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Experimental model of small subcortical infarcts in mice with long-lasting functional disabilities. Brain Res 2015; 1629:318-28. [DOI: 10.1016/j.brainres.2015.10.039] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 10/11/2015] [Accepted: 10/22/2015] [Indexed: 01/04/2023]
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Theoret JK, Jadavji NM, Zhang M, Smith PD. Granulocyte macrophage colony-stimulating factor treatment results in recovery of motor function after white matter damage in mice. Eur J Neurosci 2015; 43:17-24. [PMID: 26474338 DOI: 10.1111/ejn.13105] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 09/29/2015] [Accepted: 10/13/2015] [Indexed: 11/30/2022]
Abstract
Clinical stroke usually results from a cerebral ischaemic event, and is frequently a debilitating condition with limited treatment options. A significant proportion of clinical strokes result from specific damage to the subcortical white matter (SWM), but currently there are few animal models available to investigate the pathogenesis and potential therapeutic strategies to promote recovery. Granulocyte macrophage colony-stimulating factor (GM-CSF) is a cytokine that has been previously shown to promote neuroprotective effects after brain damage; however, the mechanisms mediating this effect are not known. Here, it is reported that GM-CSF treatment results in dramatic functional improvement in a white matter model of stroke in mice. SWM stroke was induced in mice by unilateral injections of the vasoconstrictor, endothelin-1 (ET-1). The results reveal that ET-1-induced stroke impairs skilled motor function on the single pellet-reaching task and results in forelimb asymmetry, in adult mice. Treatment with GM-CSF, after stroke, restores motor function and abolishes forelimb asymmetry. The results also indicate that GM-CSF promotes its effects by activating mammalian target of rapamycin signalling mechanisms in the brain following stroke injury. Additionally, a significant increase in GM-CSF receptor expression was found in the ipsilateral hemisphere of the ET-1-injected brain. Taken together, the present study highlights the use of an under-utilized mouse model of stroke (using ET-1) and suggests that GM-CSF treatment can attenuate ET-1-induced functional deficits.
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Affiliation(s)
- Jennifer K Theoret
- Neuroscience Department, Carleton University, 1125 Colonel By Drive, Ottawa, ON, Canada
| | - Nafisa M Jadavji
- Neuroscience Department, Carleton University, 1125 Colonel By Drive, Ottawa, ON, Canada
| | - Min Zhang
- Neuroscience Department, Carleton University, 1125 Colonel By Drive, Ottawa, ON, Canada
| | - Patrice D Smith
- Neuroscience Department, Carleton University, 1125 Colonel By Drive, Ottawa, ON, Canada
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Byblow WD, Stinear CM, Barber PA, Petoe MA, Ackerley SJ. Proportional recovery after stroke depends on corticomotor integrity. Ann Neurol 2015; 78:848-59. [PMID: 26150318 DOI: 10.1002/ana.24472] [Citation(s) in RCA: 260] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 06/28/2015] [Accepted: 06/29/2015] [Indexed: 01/08/2023]
Abstract
OBJECTIVE For most patients, resolution of upper limb impairment during the first 6 months poststroke is 70% of the maximum possible. We sought to identify candidate mechanisms of this proportional recovery. We hypothesized that proportional resolution of upper limb impairment depends on ipsilesional corticomotor pathway function, is mirrored by proportional recovery of excitability in this pathway, and is unaffected by upper limb therapy dose. METHODS Upper limb impairment was measured in 93 patients at 2, 6, 12, and 26 weeks after first-ever ischemic stroke. Motor evoked potentials (MEPs) and motor threshold were recorded from extensor carpi radialis using transcranial magnetic stimulation, and fractional anisotropy (FA) in the posterior limbs of the internal capsules was determined with diffusion-weighted magnetic resonance imaging. RESULTS Initial impairment score, presence of MEPs and FA asymmetry were the only predictors of impairment resolution, indicating a key role for corticomotor tract function. By 12 weeks, upper limb impairment resolved by 70% in patients with MEPs regardless of their initial impairment, and ipsilesional rest motor threshold also resolved by 70%. Resolution of impairment was insensitive to upper limb therapy dose. INTERPRETATION These findings indicate that upper limb impairment resolves by 70% of the maximum possible, regardless of initial impairment, but only for patients with intact corticomotor function. Impairment resolution seems to reflect spontaneous neurobiological processes that involve the ipsilesional corticomotor pathway. A better understanding of these mechanisms could lead to interventions that increase resolution of impairment above 70%.
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Affiliation(s)
- Winston D Byblow
- Center for Brain Research, University of Auckland, Auckland, New Zealand.,Department of Sport & Exercise Science, University of Auckland, Auckland, New Zealand
| | - Cathy M Stinear
- Center for Brain Research, University of Auckland, Auckland, New Zealand.,Department of Medicine, University of Auckland, Auckland, New Zealand
| | - P Alan Barber
- Center for Brain Research, University of Auckland, Auckland, New Zealand.,Department of Medicine, University of Auckland, Auckland, New Zealand
| | - Matthew A Petoe
- Center for Brain Research, University of Auckland, Auckland, New Zealand.,Department of Medicine, University of Auckland, Auckland, New Zealand.,Bionics Institute of Australia, Melbourne, Australia
| | - Suzanne J Ackerley
- Center for Brain Research, University of Auckland, Auckland, New Zealand.,Department of Medicine, University of Auckland, Auckland, New Zealand
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Ahmad AS, Satriotomo I, Fazal JA, Nadeau SE, Doré S. Optimization of a Clinically Relevant Model of White Matter Stroke in Mice: Histological and Functional Evidences. ACTA ACUST UNITED AC 2015; 2. [PMID: 27512724 DOI: 10.19104/jnn.2015.14] [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] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND PURPOSE White matter (WM) injury during stroke increases the risk of disability and gloomy prognosis of post-stroke rehabilitation. However, modeling of WM loss in rodents has proven to be challenging. METHODS We report improved WM injury models in male C57BL/6 mice. Mice were given either endothelin-1 (ET-1) or L-N5-(1-iminoethyl)ornitine (L-NIO) into the periventricular white matter (PVWM), in the corpus callosum (CC), or in the posterior limb of internal capsule (PLIC). Anatomical and functional outcomes were quantified on day 7 post injection. RESULTS Injection of ET-1 or L-NIO caused a small focal lesion in the injection site in the PVWM. No significant motor function deficits were observed in the PVWM lesion model. We next targeted the PLIC by using single or double injections of L-NIO and found that this strategy induced small focal infarction. Interestingly, injection of L-NIO in the PLIC also resulted in gliosis, and significant motor function deficits. CONCLUSIONS By employing different agents, doses, and locations, this study shows the feasibility of inducing brain WM injury accompanied with functional deficits in mice. Selective targeting of the injury location, behavioral testing, and the agents chosen to induce WM injury are all keys to successfully develop a mouse model and subsequent testing of therapeutic interventions against WM injury.
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Affiliation(s)
- Abdullah S Ahmad
- Department of Anesthesiology and Center for Translational Research in Neurodegenerative Disease, University of Florida, FL, USA
| | - Irawan Satriotomo
- Department of Anesthesiology and Center for Translational Research in Neurodegenerative Disease, University of Florida, FL, USA
| | - Jawad A Fazal
- Department of Anesthesiology and Center for Translational Research in Neurodegenerative Disease, University of Florida, FL, USA
| | - Stephen E Nadeau
- Research Service and the Brain Rehabilitation Research Center, Malcom Randall Veterans Affairs Medical Center, FL, USA; Department of Neurology, University of Florida College of Medicine, Gainesville, FL, USA
| | - Sylvain Doré
- Department of Anesthesiology and Center for Translational Research in Neurodegenerative Disease, University of Florida, FL, USA; Departments of Neuroscience, Neurology, and Psychiatry, University of Florida, Gainesville, FL, USA
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Ahmad AS, Satriotomo I, Fazal J, Nadeau SE, Doré S. Considerations for the Optimization of Induced White Matter Injury Preclinical Models. Front Neurol 2015; 6:172. [PMID: 26322013 PMCID: PMC4532913 DOI: 10.3389/fneur.2015.00172] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 07/20/2015] [Indexed: 11/13/2022] Open
Abstract
White matter (WM) injury in relation to acute neurologic conditions, especially stroke, has remained obscure until recently. Current advances in imaging technologies in the field of stroke have confirmed that WM injury plays an important role in the prognosis of stroke and suggest that WM protection is essential for functional recovery and post-stroke rehabilitation. However, due to the lack of a reproducible animal model of WM injury, the pathophysiology and mechanisms of this injury are not well studied. Moreover, producing selective WM injury in animals, especially in rodents, has proven to be challenging. Problems associated with inducing selective WM ischemic injury in the rodent derive from differences in the architecture of the brain, most particularly, the ratio of WM to gray matter in rodents compared to humans, the agents used to induce the injury, and the location of the injury. Aging, gender differences, and comorbidities further add to this complexity. This review provides a brief account of the techniques commonly used to induce general WM injury in animal models (stroke and non-stroke related) and highlights relevance, optimization issues, and translational potentials associated with this particular form of injury.
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Affiliation(s)
- Abdullah Shafique Ahmad
- Department of Anesthesiology, Center for Translational Research in Neurodegenerative Disease, University of Florida , Gainesville, FL , USA
| | - Irawan Satriotomo
- Department of Anesthesiology, Center for Translational Research in Neurodegenerative Disease, University of Florida , Gainesville, FL , USA
| | - Jawad Fazal
- Department of Anesthesiology, Center for Translational Research in Neurodegenerative Disease, University of Florida , Gainesville, FL , USA
| | - Stephen E Nadeau
- Research Service, Brain Rehabilitation Research Center, Malcom Randall Veterans Affairs Medical Center , Gainesville, FL , USA ; Department of Neurology, University of Florida , Gainesville, FL , USA
| | - Sylvain Doré
- Department of Anesthesiology, Center for Translational Research in Neurodegenerative Disease, University of Florida , Gainesville, FL , USA ; Research Service, Brain Rehabilitation Research Center, Malcom Randall Veterans Affairs Medical Center , Gainesville, FL , USA ; Department of Neurology, University of Florida , Gainesville, FL , USA ; Department of Neuroscience, University of Florida , Gainesville, FL , USA ; Department of Neurology, University of Florida , Gainesville, FL , USA ; Department of Pharmaceutics, University of Florida , Gainesville, FL , USA ; Department of Psychology, University of Florida , Gainesville, FL , USA ; Department of Psychiatry, University of Florida , Gainesville, FL , USA
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Blasi F, Whalen MJ, Ayata C. Lasting pure-motor deficits after focal posterior internal capsule white-matter infarcts in rats. J Cereb Blood Flow Metab 2015; 35:977-84. [PMID: 25649992 PMCID: PMC4640262 DOI: 10.1038/jcbfm.2015.7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 12/26/2014] [Accepted: 12/30/2014] [Indexed: 11/10/2022]
Abstract
Small white-matter infarcts of the internal capsule are clinically prevalent but underrepresented among currently available animal models of ischemic stroke. In particular, the assessment of long-term outcome, a primary end point in clinical practice, has been challenging due to mild deficits and the rapid and often complete recovery in most experimental models. We, therefore, sought to develop a focal white-matter infarction model that can mimic the lasting neurologic deficits commonly observed in stroke patients. The potent vasoconstrictor endothelin-1 (n=24) or vehicle (n=9) was stereotactically injected into the internal capsule at one of three antero-posterior levels (1, 2, or 3 mm posterior to bregma) in male Sprague-Dawley rats. Endothelin-injected animals showed highly focal (~1 mm(3)) and reproducible ischemic infarcts, with severe axonal and myelin loss accompanied by cellular infiltration when examined 2 and 4 weeks after injection. Only those rats injected with endothelin-1 at the most posterior location developed robust and pure-motor deficits in adhesive removal, cylinder and foot-fault tests that persisted at 1 month, without detectable sensory impairments. In summary, we present an internal capsule stroke model optimized to produce lasting pure-motor deficits in rats that may be suitable to study neurologic recovery and rehabilitation after white-matter injury.
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Affiliation(s)
- Francesco Blasi
- Neurovascular Research Laboratory, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Michael J Whalen
- 1] Neuroscience Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA [2] Department of Pediatrics, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
| | - Cenk Ayata
- 1] Neurovascular Research Laboratory, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA [2] Stroke Service and Neuroscience Intensive Care Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
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Internal capsule stroke in the common marmoset. Neuroscience 2015; 284:400-411. [DOI: 10.1016/j.neuroscience.2014.10.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Revised: 09/28/2014] [Accepted: 10/01/2014] [Indexed: 12/27/2022]
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Ramos-Cejudo J, Gutiérrez-Fernández M, Otero-Ortega L, Rodríguez-Frutos B, Fuentes B, Vallejo-Cremades MT, Hernanz TN, Cerdán S, Díez-Tejedor E. Brain-derived neurotrophic factor administration mediated oligodendrocyte differentiation and myelin formation in subcortical ischemic stroke. Stroke 2014; 46:221-8. [PMID: 25395417 DOI: 10.1161/strokeaha.114.006692] [Citation(s) in RCA: 114] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND AND PURPOSE Translational research is beginning to reveal the importance of trophic factors as a therapy for cellular brain repair. The purpose of this study was to analyze whether brain-derived neurotrophic factor (BDNF) administration could mediate oligodendrogenesis and remyelination after white matter injury in subcortical stroke. METHODS Ischemia was induced in rats by injection of endothelin-1. At 24 hours, 0.4 μg/kg of BDNF or saline was intravenously administered to the treatment and control groups, respectively. Functional evaluation, MRI, and fiber tract integrity on tractography images were analyzed. Proliferation (KI-67) and white matter repair markers (A2B5, 2',3'-cyclic-nucleotide 3'-phosphodiesterase [CNPase], adenomatous polyposis coli [APC], platelet-derived growth factor receptor alpha [PDGFR-α], oligodendrocyte marker O4 [O4], oligodendrocyte transcription factor [Olig-2], and myelin basic protein [MBP]) were analyzed at 7 and 28 days. RESULTS The BDNF-treated animals showed less functional deficit at 28 days after treatment than the controls (P<0.05). Although T2-MRI did not show differences in lesion size at 7 and 28 days between groups, diffusion tensor imaging tractography analysis revealed significantly better tract connectivity at 28 days in the BDNF group than in the controls (P<0.05). Increased proliferation of oligodendrocyte progenitors was observed in treated animals at 7 days (P<0.05). Finally, the levels of white matter repair markers (A2B5, CNPase, and O4 at 7 days; Olig-2 and MBP at 28 days) were higher in the BDNF group than in the controls (P<0.05). CONCLUSIONS BDNF administration exerted better functional outcome, oligodendrogenesis, remyelination, and fiber connectivity than controls in rats subjected to subcortical damage in ischemic stroke.
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Affiliation(s)
- Jaime Ramos-Cejudo
- From the Department of Neurology and Stroke Center, Neuroscience and Cerebrovascular Research Laboratory, La Paz University Hospital, Neuroscience Area of IdiPAZ Health Research Institute, Autónoma University of Madrid, Madrid, Spain (J.R.-C., M.G.-F., L.O.-O., B.R.-F., B.F., M.T.V.-C., E.D.-T.); and Laboratory for Imaging and Spectroscopy by Magnetic Resonance (LISMAR), Institute of Biomedical Research Alberto Sols, CSIC-UAM, Madrid, Spain (T.N.H., S.C.)
| | - María Gutiérrez-Fernández
- From the Department of Neurology and Stroke Center, Neuroscience and Cerebrovascular Research Laboratory, La Paz University Hospital, Neuroscience Area of IdiPAZ Health Research Institute, Autónoma University of Madrid, Madrid, Spain (J.R.-C., M.G.-F., L.O.-O., B.R.-F., B.F., M.T.V.-C., E.D.-T.); and Laboratory for Imaging and Spectroscopy by Magnetic Resonance (LISMAR), Institute of Biomedical Research Alberto Sols, CSIC-UAM, Madrid, Spain (T.N.H., S.C.).
| | - Laura Otero-Ortega
- From the Department of Neurology and Stroke Center, Neuroscience and Cerebrovascular Research Laboratory, La Paz University Hospital, Neuroscience Area of IdiPAZ Health Research Institute, Autónoma University of Madrid, Madrid, Spain (J.R.-C., M.G.-F., L.O.-O., B.R.-F., B.F., M.T.V.-C., E.D.-T.); and Laboratory for Imaging and Spectroscopy by Magnetic Resonance (LISMAR), Institute of Biomedical Research Alberto Sols, CSIC-UAM, Madrid, Spain (T.N.H., S.C.)
| | - Berta Rodríguez-Frutos
- From the Department of Neurology and Stroke Center, Neuroscience and Cerebrovascular Research Laboratory, La Paz University Hospital, Neuroscience Area of IdiPAZ Health Research Institute, Autónoma University of Madrid, Madrid, Spain (J.R.-C., M.G.-F., L.O.-O., B.R.-F., B.F., M.T.V.-C., E.D.-T.); and Laboratory for Imaging and Spectroscopy by Magnetic Resonance (LISMAR), Institute of Biomedical Research Alberto Sols, CSIC-UAM, Madrid, Spain (T.N.H., S.C.)
| | - Blanca Fuentes
- From the Department of Neurology and Stroke Center, Neuroscience and Cerebrovascular Research Laboratory, La Paz University Hospital, Neuroscience Area of IdiPAZ Health Research Institute, Autónoma University of Madrid, Madrid, Spain (J.R.-C., M.G.-F., L.O.-O., B.R.-F., B.F., M.T.V.-C., E.D.-T.); and Laboratory for Imaging and Spectroscopy by Magnetic Resonance (LISMAR), Institute of Biomedical Research Alberto Sols, CSIC-UAM, Madrid, Spain (T.N.H., S.C.)
| | - Maria Teresa Vallejo-Cremades
- From the Department of Neurology and Stroke Center, Neuroscience and Cerebrovascular Research Laboratory, La Paz University Hospital, Neuroscience Area of IdiPAZ Health Research Institute, Autónoma University of Madrid, Madrid, Spain (J.R.-C., M.G.-F., L.O.-O., B.R.-F., B.F., M.T.V.-C., E.D.-T.); and Laboratory for Imaging and Spectroscopy by Magnetic Resonance (LISMAR), Institute of Biomedical Research Alberto Sols, CSIC-UAM, Madrid, Spain (T.N.H., S.C.)
| | - Teresa Navarro Hernanz
- From the Department of Neurology and Stroke Center, Neuroscience and Cerebrovascular Research Laboratory, La Paz University Hospital, Neuroscience Area of IdiPAZ Health Research Institute, Autónoma University of Madrid, Madrid, Spain (J.R.-C., M.G.-F., L.O.-O., B.R.-F., B.F., M.T.V.-C., E.D.-T.); and Laboratory for Imaging and Spectroscopy by Magnetic Resonance (LISMAR), Institute of Biomedical Research Alberto Sols, CSIC-UAM, Madrid, Spain (T.N.H., S.C.)
| | - Sebastián Cerdán
- From the Department of Neurology and Stroke Center, Neuroscience and Cerebrovascular Research Laboratory, La Paz University Hospital, Neuroscience Area of IdiPAZ Health Research Institute, Autónoma University of Madrid, Madrid, Spain (J.R.-C., M.G.-F., L.O.-O., B.R.-F., B.F., M.T.V.-C., E.D.-T.); and Laboratory for Imaging and Spectroscopy by Magnetic Resonance (LISMAR), Institute of Biomedical Research Alberto Sols, CSIC-UAM, Madrid, Spain (T.N.H., S.C.)
| | - Exuperio Díez-Tejedor
- From the Department of Neurology and Stroke Center, Neuroscience and Cerebrovascular Research Laboratory, La Paz University Hospital, Neuroscience Area of IdiPAZ Health Research Institute, Autónoma University of Madrid, Madrid, Spain (J.R.-C., M.G.-F., L.O.-O., B.R.-F., B.F., M.T.V.-C., E.D.-T.); and Laboratory for Imaging and Spectroscopy by Magnetic Resonance (LISMAR), Institute of Biomedical Research Alberto Sols, CSIC-UAM, Madrid, Spain (T.N.H., S.C.).
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The node of Ranvier in CNS pathology. Acta Neuropathol 2014; 128:161-75. [PMID: 24913350 PMCID: PMC4102831 DOI: 10.1007/s00401-014-1305-z] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 05/27/2014] [Accepted: 05/27/2014] [Indexed: 12/11/2022]
Abstract
Healthy nodes of Ranvier are crucial for action potential propagation along myelinated axons, both in the central and in the peripheral nervous system. Surprisingly, the node of Ranvier has often been neglected when describing CNS disorders, with most pathologies classified simply as being due to neuronal defects in the grey matter or due to oligodendrocyte damage in the white matter. However, recent studies have highlighted changes that occur in pathological conditions at the node of Ranvier, and at the associated paranodal and juxtaparanodal regions where neurons and myelinating glial cells interact. Lengthening of the node of Ranvier, failure of the electrically resistive seal between the myelin and the axon at the paranode, and retraction of myelin to expose voltage-gated K+ channels in the juxtaparanode, may contribute to altering the function of myelinated axons in a wide range of diseases, including stroke, spinal cord injury and multiple sclerosis. Here, we review the principles by which the node of Ranvier operates and its molecular structure, and thus explain how defects at the node and paranode contribute to neurological disorders.
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Kolb B, Muhammad A. Harnessing the power of neuroplasticity for intervention. Front Hum Neurosci 2014; 8:377. [PMID: 25018713 PMCID: PMC4072970 DOI: 10.3389/fnhum.2014.00377] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Accepted: 05/14/2014] [Indexed: 01/06/2023] Open
Abstract
A fundamental property of the brain is its capacity to change with a wide variety of experiences, including injury. Although there are spontaneous reparative changes following injury, these changes are rarely sufficient to support significant functional recovery. Research on the basic principles of brain plasticity is leading to new approaches to treating the injured brain. We review factors that affect synaptic organization in the normal brain, evidence of spontaneous neuroplasticity after injury, and the evidence that factors including postinjury experience, pharmacotherapy, and cell-based therapies, can form the basis of rehabilitation strategies after brain injuries early in life and in adulthood.
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Affiliation(s)
- Bryan Kolb
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge Lethbridge, AB, Canada
| | - Arif Muhammad
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge Lethbridge, AB, Canada
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El Waly B, Macchi M, Cayre M, Durbec P. Oligodendrogenesis in the normal and pathological central nervous system. Front Neurosci 2014; 8:145. [PMID: 24971048 PMCID: PMC4054666 DOI: 10.3389/fnins.2014.00145] [Citation(s) in RCA: 113] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 05/23/2014] [Indexed: 12/26/2022] Open
Abstract
Oligodendrocytes (OLGs) are generated late in development and myelination is thus a tardive event in the brain developmental process. It is however maintained whole life long at lower rate, and myelin sheath is crucial for proper signal transmission and neuronal survival. Unfortunately, OLGs present a high susceptibility to oxidative stress, thus demyelination often takes place secondary to diverse brain lesions or pathologies. OLGs can also be the target of immune attacks, leading to primary demyelination lesions. Following oligodendrocytic death, spontaneous remyelination may occur to a certain extent. In this review, we will mainly focus on the adult brain and on the two main sources of progenitor cells that contribute to oligodendrogenesis: parenchymal oligodendrocyte precursor cells (OPCs) and subventricular zone (SVZ)-derived progenitors. We will shortly come back on the main steps of oligodendrogenesis in the postnatal and adult brain, and summarize the key factors involved in the determination of oligodendrocytic fate. We will then shed light on the main causes of demyelination in the adult brain and present the animal models that have been developed to get insight on the demyelination/remyelination process. Finally, we will synthetize the results of studies searching for factors able to modulate spontaneous myelin repair.
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Affiliation(s)
- Bilal El Waly
- CNRS, Institut de Biologie du Développement de Marseille UMR 7288, Aix Marseille Université Marseille, France
| | - Magali Macchi
- CNRS, Institut de Biologie du Développement de Marseille UMR 7288, Aix Marseille Université Marseille, France
| | - Myriam Cayre
- CNRS, Institut de Biologie du Développement de Marseille UMR 7288, Aix Marseille Université Marseille, France
| | - Pascale Durbec
- CNRS, Institut de Biologie du Développement de Marseille UMR 7288, Aix Marseille Université Marseille, France
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Abstract
Stroke is one of the leading causes of death worldwide and the biggest reason for long-term disability. Basic research has formed the modern understanding of stroke pathophysiology, and has revealed important molecular, cellular and systemic mechanisms. However, despite decades of research, most translational stroke trials that aim to introduce basic research findings into clinical treatment strategies - most notably in the field of neuroprotection - have failed. Among other obstacles, poor methodological and statistical standards, negative publication bias, and incomplete preclinical testing have been proposed as 'translational roadblocks'. In this article, we introduce the models commonly used in preclinical stroke research, discuss some of the causes of failed translational success and review potential remedies. We further introduce the concept of modeling 'care' of stroke patients, because current preclinical research models the disorder but does not model care or state-of-the-art clinical testing. Stringent statistical methods and controlled preclinical trials have been suggested to counteract weaknesses in preclinical research. We conclude that preclinical stroke research requires (1) appropriate modeling of the disorder, (2) appropriate modeling of the care of stroke patients and (3) an approach to preclinical testing that is similar to clinical testing, including Phase 3 randomized controlled preclinical trials as necessary additional steps before new therapies enter clinical testing.
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Affiliation(s)
- Philipp Mergenthaler
- Department of Experimental Neurology, Charité Universitätsmedizin Berlin, Charitéplatz 1, 10098 Berlin, Germany.
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Hedna VS, Jain S, Rabbani O, Nadeau SE. Mechanisms of arm paresis in middle cerebral artery distribution stroke: Pilot study. ACTA ACUST UNITED AC 2013; 50:1113-22. [DOI: 10.1682/jrrd.2012.10.0194] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 02/27/2013] [Indexed: 11/05/2022]
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Matute C, Domercq M, Pérez-Samartín A, Ransom BR. Protecting white matter from stroke injury. Stroke 2012; 44:1204-11. [PMID: 23212168 DOI: 10.1161/strokeaha.112.658328] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Carlos Matute
- Departamento de Neurociencias, Achucarro Basque Center for Neuroscience, and CIBERNED, Universidad del País Vasco, UPV/EHU, E-48940 Leioa, Vizcaya, Spain.
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