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Kerzonkuf M, Verneuil J, Brocard C, Dingu N, Trouplin V, Ramirez Franco JJ, Bartoli M, Brocard F, Bras H. Knockdown of calpain1 in lumbar motoneurons reduces spasticity after spinal cord injury in adult rats. Mol Ther 2024; 32:1096-1109. [PMID: 38291756 PMCID: PMC11163198 DOI: 10.1016/j.ymthe.2024.01.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 12/23/2023] [Accepted: 01/23/2024] [Indexed: 02/01/2024] Open
Abstract
Spasticity, affecting ∼75% of patients with spinal cord injury (SCI), leads to hyperreflexia, muscle spasms, and cocontractions of antagonist muscles, greatly affecting their quality of life. Spasticity primarily stems from the hyperexcitability of motoneurons below the lesion, driven by an upregulation of the persistent sodium current and a downregulation of chloride extrusion. This imbalance results from the post-SCI activation of calpain1, which cleaves Nav1.6 channels and KCC2 cotransporters. Our study was focused on mitigating spasticity by specifically targeting calpain1 in spinal motoneurons. We successfully transduced lumbar motoneurons in adult rats with SCI using intrathecal administration of adeno-associated virus vector serotype 6, carrying a shRNA sequence against calpain1. This approach significantly reduced calpain1 expression in transduced motoneurons, leading to a noticeable decrease in spasticity symptoms, including hyperreflexia, muscle spasms, and cocontractions in hindlimb muscles, which are particularly evident in the second month post-SCI. In addition, this decrease, which prevented the escalation of spasticity to a severe grade, paralleled the restoration of KCC2 levels in transduced motoneurons, suggesting a reduced proteolytic activity of calpain1. These findings demonstrate that inhibiting calpain1 in motoneurons is a promising strategy for alleviating spasticity in SCI patients.
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Affiliation(s)
- Marjorie Kerzonkuf
- Institut des Neurosciences de la Timone (UMR7289), Aix-Marseille Université and CNRS, Marseille, France
| | - Jérémy Verneuil
- Institut des Neurosciences de la Timone (UMR7289), Aix-Marseille Université and CNRS, Marseille, France
| | - Cécile Brocard
- Institut des Neurosciences de la Timone (UMR7289), Aix-Marseille Université and CNRS, Marseille, France
| | - Nejada Dingu
- Institut des Neurosciences de la Timone (UMR7289), Aix-Marseille Université and CNRS, Marseille, France
| | - Virginie Trouplin
- Institut des Neurosciences de la Timone (UMR7289), Aix-Marseille Université and CNRS, Marseille, France
| | - Jose Jorge Ramirez Franco
- Institut des Neurosciences de la Timone (UMR7289), Aix-Marseille Université and CNRS, Marseille, France
| | - Marc Bartoli
- Institut Marseille Maladies Rares (MarMaRa), Aix-Marseille Université and INSERM, Marseille, France
| | - Frédéric Brocard
- Institut des Neurosciences de la Timone (UMR7289), Aix-Marseille Université and CNRS, Marseille, France.
| | - Hélène Bras
- Institut des Neurosciences de la Timone (UMR7289), Aix-Marseille Université and CNRS, Marseille, France.
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Shan S, Liu Z, Li L, Zhang C, Kou R, Song F. Calpain-mediated cleavage of mitochondrial fusion/fission proteins in acetaminophen-induced mice liver injury. Hum Exp Toxicol 2022; 41:9603271221108321. [PMID: 35713544 DOI: 10.1177/09603271221108321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Mitochondrial dysfunction was considered to be a critical event in acetaminophen (APAP) -induced hepatotoxicity. Recent studies suggest that abnormal mitochondrial dynamics contributes to mitochondrial dysfunction in APAP-induced liver injury, yet the underlying mechanisms responsible for deregulated mitochondrial dynamics remains elusive. In this study, C57BL/6 mice were used to establish a model of acute liver injury via intraperitoneal (i.p.) injection with overdose of APAP. Furthermore, calpain intervention experiments were achieved by the inhibitors ALLN or calpeptin. The activity of serum enzymes and pathological changes of APAP-treated mice were evaluated, and the critical molecules in mitochondrial dynamics and calpain degradative pathway were determined by electron microscopy, immunoblot and calpain activity kit. The results demonstrated that APAP overdose resulted in a severe liver injury, mitochondrial damage and an obvious cleavage of fusion/fission proteins. Meanwhile, the activation of calpain degradative machinery in liver were observed following APAP. By contrast, pretreatment of calpain inhibitors significantly inhibited the activation of calpains. Our further investigation found that ALLN or calpeptin administration significantly suppresses the changes of mitochondrial dynamics in APAP-treated mice and finally protected against APAP-induced hepatoxicity. Overall, these results suggest that calpain-mediated cleavage of mitochondrial dynamics proteins was involved in the pathogenic process of mitochondrial dysfunction and thus present a potential molecular coupling APAP-induced hepatotoxicity.
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Affiliation(s)
- Shulin Shan
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, 12589Shandong University, Jinan, China
| | - Zhaoxiong Liu
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, 12589Shandong University, Jinan, China
| | - Linlin Li
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, 12589Shandong University, Jinan, China
| | - Cuiqin Zhang
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, 12589Shandong University, Jinan, China
| | - Ruirui Kou
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, 12589Shandong University, Jinan, China
| | - Fuyong Song
- Department of Toxicology and Nutrition, School of Public Health, Cheeloo College of Medicine, 12589Shandong University, Jinan, China
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Involvement of the miR-137-3p/CAPN-2 Interaction in Ischemia-Reperfusion-Induced Neuronal Apoptosis through Modulation of p35 Cleavage and Subsequent Caspase-8 Overactivation. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2020; 2020:2616871. [PMID: 33456665 PMCID: PMC7787780 DOI: 10.1155/2020/2616871] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 11/20/2020] [Accepted: 11/26/2020] [Indexed: 12/13/2022]
Abstract
Background Neuron survival after ischemia-reperfusion (IR) injury is the primary determinant of motor function prognosis. MicroRNA- (miR-) based gene therapy has gained attention recently. Our previous work explored the mechanisms by which miR-137-3p modulates neuronal apoptosis in both in vivo and in vitro IR models. Methods IR-induced motor dysfunction and spinal calpain (CAPN) subtype expression and subcellular localization were detected within 12 h post IR. Dysregulated miRs, including miR-137-3p, were identified by miR microarray analysis and confirmed by PCR. A luciferase assay confirmed CAPN-2 as a corresponding target of miR-137-3p, and their modulation of motor function was evaluated by intrathecal injection with synthetic miRs. CAPN-2 activity was measured by the intracellular Ca2+ concentration and mean fluorescence intensity in vitro. Neuronal apoptosis was detected by flow cytometry and TUNEL assay. The activities of p35, p25, Cdk5, and caspase-8 were evaluated by ELISA and Western blot after transfection with specific inhibitors and miRs. Results The IR-induced motor dysfunction time course was closely associated with upregulated expression of the CAPN-2 protein, which was mainly localized in neurons. The miR-137-3p/CAPN-2 interaction was confirmed by luciferase assay. The miR-137-3p mimic significantly improved IR-induced motor dysfunction and decreased CAPN-2 expression, even in combination with recombinant rat calpain-2 (rr-CALP2) injection, whereas the miR-137-3p inhibitor reversed these effects. Similar changes in the intracellular Ca2+ concentration, CAPN-2 expression, and CAPN-2 activity were observed when cells were exposed to oxygen-glucose deprivation and reperfusion (OGD/R) and transfected with synthetic miRs in vitro. Moreover, double fluorescence revealed identical neuronal localization of CAPN-2, p35, p25, and caspase-8. The decrease in CAPN-2 expression and activity was accompanied by the opposite changes in p35 activity and protein expression in cells transfected with the miR-137-3p mimic, roscovitine (a Cdk5 inhibitor), or Z-IETD-FMK (a caspase-8 inhibitor). Correspondingly, the abovementioned treatments resulted in a higher neuron survival rate than that of untreated neurons, as indicated by decreases in the apoptotic cell percentage and p25, Cdk5, caspase-8, and caspase-3 protein expression. Conclusions The miR-137-3p/CAPN-2 interaction modulates neuronal apoptosis during IR injury, possibly by inhibiting CAPN-2, which leads to p35 cleavage and inhibition of subsequent p25/Cdk5 and caspase-8 overactivation.
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Nakhjiri E, Vafaee MS, Hojjati SMM, Shahabi P, Shahpasand K. Tau Pathology Triggered by Spinal Cord Injury Can Play a Critical Role in the Neurotrauma Development. Mol Neurobiol 2020; 57:4845-4855. [PMID: 32808121 DOI: 10.1007/s12035-020-02061-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 08/07/2020] [Indexed: 02/08/2023]
Abstract
Traumatic spinal cord injury (SCI) can result in substantial neurological impairment along with significant emotional and psychological distress. It is clear that there is profound neurodegeneration upon SCI, gradually spread to other spinal cord regions and brain areas. Despite extensive considerations, it remains uncertain how pathogenicity diffuses in the cord. It has been reported that tau protein abnormal hyperphosphorylation plays a central role in neurodegeneration triggered by traumatic brain injury (TBI). Tau is a microtubule-associated protein, heavily implicated in neurodegenerative diseases. Importantly, tau pathology spreads in a traumatic brain in a timely manner. In particular, we have recently demonstrated that phosphorylated tau at Thr231 exists in two distinct cis and trans conformations, in which that cis P-tau is extremely neurotoxic, has a prion nature, and spreads to various brain areas and cerebrospinal fluid (CSF) upon trauma. On the other hand, tau pathology, in particular hyperphosphorylation at Thr231, has been observed upon SCI. Taken these together, we conclude that cis pT231-tau may accumulate and spread in the spinal cord as well as CSF and diffuse tau pathology in the central nervous system (CNS). Moreover, antibody against cis P-tau can target intracellular cis P-tau and protect pathology spreading. Thus, considering cis P-tau as a driver of tau pathology and neurodegeneration upon SCI would open new windows toward understanding the disease development and early biomarkers. Furthermore, it would help us develop effective therapies for SCI patients.
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Affiliation(s)
- Elnaz Nakhjiri
- Neurosciences Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Manuchehr S Vafaee
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark
| | | | - Parviz Shahabi
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Koorosh Shahpasand
- Department of Brain and Cognitive Sciences, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran.
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Protein Degradome of Spinal Cord Injury: Biomarkers and Potential Therapeutic Targets. Mol Neurobiol 2020; 57:2702-2726. [PMID: 32328876 DOI: 10.1007/s12035-020-01916-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 03/31/2020] [Indexed: 12/13/2022]
Abstract
Degradomics is a proteomics sub-discipline whose goal is to identify and characterize protease-substrate repertoires. With the aim of deciphering and characterizing key signature breakdown products, degradomics emerged to define encryptic biomarker neoproteins specific to certain disease processes. Remarkable improvements in structural and analytical experimental methodologies as evident in research investigating cellular behavior in neuroscience and cancer have allowed the identification of specific degradomes, increasing our knowledge about proteases and their regulators and substrates along with their implications in health and disease. A physiologic balance between protein synthesis and degradation is sought with the activation of proteolytic enzymes such as calpains, caspases, cathepsins, and matrix metalloproteinases. Proteolysis is essential for development, growth, and regeneration; however, inappropriate and uncontrolled activation of the proteolytic system renders the diseased tissue susceptible to further neurotoxic processes. In this article, we aim to review the protease-substrate repertoires as well as emerging therapeutic interventions in spinal cord injury at the degradomic level. Several protease substrates and their breakdown products, essential for the neuronal structural integrity and functional capacity, have been characterized in neurotrauma including cytoskeletal proteins, neuronal extracellular matrix glycoproteins, cell junction proteins, and ion channels. Therefore, targeting exaggerated protease activity provides a potentially effective therapeutic approach in the management of protease-mediated neurotoxicity in reducing the extent of damage secondary to spinal cord injury.
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Tamtaji OR, Mirhosseini N, Reiter RJ, Azami A, Asemi Z. Melatonin, a calpain inhibitor in the central nervous system: Current status and future perspectives. J Cell Physiol 2018; 234:1001-1007. [DOI: 10.1002/jcp.27084] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 06/29/2018] [Indexed: 12/22/2022]
Affiliation(s)
- Omid Reza Tamtaji
- Physiology Research Center Kashan University of Medical Sciences Kashan Iran
| | | | - Russel J. Reiter
- Department of Cellular and Structural Biology University of Texas Health Science Center San Antonio Texas
| | - Abolfazl Azami
- Anatomical Sciences Research Center Kashan University of Medical Sciences Kashan Iran
| | - Zatollah Asemi
- Research Center for Biochemistry and Nutrition in Metabolic Diseases Kashan University of Medical Sciences Kashan Iran
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Sahu S, Li R, Kadeyala PK, Liu S, Schachner M. The human natural killer-1 (HNK-1) glycan mimetic ursolic acid promotes functional recovery after spinal cord injury in mouse. J Nutr Biochem 2018; 55:219-228. [PMID: 29567576 DOI: 10.1016/j.jnutbio.2018.01.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 11/17/2017] [Accepted: 01/19/2018] [Indexed: 02/05/2023]
Abstract
Human natural killer-1 (HNK-1) cell antigen is a glycan epitope involved in several neural events, such as neuritogenesis, myelination, synaptic plasticity and regeneration of the nervous system after injury. We have recently identified the small organic compound ursolic acid (UA) as a HNK-1 mimetic with the aim to test its therapeutic potential in the central nervous system. UA, a plant-derived pentacyclic triterpenoid, is well known for its multiple biological functions, including neuroprotective, antioxidant and anti-inflammatory activities. In the present study, we evaluated its functions in a mouse model of spinal cord injury (SCI) and explored the molecular mechanisms underlying its positive effects. Oral administration of UA to mice 1 h after SCI and thereafter once daily for 6 weeks enhanced the regaining of motor functions and axonal regrowth, and decreased astrogliosis. UA administration decreased levels of proinflammatory markers, including interleukin-6 and tumor necrosis factor-α, in the injured spinal cord at the acute phase of inflammation and activated the mitogen-activated protein kinase and phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin pathways in the injured spinal cord. Taken together, these results suggest that UA may be a candidate for treatment of nervous system injuries.
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Affiliation(s)
- Sudhanshu Sahu
- Center for Neuroscience, Shantou University Medical College, Shantou, Guangdong 515041, China
| | - Rong Li
- Center for Neuroscience, Shantou University Medical College, Shantou, Guangdong 515041, China
| | - Praveen Kumar Kadeyala
- Center for Neuroscience, Shantou University Medical College, Shantou, Guangdong 515041, China
| | - Shisong Liu
- Center for Neuroscience, Shantou University Medical College, Shantou, Guangdong 515041, China
| | - Melitta Schachner
- Center for Neuroscience, Shantou University Medical College, Shantou, Guangdong 515041, China; Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08554, USA.
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8
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Calpain-2 Regulates TNF-α Expression Associated with Neuropathic Pain Following Motor Nerve Injury. Neuroscience 2018; 376:142-151. [DOI: 10.1016/j.neuroscience.2018.02.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 02/05/2018] [Accepted: 02/14/2018] [Indexed: 11/17/2022]
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Plantier V, Brocard F. [Calpain as a new therapeutic target for treating spasticity after a spinal cord injury]. Med Sci (Paris) 2017; 33:629-636. [PMID: 28990565 DOI: 10.1051/medsci/20173306020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
After a spinal cord injury (SCI), patients develop spasticity, a motor disorder characterized by hyperreflexia and stiffness of muscles. Spasticity results from alterations in motoneurons with an upregulation of their persistent sodium current (I NaP), simultaneously with a disinhibition caused by a reduction of expression of chloride (Cl-) co-transporters KCC2. Until recently the origin of alterations was unknown. After reviewing pathophysiology of spasticity, the manuscript relates our recent work showing a tight relationship between the calpain-dependent proteolysis of voltage-gated sodium channels, the upregulation of I NaP and spasticity following SCI. We also discuss KCC2 as a substrate of calpains which may contribute to the disinhibition of motoneurons below the lesion. This led us to consider the proteolytic cleavage of both sodium channels and KCC2 as the upstream mechanism contributing to the development of spasticity after SCI.
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Affiliation(s)
- Vanessa Plantier
- Équipe P3M, Institut de Neurosciences de la Timone, UMR7289, Aix Marseille Université et Centre National de la Recherche Scientifique (CNRS), Marseille, France
| | - Frédéric Brocard
- Équipe P3M, Institut de Neurosciences de la Timone, UMR7289, Aix Marseille Université et Centre National de la Recherche Scientifique (CNRS), Marseille, France
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Haque A, Capone M, Matzelle D, Cox A, Banik NL. Targeting Enolase in Reducing Secondary Damage in Acute Spinal Cord Injury in Rats. Neurochem Res 2017; 42:2777-2787. [PMID: 28508172 DOI: 10.1007/s11064-017-2291-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 04/24/2017] [Accepted: 05/06/2017] [Indexed: 12/12/2022]
Abstract
Spinal cord injury (SCI) is a complex debilitating condition leading to permanent life-long neurological deficits. The complexity of SCI suggests that a concerted multi-targeted therapeutic approach is warranted to optimally improve function. Damage to spinal cord is complicated by an increased detrimental response from secondary injury factors mediated by activated glial cells and infiltrating macrophages. While elevation of enolase especially neuron specific enolase (NSE) in glial and neuronal cells is believed to trigger inflammatory cascades in acute SCI, alteration of NSE and its subsequent effects in acute SCI remains unknown. This study measured NSE expression levels and key inflammatory mediators after acute SCI and investigated the role of ENOblock, a novel small molecule inhibitor of enolase, in a male Sprague-Dawley (SD) rat SCI model. Serum NSE levels as well as cytokines/chemokines and metabolic factors were evaluated in injured animals following treatment with vehicle alone or ENOblock using Discovery assay. Spinal cord samples were also analyzed for NSE and MMPs 2 and 9 as well as glial markers by Western blotting. The results indicated a significant decrease in serum inflammatory cytokines/chemokines and NSE, alterations of metabolic factors and expression of MMPs in spinal cord tissues after treatment with ENOblock (100 µg/kg, twice). These results support the hypothesis that activation of glial cells and inflammation status can be modulated by regulation of NSE expression and activity. Analysis of SCI tissue samples by immunohistochemistry confirmed that ENOblock decreased gliosis which may have occurred through reduction of elevated NSE in rats. Overall, elevation of NSE is deleterious as it promotes extracellular degradation and production of inflammatory cytokines/chemokines and metabolic factors which activates glia and damages neurons. Thus, reduction of NSE by ENOblock may have potential therapeutic implications in acute SCI.
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Affiliation(s)
- Azizul Haque
- Department of Microbiology and Immunology, Medical University of South Carolina, 173 Ashley Avenue, BSB-201, Charleston, SC, 29425, USA.
| | - Mollie Capone
- Department of Microbiology and Immunology, Medical University of South Carolina, 173 Ashley Avenue, BSB-201, Charleston, SC, 29425, USA
- Ralph H. Johnson Veterans Administration Medical Center, Charleston, SC, USA
| | - Denise Matzelle
- Department of Neurosurgery, Medical University of South Carolina, Charleston, USA
- Ralph H. Johnson Veterans Administration Medical Center, Charleston, SC, USA
| | - April Cox
- FirstString Research, Mt. Pleasant, SC, USA
| | - Naren L Banik
- Department of Microbiology and Immunology, Medical University of South Carolina, 173 Ashley Avenue, BSB-201, Charleston, SC, 29425, USA
- Department of Neurosurgery, Medical University of South Carolina, Charleston, USA
- Ralph H. Johnson Veterans Administration Medical Center, Charleston, SC, USA
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Moghieb A, Bramlett HM, Das JH, Yang Z, Selig T, Yost RA, Wang MS, Dietrich WD, Wang KKW. Differential Neuroproteomic and Systems Biology Analysis of Spinal Cord Injury. Mol Cell Proteomics 2016; 15:2379-95. [PMID: 27150525 PMCID: PMC4937511 DOI: 10.1074/mcp.m116.058115] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Revised: 04/08/2016] [Indexed: 12/13/2022] Open
Abstract
Acute spinal cord injury (SCI) is a devastating condition with many consequences and no known effective treatment. Although it is quite easy to diagnose traumatic SCI, the assessment of injury severity and projection of disease progression or recovery are often challenging, as no consensus biomarkers have been clearly identified. Here rats were subjected to experimental moderate or severe thoracic SCI. At 24h and 7d postinjury, spinal cord segment caudal to injury center versus sham samples was harvested and subjected to differential proteomic analysis. Cationic/anionic-exchange chromatography, followed by 1D polyacrylamide gel electrophoresis, was used to reduce protein complexity. A reverse phase liquid chromatography-tandem mass spectrometry proteomic platform was then utilized to identify proteome changes associated with SCI. Twenty-two and 22 proteins were up-regulated at 24 h and 7 day after SCI, respectively; whereas 19 and 16 proteins are down-regulated at 24 h and 7 day after SCI, respectively, when compared with sham control. A subset of 12 proteins were identified as candidate SCI biomarkers - TF (Transferrin), FASN (Fatty acid synthase), NME1 (Nucleoside diphosphate kinase 1), STMN1 (Stathmin 1), EEF2 (Eukaryotic translation elongation factor 2), CTSD (Cathepsin D), ANXA1 (Annexin A1), ANXA2 (Annexin A2), PGM1 (Phosphoglucomutase 1), PEA15 (Phosphoprotein enriched in astrocytes 15), GOT2 (Glutamic-oxaloacetic transaminase 2), and TPI-1 (Triosephosphate isomerase 1), data are available via ProteomeXchange with identifier PXD003473. In addition, Transferrin, Cathepsin D, and TPI-1 and PEA15 were further verified in rat spinal cord tissue and/or CSF samples after SCI and in human CSF samples from moderate/severe SCI patients. Lastly, a systems biology approach was utilized to determine the critical biochemical pathways and interactome in the pathogenesis of SCI. Thus, SCI candidate biomarkers identified can be used to correlate with disease progression or to identify potential SCI therapeutic targets.
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Affiliation(s)
- Ahmed Moghieb
- From the ‡Program for Neurotrauma, Neuroproteomics & Biomarkers Research, §The Departments of Psychiatry, and ‖Chemistry, University of Florida, Gainesville, Florida 32611
| | - Helen M Bramlett
- **Department of Neurological Surgery, ‡‡The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, 1095 NW 14th Terrace LPLC 3-18, Miami, Florida, 33136
| | - Jyotirmoy H Das
- From the ‡Program for Neurotrauma, Neuroproteomics & Biomarkers Research, §§Washington University School of Medicine, St. Louis, Missouri 63110
| | - Zhihui Yang
- From the ‡Program for Neurotrauma, Neuroproteomics & Biomarkers Research, §The Departments of Psychiatry, and
| | - Tyler Selig
- From the ‡Program for Neurotrauma, Neuroproteomics & Biomarkers Research
| | - Richard A Yost
- ‖Chemistry, University of Florida, Gainesville, Florida 32611
| | - Michael S Wang
- **Department of Neurological Surgery, ‡‡The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, 1095 NW 14th Terrace LPLC 3-18, Miami, Florida, 33136
| | - W Dalton Dietrich
- **Department of Neurological Surgery, ‡‡The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, 1095 NW 14th Terrace LPLC 3-18, Miami, Florida, 33136
| | - Kevin K W Wang
- From the ‡Program for Neurotrauma, Neuroproteomics & Biomarkers Research, §The Departments of Psychiatry, and ¶Neuroscience,
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Saini V, Lutz D, Kataria H, Kaur G, Schachner M, Loers G. The polysialic acid mimetics 5-nonyloxytryptamine and vinorelbine facilitate nervous system repair. Sci Rep 2016; 6:26927. [PMID: 27324620 PMCID: PMC4914991 DOI: 10.1038/srep26927] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 04/07/2016] [Indexed: 02/05/2023] Open
Abstract
Polysialic acid (PSA) is a large negatively charged glycan mainly attached to the neural cell adhesion molecule (NCAM). Several studies have shown that it is important for correct formation of brain circuitries during development and for synaptic plasticity, learning and memory in the adult. PSA also plays a major role in nervous system regeneration following injury. As a next step for clinical translation of PSA based therapeutics, we have previously identified the small organic compounds 5-nonyloxytryptamine and vinorelbine as PSA mimetics. Activity of 5-nonyloxytryptamine and vinorelbine had been confirmed in assays with neural cells from the central and peripheral nervous system in vitro and shown to be independent of their function as serotonin receptor 5-HT1B/1D agonist or cytostatic drug, respectively. As we show here in an in vivo paradigm for spinal cord injury in mice, 5-nonyloxytryptamine and vinorelbine enhance regain of motor functions, axonal regrowth, motor neuron survival and remyelination. These data indicate that 5-nonyloxytryptamine and vinorelbine may be re-tasked from their current usage as a 5-HT1B/1D agonist or cytostatic drug to act as mimetics for PSA to stimulate regeneration after injury in the mammalian nervous system.
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Affiliation(s)
- Vedangana Saini
- Department of Biotechnology, Guru Nanak Dev University, GT Road, 143005 Amritsar, India
- Center for Molecular Neurobiology, University Hospital Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany
| | - David Lutz
- Center for Molecular Neurobiology, University Hospital Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany
| | - Hardeep Kataria
- Center for Molecular Neurobiology, University Hospital Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany
| | - Gurcharan Kaur
- Department of Biotechnology, Guru Nanak Dev University, GT Road, 143005 Amritsar, India
| | - Melitta Schachner
- Keck Center for Collaborative Neurosciences, Rutgers University, Piscataway, NJ 08854, USA
- Center for Neuroscience, Shantou University Medical College, Shantou, Guangdong 515041, People’s Republic of China
| | - Gabriele Loers
- Center for Molecular Neurobiology, University Hospital Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany
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Haque A, Ray SK, Cox A, Banik NL. Neuron specific enolase: a promising therapeutic target in acute spinal cord injury. Metab Brain Dis 2016; 31:487-95. [PMID: 26847611 PMCID: PMC4864119 DOI: 10.1007/s11011-016-9801-6] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 01/26/2016] [Indexed: 12/11/2022]
Abstract
Enolase is a multifunctional protein, which is expressed abundantly in the cytosol. Upon stimulatory signals, enolase can traffic to cell surface and contribute to different pathologies including injury, autoimmunity, infection, inflammation, and cancer. Cell-surface expression of enolase is often detected on activated macrophages, microglia/macrophages, microglia, and astrocytes, promoting extracellular matrix degradation, production of pro-inflammatory cytokines/chemokines, and invasion of inflammatory cells in the sites of injury and inflammation. Inflammatory stimulation also induces translocation of enolase from the cytosolic pool to the cell surface where it can act as a plasminogen receptor and promote extracellular matrix degradation and tissue damage. Spinal cord injury (SCI) is a devastating debilitating condition characterized by progressive pathological changes including complex and evolving molecular cascades, and insights into the role of enolase in multiple inflammatory events have not yet been fully elucidated. Neuronal damage following SCI is associated with an elevation of neuron specific enolase (NSE), which is also known to play a role in the pathogenesis of hypoxic-ischemic brain injury. Thus, NSE is now considered as a biomarker in ischemic brain damage, and it has recently been suggested to be a biomarker in traumatic brain injury (TBI), stroke and anoxic encephalopathy after cardiac arrest and acute SCI as well. This review article gives an overview of the current basic research and clinical studies on the role of multifunctional enolase in neurotrauma, with a special emphasis on NSE in acute SCI.
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Affiliation(s)
- Azizul Haque
- Department of Microbiology and Immunology, Hollings Cancer Center, Medical University of South Carolina, 173 Ashley Avenue, BSB-201, Charleston, SC, 29425, USA.
| | - Swapan K Ray
- Department of Pathology, Microbiology, and Immunology, University of South Carolina School of Medicine, Columbia, SC, 29209, USA
| | - April Cox
- Department of Neurosurgery, Medical University of South Carolina, Charleston, SC, 29425, USA
| | - Naren L Banik
- Department of Neurosurgery, Medical University of South Carolina, Charleston, SC, 29425, USA
- Ralph H. Johnson Veterans Administration Medical Center, 109 Bee Street, Charleston, SC, 29401, USA
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Brocard C, Plantier V, Boulenguez P, Liabeuf S, Bouhadfane M, Viallat-Lieutaud A, Vinay L, Brocard F. Cleavage of Na+ channels by calpain increases persistent Na+ current and promotes spasticity after spinal cord injury. Nat Med 2016; 22:404-11. [DOI: 10.1038/nm.4061] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 02/08/2016] [Indexed: 12/13/2022]
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Zang Y, Chen SX, Liao GJ, Zhu HQ, Wei XH, Cui Y, Na XD, Pang RP, Xin WJ, Zhou LJ, Liu XG. Calpain-2 contributes to neuropathic pain following motor nerve injury via up-regulating interleukin-6 in DRG neurons. Brain Behav Immun 2015; 44:37-47. [PMID: 25150005 DOI: 10.1016/j.bbi.2014.08.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Revised: 07/25/2014] [Accepted: 08/12/2014] [Indexed: 01/09/2023] Open
Abstract
Motor nerve injury by L5 ventral root transection (L5-VRT) initiates interleukin-6 (IL-6) up-regulation in primary afferent system contributing to neuropathic pain. However, the early upstream regulatory mechanisms of IL-6 after L5-VRT are still unknown. Here, we monitored both the activity of calpain, a calcium-dependent protease suggested as one of the earliest mediators for cytokine regulation, and the expression of IL-6 in bilateral L4-L6 dorsal root ganglias (DRGs) soon after L5-VRT. We found that the protein level of calpain-2 in DRGs, but not calpain-1 was increased transiently in the first 10 min(-1)h ipsilaterally and 20 min(-1)h contralaterally after L5-VRT, long before mechanical allodynia was initiated (5-15 h ipsilaterally and 15 h(-1)d contralaterally). The early activation of calpain evaluated by the generation of spectrin breakdown products (SBDP) correlated well with IL-6 up-regulation in bilateral DRGs. Double immunofluorescence staining revealed that almost all the calpain-2 positive neurons expressed IL-6, indicating an association between calpain-2 and IL-6. Inhibition of calpain by pre-treatment with MDL28170 (25mg/kg, i.p.) attenuated the rat mechanical allodynia and prevented the early up-regulation of IL-6 following L5-VRT. Addition of exogenous calpain-2 onto the surface of left L5 DRG triggered a temporal allodynia and increased IL-6 in bilateral DRGs simultaneously. Taken together, the early increase of calpain-2 in L5-VRT rats might be responsible for the induction of allodynia via up-regulating IL-6 in DRG neurons.
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Affiliation(s)
- Ying Zang
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China.
| | - Shao-Xia Chen
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Guang-Jie Liao
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China; Department of Pathology, The Red Cross Hospital of Yulin, 1 Jinwang Rd., Yulin 537000, China
| | - He-Quan Zhu
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Xu-Hong Wei
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Yu Cui
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Xiao-Dong Na
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China; Department of Pathophysiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Rui-Ping Pang
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Wen-Jun Xin
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Li-Jun Zhou
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
| | - Xian-Guo Liu
- Pain Research Center and Department of Physiology, Zhongshan Medical School of Sun Yat-Sen University, 74 Zhongshan Rd. 2, Guangzhou 510080, China
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16
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Takezawa Y, Kohsaka S, Nakajima K. Transient down-regulation and restoration of glycogen synthase levels in axotomized rat facial motoneurons. Brain Res 2014; 1586:34-45. [PMID: 25152465 DOI: 10.1016/j.brainres.2014.08.049] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 08/15/2014] [Accepted: 08/16/2014] [Indexed: 11/19/2022]
Abstract
In adult rats, transection of the facial nerve causes a functional down-regulation of motoneurons and glial activation/proliferation. It has not been clear how energy-supplying systems are regulated in an axotomized facial nucleus. Here we investigated the regulation of molecules involved in glycogen degradation/synthesis in axotomized facial nuclei in rats. Immunoblotting revealed that the amounts of glycogen phosphorylase in the contralateral and ipsilateral nuclei were unchanged for the first 14 days, whereas the amount of glycogen synthase in the axotomized facial nuclei was significantly decreased from days 7-14 post-insult. A quantitative analysis estimated that the glycogen synthase levels in the transected nucleus were reduced to approx. 50% at 14 days post-injury. An immunohistochemical study showed that the injured motoneurons had decreased expressions of glycogen synthase proteins. The glycogen synthase levels in the axotomized facial nucleus had returned to control levels by 5 weeks post-insult, as had the cholinergic markers. The immunohistochemical study also revealed the recovery of glycogen synthase levels at the later stage. The glycogen phosphorylase levels in the injured nucleus were not significantly changed during weeks 3-5 post-insult. Taken together, these results demonstrated that the injured facial motoneurons transiently reduced glycogen synthase levels at around 1-2 weeks post-insult, but restored the levels at 4-5 weeks post-insult.
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Affiliation(s)
- Yosuke Takezawa
- Department of Bioinformatics, Faculty of Engineering, Soka University, Tokyo 192-8577, Japan
| | - Shinichi Kohsaka
- Department of Neurochemistry, National Institute of Neuroscience, Tokyo 187-8502, Japan
| | - Kazuyuki Nakajima
- Department of Bioinformatics, Faculty of Engineering, Soka University, Tokyo 192-8577, Japan.
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Fournier AJ, Rajbhandari L, Shrestha S, Venkatesan A, Ramesh KT. In vitro and in situ visualization of cytoskeletal deformation under load: traumatic axonal injury. FASEB J 2014; 28:5277-87. [PMID: 25205740 DOI: 10.1096/fj.14-251942] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
It is difficult to obtain insight into the mechanisms occurring within live cells during mechanical loading, because this complex environment is dynamic and evolving. This is a particular challenge from a subcellular mechanics perspective, where temporal and spatial information on the evolving cytoskeletal structures is required under loading. Using fluorescently labeled proteins, we visualize 3-dimensional live subcellular cytoskeletal populations under mechanical loading using a high-resolution confocal microscope. The mechanical forces are determined using a computational (finite element) model that is validated by integrating instrumentation into the testing platform. Transfected microtubules and neurofilaments of E17 rat neuronal axons are imaged before, during, and after loading. Comparisons between unloaded and loaded live cells demonstrate both spatial and temporal changes for cytoskeletal populations within the imaged volume. NF signal decreases by 24%, yet the microtubule signal exhibits no significant change 20-35 s after loading. Transmission electron microscopy assesses cytoskeletal structure spatial distribution for undeformed and deformed axons. While cytoskeletal degeneration occurs at prolonged time intervals following loads, our data provides insights into real time cytoskeletal evolution occurring in situ. Our findings suggest that, for axons undergoing traumatic injury in response to applied mechanical loads, changes at the substructural level of neurofilaments may precede microtubule rupture and degeneration.
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Affiliation(s)
- Adam J Fournier
- Mechanical Engineering Department, Johns Hopkins University, Baltimore, Maryland, USA; and
| | - Labchan Rajbhandari
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Shiva Shrestha
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Arun Venkatesan
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - K T Ramesh
- Mechanical Engineering Department, Johns Hopkins University, Baltimore, Maryland, USA; and
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18
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Trager N, Smith A, Wallace Iv G, Azuma M, Inoue J, Beeson C, Haque A, Banik NL. Effects of a novel orally administered calpain inhibitor SNJ-1945 on immunomodulation and neurodegeneration in a murine model of multiple sclerosis. J Neurochem 2014; 130:268-79. [PMID: 24447070 DOI: 10.1111/jnc.12659] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 12/27/2013] [Accepted: 01/15/2014] [Indexed: 12/12/2022]
Abstract
Multiple sclerosis (MS) pathology is marked by the massive infiltration of myelin-specific T cells into the CNS. Hallmarks of T helper (Th) cells during active disease are pro-inflammatory Th1/Th17 cells that predominate over immunoregulatory Th2/Treg cells. Neurodegeneration, a major factor in progressive MS, is often overlooked when considering drug prescription. Here, we show that oral dosing with SNJ-1945, a novel water-soluble calpain inhibitor, reduces experimental autoimmune encephalomyelitis clinical scores in vivo and has a two pronged effect via anti-inflammation and protection against neurodegeneration. We also show that SNJ-1945 treatment down-regulates Th1/Th17 inflammatory responses, and promotes regulatory T cells (Tregs) and myeloid-derived suppressor cells in vivo, which are known to have the capacity to suppress helper as well as cytotoxic T cell functions. Through analysis of spinal cord samples, we show a reduction in calpain expression, decreased infiltration of inflammatory cells, and signs of inhibition of neurodegeneration. We also show a marked reduction in neuronal cell death in spinal cord (SC) sections. These results suggest that calpain inhibition attenuates experimental autoimmune encephalomyelitis pathology by reducing both inflammation and neurodegeneration, and could be used in clinical settings to augment the efficacy of standard immunomodulatory agents used to treat MS. Multiple sclerosis (MS) pathology is marked by inflammation and infiltration of myelin-specific T cells into the central nervous system. Inflammation leads to neurodegeneration in progressive MS which also leads to epitope spreading, feedback looping to more inflammation. Calpain can play a role in both arms of the disease. Here, oral dosing with SNJ-1945, a novel water-soluble calpain inhibitor, reduces experimental autoimmune encephalomyelitis clinical scores in vivo and has a two-pronged effect via anti-inflammation and protection against neurodegeneration.
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Affiliation(s)
- Nicole Trager
- Department of Neurosciences, Medical University of South Carolina, Charleston, South Carolina, USA; Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, South Carolina, USA
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CSF neurofilament light chain is elevated in OMS (decreasing with immunotherapy) and other pediatric neuroinflammatory disorders. J Neuroimmunol 2013; 266:75-81. [PMID: 24342231 DOI: 10.1016/j.jneuroim.2013.11.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 10/15/2013] [Accepted: 11/12/2013] [Indexed: 11/22/2022]
Abstract
Using a panel of seven brain cell-specific biomarkers in cerebrospinal fluid (CSF), pediatric opsoclonus-myoclonus syndrome (OMS) (n=234) was compared to pediatric non-inflammatory neurological controls (n=84) and other inflammatory neurological disorders (OIND) (n=44). Only CSF NFL was elevated in untreated OMS versus controls (+83%). It was 87% higher in OIND than in OMS. On combination treatment with front-loaded ACTH, IVIg, rituximab, median CSF NFL decreased by 60% to control levels. These biochemical data suggest neuronal/axonal injury in some children with OMS without indicators of astrogliosis, and reduction on sufficient immunotherapy.
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20
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Tsutsui S, Stys PK. Metabolic injury to axons and myelin. Exp Neurol 2013; 246:26-34. [DOI: 10.1016/j.expneurol.2012.04.016] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Revised: 03/20/2012] [Accepted: 04/23/2012] [Indexed: 12/31/2022]
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21
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Mild traumatic brain injury in the mouse induces axotomy primarily within the axon initial segment. Acta Neuropathol 2013; 126:59-74. [PMID: 23595276 DOI: 10.1007/s00401-013-1119-4] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 04/08/2013] [Accepted: 04/10/2013] [Indexed: 10/27/2022]
Abstract
Traumatic axonal injury (TAI) is a consistent component of traumatic brain injury (TBI), and is associated with much of its morbidity. Increasingly, it has also been recognized as a major pathology of mild TBI (mTBI). In terms of its pathogenesis, numerous studies have investigated the susceptibility of the nodes of Ranvier, the paranode and internodal regions to TAI. The nodes of Ranvier, with their unique composition and concentration of ion channels, have been suggested as the primary site of injury, initiating a cascade of abnormalities in the related paranodal and internodal domains that lead to local axonal swellings and detachment. No investigation, however, has determined the effect of TAI upon the axon initial segment (AIS), a segment critical to regulating polarity and excitability. The current study sought to identify the susceptibility of these different axon domains to TAI within the neocortex, where each axonal domain could be simultaneously assessed. Utilizing a mouse model of mTBI, a temporal and spatial heterogeneity of axonal injury was found within the neocortical gray matter. Although axonal swellings were found in all domains along myelinated neocortical axons, the majority of TAI occurred within the AIS, which progressed without overt structural disruption of the AIS itself. The finding of primary AIS involvement has important implications regarding neuronal polarity and the fate of axotomized processes, while also raising therapeutic implications, as the mechanisms underlying such axonal injury in the AIS may be distinct from those described for nodal/paranodal injury.
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Abstract
INTRODUCTION Calpains represent a family of neutral, calcium-dependent proteases, which modify the function of their target proteins by partial truncation. These proteases have been implicated in numerous cell functions, including cell division, proliferation, migration, and death. In the CNS, where µ-calpain and m-calpain are the main calpain isoforms, their activation has been linked to synaptic plasticity as well as to neurodegeneration. This review will focus on the role of calpains in synaptic plasticity and discuss the possibility of developing methods to manipulate calpain activity for therapeutic purposes. AREAS COVERED This review covers the literature showing how calpains are implicated in synaptic plasticity and in a number of conditions associated with learning impairment. The possibility of developing new drugs targeting these enzymes for treating these conditions is discussed. EXPERT OPINION As evidence accumulates that calpain activation participates in neurodegeneration and cancer, there is interest in developing therapeutic approaches using direct or indirect calpain inhibition. In particular, a peptide derived from the calpain truncation site of mGluR1α was shown to decrease neurodegeneration following neonatal hypoxia/ischemia. More selective approaches need to be developed to target calpain or some of its substrates for therapeutic indications associated with deregulation of synaptic plasticity.
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Affiliation(s)
- Michel Baudry
- Western University of Health Sciences, Graduate College of Biomedical Sciences, Basic Medical Sciences, COMP , 309 E 2nd St, Pomona, CA 91766, USA.
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23
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Trager N, Butler JT, Haque A, Ray SK, Beeson C, Banik NL. The Involvement of Calpain in CD4 + T Helper Cell Bias in Multple Sclerosis. ACTA ACUST UNITED AC 2013; 4:1000153. [PMID: 24707444 PMCID: PMC3972924 DOI: 10.4172/2155-9899.1000153] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The pathogenesis of multiple sclerosis (MS) is mediated by massive infiltration of myelin-specific T cells into the central nervous system (CNS). Self-reactive CD4+ T helper (Th) cells, specifically Th1 and Th17 cells, are hallmarks of active disease in progression, whereas Th2 cells are predominately in remission stages. Calpain has been shown to be upregulated in the CNS of MS patients and inhibition of calpain has been shown previously to decrease disease in experimental autoimmune encephalomyelitis (EAE), an animal model of MS. We investigated calpain involvement in Thcell bias. Here, we show that calpain inhibition in primary myelin basic protein (MBP) Ac1-11-specific T cells and MBP-specific T cell line cultures increase Th2 proliferation, cytokine profile, and transcription and signaling molecules. We also show a relative decrease in Th1 inflammatory factors in these same categories and a relative decrease in Th17 proliferation. These studies provide insight into the various roles that calpain plays in Th cell bias and proliferation and increases our understanding of the role that T cells play in the pathophysiology of EAE and MS. Results also indicate the mechanisms involved by which calpain inhibitor decreases the disease signs of EAE, suggesting that calpain inhibitor can be a possible therapeutic agent for the treatment of EAE and MS.
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Affiliation(s)
- Nicole Trager
- Department of Neurosciences, Medical University of South Carolina, 96 Jonathan Lucas Street, South Carolina, SC 29425, USA ; Department of Microbiology and Immunology, Hollings Cancer Center, Medical University of South Carolina, 173 Ashley Avenue, South Carolina, SC 29425, USA
| | - Jonathan T Butler
- Vanderbilt Neurosciences, Vanderbilt University, 1211 Medical Center Dr, Nashville, TN 37232, USA
| | - Azizul Haque
- Department of Microbiology and Immunology, Hollings Cancer Center, Medical University of South Carolina, 173 Ashley Avenue, South Carolina, SC 29425, USA
| | - Swapan K Ray
- Department of Pathology, Microbiology, and Immunology, University of South Carolina School of Medicine, 6439 Garners Ferry Road, Columbia, SC 29209, USA
| | - Craig Beeson
- Department of Drug Discovery and Biomedical Science, Medical University of South Carolina, 280 Calhoun Street, Charleston, SC 29425, USA
| | - Naren L Banik
- Department of Neurosciences, Medical University of South Carolina, 96 Jonathan Lucas Street, South Carolina, SC 29425, USA
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25
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Calcium-dependent neutral cysteine protease and organophosphate-induced delayed neuropathy. Chem Biol Interact 2012; 200:114-8. [PMID: 23092810 DOI: 10.1016/j.cbi.2012.10.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Revised: 09/17/2012] [Accepted: 10/03/2012] [Indexed: 11/22/2022]
Abstract
A few organophosphorus compounds (OPs) can cause toxic neuropathy known as organophosphorus ester-induced delayed neuropathy (OPIDN). Although the incidents of OPIDN have been documented for over a century, its molecular mechanisms underlying the axonopathy are still unclear. Recently, increasing evidences suggest that proteases are closely associated with OPIDN. Herein, we have summarized the roles of calcium-dependent cysteine proteases (calpains) in OPIDN. The activation of calpains should be an early molecular event during the onset and development of OPIDN. However, the understanding of the mechanism underlying the disruption of Ca(2+) homeostasis and the activation of calpain by neurotoxic OPs is still limited. Therefore, a better understanding of molecular mechanisms that can prevent the disturbance in cellular Ca(2+) homeostasis can facilitate to establish the novel therapeutic strategies for OPIDN.
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26
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Jefferson SC, Tester NJ, Howland DR. Chondroitinase ABC promotes recovery of adaptive limb movements and enhances axonal growth caudal to a spinal hemisection. J Neurosci 2011; 31:5710-20. [PMID: 21490212 PMCID: PMC3117673 DOI: 10.1523/jneurosci.4459-10.2011] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Revised: 01/17/2011] [Accepted: 02/16/2011] [Indexed: 01/23/2023] Open
Abstract
A number of studies have shown that chondroitinase ABC (Ch'ase ABC) digestion of inhibitory chondroitin sulfate glycosaminoglycans significantly enhances axonal growth and recovery in rodents following spinal cord injury (SCI). Further, our group has shown improved recovery following SCI in the larger cat model. The purpose of the current study was to determine whether intraspinal delivery of Ch'ase ABC, following T10 hemisections in adult cats, enhances adaptive movement features during a skilled locomotor task and/or promotes plasticity of spinal and supraspinal circuitry. Here, we show that Ch'ase ABC enhanced crossing of a peg walkway post-SCI and significantly improved ipsilateral hindlimb trajectories and integration into a functional forelimb-hindlimb coordination pattern. Recovery of these complex movements was associated with significant increases in neurofilament immunoreactivity immediately below the SCI in the ipsilateral white (p = 0.033) and contralateral gray matter (p = 0.003). Further, the rubrospinal tract is critical in the normal cat during skilled movements that require accurate paw placements and trajectories like those seen during peg walkway crossing. Rubrospinal connections were assessed following Fluoro-Gold injections, caudal to the hemisection. Significantly more retrogradely labeled right (axotomized) red nucleus (RN) neurons were seen in Ch'ase ABC-treated (23%) compared with control-treated cats (8%; p = 0.032) indicating that a larger number of RN neurons in Ch'ase ABC-treated cats had axons below the lesion level. Thus, following SCI, Ch'ase ABC may facilitate axonal growth at the spinal level, enhance adaptive features of locomotion, and affect plasticity of rubrospinal circuitry known to support adaptive behaviors in the normal cat.
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Affiliation(s)
- Stephanie C Jefferson
- Brain Rehabilitation and Research Center, Malcom Randall VA Medical Center, Gainesville, North Florida/South Georgia Veterans Health System, Florida 32608, USA
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27
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Kim JH, Loy DN, Wang Q, Budde MD, Schmidt RE, Trinkaus K, Song SK. Diffusion tensor imaging at 3 hours after traumatic spinal cord injury predicts long-term locomotor recovery. J Neurotrauma 2010; 27:587-98. [PMID: 20001686 DOI: 10.1089/neu.2009.1063] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Accurate diagnosis of spinal cord injury (SCI) severity must be achieved before highly aggressive experimental therapies can be tested responsibly in the early phases after trauma. These studies demonstrate for the first time that axial diffusivity (lambda||), derived from diffusion tensor imaging (DTI) within 3 h after SCI, accurately predicts long-term locomotor behavioral recovery in mice. Female C57BL/6 mice underwent sham laminectomy or graded contusive spinal cord injuries at the T9 vertebral level (5 groups, n = 8 for each group). In-vivo DTI examinations were performed immediately after SCI. Longitudinal measurements of hindlimb locomotor recovery were obtained using the Basso mouse scale (BMS). Injured and spared regions of ventrolateral white matter (VLWM) were reliably separated in the hyperacute phase by threshold segmentation. Measurements of lambda|| were compared with histology in the hyperacute phase and 14 days after injury. The spared normal VLWM determined by hyperacute lambda|| and 14-day histology correlated well (r = 0.95). A strong correlation between hindlimb locomotor function recovery and lambda||-determined spared normal VLWM was also observed. The odds of significant locomotor recovery increased by 18% with each 1% increase in normal VLWM measured in the hyperacute phase (odds ratio = 1.18, p = 0.037). The capability of measuring subclinical changes in spinal cord physiology and murine genetic advantages offer an early window into the basic mechanisms of SCI that was not previously possible. Although significant obstacles must still be overcome to derive similar data in human patients, the path to clinical translation is foreseeable and achievable.
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Affiliation(s)
- Joong H Kim
- Department of Radiology, Washington University, St. Louis, Missouri, USA
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28
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Samantaray S, Das A, Thakore NP, Matzelle DD, Reiter RJ, Ray SK, Banik NL. Therapeutic potential of melatonin in traumatic central nervous system injury. J Pineal Res 2009; 47:134-142. [PMID: 19627458 DOI: 10.1111/j.1600-079x.2009.00703.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A vast literature extolling the benefits of melatonin has accumulated during the past four decades. Melatonin was previously considered of importance to seasonal reproduction and circadian rhythmicity. Currently, it appears to be a versatile anti-oxidative and anti-nitrosative agent, a molecule with immunomodulatory actions and profound oncostatic activity, and also to play a role as a potent neuroprotectant. Nowadays, melatonin is sold as a dietary supplement with differential availability as an over-the-counter aid in different countries. There is a widespread agreement that melatonin is nontoxic and safe considering its frequent, long-term usage by humans at both physiological and pharmacological doses with no reported side effects. Endeavors toward a designated drug status for melatonin may be enormously rewarding in clinics for treatment of several forms of neurotrauma where effective pharmacological intervention has not yet been attained. This mini review consolidates the data regarding the efficacy of melatonin as an unique neuroprotective agent in traumatic central nervous system (CNS) injuries. Well-documented actions of melatonin in combating traumatic CNS damage are compiled from various clinical and experimental studies. Research on traumatic brain injury and ischemia/reperfusion are briefly outlined here as they have been recently reviewed elsewhere, whereas the studies on different animal models of the experimental spinal cord injury have been extensively covered in this mini review for the first time.
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Affiliation(s)
- Supriti Samantaray
- Division of Neurology, Department of Neurosciences, Medical University of South Carolina, Charleston, SC
| | - Arabinda Das
- Division of Neurology, Department of Neurosciences, Medical University of South Carolina, Charleston, SC
| | - Nakul P Thakore
- Division of Neurology, Department of Neurosciences, Medical University of South Carolina, Charleston, SC
| | - Denise D Matzelle
- Division of Neurology, Department of Neurosciences, Medical University of South Carolina, Charleston, SC
| | - Russel J Reiter
- Department of Cellular and Structural Biology, University of Texas, San Antonio, TX
| | - Swapan K Ray
- Department of Pathology, Microbiology, and Immunology, University of South Carolina School of Medicine, Columbia, SC, USA
| | - Naren L Banik
- Division of Neurology, Department of Neurosciences, Medical University of South Carolina, Charleston, SC
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29
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Gumy LF, Tan CL, Fawcett JW. The role of local protein synthesis and degradation in axon regeneration. Exp Neurol 2009; 223:28-37. [PMID: 19520073 PMCID: PMC2864402 DOI: 10.1016/j.expneurol.2009.06.004] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 06/02/2009] [Accepted: 06/02/2009] [Indexed: 11/26/2022]
Abstract
In axotomised regenerating axons, the first step toward successful regeneration is the formation of a growth cone. This requires a variety of dynamic morphological and biochemical changes in the axon, including the appearance of many new cytoskeletal, cell surface and signalling molecules. These changes suggest the activation of coordinated complex cellular processes. A recent development has been the demonstration that the regenerative ability of some axons depends on their capacity to locally synthesise new proteins and degrade others at the injury site autonomously from the cell body. There are also events involving the degradation of cytoskeletal and other molecules, and activation of signalling pathways, with axotomy-induced calcium changes probably being an initiating event. A future challenge will be to understand how this complex network of processes interacts in order to find therapeutic ways of promoting the regeneration of CNS axons.
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Affiliation(s)
| | | | - James W. Fawcett
- Corresponding author. Cambridge Centre for Brain Repair, E.D. Adrian Building, Forvie Site, Robinson Way, Cambridge CB2 0PY, UK. Fax: +44 1223 331174.
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30
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Alterations in neurofilaments content and calpains activity of sciatic nerve of carbon disulfide-treated rats. Arch Toxicol 2009; 83:587-94. [DOI: 10.1007/s00204-008-0399-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2008] [Accepted: 12/15/2008] [Indexed: 10/21/2022]
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31
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Yu CG, Joshi A, Geddes JW. Intraspinal MDL28170 microinjection improves functional and pathological outcome following spinal cord injury. J Neurotrauma 2008; 25:833-40. [PMID: 18627259 DOI: 10.1089/neu.2007.0490] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Although calpain (calcium-activated cysteine protease) inhibition represents a rational therapeutic target for spinal cord injury (SCI), few studies have reported improved functional outcomes with post-injury administration of calpain inhibitors. This reflects the weak potency and limited aqueous solubility of current calpain inhibitors. Previously, we demonstrated that intraspinal microinjection of the calpain inhibitor MDL28170 resulted in greater inhibition of calpain activity as compared to systemic administration of the same compound. In the present study, we evaluated the ability of intraspinal MDL28170 microinjection to spare spinal tissue and locomotor dysfunction following SCI. Contusion SCI was produced in female Long-Evans rats using the Infinite Horizon impactor at the 200-kdyn force setting. Open-field locomotion was evaluated until 6 weeks post-injury. Histological assessment of tissue sparing was performed at 6 weeks after SCI. The results demonstrate that MDL28170, administered with a single post-injury intraspinal microinjection (50 nmoles), significantly improves both locomotor function and pathological outcome measures following SCI.
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Affiliation(s)
- Chen-Guang Yu
- Spinal Cord and Brain Injury Research Center, Department of Anatomy and Neurobiology, University of Kentucky, Lexington, Kentucky, USA
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32
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Wang QS, Hou LY, Zhang CL, Zhao XL, Yu SF, Xie KQ. 2,5-hexanedione (HD) treatment alters calmodulin, Ca2+/calmodulin-dependent protein kinase II, and protein kinase C in rats' nerve tissues. Toxicol Appl Pharmacol 2008; 232:60-8. [DOI: 10.1016/j.taap.2008.05.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2007] [Revised: 04/30/2008] [Accepted: 05/19/2008] [Indexed: 11/29/2022]
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33
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Perrot R, Berges R, Bocquet A, Eyer J. Review of the Multiple Aspects of Neurofilament Functions, and their Possible Contribution to Neurodegeneration. Mol Neurobiol 2008; 38:27-65. [DOI: 10.1007/s12035-008-8033-0] [Citation(s) in RCA: 205] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2008] [Accepted: 06/14/2008] [Indexed: 10/21/2022]
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34
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Sun L, Kuroiwa T, Ishibashi S, Miki K, Li S, Xu H, Endo S, Mizusawa H. Two region-dependent pathways of eosinophilic neuronal death after transient cerebral ischemia. Neuropathology 2008; 29:45-54. [PMID: 18627483 DOI: 10.1111/j.1440-1789.2008.00939.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Various types of eosinophilic neurons (ENs) are found in the post-ischemic brain. We examined the temporal profile of ENs in the core and peripheral regions of the ischemic cortex, and analyzed the relationship to the expression of various cell death-related factors. Unilateral forebrain ischemia was induced in Mongolian gerbils by transient common carotid artery occlusions, and the brains from 3 h to 2 weeks post-ischemia were prepared for morphometric and immunohistochemical analysis of ENs. ENs with minimally abnormal nuclei and swollen cell bodies appeared at 3 h in the ischemic core and at 12 h in the periphery. In both locations multiple cell death-related factors including calcium, micro-calpain, cathepsin D, 78 kDa glucose-regulated protein (GRP78) and ubiquitin were activated. In the ischemic core, pyknosis and irregularly atrophic cytoplasm peaked at 12 h, which was associated with significant increases in staining for calcium and micro-calpain. ENs with pyknosis and scant cytoplasm peaked at 4 days and were positive for TUNEL and calcium staining. In the ischemic periphery, ENs had slightly atrophic cytoplasm and sequentially developed pyknosis, karyorrhexis and karyolysis over 1 week. These cells were positive for TUNEL and calcium staining. All types of EN were negative for caspase 3. There may be two region-dependent pathways of EN changes in the post-ischemic brain: pyknosis with cytoplasmic shrinkage in the core, and nuclear disintegration with slightly atrophic cytoplasm in the periphery. This difference coordinates different activation patterns of cell death-related factors in ENs.
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Affiliation(s)
- Liyuan Sun
- Department of Neurology, Graduate School of Medicine, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo, Japan
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35
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Wang QS, Zhang CL, Hou LY, Zhao XL, Yang XW, Xie KQ. Involvement of cyclin-dependent kinase 5 in 2,5-hexanedione-induced neuropathy. Toxicology 2008; 248:1-7. [DOI: 10.1016/j.tox.2008.02.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2008] [Revised: 02/28/2008] [Accepted: 02/28/2008] [Indexed: 10/22/2022]
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36
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37
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Wang QS, Hou LY, Zhang CL, Song FY, Xie KQ. Changes of cytoskeletal proteins in nerve tissues and serum of rats treated with 2,5-hexanedione. Toxicology 2007; 244:166-78. [PMID: 18177991 DOI: 10.1016/j.tox.2007.11.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2007] [Revised: 11/13/2007] [Accepted: 11/14/2007] [Indexed: 11/26/2022]
Abstract
To investigate the mechanisms and biomarker of the neuropathy induced by 2,5-hexanedione (HD), male Wistar rats were administrated HD at dosage of 200 or 400mg/kg for 8 weeks (five-times per week). All rats were sacrificed after 8 weeks of treatment and the cerebrum cortex (CC), spinal cord (SC) and sciatic nerves (SN) were dissected, homogenized and used for the determination of cytoskeletal proteins by western blotting. The levels of neurofilaments (NFs) subunits (NF-L, NF-M and NF-H) in nerve tissues of 200 and 400mg/kg HD rats significantly decreased in both the supernatant and pellet fractions. Furthermore, significant negative correlations between NFs levels and gait abnormality were observed. As for microtubule (MT) and microfilament (MF) proteins, the levels of alpha-tubulin, beta-tubulin and beta-actin in the supernatant and pellet fraction of SN significantly decreased in 200 and 400mg/kg HD rats and correlated negatively with gait abnormality. However, the contents of MT and MF proteins in CC and SC were inconsistently affected and had no significant correlation with gait abnormality. The levels of NF-L and NF-H in serum significantly increased, while NF-M, alpha-tubulin, beta-tubulin and beta-actin contents remain unchanged. A significant positive correlation (R=0.9427, P<0.01) was observed between gait abnormality and NF-H level in serum as the intoxication went on. These findings suggested that HD intoxication resulted in a progressive decline of cytoskeletal protein contents, which might be relevant to the mechanisms of HD-induced neuropathy. NF-H was the most sensitive index, which may serve as a good indicator for neurotoxicity of n-hexane or HD.
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Affiliation(s)
- Qing-Shan Wang
- Institute of Toxicology, Shandong University, 44 West Wenhua Road, Jinan 250012, PR China
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38
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Loy DN, Kim JH, Xie M, Schmidt RE, Trinkaus K, Song SK. Diffusion Tensor Imaging Predicts Hyperacute Spinal Cord Injury Severity. J Neurotrauma 2007; 24:979-90. [PMID: 17600514 DOI: 10.1089/neu.2006.0253] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Experimental strategies that focus on ventral white matter (VWM) preservation during the hyperacute phase hold great potential for our improved understanding of functional recovery following traumatic spinal cord injury (SCI). Critical comparisons of human SCI to rapidly accumulating data derived from rodent models are limited by a basic lack of in vivo measures of subclinical pathophysiologic changes and white matter damage in the spinal cord. Spinal cord edema and intraparenchymal hemorrhage demonstrated with routine MR sequences have limited value for predicting functional outcomes in SCI animal models and in human patients. We recently demonstrated that in vivo derived diffusion tensor imaging (DTI) parameters are sensitive and specific biomarkers for spinal cord white matter damage. In this study, non-invasive in vivo DTI was utilized to evaluate the white matter of C57BL/6 mice 3 h after mild (0.3 mm), moderate (0.6 mm), or severe (0.9 mm) contusive SCI. In the hyperacute phase, relative anisotropy maps provided excellent gray-white matter contrast in all degrees of injury. In vivo DTI-derived measurements of axial diffusion differentiated between mild, moderate, and severe contusive SCI with good histological correlation. Cross-sectional regional measurements of white matter injury severity between dorsal columns and VWM varied with increasing cord displacement in a pattern consistent with spinal cord viscoelastic properties.
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Affiliation(s)
- David N Loy
- Department of Radiology, Washington University, Saint Louis, Missouri 63110, USA
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39
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Yu CG, Geddes JW. Sustained calpain inhibition improves locomotor function and tissue sparing following contusive spinal cord injury. Neurochem Res 2007; 32:2046-53. [PMID: 17476592 DOI: 10.1007/s11064-007-9347-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2007] [Accepted: 04/03/2007] [Indexed: 10/23/2022]
Abstract
Following contusive spinal cord injury (SCI), calpain activity is dramatically increased and remains elevated for days to weeks. Although calpain inhibition has previously been demonstrated to be neuroprotective following spinal cord injury, most studies administered the calpain inhibitor at a single time point. We hypothesized that sustained calpain inhibition would improve functional and pathological outcomes, as compared to the results obtained with a single postinjury administration of the calpain inhibitor. Contusion SCI was produced in female Long-Evans rats using the Infinite Horizon spinal cord injury impactor at the 200 kdyn force setting. Open-field locomotor function was evaluated until 6 weeks postinjury. Histological assessment of lesion volume and tissue sparing was performed at 6 weeks after SCI. Calpain inhibitor MDL28170 administered as a single postinjury i.v. bolus (20 mg/kg) or as a daily i.p. dose (1 mg/kg) improved locomotor function, but did not increase tissue sparing. Combined i.v. and daily i.p. MDL28170 administration resulted in significant improvement in both functional and pathological outcome measures, supporting the calpain theory of SCI proposed by Dr. Banik and colleagues.
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Affiliation(s)
- Chen-Guang Yu
- Spinal Cord and Brain Injury Research Center and Department of Anatomy and Neurobiology, University of Kentucky, Lexington, KY 40536-0509, USA
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40
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Song F, Zhang C, Yu S, Zhao X, Yu L, Xie K. Time-dependent Alteration of Cytoskeletal Proteins in Cerebral Cortex of Rat During 2,5-Hexanedione-induced Neuropathy. Neurochem Res 2007; 32:1407-14. [PMID: 17447142 DOI: 10.1007/s11064-007-9325-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2006] [Accepted: 03/01/2007] [Indexed: 10/23/2022]
Abstract
To investigate the mechanisms of the axonopathy induced by 2,5-hexanedione (2,5-HD), male Wistar rats were administered at a dosage of 400 mg/kg/day 2,5-HD (five times per week). The rats produced a slightly, moderately, or severely abnormal neurological changes, respectively, after 2, 4, or 8 weeks of treatment. The cerebrums were Triton-extracted and ultracentrifuged to yield a pellet fraction and a corresponding supernatant fraction. The relative levels of six cytoskeletal proteins (NF-L, NF-M, NF-H, alpha-tubulin, beta-tubulin, and beta-actin) in both fractions were determined by immunoblotting. The results showed that NFs content in HD-treated rats demonstrated a progressive decline as the intoxication of HD continued. As for microtubule proteins, the levels of alpha-tubulin and beta-tubulin demonstrated some inconsistent changes. The content of alpha-tubulin kept unchangeable, while the content of beta-tubulin increased significantly at the late stage of HD exposure. Furthermore, the content of beta-actin in both fractions remained unaffected throughout the study. These findings suggest that HD intoxication resulted in a progressive decline of NFs, which was highly correlated with the development of HD-induced neuropathy.
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Affiliation(s)
- Fuyong Song
- Institute of Toxicology, Shandong University, 44 West Wenhua Road, Jinan, Shandong, People's Republic of China
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41
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Serbest G, Burkhardt MF, Siman R, Raghupathi R, Saatman KE. Temporal profiles of cytoskeletal protein loss following traumatic axonal injury in mice. Neurochem Res 2007; 32:2006-14. [PMID: 17401646 DOI: 10.1007/s11064-007-9318-9] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2007] [Accepted: 02/20/2007] [Indexed: 10/23/2022]
Abstract
To examine the time course and relative extent of proteolysis of neurofilament and tubulin proteins after traumatic axonal injury (TAI), anesthetized mice were subjected to optic nerve stretch injury. Immunohistochemistry confirmed neurofilament accumulation within axonal swellings at 4, 24, and 72 h postinjury (n = 4 injured and 2 sham per time point). Immunoblotting of optic nerve homogenates (n = 5 injured and 1 sham at 0.5, 4, 24 or 72 h) revealed calpain-mediated spectrin proteolytic fragments after injury. Protein levels for NF68 progressively decreased from 0.5 h to 24 h postinjury, while NF200 and alpha-tubulin levels decreased acutely (0.5-4 h), with a secondary decline at 72 h postinjury. These data demonstrate that diffusely distributed TAI is associated not only with a localized accumulation of neurofilament proteins, but also significant decreases in total cytoskeletal protein levels which may be mediated, in part, by calpains. Protection of the axonal cytoskeleton represents a potential therapeutic target for axonal damage associated with injury or neurodegenerative diseases.
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Affiliation(s)
- Gulyeter Serbest
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA
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42
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Zhang SX, Holmberg EG, Geddes JW. Artifactual dendritic beading in rat spinal cord induced by perfusion with cold saline and paraformaldehyde. J Neurosci Methods 2007; 163:38-43. [PMID: 17397933 DOI: 10.1016/j.jneumeth.2007.02.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2005] [Revised: 02/12/2007] [Accepted: 02/12/2007] [Indexed: 10/23/2022]
Abstract
Extensive dendritic beading of MAP2 (microtubule-associated protein 2) immunoreactivity has previously been observed in the contused rat spinal cord. However, we have also observed dendritic beading in occasional uninjured animals. The purpose of this study was to examine the possibility that perfusion conditions contributed to the dendritic beading. Under deep anesthesia, uninjured rats (adult female Long-Evans, 200-225 g) were transcardially perfused with 0.9% saline solution followed by 4% paraformaldehyde at cold (4 degrees C) or warm (20 degrees C) temperature, and at a low (20 ml/min) or high (50 ml/min) flow rate. Dendrites were visualized by MAP2 immunoreactivity. The results demonstrate that perfusion with cold solutions at a high flow rate induces pronounced dendritic beading, and when perfused at a low flow rate, results in moderate dendritic beading. Warm perfusates did not induce dendritic beading when administered at a low flow rate, but occasional beading was observed with a high flow rate. Western blots revealed spectrin breakdown, but not MAP2 loss, in rats perfused with cold saline solution at a high flow rate, conditions that also resulted in dendritic beading. These findings demonstrate that dendritic morphology is sensitive to both temperature and flow rate of the perfusate. Warm fixative and a low perfusion flow rate minimized the perfusion-induced dendritic beading.
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Affiliation(s)
- Shu-Xin Zhang
- Spinal Cord and Brain Injury Research Center, University of Kentucky College of Medicine, Lexington, KY 40536, USA.
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43
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Xiong Y, Rabchevsky AG, Hall ED. Role of peroxynitrite in secondary oxidative damage after spinal cord injury. J Neurochem 2007; 100:639-49. [PMID: 17181549 DOI: 10.1111/j.1471-4159.2006.04312.x] [Citation(s) in RCA: 153] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Peroxynitrite (PON, ONOO(-)), formed by nitric oxide synthase-generated nitric oxide radical ( NO) and superoxide radical (O(2) (-)), is a crucial player in post-traumatic oxidative damage. In the present study, we determined the spatial and temporal characteristics of PON-derived oxidative damage after a moderate contusion injury in rats. Our results showed that 3-nitrotyrosine (3-NT), a specific marker for PON, rapidly accumulated at early time points (1 and 3 h) and a significant increase compared with sham rats was sustained to 1 week after injury. Additionally, there was a coincident and maintained increase in the levels of protein oxidation-related protein carbonyl and lipid peroxidation-derived 4-hydroxynonenal (4-HNE). The peak increases of 3-NT and 4-HNE were observed at 24 h post-injury. In our immunohistochemical results, the co-localization of 3-NT and 4-HNE results indicates that PON is involved in lipid peroxidative as well as protein nitrative damage. One of the consequences of oxidative damage is an exacerbation of intracellular calcium overload, which activates the cysteine protease calpain leading to the degradation of several cellular targets including cytoskeletal protein (alpha-spectrin). Western blot analysis of alpha-spectrin breakdown products showed that the 145-kDa fragments of alpha-spectrin, which are specifically generated by calpain, were significantly increased as soon as 1 h following injury although the peak increase did not occur until 72 h post-injury. The later activation of calpain is most likely linked to PON-mediated secondary oxidative impairment of calcium homeostasis. Scavengers of PON, or its derived free radical species, may provide an improved antioxidant neuroprotective approach for the treatment of post-traumatic oxidative damage in the injured spinal cord.
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Affiliation(s)
- Yiqin Xiong
- Spinal Cord and Brain Injury Research Center, University of Kentucky Chandler Medical Center, Lexington, KY 40536, USA
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44
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Averna M, Stifanese R, De Tullio R, Passalacqua M, Defranchi E, Salamino F, Melloni E, Pontremoli S. Regulation of Calpain Activity in Rat Brain with Altered Ca2+ Homeostasis. J Biol Chem 2007; 282:2656-65. [PMID: 17135258 DOI: 10.1074/jbc.m606919200] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Activation of calpain occurs as an early event in correlation with an increase in [Ca2+]i induced in rat brain upon treatment with a high salt diet for a prolonged period of time. The resulting sequential events have been monitored in the brain of normal and hypertensive rats of the Milan strain, diverging for a constitutive alteration in the level of [Ca2+]i found to be present in nerve cells of hypertensive animals. After 2 weeks of treatment, the levels of the plasma membrane Ca2+-ATPase and of native calpastatin are profoundly decreased. These degradative processes, more pronounced in the brain of hypertensive rats, are progressively and efficiently compensated in the brain of both rat strains by different incoming mechanisms. Along with calpastatin degradation, 15-kDa still-active inhibitory fragments are accumulated, capable of efficiently replacing the loss of native inhibitor molecules. A partial return to a more efficient control of Ca2+ homeostasis occurs in parallel, assured by an early increase in the expression of Ca2+-ATPase and of calpastatin, both producing, after 12 weeks of a high salt (sodium) diet, the restoration of almost original levels of the Ca2+ pump and of significant amounts of native inhibitor molecules. Thus, conservative calpastatin fragmentation, associated with an increased expression of Ca2+-ATPase and of the calpain natural inhibitor, has been demonstrated to occur in vivo in rat brain. This represents a sequential adaptive response capable of overcoming the effects of calpain activation induced by a moderate long term elevation of [Ca2+]i.
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Affiliation(s)
- Monica Averna
- Department of Experimental Medicine (DIMES), Biochemistry Section, and Centre of Excellence for Biomedical Research, University of Genoa, Viale Benedetto XV, 1-16132 Genoa, Italy
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45
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Sribnick EA, Matzelle DD, Ray SK, Banik NL. Estrogen treatment of spinal cord injury attenuates calpain activation and apoptosis. J Neurosci Res 2006; 84:1064-75. [PMID: 16902996 DOI: 10.1002/jnr.21016] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Spinal cord injury (SCI) is a devastating neurologic injury, and currently, the only recommended pharmacotherapy is high-dose methylprednisolone, which has limited efficacy. Estrogen is a multi-active steroid with anti-oxidant and anti-apoptotic effects. Estrogen may modulate intracellular Ca2+ and prevent inflammation. For this study, male rats were divided into three groups. Sham-group animals received a laminectomy at T12. Injured rats received both laminectomy and 40 gram centimeter force SCI. Estrogen-group rats received 4 mg/kg 17beta-estradiol (estrogen) at 15 min and 24 hr post-injury, and vehicle-group rats received equal volumes of dimethyl sulfoxide. Animals were sacrificed at 48 hr post-injury, and 1-cm segments of the lesion, rostral penumbra, and caudal penumbra were excised. The degradation of 68 kD neurofilament protein (NFP) and estrogen receptors (ER) was examined by Western blot analysis. Protein levels of calpain and the activities of calpain and caspase-3 were also examined. Levels of cytochrome c were determined in both cytosolic and mitochondrial fractions. Cell death with DNA fragmentation was examined using the TUNEL assay. At the lesion, samples from both vehicle and estrogen treated animals showed increased levels of 68 kD NFP degradation, calpain content, calpain activity, cytochrome c release, and degradation of ERalpha and ERbeta, as compared to sham. In the caudal penumbra, estrogen treatment significantly attenuated 68 kD NFP degradation, calpain content, calpain activity, levels of cytosolic cytochrome c, and ERbeta degradation. At the lesion, vehicle-treated animals displayed more TUNEL+ cells, and estrogen treatment significantly attenuated this cell death marker. We conclude that estrogen may inhibit cell death in SCI through calpain inhibition.
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Affiliation(s)
- Eric Anthony Sribnick
- Department of Neurosciences, Division of Neurology, Medical University of South Carolina, Charleston, South Carolina 29425, USA.
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46
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Mansouri B, Henne WM, Oomman SK, Bliss R, Attridge J, Finckbone V, Zeitouni T, Hoffman T, Bahr BA, Strahlendorf HK, Strahlendorf JC. Involvement of calpain in AMPA-induced toxicity to rat cerebellar Purkinje neurons. Eur J Pharmacol 2006; 557:106-14. [PMID: 17188264 DOI: 10.1016/j.ejphar.2006.11.032] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2006] [Revised: 11/09/2006] [Accepted: 11/13/2006] [Indexed: 02/06/2023]
Abstract
AMPA receptor-elicited excitotoxicity is manifested as both a type of programmed cell death termed dark cell degeneration and edematous necrosis, both of which are linked to increased intracellular Ca2+ concentration. The appearance of marked cytoskeletal changes in response to abusive AMPA receptor activation, coupled with increased intracellular Ca2+ concentration suggests activation of various destructive enzymes such as calpains, a family of Ca2+-dependent cysteine proteases. Since calpains and AMPA have been linked to both necrotic cell death and programmed cell death, we sought to determine the role of calpains in mediating both types of AMPA-mediated toxicity in Purkinje neurons of the cerebellum. These studies employed immunohistochemistry for cytoskeletal breakdown products of calpain activity coupled with confocal microscopy and pharmacological interventions with calpain and AMPA receptor antagonists. The present study identifies an early involvement of calpains in mediating AMPA-induced dark cell degeneration, but not edematous necrosis, based upon the effectiveness of AMPA to generate calpain-derived alpha-spectrin cleavage products in cerebellar Purkinje neurons that express dark cell degeneration, and the effectiveness of calpain antagonists, PD150606 and MDL28170, to attenuate AMPA-induced dark cell degeneration. Moreover, the AMPA receptor antagonist CNQX, a proven inhibitor of AMPA-elicited dark cell degeneration, also blocked AMPA-induced increases in alpha-spectrin, further suggesting interplay between abusive AMPA receptor activation, calpain activation and dark cell degeneration. Since AMPA-induced dark cell degeneration possesses morphological changes that resemble those that occur following brain ischemia in vivo, hypoglycemia, or extended seizure episodes, the involvement of calpains as mediators of cell death is potentially far reaching and has widespread therapeutic implications in numerous CNS disorders.
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Affiliation(s)
- Bobbak Mansouri
- Department of Physiology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
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47
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Song F, Zhao X, Zhou G, Zhu Y, Xie K. Carbon Disulfide-Induced Alterations of Neurofilaments and Calpains Content in Rat Spinal Cord. Neurochem Res 2006; 31:1491-9. [PMID: 17120161 DOI: 10.1007/s11064-006-9210-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2006] [Accepted: 10/20/2006] [Indexed: 11/28/2022]
Abstract
To investigate the mechanism of carbon disulfide-induced neuropathy, male Wistar rats were randomly divided into two experimental groups and one control group. The rats in two experimental groups were treated with carbon disulfide by gavage at dosages of 300 and 500 mg/kg/day, respectively, five times per week for 12 weeks. Spinal cords of carbon disulfide-intoxicated rats and their age-matched controls were Triton-extracted and ultracentrifuged to yield a pellet fraction of neurofilament (NF) polymer and a corresponding supernatant fraction. Then, the contents of NF triplet proteins (NF-H, NF-M, NF-L) and two calpain isoforms (m-calpain and mu-calpain) in both fractions were determined by immunoblotting. In the meantime, the mRNA levels of NF-H, NF-M, and NF-L in spinal cords were quantified using reverse transcriptase-polymerase chain reaction. Results showed that in the pellet fraction, the contents of three NF subunits in both treated groups decreased significantly except NF-L in low dose group. In the supernatant fraction, the pattern of NFs alteration varied according to dose-levels. Compared to controls, three neurofilmant subunits in the high dose group displayed significant reduction consistently. However, in the low dose group, they remained unaffected. As for calpains, the contents of mu-calpain in both fractions increased significantly regardless of carbon disulfide dose-levels. Meanwhile, m-calpain demonstrated a significant decline in the supernatant fraction, and remained unchangeable in the pellet fraction compared to the control group. Furthermore, the levels of mRNA expression of NF-H, NF-M, and NF-L genes were elevated consistently in CS(2)-treated groups. These findings suggested that carbon disulfide intoxication was associated with obvious alterations of NFs content in rat spinal cord, which might be involved in the development of carbon disulfide neurotoxicity.
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Affiliation(s)
- Fuyong Song
- Institute of Toxicology, Shandong University, Jinan, Shandong, 250012, People's Republic of China
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Pignol B, Auvin S, Carré D, Marin JG, Chabrier PE. Calpain inhibitors and antioxidants act synergistically to prevent cell necrosis: effects of the novel dual inhibitors (cysteine protease inhibitor and antioxidant) BN 82204 and its pro-drug BN 82270. J Neurochem 2006; 98:1217-28. [PMID: 16895584 DOI: 10.1111/j.1471-4159.2006.03952.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cell death is a common feature observed in neurodegenerative disorders, and is often associated with calpain activation and overproduction of reactive oxygen species (ROS). This study investigated the use of calpain inhibitors and antioxidants in combination to protect cells against necrosis. Maitotoxin (MTX), which induces a massive influx of calcium, was used to provoke neuronal cell death. This toxin increased, in a concentration-dependent manner, both calpain activity and ROS formation. Calpain inhibitors or antioxidants inhibited MTX-induced necrosis only marginally (below 20%), whereas their association protected against cell death by 40-66% in a synergistic manner. BN 82204, which possesses both calpain-cathepsin L inhibitory and antioxidant properties, and its acetylated pro-drug BN 82270, totally protected cells at 100 microm. The pro-drug BN 82270, which had better cell penetration, was twice as effective as the active principle BN 82204 in protecting glioma C6 or neuroblastoma SHSY5Y cells against death. These results suggest the potential therapeutic relevance of using a single molecule with multiple activities (cysteine protease inhibitor/antioxidant), and warrant further in vivo investigations in models of neuronal disorders.
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Affiliation(s)
- Bernadette Pignol
- Department of Neurobiology, Ipsen Research Laboratories, Les Ulis, France.
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Jette N, Coderre E, Nikolaeva MA, Enright PD, Iwata A, Smith DH, Jiang Q, Stys PK. Spatiotemporal distribution of spectrin breakdown products induced by anoxia in adult rat optic nerve in vitro. J Cereb Blood Flow Metab 2006; 26:777-86. [PMID: 16163297 DOI: 10.1038/sj.jcbfm.9600226] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Hypoxic/ischemic and traumatic injury to central nervous system myelinated axons is heavily dependent on accumulation of Ca ions in the axoplasm, itself promoted by Na influx from the extracellular space. Given the high density of nodal Na channels, we hypothesized that nodes of Ranvier might be particularly vulnerable to Ca overload and subsequent damage, as this is the expected locus of maximal Na influx. Adult rat optic nerves were exposed to in vitro anoxia and analyzed immunohistochemically for the presence of spectrin breakdown. Cleavage of spectrin became detectable between 15 and 30 mins of anoxia, and increased homogeneously along the lengths of fibers; localized breakdown was not observed at nodes of Ranvier at any time point analyzed. Spectrin breakdown was also found in glial processes surrounding axons. Confocal imaging of axoplasmic Ca also revealed a gradual and nonlocalized increase as anoxia progressed, without evidence of Ca 'hot-spots' anywhere along the axons at any time between 0 and 30 mins of anoxic exposure in vitro. Calculations of Ca diffusion rates indicated that even if Ca entered or was released focally in axons, this ion would diffuse rapidly into the internodes and likely produce diffuse injury by activating Ca-dependent proteases. Western blot analysis for voltage-gated Na channel protein revealed that key functional proteins such as these are also degraded by anoxia/ischemia. Thus, proteolysis of structural and functional proteins will conspire to irreversibly injure central axons and render them nonfunctional, eventually leading to transection, degradation, and Wallerian degeneration.
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Affiliation(s)
- Nathalie Jette
- Ottawa Health Research Institute, Division of Neuroscience, University of Ottawa, Ottawa, Ontario, Canada
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BANIK NL, SHIELDS DC, RAY S, DAVIS B, MATZELLE D, WILFORD G, HOGAN EL. Role of Calpain in Spinal Cord Injury: Effects of Calpain and Free Radical Inhibitorsa. Ann N Y Acad Sci 2006; 844:131-137. [DOI: 10.1111/j.1749-6632.1998.tb08228.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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