: 12/18/2022]
Abstract
The hyaluronic acid (HA) hydrogels modified with laminin were used for implantation in rat brain in present study, in order to investigate its effects in reparation of injury in the CNS. Cross-linked HA hydrogels were synthesized and their characteristics were analyzed. Laminin, an extracellular matrix protein, which participates in neuronal development and survival, was immobilized on the backbone of the hydrogels. Hydrogels unmodified and modified with laminin were implanted into cortical defects mechanically created in rats and their ability to improve tissue reconstruction was then evaluated. After 6 and 12 weeks of implantation, sections of brains were processed with Nissl and Glees staining for revealing neural cell bodies and fibers, with DAB histochemistry for detecting the blood vessels, as well as with immunocytochemistry for recognizing GFAP. The sections were also taken to SEM and TEM for ultrastructral examination. The results showed that the HA hydrogels synthesized had mechanical properties and rheological behavior similar to the brain tissue. After being implanted into the lesion of the cortex, the porous hydrogels created a scaffold, which could support cell infiltration and angiogenesis, and simultaneously inhibit the formation of glial scar. In addition, HA hydrogels modified with laminin could promote neurite extension. It seems possible that the tissue engineering technique may pave the way to repair injury in the CNS as suggested by the results in present study.
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Affiliation(s)
- Shaoping Hou
- Beijing Institute for Neuroscience, Beijing Center of Neural Regeneration and Repairing, Capital University of Medical Sciences, Beijing 100054, PR China
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Taylor AM, Blurton-Jones M, Rhee SW, Cribbs DH, Cotman CW, Jeon NL. A microfluidic culture platform for CNS axonal injury, regeneration and transport. Nat Methods 2005; 2:599-605. [PMID: 16094385 PMCID: PMC1558906 DOI: 10.1038/nmeth777] [Citation(s) in RCA: 804] [Impact Index Per Article: 42.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2005] [Accepted: 06/22/2005] [Indexed: 11/09/2022]
Abstract
Investigation of axonal biology in the central nervous system (CNS) is hindered by a lack of an appropriate in vitro method to probe axons independently from cell bodies. Here we describe a microfluidic culture platform that polarizes the growth of CNS axons into a fluidically isolated environment without the use of targeting neurotrophins. In addition to its compatibility with live cell imaging, the platform can be used to (i) isolate CNS axons without somata or dendrites, facilitating biochemical analyses of pure axonal fractions and (ii) localize physical and chemical treatments to axons or somata. We report the first evidence that presynaptic (Syp) but not postsynaptic (Camk2a) mRNA is localized to developing rat cortical and hippocampal axons. The platform also serves as a straightforward, reproducible method to model CNS axonal injury and regeneration. The results presented here demonstrate several experimental paradigms using the microfluidic platform, which can greatly facilitate future studies in axonal biology.
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Affiliation(s)
- Anne M Taylor
- Department of Biomedical Engineering, University of California, Irvine, 204 Rockwell Engineering, Irvine, California 92697, USA
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Galoyan AA, Sarkissian JS, Chavushyan VA, Sulkhanyan RM, Avakyan ZE, Avetisyan ZA, Grigorian YK, Abrahamyan DO. Neuroprotective action of hypothalamic peptide PRP-1 at various time survivals following spinal cord hemisection. Neurochem Res 2005; 30:507-25. [PMID: 16076021 DOI: 10.1007/s11064-005-2686-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The purpose of the present study was to evaluate the neuroprotective action of proline-rich peptide-1 (PRP-1) produced by hypothalamic nuclei cells (nuclei paraventricularis and supraopticus) following lateral hemisection of spinal cord (SC). The dynamics of rehabilitative shifts were investigated at various periods of postoperative survival (1-2, 3, and 4 weeks), both with administration of PRP-1 and without it (control). We registered evoked spike flow activity in both interneurons and motoneurons of the same segment of transected and symmetric intact sides of SC and below it on the stimulation of mixed (n. ischiadicus), flexor (n. gastrocnemius) and extensor (n. peroneus communis) nerves. In the control group (administration of 0.9% saline as placebo), no significant decrease of post-stimulus activity of neurons was observed on the transected side by the 2nd week. This activity strongly decreased by week 3 postaxotomy, with some increase on the intact side, possibly of compensatory origin. No shifts occurred by the 4th week. Regardless of the period of administration, PRP-1 increased neuronal activity on the transected side, with the same activation levels on both SC sides. These data were confirmed by histochemical investigation. PRP-1 administration, both daily and every other day, for a period of 2-3 weeks led to prevention of scar formation and promotion of the re-growth of white matter nerve fibers in the damaged area. It also resulted in prevention of neuroglial elements degeneration and reduction in gliosis expression in the lesion supporting neuronal survival. Thus, PRP-1 achieved protection against "tissue stress", which was also confirmed by the registration of activity on the level of transection and restoration of the motor activity on the injured side. The obtained data propose the possibility of PRP-1 application in clinical practice for prevention of neurodegeneration of traumatic origin.
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Affiliation(s)
- Armen A Galoyan
- Buniatian Institute of Biochemistry NAS RA, Yerevan, Republic of Armenia.
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Galoyan AA, Sarkissian JS, Sulkhanyan RM, Chavushyan VA, Avetisyan ZA, Avakyan ZE, Gevorgyan AJ, Abrahamyan DO, Grigorian YK. PRP-1 Protective Effect against Central and Peripheral Neurodegeneration following n. ischiadicus Transection. Neurochem Res 2005; 30:487-505. [PMID: 16076020 DOI: 10.1007/s11064-005-2685-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
We investigated the action of the new hypothalamic proline-rich peptide (PRP-1), normally produced by neurosecretory cells of hypothalamic nuclei (NPV and NSO), 3 and 4 weeks following rat sciatic nerve transection. The impulse activity flow of interneurons (IN) and motoneurons (MN) on stimulation of mixed (n. ischiadicus), flexor (n. gastrocnemius--G) and extensor (n. peroneus communis--P) nerves of both injured and symmetric intact sides of spinal cord (SC) was recorded in rats with daily administration of PRP-1 (for a period of 3 weeks) and without it (control). On the injured side of SC in control, there were no responses of IN and MN on ipsilateral G and P stimulation, while responses were elicited on contralateral nerve stimulation. The neuron responses on the intact side of SC were revealed in a reverse ratio. Thus, there were no effects upon stimulation of the injured nerve distal stump in the control because of the absence of fusion between transected nerve stumps. This was also testified by the atrophy of the distal stump and the absence of motor activity of the affected limb. In PRP-1-treated animals, the responses of SC IN and MN in postaxotomy 3 weeks on the injured side of SC at ipsilateral nerve stimulation and on the intact side at contralateral nerve stimulation were recorded because of the obvious fusion of the severed nerve stumps. The histochemical data confirmed the electrophysiological findings. Complete coalescence of transected fibers together with restoration of the motor activity of the affected limb provided evidence for reinnervation on the injured side. Thus, it may be concluded that PRP-1 promotes nerve regeneration and may be used clinically to improve the outcome of peripheral nerve primary repair.
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Affiliation(s)
- Armen A Galoyan
- Buniatian Institute of Biochemistry NAS RA, 5/1 Sevag str, 375014, Yerevan, Republic of Armenia.
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Ahmed Z, Dent RG, Suggate EL, Barrett LB, Seabright RJ, Berry M, Logan A. Disinhibition of neurotrophin-induced dorsal root ganglion cell neurite outgrowth on CNS myelin by siRNA-mediated knockdown of NgR, p75NTR and Rho-A. Mol Cell Neurosci 2005; 28:509-23. [PMID: 15737741 DOI: 10.1016/j.mcn.2004.11.002] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2004] [Revised: 10/20/2004] [Accepted: 11/01/2004] [Indexed: 12/12/2022] Open
Abstract
The presence of multiple axon growth inhibitors may partly explain why central nervous system axons are generally incapable of regenerating after injury. Using RNA interference (RNAi) in dorsal root ganglia neurons (DRGN), we demonstrate siRNA-mediated silencing of components of the inhibitory signalling cascade, including p75NTR, NgR and Rho-A mRNA, of 70%, 100% and 100% of the relevant protein, respectively, while changes in neither protein levels nor cellular immunoreactivity were detected using the relevant scrambled siRNA control sequences. Importantly, after 48 h in culture after siRNA-mediated knockdown of Rho-A, neurite outgrowth was enhanced by 30% compared to that after p75NTR and 50% after NgR silencing. By 3 days, a 5-, 3.5- and 6.5-fold increase in betaIII-tubulin protein levels were observed compared to controls without siRNA after knockdown of p75NTR, NgR and Rho-A, respectively. Together, these results suggest that Rho-A knockdown might be the most effective target for a disinhibition strategy to promote CNS axon regeneration in vivo.
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MESH Headings
- Animals
- Cells, Cultured
- Down-Regulation/drug effects
- Down-Regulation/physiology
- Feedback, Physiological/drug effects
- Feedback, Physiological/physiology
- GPI-Linked Proteins
- Ganglia, Spinal/drug effects
- Ganglia, Spinal/metabolism
- Ganglia, Spinal/ultrastructure
- Myelin Proteins/metabolism
- Myelin Proteins/pharmacology
- Nerve Growth Factors/pharmacology
- Nerve Growth Factors/physiology
- Nerve Regeneration/drug effects
- Nerve Regeneration/physiology
- Neurites/drug effects
- Neurites/metabolism
- Nogo Receptor 1
- RNA, Small Interfering/pharmacology
- Rats
- Rats, Sprague-Dawley
- Receptor, Nerve Growth Factor
- Receptors, Cell Surface
- Receptors, Nerve Growth Factor/genetics
- Receptors, Nerve Growth Factor/metabolism
- Receptors, Peptide/genetics
- Receptors, Peptide/metabolism
- Tubulin/metabolism
- Up-Regulation/drug effects
- Up-Regulation/physiology
- rhoA GTP-Binding Protein/genetics
- rhoA GTP-Binding Protein/metabolism
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Affiliation(s)
- Zubair Ahmed
- Molecular Neuroscience Group, Department of Medicine, University of Birmingham, 3rd Floor Wolfson Research Laboratories, Queen Elizabeth Medical Centre, Edgbaston, Birmingham B15 2TH, UK.
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Abstract
Basic science advances in spinal cord injury and regeneration research have led to a variety of novel experimental therapeutics designed to promote functionally effective axonal regrowth and sprouting. Among these interventions are cell-based approaches involving transplantation of neural and non-neural tissue elements that have potential for restoring damaged neural pathways or reconstructing intraspinal synaptic circuitries by either regeneration or neuronal/glial replacement. Notably, some of these strategies (e.g., grafts of peripheral nerve tissue, olfactory ensheathing glia, activated macrophages, marrow stromal cells, myelin-forming oligodendrocyte precursors or stem cells, and fetal spinal cord tissue) have already been translated to the clinical arena, whereas others have imminent likelihood of bench-to-bedside application. Although this progress has generated considerable enthusiasm about treating what once was thought to be a totally incurable condition, there are many issues to be considered relative to treatment safety and efficacy. The following review reflects on different experimental applications of intraspinal transplantation with consideration of the underlying pathological, pathophysiological, functional, and neuroplastic responses to spinal trauma that such treatments may target along with related issues of procedural and biological safety. The discussion then moves to an overview of ongoing and completed clinical trials to date. The pros and cons of these endeavors are considered, as well as what has been learned from them. Attention is primarily directed at preclinical animal modeling and the importance of patterning clinical trials, as much as possible, according to laboratory experiences.
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Affiliation(s)
- Paul J Reier
- College of Medicine and McKnight Brain Institute, University of Florida, Gainesville, Florida 32610, USA.
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44
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Cellular transplantation strategies for spinal cord injury and translational neurobiology. Neurotherapeutics 2004. [DOI: 10.1007/bf03206629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Kapur TA, Shoichet MS. Immobilized concentration gradients of nerve growth factor guide neurite outgrowth. J Biomed Mater Res A 2004; 68:235-43. [PMID: 14704965 DOI: 10.1002/jbm.a.10168] [Citation(s) in RCA: 178] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Axons are guided to their targets by a combination of haptotactic and chemotactic cues. We previously demonstrated that soluble neurotrophic factor concentration gradients guide axons in a model system. In an attempt to translate this model system to a device for implantation, our goal was to immobilize a stable neurotrophic concentration gradient for axonal (or neurite) guidance. Nerve growth factor (NGF) was immobilized within poly(2-hydroxyethylmethacrylate) [p(HEMA)] microporous gels using a gradient maker. The NGF was stably immobilized, with only approximately 0.05% of the amount originally incorporated into the gel released over an 8-day period. Immobilized NGF was bioactive: the percent of PC12 cells extending neurites on NGF-immobilized p(HEMA) gels was 16 +/- 2%, which was statistically the same as those exposed to soluble NGF (22 +/- 6%). We were able to predict and reproducibly create stable NGF concentration gradients in the gel. At an NGF concentration gradient of 357 ng/mL/mm, PC12 cell neurites were guided up the gradient. The facile, flexible, and reproducible nature of this method allowed us to translate soluble growth factor gradient models to stable growth factor gradient devices that may ultimately enhance axonal guidance and regeneration in vivo.
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Affiliation(s)
- Terri Adams Kapur
- University of Toronto, Department of Chemical Engineering and Applied Chemistry, 200 College Street, Toronto ON Canada M5S 3E5
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Abrahamyan SS, Sarkissian JS, Meliksetyan IB, Galoyan AA. Survival of trauma-injured neurons in rat brain by treatment with proline-rich peptide (PRP-1): an immunohistochemical study. Neurochem Res 2004; 29:695-708. [PMID: 15098931 DOI: 10.1023/b:nere.0000018840.19073.0b] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The objective of this immunohistochemical research was to reveal the distribution of a proline-rich peptide-1 (PRP-1) in various brain structures of intact and trauma-injured rats and to identify the mechanisms of promotion of neuronal recovery processes following PRP-1 treatment. PRP-1, produced by bovine hypothalamic magnocellular cells and consisting of 15 amino acid residues, is a fragment of neurophysin vasopressin associated glycoprotein isolated from bovine neurohypophysis neurosecretory granules. PRP-1-immunoreactivity (PRP-1-IR) was detected in the brain of intact rats in the neurons of paraventricular (PVN) and supraoptic (SON) nuclei in the hypothalamus, in almost all cell groups in the medulla oblongata, in Purkinje and some cerebellar nuclei cells, and in nerve fibers. At 3 weeks after hemisection of the spinal cord (SC) an asymmetry of PRP-1 localization in the PVN and SON was observed: no PRP-1-IR was exhibited at the affected sides of both nuclei. Daily intramuscular administration of PRP-1 for 3 weeks significantly increased the number of PRP-1-immunoreactive (PRP-1-Ir) varicose nerve fibers, and cells in PVN and SON and in cell groups of the limbic system and brain stem. Tanycytes in the median eminence and covering ependyma also demonstrated strong PRP-1-IR. PRP-1 treatment also activated neuropeptide Y-IR (NPY-IR) in nerve fibers and immunophilin fragment-IR (IphF-IR) in lymphocytes and nerve cells. A strong increase of PRP-1-IR was observed in the PVN and SON of SC-injured rats following the treatment with another PRP (PRP-3). Preliminary physiological data demonstrate that PRP-3 is more "aggressive" in the recovery processes than PRP-1. Based on the findings regarding PRP action on neurons survival, axons regeneration, and the number of IphF-Ir lymphocytes and NPY-Ir nerve fibers, PRP is suggested to act as a neuroprotector, functioning as a putative neurotransmitter and immunomodulator.
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47
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Barnett SC, Chang L. Olfactory ensheathing cells and CNS repair: going solo or in need of a friend? Trends Neurosci 2004; 27:54-60. [PMID: 14698611 DOI: 10.1016/j.tins.2003.10.011] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Susan C Barnett
- Division of Clinical Neuroscience, University of Glasgow, Beatson Laboratories, Garscube Estate, Switchback Road, Glasgow G61 1BD, Scotland, UK.
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48
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Shaw D, Shoichet MS. Toward spinal cord injury repair strategies: peptide surface modification of expanded poly(tetrafluoroethylene) fibers for guided neurite outgrowth in vitro. J Craniofac Surg 2003; 14:308-16. [PMID: 12826801 DOI: 10.1097/00001665-200305000-00008] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Expanded poly(tetrafluoroethylene) fibers were surface modified using an ultraviolet-activated mercury/ammonia reaction to yield amine-functional groups for the coupling of laminin-derived cell adhesive peptides CYIGSR, CDPGYIGSR, CIKVAV, and CQAASIKVAV. Surface elemental composition, determined by X-ray photoelectron spectroscopy, and radiolabeling data indicated that the amount of peptide introduced was approximately equivalent regardless of peptide type, yet mixed peptide surfaces had approximately 60% YIGSR and 40% IKVAV. The peptide-modified surfaces were compared in terms of the response of dorsal root ganglia with neurite length and number of cells attached to each fiber measured. All peptide-functionalized surfaces had a greater cellular response than the aminated ePTFE and ePTFE controls. Surfaces modified with extended peptide sequences CDPGYIGSR and CQAASIKVAV demonstrated a greater cellular response than those modified with the shorter peptide sequences CYIGSR and CIKVAV, respectively, likely because the extended peptides more closely mimic the three-dimensional conformation that the peptides maintain in laminin. Differences in neurite extension were evident among the peptide-functionalized surfaces, with the longest neurites observed on surfaces modified with both CQAASIKVAV and CDPGYIGSR. The "guidance capacity" of the fibers as a function of fiber diameter was investigated in terms of length and directionality of neurite outgrowth. As fiber diameter decreased (from 100+ to 10 microm), the neurites tended to grow to a greater degree down the length of the fiber. The thinnest fibers (with diameters <20 microm) extended shorter neurites than the fibers with a wider diameter. Combining neurite length with guidance indicated that of the fiber diameters investigated, the optimal fiber diameter for neurite guidance was between 30 and 50 microm.
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Affiliation(s)
- Derek Shaw
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, 4 Taddle Creek Road, Toronto, Ontario M5S 3G9, Canada
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49
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Borisoff JF, Chan CCM, Hiebert GW, Oschipok L, Robertson GS, Zamboni R, Steeves JD, Tetzlaff W. Suppression of Rho-kinase activity promotes axonal growth on inhibitory CNS substrates. Mol Cell Neurosci 2003; 22:405-16. [PMID: 12691741 DOI: 10.1016/s1044-7431(02)00032-5] [Citation(s) in RCA: 169] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
Several molecules inhibit axonal growth cones and may account for the failure of central nervous system regeneration, including myelin proteins and various chondroitan sulfate proteoglycans expressed at the site of injury. Axonal growth inhibition by myelin and chondroitan sulfate proteoglycans may in part be controlled by Rho-GTPase, which mediates growth cone collapse. Here, we tested in vitro whether pharmacological inhibition of a major downstream effector of Rho, Rho-kinase, promotes axonal outgrowth from dorsal root ganglia grown on aggrecan. Aggrecan substrates stimulated Rho activity and were inhibitory to axonal growth. Y-27632 treatment promoted the growth of axons by 5- to 10-fold and induced "steamlined" growth cones with longer filopodia and smaller lamellipodia. Interestingly, more actin bundles reminiscent of stress fibers in the central domain of the growth cone were observed when grown on aggrecan compared to laminin. In addition, Y-27632 significantly promoted axonal growth on both myelin and adult rat spinal cord cryosections. Our data suggest that suppression of Rho-kinase activity may enhance axonal regeneration in the central nervous system.
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Affiliation(s)
- Jaimie F Borisoff
- CORD (Collaboration on Repair Discoveries), University of British Columbia, 6270 University Blvd., V6T 1Z4, Vancouver, British Columbia, Canada
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50
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Santos-Benito FF, Ramón-Cueto A. Olfactory ensheathing glia transplantation: a therapy to promote repair in the mammalian central nervous system. ANATOMICAL RECORD. PART B, NEW ANATOMIST 2003; 271:77-85. [PMID: 12619089 DOI: 10.1002/ar.b.10015] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A therapy to treat injuries to the central nervous system (CNS) is, to date, a major clinical challenge. The devastating functional consequences they cause in human patients have encouraged many scientists to search, in animal models, for a repair strategy that could, in the future, be applied to humans. However, although several experimental approaches have obtained some degree of success, very few have been translated into clinical trials. Traumatic and demyelinating lesions of the spinal cord have attracted several groups with the same aim: to find a way to promote axonal regeneration, remyelination, and functional recovery, by using a simple, safe, effective, and viable procedure. During the past decade, olfactory ensheathing glia (OEG) transplantation has emerged as a very promising experimental therapy to promote repair of spinal cords, after different types of injuries. Transplants of these cells promoted axonal regeneration and functional recovery after partial and complete spinal cord lesions. Moreover, olfactory ensheathing glia were able to form myelin sheaths around demyelinated axons. In this article, we review these recent advances and discuss to what extent olfactory ensheathing glia transplantation might have a future as a therapy for different spinal cord affections in humans.
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