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Nheu D, Petratos S. How does Nogo-A signalling influence mitochondrial function during multiple sclerosis pathogenesis? Neurosci Biobehav Rev 2024; 163:105767. [PMID: 38885889 DOI: 10.1016/j.neubiorev.2024.105767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Revised: 05/30/2024] [Accepted: 06/08/2024] [Indexed: 06/20/2024]
Abstract
Multiple sclerosis (MS) is a severe neurological disorder that involves inflammation in the brain, spinal cord and optic nerve with key disabling neuropathological outcomes being axonal damage and demyelination. When degeneration of the axo-glial union occurs, a consequence of inflammatory damage to central nervous system (CNS) myelin, dystrophy and death can lead to large membranous structures from dead oligodendrocytes and degenerative myelin deposited in the extracellular milieu. For the first time, this review covers mitochondrial mechanisms that may be operative during MS-related neurodegenerative changes directly activated during accumulating extracellular deposits of myelin associated inhibitory factors (MAIFs), that include the potent inhibitor of neurite outgrowth, Nogo-A. Axonal damage may occur when Nogo-A binds to and signals through its cognate receptor, NgR1, a multimeric complex, to initially stall axonal transport and limit the delivery of important growth-dependent cargo and subcellular organelles such as mitochondria for metabolic efficiency at sites of axo-glial disintegration as a consequence of inflammation. Metabolic efficiency in axons fails during active demyelination and progressive neurodegeneration, preceded by stalled transport of functional mitochondria to fuel axo-glial integrity.
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Affiliation(s)
- Danica Nheu
- Department of Neuroscience, School of Translational Medicine, Monash University, Prahran, VIC 3004, Australia
| | - Steven Petratos
- Department of Neuroscience, School of Translational Medicine, Monash University, Prahran, VIC 3004, Australia.
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2
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Pryce G, Sisay S, Giovannoni G, Selwood DL, Baker D. Neuroprotection in an Experimental Model of Multiple Sclerosis via Opening of Big Conductance, Calcium-Activated Potassium Channels. Pharmaceuticals (Basel) 2023; 16:972. [PMID: 37513884 PMCID: PMC10383993 DOI: 10.3390/ph16070972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 07/02/2023] [Accepted: 07/05/2023] [Indexed: 07/30/2023] Open
Abstract
Big conductance calcium-activated (BK) channel openers can inhibit pathologically driven neural hyperactivity to control symptoms via hyperpolarizing signals to limit neural excitability. We hypothesized that BK channel openers would be neuroprotective during neuroinflammatory, autoimmune disease. The neurodegenerative disease was induced in a mouse experimental autoimmune encephalomyelitis model with translational value to detect neuroprotection in multiple sclerosis. Following the treatment with the BK channel openers, BMS-204253 and VSN16R, neuroprotection was assessed using subjective and objective clinical outcomes and by quantitating spinal nerve content. Treatment with BMS-204253 and VSN16R did not inhibit the development of relapsing autoimmunity, consistent with minimal channel expression via immune cells, nor did it change leukocyte levels in rodents or humans. However, it inhibited the accumulation of nerve loss and disability as a consequence of autoimmunity. Therefore, in addition to symptom control, BK channel openers have the potential to save nerves from excitotoxic damage and could be useful as either stand-alone neuroprotective agents or as add-ons to current disease-modifying treatments that block relapsing MS but do not have any direct neuroprotective activity.
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Affiliation(s)
- Gareth Pryce
- BartsMS, The Blizard Institute, Faculty of Medicine and Dentistry, Queen Mary University of London, London E1 2AT, UK
| | - Sofia Sisay
- BartsMS, The Blizard Institute, Faculty of Medicine and Dentistry, Queen Mary University of London, London E1 2AT, UK
| | - Gavin Giovannoni
- BartsMS, The Blizard Institute, Faculty of Medicine and Dentistry, Queen Mary University of London, London E1 2AT, UK
| | - David L Selwood
- Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - David Baker
- BartsMS, The Blizard Institute, Faculty of Medicine and Dentistry, Queen Mary University of London, London E1 2AT, UK
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3
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Breville G, Sukockiene E, Vargas MI, Lascano AM. Emerging biomarkers to predict clinical outcomes in Guillain-Barré syndrome. Expert Rev Neurother 2023; 23:1201-1215. [PMID: 37902064 DOI: 10.1080/14737175.2023.2273386] [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: 04/18/2023] [Accepted: 10/17/2023] [Indexed: 10/31/2023]
Abstract
INTRODUCTION Guillain-Barré syndrome (GBS) is an immune-mediated poly(radiculo)neuropathy with a variable clinical outcome. Identifying patients who are at risk of suffering from long-term disabilities is a great challenge. Biomarkers are useful to confirm diagnosis, monitor disease progression, and predict outcome. AREAS COVERED The authors provide an overview of the diagnostic and prognostic biomarkers for GBS, which are useful for establishing early treatment strategies and follow-up care plans. EXPERT OPINION Detecting patients at risk of developing a severe outcome may improve management of disease progression and limit potential complications. Several clinical factors are associated with poor prognosis: higher age, presence of diarrhea within 4 weeks of symptom onset, rapid and severe weakness progression, dysautonomia, decreased vital capacity and facial, bulbar, and neck weakness. Biological, neurophysiological and imaging measures of unfavorable outcome include multiple anti-ganglioside antibodies elevation, increased serum and CSF neurofilaments light (NfL) and heavy chain, decreased NfL CSF/serum ratio, hypoalbuminemia, nerve conduction study with early signs of demyelination or axonal loss and enlargement of nerve cross-sectional area on ultrasound. Depicting prognostic biomarkers aims at predicting short-term mortality and need for cardio-pulmonary support, long-term patient functional outcome, guiding treatment decisions and monitoring therapeutic responses in future clinical trials.
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Affiliation(s)
- Gautier Breville
- Neurology Division, Neuroscience Department, University Hospitals of Geneva, Geneva, Switzerland
| | - Egle Sukockiene
- Neurology Division, Neuroscience Department, University Hospitals of Geneva, Geneva, Switzerland
| | - Maria Isabel Vargas
- Neuroradiology Division, University Hospitals of Geneva, Geneva, Switzerland
- Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Agustina M Lascano
- Neurology Division, Neuroscience Department, University Hospitals of Geneva, Geneva, Switzerland
- Faculty of Medicine, University of Geneva, Geneva, Switzerland
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4
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Ren J, Yu F, Greenberg BM. ATP line splitting in association with reduced intracellular magnesium and pH: a brain 31 P MR spectroscopic imaging (MRSI) study of pediatric patients with myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGADs). NMR IN BIOMEDICINE 2023; 36:e4836. [PMID: 36150743 DOI: 10.1002/nbm.4836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 09/06/2022] [Accepted: 09/18/2022] [Indexed: 06/16/2023]
Abstract
Over the past four decades, ATP, the obligatory energy molecule for keeping all cells alive and functioning, has been thought to contribute only one set of signals in brain 31 P MR spectra. Here we report for the first time the observation of two separate β-ATP peaks in brain spectra acquired from patients with myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGADs) using 3D MRSI at 7 T. In voxel spectra with β-ATP line splitting, these two peaks are separated by 0.46 ± 0.18 ppm (n = 6). Spectral lineshape analysis indicates that the upper field β-ATP peak is smaller in relative intensity (24 ± 11% versus 76 ± 11%), and narrower in linewidth (56.8 ± 10.3 versus 41.2 ± 10.3 Hz) than the downfield one. Data analysis also reveals a similar line splitting for the intracellular inorganic phosphate (Pi ) signal, which is characterized by two components with a smaller separation (0.16 ± 0.09 ppm) and an intensity ratio (26 ± 7%:74 ± 7%) comparable to that of β-ATP. While the major components of Pi and β-ATP correspond to a neutral intracellular pH (6.99 ± 0.01) and a free Mg2+ level (0.18 ± 0.02 mM, by Iotti's conversion formula) as found in healthy subjects, their minor counterparts relate to a slightly acidic pH (6.86 ± 0.07) and a 50% lower [Mg2+ ] (0.09 ± 0.02 mM), respectively. Data correlation between β-ATP and Pi signals appears to suggest an association between an increased [H+ ] and a reduced [Mg2+ ] in MOGAD patients.
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Affiliation(s)
- Jimin Ren
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Fang Yu
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Benjamin M Greenberg
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX, USA
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5
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Ganesh A, Reis IR, Varma M, Patry DG, Cooke LJ. Neurological and Head/Eyes/Ears/Nose/Throat Manifestations of COVID-19: A Systematic Review and Meta-Analysis. Can J Neurol Sci 2022; 49:514-531. [PMID: 34287109 PMCID: PMC8460425 DOI: 10.1017/cjn.2021.180] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 07/10/2021] [Accepted: 07/15/2021] [Indexed: 12/18/2022]
Abstract
BACKGROUND/OBJECTIVE Coronavirus disease 2019 (COVID-19) has been associated with various neurological and atypical head/eyes/ears/nose/throat (HEENT) manifestations. We sought to review the evidence for these manifestations. METHODS In this systematic review and meta-analysis, we compiled studies published until March 31, 2021 that examined non-respiratory HEENT, central, and peripheral nervous system presentations in COVID-19 patients. We included 477 studies for qualitative synthesis and 59 studies for meta-analyses. RESULTS Anosmia, ageusia, and conjunctivitis may precede typical upper/lower respiratory symptoms. Central nervous system (CNS) manifestations include stroke and encephalopathy, potentially with brainstem or cranial nerve involvement. MRI studies support CNS para-/postinfectious etiologies, but direct neuroinvasion seems very rare, with few cases detecting Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in the CNS. Peripheral nervous system (PNS) manifestations include muscle damage, Guillain-Barre syndrome (GBS), and its variants. There was moderate-to-high study heterogeneity and risk of bias. In random-effects meta-analyses, anosmia/ageusia was estimated to occur in 56% of COVID-19 patients (95% CI: 0.41-0.71, I2:99.9%), more commonly than in patients without COVID-19 (OR: 14.28, 95% CI: 8.39-24.29, I2: 49.0%). Neurological symptoms were estimated to occur in 36% of hospitalized patients (95% CI: 0.31-0.42, I2: 99.8%); ischemic stroke in 3% (95% CI: 0.03-0.04, I2: 99.2%), and GBS in 0.04% (0.033%-0.047%), more commonly than in patients without COVID-19 (OR[stroke]: 2.53, 95% CI: 1.16-5.50, I2: 76.4%; OR[GBS]: 3.43,1.15-10.25, I2: 89.1%). CONCLUSIONS Current evidence is mostly from retrospective cohorts or series, largely in hospitalized or critically ill patients, not representative of typical community-dwelling patients. There remains a paucity of systematically gathered prospective data on neurological manifestations. Nevertheless, these findings support a high index of suspicion to identify HEENT/neurological presentations in patients with known COVID-19, and to test for COVID-19 in patients with such presentations at risk of infection.
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Affiliation(s)
- Aravind Ganesh
- Department of Clinical Neurosciences, University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada
| | - Isabella R. Reis
- Department of Medicine, Faculty of Health Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Malavika Varma
- Department of Emergency Medicine, University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada
| | - David G. Patry
- Department of Clinical Neurosciences, University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada
| | - Lara J. Cooke
- Department of Clinical Neurosciences, University of Calgary Cumming School of Medicine, Calgary, Alberta, Canada
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El Mendili MM, Grapperon AM, Dintrich R, Stellmann JP, Ranjeva JP, Guye M, Verschueren A, Attarian S, Zaaraoui W. Alterations of Microstructure and Sodium Homeostasis in Fast Amyotrophic Lateral Sclerosis Progressors: A Brain DTI and Sodium MRI Study. AJNR Am J Neuroradiol 2022; 43:984-990. [PMID: 35772800 DOI: 10.3174/ajnr.a7559] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 05/10/2022] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND PURPOSE While conventional MR imaging has limited value in amyotrophic lateral sclerosis, nonconventional MR imaging has shown alterations of microstructure using diffusion MR imaging and recently sodium homeostasis with sodium MR imaging. We aimed to investigate the topography of brain regions showing combined microstructural and sodium homeostasis alterations in amyotrophic lateral sclerosis subgroups according to their disease-progression rates. MATERIALS AND METHODS Twenty-nine patients with amyotrophic lateral sclerosis and 24 age-matched healthy controls were recruited. Clinical assessments included disease duration and the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale. Patients were clinically differentiated into fast (n = 13) and slow (n = 16) progressors according to the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale progression rate. 3T MR imaging brain protocol included 1H T1-weighted and diffusion sequences and a 23Na density-adapted radial sequence. Quantitative maps of diffusion with fractional anisotropy, mean diffusivity, and total sodium concentration were measured. The topography of diffusion and sodium abnormalities was assessed by voxelwise analyses. RESULTS Patients with amyotrophic lateral sclerosis showed significantly higher sodium concentrations and lower fractional anisotropy, along with higher sodium concentrations and higher mean diffusivity compared with healthy controls, primarily within the corticospinal tracts, corona radiata, and body and genu of the corpus callosum. Fast progressors showed wider-spread abnormalities mainly in the frontal areas. In slow progressors, only fractional anisotropy measures showed abnormalities compared with healthy controls, localized in focal regions of the corticospinal tracts, the body of corpus callosum, corona radiata, and thalamic radiation. CONCLUSIONS The present study evidenced widespread combined microstructural and sodium homeostasis brain alterations in fast amyotrophic lateral sclerosis progressors.
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Affiliation(s)
- M M El Mendili
- From the Aix Marseille University (M.M.E.M., A.-M.G., R.D., J.-P.S., J.-P.R., M.G., A.V., W.Z.), Centre national de la recherche scientifique, The Center for Magnetic Resonance in Biology and Medicine, Marseille, France .,APHM, Hopital de la Timone (M.M.E.M., A.-M.G., R.D., J.-P.S., J.-P.R., M.G., A.V., W.Z.), CEMEREM, Marseille, France
| | - A-M Grapperon
- From the Aix Marseille University (M.M.E.M., A.-M.G., R.D., J.-P.S., J.-P.R., M.G., A.V., W.Z.), Centre national de la recherche scientifique, The Center for Magnetic Resonance in Biology and Medicine, Marseille, France.,APHM, Hopital de la Timone (M.M.E.M., A.-M.G., R.D., J.-P.S., J.-P.R., M.G., A.V., W.Z.), CEMEREM, Marseille, France.,APHM, Hôpital de la Timone (A.-M.G., R.D., S.A.), Referral Centre for Neuromuscular Diseases and ALS, Marseille, France
| | - R Dintrich
- From the Aix Marseille University (M.M.E.M., A.-M.G., R.D., J.-P.S., J.-P.R., M.G., A.V., W.Z.), Centre national de la recherche scientifique, The Center for Magnetic Resonance in Biology and Medicine, Marseille, France.,APHM, Hopital de la Timone (M.M.E.M., A.-M.G., R.D., J.-P.S., J.-P.R., M.G., A.V., W.Z.), CEMEREM, Marseille, France.,APHM, Hôpital de la Timone (A.-M.G., R.D., S.A.), Referral Centre for Neuromuscular Diseases and ALS, Marseille, France
| | - J-P Stellmann
- From the Aix Marseille University (M.M.E.M., A.-M.G., R.D., J.-P.S., J.-P.R., M.G., A.V., W.Z.), Centre national de la recherche scientifique, The Center for Magnetic Resonance in Biology and Medicine, Marseille, France.,APHM, Hopital de la Timone (M.M.E.M., A.-M.G., R.D., J.-P.S., J.-P.R., M.G., A.V., W.Z.), CEMEREM, Marseille, France
| | - J-P Ranjeva
- From the Aix Marseille University (M.M.E.M., A.-M.G., R.D., J.-P.S., J.-P.R., M.G., A.V., W.Z.), Centre national de la recherche scientifique, The Center for Magnetic Resonance in Biology and Medicine, Marseille, France.,APHM, Hopital de la Timone (M.M.E.M., A.-M.G., R.D., J.-P.S., J.-P.R., M.G., A.V., W.Z.), CEMEREM, Marseille, France
| | - M Guye
- From the Aix Marseille University (M.M.E.M., A.-M.G., R.D., J.-P.S., J.-P.R., M.G., A.V., W.Z.), Centre national de la recherche scientifique, The Center for Magnetic Resonance in Biology and Medicine, Marseille, France.,APHM, Hopital de la Timone (M.M.E.M., A.-M.G., R.D., J.-P.S., J.-P.R., M.G., A.V., W.Z.), CEMEREM, Marseille, France
| | - A Verschueren
- From the Aix Marseille University (M.M.E.M., A.-M.G., R.D., J.-P.S., J.-P.R., M.G., A.V., W.Z.), Centre national de la recherche scientifique, The Center for Magnetic Resonance in Biology and Medicine, Marseille, France.,APHM, Hopital de la Timone (M.M.E.M., A.-M.G., R.D., J.-P.S., J.-P.R., M.G., A.V., W.Z.), CEMEREM, Marseille, France
| | - S Attarian
- APHM, Hôpital de la Timone (A.-M.G., R.D., S.A.), Referral Centre for Neuromuscular Diseases and ALS, Marseille, France
| | - W Zaaraoui
- From the Aix Marseille University (M.M.E.M., A.-M.G., R.D., J.-P.S., J.-P.R., M.G., A.V., W.Z.), Centre national de la recherche scientifique, The Center for Magnetic Resonance in Biology and Medicine, Marseille, France.,APHM, Hopital de la Timone (M.M.E.M., A.-M.G., R.D., J.-P.S., J.-P.R., M.G., A.V., W.Z.), CEMEREM, Marseille, France
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7
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Sen S, Lagas S, Roy A, Kumar H. Cytoskeleton saga: Its regulation in normal physiology and modulation in neurodegenerative disorders. Eur J Pharmacol 2022; 925:175001. [PMID: 35525310 DOI: 10.1016/j.ejphar.2022.175001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/31/2022] [Accepted: 04/29/2022] [Indexed: 11/25/2022]
Abstract
Cells are fundamental units of life. To ensure the maintenance of homeostasis, integrity of structural and functional counterparts is needed to be essentially balanced. The cytoskeleton plays a vital role in regulating the cellular morphology, signalling and other factors involved in pathological conditions. Microtubules, actin (microfilaments), intermediate filaments (IF) and their interactions are required for these activities. Various proteins associated with these components are primary requirements for directing their functions. Disruption of this organization due to faulty genetics, oxidative stress or impaired transport mechanisms are the major causes of dysregulated signalling cascades leading to various pathological conditions like Alzheimer's (AD), Parkinson's (PD), Huntington's disease (HD) or amyotrophic lateral sclerosis (ALS), hereditary spastic paraplegia (HSP) or any traumatic injury like spinal cord injury (SCI). Novel or conventional therapeutic approaches may be specific or non-specific, targeting either three basic components of the cytoskeleton or various cascades that serve as a cue to numerous pathways like ROCK signalling or the GSK-3β pathway. An enormous number of drugs have been redirected for modulating the cytoskeletal dynamics and thereby may pave the way for inhibiting the progression of these diseases and their complications.
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Affiliation(s)
- Santimoy Sen
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Ahmedabad, Gandhinagar, Gujarat, India
| | - Sheetal Lagas
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Ahmedabad, Gandhinagar, Gujarat, India
| | - Abhishek Roy
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Ahmedabad, Gandhinagar, Gujarat, India
| | - Hemant Kumar
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER)-Ahmedabad, Gandhinagar, Gujarat, India.
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8
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Cheng M, Wang H, Yang G, Cheng Y, Yang Z, Chen X, Liu Y, Sun Z. Sustained developmental endothelial locus-1 overexpression promotes spinal cord injury recovery in mice through the SIRT1/SERCA2 signaling pathway. Brain Res Bull 2022; 181:65-76. [DOI: 10.1016/j.brainresbull.2022.01.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 01/04/2022] [Accepted: 01/22/2022] [Indexed: 11/16/2022]
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9
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Orem BC, Rajaee A, Stirling DP. Inhibiting Calcium Release from Ryanodine Receptors Protects Axons after Spinal Cord Injury. J Neurotrauma 2022; 39:311-319. [PMID: 34913747 PMCID: PMC8817717 DOI: 10.1089/neu.2021.0350] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Ryanodine receptors (RyRs) mediate calcium release from calcium stores and have been implicated in axonal degeneration. Here, we use an intravital imaging approach to determine axonal fate after spinal cord injury (SCI) in real-time and assess the efficacy of ryanodine receptor inhibition as a potential therapeutic approach to prevent intra-axonal calcium-mediated axonal degeneration. Adult 6-8 week old Thy1YFP transgenic mice that express YFP in axons, as well as triple transgenic Avil-Cre:Ai9:Ai95 mice that express the genetically-encoded calcium indicator GCaMP6f in tdTomato positive axons, were used to visualize axons and calcium changes in axons, respectively. Mice received a mild SCI at the T12 level of the spinal cord. Ryanodine, a RyR antagonist, was given at a concentration of 50 μM intrathecally within 15 min of SCI or delayed 3 h after injury and compared with vehicle-treated mice. RyR inhibition within 15 min of SCI significantly reduced axonal spheroid formation from 1 h to 24 h after SCI and increased axonal survival compared with vehicle controls. Delayed ryanodine treatment increased axonal survival and reduced intra-axonal calcium levels at 24 h after SCI but had no effect on axonal spheroid formation. Together, our results support a role for RyR in secondary axonal degeneration.
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Affiliation(s)
- Ben C. Orem
- Kentucky Spinal Cord Injury Research Center, University of Louisville, School of Medicine, Louisville, Kentucky, USA
- Department of Anatomical Sciences and Neurobiology, University of Louisville, School of Medicine, Louisville, Kentucky, USA
| | - Arezoo Rajaee
- Kentucky Spinal Cord Injury Research Center, University of Louisville, School of Medicine, Louisville, Kentucky, USA
- Department of Neurological Surgery, University of Louisville, School of Medicine, Louisville, Kentucky, USA
| | - David P. Stirling
- Kentucky Spinal Cord Injury Research Center, University of Louisville, School of Medicine, Louisville, Kentucky, USA
- Department of Neurological Surgery, University of Louisville, School of Medicine, Louisville, Kentucky, USA
- Department of Anatomical Sciences and Neurobiology, University of Louisville, School of Medicine, Louisville, Kentucky, USA
- Department of Microbiology and Immunology, University of Louisville, School of Medicine, Louisville, Kentucky, USA
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10
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Gorman KM, Peters CH, Lynch B, Jones L, Bassett DS, King MD, Ruben PC, Rosch RE. Persistent sodium currents in SCN1A developmental and degenerative epileptic dyskinetic encephalopathy. Brain Commun 2021; 3:fcab235. [PMID: 34755109 PMCID: PMC8568850 DOI: 10.1093/braincomms/fcab235] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 06/15/2021] [Accepted: 06/21/2021] [Indexed: 11/14/2022] Open
Abstract
Pathogenic variants in the voltage-gated sodium channel gene (SCN1A) are amongst the most common genetic causes of childhood epilepsies. There is considerable heterogeneity in both the types of causative variants and associated phenotypes; a recent expansion of the phenotypic spectrum of SCN1A associated epilepsies now includes an early onset severe developmental and epileptic encephalopathy with regression and a hyperkinetic movement disorder. Herein, we report a female with a developmental and degenerative epileptic-dyskinetic encephalopathy, distinct and more severe than classic Dravet syndrome. Clinical diagnostics indicated a paternally inherited c.5053G>T; p. A1685S variant of uncertain significance in SCN1A. Whole-exome sequencing detected a second de novo mosaic (18%) c.2345G>A; p. T782I likely pathogenic variant in SCN1A (maternal allele). Biophysical characterization of both mutant channels in a heterologous expression system identified gain-of-function effects in both, with a milder shift in fast inactivation of the p. A1685S channels; and a more severe persistent sodium current in the p. T782I. Using computational models, we show that large persistent sodium currents induce hyper-excitability in individual cortical neurons, thus relating the severe phenotype to the empirically quantified sodium channel dysfunction. These findings further broaden the phenotypic spectrum of SCN1A associated epilepsies and highlight the importance of testing for mosaicism in epileptic encephalopathies. Detailed biophysical evaluation and computational modelling further highlight the role of gain-of-function variants in the pathophysiology of the most severe phenotypes associated with SCN1A.
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Affiliation(s)
- Kathleen M Gorman
- Department of Neurology and Clinical Neurophysiology, Children's Health Ireland at Temple Street, Dublin, Ireland.,School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
| | - Colin H Peters
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, Canada.,Department of Physiology and Biophysics, University of Colorado, Denver, CO, USA
| | - Bryan Lynch
- Department of Neurology and Clinical Neurophysiology, Children's Health Ireland at Temple Street, Dublin, Ireland
| | - Laura Jones
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, Canada
| | - Dani S Bassett
- Departments of Bioengineering, Electrical & Systems Engineering, Physics & Astronomy, Neurology, and Psychiatry, University of Pennsylvania, Philadelphia, PA, USA.,Santa Fe Institute, Santa Fe, NM, USA
| | - Mary D King
- Department of Neurology and Clinical Neurophysiology, Children's Health Ireland at Temple Street, Dublin, Ireland.,School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
| | - Peter C Ruben
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, Canada
| | - Richard E Rosch
- Department of Paediatric Neurology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK.,Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA.,MRC Centre for Neurodevelopmental Disorders, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
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11
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Duncan GJ, Simkins TJ, Emery B. Neuron-Oligodendrocyte Interactions in the Structure and Integrity of Axons. Front Cell Dev Biol 2021; 9:653101. [PMID: 33763430 PMCID: PMC7982542 DOI: 10.3389/fcell.2021.653101] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 02/15/2021] [Indexed: 12/12/2022] Open
Abstract
The myelination of axons by oligodendrocytes is a highly complex cell-to-cell interaction. Oligodendrocytes and axons have a reciprocal signaling relationship in which oligodendrocytes receive cues from axons that direct their myelination, and oligodendrocytes subsequently shape axonal structure and conduction. Oligodendrocytes are necessary for the maturation of excitatory domains on the axon including nodes of Ranvier, help buffer potassium, and support neuronal energy metabolism. Disruption of the oligodendrocyte-axon unit in traumatic injuries, Alzheimer's disease and demyelinating diseases such as multiple sclerosis results in axonal dysfunction and can culminate in neurodegeneration. In this review, we discuss the mechanisms by which demyelination and loss of oligodendrocytes compromise axons. We highlight the intra-axonal cascades initiated by demyelination that can result in irreversible axonal damage. Both the restoration of oligodendrocyte myelination or neuroprotective therapies targeting these intra-axonal cascades are likely to have therapeutic potential in disorders in which oligodendrocyte support of axons is disrupted.
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Affiliation(s)
- Greg J Duncan
- Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, Portland, OR, United States
| | - Tyrell J Simkins
- Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, Portland, OR, United States.,Vollum Institute, Oregon Health & Science University, Portland, OR, United States.,Department of Neurology, VA Portland Health Care System, Portland, OR, United States
| | - Ben Emery
- Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health & Science University, Portland, OR, United States
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12
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Beutel T, Dzimiera J, Kapell H, Engelhardt M, Gass A, Schirmer L. Cortical projection neurons as a therapeutic target in multiple sclerosis. Expert Opin Ther Targets 2020; 24:1211-1224. [PMID: 33103501 DOI: 10.1080/14728222.2020.1842358] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
INTRODUCTION Multiple sclerosis (MS) is a chronic inflammatory-demyelinating disease of the central nervous system associated with lesions of the cortical gray matter and subcortical white matter. Recently, cortical lesions have become a major focus of research because cortical pathology and neuronal damage are critical determinants of irreversible clinical progression. Recent transcriptomic studies point toward cell type-specific changes in cortical neurons in MS with a selective vulnerability of excitatory projection neuron subtypes. AREAS COVERED We discuss the cortical mapping and the molecular properties of excitatory projection neurons and their role in MS lesion pathology while placing an emphasis on their subtype-specific transcriptomic changes and levels of vulnerability. We also examine the latest magnetic resonance imaging techniques to study cortical MS pathology as a key tool for monitoring disease progression and treatment efficacy. Finally, we consider possible therapeutic avenues and novel strategies to protect excitatory cortical projection neurons. Literature search methodology: PubMed articles from 2000-2020. EXPERT OPINION Excitatory cortical projection neurons are an emerging therapeutic target in the treatment of progressive MS. Understanding neuron subtype-specific molecular pathologies and their exact spatial mapping will help establish starting points for the development of novel cell type-specific therapies and biomarkers in MS.
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Affiliation(s)
- Tatjana Beutel
- Department of Neurology, Medical Faculty Mannheim, MCTN, Heidelberg University , Mannheim, Germany
| | - Julia Dzimiera
- Department of Neurology, Medical Faculty Mannheim, MCTN, Heidelberg University , Mannheim, Germany
| | - Hannah Kapell
- Department of Neurology, Medical Faculty Mannheim, MCTN, Heidelberg University , Mannheim, Germany
| | - Maren Engelhardt
- Institute of Neuroanatomy, Medical Faculty Mannheim, MCTN, Heidelberg University , Mannheim, Germany.,Interdisciplinary Center for Neurosciences, Heidelberg University , Heidelberg, Germany
| | - Achim Gass
- Department of Neurology, Medical Faculty Mannheim, MCTN, Heidelberg University , Mannheim, Germany
| | - Lucas Schirmer
- Department of Neurology, Medical Faculty Mannheim, MCTN, Heidelberg University , Mannheim, Germany.,Interdisciplinary Center for Neurosciences, Heidelberg University , Heidelberg, Germany
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13
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Raftopoulos R, Kuhle J, Grant D, Hickman SJ, Altmann DR, Leppert D, Blennow K, Zetterberg H, Kapoor R, Giovannoni G, Gnanapavan S. Neurofilament results for the phase II neuroprotection study of phenytoin in optic neuritis. Eur J Neurol 2020; 28:587-594. [PMID: 33058438 DOI: 10.1111/ene.14591] [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: 07/08/2020] [Revised: 09/05/2020] [Accepted: 10/08/2020] [Indexed: 11/30/2022]
Abstract
BACKGROUND A randomized trial of phenytoin in acute optic neuritis (ON) demonstrated a 30% reduction in retinal nerve fiber layer (RNFL) loss with phenytoin versus placebo. Here we present the corresponding serum neurofilament analyses. METHODS Eighty-six acute ON cases were randomized to receive phenytoin (4-6 mg/kg/day) or placebo for 3 months, and followed up for 6 months. Serum was collected at baseline, 3 and 6 months for analysis of neurofilament heavy chain (NfH) and neurofilament light chain (NfL). RESULTS Sixty-four patients had blood sampling. Of these, 58 and 56 were available at 3 months, and 55 and 54 were available at 6 months for NfH and NfL, respectively. There was no significant correlation between serum NfH and NfL at the time points tested. For NfH, the difference in mean placebo - phenytoin was -44 pg/ml at 3 months (P = 0.019) and -27 pg/ml at 6 months (P = 0.234). For NfL, the difference was 1.4 pg/ml at 3 months (P = 0.726) and -1.6 pg/ml at 6 months (P = 0.766). CONCLUSIONS At 3 months, there was a reduction in NfH, but not NFL, in the phenytoin versus placebo group, while differences at 6 months were not statistically significant. This suggests a potential neuroprotective role for phenytoin in acute ON, with the lower NfH at 3 months, when levels secondary to degeneration of the anterior visual pathway are still elevated, but not at 6 months, when levels have normalized.
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Affiliation(s)
- R Raftopoulos
- University College London Institute of Neurology, London, UK
| | - J Kuhle
- Department of Neurology, University Hospital Basel, Basel, Switzerland
| | - D Grant
- University College London Institute of Neurology, London, UK
| | - S J Hickman
- Department of Neurology, Royal Hallamshire Hospital, Sheffield, UK
| | - D R Altmann
- Medical Statistics Department, London School of Hygiene & Tropical Medicine, London, UK
| | - D Leppert
- Department of Neurology, University Hospital Basel, Basel, Switzerland
| | - K Blennow
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - H Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden.,Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, Queen Square, London, UK.,UK Dementia Research Institute at UCL, London, UK
| | - R Kapoor
- University College London Institute of Neurology, London, UK
| | - G Giovannoni
- Department of Neuroscience & Trauma, QMUL, London, UK
| | - S Gnanapavan
- Department of Neuroscience & Trauma, QMUL, London, UK
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14
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Park SJ, Choi JW. Brain energy metabolism and multiple sclerosis: progress and prospects. Arch Pharm Res 2020; 43:1017-1030. [PMID: 33119885 DOI: 10.1007/s12272-020-01278-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Accepted: 10/21/2020] [Indexed: 02/07/2023]
Abstract
Multiple sclerosis (MS) is an autoimmune disease accompanied with nerve pain and paralysis. Although various pathogenic causes of MS have been suggested, including genetic and environmental factors, how MS occurs remains unclear. Moreover, MS should be diagnosed based on clinical experiences because of no disease-specific biomarker and currently available treatments for MS just can reduce relapsing frequency or severity with little effects on disease disability. Therefore, more efforts are required to identify pathophysiology of MS and diagnosis markers. Recent evidence indicates another aspect of MS pathogenesis, energy failure in the central nervous system (CNS). For instance, inflammation that is a characteristic MS symptom and occurs frequently in the CNS of MS patients can result into energy failure in mitochondria and cytosol. Indeed, metabolomics studies for MS have reported energy failure in oxidative phosphorylation and alteration of aerobic glycolysis. Therefore, studies on the metabolism in the CNS may provide another insight for understanding complexity of MS and pathogenesis, which would facilitate the discovery of promising strategies for developing therapeutics to treat MS. This review will provide an overview on recent progress of metabolomic studies for MS, with a focus on the fluctuation of energy metabolism in MS.
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Affiliation(s)
- Sung Jean Park
- College of Pharmacy and Gachon Institute of Pharmaceutical Sciences, Gachon University, 191 Hambakmoero, Yeonsu-gu, Incheon, 21936, Korea.
| | - Ji Woong Choi
- College of Pharmacy and Gachon Institute of Pharmaceutical Sciences, Gachon University, 191 Hambakmoero, Yeonsu-gu, Incheon, 21936, Korea.
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15
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Alcover-Sanchez B, Garcia-Martin G, Escudero-Ramirez J, Gonzalez-Riano C, Lorenzo P, Gimenez-Cassina A, Formentini L, de la Villa-Polo P, Pereira MP, Wandosell F, Cubelos B. Absence of R-Ras1 and R-Ras2 causes mitochondrial alterations that trigger axonal degeneration in a hypomyelinating disease model. Glia 2020; 69:619-637. [PMID: 33010069 DOI: 10.1002/glia.23917] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 08/18/2020] [Accepted: 09/21/2020] [Indexed: 12/11/2022]
Abstract
Fast synaptic transmission in vertebrates is critically dependent on myelin for insulation and metabolic support. Myelin is produced by oligodendrocytes (OLs) that maintain multilayered membrane compartments that wrap around axonal fibers. Alterations in myelination can therefore lead to severe pathologies such as multiple sclerosis. Given that hypomyelination disorders have complex etiologies, reproducing clinical symptoms of myelin diseases from a neurological perspective in animal models has been difficult. We recently reported that R-Ras1-/- and/or R-Ras2-/- mice, which lack GTPases essential for OL survival and differentiation processes, present different degrees of hypomyelination in the central nervous system with a compounded hypomyelination in double knockout (DKO) mice. Here, we discovered that the loss of R-Ras1 and/or R-Ras2 function is associated with aberrant myelinated axons with increased numbers of mitochondria, and a disrupted mitochondrial respiration that leads to increased reactive oxygen species levels. Consequently, aberrant myelinated axons are thinner with cytoskeletal phosphorylation patterns typical of axonal degeneration processes, characteristic of myelin diseases. Although we observed different levels of hypomyelination in a single mutant mouse, the combined loss of function in DKO mice lead to a compromised axonal integrity, triggering the loss of visual function. Our findings demonstrate that the loss of R-Ras function reproduces several characteristics of hypomyelinating diseases, and we therefore propose that R-Ras1-/- and R-Ras2-/- neurological models are valuable approaches for the study of these myelin pathologies.
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Affiliation(s)
- Berta Alcover-Sanchez
- Departamento de Biología Molecular and Centro Biología Molecular "Severo Ochoa", Universidad Autónoma de Madrid - Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Gonzalo Garcia-Martin
- Departamento de Biología Molecular and Centro Biología Molecular "Severo Ochoa", Universidad Autónoma de Madrid - Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Juan Escudero-Ramirez
- Departamento de Biología Molecular and Centro Biología Molecular "Severo Ochoa", Universidad Autónoma de Madrid - Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Carolina Gonzalez-Riano
- CEMBIO (Centre for Metabolomics and Bioanalysis), Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Madrid, Spain
| | - Paz Lorenzo
- CEMBIO (Centre for Metabolomics and Bioanalysis), Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Madrid, Spain
| | - Alfredo Gimenez-Cassina
- Departamento de Biología Molecular and Centro Biología Molecular "Severo Ochoa", Universidad Autónoma de Madrid - Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Laura Formentini
- Departamento de Biología Molecular and Centro Biología Molecular "Severo Ochoa", Universidad Autónoma de Madrid - Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Pedro de la Villa-Polo
- Departamento de Biología de Sistemas, Universidad de Alcalá, Madrid, Spain.,Grupo de Neurofisiología Visual, Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), Madrid, Spain
| | - Marta P Pereira
- Departamento de Biología Molecular and Centro Biología Molecular "Severo Ochoa", Universidad Autónoma de Madrid - Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Francisco Wandosell
- Departamento de Biología Molecular and Centro Biología Molecular "Severo Ochoa", Universidad Autónoma de Madrid - Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Beatriz Cubelos
- Departamento de Biología Molecular and Centro Biología Molecular "Severo Ochoa", Universidad Autónoma de Madrid - Consejo Superior de Investigaciones Científicas, Madrid, Spain
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16
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Hnilicová P, Štrbák O, Kolisek M, Kurča E, Zeleňák K, Sivák Š, Kantorová E. Current Methods of Magnetic Resonance for Noninvasive Assessment of Molecular Aspects of Pathoetiology in Multiple Sclerosis. Int J Mol Sci 2020; 21:E6117. [PMID: 32854318 PMCID: PMC7504207 DOI: 10.3390/ijms21176117] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 08/13/2020] [Accepted: 08/21/2020] [Indexed: 12/29/2022] Open
Abstract
Multiple sclerosis (MS) is an autoimmune disease with expanding axonal and neuronal degeneration in the central nervous system leading to motoric dysfunctions, psychical disability, and cognitive impairment during MS progression. The exact cascade of pathological processes (inflammation, demyelination, excitotoxicity, diffuse neuro-axonal degeneration, oxidative and metabolic stress, etc.) causing MS onset is still not fully understood, although several accompanying biomarkers are particularly suitable for the detection of early subclinical changes. Magnetic resonance (MR) methods are generally considered to be the most sensitive diagnostic tools. Their advantages include their noninvasive nature and their ability to image tissue in vivo. In particular, MR spectroscopy (proton 1H and phosphorus 31P MRS) is a powerful analytical tool for the detection and analysis of biomedically relevant metabolites, amino acids, and bioelements, and thus for providing information about neuro-axonal degradation, demyelination, reactive gliosis, mitochondrial and neurotransmitter failure, cellular energetic and membrane alternation, and the imbalance of magnesium homeostasis in specific tissues. Furthermore, the MR relaxometry-based detection of accumulated biogenic iron in the brain tissue is useful in disease evaluation. The early description and understanding of the developing pathological process might be critical for establishing clinically effective MS-modifying therapies.
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Affiliation(s)
- Petra Hnilicová
- Biomedical Center Martin, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 036 01 Martin, Slovakia; (O.Š.); (M.K.)
| | - Oliver Štrbák
- Biomedical Center Martin, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 036 01 Martin, Slovakia; (O.Š.); (M.K.)
| | - Martin Kolisek
- Biomedical Center Martin, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 036 01 Martin, Slovakia; (O.Š.); (M.K.)
| | - Egon Kurča
- Clinic of Neurology, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 036 01 Martin, Slovakia; (E.K.); (Š.S.); (E.K.)
| | - Kamil Zeleňák
- Clinic of Radiology, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 036 01 Martin, Slovakia;
| | - Štefan Sivák
- Clinic of Neurology, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 036 01 Martin, Slovakia; (E.K.); (Š.S.); (E.K.)
| | - Ema Kantorová
- Clinic of Neurology, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 036 01 Martin, Slovakia; (E.K.); (Š.S.); (E.K.)
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17
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Uncini A, Santoro L. The electrophysiology of axonal neuropathies: More than just evidence of axonal loss. Clin Neurophysiol 2020; 131:2367-2374. [PMID: 32828039 DOI: 10.1016/j.clinph.2020.07.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 07/13/2020] [Accepted: 07/22/2020] [Indexed: 11/15/2022]
Abstract
It is common belief that axonal neuropathies are characterized by simple axonal degeneration and loss and that the electrophysiological correlates are just reduced compound muscle action potential and sensory nerve action potential amplitudes with normal or slightly slow conduction velocity. However, axonal autoimmune neuropathies with involvement of the nodal region and axonal neuropathies due to energy restriction such as occurring in nerve ischemia, thiamine deficiency, critical illness, and mitochondrial disorders present conduction failure that can be either reversible with prompt recovery or progress to axonal degeneration with poor outcome. Moreover autoimmune axonal neuropathies due to nodal voltage gated sodium channels dysfunction/disruption may show slowing of conduction velocity, even in the demyelinating range, possibly due to prolongation of the depolarization time required to reach the threshold for action potential regeneration at subsequent nodes. These observations widen the spectrum of the electrophysiological features in some axonal neuropathies, should be taken into account to avoid misdiagnoses and for correct prognostication, and should stimulate the quest of timely targeted treatments that can eventually halt the progression from conduction failure to axonal degeneration.
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Affiliation(s)
- Antonino Uncini
- Department of Neuroscience, Imaging and Clinical Sciences, University "G. d'Annunzio", 66100 Chieti-Pescara, Italy.
| | - Lucio Santoro
- Department of Neurosciences, Reproductive Sciences and Odontostomatology, University of Naples "Federico II", Naples, Italy
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18
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Trinh T, Park SB, Murray J, Pickering H, Lin CSY, Martin A, Friedlander M, Kiernan MC, Goldstein D, Krishnan AV. Neu-horizons: neuroprotection and therapeutic use of riluzole for the prevention of oxaliplatin-induced neuropathy-a randomised controlled trial. Support Care Cancer 2020; 29:1103-1110. [PMID: 32607598 DOI: 10.1007/s00520-020-05591-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Accepted: 06/23/2020] [Indexed: 12/22/2022]
Abstract
TRIAL DESIGN Peripheral neuropathy is a commonly reported adverse effect of oxaliplatin treatment, representing a significant limitation which may require discontinuation of effective therapy. The present study investigated the neuroprotective potential of riluzole in patients undergoing oxaliplatin treatment in a randomised-controlled trial comparing riluzole and placebo-control. METHODS Fifty-two patients (17 females, 58.1 ± 12.7 years) receiving oxaliplatin treatment were randomised into either a treatment (50 mg riluzole) or lactose placebo group. The primary outcome measure was the total neuropathy score-reduced (TNSr). Secondary outcome measures include nerve excitability measures, 9-hole pegboard and FACT-GOG NTX questionnaire. Patients were assessed at baseline, pre-cycle 10 or 12, 4-week and 12-week post-treatment. RESULTS Both the treatment and placebo groups developed objective and patient reported evidence of neurotoxicity over the course of oxaliplatin treatment, although there were no significant differences across any parameters between the two groups. However, across follow-up assessments, the treatment group experienced greater neuropathy, represented by a higher TNSr score at 4-week post-chemotherapy of 8.3 ± 2.7 compared with 4.6 ± 3.6 (p = 0.032) which was sustained at 12-week post-treatment (p = 0.089). Similarly, patients in the treatment group reported worse symptoms with a FACT-GOG NTX score of 37.4 ± 10.2 compared with 43.3 ± 7.4 (p = 0.02) in the placebo group at 4-week post-treatment. CONCLUSION This study is the first to provide an objective clinical investigation of riluzole in oxaliplatin-induced peripheral neuropathy employing both functional and neurophysiological measures. Although the recruitment target was not reached, the results do not show any benefit of riluzole in minimising neuropathy and may suggest that riluzole worsens neuropathy associated with oxaliplatin treatment.
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Affiliation(s)
- Terry Trinh
- Prince of Wales Clinical School, University of New South Wales, Sydney, Australia
| | - Susanna B Park
- Brain and Mind Centre, University of Sydney, Sydney, Australia
| | - Jenna Murray
- Prince of Wales Clinical School, University of New South Wales, Sydney, Australia
| | - Hannah Pickering
- Prince of Wales Clinical School, University of New South Wales, Sydney, Australia
| | - Cindy S-Y Lin
- Brain and Mind Centre, University of Sydney, Sydney, Australia
| | - Andrew Martin
- National Health and Medical Research Centre Clinical Trials Centre, University of Sydney, Sydney, Australia
| | - Michael Friedlander
- Department of Medical Oncology, Prince of Wales Hospital, Randwick, Sydney, Australia
| | | | - David Goldstein
- Prince of Wales Clinical School, University of New South Wales, Sydney, Australia.,Department of Medical Oncology, Prince of Wales Hospital, Randwick, Sydney, Australia
| | - Arun V Krishnan
- Prince of Wales Clinical School, University of New South Wales, Sydney, Australia. .,Department of Neurological Sciences, Prince of Wales Hospital, Level 2 High Street, Randwick, Sydney, NSW, 2031, Australia.
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19
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Warnock A, Toomey LM, Wright AJ, Fisher K, Won Y, Anyaegbu C, Fitzgerald M. Damage Mechanisms to Oligodendrocytes and White Matter in Central Nervous System Injury: The Australian Context. J Neurotrauma 2020; 37:739-769. [DOI: 10.1089/neu.2019.6890] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- Andrew Warnock
- Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia, Australia
| | - Lillian M. Toomey
- Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia, Australia
- Perron Institute for Neurological and Translational Science, Nedlands, Western Australia, Australia
| | - Alexander J. Wright
- Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia, Australia
| | - Katherine Fisher
- School of Human Sciences, The University of Western Australia, Perth, Western Australia, Australia
| | - Yerim Won
- School of Human Sciences, The University of Western Australia, Perth, Western Australia, Australia
| | - Chidozie Anyaegbu
- Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia, Australia
| | - Melinda Fitzgerald
- Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia, Australia
- Perron Institute for Neurological and Translational Science, Nedlands, Western Australia, Australia
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20
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Alrashdi B, Dawod B, Schampel A, Tacke S, Kuerten S, Marshall JS, Côté PD. Nav1.6 promotes inflammation and neuronal degeneration in a mouse model of multiple sclerosis. J Neuroinflammation 2019; 16:215. [PMID: 31722722 PMCID: PMC6852902 DOI: 10.1186/s12974-019-1622-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 10/22/2019] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND In multiple sclerosis (MS) and in the experimental autoimmune encephalomyelitis (EAE) model of MS, the Nav1.6 voltage-gated sodium (Nav) channel isoform has been implicated as a primary contributor to axonal degeneration. Following demyelination Nav1.6, which is normally co-localized with the Na+/Ca2+ exchanger (NCX) at the nodes of Ranvier, associates with β-APP, a marker of neural injury. The persistent influx of sodium through Nav1.6 is believed to reverse the function of NCX, resulting in an increased influx of damaging Ca2+ ions. However, direct evidence for the role of Nav1.6 in axonal degeneration is lacking. METHODS In mice floxed for Scn8a, the gene that encodes the α subunit of Nav1.6, subjected to EAE we examined the effect of eliminating Nav1.6 from retinal ganglion cells (RGC) in one eye using an AAV vector harboring Cre and GFP, while using the contralateral either injected with AAV vector harboring GFP alone or non-targeted eye as control. RESULTS In retinas, the expression of Rbpms, a marker for retinal ganglion cells, was found to be inversely correlated to the expression of Scn8a. Furthermore, the gene expression of the pro-inflammatory cytokines Il6 (IL-6) and Ifng (IFN-γ), and of the reactive gliosis marker Gfap (GFAP) were found to be reduced in targeted retinas. Optic nerves from targeted eyes were shown to have reduced macrophage infiltration and improved axonal health. CONCLUSION Taken together, our results are consistent with Nav1.6 promoting inflammation and contributing to axonal degeneration following demyelination.
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Affiliation(s)
- Barakat Alrashdi
- Department of Biology, Dalhousie University, Halifax, NS, B3H 4R2, Canada.,Department of Biology, Al-Jouf University, Sakaka, Saudi Arabia
| | - Bassel Dawod
- Department of Pathology, Dalhousie University, Halifax, NS, B3H 4R2, Canada
| | - Andrea Schampel
- Institute of Anatomy and Cell Biology Friedrich Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Sabine Tacke
- Institute of Anatomy and Cell Biology Friedrich Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Stefanie Kuerten
- Institute of Anatomy and Cell Biology Friedrich Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany
| | - Jean S Marshall
- Department of Pathology, Dalhousie University, Halifax, NS, B3H 4R2, Canada.,Department of Microbiology and Immunology, Dalhousie University, Halifax, NS, B3H 4R2, Canada
| | - Patrice D Côté
- Department of Biology, Dalhousie University, Halifax, NS, B3H 4R2, Canada. .,Department of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, NS, B3H 4R2, Canada.
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21
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Witte ME, Schumacher AM, Mahler CF, Bewersdorf JP, Lehmitz J, Scheiter A, Sánchez P, Williams PR, Griesbeck O, Naumann R, Misgeld T, Kerschensteiner M. Calcium Influx through Plasma-Membrane Nanoruptures Drives Axon Degeneration in a Model of Multiple Sclerosis. Neuron 2019; 101:615-624.e5. [PMID: 30686733 PMCID: PMC6389591 DOI: 10.1016/j.neuron.2018.12.023] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 11/09/2018] [Accepted: 12/12/2018] [Indexed: 11/15/2022]
Abstract
Axon loss determines persistent disability in multiple sclerosis patients. Here, we use in vivo calcium imaging in a multiple sclerosis model to show that cytoplasmic calcium levels determine the choice between axon loss and survival. We rule out the endoplasmic reticulum, glutamate excitotoxicity, and the reversal of the sodium-calcium exchanger as sources of intra-axonal calcium accumulation and instead identify nanoscale ruptures of the axonal plasma membrane as the critical path of calcium entry.
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Affiliation(s)
- Maarten E Witte
- Institute of Clinical Neuroimmunology, University Hospital, Ludwig-Maximilians Universität München, Marchioninistraße 15, 81377 Munich, Germany; Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians Universität München, Großhaderner Strasse 9, 82152 Planegg Martinsried, Germany
| | - Adrian-Minh Schumacher
- Institute of Clinical Neuroimmunology, University Hospital, Ludwig-Maximilians Universität München, Marchioninistraße 15, 81377 Munich, Germany; Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians Universität München, Großhaderner Strasse 9, 82152 Planegg Martinsried, Germany
| | - Christoph F Mahler
- Institute of Clinical Neuroimmunology, University Hospital, Ludwig-Maximilians Universität München, Marchioninistraße 15, 81377 Munich, Germany; Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians Universität München, Großhaderner Strasse 9, 82152 Planegg Martinsried, Germany
| | - Jan P Bewersdorf
- Institute of Clinical Neuroimmunology, University Hospital, Ludwig-Maximilians Universität München, Marchioninistraße 15, 81377 Munich, Germany; Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians Universität München, Großhaderner Strasse 9, 82152 Planegg Martinsried, Germany
| | - Jonas Lehmitz
- Institute of Clinical Neuroimmunology, University Hospital, Ludwig-Maximilians Universität München, Marchioninistraße 15, 81377 Munich, Germany; Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians Universität München, Großhaderner Strasse 9, 82152 Planegg Martinsried, Germany; Institute of Neuronal Cell Biology, Technische Universität München, Biedersteiner Straße 29, 80802 Munich, Germany
| | - Alexander Scheiter
- Institute of Clinical Neuroimmunology, University Hospital, Ludwig-Maximilians Universität München, Marchioninistraße 15, 81377 Munich, Germany; Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians Universität München, Großhaderner Strasse 9, 82152 Planegg Martinsried, Germany; Institute of Neuronal Cell Biology, Technische Universität München, Biedersteiner Straße 29, 80802 Munich, Germany
| | - Paula Sánchez
- Institute of Clinical Neuroimmunology, University Hospital, Ludwig-Maximilians Universität München, Marchioninistraße 15, 81377 Munich, Germany; Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians Universität München, Großhaderner Strasse 9, 82152 Planegg Martinsried, Germany
| | - Philip R Williams
- Institute of Neuronal Cell Biology, Technische Universität München, Biedersteiner Straße 29, 80802 Munich, Germany
| | - Oliver Griesbeck
- Max-Planck Institute of Neurobiology, Am Klopferspitz 18, 82152 Planegg-Martinsried, Germany
| | - Ronald Naumann
- Max-Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Thomas Misgeld
- Institute of Neuronal Cell Biology, Technische Universität München, Biedersteiner Straße 29, 80802 Munich, Germany; Munich Cluster for Systems Neurology (SyNergy), Feodor-Lynen-Straße 17, 81377 Munich, Germany; German Center for Neurodegenerative Diseases (DZNE), Feodor-Lynen-Straße 17, 81377 Munich, Germany; Center of Integrated Protein Science (CIPSM), Butenandtstraße 5-13, 81377 Munich, Germany.
| | - Martin Kerschensteiner
- Institute of Clinical Neuroimmunology, University Hospital, Ludwig-Maximilians Universität München, Marchioninistraße 15, 81377 Munich, Germany; Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians Universität München, Großhaderner Strasse 9, 82152 Planegg Martinsried, Germany; Munich Cluster for Systems Neurology (SyNergy), Feodor-Lynen-Straße 17, 81377 Munich, Germany.
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Physiology of Myelinated Nerve Conduction and Pathophysiology of Demyelination. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1190:85-106. [DOI: 10.1007/978-981-32-9636-7_7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Petersen ER, Søndergaard HB, Laursen JH, Olsson AG, Börnsen L, Soelberg Sørensen P, Sellebjerg F, Bang Oturai A. Smoking is associated with increased disease activity during natalizumab treatment in multiple sclerosis. Mult Scler 2018; 25:1298-1305. [DOI: 10.1177/1352458518791753] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Background: Smoking has been associated with increased multiple sclerosis (MS) risk, disease worsening, and progression in MS patients. Furthermore, interactions between smoking and human leukocyte antigen (HLA) genes have been shown for MS risk. Recently, we found that smoking was associated with an increased relapse rate in interferon-beta-treated relapsing-remitting multiple sclerosis (RRMS) patients. Objectives: We examined the association between smoking and relapses in natalizumab-treated RRMS patients. Second, we investigated if an interaction between smoking and HLA-DRB1*15:01 or HLA-A*02:01 affected the number of relapses during treatment. Methods: In this observational cohort study, 355 natalizumab-treated RRMS patients were assessed. Prespecified criteria excluded 62 patients. Clinical data from the starting of treatment to the two-year follow-up visit were collected. Smoking status was obtained by a questionnaire survey. TaqMan allelic discrimination was used for genotyping of tag single-nucleotide polymorphisms (SNPs) for HLA-DRB1*15:01 and HLA-A*02:01. Negative binomial regression analysis was used to analyze the association between relapse rate and smoking intensity and HLA. Results: One pack of cigarettes (20 cigarettes) per day during natalizumab treatment increased the relapse rate during treatment with 38% (incidence rate ratio (IRR) = 1.38, 95% confidence interval (CI): 1.08–1.77, p = 0.01). No association or interaction was found between smoking and HLA-DRB1*15:01 or HLA-A*02:01, respectively. Conclusion: Smoking intensity was significantly associated with the number of relapses during natalizumab treatment.
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Affiliation(s)
- Eva Rosa Petersen
- Danish Multiple Sclerosis Center, Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Helle Bach Søndergaard
- Danish Multiple Sclerosis Center, Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Julie Hejgaard Laursen
- Danish Multiple Sclerosis Center, Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Anna Gabriella Olsson
- Danish Multiple Sclerosis Center, Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Lars Börnsen
- Danish Multiple Sclerosis Center, Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Per Soelberg Sørensen
- Danish Multiple Sclerosis Center, Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Finn Sellebjerg
- Danish Multiple Sclerosis Center, Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Annette Bang Oturai
- Danish Multiple Sclerosis Center, Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
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24
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Ingwersen J, De Santi L, Wingerath B, Graf J, Koop B, Schneider R, Hecker C, Schröter F, Bayer M, Engelke AD, Dietrich M, Albrecht P, Hartung HP, Annunziata P, Aktas O, Prozorovski T. Nimodipine confers clinical improvement in two models of experimental autoimmune encephalomyelitis. J Neurochem 2018; 146:86-98. [PMID: 29473171 DOI: 10.1111/jnc.14324] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 02/07/2018] [Accepted: 02/08/2018] [Indexed: 12/31/2022]
Abstract
Multiple sclerosis is characterised by inflammatory neurodegeneration, with axonal injury and neuronal cell death occurring in parallel to demyelination. Regarding the molecular mechanisms responsible for demyelination and axonopathy, energy failure, aberrant expression of ion channels and excitotoxicity have been suggested to lead to Ca2+ overload and subsequent activation of calcium-dependent damage pathways. Thus, the inhibition of Ca2+ influx by pharmacological modulation of Ca2+ channels may represent a novel neuroprotective strategy in the treatment of secondary axonopathy. We therefore investigated the effects of the L-type voltage-gated calcium channel blocker nimodipine in two different models of mouse experimental autoimmune encephalomyelitis (EAE), an established experimental paradigm for multiple sclerosis. We show that preventive application of nimodipine (10 mg/kg per day) starting on the day of induction had ameliorating effects on EAE in SJL/J mice immunised with encephalitic myelin peptide PLP139-151 , specifically in late-stage disease. Furthermore, supporting these data, administration of nimodipine to MOG35-55 -immunised C57BL/6 mice starting at the peak of pre-established disease, also led to a significant decrease in disease score, indicating a protective effect on secondary CNS damage. Histological analysis confirmed that nimodipine attenuated demyelination, axonal loss and pathological axonal β-amyloid precursor protein accumulation in the cerebellum and spinal cord in the chronic phase of disease. Of note, we observed no effects of nimodipine on the peripheral immune response in EAE mice with regard to distribution, antigen-specific proliferation or activation patterns of lymphocytes. Taken together, our data suggest a CNS-specific effect of L-type voltage-gated calcium channel blockade to inflammation-induced neurodegeneration.
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Affiliation(s)
- Jens Ingwersen
- Department of Neurology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Lorenzo De Santi
- Department of Neurology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
- Department of Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy
| | - Britta Wingerath
- Department of Neurology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Jonas Graf
- Department of Neurology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Barbara Koop
- Department of Neurology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Reiner Schneider
- Department of Neurology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Christina Hecker
- Department of Neurology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Friederike Schröter
- Department of Neurology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Mary Bayer
- Department of Neurology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Anna Dorothee Engelke
- Department of Neurology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Michael Dietrich
- Department of Neurology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Philipp Albrecht
- Department of Neurology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Hans-Peter Hartung
- Department of Neurology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Pasquale Annunziata
- Department of Medicine, Surgery and Neuroscience, University of Siena, Siena, Italy
| | - Orhan Aktas
- Department of Neurology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Tim Prozorovski
- Department of Neurology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
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25
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Adiele RC, Adiele CA. Metabolic defects in multiple sclerosis. Mitochondrion 2017; 44:7-14. [PMID: 29246870 DOI: 10.1016/j.mito.2017.12.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 10/12/2017] [Accepted: 12/11/2017] [Indexed: 02/07/2023]
Abstract
Brain injuries in multiple sclerosis (MS) involve immunopathological, structural and metabolic defects on myelin sheath, oligodendrocytes (OLs), axons and neurons suggesting that different cellular mechanisms ultimately result in the formation of MS plaques, demyelination, inflammation and brain damage. Bioenergetics, oxygen and ion metabolism dominate the metabolic and biochemical pathways that maintain neuronal viability and impulse transmission which directly or indirectly point to mitochondrial integrity and adenosine triphosphate (ATP) availability indicating the involvement of mitochondria in the pathogenesis of MS. Loss of myelin proteins including myelin basic protein (MBP), proteolipid protein (PLP), myelin associated glycoprotein (MAG), myelin oligodendrocyte glycoproetin (MOG), 2, 3,-cyclic nucleotide phosphodiestarase (CNPase); microglia and microphage activation, oligodendrocyte apoptosis as well as expression of inducible nitric oxide synthase (i-NOS) and myeloperoxidase activities have been implicated in a subset of Balo's type and relapsing remitting MS (RRMS) lesions indicating the involvement of metabolic defects and oxidative stress in MS. Here, we provide an insighting review of defects in cellular metabolism including energy, oxygen and metal metabolism in MS as well as the relevance of animal models of MS in understanding the molecular, biochemical and cellular mechanisms of MS pathogenesis. Additionally, we also discussed the potential for mitochondrial targets and antioxidant protection for therapeutic benefits in MS.
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Affiliation(s)
- Reginald C Adiele
- Department of Anatomy and Cell Biology, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada; Cameco MS Neuroscience Research Center, Saskatoon City Hospital, Saskatoon, SK, Canada; Department of Public Health, Concordia University of Edmonton, Edmonton, AB, Canada.
| | - Chiedukam A Adiele
- Department of Clinical Pharmacy, Faculty of Pharmaceutical Sciences, University of Nigeria, Nsukka, Nigeria
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26
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Abstract
Increasing evidence suggests a key role for tissue energy failure in the pathophysiology of multiple sclerosis (MS). Studies in experimental autoimmune encephalomyelitis (EAE), a commonly used model of MS, have been instrumental in illuminating the mechanisms that may be involved in compromising energy production. In this article, we review recent advances in EAE research focussing on factors that conspire to impair tissue energy metabolism, such as tissue hypoxia, mitochondrial dysfunction, production of reactive oxygen/nitrogen species, and sodium dysregulation, which are directly affected by energy insufficiency, and promote cellular damage. A greater understanding of how inflammation affects tissue energy balance may lead to novel and effective therapeutic strategies that ultimately will benefit not only people affected by MS but also people affected by the wide range of other neurological disorders in which neuroinflammation plays an important role.
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Affiliation(s)
- Roshni A Desai
- Department of Neuroinflammation, UCL Institute of Neurology, London, UK
| | - Kenneth J Smith
- Department of Neuroinflammation, UCL Institute of Neurology, London, UK
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27
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Kovalchuk MO, Franssen H, Van Schelven LJ, Sleutjes BTHM. Comparing excitability at 37°C versus at 20°C: Differences between motor and sensory axons. Muscle Nerve 2017; 57:574-580. [DOI: 10.1002/mus.25960] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/02/2017] [Indexed: 11/06/2022]
Affiliation(s)
- Maria O. Kovalchuk
- Department of Neurology and Neurosurgery, Brain Center Rudolf MagnusUniversity Medical Center UtrechtUtrecht The Netherlands
| | - Hessel Franssen
- Department of Neurology and Neurosurgery, Brain Center Rudolf MagnusUniversity Medical Center UtrechtUtrecht The Netherlands
| | - Leonard J. Van Schelven
- Department of Medical Technology and Clinical PhysicsUniversity Medical Center UtrechtUtrecht the Netherlands
| | - Boudewijn T. H. M. Sleutjes
- Department of Neurology and Neurosurgery, Brain Center Rudolf MagnusUniversity Medical Center UtrechtUtrecht The Netherlands
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28
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Sarkar P, Redondo J, Kemp K, Ginty M, Wilkins A, Scolding NJ, Rice CM. Reduced neuroprotective potential of the mesenchymal stromal cell secretome with ex vivo expansion, age and progressive multiple sclerosis. Cytotherapy 2017; 20:21-28. [PMID: 28917625 PMCID: PMC5758344 DOI: 10.1016/j.jcyt.2017.08.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2017] [Revised: 08/09/2017] [Accepted: 08/10/2017] [Indexed: 12/24/2022]
Abstract
BACKGROUND Clinical trials using ex vivo expansion of autologous mesenchymal stromal cells (MSCs) are in progress for several neurological diseases including multiple sclerosis (MS). Given that environment alters MSC function, we examined whether in vitro expansion, increasing donor age and progressive MS affect the neuroprotective properties of the MSC secretome. METHODS Comparative analyses of neuronal survival in the presence of MSC-conditioned medium (MSCcm) isolated from control subjects (C-MSCcm) and those with MS (MS-MSCcm) were performed following (1) trophic factor withdrawal and (2) nitric oxide-induced neurotoxicity. RESULTS Reduced neuronal survival following trophic factor withdrawal was seen in association with increasing expansion of MSCs in vitro and MSC donor age. Controlling for these factors, there was an independent, negative effect of progressive MS. In nitric oxide neurotoxicity, MSCcm-mediated neuroprotection was reduced when C-MSCcm was isolated from higher-passage MSCs and was negatively associated with increasing MSC passage number and donor age. Furthermore, the neuroprotective effect of MSCcm was lost when MSCs were isolated from patients with MS. DISCUSSION Our findings have significant implications for MSC-based therapy in neurodegenerative conditions, particularly for autologous MSC therapy in MS. Impaired neuroprotection mediated by the MSC secretome in progressive MS may reflect reduced reparative potential of autologous MSC-based therapy in MS and it is likely that the causes must be addressed before the full potential of MSC-based therapy is realized. Additionally, we anticipate that understanding the mechanisms responsible will contribute new insights into MS pathogenesis and may also be of wider relevance to other neurodegenerative conditions.
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Affiliation(s)
- Pamela Sarkar
- School of Clinical Sciences, University of Bristol, Bristol, UK
| | - Juliana Redondo
- School of Clinical Sciences, University of Bristol, Bristol, UK
| | - Kevin Kemp
- School of Clinical Sciences, University of Bristol, Bristol, UK
| | - Mark Ginty
- School of Clinical Sciences, University of Bristol, Bristol, UK
| | | | - Neil J Scolding
- School of Clinical Sciences, University of Bristol, Bristol, UK
| | - Claire M Rice
- School of Clinical Sciences, University of Bristol, Bristol, UK.
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Nandoskar A, Raffel J, Scalfari AS, Friede T, Nicholas RS. Pharmacological Approaches to the Management of Secondary Progressive Multiple Sclerosis. Drugs 2017; 77:885-910. [PMID: 28429241 DOI: 10.1007/s40265-017-0726-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
It is well recognised that the majority of the impact of multiple sclerosis (MS), both personal and societal, arises in the progressive phase where disability accumulates inexorably. As such, progressive MS (PMS) has been the target of pharmacological therapies for many years. However, there are no current licensed treatments for PMS. This stands in marked contrast to relapsing remitting MS (RRMS) where trials have resulted in numerous licensed therapies. PMS has proven to be a more difficult challenge compared to RRMS and this review focuses on secondary progressive MS (SPMS), where relapses occur before the onset of gradual, irreversible disability, and not primary progressive MS where disability accumulation occurs without prior relapses. Although there are similarities between the two forms, in both cases pinpointing when PMS starts is difficult in a condition in which disability can vary from day to day. There is also an overlap between the pathology of relapsing and progressive MS and this has contributed to the lack of well-defined outcomes, both surrogates and clinically relevant outcomes in PMS. In this review, we used the search term 'randomised controlled clinical drug trials in secondary progressive MS' in publications since 1988 together with recently completed trials where results were available. We found 34 trials involving 21 different molecules, of which 38% were successful in reaching their primary outcome. In general, the trials were well designed (e.g. double blind) with sample sizes ranging from 35 to 1949 subjects. The majority were parallel group, but there were also multi-arm and multidose trials as well as the more recent use of adaptive designs. The disability outcome most commonly used was the Expanded Disability Status Scale (EDSS) in all phases, but also magnetic resonance imaging (MRI)-measured brain atrophy has been utilised as a surrogate endpoint in phase II studies. The majority of the treatments tested in SPMS over the years were initially successful in RRMS. This has a number of implications in terms of targeting SPMS, but principally implies that the optimal strategy to target SPMS is to utilise the prodrome of relapses to initiate a therapy that will aim to both prevent progression and slow its accumulation. This approach is in agreement with the early targeting of MS but requires treatments that are both effective and safe if it is to be used before disability is a major problem. Recent successes will hopefully result in the first licensed therapy for PMS and enable us to test this approach.
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Affiliation(s)
- A Nandoskar
- Wolfson Neuroscience Laboratories, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, 160 Du Cane Road, London, W12 0NN, UK
| | - J Raffel
- Wolfson Neuroscience Laboratories, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, 160 Du Cane Road, London, W12 0NN, UK
| | - A S Scalfari
- Wolfson Neuroscience Laboratories, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, 160 Du Cane Road, London, W12 0NN, UK
| | - T Friede
- Department of Medical Statistics, University Medical Center Göttingen, Humboltallee 32, 37073, Göttingen, Germany
| | - R S Nicholas
- Wolfson Neuroscience Laboratories, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, 160 Du Cane Road, London, W12 0NN, UK.
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30
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Kanagaratnam M, Pendleton C, Souza DA, Pettit J, Howells J, Baker MD. Diuretic-sensitive electroneutral Na + movement and temperature effects on central axons. J Physiol 2017; 595:3471-3482. [PMID: 28213919 PMCID: PMC5451713 DOI: 10.1113/jp273963] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 02/13/2017] [Indexed: 01/26/2023] Open
Abstract
Key points Optic nerve axons get less excitable with warming. F‐fibre latency does not shorten at temperatures above 30°C. Action potential amplitude falls when the Na+‐pump is blocked, an effect speeded by warming. Diuretics reduce the rate of action potential fall in the presence of ouabain. Our data are consistent with electroneutral entry of Na+ occurring in axons and contributing to setting the resting potential.
Abstract Raising the temperature of optic nerve from room temperature to near physiological has effects on the threshold, refractoriness and superexcitability of the shortest latency (fast, F) nerve fibres, consistent with hyperpolarization. The temperature dependence of peak impulse latency was weakened at temperatures above 30°C suggesting a temperature‐sensitive process that slows impulse propagation. The amplitude of the supramaximal compound action potential gets larger on warming, whereas in the presence of bumetanide and amiloride (blockers of electroneutral Na+ movement), the action potential amplitude consistently falls. This suggests a warming‐induced hyperpolarization that is reduced by blocking electroneutral Na+ movement. In the presence of ouabain, the action potential collapses. This collapse is speeded by warming, and exposure to bumetanide and amiloride slows the temperature‐dependent amplitude decline, consistent with a warming‐induced increase in electroneutral Na+ entry. Blocking electroneutral Na+ movement is predicted to be useful in the treatment of temperature‐dependent symptoms under conditions with reduced safety factor (Uhthoff's phenomenon) and provide a route to neuroprotection. Optic nerve axons get less excitable with warming. F‐fibre latency does not shorten at temperatures above 30°C. Action potential amplitude falls when the Na+‐pump is blocked, an effect speeded by warming. Diuretics reduce the rate of action potential fall in the presence of ouabain. Our data are consistent with electroneutral entry of Na+ occurring in axons and contributing to setting the resting potential.
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Affiliation(s)
- Meneka Kanagaratnam
- Neuroscience and Trauma centre, Blizard Institute, Queen Mary University of London, 4 Newark Street, Whitechapel, London, E1 2AT, UK
| | - Christopher Pendleton
- Neuroscience and Trauma centre, Blizard Institute, Queen Mary University of London, 4 Newark Street, Whitechapel, London, E1 2AT, UK
| | - Danilo Almeida Souza
- Neuroscience and Trauma centre, Blizard Institute, Queen Mary University of London, 4 Newark Street, Whitechapel, London, E1 2AT, UK
| | - Joseph Pettit
- Neuroscience and Trauma centre, Blizard Institute, Queen Mary University of London, 4 Newark Street, Whitechapel, London, E1 2AT, UK
| | - James Howells
- Brain and Mind Research Institute, University of Sydney, 94 Mallet Street, Camperdown, NSW, 2050, Australia
| | - Mark D Baker
- Neuroscience and Trauma centre, Blizard Institute, Queen Mary University of London, 4 Newark Street, Whitechapel, London, E1 2AT, UK
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31
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Sodium Channels, Mitochondria, and Axonal Degeneration in Peripheral Neuropathy. Trends Mol Med 2016; 22:377-390. [DOI: 10.1016/j.molmed.2016.03.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 03/21/2016] [Accepted: 03/22/2016] [Indexed: 12/19/2022]
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32
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Warne J, Pryce G, Hill JM, Shi X, Lennerås F, Puentes F, Kip M, Hilditch L, Walker P, Simone MI, Chan AWE, Towers GJ, Coker AR, Duchen MR, Szabadkai G, Baker D, Selwood DL. Selective Inhibition of the Mitochondrial Permeability Transition Pore Protects against Neurodegeneration in Experimental Multiple Sclerosis. J Biol Chem 2016; 291:4356-73. [PMID: 26679998 PMCID: PMC4813465 DOI: 10.1074/jbc.m115.700385] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Revised: 12/09/2015] [Indexed: 12/23/2022] Open
Abstract
The mitochondrial permeability transition pore is a recognized drug target for neurodegenerative conditions such as multiple sclerosis and for ischemia-reperfusion injury in the brain and heart. The peptidylprolyl isomerase, cyclophilin D (CypD, PPIF), is a positive regulator of the pore, and genetic down-regulation or knock-out improves outcomes in disease models. Current inhibitors of peptidylprolyl isomerases show no selectivity between the tightly conserved cyclophilin paralogs and exhibit significant off-target effects, immunosuppression, and toxicity. We therefore designed and synthesized a new mitochondrially targeted CypD inhibitor, JW47, using a quinolinium cation tethered to cyclosporine. X-ray analysis was used to validate the design concept, and biological evaluation revealed selective cellular inhibition of CypD and the permeability transition pore with reduced cellular toxicity compared with cyclosporine. In an experimental autoimmune encephalomyelitis disease model of neurodegeneration in multiple sclerosis, JW47 demonstrated significant protection of axons and improved motor assessments with minimal immunosuppression. These findings suggest that selective CypD inhibition may represent a viable therapeutic strategy for MS and identify quinolinium as a mitochondrial targeting group for in vivo use.
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Affiliation(s)
- Justin Warne
- From the Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Gareth Pryce
- From the Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, United Kingdom, the Neuroimmunology Unit, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, 4 Newark Street, London E1 2AT, United Kingdom
| | - Julia M Hill
- the Department of Cell and Developmental Biology, University College London, London WC1E 6BT, United Kingdom
| | - Xiao Shi
- From the Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Felicia Lennerås
- the Neuroimmunology Unit, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, 4 Newark Street, London E1 2AT, United Kingdom
| | - Fabiola Puentes
- the Neuroimmunology Unit, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, 4 Newark Street, London E1 2AT, United Kingdom
| | - Maarten Kip
- From the Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Laura Hilditch
- the Medical Research Council Centre for Medical Molecular Biology, Division of Infection and Immunity, University College London, London WC1E 6BT, United Kingdom
| | - Paul Walker
- Cyprotex Discovery Ltd., 100 Barbirolli Square, Manchester M2 3AB, United Kingdom, and
| | - Michela I Simone
- From the Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - A W Edith Chan
- From the Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Greg J Towers
- the Medical Research Council Centre for Medical Molecular Biology, Division of Infection and Immunity, University College London, London WC1E 6BT, United Kingdom
| | - Alun R Coker
- From the Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Michael R Duchen
- the Department of Cell and Developmental Biology, University College London, London WC1E 6BT, United Kingdom
| | - Gyorgy Szabadkai
- the Department of Cell and Developmental Biology, University College London, London WC1E 6BT, United Kingdom, the Department of Biomedical Sciences, University of Padua, Padua 35122, Italy
| | - David Baker
- the Neuroimmunology Unit, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, 4 Newark Street, London E1 2AT, United Kingdom,
| | - David L Selwood
- From the Wolfson Institute for Biomedical Research, University College London, Gower Street, London WC1E 6BT, United Kingdom,
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Paramanathan S, Tankisi H, Andersen H, Fuglsang-Frederiksen A. Axonal loss in patients with inflammatory demyelinating polyneuropathy as determined by motor unit number estimation and MUNIX. Clin Neurophysiol 2016; 127:898-904. [DOI: 10.1016/j.clinph.2015.05.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 04/29/2015] [Accepted: 05/02/2015] [Indexed: 12/14/2022]
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Flecainide in Amyotrophic Lateral Sclerosis as a Neuroprotective Strategy (FANS): A Randomized Placebo-Controlled Trial. EBioMedicine 2015; 2:1916-22. [PMID: 26844270 PMCID: PMC4703720 DOI: 10.1016/j.ebiom.2015.11.022] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 11/09/2015] [Accepted: 11/11/2015] [Indexed: 12/03/2022] Open
Abstract
Background Abnormalities in membrane excitability and Na+ channel function are characteristic of amyotrophic lateral sclerosis (ALS). We aimed to examine the neuroprotective potential, safety and tolerability of the Na+ channel blocker and membrane stabiliser flecainide in ALS. Methods A double-blind, placebo-controlled, randomised clinical trial of flecainide (200 mg/day) for 32-weeks with a 12-week lead-in phase was conducted in participants with probable or definite ALS recruited from multiple Australian centres (ANZCT Registry number ACTRN12608000338369). Patients were reviewed by a cardiologist to rule out cardiac contraindications. Participants were randomly assigned (1:1) to flecainide or placebo using stratified permuted blocks by a central pharmacy. The primary outcome measure was the slope of decline of the ALS Functional Rating Scale-revised (ALS FRS-r) during the treatment period. Findings Between March 11, 2008 and July 1, 2010, 67 patients were screened, 54 of whom were randomly assigned to receive flecainide (26 patients) or placebo (28 patients). Four patients in the flecainide group and three patients in the placebo group withdrew from the study. One patient in the flecainide group died during the study, attributed to disease progression. Flecainide was generally well tolerated, with no serious adverse events reported in either group. There was no significant difference in the rate of decline in the primary outcome measure ALS-FRS-r between placebo and flecainide treated patients (Flecainide 0.65 [95% CI 0.49 to 0.98]; Placebo 0.81 [0.49 to 2.12] P = 0.50). However, the rate of decline of the neurophysiological index was significantly reduced in the flecainide group (Flecainide 0.06 [0.01 to 0.11]; Placebo 0.14 [0.09 to 0.19], P = 0.02). Placebo-treated patients demonstrated greater CMAP amplitude reduction during the course of the study in the subset of patients with a reduced baseline CMAP amplitude (Flecainide: − 15 ± 12%; Placebo − 59 ± 12%; P = 0.03). Flecainide-treated patients maintained stabilized peripheral axonal excitability over the study compared to placebo. Interpretation This pilot study indicated that flecainide was safe and potentially biologically effective in ALS. There was evidence that flecainide stabilized peripheral axonal membrane function in ALS. While the study was not powered to detect evidence of benefit of flecainide on ALS-FRS-r decline, further studies may demonstrate clinical efficacy of flecainide in ALS. To determine safety and neuroprotective potential, a double-blind, placebo-controlled, randomised trial of the Na+ channel blocking agent flecainide was conducted in ALS. Flecainide was well tolerated, with no serious adverse events. Although there was some evidence that flecainide stabilised peripheral axonal membrane function, the study was not powered to provide evidence of benefit on functional decline.
Changes in nerve excitability function occur in patients with amyotrophic lateral sclerosis (ALS). We conducted a double-blind, placebo-controlled, randomised clinical trial to examine the impact of a membrane/nerve stabilizer (flecainide) in ALS patients. Although there was some evidence that flecainide stabilised peripheral axonal membrane function in ALS, the study was not powered to find evidence that flecainide benefited patient function.
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Uncini A, Kuwabara S. Nodopathies of the peripheral nerve: an emerging concept. J Neurol Neurosurg Psychiatry 2015; 86:1186-95. [PMID: 25699569 DOI: 10.1136/jnnp-2014-310097] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 01/31/2015] [Indexed: 12/17/2022]
Abstract
Peripheral nerve diseases are traditionally classified as demyelinating or axonal. It has been recently proposed that microstructural changes restricted to the nodal/paranodal region may be the key to understanding the pathophysiology of antiganglioside antibody mediated neuropathies. We reviewed neuropathies with different aetiologies (dysimmune, inflammatory, ischaemic, nutritional, toxic) in which evidence from nerve conductions, excitability studies, pathology and animal models, indicate the involvement of the nodal region in the pathogenesis. For these neuropathies, the classification in demyelinating and axonal is inadequate or even misleading, we therefore propose a new category of nodopathy that has the following features: (1) it is characterised by a pathophysiological continuum from transitory nerve conduction block to axonal degeneration; (2) the conduction block may be due to paranodal myelin detachment, node lengthening, dysfunction or disruption of Na(+) channels, altered homeostasis of water and ions, or abnormal polarisation of the axolemma; (3) the conduction block may be promptly reversible without development of excessive temporal dispersion; (4) axonal degeneration, depending on the specific disorder and its severity, eventually follows the conduction block. The term nodopathy focuses to the site of primary nerve injury, avoids confusion with segmental demyelinating neuropathies and circumvents the apparent paradox that something axonal may be reversible and have a good prognosis.
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Affiliation(s)
- Antonino Uncini
- Department of Neuroscience, Imaging and Clinical Sciences, University "G d'Annunzio", Chieti-Pescara, Chieti, Italy
| | - Satoshi Kuwabara
- Department of Neurology, Graduate School of Medicine, Chiba University, Chiba, Japan
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Moldovan M, Alvarez S, Rosberg MR, Krarup C. Persistent alterations in active and passive electrical membrane properties of regenerated nerve fibers of man and mice. Eur J Neurosci 2015; 43:388-403. [DOI: 10.1111/ejn.13047] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Revised: 07/31/2015] [Accepted: 08/13/2015] [Indexed: 12/12/2022]
Affiliation(s)
- Mihai Moldovan
- Department of Neuroscience and Pharmacology; University of Copenhagen; Copenhagen Denmark
- Department of Clinical Neurophysiology; NF3063 Rigshospitalet 9 Blegdamsvej 2100 Copenhagen Denmark
| | - Susana Alvarez
- Department of Neuroscience and Pharmacology; University of Copenhagen; Copenhagen Denmark
- Department of Clinical Neurophysiology; NF3063 Rigshospitalet 9 Blegdamsvej 2100 Copenhagen Denmark
| | - Mette R. Rosberg
- Department of Neuroscience and Pharmacology; University of Copenhagen; Copenhagen Denmark
- Department of Clinical Neurophysiology; NF3063 Rigshospitalet 9 Blegdamsvej 2100 Copenhagen Denmark
| | - Christian Krarup
- Department of Neuroscience and Pharmacology; University of Copenhagen; Copenhagen Denmark
- Department of Clinical Neurophysiology; NF3063 Rigshospitalet 9 Blegdamsvej 2100 Copenhagen Denmark
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Liu Y, Holdbrooks AT, Meares GP, Buckley JA, Benveniste EN, Qin H. Preferential Recruitment of Neutrophils into the Cerebellum and Brainstem Contributes to the Atypical Experimental Autoimmune Encephalomyelitis Phenotype. THE JOURNAL OF IMMUNOLOGY 2015; 195:841-52. [PMID: 26085687 DOI: 10.4049/jimmunol.1403063] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 05/22/2015] [Indexed: 01/03/2023]
Abstract
The JAK/STAT pathway is critical for development, regulation, and termination of immune responses, and dysregulation of the JAK/STAT pathway, that is, hyperactivation, has pathological implications in autoimmune and neuroinflammatory diseases. Suppressor of cytokine signaling 3 (SOCS3) regulates STAT3 activation in response to cytokines that play important roles in the pathogenesis of neuroinflammatory diseases, including IL-6 and IL-23. We previously demonstrated that myeloid lineage-specific deletion of SOCS3 resulted in a severe, nonresolving atypical form of experimental autoimmune encephalomyelitis (EAE), characterized by lesions, inflammatory infiltrates, elevated STAT activation, and elevated cytokine and chemokine expression in the cerebellum. Clinically, these mice exhibit ataxia and tremors. In this study, we provide a detailed analysis of this model, demonstrating that the atypical EAE observed in LysMCre-SOCS3(fl/fl) mice is characterized by extensive neutrophil infiltration into the cerebellum and brainstem, increased inducible NO synthase levels in the cerebellum and brainstem, and prominent axonal damage. Importantly, infiltrating SOCS3-deficient neutrophils produce high levels of CXCL2, CCL2, CXCL10, NO, TNF-α, and IL-1β. Kinetic studies demonstrate that neutrophil infiltration into the cerebellum and brainstem of LysMCre-SOCS3(fl/fl) mice closely correlates with atypical EAE clinical symptoms. Ab-mediated depletion of neutrophils converts the atypical phenotype to the classical EAE phenotype and, in some cases, a mixed atypical/classical phenotype. Blocking CXCR2 signaling ameliorates atypical EAE development by reducing neutrophil infiltration into the cerebellum/brainstem. Thus, neutrophils lacking SOCS3 display elevated STAT3 activation and expression of proinflammatory mediators and play a critical role in the development of atypical EAE.
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Affiliation(s)
- Yudong Liu
- Department of Cell, Developmental and Integrative Biology, The University of Alabama at Birmingham, Birmingham, AL 35294
| | - Andrew T Holdbrooks
- Department of Cell, Developmental and Integrative Biology, The University of Alabama at Birmingham, Birmingham, AL 35294
| | - Gordon P Meares
- Department of Cell, Developmental and Integrative Biology, The University of Alabama at Birmingham, Birmingham, AL 35294
| | - Jessica A Buckley
- Department of Cell, Developmental and Integrative Biology, The University of Alabama at Birmingham, Birmingham, AL 35294
| | - Etty N Benveniste
- Department of Cell, Developmental and Integrative Biology, The University of Alabama at Birmingham, Birmingham, AL 35294
| | - Hongwei Qin
- Department of Cell, Developmental and Integrative Biology, The University of Alabama at Birmingham, Birmingham, AL 35294
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Abstract
Patients suffering from DN (diabetic neuropathy) suffer from the coexistence of positive (i.e. pain, hypersensitivity, tingling, cramps, cold feet, etc.) and negative (i.e. loss of sensory perception, delayed wound healing, etc.) symptoms. Elevated blood glucose alone cannot explain the development and progression of DN. Recently it has been shown that the endogenous reactive metabolite MG (methylglyoxal), elevated as a consequence of reduced Glo1 (glyoxalase I), can contribute to the gain of function via post-translational modification of neuronal ion channels involved in chemosensing and action potential generation in nociceptive nerve endings. The effects of dicarbonyls on the neuronal compartment provides a unifying mechanism for the development of DN. Targeting the accumulation and effects of MG may therefore provide new, more effective, therapeutic approaches for the treatment of DN.
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Franssen H. Relation between symptoms and pathophysiology in inflammatory neuropathies: Controversies and hypotheses. Neurosci Lett 2015; 596:84-9. [PMID: 25483620 DOI: 10.1016/j.neulet.2014.12.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 11/11/2014] [Accepted: 12/02/2014] [Indexed: 10/24/2022]
Abstract
This review attempts to explain the symptoms experienced by patients with inflammatory neuropathies by pathophysiological events. The emphasis is not on the primary events that may cause a particular illness but on downstream events taking place in peripheral nerves or muscles. Symptoms that will be discussed include sensory predominance, motor predominance, activity-induced weakness, heat paresis, and cold paresis. Each symptom is associated with, but not limited to, particular neuropathies.
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Affiliation(s)
- Hessel Franssen
- Brain Center Rudolf Magnus, Section Neuromuscular Disorders, Department of Neurology F02.230, University Medical Center Utrecht, Heidelberglaan 100, 3584CX Utrecht, Netherlands.
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Mitochondrial immobilization mediated by syntaphilin facilitates survival of demyelinated axons. Proc Natl Acad Sci U S A 2014; 111:9953-8. [PMID: 24958879 DOI: 10.1073/pnas.1401155111] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Axonal degeneration is a primary cause of permanent neurological disability in individuals with the CNS demyelinating disease multiple sclerosis. Dysfunction of axonal mitochondria and imbalanced energy demand and supply are implicated in degeneration of chronically demyelinated axons. The purpose of this study was to define the roles of mitochondrial volume and distribution in axonal degeneration following acute CNS demyelination. We show that the axonal mitochondrial volume increase following acute demyelination of WT CNS axons does not occur in demyelinated axons deficient in syntaphilin, an axonal molecule that immobilizes stationary mitochondria to microtubules. These findings were supported by time-lapse imaging of WT and syntaphilin-deficient axons in vitro. When demyelinated, axons deficient in syntaphilin degenerate at a significantly greater rate than WT axons, and this degeneration can be rescued by reducing axonal electrical activity with the Na(+) channel blocker flecainide. These results support the concept that syntaphilin-mediated immobilization of mitochondria to microtubules is required for the volume increase of axonal mitochondria following acute demyelination and protects against axonal degeneration in the CNS.
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Liu S, Zwinger P, Black J, Waxman S. Tapered withdrawal of phenytoin removes protective effect in EAE without inflammatory rebound and mortality. J Neurol Sci 2014; 341:8-12. [DOI: 10.1016/j.jns.2014.03.029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 03/13/2014] [Indexed: 11/29/2022]
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Ljubisavljevic S, Stojanovic I, Pavlovic R, Pavlovic D. The importance of nitric oxide and arginase in the pathogenesis of acute neuroinflammation: are those contra players with the same direction? Neurotox Res 2014; 26:392-9. [PMID: 24770974 DOI: 10.1007/s12640-014-9470-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Revised: 04/08/2014] [Accepted: 04/10/2014] [Indexed: 11/28/2022]
Abstract
To investigate the concentrations of nitric oxide (NO) products (NOx) and arginase activity in acute neuroinflammation, we analyzed cerebrospinal fluid (CSF) and plasma of clinically isolated syndrome (CIS) and relapsing remitting multiple sclerosis (RRMS) patients, who were divided into groups on the basis of clinical and radiological disease activity. The NOx levels, in both, CSF and plasma, were increased in CIS (p = 0.0015, p = 0.0014, respectively) and RRMS group (p = 0.002, p = 0.0019, respectively), while arginase activity approached low levels, in CIS (p = 0.009, p = 0.02, respectively) and RRMS group (p = 0.018, p = 0.034, respectively) compared to controls. The NOx levels were higher in CSF and plasma of CIS than in RRMS group (p = 0.065, p = 0.037, respectively), inverse to arginase activity which was higher, in CSF and plasma, in RRMS than in CIS group (p = 0.031, p = 0.02, respectively). The CSF and plasma NOx values positively correlated with the clinical disease activity in CIS (r = 0.09, p = 0.81; r = 0.45, p = 0.023, respectively) and RRMS group (r = 0.311, p = 0.04; r = 0.512, p = 0.01, respectively). Also, CSF and plasma arginase activity showed negative correlation with clinical disease activity in CIS (r = 0.39, p = 0.03; r = 0.1, p = 0.65, respectively) and RRMS group (r = 0.43, p = 0.03; r = 0.62, p = 0.015, respectively). The CSF NOx levels showed positive correlation with volume of acute radiological lesions of CNS in CIS (r = 0.25, p = 0.045) and RRMS group (r = 0.31, p = 0.04), while arginase activity showed the negative correlations in CIS (r = 0.41; p = 0.035) and RRMS group (r = 0.52, p = 0.022). The results support NO and arginase involvement in the pathogenesis of acute neuroinflammation, which determination may be useful as surrogate markers for clinical and radiological disease activity.
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Affiliation(s)
- Srdjan Ljubisavljevic
- Clinic of Neurology, Clinical Center Nis, Bul. Dr Zorana Djindjica 48, 18000, Nis, Serbia,
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Abstract
The last 20 years have seen major progress in the treatment of relapsing-remitting multiple sclerosis (RRMS) using a variety of drugs targeting immune dysfunction. In contrast, all clinical trials of such agents in primary progressive multiple sclerosis (PPMS) have failed and there is limited evidence of their efficacy in secondary progressive disease. Evolving concepts of the complex interplay between inflammatory and neurodegenerative processes across the course of multiple sclerosis (MS) may explain this discrepancy. This paper will provide an up-to-date overview of the rationale and results of the published clinical trials that have sought to alter the trajectory of both primary and secondary MS, considering studies involving drugs with a primary immune target and also those aiming for neuroprotection. Future areas of study will be discussed, building on these results combined with the experience of treating RRMS and new concepts emerging from laboratory science and animal models.
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Affiliation(s)
- Giancarlo Comi
- Department of Neurology, Università Vita-Salute San Raffaele, Italy
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46
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Abstract
Guillain-Barre syndrome is a postinfectious disorder caused by an aberrant immune response to an infectious pathogen, resulting in an autoimmune disease. As with other autoimmune diseases of infectious nature, the intricate balance of the numerous factors involved in the immune response may determine the outcome of the interaction between the microbe and host. Recent studies focusing on the role of cytokines and its network of related mediators and receptors suggest that any imbalance may make a significant contribution to the outcome of the infectious disease process. Better understanding of the pathogenesis of Guillain-Barre syndrome may lead to the discovery of newer therapeutics and may also serve as a model for studying other autoimmune diseases.
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Affiliation(s)
- Raymond Sw Tsang
- CNS Infection and Vaccine Preventable Bacterial Diseases, National Microbiology Laboratory, Health Canada, 1015 Arlington Street, Winnipeg, Manitoba, R3E 3R2, USA.
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Lim ET, Giovannoni G. Immunopathogenesis and immunotherapeutic approaches in multiple sclerosis. Expert Rev Neurother 2014; 5:379-90. [PMID: 15938671 DOI: 10.1586/14737175.5.3.379] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Multiple sclerosis is an organ-specific autoimmune disease, characterized pathologically by cell-mediated inflammation, demyelination and variable degrees of axonal loss. Although inflammation is considered central to the pathogenesis of multiple sclerosis, to date, the only licensed and hence widely used multiple sclerosis immunotherapies are interferon-beta, glatiramer acetate and mitoxantrone. This review discusses the immunopathogenesis of multiple sclerosis, focusing on a number of emerging immunotherapies. A number of new approaches likely to manipulate the immunopathogenesis of multiple sclerosis and which may ultimately allow for the development of more effective immunotherapy are also highlighted.
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Affiliation(s)
- Ee Tuan Lim
- University College London, Department of Neuroinflammation, Institute of Neurology, Queen Square, London, WC1N 3BG, UK
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Criste G, Trapp B, Dutta R. Axonal loss in multiple sclerosis: causes and mechanisms. HANDBOOK OF CLINICAL NEUROLOGY 2014; 122:101-13. [PMID: 24507515 DOI: 10.1016/b978-0-444-52001-2.00005-4] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system and the leading cause of non-traumatic neurologic disability in young adults in the United States and Europe. The disease course is variable and starts with reversible episodes of neurologic disability which transforms into continuous and irreversible neurologic decline. It is well established that loss of axons and neurons is the major cause of the progressive neurologic decline that most MS patients endure. Current hypotheses support primary inflammatory demyelination as the underlying cause of axonal loss during earlier stages in MS. The transition to progressive disease course is thought to occur when a threshold of neuronal and axonal loss is reached and the compensatory capacity of the central nervous system is surpassed. Available immunomodulatory therapies are of little benefit to MS after entering this irreversible phase of the disease. Elucidation of mechanisms that are responsible for axonal loss is therefore essential for the development of therapies directed to stop neurologic decline in MS patients. The current chapter reviews existing data on mechanisms of axonal pathology in MS.
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Affiliation(s)
- Gerson Criste
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Bruce Trapp
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA.
| | - Ranjan Dutta
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
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Curcumin protects axons from degeneration in the setting of local neuroinflammation. Exp Neurol 2013; 253:102-10. [PMID: 24382451 DOI: 10.1016/j.expneurol.2013.12.016] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 11/29/2013] [Accepted: 12/19/2013] [Indexed: 11/24/2022]
Abstract
Axon degeneration is a hallmark of several central nervous system (CNS) disorders, including multiple sclerosis (MS), Alzheimer's disease (AD) and Parkinson's disease (PD). Previous neuroprotective approaches have mainly focused on reversal or prevention of neuronal cell body degeneration or death. However, experimental evidence suggests that mechanisms of axon degeneration may differ from cell death mechanisms, and that therapeutic agents that protect cell bodies may not protect axons. Moreover, axon degeneration underlies neurologic disability and may, in some cases, represent an important initial step that leads to neuronal death. Here, we develop a novel quantitative microfluidic-based methodology to assess mechanisms of axon degeneration caused by local neuroinflammation. We find that LPS-stimulated microglia release soluble factors that, when applied locally to axons, result in axon degeneration. This local axon degeneration is mediated by microglial MyD88/p38 MAPK signaling and concomitant production of nitric oxide (NO). Intra-axonal mechanisms of degeneration involve JNK phosphorylation. Curcumin, a compound with both anti-oxidant and JNK inhibitory properties, specifically protects axons, but not neuronal cell bodies, from NO-mediated degeneration. Overall, our platform provides mechanistic insights into local axon degeneration, identifies curcumin as a novel axon protectant in the setting of neuroinflammation, and allows for ready screening of axon protective drugs.
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Miljković D, Spasojević I. Multiple sclerosis: molecular mechanisms and therapeutic opportunities. Antioxid Redox Signal 2013; 19:2286-334. [PMID: 23473637 PMCID: PMC3869544 DOI: 10.1089/ars.2012.5068] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2012] [Revised: 02/09/2012] [Accepted: 03/09/2013] [Indexed: 12/15/2022]
Abstract
The pathophysiology of multiple sclerosis (MS) involves several components: redox, inflammatory/autoimmune, vascular, and neurodegenerative. All of them are supported by the intertwined lines of evidence, and none of them should be written off. However, the exact mechanisms of MS initiation, its development, and progression are still elusive, despite the impressive pace by which the data on MS are accumulating. In this review, we will try to integrate the current facts and concepts, focusing on the role of redox changes and various reactive species in MS. Knowing the schedule of initial changes in pathogenic factors and the key turning points, as well as understanding the redox processes involved in MS pathogenesis is the way to enable MS prevention, early treatment, and the development of therapies that target specific pathophysiological components of the heterogeneous mechanisms of MS, which could alleviate the symptoms and hopefully stop MS. Pertinent to this, we will outline (i) redox processes involved in MS initiation; (ii) the role of reactive species in inflammation; (iii) prooxidative changes responsible for neurodegeneration; and (iv) the potential of antioxidative therapy.
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Affiliation(s)
- Djordje Miljković
- Department of Immunology, Institute for Biological Research “Siniša Stanković,” University of Belgrade, Belgrade, Serbia
| | - Ivan Spasojević
- Life Sciences Department, Institute for Multidisciplinary Research, University of Belgrade, Belgrade, Serbia
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