51
|
Yeo SH, Lim ZJI, Mao J, Yau WP. Effects of Central Nervous System Drugs on Recovery After Stroke: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Clin Drug Investig 2018; 37:901-928. [PMID: 28756557 DOI: 10.1007/s40261-017-0558-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND AND OBJECTIVE Pilot trials have suggested that pharmacotherapy may aid stroke recovery. The aim of this study was to systematically review the effects of antidepressants, anti-Alzheimer drugs, anti-Parkinson drugs, central nervous system (CNS) stimulants and piracetam on gross motor function, cognition, disability, dependency and quality of life (QOL) after stroke. METHODS PubMed, EMBASE and the Cochrane Central Register of Controlled Trials databases were searched, and 44 randomized controlled trials that compared outcomes of interest between drug treatment and placebo or no treatment were included. For each study, standardized mean difference (SMD) or mean difference (MD) with 95% confidence interval (CI) were calculated. Meta-analyses were conducted to pool results using either the fixed-effects or random-effects model. RESULTS Selective serotonin reuptake inhibitors (SSRIs) improved gross motor function (SMD 0.54, 95% CI 0.22-0.85; three studies), disability (SMD 0.49, 95% CI 0.32-0.66; 14 studies) and QOL (MD 6.46, 95% CI 4.71-8.22; two studies), but there was insufficient evidence for their use in enhancing global cognition (SMD 0.23, 95% CI -0.01 to 0.46; five studies) and dependency (risk ratio 0.81, 95% CI 0.68-0.97; one fluoxetine study). In particular, gross motor function was improved by fluoxetine (SMD 0.64, 95% CI 0.31-0.98; two studies), while disability was improved by paroxetine (SMD 1.05, 95% CI 0.63-1.46; two studies), citalopram (SMD 0.51, 95% CI 0.08-0.93; two studies) and fluoxetine (SMD 0.41, 95% CI 0.22-0.60; nine studies). There is insufficient evidence for the use of anti-Alzheimer drugs, anti-Parkinson drugs, CNS stimulants and piracetam to promote stroke recovery. CONCLUSIONS Administration of SSRIs may improve gross motor function, reduce disability and enhance QOL for patients recovering from stroke.
Collapse
Affiliation(s)
- See-Hwee Yeo
- Department of Pharmacy, Faculty of Science, National University of Singapore, 18 Science Drive 4, Singapore, 117543, Singapore
| | - Zheng-Jie Ian Lim
- Department of Pharmacy, Faculty of Science, National University of Singapore, 18 Science Drive 4, Singapore, 117543, Singapore
| | - Jia Mao
- Department of Pharmacy, Faculty of Science, National University of Singapore, 18 Science Drive 4, Singapore, 117543, Singapore
| | - Wai-Ping Yau
- Department of Pharmacy, Faculty of Science, National University of Singapore, 18 Science Drive 4, Singapore, 117543, Singapore.
| |
Collapse
|
52
|
Xu X, Bass B, McKillop WM, Mailloux J, Liu T, Geremia NM, Hryciw T, Brown A. Sox9 knockout mice have improved recovery following stroke. Exp Neurol 2018; 303:59-71. [DOI: 10.1016/j.expneurol.2018.02.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 12/13/2017] [Accepted: 02/04/2018] [Indexed: 12/17/2022]
|
53
|
Abstract
Rewiring is a plasticity mechanism that alters connectivity between neurons. Evidence for rewiring has been difficult to obtain. New evidence indicates that local circuitry is rewired during learning. Harnessing rewiring offers new ways to treat psychiatric and neurological diseases.
Neuronal connections form the physical basis for communication in the brain. Recently, there has been much interest in mapping the “connectome” to understand how brain structure gives rise to brain function, and ultimately, to behaviour. These attempts to map the connectome have largely assumed that connections are stable once formed. Recent studies, however, indicate that connections in mammalian brains may undergo rewiring during learning and experience-dependent plasticity. This suggests that the connectome is more dynamic than previously thought. To what extent can neural circuitry be rewired in the healthy adult brain? The connectome has been subdivided into multiple levels of scale, from synapses and microcircuits through to long-range tracts. Here, we examine the evidence for rewiring at each level. We then consider the role played by rewiring during learning. We conclude that harnessing rewiring offers new avenues to treat brain diseases.
Collapse
Affiliation(s)
- Sophie H Bennett
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE5 8AF, UK
| | - Alastair J Kirby
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE5 8AF, UK
| | - Gerald T Finnerty
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE5 8AF, UK.
| |
Collapse
|
54
|
Proteolytic Remodeling of Perineuronal Nets: Effects on Synaptic Plasticity and Neuronal Population Dynamics. Neural Plast 2018. [PMID: 29531525 PMCID: PMC5817213 DOI: 10.1155/2018/5735789] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The perineuronal net (PNN) represents a lattice-like structure that is prominently expressed along the soma and proximal dendrites of parvalbumin- (PV-) positive interneurons in varied brain regions including the cortex and hippocampus. It is thus apposed to sites at which PV neurons receive synaptic input. Emerging evidence suggests that changes in PNN integrity may affect glutamatergic input to PV interneurons, a population that is critical for the expression of synchronous neuronal population discharges that occur with gamma oscillations and sharp-wave ripples. The present review is focused on the composition of PNNs, posttranslation modulation of PNN components by sulfation and proteolysis, PNN alterations in disease, and potential effects of PNN remodeling on neuronal plasticity at the single-cell and population level.
Collapse
|
55
|
Li YY, Zhang B, Yu KW, Li C, Xie HY, Bao WQ, Kong YY, Jiao FY, Guan YH, Bai YL. Effects of constraint-induced movement therapy on brain glucose metabolism in a rat model of cerebral ischemia: a micro PET/CT study. Int J Neurosci 2018; 128:736-745. [PMID: 29251083 DOI: 10.1080/00207454.2017.1418343] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Ying-Ying Li
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Bei Zhang
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Ke-Wei Yu
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Ce Li
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Hong-Yu Xie
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Wei-Qi Bao
- Center, Department of Nuclear Medicine, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yan-Yan Kong
- Center, Department of Nuclear Medicine, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Fang-Yang Jiao
- Center, Department of Nuclear Medicine, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yi-Hui Guan
- Center, Department of Nuclear Medicine, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yu-Long Bai
- Department of Rehabilitation Medicine, Huashan Hospital, Fudan University, Shanghai, China
| |
Collapse
|
56
|
Modulation of Post-Stroke Plasticity and Regeneration by Stem Cell Therapy and Exogenic Factors. CELLULAR AND MOLECULAR APPROACHES TO REGENERATION AND REPAIR 2018. [DOI: 10.1007/978-3-319-66679-2_7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
57
|
Lake EMR, Bazzigaluppi P, Stefanovic B. Functional magnetic resonance imaging in chronic ischaemic stroke. Philos Trans R Soc Lond B Biol Sci 2017; 371:rstb.2015.0353. [PMID: 27574307 DOI: 10.1098/rstb.2015.0353] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/01/2016] [Indexed: 11/12/2022] Open
Abstract
Ischaemic stroke is the leading cause of adult disability worldwide. Effective rehabilitation is hindered by uncertainty surrounding the underlying mechanisms that govern long-term ischaemic injury progression. Despite its potential as a sensitive non-invasive in vivo marker of brain function that may aid in the development of new treatments, blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) has found limited application in the clinical research on chronic stage stroke progression. Stroke affects each of the physiological parameters underlying the BOLD contrast, markedly complicating the interpretation of BOLD fMRI data. This review summarizes current progress on application of BOLD fMRI in the chronic stage of ischaemic injury progression and discusses means by which more information may be gained from such BOLD fMRI measurements. Concomitant measurements of vascular reactivity, neuronal activity and metabolism in preclinical models of stroke are reviewed along with illustrative examples of post-ischaemic evolution in neuronal, glial and vascular function. The realization of the BOLD fMRI potential to propel stroke research is predicated on the carefully designed preclinical research establishing an ischaemia-specific quantitative model of BOLD signal contrast to provide the framework for interpretation of fMRI findings in clinical populations.This article is part of the themed issue 'Interpreting BOLD: a dialogue between cognitive and cellular neuroscience'.
Collapse
Affiliation(s)
- Evelyn M R Lake
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Paolo Bazzigaluppi
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada Fundamental Neurobiology, Krembil Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Bojana Stefanovic
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario, Canada Heart and Stroke Foundation Centre for Stroke Recovery, Ottawa, Canada
| |
Collapse
|
58
|
Schönfeld LM, Dooley D, Jahanshahi A, Temel Y, Hendrix S. Evaluating rodent motor functions: Which tests to choose? Neurosci Biobehav Rev 2017; 83:298-312. [PMID: 29107829 DOI: 10.1016/j.neubiorev.2017.10.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 09/18/2017] [Accepted: 10/23/2017] [Indexed: 01/11/2023]
Abstract
Damage to the motor cortex induced by stroke or traumatic brain injury (TBI) can result in chronic motor deficits. For the development and improvement of therapies, animal models which possess symptoms comparable to the clinical population are used. However, the use of experimental animals raises valid ethical and methodological concerns. To decrease discomfort by experimental procedures and to increase the quality of results, non-invasive and sensitive rodent motor tests are needed. A broad variety of rodent motor tests are available to determine deficits after stroke or TBI. The current review describes and evaluates motor tests that fall into three categories: Tests to evaluate fine motor skills and grip strength, tests for gait and inter-limb coordination and neurological deficit scores. In this review, we share our thoughts on standardized data presentation to increase data comparability between studies. We also critically evaluate current methods and provide recommendations for choosing the best behavioral test for a new research line.
Collapse
Affiliation(s)
- Lisa-Maria Schönfeld
- Comparative Psychology, Institute of Experimental Psychology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany.
| | - Dearbhaile Dooley
- Health Science Centre, School of Medicine, University College Dublin, Belfield, Dublin, Ireland
| | - Ali Jahanshahi
- Department of Neuroscience, Maastricht University, Maastricht, the Netherlands
| | - Yasin Temel
- Department of Neuroscience, Maastricht University, Maastricht, the Netherlands; Department of Neurosurgery, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Sven Hendrix
- Department of Morphology, Biomedical Research Institute (BIOMED), Hasselt University, Hasselt, Belgium.
| |
Collapse
|
59
|
Venkat P, Shen Y, Chopp M, Chen J. Cell-based and pharmacological neurorestorative therapies for ischemic stroke. Neuropharmacology 2017; 134:310-322. [PMID: 28867364 DOI: 10.1016/j.neuropharm.2017.08.036] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 08/22/2017] [Accepted: 08/24/2017] [Indexed: 01/09/2023]
Abstract
Ischemic stroke remains one of most common causes of death and disability worldwide. Stroke triggers a cascade of events leading to rapid neuronal damage and death. Neuroprotective agents that showed promise in preclinical experiments have failed to translate to the clinic. Even after decades of research, tPA remains the only FDA approved drug for stroke treatment. However, tPA is effective when administered 3-4.5 h after stroke onset and the vast majority of stroke patients do not receive tPA therapy. Therefore, there is a pressing need for novel therapies for ischemic stroke. Since stroke induces rapid cell damage and death, neuroprotective strategies that aim to salvage or replace injured brain tissue are challenged by treatment time frames. To overcome the barriers of neuroprotective therapies, there is an increasing focus on neurorestorative therapies for stroke. In this review article, we provide an update on neurorestorative treatments for stroke using cell therapy such as bone marrow derived mesenchymal stromal cells (BMSCs), human umbilical cord blood cells (HUCBCs) and select pharmacological approaches including Minocycline and Candesartan that have been employed in clinical trials. This review article discusses the present understanding of mechanisms of neurorestorative therapies and summarizes ongoing clinical trials. This article is part of the Special Issue entitled 'Cerebral Ischemia'.
Collapse
Affiliation(s)
- Poornima Venkat
- Department of Neurology, Henry Ford Hospital, Detroit, MI, 48202, USA
| | - Yi Shen
- Department of Neurology, Henry Ford Hospital, Detroit, MI, 48202, USA; Gerontology Institute, Department of Neurology, Tianjin Medical University General Hospital, Tianjin Neurological Institute, Key Laboratory of Post-Neurotrauma Neurorepair and Regeneration in Central Nervous System, Ministry of Education and Tianjin City, Tianjin, 300052, China
| | - Michael Chopp
- Department of Neurology, Henry Ford Hospital, Detroit, MI, 48202, USA; Department of Physics, Oakland University, Rochester, MI, 48309, USA
| | - Jieli Chen
- Department of Neurology, Henry Ford Hospital, Detroit, MI, 48202, USA; Gerontology Institute, Department of Neurology, Tianjin Medical University General Hospital, Tianjin Neurological Institute, Key Laboratory of Post-Neurotrauma Neurorepair and Regeneration in Central Nervous System, Ministry of Education and Tianjin City, Tianjin, 300052, China.
| |
Collapse
|
60
|
Otero-Ortega L, Gómez-de Frutos MC, Laso-García F, Sánchez-Gonzalo A, Martínez-Arroyo A, Díez-Tejedor E, Gutiérrez-Fernández M. NogoA Neutralization Promotes Axonal Restoration After White Matter Injury In Subcortical Stroke. Sci Rep 2017; 7:9431. [PMID: 28842591 PMCID: PMC5573364 DOI: 10.1038/s41598-017-09705-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 07/27/2017] [Indexed: 12/19/2022] Open
Abstract
Blocking axonal growth inhibitor NogoA has been of great interest for promoting axonal recovery from neurological diseases. The present study investigates the therapeutic effects of blocking NogoA, inducing functional recovery and promoting white matter repair in an experimental animal model of stroke. Adult male rats were subjected to white matter injury by subcortical ischemic stroke. Twenty-four hours after surgery, 250 ug of anti-NogoA or anti-IgG-1 were administered through the tail vein. The quantity of NogoA protein was determined by immunohistochemistry in the brain and peripheral organs. In addition, functional status, lesion size, fiber tract integrity, axonal sprouting and white matter repair markers were analyzed. Moreover, an in vitro study was performed in order to strengthen the results obtained in vivo. A lower quantity of NogoA protein was found in the brain and peripheral organs of the animals that received anti-NogoA treatment. The animals receiving anti-NogoA treatment showed significantly better results in terms of functional recovery, fiber tract integrity, axonal sprouting and white matter repair markers compared with the control group at 28 days. White matter integrity was in part restored by antibody-mediated inhibition of NogoA administration in those animals that were subjected to an axonal injury by subcortical stroke. This white matter restoration triggered functional recovery.
Collapse
Affiliation(s)
- Laura Otero-Ortega
- Neuroscience and Cerebrovascular Research Laboratory, Department of Neurology and Stroke Center, La Paz University Hospital, Neuroscience Area of IdiPAZ Health Research Institute, Autonomous University of Madrid, Madrid, Spain
| | - Mari Carmen Gómez-de Frutos
- Neuroscience and Cerebrovascular Research Laboratory, Department of Neurology and Stroke Center, La Paz University Hospital, Neuroscience Area of IdiPAZ Health Research Institute, Autonomous University of Madrid, Madrid, Spain
| | - Fernando Laso-García
- Neuroscience and Cerebrovascular Research Laboratory, Department of Neurology and Stroke Center, La Paz University Hospital, Neuroscience Area of IdiPAZ Health Research Institute, Autonomous University of Madrid, Madrid, Spain
| | - Alba Sánchez-Gonzalo
- Neuroscience and Cerebrovascular Research Laboratory, Department of Neurology and Stroke Center, La Paz University Hospital, Neuroscience Area of IdiPAZ Health Research Institute, Autonomous University of Madrid, Madrid, Spain
| | - Arturo Martínez-Arroyo
- Neuroscience and Cerebrovascular Research Laboratory, Department of Neurology and Stroke Center, La Paz University Hospital, Neuroscience Area of IdiPAZ Health Research Institute, Autonomous University of Madrid, Madrid, Spain
| | - Exuperio Díez-Tejedor
- Neuroscience and Cerebrovascular Research Laboratory, Department of Neurology and Stroke Center, La Paz University Hospital, Neuroscience Area of IdiPAZ Health Research Institute, Autonomous University of Madrid, Madrid, Spain.
| | - María Gutiérrez-Fernández
- Neuroscience and Cerebrovascular Research Laboratory, Department of Neurology and Stroke Center, La Paz University Hospital, Neuroscience Area of IdiPAZ Health Research Institute, Autonomous University of Madrid, Madrid, Spain.
| |
Collapse
|
61
|
Liu T, Li J, Huang S, Li C, Zhao Z, Wen G, Chen F. Altered resting-state functional activity in isolated pontine infarction patients with pathological laughing and crying. Oncotarget 2017; 8:84529-84539. [PMID: 29137445 PMCID: PMC5663617 DOI: 10.18632/oncotarget.19307] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 06/24/2017] [Indexed: 12/11/2022] Open
Abstract
We used resting-state functional magnetic resonance imaging to investigate the global spontaneous neural activity involved in pathological laughing and crying after stroke. Twelve pathological laughing and crying patients with isolated pontine infarction were included, along with 12 age- and gender-matched acute isolated pontine infarction patients without pathological laughing and crying, and 12 age- and gender-matched healthy controls. We examined both the amplitude of low-frequency fluctuation and the regional homogeneity in order to comprehensively evaluate the intrinsic activity in patients with post-stroke pathological laughing and crying. In the post-stroke pathological laughing and crying group, changes in these measures were observed mainly in components of the default mode network (medial prefrontal cortex/anterior cingulate cortex, middle temporal gyrus, inferior temporal gyrus, superior frontal gyrus, middle frontal gyrus and inferior parietal lobule), sensorimotor network (supplementary motor area, precentral gyrus and paracentral lobule), affective network (medial prefrontal cortex/anterior cingulate cortex, parahippocampal gyrus, middle temporal gyrus and inferior temporal gyrus) and cerebellar lobes (cerebellum posterior lobe). We therefore speculate that when disinhibition of the volitional system is lost, increased activation of the emotional system causes pathological laughing and crying.
Collapse
Affiliation(s)
- Tao Liu
- Department of Neurology, Hainan General Hospital, Haikou 570311, China
| | - Jianjun Li
- Department of Radiology, Hainan General Hospital, Haikou 570311, China
| | - Shixiong Huang
- Department of Neurology, Hainan General Hospital, Haikou 570311, China
| | - Changqinq Li
- Department of Radiology, Hainan General Hospital, Haikou 570311, China
| | - Zhongyan Zhao
- Department of Neurology, Hainan General Hospital, Haikou 570311, China
| | - Guoqiang Wen
- Department of Neurology, Hainan General Hospital, Haikou 570311, China
| | - Feng Chen
- Department of Radiology, Hainan General Hospital, Haikou 570311, China
| |
Collapse
|
62
|
Tennant KA, Taylor SL, White ER, Brown CE. Optogenetic rewiring of thalamocortical circuits to restore function in the stroke injured brain. Nat Commun 2017. [PMID: 28643802 PMCID: PMC5490053 DOI: 10.1038/ncomms15879] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
To regain sensorimotor functions after stroke, surviving neural circuits must reorganize and form new connections. Although the thalamus is critical for processing and relaying sensory information to the cortex, little is known about how stroke affects the structure and function of these connections, or whether a therapeutic approach targeting these circuits can improve recovery. Here we reveal with in vivo calcium imaging that stroke in somatosensory cortex dampens the excitability of surviving thalamocortical circuits. Given this deficit, we hypothesized that chronic transcranial window optogenetic stimulation of thalamocortical axons could facilitate recovery. Using two-photon imaging, we show that optogenetic stimulation promotes the formation of new and stable thalamocortical synaptic boutons, without impacting axon branch dynamics. Stimulation also enhances the recovery of somatosensory cortical circuit function and forepaw sensorimotor abilities. These results demonstrate that an optogenetic approach can rewire thalamocortical circuits and restore function in the damaged brain. Stroke recovery requires circuit reorganization and therapeutic efforts have focused on rewiring cortical circuits after stroke, but what about thalamic inputs? Here, the authors examine how thalamocortical axons are affected by stroke and use optogenetic stimulation to promote recovery.
Collapse
Affiliation(s)
- Kelly A Tennant
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada V8P 5C2
| | - Stephanie L Taylor
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada V8P 5C2
| | - Emily R White
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada V8P 5C2
| | - Craig E Brown
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada V8P 5C2.,Department of Biology, University of Victoria, Victoria, British Columbia, Canada V8P 5C2.,Department of Psychiatry, University of British Columbia, Vancouver, British Columbia, Canada
| |
Collapse
|
63
|
Jung WB, Han YH, Chung JJ, Chae SY, Lee SH, Im GH, Cha J, Lee JH. Spatiotemporal microstructural white matter changes in diffusion tensor imaging after transient focal ischemic stroke in rats. NMR IN BIOMEDICINE 2017; 30:e3704. [PMID: 28205341 DOI: 10.1002/nbm.3704] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 11/18/2016] [Accepted: 01/07/2017] [Indexed: 06/06/2023]
Abstract
Structural reorganization in white matter (WM) after stroke is a potential contributor to substitute or to newly establish the functional field on the injured brain in nature. Diffusion tensor imaging (DTI) is an imaging modality that can be used to evaluate damage and recovery within the brain. This method of imaging allows for in vivo assessment of the restricted movements of water molecules in WM and provides a detailed look at structural connectivity in the brain. For longitudinal DTI studies after a stroke, the conventional region of interest method and voxel-based analysis are highly dependent on the user-hypothesis and parameter settings for implementation. In contrast, tract-based spatial statistics (TBSS) allows for reliable voxel-wise analysis via the projection of diffusion-derived parameters onto an alignment-invariant WM skeleton. In this study, spatiotemporal WM changes were examined with DTI-derived parameters (fractional anisotropy, FA; mean diffusivity, MD; axial diffusivity, DA; radial diffusivity, RD) using TBSS 2 h to 6 weeks after experimental focal ischemic stroke in rats (N = 6). FA values remained unchanged 2-4 h after the stroke, followed by a continuous decrease in the ipsilesional hemisphere from 24 h to 2 weeks post-stroke and gradual recovery from the ipsilesional corpus callosum to the external capsule until 6 weeks post-stroke. In particular, the fibers in these areas were extended toward the striatum of the ischemic boundary region at 6 weeks on tractography. The alterations of the other parameters in the ipsilesional hemisphere showed patterns of a decrease at the early stage, a subsequent pseudo-normalization of MD and DA, a rapid reduction of RD, and a progressive increase in MD, DA and RD with a decreased extent in the injured area at later stages. The findings of this study may reflect the ongoing processes on tissue damage and spontaneous recovery after stroke.
Collapse
Affiliation(s)
- Won-Beom Jung
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- Center for NeuroScience Imaging Research, Institute for Basic Science (IBS), Suwon, Korea
| | - Yong Hee Han
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Julius Juhyun Chung
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- Center for NeuroScience Imaging Research, Institute for Basic Science (IBS), Suwon, Korea
- Samsung Advanced Institute of Health Science and Technology, Sungkyunkwan University, Seoul, Korea
| | - Sun Young Chae
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- Center for NeuroScience Imaging Research, Institute for Basic Science (IBS), Suwon, Korea
- Samsung Advanced Institute of Health Science and Technology, Sungkyunkwan University, Seoul, Korea
| | - Sung Hoon Lee
- Department of Medicine, Kyungpook National University, School of Medicine, Daegu, Korea
- Center for Molecular and Cellular Imaging, Samsung Biomedical Research Institute, Seoul, Korea
| | - Geun Ho Im
- Center for Molecular and Cellular Imaging, Samsung Biomedical Research Institute, Seoul, Korea
| | - JiHoon Cha
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jung Hee Lee
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- Center for NeuroScience Imaging Research, Institute for Basic Science (IBS), Suwon, Korea
- Samsung Advanced Institute of Health Science and Technology, Sungkyunkwan University, Seoul, Korea
| |
Collapse
|
64
|
Pan R, Cai J, Zhan L, Guo Y, Huang RY, Li X, Zhou M, Xu D, Zhan J, Chen H. Buyang Huanwu decoction facilitates neurorehabilitation through an improvement of synaptic plasticity in cerebral ischemic rats. Altern Ther Health Med 2017; 17:173. [PMID: 28351388 PMCID: PMC5371213 DOI: 10.1186/s12906-017-1680-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 03/11/2017] [Indexed: 12/21/2022]
Abstract
BACKGROUND Loss of neural function is a critical but unsolved issue after cerebral ischemia insult. Neuronal plasticity and remodeling are crucial for recovery of neural functions after brain injury. Buyang Huanwu decoction, which is a classic formula in traditional Chinese medicine, can positively alter synaptic plasticity. This study assessed the effects of Buyang Huanwu decoction in combination with physical exercise on neuronal plasticity in cerebral ischemic rats. METHODS Cerebral ischemic rats were administered Buyang Huanwu decoction and participated in physical exercise after the induction of a permanent middle cerebral artery occlusion. The neurobehavioral functions and infarct volumes were evaluated. The presynaptic (SYN), postsynaptic (GAP-43) and cytoskeletal (MAP-2) proteins in the coronal brain samples were evaluated by immunohistochemistry and western blot analyses. The ultrastructure of the neuronal synaptic junctions in the same region were analyzed using transmission electron microscopy. RESULTS Combination treatment of Buyang Huanwu decoction and physical exercise ameliorated the neurobehavioral deficits (p < 0.05), significantly enhanced the expression levels of SYN, GAP-43 and MAP-2 (p < 0.05), and maintained the synaptic ultrastructure. CONCLUSIONS Buyang Huanwu decoction facilitated neurorehabilitation following a cerebral ischemia insult through an improvement in synaptic plasticity. Graphical abstract The Buyang Huanwu decoction (BYHWD) combined with physical exercise (PE) attenuates synaptic disruption and promotes synaptic plasticity following cerebral ischemia (stroke).
Collapse
|
65
|
Parker K, Berretta A, Saenger S, Sivaramakrishnan M, Shirley SA, Metzger F, Clarkson AN. PEGylated insulin-like growth factor-I affords protection and facilitates recovery of lost functions post-focal ischemia. Sci Rep 2017; 7:241. [PMID: 28325900 PMCID: PMC5428211 DOI: 10.1038/s41598-017-00336-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 02/21/2017] [Indexed: 12/04/2022] Open
Abstract
Insulin-like growth factor-I (IGF-I) is involved in the maturation and maintenance of neurons, and impaired IGF-I signaling has been shown to play a role in various neurological diseases including stroke. The aim of the present study was to investigate the efficacy of an optimized IGF-I variant by adding a 40 kDa polyethylene glycol (PEG) chain to IGF-I to form PEG-IGF-I. We show that PEG-IGF-I has a slower clearance which allows for twice-weekly dosing to maintain steady-state serum levels in mice. Using a photothrombotic model of focal stroke, dosing from 3 hrs post-stroke dose-dependently (0.3–1 mg/kg) decreases the volume of infarction and improves motor behavioural function in both young 3-month and aged 22–24 month old mice. Further, PEG-IGF-I treatment increases GFAP expression when given early (3 hrs post-stroke), increases Synaptophysin expression and increases neurogenesis in young and aged. Finally, neurons (P5–6) cultured in vitro on reactive astrocytes in the presence of PEG-IGF-I showed an increase in neurite length, indicating that PEG-IGF-I can aid in sprouting of new connections. This data suggests a modulatory role of IGF-I in both protective and regenerative processes, and indicates that therapeutic approaches using PEG-IGF-I should be given early and where the endogenous regenerative potential is still high.
Collapse
Affiliation(s)
- Kim Parker
- Department of Anatomy and Brain Health Research Center, University of Otago, Dunedin 9054, New Zealand
| | - Antonio Berretta
- Department of Anatomy and Brain Health Research Center, University of Otago, Dunedin 9054, New Zealand
| | - Stefanie Saenger
- F. Hoffmann-La Roche Ltd., pRED, Pharma Research & Early Development, Roche Innovation Center Basel, Grenzacherstrasse 124, CH-4070, Basel, Switzerland
| | - Manaswini Sivaramakrishnan
- F. Hoffmann-La Roche Ltd., pRED, Pharma Research & Early Development, Roche Innovation Center Basel, Grenzacherstrasse 124, CH-4070, Basel, Switzerland
| | - Simon A Shirley
- Department of Anatomy and Brain Health Research Center, University of Otago, Dunedin 9054, New Zealand
| | - Friedrich Metzger
- F. Hoffmann-La Roche Ltd., pRED, Pharma Research & Early Development, Roche Innovation Center Basel, Grenzacherstrasse 124, CH-4070, Basel, Switzerland
| | - Andrew N Clarkson
- Department of Anatomy and Brain Health Research Center, University of Otago, Dunedin 9054, New Zealand. .,Brain Research New Zealand, University of Otago, Dunedin 9054, New Zealand. .,Faculty of Pharmacy, The University of Sydney, Sydney, Australia.
| |
Collapse
|
66
|
Alia C, Spalletti C, Lai S, Panarese A, Lamola G, Bertolucci F, Vallone F, Di Garbo A, Chisari C, Micera S, Caleo M. Neuroplastic Changes Following Brain Ischemia and their Contribution to Stroke Recovery: Novel Approaches in Neurorehabilitation. Front Cell Neurosci 2017; 11:76. [PMID: 28360842 PMCID: PMC5352696 DOI: 10.3389/fncel.2017.00076] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 03/03/2017] [Indexed: 12/21/2022] Open
Abstract
Ischemic damage to the brain triggers substantial reorganization of spared areas and pathways, which is associated with limited, spontaneous restoration of function. A better understanding of this plastic remodeling is crucial to develop more effective strategies for stroke rehabilitation. In this review article, we discuss advances in the comprehension of post-stroke network reorganization in patients and animal models. We first focus on rodent studies that have shed light on the mechanisms underlying neuronal remodeling in the perilesional area and contralesional hemisphere after motor cortex infarcts. Analysis of electrophysiological data has demonstrated brain-wide alterations in functional connectivity in both hemispheres, well beyond the infarcted area. We then illustrate the potential use of non-invasive brain stimulation (NIBS) techniques to boost recovery. We finally discuss rehabilitative protocols based on robotic devices as a tool to promote endogenous plasticity and functional restoration.
Collapse
Affiliation(s)
- Claudia Alia
- CNR Neuroscience Institute, National Research Council (CNR)Pisa, Italy; Laboratory of Biology, Scuola Normale SuperiorePisa, Italy
| | | | - Stefano Lai
- Translational Neural Engineering Area, The BioRobotics Institute, Scuola Superiore Sant'Anna Pontedera, Italy
| | - Alessandro Panarese
- Translational Neural Engineering Area, The BioRobotics Institute, Scuola Superiore Sant'Anna Pontedera, Italy
| | - Giuseppe Lamola
- Department of Neuroscience, Unit of Neurorehabilitation-University Hospital of Pisa Pisa, Italy
| | - Federica Bertolucci
- Department of Neuroscience, Unit of Neurorehabilitation-University Hospital of Pisa Pisa, Italy
| | - Fabio Vallone
- Translational Neural Engineering Area, The BioRobotics Institute, Scuola Superiore Sant'AnnaPontedera, Italy; CNR Biophysics Institute, National Research Council (CNR)Pisa, Italy; Neural Computation Laboratory, Center for Neuroscience and Cognitive Systems @UniTn, Italian institute of Technology (IIT)Rovereto, Italy
| | - Angelo Di Garbo
- CNR Biophysics Institute, National Research Council (CNR) Pisa, Italy
| | - Carmelo Chisari
- Department of Neuroscience, Unit of Neurorehabilitation-University Hospital of Pisa Pisa, Italy
| | - Silvestro Micera
- Translational Neural Engineering Area, The BioRobotics Institute, Scuola Superiore Sant'AnnaPontedera, Italy; Ecole Polytechnique Federale de Lausanne (EPFL), Bertarelli Foundation Chair in Translational NeuroEngineering Laboratory, Center for Neuroprosthetics and Institute of BioengineeringLausanne, Switzerland
| | - Matteo Caleo
- CNR Neuroscience Institute, National Research Council (CNR) Pisa, Italy
| |
Collapse
|
67
|
Zhao CC, Wang CF, Li WP, Lin Y, Tang QL, Feng JF, Mao Q, Gao GY, Jiang JY. Mild Hypothermia Promotes Pericontusion Neuronal Sprouting via Suppressing Suppressor of Cytokine Signaling 3 Expression after Moderate Traumatic Brain Injury. J Neurotrauma 2017; 34:1636-1644. [PMID: 27923323 DOI: 10.1089/neu.2016.4759] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Mild therapeutic hypothermia is a candidate for the treatment of traumatic brain injury (TBI). However, the role of mild hypothermia in neuronal sprouting after TBI remains obscure. We used a fluid percussion injury (FPI) model to assess the effect of mild hypothermia on pericontusion neuronal sprouting after TBI in rats. Male Sprague-Dawley rats underwent FPI or sham surgery, followed by mild hypothermia treatment (33°C) or normothermia treatment (37°C) for 3 h. All the rats were euthanized at 7 days after FPI. Neuronal sprouting that was confirmed by an increase in growth associated protein-43 (GAP-43) expression was evaluated using immunofluorescence and Western blot assays. The expression levels of several intrinsic and extrinsic sprouting-associated genes such as neurite outgrowth inhibitor A (NogoA), phosphatase and tensin homolog (PTEN), and suppressor of cytokine signaling 3 (SOCS3) were analyzed by quantitative real-time polymerase chain reaction (RT-PCR). Our results revealed that mild hypothermia significantly increased the expression level of GAP-43 and dramatically suppressed the expression level of interleukin-6 (IL-6) and SOCS3 at 7 days after FPI in the ipsilateral cortex compared with that of the normothermia TBI group. These data suggest that post-traumatic mild hypothermia promotes pericontusion neuronal sprouting after TBI. Moreover, the mechanism of hypothermia-induced neuronal sprouting might be partially associated with decreased levels of SOCS3.
Collapse
Affiliation(s)
- Cheng-Cheng Zhao
- 1 Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Chuan-Fang Wang
- 1 Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Wei-Ping Li
- 2 Department of Neurosurgery, Shenzhen Second People's Hospital, Shenzhen University , Shenzhen, Guangdong, People's Republic of China
| | - Yong Lin
- 1 Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Qi-Lin Tang
- 1 Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Jun-Feng Feng
- 1 Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Qing Mao
- 1 Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Guo-Yi Gao
- 1 Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| | - Ji-Yao Jiang
- 1 Department of Neurosurgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai Institute of Head Trauma, Shanghai, People's Republic of China
| |
Collapse
|
68
|
Funck T, Al‐Kuwaiti M, Lepage C, Zepper P, Minuk J, Schipper HM, Evans AC, Thiel A. Assessing neuronal density in peri-infarct cortex with PET: Effects of cortical topology and partial volume correction. Hum Brain Mapp 2017; 38:326-338. [PMID: 27614005 PMCID: PMC6866936 DOI: 10.1002/hbm.23363] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 08/05/2016] [Accepted: 08/18/2016] [Indexed: 01/02/2023] Open
Abstract
The peri-infarct cortex (PIC) is the site of long-term physiologic changes after ischemic stroke. Traditional methods for delineating the peri-infarct gray matter (GM) have used a volumetric Euclidean distance metric to define its extent around the infarct. This metric has limitations in the case of cortical stroke, i.e., those where ischemia leads to infarction in the cortical GM, because the vascularization of the cerebral cortex follows the complex, folded topology of the cortical surface. Instead, we used a geodesic distance metric along the cortical surface to subdivide the PIC into equidistant rings emanating from the infarct border and compared this new approach to a Euclidean distance metric definition. This was done in 11 patients with [F-18]-Flumazenil ([18-F]-FMZ) positron emission tomography (PET) scans at 2 weeks post-stroke and at 6 month follow-up. FMZ is a PET radiotracer with specific binding to the alpha subunits of the type A γ-aminobutyric acid (GABAA) receptor. Additionally, we used partial-volume correction (PVC) of the PET images to compensate for potential cortical thinning and long-term neuronal loss in follow-up images. The difference in non-displaceable binding potential (BPND ) between the stroke unaffected and affected hemispheres was 35% larger in the geodesic versus the Euclidean peri-infarct models in initial PET images and 48% larger in follow-up PET images. The inter-hemispheric BPND difference was approximately 17-20% larger after PVC when compared to uncorrected PET images. PET studies of peri-infarct GM in cortical strokes should use a geodesic model and include PVC as a preprocessing step. Hum Brain Mapp 38:326-338, 2017. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Thomas Funck
- Montreal Neurological Institute, McGill UniversityMontrealCanada
- Jewish General HospitalLady Davis InstituteMontrealCanada
| | - Mohammed Al‐Kuwaiti
- Montreal Neurological Institute, McGill UniversityMontrealCanada
- Jewish General HospitalLady Davis InstituteMontrealCanada
| | - Claude Lepage
- Montreal Neurological Institute, McGill UniversityMontrealCanada
| | - Peter Zepper
- Department of NeurologyTechnische Universität MünchenMunichGermany
| | - Jeffrey Minuk
- Jewish General HospitalLady Davis InstituteMontrealCanada
| | | | - Alan C. Evans
- Montreal Neurological Institute, McGill UniversityMontrealCanada
| | - Alexander Thiel
- Montreal Neurological Institute, McGill UniversityMontrealCanada
- Jewish General HospitalLady Davis InstituteMontrealCanada
| |
Collapse
|
69
|
Imaging the Transformation of Ipsilateral Internal Capsule Following Focal Cerebral Ischemia in Rat by Diffusion Kurtosis Imaging. J Stroke Cerebrovasc Dis 2017; 26:42-48. [DOI: 10.1016/j.jstrokecerebrovasdis.2016.08.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 08/05/2016] [Accepted: 08/17/2016] [Indexed: 12/13/2022] Open
|
70
|
Deng B, Bai F, Zhou H, Zhou D, Ma Z, Xiong L, Wang Q. Electroacupuncture enhances rehabilitation through miR-181b targeting PirB after ischemic stroke. Sci Rep 2016; 6:38997. [PMID: 27966582 PMCID: PMC5155251 DOI: 10.1038/srep38997] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 11/16/2016] [Indexed: 12/15/2022] Open
Abstract
Recent studies have demonstrated microRNAs (miRNAs) and proteins are beneficial to axon regeneration, which may be involved in Electroacupuncture (EA) therapy against stroke. In this study, we aimed to determine the pivotal role of PirB in EA-produced rehabilitation against ischemic stroke; and to screen and investigate the potential miRNAs directly regulating PirB expression. The results showed EA treatment enhanced axon regeneration and new projections from the corticospinal tract at 28 d after cerebral ischemic reperfusion injury of rats. Then, we found EA decreased pirb mRNA and PirB protein expression in the penumbra within 28 days after reperfusion. The reduction of PirB expression facilitated neurite outgrowth after oxygen-glucose deprivation injury. The miRNA microarray showed the level of twenty kinds of miRNAs changed in the penumbra after EA administration. The bioinformatics study and luciferase assay verified miR-181b directly regulated pirb mRNA expression. EA increased miR-181b levels in the penumbras, and improved neurobehavioral function rehabilitation through miR-181b direct targeting of pirb mRNA to regulate the expression of PirB, RhoA and GAP43. In conclusion, we provide the first evidence that EA enhances rehabilitation against stroke by regulating epigenetic changes to directly act on its targets, such as the miR-181b/PirB/RhoA/GAP43 axis, which is a novel mechanism of EA therapy.
Collapse
Affiliation(s)
- Bin Deng
- Department of Anesthesiology, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an 710061, China
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Oral Diseases, Department of Anesthesiology, School of Stomatology, Fourth Military Medical University, Xi’an 710032, China
| | - Fuhai Bai
- Department of Anesthesiology, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, China
| | - Heng Zhou
- Department of Anesthesiology, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, China
| | - Dandan Zhou
- Department of Anesthesiology, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, China
| | - Zhi Ma
- Department of Anesthesiology, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, China
| | - Lize Xiong
- Department of Anesthesiology, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, China
| | - Qiang Wang
- Department of Anesthesiology, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an 710061, China
- Department of Anesthesiology, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, China
| |
Collapse
|
71
|
Stokowska A, Atkins AL, Morán J, Pekny T, Bulmer L, Pascoe MC, Barnum SR, Wetsel RA, Nilsson JA, Dragunow M, Pekna M. Complement peptide C3a stimulates neural plasticity after experimental brain ischaemia. Brain 2016; 140:353-369. [PMID: 27956400 DOI: 10.1093/brain/aww314] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 10/19/2016] [Accepted: 10/20/2016] [Indexed: 11/12/2022] Open
Abstract
Ischaemic stroke induces endogenous repair processes that include proliferation and differentiation of neural stem cells and extensive rewiring of the remaining neural connections, yet about 50% of stroke survivors live with severe long-term disability. There is an unmet need for drug therapies to improve recovery by promoting brain plasticity in the subacute to chronic phase after ischaemic stroke. We previously showed that complement-derived peptide C3a regulates neural progenitor cell migration and differentiation in vitro and that C3a receptor signalling stimulates neurogenesis in unchallenged adult mice. To determine the role of C3a-C3a receptor signalling in ischaemia-induced neural plasticity, we subjected C3a receptor-deficient mice, GFAP-C3a transgenic mice expressing biologically active C3a in the central nervous system, and their respective wild-type controls to photothrombotic stroke. We found that C3a overexpression increased, whereas C3a receptor deficiency decreased post-stroke expression of GAP43 (P < 0.01), a marker of axonal sprouting and plasticity, in the peri-infarct cortex. To verify the translational potential of these findings, we used a pharmacological approach. Daily intranasal treatment of wild-type mice with C3a beginning 7 days after stroke induction robustly increased synaptic density (P < 0.01) and expression of GAP43 in peri-infarct cortex (P < 0.05). Importantly, the C3a treatment led to faster and more complete recovery of forepaw motor function (P < 0.05). We conclude that C3a-C3a receptor signalling stimulates post-ischaemic neural plasticity and intranasal treatment with C3a receptor agonists is an attractive approach to improve functional recovery after ischaemic brain injury.
Collapse
Affiliation(s)
- Anna Stokowska
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Alison L Atkins
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Javier Morán
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Tulen Pekny
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Linda Bulmer
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Michaela C Pascoe
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Scott R Barnum
- Department of Microbiology, University of Alabama, Birmingham, Alabama, USA
| | - Rick A Wetsel
- Research Center for Immunology and Autoimmune Diseases, Institute of Molecular Medicine for the Prevention of Human Diseases, University of Texas-Houston, Houston, Texas, USA
| | - Jonas A Nilsson
- Department of Surgery, Institute of Clinical Sciences, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
| | - Mike Dragunow
- Department of Pharmacology and Centre for Brain Research, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand
| | - Marcela Pekna
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden .,Florey Institute of Neuroscience and Mental Health, Parkville, Victoria, Australia.,Hunter Medical Research Institute, University of Newcastle, New South Wales, Australia
| |
Collapse
|
72
|
Robinson N, Zaidi AD, Rana M, Prasad VA, Guan C, Birbaumer N, Sitaram R. Real-Time Subject-Independent Pattern Classification of Overt and Covert Movements from fNIRS Signals. PLoS One 2016; 11:e0159959. [PMID: 27467528 PMCID: PMC4965045 DOI: 10.1371/journal.pone.0159959] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2016] [Accepted: 07/11/2016] [Indexed: 11/30/2022] Open
Abstract
Recently, studies have reported the use of Near Infrared Spectroscopy (NIRS) for developing Brain–Computer Interface (BCI) by applying online pattern classification of brain states from subject-specific fNIRS signals. The purpose of the present study was to develop and test a real-time method for subject-specific and subject-independent classification of multi-channel fNIRS signals using support-vector machines (SVM), so as to determine its feasibility as an online neurofeedback system. Towards this goal, we used left versus right hand movement execution and movement imagery as study paradigms in a series of experiments. In the first two experiments, activations in the motor cortex during movement execution and movement imagery were used to develop subject-dependent models that obtained high classification accuracies thereby indicating the robustness of our classification method. In the third experiment, a generalized classifier-model was developed from the first two experimental data, which was then applied for subject-independent neurofeedback training. Application of this method in new participants showed mean classification accuracy of 63% for movement imagery tasks and 80% for movement execution tasks. These results, and their corresponding offline analysis reported in this study demonstrate that SVM based real-time subject-independent classification of fNIRS signals is feasible. This method has important applications in the field of hemodynamic BCIs, and neuro-rehabilitation where patients can be trained to learn spatio-temporal patterns of healthy brain activity.
Collapse
Affiliation(s)
- Neethu Robinson
- School of Computer Science and Engineering, Nanyang Technological University, Singapore, Singapore
| | - Ali Danish Zaidi
- Max Planck Institute for Biological Cybernetics, Tuebingen, Germany
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tuebingen, Germany
- * E-mail: (RS); (ADZ)
| | - Mohit Rana
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tuebingen, Germany
| | - Vinod A. Prasad
- School of Computer Science and Engineering, Nanyang Technological University, Singapore, Singapore
| | - Cuntai Guan
- School of Computer Science and Engineering, Nanyang Technological University, Singapore, Singapore
- Department of Neural and Biomedical Technology, Institute for Infocomm Research, A*STAR, Singapore, Singapore
| | - Niels Birbaumer
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tuebingen, Germany
- Wyss Center for Bio and Neuroengineering, Geneva, Switzerland
| | - Ranganatha Sitaram
- School of Computer Science and Engineering, Nanyang Technological University, Singapore, Singapore
- Max Planck Institute for Biological Cybernetics, Tuebingen, Germany
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tuebingen, Germany
- Department of Psychiatry and Division of Neuroscience, Schools of Engineering, Biology & Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
- * E-mail: (RS); (ADZ)
| |
Collapse
|
73
|
Protein Synthesis Inhibition in the Peri-Infarct Cortex Slows Motor Recovery in Rats. PLoS One 2016; 11:e0157859. [PMID: 27314672 PMCID: PMC4912164 DOI: 10.1371/journal.pone.0157859] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 06/06/2016] [Indexed: 12/02/2022] Open
Abstract
Neuroplasticity and reorganization of brain motor networks are thought to enable recovery of motor function after ischemic stroke. Especially in the cortex surrounding the ischemic scar (i.e., peri-infarct cortex), evidence for lasting reorganization has been found at the level of neurons and networks. This reorganization depends on expression of specific genes and subsequent protein synthesis. To test the functional relevance of the peri-infarct cortex for recovery we assessed the effect of protein synthesis inhibition within this region after experimental stroke. Long-Evans rats were trained to perform a skilled-reaching task (SRT) until they reached plateau performance. A photothrombotic stroke was induced in the forelimb representation of the primary motor cortex (M1) contralateral to the trained paw. The SRT was re-trained after stroke while the protein synthesis inhibitor anisomycin (ANI) or saline were injected into the peri-infarct cortex through implanted cannulas. ANI injections reduced protein synthesis within the peri-infarct cortex by 69% and significantly impaired recovery of reaching performance through re-training. Improvement of motor performance within a single training session remained intact, while improvement between training sessions was impaired. ANI injections did not affect infarct size. Thus, protein synthesis inhibition within the peri-infarct cortex impairs recovery of motor deficits after ischemic stroke by interfering with consolidation of motor memory between training sessions but not short-term improvements within one session.
Collapse
|
74
|
Kassis H, Shehadah A, Li C, Zhang Y, Cui Y, Roberts C, Sadry N, Liu X, Chopp M, Zhang ZG. Class IIa histone deacetylases affect neuronal remodeling and functional outcome after stroke. Neurochem Int 2016; 96:24-31. [PMID: 27103167 DOI: 10.1016/j.neuint.2016.04.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 04/11/2016] [Accepted: 04/16/2016] [Indexed: 01/09/2023]
Abstract
We have previously demonstrated that stroke induces nuclear shuttling of class IIa histone deacetylase 4 (HDAC4). Stroke-induced nuclear shuttling of HDAC4 is positively and significantly correlated with improved indices of neuronal remodeling in the peri-infarct cortex. In this study, using a rat model for middle cerebral artery occlusion (MCAO), we tested the effects of selective inhibition of class IIa HDACs on functional recovery and neuronal remodeling when administered 24hr after stroke. Adult male Wistar rats (n = 15-17/group) were subjected to 2 h MCAO and orally gavaged with MC1568 (a selective class IIa HDAC inhibitor), SAHA (a non-selective HDAC inhibitor), or vehicle-control for 7 days starting 24 h after MCAO. A battery of behavioral tests was performed. Lesion volume measurement and immunohistochemistry were performed 28 days after MCAO. We found that stroke increased total HDAC activity in the ipsilateral hemisphere compared to the contralateral hemisphere. Stroke-increased HDAC activity was significantly decreased by the administration of SAHA as well as by MC1568. However, SAHA significantly improved functional outcome compared to vehicle control, whereas selective class IIa inhibition with MC1568 increased mortality and lesion volume and did not improve functional outcome. In addition, MC1568 decreased microtubule associated protein 2 (MAP2, dendrites), phosphorylated neurofilament heavy chain (pNFH, axons) and myelin basic protein (MBP, myelination) immunoreactivity in the peri-infarct cortex. Quantitative RT-PCR of cortical neurons isolated by laser capture microdissection revealed that MC1568, but not SAHA, downregulated CREB and c-fos expression. Additionally, MC1568 decreased the expression of phosphorylated CREB (active) in neurons. Taken together, these findings demonstrate that selective inhibition of class IIa HDACs impairs neuronal remodeling and neurological outcome. Inactivation of CREB and c-fos by MC1568 likely contributes to this detrimental effect.
Collapse
Affiliation(s)
- Haifa Kassis
- Department of Neurology, Henry Ford Health System, Detroit, MI 48202, USA
| | - Amjad Shehadah
- Department of Neurology, Henry Ford Health System, Detroit, MI 48202, USA
| | - Chao Li
- Department of Neurology, Henry Ford Health System, Detroit, MI 48202, USA
| | - Yi Zhang
- Department of Neurology, Henry Ford Health System, Detroit, MI 48202, USA
| | - Yisheng Cui
- Department of Neurology, Henry Ford Health System, Detroit, MI 48202, USA
| | - Cynthia Roberts
- Department of Neurology, Henry Ford Health System, Detroit, MI 48202, USA
| | - Neema Sadry
- Department of Neurology, Henry Ford Health System, Detroit, MI 48202, USA
| | - Xianshuang Liu
- Department of Neurology, Henry Ford Health System, Detroit, MI 48202, USA
| | - Michael Chopp
- Department of Neurology, Henry Ford Health System, Detroit, MI 48202, USA; Department of Physics, Oakland University, Rochester, MI 48309, USA
| | - Zheng Gang Zhang
- Department of Neurology, Henry Ford Health System, Detroit, MI 48202, USA.
| |
Collapse
|
75
|
Woolsey TA. Re: Woolsey TA, van der Loos H. 1970. The structural organization of layer IV in the somatosensory region (S I) of mouse cerebral cortex. Brain Res. 17: 205-242. Brain Res 2016; 1645:22-4. [PMID: 27086973 DOI: 10.1016/j.brainres.2016.04.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 04/13/2016] [Indexed: 10/22/2022]
Abstract
UNLABELLED Axoplasmically transported proteins synthesized in neuronal somata labeled by radioactively labeled amino acids (tritium), following local targeted injections for tracing of pathways in the central nervous system using autoradiography. Results from a number of neuronal systems, including: the rat olfactory bulb; cortico-thalamic projections in the mouse; commissural connections of the rat hippocampus; and retinal projections in the monkey and chick are documented. Pathway origins are clear, as the number and distribution of the labeled cells and the normal structure of the injection site is preserved. Light and electron microscopic autoradiography shows that proteins are transported, at two rates: rapid transport (>100mm/day) of fewer proteins accumulating in axon terminals; and, slow transport (1-5mm/day) of the bulk of labeled proteins distributed along the length of axons. Different survival times can be selected to evaluate terminal projection field(s) or pathways from origin to termination. The clarity of autoradiographic labeling of pathways and their terminations is comparable to other techniques (such as the Nauta-Gygax and the Fink-Heimer methods and the electron microscopy of terminal degeneration). Labeled amino acids do not label molecules in fibers of passage and there is no retrograde transport of labeled material from the axon terminals. The functional polarity of fiber pathways can be easily established. We summarize the merits of this technique is based upon an established physiological properties of neurons that are summarized in contrast to currently used techniques dependent upon pathological changes in neurons, axons, or axonal terminals. ABSTRACT The cytoarchitecture of layer IV in mouse SmI cerebral cortex was examined in.formalin-fixed, Nissl-stained and Cox-fixed, Golgi-Nissl-stained sections cut coronally and tangentially to the pia, A multicellular cytoarchitectonic unit is described in layer IV, roughly cylindrical, 100-400um in diameter, and perpendicular to the pia. Because of their characteristic shape we call these structures barrels. Each barrel is a ring of neurons, the side, which surrounds a less cellular hollow. The nearly acellular reigion surrounding each barrel and separating adjacent barrels is the septum. Barrels are discussed in relation to observations reported in several earlier papers on the mouse cortex. The barrel field (all barrels) has remarkable constancy by all measures: from one hemisphere to the next and from one specimen to the next. A consistent part of the barrel field is the postero-medial barrel subield (PMBSF). Barrels in the PMBSF are larger, elliptical in shape, organized into five distinct rows and their numbers are constant. It is postulated that each barrel in the PMBSF is the cortical correlate of a contralateral mystacial vibrissa (whisker). On the basis of counts of barrels and of all facial sinus hairs a 'one barrel-one vibrissa' hypothesis is proposed. The general hypothesis is that barrels are the morphological manifestation in layer IV of the functional cortical columns discovered by physiologists. The barrels offer excellent opportunities for integrated studies of sensory cerebral cortex at a degree of resolution previously not possible. This article is part of a Special Issue entitled SI:50th Anniversary Issue.
Collapse
Affiliation(s)
- Thomas A Woolsey
- Biology, Neurosurgery, Neurology, Anatomy and Neurobiology, Biomedical Engineering , Washington University in St. Louis, United States.
| |
Collapse
|
76
|
Abstract
Stroke not only causes initial cell death, but also a limited process of repair and recovery. As an overall biological process, stroke has been most often considered from the perspective of early phases of ischemia, how these inter-relate and lead to expansion of the infarct. However, just as the biology of later stages of stroke becomes better understood, the clinical realities of stroke indicate that it is now more a chronic disease than an acute killer. As an overall biological process, it is now more important to understand how early cell death leads to the later, limited recovery so as develop an integrative view of acute to chronic stroke. This progression from death to repair involves sequential stages of primary cell death, secondary injury events, reactive tissue progenitor responses, and formation of new neuronal circuits. This progression is radial: from the tissue that suffers the infarct secondary injury signals, including free radicals and inflammatory cytokines, radiate out from the stroke core to trigger later regenerative events. Injury and repair processes occur not just in the local stroke site, but are also triggered in the connected networks of neurons that had existed in the stroke center: damage signals are relayed throughout a brain network. From these relayed, distributed damage signals, reactive astrocytosis, inflammatory processes, and the formation of new connections occur in distant brain areas. In short, emerging data in stroke cell death studies and the development of the field of stroke neural repair now indicate a continuum in time and in space of progressive events that can be considered as the 3 Rs of stroke biology: radial, relayed, and regenerative.
Collapse
Affiliation(s)
- S Thomas Carmichael
- Departments of Neurology and Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
| |
Collapse
|
77
|
Berretta A, Gowing EK, Jasoni CL, Clarkson AN. Sonic hedgehog stimulates neurite outgrowth in a mechanical stretch model of reactive-astrogliosis. Sci Rep 2016; 6:21896. [PMID: 26902390 PMCID: PMC4763245 DOI: 10.1038/srep21896] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 02/01/2016] [Indexed: 01/15/2023] Open
Abstract
Although recovery following a stroke is limited, undamaged neurons under the right conditions can establish new connections and take on-board lost functions. Sonic hedgehog (Shh) signaling is integral for developmental axon growth, but its role after injury has not been fully examined. To investigate the effects of Shh on neuronal sprouting after injury, we used an in vitro model of glial scar, whereby cortical astrocytes were mechanically traumatized to mimic reactive astrogliosis observed after stroke. This mechanical trauma impaired neurite outgrowth from post-natal cortical neurons plated on top of reactive astrocytes. Addition of Shh to the media, however, resulted in a concentration-dependent increase in neurite outgrowth. This response was inhibited by cyclopamine and activated by oxysterol 20(S)-hydroxycholesterol, both of which modulate the activity of the Shh co-receptor Smoothened (Smo), demonstrating that Shh-mediated neurite outgrowth is Smo-dependent. In addition, neurite outgrowth was not associated with an increase in Gli-1 transcription, but could be inhibited by PP2, a selective inhibitor of Src family kinases. These results demonstrate that neurons exposed to the neurite growth inhibitory environment associated with a glial scar can be stimulated by Shh, with signaling occurring through a non-canonical pathway, to overcome this suppression and stimulate neurite outgrowth.
Collapse
Affiliation(s)
- Antonio Berretta
- Department of Anatomy, Brain Health Research Centre, University of Otago, Dunedin 9054, New Zealand.
| | - Emma K. Gowing
- Department of Anatomy, Brain Health Research Centre, University of Otago, Dunedin 9054, New Zealand.
| | - Christine L. Jasoni
- Department of Anatomy, Brain Health Research Centre, University of Otago, Dunedin 9054, New Zealand.
| | - Andrew N. Clarkson
- Department of Anatomy, Brain Health Research Centre, University of Otago, Dunedin 9054, New Zealand.
- Brain Research New Zealand, University of Otago, PO Box 913, Dunedin 9054, New Zealand
- Faculty of Pharmacy, The University of Sydney, Sydney, Australia
| |
Collapse
|
78
|
Xu Y, Hou QH, Russell SD, Bennett BC, Sellers AJ, Lin Q, Huang DF. Neuroplasticity in post-stroke gait recovery and noninvasive brain stimulation. Neural Regen Res 2016; 10:2072-80. [PMID: 26889202 PMCID: PMC4730838 DOI: 10.4103/1673-5374.172329] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Gait disorders drastically affect the quality of life of stroke survivors, making post-stroke rehabilitation an important research focus. Noninvasive brain stimulation has potential in facilitating neuroplasticity and improving post-stroke gait impairment. However, a large inter-individual variability in the response to noninvasive brain stimulation interventions has been increasingly recognized. We first review the neurophysiology of human gait and post-stroke neuroplasticity for gait recovery, and then discuss how noninvasive brain stimulation techniques could be utilized to enhance gait recovery. While post-stroke neuroplasticity for gait recovery is characterized by use-dependent plasticity, it evolves over time, is idiosyncratic, and may develop maladaptive elements. Furthermore, noninvasive brain stimulation has limited reach capability and is facilitative-only in nature. Therefore, we recommend that noninvasive brain stimulation be used adjunctively with rehabilitation training and other concurrent neuroplasticity facilitation techniques. Additionally, when noninvasive brain stimulation is applied for the rehabilitation of gait impairment in stroke survivors, stimulation montages should be customized according to the specific types of neuroplasticity found in each individual. This could be done using multiple mapping techniques.
Collapse
Affiliation(s)
- Yi Xu
- Department of Rehabilitation Medicine, the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China; Guangdong Provincial Engineering Technology Research Center for Rehabilitation Medicine and Clinical Translation, Guangzhou, Guangdong Province, China; Motion Analysis and Motor Performance Laboratory, Department of Orthopedics and Mechanical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Qing-Hua Hou
- Department of Neurology, Guangdong No.2 Provincial People's Hospital, Guangzhou, Guangdong Province, China
| | - Shawn D Russell
- Motion Analysis and Motor Performance Laboratory, Department of Orthopedics and Mechanical Engineering, University of Virginia, Charlottesville, VA, USA
| | - Bradford C Bennett
- H.C Sweere Center for Clinical Biomechanics and Applied Ergonomics, Northwestern Health Science University, Bloomington, MN, USA
| | - Andrew J Sellers
- Department of Radiology, Naval Medical Center Portsmouth, Portsmouth, VA, USA
| | - Qiang Lin
- Department of Rehabilitation Medicine, the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China; Guangdong Provincial Engineering Technology Research Center for Rehabilitation Medicine and Clinical Translation, Guangzhou, Guangdong Province, China
| | - Dong-Feng Huang
- Department of Rehabilitation Medicine, the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China; Guangdong Provincial Engineering Technology Research Center for Rehabilitation Medicine and Clinical Translation, Guangzhou, Guangdong Province, China
| |
Collapse
|
79
|
Carmichael ST, Kathirvelu B, Schweppe CA, Nie EH. Molecular, cellular and functional events in axonal sprouting after stroke. Exp Neurol 2016; 287:384-394. [PMID: 26874223 DOI: 10.1016/j.expneurol.2016.02.007] [Citation(s) in RCA: 124] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2015] [Revised: 02/06/2016] [Accepted: 02/09/2016] [Indexed: 01/26/2023]
Abstract
Stroke is the leading cause of adult disability. Yet there is a limited degree of recovery in this disease. One of the mechanisms of recovery is the formation of new connections in the brain and spinal cord after stroke: post-stroke axonal sprouting. Studies indicate that post-stroke axonal sprouting occurs in mice, rats, primates and humans. Inducing post-stroke axonal sprouting in specific connections enhances recovery; blocking axonal sprouting impairs recovery. Behavioral activity patterns after stroke modify the axonal sprouting response. A unique regenerative molecular program mediates this aspect of tissue repair in the CNS. The types of connections that are formed after stroke indicate three patterns of axonal sprouting after stroke: reactive, reparative and unbounded axonal sprouting. These differ in mechanism, location, relationship to behavioral recovery and, importantly, in their prospect for therapeutic manipulation to enhance tissue repair.
Collapse
Affiliation(s)
- S Thomas Carmichael
- Departments of Neurology and of Neurobiology, David Geffen School of Medicine at UCLA, 710 Westwood Plaza, Los Angeles, CA 90095, USA.
| | - Balachandar Kathirvelu
- Departments of Neurology and of Neurobiology, David Geffen School of Medicine at UCLA, 710 Westwood Plaza, Los Angeles, CA 90095, USA.
| | - Catherine A Schweppe
- Departments of Neurology and of Neurobiology, David Geffen School of Medicine at UCLA, 710 Westwood Plaza, Los Angeles, CA 90095, USA.
| | - Esther H Nie
- Departments of Neurology and of Neurobiology, David Geffen School of Medicine at UCLA, 710 Westwood Plaza, Los Angeles, CA 90095, USA.
| |
Collapse
|
80
|
Rabiller G, He JW, Nishijima Y, Wong A, Liu J. Perturbation of Brain Oscillations after Ischemic Stroke: A Potential Biomarker for Post-Stroke Function and Therapy. Int J Mol Sci 2015; 16:25605-40. [PMID: 26516838 PMCID: PMC4632818 DOI: 10.3390/ijms161025605] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 10/06/2015] [Accepted: 10/15/2015] [Indexed: 01/08/2023] Open
Abstract
Brain waves resonate from the generators of electrical current and propagate across brain regions with oscillation frequencies ranging from 0.05 to 500 Hz. The commonly observed oscillatory waves recorded by an electroencephalogram (EEG) in normal adult humans can be grouped into five main categories according to the frequency and amplitude, namely δ (1-4 Hz, 20-200 μV), θ (4-8 Hz, 10 μV), α (8-12 Hz, 20-200 μV), β (12-30 Hz, 5-10 μV), and γ (30-80 Hz, low amplitude). Emerging evidence from experimental and human studies suggests that groups of function and behavior seem to be specifically associated with the presence of each oscillation band, although the complex relationship between oscillation frequency and function, as well as the interaction between brain oscillations, are far from clear. Changes of brain oscillation patterns have long been implicated in the diseases of the central nervous system including ischemic stroke, in which the reduction of cerebral blood flow as well as the progression of tissue damage have direct spatiotemporal effects on the power of several oscillatory bands and their interactions. This review summarizes the current knowledge in behavior and function associated with each brain oscillation, and also in the specific changes in brain electrical activities that correspond to the molecular events and functional alterations observed after experimental and human stroke. We provide the basis of the generations of brain oscillations and potential cellular and molecular mechanisms underlying stroke-induced perturbation. We will also discuss the implications of using brain oscillation patterns as biomarkers for the prediction of stroke outcome and therapeutic efficacy.
Collapse
Affiliation(s)
- Gratianne Rabiller
- Department of Neurological Surgery, University of California at San Francisco and Department of Veterans Affairs Medical Center, 1700 Owens Street, San Francisco, CA 94158, USA.
- UCSF and SFVAMC, San Francisco, CA 94158, USA.
- Univ. de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux 33000, France.
- CNRS, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux 33000, France.
| | - Ji-Wei He
- Department of Neurological Surgery, University of California at San Francisco and Department of Veterans Affairs Medical Center, 1700 Owens Street, San Francisco, CA 94158, USA.
- UCSF and SFVAMC, San Francisco, CA 94158, USA.
| | - Yasuo Nishijima
- Department of Neurological Surgery, University of California at San Francisco and Department of Veterans Affairs Medical Center, 1700 Owens Street, San Francisco, CA 94158, USA.
- UCSF and SFVAMC, San Francisco, CA 94158, USA.
- Department of Neurosurgery, Tohoku University Graduate School of Medicine 1-1 Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan.
| | - Aaron Wong
- Department of Neurological Surgery, University of California at San Francisco and Department of Veterans Affairs Medical Center, 1700 Owens Street, San Francisco, CA 94158, USA.
- UCSF and SFVAMC, San Francisco, CA 94158, USA.
- Rice University, 6100 Main St, Houston, TX 77005, USA.
| | - Jialing Liu
- Department of Neurological Surgery, University of California at San Francisco and Department of Veterans Affairs Medical Center, 1700 Owens Street, San Francisco, CA 94158, USA.
- UCSF and SFVAMC, San Francisco, CA 94158, USA.
| |
Collapse
|
81
|
Caleo M. Rehabilitation and plasticity following stroke: Insights from rodent models. Neuroscience 2015; 311:180-94. [PMID: 26493858 DOI: 10.1016/j.neuroscience.2015.10.029] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 10/11/2015] [Accepted: 10/12/2015] [Indexed: 01/08/2023]
Abstract
Ischemic injuries within the motor cortex result in functional deficits that may profoundly impact activities of daily living in patients. Current rehabilitation protocols achieve only limited recovery of motor abilities. The brain reorganizes spontaneously after injury, and it is believed that appropriately boosting these neuroplastic processes may restore function via recruitment of spared areas and pathways. Here I review studies on circuit reorganization, neuronal and glial plasticity and axonal sprouting following ischemic damage to the forelimb motor cortex, with a particular focus on rodent models. I discuss evidence pointing to compensatory take-over of lost functions by adjacent peri-lesional areas and the role of the contralesional hemisphere in recovery. One key issue is the need to distinguish "true" recovery (i.e. re-establishment of original movement patterns) from compensation in the assessment of post-stroke functional gains. I also consider the effects of physical rehabilitation, including robot-assisted therapy, and the potential mechanisms by which motor training induces recovery. Finally, I describe experimental approaches in which training is coupled with delivery of plasticizing drugs that render the remaining, undamaged pathways more sensitive to experience-dependent modifications. These combinatorial strategies hold promise for the definition of more effective rehabilitation paradigms that can be translated into clinical practice.
Collapse
Affiliation(s)
- M Caleo
- CNR Neuroscience Institute, via G. Moruzzi 1, 56124 Pisa, Italy; The BioRobotics Institute, Scuola Superiore Sant'Anna, P.zza Martiri della Libertà 33, 56127 Pisa, Italy.
| |
Collapse
|
82
|
Buetefisch CM. Role of the Contralesional Hemisphere in Post-Stroke Recovery of Upper Extremity Motor Function. Front Neurol 2015; 6:214. [PMID: 26528236 PMCID: PMC4607877 DOI: 10.3389/fneur.2015.00214] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Accepted: 09/22/2015] [Indexed: 12/14/2022] Open
Abstract
Identification of optimal treatment strategies to improve recovery is limited by the incomplete understanding of the neurobiological principles of recovery. Motor cortex (M1) reorganization of the lesioned hemisphere (ipsilesional M1) plays a major role in post-stroke motor recovery and is a primary target for rehabilitation therapy. Reorganization of M1 in the hemisphere contralateral to the stroke (contralesional M1) may, however, serve as an additional source of cortical reorganization and related recovery. The extent and outcome of such reorganization depends on many factors, including lesion size and time since stroke. In the chronic phase post-stroke, contralesional M1 seems to interfere with motor function of the paretic limb in a subset of patients, possibly through abnormally increased inhibition of lesioned M1 by the contralesional M1. In such patients, decreasing contralesional M1 excitability by cortical stimulation results in improved performance of the paretic limb. However, emerging evidence suggests a potentially supportive role of contralesional M1. After infarction of M1 or its corticospinal projections, there is abnormally increased excitatory neural activity and activation in contralesional M1 that correlates with favorable motor recovery. Decreasing contralesional M1 excitability in these patients may result in deterioration of paretic limb performance. In animal stroke models, reorganizational changes in contralesional M1 depend on the lesion size and rehabilitation treatment and include long-term changes in neurotransmitter systems, dendritic growth, and synapse formation. While there is, therefore, some evidence that activity in contralesional M1 will impact the extent of motor function of the paretic limb in the subacute and chronic phase post-stroke and may serve as a new target for rehabilitation treatment strategies, the precise factors that specifically influence its role in the recovery process remain to be defined.
Collapse
Affiliation(s)
- Cathrin M Buetefisch
- Emory University , Atlanta, GA , USA ; Georgia Institute of Technology , Atlanta, GA , USA
| |
Collapse
|
83
|
Jones TA, Adkins DL. Motor System Reorganization After Stroke: Stimulating and Training Toward Perfection. Physiology (Bethesda) 2015; 30:358-70. [PMID: 26328881 PMCID: PMC4556825 DOI: 10.1152/physiol.00014.2015] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Stroke instigates regenerative responses that reorganize connectivity patterns among surviving neurons. The new connectivity patterns can be suboptimal for behavioral function. This review summarizes current knowledge on post-stroke motor system reorganization and emerging strategies for shaping it with manipulations of behavior and cortical activity to improve functional outcome.
Collapse
Affiliation(s)
- Theresa A Jones
- Psychology Department, Neuroscience Institute, University of Texas at Austin, Austin, Texas; and
| | - DeAnna L Adkins
- Neurosciences Department, and Health Sciences & Research Department, Colleges of Medicine & Health Professions, Medical University of South Carolina, Charleston, South Carolina
| |
Collapse
|
84
|
Alawieh A, Elvington A, Tomlinson S. Complement in the Homeostatic and Ischemic Brain. Front Immunol 2015; 6:417. [PMID: 26322048 PMCID: PMC4533015 DOI: 10.3389/fimmu.2015.00417] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 07/30/2015] [Indexed: 11/29/2022] Open
Abstract
The complement system is a component of the immune system involved in both recognition and response to pathogens, and it is implicated in an increasing number of homeostatic and disease processes. It is well documented that reperfusion of ischemic tissue results in complement activation and an inflammatory response that causes post-reperfusion injury. This occurs following cerebral ischemia and reperfusion and triggers secondary damage that extends beyond the initial infarcted area, an outcome that has rationalized the use of complement inhibitors as candidate therapeutics after stroke. In the central nervous system, however, recent studies have revealed that complement also has essential roles in synaptic pruning, neurogenesis, and neuronal migration. In the context of recovery after stroke, these apparent divergent functions of complement may account for findings that the protective effect of complement inhibition in the acute phase after stroke is not always maintained in the subacute and chronic phases. The development of effective stroke therapies based on modulation of the complement system will require a detailed understanding of complement-dependent processes in both early neurodegenerative events and delayed neuro-reparatory processes. Here, we review the role of complement in normal brain physiology, the events initiating complement activation after cerebral ischemia-reperfusion injury, and the contribution of complement to both injury and recovery. We also discuss how the design of future experiments may better characterize the dual role of complement in recovery after ischemic stroke.
Collapse
Affiliation(s)
- Ali Alawieh
- Neuroscience Institute, Department of Neurosciences, Medical University of South Carolina , Charleston, SC , USA
| | - Andrew Elvington
- Department of Pathology and Immunology, Washington University School of Medicine , St. Louis, MO , USA
| | - Stephen Tomlinson
- Department of Microbiology and Immunology, Ralph H. Johnson Veteran Affairs Medical Center, Medical University of South Carolina , Charleston, SC , USA
| |
Collapse
|
85
|
Wessel MJ, Zimerman M, Hummel FC. Non-invasive brain stimulation: an interventional tool for enhancing behavioral training after stroke. Front Hum Neurosci 2015; 9:265. [PMID: 26029083 PMCID: PMC4432668 DOI: 10.3389/fnhum.2015.00265] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2015] [Accepted: 04/23/2015] [Indexed: 01/20/2023] Open
Abstract
Stroke is the leading cause of disability among adults. Motor deficit is the most common impairment after stroke. Especially, deficits in fine motor skills impair numerous activities of daily life. Re-acquisition of motor skills resulting in improved or more accurate motor performance is paramount to regain function, and is the basis of behavioral motor therapy after stroke. Within the past years, there has been a rapid technological and methodological development in neuroimaging leading to a significant progress in the understanding of the neural substrates that underlie motor skill acquisition and functional recovery in stroke patients. Based on this and the development of novel non-invasive brain stimulation (NIBS) techniques, new adjuvant interventional approaches that augment the response to behavioral training have been proposed. Transcranial direct current, transcranial magnetic, and paired associative (PAS) stimulation are NIBS techniques that can modulate cortical excitability, neuronal plasticity and interact with learning and memory in both healthy individuals and stroke patients. These techniques can enhance the effect of practice and facilitate the retention of tasks that mimic daily life activities. The purpose of the present review is to provide a comprehensive overview of neuroplastic phenomena in the motor system during learning of a motor skill, recovery after brain injury, and of interventional strategies to enhance the beneficial effects of customarily used neurorehabilitation after stroke.
Collapse
Affiliation(s)
- Maximilian J Wessel
- Brain Imaging and Neurostimulation (BINS) Laboratory, Department of Neurology, University Medical Center Hamburg-Eppendorf , Hamburg , Germany
| | - Máximo Zimerman
- Brain Imaging and Neurostimulation (BINS) Laboratory, Department of Neurology, University Medical Center Hamburg-Eppendorf , Hamburg , Germany ; Institute of Cognitive Neurology (INECO) , Buenos Aires , Argentina
| | - Friedhelm C Hummel
- Brain Imaging and Neurostimulation (BINS) Laboratory, Department of Neurology, University Medical Center Hamburg-Eppendorf , Hamburg , Germany ; Favaloro University , Buenos Aires , Argentina
| |
Collapse
|
86
|
Kassis H, Shehadah A, Chopp M, Roberts C, Zhang ZG. Stroke Induces Nuclear Shuttling of Histone Deacetylase 4. Stroke 2015; 46:1909-15. [PMID: 25967576 DOI: 10.1161/strokeaha.115.009046] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 04/15/2015] [Indexed: 01/14/2023]
Abstract
BACKGROUND AND PURPOSE Histone deacetylases (HDACs) 4 and 5 are abundantly expressed in the brain and have been implicated in the regulation of neurodegeneration. Under physiological conditions, HDACs 4 and 5 are expressed in the cytoplasm of brain cells where they cannot directly access chromatin. In response to external stimuli, they can shuttle to the nucleus and regulate gene expression. However, the effect of stroke on nuclear shuttling of HDACs 4 and 5 remains unknown. METHODS Using a rat model of middle cerebral artery occlusion, we examined the subcellular localization of HDACs 4 and 5 in the peri-infarct cortex during brain repair after stroke. RESULTS Stroke significantly increased nuclear HDAC4 immunoreactivity in neurons, but not in astrocytes or in oligodendrocytes, of the peri-infarct cortex at 2, 7, and 14 days after middle cerebral artery occlusion. Neurons with nuclear HDAC4 immunoreactivity distributed across all layers of the peri-infarct cortex and were Ctip2+ excitatory and parvalbumin+ inhibitory neurons. These neurons were not TUNEL or BrdU positive. Furthermore, nuclear HDAC4 immunoreactivity was positively and significantly correlated with increased dendritic, axonal, and myelin densities as determined by microtubule-associated protein 2, phosphorylated neurofilament heavy chain, and myelin basic protein, respectively. Unlike HDAC4, stroke did not alter nuclear localization of HDAC5. CONCLUSIONS Our data show that stroke induces nuclear shuttling of HDAC4 in neurons in the peri-infarct cortex, and that increased nuclear HDAC4 is strongly associated with neuronal remodeling but not with neuronal cell death, suggesting a role for nuclear HDAC4 in promoting neuronal recovery after ischemic injury.
Collapse
Affiliation(s)
- Haifa Kassis
- From the Department of Neurology, Henry Ford Health System, Detroit, MI (H.K., A.S., M.C., C.R., Z.G.Z.); and Department of Physics, Oakland University, Rochester, MI (M.C.)
| | - Amjad Shehadah
- From the Department of Neurology, Henry Ford Health System, Detroit, MI (H.K., A.S., M.C., C.R., Z.G.Z.); and Department of Physics, Oakland University, Rochester, MI (M.C.)
| | - Michael Chopp
- From the Department of Neurology, Henry Ford Health System, Detroit, MI (H.K., A.S., M.C., C.R., Z.G.Z.); and Department of Physics, Oakland University, Rochester, MI (M.C.)
| | - Cynthia Roberts
- From the Department of Neurology, Henry Ford Health System, Detroit, MI (H.K., A.S., M.C., C.R., Z.G.Z.); and Department of Physics, Oakland University, Rochester, MI (M.C.)
| | - Zheng Gang Zhang
- From the Department of Neurology, Henry Ford Health System, Detroit, MI (H.K., A.S., M.C., C.R., Z.G.Z.); and Department of Physics, Oakland University, Rochester, MI (M.C.).
| |
Collapse
|
87
|
Horie N, Hiu T, Nagata I. Stem cell transplantation enhances endogenous brain repair after experimental stroke. Neurol Med Chir (Tokyo) 2015; 55:107-12. [PMID: 25746304 PMCID: PMC4533406 DOI: 10.2176/nmc.ra.2014-0271] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Stem cell transplantation for stroke treatment has been a promising therapy in small and large animal models, and many clinical trials are ongoing to establish this strategy in a clinical setting. However, the mechanism underlying functional recovery after stem cell transplantation has not been fully established and there is still a need to determine the ideal subset of stem cells for such therapy. We herein reviewed the recent evidences showing the underlying mechanism of functional recovery after cell transplantation, focusing on endogenous brain repair. First, angiogenesis/neovascularization is promoted by trophic factors including vascular endothelial growth factor secreted from stem cells, and stem cells migrated to the lesion along with the vessels. Second, axonal sprouting, dendritic branching, and synaptogenesis were enhanced altogether in the both ipsilateral and contralateral hemisphere remapping the pyramidal tract across the board. Finally, endogenous neurogenesis was also enhanced although little is known how much these neurogenesis contribute to the functional recovery. Taken together, it is clear that stem cell transplantation provides functional recovery via endogenous repair enhancement from multiple ways. This is important to maximize the effect of stem cell therapy after stroke, although it is still undetermined which repair mechanism is mostly contributed.
Collapse
Affiliation(s)
- Nobutaka Horie
- Department of Neurosurgery, Nagasaki University School of Medicine
| | | | | |
Collapse
|
88
|
Silasi G, Murphy TH. Stroke and the connectome: how connectivity guides therapeutic intervention. Neuron 2015; 83:1354-68. [PMID: 25233317 DOI: 10.1016/j.neuron.2014.08.052] [Citation(s) in RCA: 140] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/25/2014] [Indexed: 11/30/2022]
Abstract
Connections between neurons are affected within 3 min of stroke onset by massive ischemic depolarization and then delayed cell death. Some connections can recover with prompt reperfusion; others associated with the dying infarct do not. Disruption in functional connectivity is due to direct tissue loss and indirect disconnections of remote areas known as diaschisis. Stroke is devastating, yet given the brain's redundant design, collateral surviving networks and their connections are well-positioned to compensate. Our perspective is that new treatments for stroke may involve a rational functional and structural connections-based approach. Surviving, affected, and at-risk networks can be identified and targeted with scenario-specific treatments. Strategies for recovery may include functional inhibition of the intact hemisphere, rerouting of connections, or setpoint-mediated network plasticity. These approaches may be guided by brain imaging and enabled by patient- and injury-specific brain stimulation, rehabilitation, and potential molecule-based strategies to enable new connections.
Collapse
Affiliation(s)
- Gergely Silasi
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, BC V6T 1Z3, Canada; Brain Research Centre, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Timothy H Murphy
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, BC V6T 1Z3, Canada; Brain Research Centre, University of British Columbia, Vancouver, BC V6T 1Z3, Canada.
| |
Collapse
|
89
|
Corbett D, Jeffers M, Nguemeni C, Gomez-Smith M, Livingston-Thomas J. Lost in translation: rethinking approaches to stroke recovery. PROGRESS IN BRAIN RESEARCH 2015; 218:413-34. [PMID: 25890148 DOI: 10.1016/bs.pbr.2014.12.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Stroke is the second leading cause of death and the preeminent cause of neurological disability. Attempts to limit brain injury after ischemic stroke with clot-dissolving drugs have met with great success but their use remains limited due to a narrow therapeutic time window and concern over serious side effects. Unfortunately, the neuroprotective strategy failed in clinical trials. A more promising approach is to promote recovery of function in people affected by stroke. Following stroke, there is a heightened critical period of plasticity that appears to be receptive to exogenous interventions (e.g., delivery of growth factors) designed to enhance neuroplasticity processes important for recovery. An emerging concept is that combinational therapies appear much more effective than single interventions in improving stroke recovery. One of the most promising interventions, with clinical feasibility, is enriched rehabilitation, a combination of environmental enrichment and task-specific therapy.
Collapse
Affiliation(s)
- Dale Corbett
- Heart & Stroke Foundation Canadian Partnership for Stroke Recovery and Department of Cellular & Molecular Medicine, University of Ottawa, Ottawa, Canada.
| | - Matthew Jeffers
- Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada; Canadian Partnership for Stroke Recovery, University of Ottawa, Ottawa, Ontario, Canada
| | - Carine Nguemeni
- Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada; Canadian Partnership for Stroke Recovery, University of Ottawa, Ottawa, Ontario, Canada
| | - Mariana Gomez-Smith
- Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada; Canadian Partnership for Stroke Recovery, University of Ottawa, Ottawa, Ontario, Canada
| | - Jessica Livingston-Thomas
- Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada; Canadian Partnership for Stroke Recovery, University of Ottawa, Ottawa, Ontario, Canada
| |
Collapse
|
90
|
Balsara RD, Chapman SE, Sander IM, Donahue DL, Liepert L, Castellino FJ, Leevy WM. Non-invasive imaging and analysis of cerebral ischemia in living rats using positron emission tomography with 18F-FDG. J Vis Exp 2014:51495. [PMID: 25590998 PMCID: PMC4354491 DOI: 10.3791/51495] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Stroke is the third leading cause of death among Americans 65 years of age or older(1). The quality of life for patients who suffer from a stroke fails to return to normal in a large majority of patients(2), which is mainly due to current lack of clinical treatment for acute stroke. This necessitates understanding the physiological effects of cerebral ischemia on brain tissue over time and is a major area of active research. Towards this end, experimental progress has been made using rats as a preclinical model for stroke, particularly, using non-invasive methods such as (18)F-fluorodeoxyglucose (FDG) coupled with Positron Emission Tomography (PET) imaging(3,10,17). Here we present a strategy for inducing cerebral ischemia in rats by middle cerebral artery occlusion (MCAO) that mimics focal cerebral ischemia in humans, and imaging its effects over 24 hr using FDG-PET coupled with X-ray computed tomography (CT) with an Albira PET-CT instrument. A VOI template atlas was subsequently fused to the cerebral rat data to enable a unbiased analysis of the brain and its sub-regions(4). In addition, a method for 3D visualization of the FDG-PET-CT time course is presented. In summary, we present a detailed protocol for initiating, quantifying, and visualizing an induced ischemic stroke event in a living Sprague-Dawley rat in three dimensions using FDG-PET.
Collapse
Affiliation(s)
- Rashna D Balsara
- W. M. Keck Center for Transgene Research, University of Notre Dame; Department of Chemistry and Biochemistry, University of Notre Dame
| | - Sarah E Chapman
- Notre Dame Integrated Imaging Facility, University of Notre Dame
| | - Ian M Sander
- Department of Biological Sciences, University of Notre Dame
| | | | - Lucas Liepert
- Department of Biological Sciences, University of Notre Dame
| | - Francis J Castellino
- W. M. Keck Center for Transgene Research, University of Notre Dame; Department of Chemistry and Biochemistry, University of Notre Dame
| | - W Matthew Leevy
- Notre Dame Integrated Imaging Facility, University of Notre Dame; Department of Biological Sciences, University of Notre Dame; Harper Cancer Research Institute, University of Notre Dame;
| |
Collapse
|
91
|
Lin YC, Daducci A, Meskaldji DE, Thiran JP, Michel P, Meuli R, Krueger G, Menegaz G, Granziera C. Quantitative Analysis of Myelin and Axonal Remodeling in the Uninjured Motor Network After Stroke. Brain Connect 2014; 5:401-12. [PMID: 25296185 DOI: 10.1089/brain.2014.0245] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Contralesional brain connectivity plasticity was previously reported after stroke. This study aims at disentangling the biological mechanisms underlying connectivity plasticity in the uninjured motor network after an ischemic lesion. In particular, we measured generalized fractional anisotropy (GFA) and magnetization transfer ratio (MTR) to assess whether poststroke connectivity remodeling depends on axonal and/or myelin changes. Diffusion-spectrum imaging and magnetization transfer MRI at 3T were performed in 10 patients in acute phase, at 1 and 6 months after stroke, which was affecting motor cortical and/or subcortical areas. Ten age- and gender-matched healthy volunteers were scanned 1 month apart for longitudinal comparison. Clinical assessment was also performed in patients prior to magnetic resonance imaging (MRI). In the contralesional hemisphere, average measures and tract-based quantitative analysis of GFA and MTR were performed to assess axonal integrity and myelination along motor connections as well as their variations in time. Mean and tract-based measures of MTR and GFA showed significant changes in a number of contralesional motor connections, confirming both axonal and myelin plasticity in our cohort of patients. Moreover, density-derived features (peak height, standard deviation, and skewness) of GFA and MTR along the tracts showed additional correlation with clinical scores than mean values. These findings reveal the interplay between contralateral myelin and axonal remodeling after stroke.
Collapse
Affiliation(s)
- Ying-Chia Lin
- 1 Department of Computer Science, University of Verona , Verona, Italy
| | - Alessandro Daducci
- 2 STI/IEL/LTS5 , Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Djalel Eddine Meskaldji
- 3 Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland .,4 Department of Radiology and Medical Informatics, University of Geneva , Geneva, Switzerland
| | - Jean-Philippe Thiran
- 2 STI/IEL/LTS5 , Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Patrik Michel
- 5 Stroke Center, Department of Clinical Neurosciences, Centre Hospitalier Universitaire Vaudois, University of Lausanne , Lausanne, Switzerland
| | - Reto Meuli
- 6 Department of Radiology, Centre Hospitalier Universitaire Vaudois, University of Lausanne , Lausanne, Switzerland
| | - Gunnar Krueger
- 7 Healthcare Sector IM&WS S, Siemens Schweiz AG, Lausanne, Switzerland .,8 Advanced Clinical Imaging Technology Group, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Gloria Menegaz
- 1 Department of Computer Science, University of Verona , Verona, Italy
| | - Cristina Granziera
- 2 STI/IEL/LTS5 , Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland .,8 Advanced Clinical Imaging Technology Group, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland .,9 Laboratoire de Recherche en Neuroimagerie and Neuroimmunology Unit, Department of Clinical Neurosciences, Centre Hospitalier Universitaire Vaudois and University of Lausanne , Lausanne, Switzerland
| |
Collapse
|
92
|
Interplay between intra- and interhemispheric remodeling of neural networks as a substrate of functional recovery after stroke: Adaptive versus maladaptive reorganization. Neuroscience 2014; 283:178-201. [DOI: 10.1016/j.neuroscience.2014.06.066] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Revised: 06/27/2014] [Accepted: 06/27/2014] [Indexed: 11/18/2022]
|
93
|
Butz M, Steenbuck ID, van Ooyen A. Homeostatic structural plasticity can account for topology changes following deafferentation and focal stroke. Front Neuroanat 2014; 8:115. [PMID: 25360087 PMCID: PMC4199279 DOI: 10.3389/fnana.2014.00115] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 09/24/2014] [Indexed: 01/12/2023] Open
Abstract
After brain lesions caused by tumors or stroke, or after lasting loss of input (deafferentation), inter- and intra-regional brain networks respond with complex changes in topology. Not only areas directly affected by the lesion but also regions remote from the lesion may alter their connectivity—a phenomenon known as diaschisis. Changes in network topology after brain lesions can lead to cognitive decline and increasing functional disability. However, the principles governing changes in network topology are poorly understood. Here, we investigated whether homeostatic structural plasticity can account for changes in network topology after deafferentation and brain lesions. Homeostatic structural plasticity postulates that neurons aim to maintain a desired level of electrical activity by deleting synapses when neuronal activity is too high and by providing new synaptic contacts when activity is too low. Using our Model of Structural Plasticity, we explored how local changes in connectivity induced by a focal loss of input affected global network topology. In accordance with experimental and clinical data, we found that after partial deafferentation, the network as a whole became more random, although it maintained its small-world topology, while deafferentated neurons increased their betweenness centrality as they rewired and returned to the homeostatic range of activity. Furthermore, deafferentated neurons increased their global but decreased their local efficiency and got longer tailed degree distributions, indicating the emergence of hub neurons. Together, our results suggest that homeostatic structural plasticity may be an important driving force for lesion-induced network reorganization and that the increase in betweenness centrality of deafferentated areas may hold as a biomarker for brain repair.
Collapse
Affiliation(s)
- Markus Butz
- Simulation Lab Neuroscience - Bernstein Facility for Simulation and Database Technology, Institute for Advanced Simulation, Jülich Aachen Research Alliance, Forschungszentrum Jülich Jülich, Germany
| | - Ines D Steenbuck
- Student of the Medical Faculty, University of Freiburg Freiburg, Germany
| | - Arjen van Ooyen
- Department of Integrative Neurophysiology, VU University Amsterdam Amsterdam, Netherlands
| |
Collapse
|
94
|
Felling RJ, Song H. Epigenetic mechanisms of neuroplasticity and the implications for stroke recovery. Exp Neurol 2014; 268:37-45. [PMID: 25263580 DOI: 10.1016/j.expneurol.2014.09.017] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 09/09/2014] [Accepted: 09/14/2014] [Indexed: 01/06/2023]
Abstract
Ischemic stroke is a devastating brain injury and an important cause of neurologic disability worldwide and across the lifespan. Despite the physical, social, and economic burdens of this disease there is only a single approved medicine for the treatment of acute stroke, and its use is unfortunately limited to the small fraction of patients presenting within the narrow therapeutic window. Following stroke, there is a period of plasticity involving cell genesis, axon growth, and synaptic modulation that is essential to spontaneous recovery. Treatments focusing on neuroprotection and enhancing recovery have been the focus of intense preclinical studies, but translation of these treatments into clinical use has been disappointing thus far. The important role of epigenetic mechanisms in disease states is becoming increasingly apparent, including in ischemic stroke. These regulators of gene expression are poised to be critical mediators of recovery following stroke. In this review we discuss evidence for the role of epigenetics in neuroplasticity and the implications for stroke recovery.
Collapse
Affiliation(s)
- Ryan J Felling
- Department of Neurology, Johns Hopkins University School of Medicine, 200 N. Wolfe Street, Baltimore, MD 21286, USA.
| | - Hongjun Song
- Department of Neurology, Johns Hopkins University School of Medicine, 200 N. Wolfe Street, Baltimore, MD 21286, USA; Institute for Cell Engineering, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA; The Solomon Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
| |
Collapse
|
95
|
Chen J, Venkat P, Zacharek A, Chopp M. Neurorestorative therapy for stroke. Front Hum Neurosci 2014; 8:382. [PMID: 25018718 PMCID: PMC4072966 DOI: 10.3389/fnhum.2014.00382] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Accepted: 05/14/2014] [Indexed: 12/29/2022] Open
Abstract
Ischemic stroke is responsible for many deaths and long-term disability world wide. Development of effective therapy has been the target of intense research. Accumulating preclinical literature has shown that substantial functional improvement after stroke can be achieved using subacutely administered cell-based and pharmacological therapies. This review will discuss some of the latest findings on bone marrow-derived mesenchymal stem cells (BMSCs), human umbilical cord blood cells, and off-label use of some pharmacological agents, to promote recovery processes in the sub-acute and chronic phases following stroke. This review paper also focuses on molecular mechanisms underlying the cell-based and pharmacological restorative processes, which enhance angiogenesis, arteriogenesis, neurogenesis, and white matter remodeling following cerebral ischemia as well as an analysis of the interaction/coupling among these restorative events. In addition, the role of microRNAs mediating the intercellular communication between exogenously administered cells and parenchymal cells, and their effects on the regulation of angiogenesis and neuronal progenitor cell proliferation and differentiation, and brain plasticity after stroke are described.
Collapse
Affiliation(s)
- Jieli Chen
- Department of Neurology, Henry Ford Hospital , Detroit, MI , USA
| | - Poornima Venkat
- Department of Neurology, Henry Ford Hospital , Detroit, MI , USA ; Department of Physics, Oakland University , Rochester, MI , USA
| | - Alex Zacharek
- Department of Neurology, Henry Ford Hospital , Detroit, MI , USA
| | - Michael Chopp
- Department of Neurology, Henry Ford Hospital , Detroit, MI , USA ; Department of Physics, Oakland University , Rochester, MI , USA
| |
Collapse
|
96
|
Xerri C, Zennou-Azogui Y. Early and moderate sensory stimulation exerts a protective effect on perilesion representations of somatosensory cortex after focal ischemic damage. PLoS One 2014; 9:e99767. [PMID: 24914807 PMCID: PMC4051766 DOI: 10.1371/journal.pone.0099767] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 05/19/2014] [Indexed: 02/05/2023] Open
Abstract
Previous studies have shown that intensive training within an early critical time window after focal cortical ischemia increases the area of damaged tissue and is detrimental to behavioral recovery. We postulated that moderate stimulation initiated soon after the lesion could have protective effects on peri-infarct cortical somatotopic representations. Therefore, we have assessed the effects of mild cutaneous stimulation delivered in an attention-demanding behavioral context on the functional organization of the perilesion somatosensory cortex using high-density electrophysiological mapping. We compared the effects of 6-day training initiated on the 3rd day postlesion (early training; ET) to those of same-duration training started on the 8th day (delayed training; DT). Our findings confirm previous work showing that the absence of training aggravates representational loss in the perilesion zone. In addition, ET was found to be sufficient to limit expansion of the ischemic lesion and reduce tissue loss, and substantially maintain the neuronal responsiveness to tactile stimulation, thereby preserving somatotopic map arrangement in the peri-infarct cortical territories. By contrast, DT did not prevent tissue loss and only partially reinstated lost representations in a use-dependent manner within the spared peri-infarct cortical area. This study differentiates the effects of early versus delayed training on perilesion tissue and cortical map reorganization, and underscores the neuroprotective influence of mild rehabilitative stimulation on neuronal response properties in the peri-infarct cortex during an early critical period.
Collapse
Affiliation(s)
- Christian Xerri
- Neurosciences Intégratives et Adaptatives, Aix-Marseille Université, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7260, Fédération de Recherches Comportement-Cerveau-Cognition 3512, Marseille, France
- * E-mail:
| | - Yoh'i Zennou-Azogui
- Neurosciences Intégratives et Adaptatives, Aix-Marseille Université, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 7260, Fédération de Recherches Comportement-Cerveau-Cognition 3512, Marseille, France
| |
Collapse
|
97
|
Abela E, Seiler A, Missimer JH, Federspiel A, Hess CW, Sturzenegger M, Weder BJ, Wiest R. Grey matter volumetric changes related to recovery from hand paresis after cortical sensorimotor stroke. Brain Struct Funct 2014; 220:2533-50. [PMID: 24906703 PMCID: PMC4549385 DOI: 10.1007/s00429-014-0804-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 05/17/2014] [Indexed: 12/29/2022]
Abstract
Preclinical studies using animal models have shown that grey matter plasticity in both perilesional and distant neural networks contributes to behavioural recovery of sensorimotor functions after ischaemic cortical stroke. Whether such morphological changes can be detected after human cortical stroke is not yet known, but this would be essential to better understand post-stroke brain architecture and its impact on recovery. Using serial behavioural and high-resolution magnetic resonance imaging (MRI) measurements, we tracked recovery of dexterous hand function in 28 patients with ischaemic stroke involving the primary sensorimotor cortices. We were able to classify three recovery subgroups (fast, slow, and poor) using response feature analysis of individual recovery curves. To detect areas with significant longitudinal grey matter volume (GMV) change, we performed tensor-based morphometry of MRI data acquired in the subacute phase, i.e. after the stage compromised by acute oedema and inflammation. We found significant GMV expansion in the perilesional premotor cortex, ipsilesional mediodorsal thalamus, and caudate nucleus, and GMV contraction in the contralesional cerebellum. According to an interaction model, patients with fast recovery had more perilesional than subcortical expansion, whereas the contrary was true for patients with impaired recovery. Also, there were significant voxel-wise correlations between motor performance and ipsilesional GMV contraction in the posterior parietal lobes and expansion in dorsolateral prefrontal cortex. In sum, perilesional GMV expansion is associated with successful recovery after cortical stroke, possibly reflecting the restructuring of local cortical networks. Distant changes within the prefrontal-striato-thalamic network are related to impaired recovery, probably indicating higher demands on cognitive control of motor behaviour.
Collapse
Affiliation(s)
- E. Abela
- Support Center for Advanced Neuroimaging (SCAN), Institute for Diagnostic and Interventional Neuroradiology, University Hospital Inselspital and University of Bern, Bern, Switzerland
- Department of Neurology, Kantonsspital St. Gallen, St. Gallen, Switzerland
| | - A. Seiler
- Support Center for Advanced Neuroimaging (SCAN), Institute for Diagnostic and Interventional Neuroradiology, University Hospital Inselspital and University of Bern, Bern, Switzerland
| | - J. H. Missimer
- Laboratory of Biomolecular Research, Paul Scherrer Institute, Villigen, Switzerland
| | - A. Federspiel
- Department of Psychiatric Neurophysiology, University Hospital of Psychiatry and University of Bern, Bern, Switzerland
| | - C. W. Hess
- Department of Neurology, University Hospital Inselspital and University of Bern, Bern, Switzerland
| | - M. Sturzenegger
- Department of Neurology, University Hospital Inselspital and University of Bern, Bern, Switzerland
| | - B. J. Weder
- Support Center for Advanced Neuroimaging (SCAN), Institute for Diagnostic and Interventional Neuroradiology, University Hospital Inselspital and University of Bern, Bern, Switzerland
- Department of Neurology, Kantonsspital St. Gallen, St. Gallen, Switzerland
| | - R. Wiest
- Support Center for Advanced Neuroimaging (SCAN), Institute for Diagnostic and Interventional Neuroradiology, University Hospital Inselspital and University of Bern, Bern, Switzerland
| |
Collapse
|
98
|
Bauer AQ, Kraft AW, Wright PW, Snyder AZ, Lee JM, Culver JP. Optical imaging of disrupted functional connectivity following ischemic stroke in mice. Neuroimage 2014; 99:388-401. [PMID: 24862071 DOI: 10.1016/j.neuroimage.2014.05.051] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Revised: 05/12/2014] [Accepted: 05/18/2014] [Indexed: 01/13/2023] Open
Abstract
Recent human neuroimaging studies indicate that spontaneous fluctuations in neural activity, as measured by functional connectivity magnetic resonance imaging (fcMRI), are significantly affected following stroke. Disrupted functional connectivity is associated with behavioral deficits and has been linked to long-term recovery potential. FcMRI studies of stroke in rats have generally produced similar findings, although subacute cortical reorganization following focal ischemia appears to be more rapid than in humans. Similar studies in mice have not been published, most likely because fMRI in the small mouse brain is technically challenging. Extending functional connectivity methods to mouse models of stroke could provide a valuable tool for understanding the link between molecular mechanisms of stroke repair and human fcMRI findings at the system level. We applied functional connectivity optical intrinsic signal imaging (fcOIS) to mice before and 72 h after transient middle cerebral artery occlusion (tMCAO) to examine how graded ischemic injury affects the relationship between functional connectivity and infarct volume, stimulus-induced response, and behavior. Regional changes in functional connectivity within the MCA territory were largely proportional to infarct volume. However, subcortical damage affected functional connectivity in the somatosensory cortex as much as larger infarcts of cortex and subcortex. The extent of injury correlated with cortical activations following electrical stimulation of the affected forelimb and with functional connectivity in the somatosensory cortex. Regional homotopic functional connectivity in motor cortex correlated with behavioral deficits measured using an adhesive patch removal test. Spontaneous hemodynamic activity within the infarct exhibited altered temporal and spectral features in comparison to intact tissue; failing to account for these regional differences significantly affected apparent post-stroke functional connectivity measures. Thus, several results were strongly dependent on how the resting-state data were processed. Specifically, global signal regression alone resulted in apparently distorted functional connectivity measures in the intact hemisphere. These distortions were corrected by regressing out multiple sources of variance, as performed in human fcMRI. We conclude that fcOIS provides a sensitive imaging modality in the murine stroke model; however, it is necessary to properly account for altered hemodynamics in injured brain to obtain accurate measures of functional connectivity.
Collapse
Affiliation(s)
- Adam Q Bauer
- Department of Radiology, Washington University, Saint Louis, MO 63110, USA.
| | - Andrew W Kraft
- Department of Neurology, Washington University, Saint Louis, MO 63110, USA.
| | - Patrick W Wright
- Department of Radiology, Washington University, Saint Louis, MO 63110, USA; Department of Neurology, Washington University, Saint Louis, MO 63110, USA; Biomedical Engineering, Washington University, Saint Louis, MO 63110, USA.
| | - Abraham Z Snyder
- Department of Radiology, Washington University, Saint Louis, MO 63110, USA; Department of Neurology, Washington University, Saint Louis, MO 63110, USA.
| | - Jin-Moo Lee
- Department of Radiology, Washington University, Saint Louis, MO 63110, USA; Department of Neurology, Washington University, Saint Louis, MO 63110, USA; Biomedical Engineering, Washington University, Saint Louis, MO 63110, USA.
| | - Joseph P Culver
- Department of Radiology, Washington University, Saint Louis, MO 63110, USA; Biomedical Engineering, Washington University, Saint Louis, MO 63110, USA; Department of Physics, Washington University, Saint Louis, MO 63110, USA.
| |
Collapse
|
99
|
Adult cortical plasticity following injury: Recapitulation of critical period mechanisms? Neuroscience 2014; 283:4-16. [PMID: 24791715 DOI: 10.1016/j.neuroscience.2014.04.029] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 04/16/2014] [Accepted: 04/17/2014] [Indexed: 12/12/2022]
Abstract
A primary goal of research on developmental critical periods (CPs) is the recapitulation of a juvenile-like state of malleability in the adult brain that might enable recovery from injury. These ambitions are often framed in terms of the simple reinstatement of enhanced plasticity in the growth-restricted milieu of an injured adult brain. Here, we provide an analysis of the similarities and differences between deprivation-induced and injury-induced cortical plasticity, to provide for a nuanced comparison of these remarkably similar processes. As a first step, we review the factors that drive ocular dominance plasticity in the primary visual cortex of the uninjured brain during the CP and in adults, to highlight processes that might confer adaptive advantage. In addition, we directly compare deprivation-induced cortical plasticity during the CP and plasticity following acute injury or ischemia in mature brain. We find that these two processes display a biphasic response profile following deprivation or injury: an initial decrease in GABAergic inhibition and synapse loss transitions into a period of neurite expansion and synaptic gain. This biphasic response profile emphasizes the transition from a period of cortical healing to one of reconnection and recovery of function. Yet while injury-induced plasticity in adult shares several salient characteristics with deprivation-induced plasticity during the CP, the degree to which the adult injured brain is able to functionally rewire, and the time required to do so, present major limitations for recovery. Attempts to recapitulate a measure of CP plasticity in an adult injury context will need to carefully dissect the circuit alterations and plasticity mechanisms involved while measuring functional behavioral output to assess their ultimate success.
Collapse
|
100
|
Grefkes C, Fink GR. Connectivity-based approaches in stroke and recovery of function. Lancet Neurol 2014; 13:206-16. [PMID: 24457190 DOI: 10.1016/s1474-4422(13)70264-3] [Citation(s) in RCA: 349] [Impact Index Per Article: 34.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
After focal damage, cerebral networks reorganise their structural and functional anatomy to compensate for both the lesion itself and remote effects. Novel developments in the analysis of functional neuroimaging data enable us to assess in vivo the specific contributions of individual brain areas to recovery of function and the effect of treatment on cortical reorganisation. Connectivity analyses can be used to investigate the effect of stroke on cerebral networks, and help us to understand why some patients make a better recovery than others. This systems-level view also provides insights into how neuromodulatory interventions might target pathological network configurations associated with incomplete recovery. In the future, such analyses of connectivity could help to optimise treatment regimens based on the individual network pathology underlying a particular neurological deficit, thereby opening the way for stratification of patients based on the possible response to an intervention.
Collapse
Affiliation(s)
- Christian Grefkes
- Department of Neurology, University Hospital Cologne, Köln, Germany; Neuromodulation and Neurorehabilitation, Max Planck Institute for Neurological Research, Köln, Germany; Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Centre Jülich, Jülich, Germany.
| | - Gereon R Fink
- Department of Neurology, University Hospital Cologne, Köln, Germany; Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Centre Jülich, Jülich, Germany
| |
Collapse
|