1
|
Martín-Lopez G, Mallavibarrena PR, Villa-Gonzalez M, Vidal N, Pérez-Alvarez MJ. The dynamics of oligodendrocyte populations following permanent ischemia promotes long-term spontaneous remyelination of damaged area. Biochim Biophys Acta Mol Basis Dis 2024:167270. [PMID: 38823461 DOI: 10.1016/j.bbadis.2024.167270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 05/10/2024] [Accepted: 05/25/2024] [Indexed: 06/03/2024]
Abstract
Stroke is a major public health concern, with limited clinically approved interventions available to enhance sensorimotor recovery beyond reperfusion. Remarkably, spontaneous recovery is observed in certain stroke patients, suggesting the existence of a brain self-repair mechanism not yet fully understood. In a rat model of permanent cerebral ischemia, we described an increase in oligodendrocytes expressing 3RTau in damaged area. Considering that restoration of myelin integrity ameliorates symptoms in many neurodegenerative diseases, here we hypothesize that this cellular response could trigger remyelination. Our results revealed after ischemia an early recruitment of OPCs to damaged area, followed by their differentiation into 3RTau+ pre-myelinating cells and subsequent into remyelinating oligodendrocytes. Using rat brain slices and mouse primary culture we confirmed the presence of 3RTau in pre-myelinating and a subset of mature oligodendrocytes. The myelin status analysis confirmed long-term remyelination in the damaged area. Postmortem samples from stroke subjects showed a reduction in oligodendrocytes, 3RTau+ cells, and myelin complexity in subcortical white matter. In conclusion, the dynamics of oligodendrocyte populations after ischemia reveals a spontaneous brain self-repair mechanism which restores the functionality of neuronal circuits long-term by remyelination of damaged area. This is evidenced by the improvement of sensorimotor functions in ischemic rats. A deep understanding of this mechanism could be valuable in the search for alternative oligodendrocyte-based, therapeutic interventions to reduce the effects of stroke.
Collapse
Affiliation(s)
- Gerardo Martín-Lopez
- Departamento de Biología (Fisiología Animal), Facultad de Ciencias, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Paula R Mallavibarrena
- Departamento de Biología (Fisiología Animal), Facultad de Ciencias, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Mario Villa-Gonzalez
- Departamento de Biología (Fisiología Animal), Facultad de Ciencias, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Noemi Vidal
- Departamento de Patología, Hospital Universitari de Bellvitge, L'Hospitalet de Llobregat, 08907 Barcelona, Spain
| | - Maria José Pérez-Alvarez
- Departamento de Biología (Fisiología Animal), Facultad de Ciencias, Universidad Autónoma de Madrid, 28049 Madrid, Spain; Instituto Universitario de Biología Molecular (IUBM), Universidad Autónoma de Madrid, Centro de Biología Molecular Severo Ochoa (CBM), Departamento de Neuropatología Molecular UAM-CSIC, 28049 Madrid, Spain.
| |
Collapse
|
2
|
Huang Z, Jordan JD, Zhang Q. Myelin Pathology in Alzheimer's Disease: Potential Therapeutic Opportunities. Aging Dis 2024; 15:698-713. [PMID: 37548935 PMCID: PMC10917545 DOI: 10.14336/ad.2023.0628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 06/28/2023] [Indexed: 08/08/2023] Open
Abstract
Alzheimer's disease (AD) is an age-related neurodegenerative disease characterized by memory loss and cognitive decline. Despite significant efforts over several decades, our understanding of the pathophysiology of this disease is still incomplete. Myelin is a multi-layered membrane structure ensheathing neuronal axons, which is essential for the fast and effective propagation of action potentials along the axons. Recent studies highlight the critical involvement of myelin in memory consolidation and reveal its vulnerability in various pathological conditions. Notably, apart from the classic amyloid hypothesis, myelin degeneration has been proposed as another critical pathophysiological feature of AD, which could occur prior to the development of amyloid pathology. Here, we review recent works supporting the critical role of myelin in cognition and myelin pathology during AD progression, with a focus on the mechanisms underlying myelin degeneration in AD. We also discuss the complex intersections between myelin pathology and typical AD pathophysiology, as well as the therapeutic potential of pro-myelinating approaches for this disease. Overall, these findings implicate myelin degeneration as a critical contributor to AD-related cognitive deficits and support targeting myelin repair as a promising therapeutic strategy for AD.
Collapse
Affiliation(s)
- Zhihai Huang
- Department of Neurology, Louisiana State University Health Sciences Center, Shreveport, LA 71103 USA
| | - J. Dedrick Jordan
- Department of Neurology, Louisiana State University Health Sciences Center, Shreveport, LA 71103 USA
| | - Quanguang Zhang
- Department of Neurology, Louisiana State University Health Sciences Center, Shreveport, LA 71103 USA
| |
Collapse
|
3
|
Wang Y, Yang Z, Wang R, Zheng Y, Han Z, Fan J, Yan F, Liu P, Luo Y. Annexin A6 mitigates neurological deficit in ischemia/reperfusion injury by promoting synaptic plasticity. CNS Neurosci Ther 2024; 30:e14639. [PMID: 38380783 PMCID: PMC10880127 DOI: 10.1111/cns.14639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Revised: 01/16/2024] [Accepted: 01/31/2024] [Indexed: 02/22/2024] Open
Abstract
AIMS Alleviating neurological dysfunction caused by acute ischemic stroke (AIS) remains intractable. Given Annexin A6 (ANXA6)'s potential in promoting axon branching and repairing cell membranes, the study aimed to explore ANXA6's potential in alleviating AIS-induced neurological dysfunction. METHODS A mouse middle cerebral artery occlusion model was established. Brain and plasma ANXA6 levels were detected at different timepoints post ischemia/reperfusion (I/R). We overexpressed and down-regulated brain ANXA6 and evaluated infarction volume, neurological function, and synaptic plasticity-related proteins post I/R. Plasma ANXA6 levels were measured in patients with AIS and healthy controls, investigating ANXA6 expression's clinical significance. RESULTS Brain ANXA6 levels initially decreased, gradually returning to normal post I/R; plasma ANXA6 levels showed an opposite trend. ANXA6 overexpression significantly decreased the modified neurological severity score (p = 0.0109) 1 day post I/R and the infarction area at 1 day (p = 0.0008) and 7 day (p = 0.0013) post I/R, and vice versa. ANXA6 positively influenced synaptic plasticity, upregulating synaptophysin (p = 0.006), myelin basic protein (p = 0.010), neuroligin (p = 0.078), and tropomyosin-related kinase B (p = 0.150). Plasma ANXA6 levels were higher in patients with AIS (1.969 [1.228-3.086]) compared to healthy controls (1.249 [0.757-2.226]) (p < 0.001), that served as an independent risk factor for poor AIS outcomes (2.120 [1.563-3.023], p < 0.001). CONCLUSIONS This study is the first to suggest that ANXA6 enhances synaptic plasticity and protects against transient cerebral ischemia.
Collapse
Affiliation(s)
- Yilin Wang
- Institute of Cerebrovascular Disease Research and Department of NeurologyXuanwu Hospital of Capital Medical UniversityBeijingChina
| | - Zhenhong Yang
- Institute of Cerebrovascular Disease Research and Department of NeurologyXuanwu Hospital of Capital Medical UniversityBeijingChina
| | - Rongliang Wang
- Institute of Cerebrovascular Disease Research and Department of NeurologyXuanwu Hospital of Capital Medical UniversityBeijingChina
| | - Yangmin Zheng
- Institute of Cerebrovascular Disease Research and Department of NeurologyXuanwu Hospital of Capital Medical UniversityBeijingChina
| | - Ziping Han
- Institute of Cerebrovascular Disease Research and Department of NeurologyXuanwu Hospital of Capital Medical UniversityBeijingChina
| | - Junfen Fan
- Institute of Cerebrovascular Disease Research and Department of NeurologyXuanwu Hospital of Capital Medical UniversityBeijingChina
| | - Feng Yan
- Institute of Cerebrovascular Disease Research and Department of NeurologyXuanwu Hospital of Capital Medical UniversityBeijingChina
| | - Ping Liu
- Institute of Cerebrovascular Disease Research and Department of NeurologyXuanwu Hospital of Capital Medical UniversityBeijingChina
| | - Yumin Luo
- Institute of Cerebrovascular Disease Research and Department of NeurologyXuanwu Hospital of Capital Medical UniversityBeijingChina
- Beijing Institute for Brain DisordersBeijingChina
| |
Collapse
|
4
|
Prehn A, Hobusch C, Härtig W, Michalski D, Krueger M, Flachmeyer B. Increasing reproducibility in preclinical stroke research: the correlation of immunofluorescence intensity measurements and Western blot analyses strongly depends on antibody clonality and tissue pre-treatment in a mouse model of focal cerebral ischemia. Front Cell Neurosci 2023; 17:1183232. [PMID: 37342767 PMCID: PMC10277931 DOI: 10.3389/fncel.2023.1183232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 05/16/2023] [Indexed: 06/23/2023] Open
Abstract
In the setting of stroke, ischemia not only impairs neuronal function, but also detrimentally affects the different components of the neurovascular unit, which are shown to be involved in the transition from reversible to long-lasting tissue damage. In this context, the glial proteins myelin basic protein (MBP) and the 2',3'-cyclic-nucleotide 3'-phosphodiesterase (CNP) as well as the vasculature-associated basement membrane proteins laminin and collagen IV have been identified as ischemia-sensitive elements. However, available data from immunofluorescence and Western blot analyses are often found to be contradictory, which renders interpretation of the respective data rather difficult. Therefore, the present study investigates the impact of tissue pre-treatment and antibody clonality on immunofluorescence measurements of the mentioned proteins in a highly reproducible model of permanent middle cerebral artery occlusion. Here, immunofluorescence labeling using polyclonal antibodies revealed an increased immunofluorescence intensity of MBP, CNP, laminin and collagen IV in ischemic areas, although Western blot analyses did not reveal increased protein levels. Importantly, contrary to polyclonal antibodies, monoclonal ones did not provide increased fluorescence intensities in ischemic areas. Further, we were able to demonstrate that different ways of tissue pre-treatment including paraformaldehyde fixation and antigen retrieval may not only impact on fluorescence intensity measurements in general, but rather one-sidedly affect either ischemic or unaffected tissue. Therefore, immunofluorescence intensity measurements do not necessarily correlate with the actual protein levels, especially in ischemia-affected tissue and should always be complemented by different techniques to enhance reproducibility and to hopefully overcome the translational roadblock from bench to bedside.
Collapse
Affiliation(s)
- Anna Prehn
- Institute of Anatomy, Leipzig University, Leipzig, Germany
| | | | - Wolfgang Härtig
- Paul Flechsig Institute of Brain Research, Leipzig University, Leipzig, Germany
| | | | - Martin Krueger
- Institute of Anatomy, Leipzig University, Leipzig, Germany
| | | |
Collapse
|
5
|
Shpakov AO, Zorina II, Derkach KV. Hot Spots for the Use of Intranasal Insulin: Cerebral Ischemia, Brain Injury, Diabetes Mellitus, Endocrine Disorders and Postoperative Delirium. Int J Mol Sci 2023; 24:3278. [PMID: 36834685 PMCID: PMC9962062 DOI: 10.3390/ijms24043278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/27/2023] [Accepted: 01/31/2023] [Indexed: 02/11/2023] Open
Abstract
A decrease in the activity of the insulin signaling system of the brain, due to both central insulin resistance and insulin deficiency, leads to neurodegeneration and impaired regulation of appetite, metabolism, endocrine functions. This is due to the neuroprotective properties of brain insulin and its leading role in maintaining glucose homeostasis in the brain, as well as in the regulation of the brain signaling network responsible for the functioning of the nervous, endocrine, and other systems. One of the approaches to restore the activity of the insulin system of the brain is the use of intranasally administered insulin (INI). Currently, INI is being considered as a promising drug to treat Alzheimer's disease and mild cognitive impairment. The clinical application of INI is being developed for the treatment of other neurodegenerative diseases and improve cognitive abilities in stress, overwork, and depression. At the same time, much attention has recently been paid to the prospects of using INI for the treatment of cerebral ischemia, traumatic brain injuries, and postoperative delirium (after anesthesia), as well as diabetes mellitus and its complications, including dysfunctions in the gonadal and thyroid axes. This review is devoted to the prospects and current trends in the use of INI for the treatment of these diseases, which, although differing in etiology and pathogenesis, are characterized by impaired insulin signaling in the brain.
Collapse
Affiliation(s)
- Alexander O. Shpakov
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, 194223 St. Petersburg, Russia
| | | | | |
Collapse
|
6
|
Guo X, Jin X, Han K, Kang S, Tian S, Lv X, Feng M, Zheng H, Zuo Y, Xu G, Hu M, Xu J, Lv P, Chang YZ. Iron promotes neurological function recovery in mice with ischemic stroke through endogenous repair mechanisms. Free Radic Biol Med 2022; 182:59-72. [PMID: 35202785 DOI: 10.1016/j.freeradbiomed.2022.02.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 02/16/2022] [Accepted: 02/17/2022] [Indexed: 11/17/2022]
Abstract
The endogenous repair mechanisms play an important role in the recovery of nerve function after stroke, such as gliosis, synaptic plasticity, remyelination and nerve regeneration. Iron is the most abundant trace metal element in the brain and plays a crucial role in the maintenance of normal cerebral function. It is an important coenzyme factor in the process of cell metabolism, DNA synthesis, purine catabolism and neurotransmitter synthesis and decomposition. However, it is unclear what role iron plays in the long-term recovery of neurological function after stroke. In this study, we first observed that changes in iron metabolism occurred during neurological function recovery in the mice with distal middle cerebral artery occlusion (dMCAO). Our data showed that plasticity changes due to endogenous repair mechanisms resulted in improvements in cerebral cortex function. These changes involved gliosis, synaptic function reconstruction, remyelination, and activation of neural stem cells. In order to examine the potential role of iron, we synthesized liposomal-encapsulated deferoxamine (DFO) nanoparticles to further explore the effect and the mechanism of iron on the recovery of neurological function in dMCAO mice. Our results showed that liposome-DFO decreased iron deposition and reversed plasticity changes in cerebral cortex function after stroke, which delayed neurological function recovery. This experiment shows that the increasing iron level promotes endogenous repair in ischemic stroke. Our finding reveals the change regularity of iron and emphasizes the beneficial role of iron in the recovery process of neurological function, which provides an important basis for the prevention and/or treatment of ischemia-reperfusion and recovery after stroke.
Collapse
Affiliation(s)
- Xin Guo
- Department of Neurology, Hebei Medical University, Shijiazhuang, 050017, Hebei, China; Laboratory of Molecular Iron Metabolism, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, Hebei, China
| | - Xiaofang Jin
- Laboratory of Molecular Iron Metabolism, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, Hebei, China
| | - Kang Han
- Laboratory of Molecular Iron Metabolism, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, Hebei, China
| | - Shaomeng Kang
- Laboratory of Molecular Iron Metabolism, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, Hebei, China
| | - Siyu Tian
- Laboratory of Molecular Iron Metabolism, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, Hebei, China
| | - Xin Lv
- Laboratory of Molecular Iron Metabolism, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, Hebei, China
| | - Mudi Feng
- Laboratory of Molecular Iron Metabolism, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, Hebei, China
| | - Huiwen Zheng
- Laboratory of Molecular Iron Metabolism, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, Hebei, China
| | - Yong Zuo
- Laboratory of Molecular Iron Metabolism, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, Hebei, China
| | - Guodong Xu
- Department of Neurology, Hebei General Hospital; Shijiazhuang 050051, Hebei, China
| | - Ming Hu
- Department of Neurology, Hebei General Hospital; Shijiazhuang 050051, Hebei, China
| | - Jing Xu
- Department of Neurology, Hebei General Hospital; Shijiazhuang 050051, Hebei, China
| | - Peiyuan Lv
- Department of Neurology, Hebei Medical University, Shijiazhuang, 050017, Hebei, China; Department of Neurology, Hebei General Hospital; Shijiazhuang 050051, Hebei, China.
| | - Yan-Zhong Chang
- Laboratory of Molecular Iron Metabolism, College of Life Sciences, Hebei Normal University, Shijiazhuang, 050024, Hebei, China.
| |
Collapse
|
7
|
Zhao H, Liu ZD, Zhang YB, Gao XY, Wang C, Liu Y, Wang XF. NEP1‑40 promotes myelin regeneration via upregulation of GAP‑43 and MAP‑2 expression after focal cerebral ischemia in rats. Mol Med Rep 2021; 24:844. [PMID: 34643252 PMCID: PMC8524407 DOI: 10.3892/mmr.2021.12484] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 09/08/2021] [Indexed: 01/26/2023] Open
Abstract
Axon regeneration after lesions to the central nervous system (CNS) is largely limited by the presence of growth inhibitory molecules expressed in myelin. Nogo‑A is a principal inhibitor of neurite outgrowth, and blocking the activity of Nogo‑A can induce axonal sprouting and functional recovery. However, there are limited data on the expression of Nogo‑A after CNS lesions, and the mechanism underlying its influences on myelin growth remains unknown. The aim of the present study was to observe the time course of Nogo‑A after cerebral ischemia/reperfusion in rats using immunohistochemistry and western blot techniques, and to test the effect of its inhibitor Nogo extracellular peptide 1‑40 (NEP1‑40) on neural plasticity proteins, growth‑associated binding protein 43 (GAP‑43) and microtubule associated protein 2 (MAP‑2), as a possible mechanism underlying myelin suppression. A classic model of middle cerebral artery occlusion (MCAO) was established in Sprague‑Dawley rats, which were divided into three groups: i) MCAO model group; ii) MCAO + saline group; and iii) MCAO + NEP1‑40 group. Rats of each group were divided into five subgroups by time points as follows: days 1, 3, 7, 14 and 28. Animals that only received sham operation were used as controls. The Nogo‑A immunoreactivity was located primarily in the cytoplasm of oligodendrocytes. The number of Nogo‑A immunoreactive cells significantly increased from day 1 to day 3 after MCAO, nearly returning to the control level at day 7, increased again at day 14 and decreased at day 28. Myelin basic protein (MBP) immunoreactivity in the ipsilateral striatum gradually decreased from day 1 to day 28 after ischemia, indicating myelin loss appeared at early time points and continuously advanced during ischemia. Then, intracerebroventricular infusion of NEP1‑40, which is a Nogo‑66 receptor antagonist peptide, was administered at days 1, 3 and 14 after MCAO. It was observed that GAP‑43 considerably increased from day 1 to day 7 and then decreased to a baseline level at day 28 compared with the control. MAP‑2 expression across days 1‑28 significantly decreased after MCAO. Administration of NEP1‑40 attenuated the reduction of MBP, and upregulated GAP‑43 and MAP‑2 expression at the corresponding time points after MCAO compared with the MCAO + saline group. The present results indicated that NEP1‑40 ameliorated myelin damage and promoted regeneration by upregulating the expression of GAP‑43 and MAP‑2 related to neuronal and axonal plasticity, which may aid with the identification of a novel molecular mechanism of restriction in CNS regeneration mediated by Nogo‑A after ischemia in rats.
Collapse
Affiliation(s)
- Hong Zhao
- Department of Neurology, Dalian Municipal Central Hospital Affiliated to Dalian Medical University, Dalian, Liaoning 116033, P.R. China,Correspondence to: Professor Hong Zhao, Department of Neurology, Dalian Municipal Central Hospital Affiliated to Dalian Medical University, 826 Xi Nan Road, Dalian, Liaoning 116033, P.R. China, E-mail:
| | - Zhen-Dong Liu
- Department of General Medicine, Central Hospital Affiliated to Shaoxing University, Shaoxing, Zhejiang 312000, P.R. China
| | - Yong-Bo Zhang
- Department of Neurology, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, P.R. China
| | - Xiao-Yu Gao
- Department of Neurology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, Shandong 264000, P.R. China
| | - Cui Wang
- Department of Neurology, Dalian Municipal Central Hospital Affiliated to Dalian Medical University, Dalian, Liaoning 116033, P.R. China
| | - Yi Liu
- Department of Neurology, Dalian Municipal Central Hospital Affiliated to Dalian Medical University, Dalian, Liaoning 116033, P.R. China
| | - Xun-Fen Wang
- Department of Neurology, Dalian Medical University, Dalian, Liaoning 116033, P.R. China
| |
Collapse
|
8
|
Damian C, Ghuman H, Mauney C, Azar R, Reinartz J, Badylak SF, Modo M. Post-Stroke Timing of ECM Hydrogel Implantation Affects Biodegradation and Tissue Restoration. Int J Mol Sci 2021; 22:ijms222111372. [PMID: 34768800 PMCID: PMC8583606 DOI: 10.3390/ijms222111372] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 10/13/2021] [Accepted: 10/17/2021] [Indexed: 01/01/2023] Open
Abstract
Extracellular matrix (ECM) hydrogel promotes tissue regeneration in lesion cavities after stroke. However, a bioscaffold's regenerative potential needs to be considered in the context of the evolving pathological environment caused by a stroke. To evaluate this key issue in rats, ECM hydrogel was delivered to the lesion core/cavity at 7-, 14-, 28-, and 90-days post-stroke. Due to a lack of tissue cavitation 7-days post-stroke, implantation of ECM hydrogel did not achieve a sufficient volume and distribution to warrant comparison with the other time points. Biodegradation of ECM hydrogel implanted 14- and 28-days post-stroke were efficiently (80%) degraded by 14-days post-bioscaffold implantation, whereas implantation 90-days post-stroke revealed only a 60% decrease. Macrophage invasion was robust at 14- and 28-days post-stroke but reduced in the 90-days post-stroke condition. The pro-inflammation (M1) and pro-repair (M2) phenotype ratios were equivalent at all time points, suggesting that the pathological environment determines macrophage invasion, whereas ECM hydrogel defines their polarization. Neural cells (neural progenitors, neurons, astrocytes, oligodendrocytes) were found at all time points, but a 90-days post-stroke implantation resulted in reduced densities of mature phenotypes. Brain tissue restoration is therefore dependent on an efficient delivery of a bioscaffold to a tissue cavity, with 28-days post-stroke producing the most efficient biodegradation and tissue regeneration, whereas by 90-days post-stroke, these effects are significantly reduced. Improving our understanding of how the pathological environment influences biodegradation and the tissue restoration process is hence essential to devise engineering strategies that could extend the therapeutic window for bioscaffolds to repair the damaged brain.
Collapse
Affiliation(s)
- Corina Damian
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA 15260, USA; (C.D.); (C.M.)
| | - Harmanvir Ghuman
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; (H.G.); (R.A.); (S.F.B.)
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Carrinton Mauney
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA 15260, USA; (C.D.); (C.M.)
| | - Reem Azar
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; (H.G.); (R.A.); (S.F.B.)
| | - Janina Reinartz
- Department of Radiology, University of Pittsburgh, Pittsburgh, PA 15260, USA;
| | - Stephen F. Badylak
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; (H.G.); (R.A.); (S.F.B.)
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15260, USA
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Michel Modo
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; (H.G.); (R.A.); (S.F.B.)
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15260, USA
- Department of Radiology, University of Pittsburgh, Pittsburgh, PA 15260, USA;
- Correspondence: ; Tel.: +1-(412)-383-7200
| |
Collapse
|
9
|
Berlet R, Anthony S, Brooks B, Wang ZJ, Sadanandan N, Shear A, Cozene B, Gonzales-Portillo B, Parsons B, Salazar FE, Lezama Toledo AR, Monroy GR, Gonzales-Portillo JV, Borlongan CV. Combination of Stem Cells and Rehabilitation Therapies for Ischemic Stroke. Biomolecules 2021; 11:1316. [PMID: 34572529 PMCID: PMC8468342 DOI: 10.3390/biom11091316] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/31/2021] [Accepted: 09/01/2021] [Indexed: 12/14/2022] Open
Abstract
Stem cell transplantation with rehabilitation therapy presents an effective stroke treatment. Here, we discuss current breakthroughs in stem cell research along with rehabilitation strategies that may have a synergistic outcome when combined together after stroke. Indeed, stem cell transplantation offers a promising new approach and may add to current rehabilitation therapies. By reviewing the pathophysiology of stroke and the mechanisms by which stem cells and rehabilitation attenuate this inflammatory process, we hypothesize that a combined therapy will provide better functional outcomes for patients. Using current preclinical data, we explore the prominent types of stem cells, the existing theories for stem cell repair, rehabilitation treatments inside the brain, rehabilitation modalities outside the brain, and evidence pertaining to the benefits of combined therapy. In this review article, we assess the advantages and disadvantages of using stem cell transplantation with rehabilitation to mitigate the devastating effects of stroke.
Collapse
Affiliation(s)
- Reed Berlet
- Chicago Medical School, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Rd, North Chicago, IL 60064, USA;
| | - Stefan Anthony
- Lake Erie College of Osteopathic Medicine, 5000 Lakewood Ranch Boulevard, Bradenton, FL 34211, USA;
| | - Beverly Brooks
- Department of Neurosurgery and Brain Repair, Morsani College of Medicine, University of South Florida, 12901 Bruce B Downs Blvd, Tampa, FL 33612, USA; (B.B.); (Z.-J.W.)
| | - Zhen-Jie Wang
- Department of Neurosurgery and Brain Repair, Morsani College of Medicine, University of South Florida, 12901 Bruce B Downs Blvd, Tampa, FL 33612, USA; (B.B.); (Z.-J.W.)
| | | | - Alex Shear
- University of Florida, 205 Fletcher Drive, Gainesville, FL 32611, USA;
| | - Blaise Cozene
- Tulane University, 6823 St. Charles Ave, New Orleans, LA 70118, USA;
| | | | - Blake Parsons
- Washington and Lee University, 204 W Washington St, Lexington, VA 24450, USA;
| | - Felipe Esparza Salazar
- Centro de Investigación en Ciencias de la Salud (CICSA), FCS, Universidad Anáhuac México Campus Norte, Huixquilucan 52786, Mexico; (F.E.S.); (A.R.L.T.); (G.R.M.)
| | - Alma R. Lezama Toledo
- Centro de Investigación en Ciencias de la Salud (CICSA), FCS, Universidad Anáhuac México Campus Norte, Huixquilucan 52786, Mexico; (F.E.S.); (A.R.L.T.); (G.R.M.)
| | - Germán Rivera Monroy
- Centro de Investigación en Ciencias de la Salud (CICSA), FCS, Universidad Anáhuac México Campus Norte, Huixquilucan 52786, Mexico; (F.E.S.); (A.R.L.T.); (G.R.M.)
| | | | - Cesario V. Borlongan
- Department of Neurosurgery and Brain Repair, Morsani College of Medicine, University of South Florida, 12901 Bruce B Downs Blvd, Tampa, FL 33612, USA; (B.B.); (Z.-J.W.)
- Center of Excellence for Aging and Brain Repair, Morsani College of Medicine, University of South Florida, 12901 Bruce B Downs Blvd, Tampa, FL 33612, USA
| |
Collapse
|
10
|
Ko E, Poon MLS, Park E, Cho Y, Shin JH. Engineering 3D Cortical Spheroids for an In Vitro Ischemic Stroke Model. ACS Biomater Sci Eng 2021; 7:3845-3860. [PMID: 34275269 DOI: 10.1021/acsbiomaterials.1c00406] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Three-dimensional (3D) spheroids composed of brain cells have shown great potential to mimic the pathophysiology of the brain. However, a 3D spheroidal brain-disease model for cerebral ischemia has not been reported. This study investigated an ultralow attachment (ULA) surface-mediated formation of 3D cortical spheroids using primary rat cortical cells to recapitulate the cerebral ischemic responses in stroke by oxygen-glucose deprivation-reoxygenation (OGD-R) treatment. Comparison between two-dimensional (2D) and 3D cell culture models confirmed the better performance of the 3D cortical spheroids as normal brain models. The cortical cells cultured in 3D maintained their healthy physiological morphology of a less activated state and suppressed mRNA expressions of pathological stroke markers, S100B, IL-1β, and MBP, selected based on in vivo stroke model. Interestingly, the spheroids formed on the ULA surface exhibited striking aggregation dynamics involving active cell-substrate interactions, whereas those formed on the agarose surface aggregated passively by the convective flow of the media. Accordingly, ULA spheroids manifested a layered arrangement of neurons and astrocytes with higher expressions of integrin β1, integrin α5, N-cadherin, and fibronectin than the agarose spheroids. OGD-R-induced stroke model of the ULA spheroids successfully mimicked the ischemic response as evidenced by the upregulated mRNA expressions of the key markers for stroke, S100B, IL-1β, and MBP. Our study suggested that structurally and functionally distinct cortical spheroids could be generated by simply tuning the cell-substrate binding activities during dynamic spheroidal formation, which should be an essential factor to consider in establishing a brain-disease model.
Collapse
Affiliation(s)
- Eunmin Ko
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, 291, Daehak-ro, Daejeon 34141, Republic of Korea
| | - Mong Lung Steve Poon
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, 291, Daehak-ro, Daejeon 34141, Republic of Korea
| | - Eunyoung Park
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, 291, Daehak-ro, Daejeon 34141, Republic of Korea
| | - Youngbin Cho
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, 291, Daehak-ro, Daejeon 34141, Republic of Korea
| | - Jennifer H Shin
- Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, 291, Daehak-ro, Daejeon 34141, Republic of Korea
| |
Collapse
|
11
|
Cellular Mechanisms Participating in Brain Repair of Adult Zebrafish and Mammals after Injury. Cells 2021; 10:cells10020391. [PMID: 33672842 PMCID: PMC7917790 DOI: 10.3390/cells10020391] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/28/2021] [Accepted: 02/05/2021] [Indexed: 12/12/2022] Open
Abstract
Adult neurogenesis is an evolutionary conserved process occurring in all vertebrates. However, striking differences are observed between the taxa, considering the number of neurogenic niches, the neural stem cell (NSC) identity, and brain plasticity under constitutive and injury-induced conditions. Zebrafish has become a popular model for the investigation of the molecular and cellular mechanisms involved in adult neurogenesis. Compared to mammals, the adult zebrafish displays a high number of neurogenic niches distributed throughout the brain. Furthermore, it exhibits a strong regenerative capacity without scar formation or any obvious disabilities. In this review, we will first discuss the similarities and differences regarding (i) the distribution of neurogenic niches in the brain of adult zebrafish and mammals (mainly mouse) and (ii) the nature of the neural stem cells within the main telencephalic niches. In the second part, we will describe the cascade of cellular events occurring after telencephalic injury in zebrafish and mouse. Our study clearly shows that most early events happening right after the brain injury are shared between zebrafish and mouse including cell death, microglia, and oligodendrocyte recruitment, as well as injury-induced neurogenesis. In mammals, one of the consequences following an injury is the formation of a glial scar that is persistent. This is not the case in zebrafish, which may be one of the main reasons that zebrafish display a higher regenerative capacity.
Collapse
|
12
|
Zolkefley MKI, Firwana YMS, Hatta HZM, Rowbin C, Nassir CMNCM, Hanafi MH, Abdullah MS, Mustapha M. An overview of fractional anisotropy as a reliable quantitative measurement for the corticospinal tract (CST) integrity in correlation with a Fugl-Meyer assessment in stroke rehabilitation. J Phys Ther Sci 2021; 33:75-83. [PMID: 33519079 PMCID: PMC7829559 DOI: 10.1589/jpts.33.75] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Accepted: 10/25/2020] [Indexed: 11/24/2022] Open
Abstract
[Purpose] Understanding the essential mechanisms in post-stroke recovery not only
provides important basic insights into brain function and plasticity but can also guide
the development of new therapeutic approaches for stroke patients. This review aims to
give an overview of how various variables of Magnetic Resonance-Diffusion Tensor Imaging
(MR-DTI) metrics of fractional anisotropy (FA) can be used as a reliable quantitative
measurement and indicator of corticospinal tract (CST) changes, particularly in relation
to functional motor outcome correlation with a Fugl-Meyer assessment in stroke
rehabilitation. [Methods] PubMed electronic database was searched for the relevant
literature, using key words of diffusion tensor imaging (dti), corticospinal tract, and
stroke. [Results] We reviewed the role of FA in monitoring CST remodeling and its role of
predicting motor recovery after stroke. We also discussed the mechanism of CST remodeling
and its modulation from the value of FA and FMA-UE. [Conclusion] Heterogeneity of
post-stroke brain disorganization and motor impairment is a recognized challenge in the
development of accurate indicators of CST integrity. DTI-based FA measurements offer a
reliable and evidence-based indicator for CST integrity that would aid in predicting motor
recovery within the context of stroke rehabilitation.
Collapse
Affiliation(s)
- Mohd Khairul Izamil Zolkefley
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia: 16150 Kubang Kerian, Kelantan, Malaysia
| | - Younis M S Firwana
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia: 16150 Kubang Kerian, Kelantan, Malaysia
| | - Hasnettty Zuria Mohamed Hatta
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia: 16150 Kubang Kerian, Kelantan, Malaysia.,Rehabilitation Unit, Hospital Universiti Sains Malaysia, Universiti Sains Malaysia, Malaysia
| | - Christina Rowbin
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia: 16150 Kubang Kerian, Kelantan, Malaysia.,Rehabilitation Unit, Hospital Universiti Sains Malaysia, Universiti Sains Malaysia, Malaysia
| | | | - Muhammad Hafiz Hanafi
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia: 16150 Kubang Kerian, Kelantan, Malaysia.,Rehabilitation Unit, Hospital Universiti Sains Malaysia, Universiti Sains Malaysia, Malaysia
| | - Mohd Shafie Abdullah
- Department of Radiology, School of Medical Sciences, Universiti Sains Malaysia, Malaysia
| | - Muzaimi Mustapha
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia: 16150 Kubang Kerian, Kelantan, Malaysia
| |
Collapse
|
13
|
Wang C, Chopp M, Huang R, Li C, Zhang Y, Golembieski W, Lu M, Hazan Z, Zhang ZG, Zhang L. Delayed (21 Days) Post Stroke Treatment With RPh201, a Botany-Derived Compound, Improves Neurological Functional Recovery in a Rat Model of Embolic Stroke. Front Neurosci 2020; 14:813. [PMID: 32848574 PMCID: PMC7412960 DOI: 10.3389/fnins.2020.00813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 07/10/2020] [Indexed: 11/13/2022] Open
Abstract
Background Despite the recent advances in the acute stroke care, treatment options for long-term disability are limited. RPh201 is a botany-derived bioactive compound that has been shown to exert beneficial effects in various experimental models of neural injury. The present study evaluated the effect of delayed RPh201 treatment on long term functional recovery after stroke. Methods Adult male Wistar rats subjected to embolic middle cerebral artery occlusion (MCAO) were randomized into the following experimental groups (n = 20/group): (1) RPh201 treatment, and (2) Vehicle (cottonseed oil). RPh201 (20 μl) or Vehicle were subcutaneously administered twice a week for 16 consecutive weeks starting at 21 days after MCAO. An array of behavioral tests was performed up to120 days after MCAO. Results Ischemic rats treated with RPh201 exhibited significant (p < 0.05) improvement of neurological function measured by adhesive removal test, foot-fault test, and modified neurological severity score at 90 and 120 days after MCAO. Immunohistochemistry analysis showed that RPh201 treatment robustly increased neurofilament heavy chain positive axons and myelin basic protein densities in the peri-infarct area by 61% and 31%, respectively, when compared to the Vehicle treatment, which were further confirmed by Western blot analysis. The RPh201 treatment did not reduce infarct volume. Conclusion Our data demonstrated that RPh201 has a therapeutic effect on improvement of functional recovery in male ischemic rats even when the treatment was initiated 21 days post stroke. Enhanced axonal and myelination densities by RPh201 in ischemic brain may contribute to improved stroke recovery.
Collapse
Affiliation(s)
- Chunyang Wang
- Department of Neurology, Henry Ford Hospital, Detroit, MI, United States
| | - Michael Chopp
- Department of Neurology, Henry Ford Hospital, Detroit, MI, United States.,Department of Physics, Oakland University, Rochester, MI, United States
| | - Rui Huang
- Department of Neurology, Henry Ford Hospital, Detroit, MI, United States
| | - Chao Li
- Department of Neurology, Henry Ford Hospital, Detroit, MI, United States
| | - Yi Zhang
- Department of Neurology, Henry Ford Hospital, Detroit, MI, United States
| | | | - Mei Lu
- Department of Biostatistics and Research Epidemiology, Henry Ford Hospital, Detroit, MI, United States
| | | | - Zheng Gang Zhang
- Department of Neurology, Henry Ford Hospital, Detroit, MI, United States
| | - Li Zhang
- Department of Neurology, Henry Ford Hospital, Detroit, MI, United States
| |
Collapse
|
14
|
Li L, Li R, Zacharek A, Wang F, Landschoot-Ward J, Chopp M, Chen J, Cui X. ABCA1/ApoE/HDL Signaling Pathway Facilitates Myelination and Oligodendrogenesis after Stroke. Int J Mol Sci 2020; 21:ijms21124369. [PMID: 32575457 PMCID: PMC7352241 DOI: 10.3390/ijms21124369] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 06/15/2020] [Accepted: 06/16/2020] [Indexed: 02/07/2023] Open
Abstract
ATP-binding cassette transporter A1 (ABCA1) plays an important role in the regulation of apolipoprotein E (ApoE) and the biogenesis of high-density lipoprotein (HDL) cholesterol in the mammalian brain. Cholesterol is a major source for myelination. Here, we investigate whether ABCA1/ApoE/HDL contribute to myelin repair and oligodendrogenesis in the ischemic brain after stroke. Specific brain ABCA1-deficient (ABCA1-B/-B) and ABCA1-floxed (ABCA1fl/fl) control mice were subjected to permanent distal middle-cerebral-artery occlusion (dMCAo) and were intracerebrally administered (1) artificial mouse cerebrospinal fluid (CSF) as vehicle control, (2) human plasma HDL3, and (3) recombined human ApoE2 starting 24 h after dMCAo for 14 days. All stroke mice were sacrificed 21 days after dMCAo. The ABCA1-B/-B–dMCAo mice exhibit significantly reduced myelination and oligodendrogenesis in the ischemic brain as well as decreased functional outcome 21 days after stroke compared with ABCA1fl/fl mice; administration of human ApoE2 or HDL3 in the ischemic brain significantly attenuates the deficits in myelination and oligodendrogenesis in ABCA1-B/-B–dMCAo mice ( p < 0.05, n = 9/group). In vitro, ABCA1-B/-B reduces ApoE expression and decreases primary oligodendrocyte progenitor cell (OPC) migration and oligodendrocyte maturation; HDL3 and ApoE2 treatment significantly reverses ABCA1-B/-B-induced reduction in OPC migration and oligodendrocyte maturation. Our data indicate that the ABCA1/ApoE/HDL signaling pathway contributes to myelination and oligodendrogenesis in the ischemic brain after stroke.
Collapse
Affiliation(s)
- Li Li
- Department of Neurology, Henry Ford Hospital, Detroit, MI 48202, USA; (L.L.); (R.L.); (A.Z.); (F.W.); (J.L.-W.); (M.C.); (J.C.)
| | - Rongwen Li
- Department of Neurology, Henry Ford Hospital, Detroit, MI 48202, USA; (L.L.); (R.L.); (A.Z.); (F.W.); (J.L.-W.); (M.C.); (J.C.)
| | - Alex Zacharek
- Department of Neurology, Henry Ford Hospital, Detroit, MI 48202, USA; (L.L.); (R.L.); (A.Z.); (F.W.); (J.L.-W.); (M.C.); (J.C.)
| | - Fengjie Wang
- Department of Neurology, Henry Ford Hospital, Detroit, MI 48202, USA; (L.L.); (R.L.); (A.Z.); (F.W.); (J.L.-W.); (M.C.); (J.C.)
| | - Julie Landschoot-Ward
- Department of Neurology, Henry Ford Hospital, Detroit, MI 48202, USA; (L.L.); (R.L.); (A.Z.); (F.W.); (J.L.-W.); (M.C.); (J.C.)
| | - Michael Chopp
- Department of Neurology, Henry Ford Hospital, Detroit, MI 48202, USA; (L.L.); (R.L.); (A.Z.); (F.W.); (J.L.-W.); (M.C.); (J.C.)
- Department of Physics, Oakland University, Rochester, MI 48309, USA
| | - Jieli Chen
- Department of Neurology, Henry Ford Hospital, Detroit, MI 48202, USA; (L.L.); (R.L.); (A.Z.); (F.W.); (J.L.-W.); (M.C.); (J.C.)
| | - Xu Cui
- Department of Neurology, Henry Ford Hospital, Detroit, MI 48202, USA; (L.L.); (R.L.); (A.Z.); (F.W.); (J.L.-W.); (M.C.); (J.C.)
- Correspondence: ; Tel.: 01-313-916-2864
| |
Collapse
|
15
|
Tamoxifen promotes white matter recovery and cognitive functions in male mice after chronic hypoperfusion. Neurochem Int 2019; 131:104566. [PMID: 31593788 DOI: 10.1016/j.neuint.2019.104566] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 09/30/2019] [Accepted: 10/02/2019] [Indexed: 12/18/2022]
Abstract
Cerebral white matter lesions (WMLs) induced by chronic cerebral hypoperfusion are one of the major components of stroke pathology and closely associated with cognitive impairment. However, the repair and related pathophysiology of white matter after brain injury remains relatively elusive and underexplored. Successful neuroregeneration is a method for the potential treatment of central nervous system (CNS) disorders. A non-steroidal estrogen receptor modulator, Tamoxifen, is an effective inhibitor of cell-swelling-activated anion channels and can mimic neuroprotective effects of estrogen in experimental ischemic stroke. However, its remains unclear whether Tamoxifen has beneficial effects in the pathological process after WMLs. In the present study, we investigated the efficacy of Tamoxifen on multiple elements of oligovascular niche of the male C57BL/6 mice brain after bilateral carotid artery stenosis (BCAS) - induced WMLs. Tamoxifen was injected intraperitoneally once daily from 1 day after BCAS until 1 day before sacrificed. Following chronic hypoperfusion, BCAS mice presented white matter demyelination, loss of axon-glia integrity, activated inflammatory response, and cognitive impairments. Tamoxifen treatment significantly facilitated functional restoration of working memory impairment in mice after white matter injury, thus indicating a translational potential for this estrogen receptor modulator given its clinical safety and applicability for WMLs, which lack of currently available treatments. Furthermore, Tamoxifen treatment reduced microglia activation and inflammatory response, favored microglial polarization toward to the M2 phenotype, enhanced oligodendrocyte precursor cells proliferation and differentiation, and promoted remyelination after chronic hypoperfusion. Together, our data indicate that Tamoxifen could alleviate white matter injury and play multiple targets protective effects following chronic hypoperfusion, which is a promising candidate for the therapeutic target for ischemic WMLs and other demyelination diseases associated cognitive impairment.
Collapse
|
16
|
Histopathological characterization of Toxocara canis- and T. cati-induced neurotoxocarosis in the mouse model. Parasitol Res 2019; 118:2591-2600. [PMID: 31350619 DOI: 10.1007/s00436-019-06395-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 07/05/2019] [Indexed: 12/30/2022]
Abstract
Infective larvae of Toxocara canis and T. cati, the common roundworms of dogs and cats, may invade the central nervous system of paratenic hosts, including humans, causing neurotoxocarosis (NT). Previous studies on NT in the model organism "mouse" have indicated distinct differences between T. canis and T. cati regarding larval migration patterns as well as the severity of clinical symptoms and behavioural alterations. The objective of the present study was to provide an extensive characterization of the underlying histopathological alterations, comparing T. canis- and T. cati-induced changes in different brain areas over the course of murine infection. Four histological sections of five brains each of T. canis- and T. cati-infected as well as uninfected C57Bl/6 mice were investigated 7, 14, 28, 42, 70 and 98 days post infection (dpi), while brains of T. cati-infected and control mice were also available 120 and 150 dpi. In addition to haematoxylin-eosin and luxol fast blue-cresyl violet staining, immunohistochemistry was employed to study microglia/macrophage cell morphology and to detect accumulation of β-amyloid precursor protein (β-APP) as an indicator of axonal damage. Haemorrhages, eosinophilic vasculitis and activated microglia/macrophages were detected in both infection groups starting 7 dpi, followed by eosinophilic meningitis in cerebra as from 14 dpi. Overall, little differences in the proportion of animals affected by these alterations were found between the two infection groups. In contrast, the proportion of animals displaying β-APP accumulation was significantly higher in the T. canis than T. cati group as from 28 dpi regarding the cerebrum as well as at 98 dpi regarding the cerebellum. In T. canis-infected mice, myelinophagic microglia/macrophages ("gitter cells") appeared as from 14 dpi, whereas these were first observed at 70 dpi in T. cati-infected animals. The proportion of animals displaying demyelination and/or gitter cells in the cerebrum was significantly higher in the T. canis than T. cati group as from 28 dpi, and at 28 and 42 dpi regarding the cerebellum. Earlier and more severe neurodegeneration during T. canis- than T. cati-induced NT, especially in the cerebrum, may explain the differences in behavioural alterations observed in previous studies. In addition to differences in larval migration preferences, immunological processes may contribute to these patterns, which warrant further investigation.
Collapse
|
17
|
Liu LQ, Liu XR, Zhao JY, Yan F, Wang RL, Wen SH, Wang L, Luo YM, Ji XM. Brain-selective mild hypothermia promotes long-term white matter integrity after ischemic stroke in mice. CNS Neurosci Ther 2018; 24:1275-1285. [PMID: 30295998 DOI: 10.1111/cns.13061] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 08/16/2018] [Accepted: 08/18/2018] [Indexed: 12/17/2022] Open
Abstract
INTRODUCTION The neuroprotective effects of hypothermia in acute ischemic stroke are well documented. However, the mechanisms involved in the effects remain to be clearly elucidated and the role of hypothermia on long-term white matter integrity after acute ischemic stroke has yet to be investigated. AIMS To investigate the role of mild focal hypothermia on long-term white matter (WM) integrity after transient cerebral ischemia. RESULTS Mild focal hypothermia treatment immediately after ischemic stroke significantly promotes WM integrity 28 days after the occlusion of the middle cerebral artery (MCAO) in mice. Higher integrity of white matter, lower activation of total microglia, less infarct volume, and better neurobehavioral function were detected in hypothermia-treated mice compared to normothermia-treated mice. Furthermore, we found that hypothermia could decrease detrimental M1 phenotype microglia and promote healthy M2 phenotype microglia. In vitro, results also indicated that hypothermia promoted oligodendrocytes differentiation and maturation after oxygen glucose deprivation. CONCLUSION Hypothermia promotes long-term WM integrity and inhibits neuroinflammation in a mouse model of ischemic brain injury.
Collapse
Affiliation(s)
- Li-Qiang Liu
- Cerebrovascular Disease Research Institute, Xuanwu Hospital, Capital Medical University, Beijing, China.,Stroke Center, Beijing Institute for Brain Disorders, Beijing, China.,Beijing Key Laboratory of Hypoxia Conditioning Translational Medicine, Beijing, China.,Department of Neurology, Inner Mongolia Baogang Hospital, Baotou, Inner Mongolia, China
| | - Xiang-Rong Liu
- Cerebrovascular Disease Research Institute, Xuanwu Hospital, Capital Medical University, Beijing, China.,China-America Joint Institute of Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Jing-Yan Zhao
- Stroke Center, Beijing Institute for Brain Disorders, Beijing, China.,China-America Joint Institute of Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing, China.,Pittsburgh Institute of Brain Disorders & Recovery and Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Feng Yan
- Cerebrovascular Disease Research Institute, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Rong-Liang Wang
- Cerebrovascular Disease Research Institute, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Shao-Hong Wen
- Cerebrovascular Disease Research Institute, Xuanwu Hospital, Capital Medical University, Beijing, China.,China-America Joint Institute of Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Lei Wang
- Cerebrovascular Disease Research Institute, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Yu-Min Luo
- Cerebrovascular Disease Research Institute, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Xun-Ming Ji
- Cerebrovascular Disease Research Institute, Xuanwu Hospital, Capital Medical University, Beijing, China.,Stroke Center, Beijing Institute for Brain Disorders, Beijing, China.,Beijing Key Laboratory of Hypoxia Conditioning Translational Medicine, Beijing, China.,Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
| |
Collapse
|
18
|
Michalski D, Keck AL, Grosche J, Martens H, Härtig W. Immunosignals of Oligodendrocyte Markers and Myelin-Associated Proteins Are Critically Affected after Experimental Stroke in Wild-Type and Alzheimer Modeling Mice of Different Ages. Front Cell Neurosci 2018; 12:23. [PMID: 29467621 PMCID: PMC5807905 DOI: 10.3389/fncel.2018.00023] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Accepted: 01/15/2018] [Indexed: 12/31/2022] Open
Abstract
Because stroke therapies are still limited and patients are often concerned by long-term sequelae with significant impairment of daily living, elaborated neuroprotective strategies are needed. During the last decades, research substantially improved the knowledge on cellular pathologies responsible for stroke-related tissue damage. In this context, the neurovascular unit (NVU) concept has been established, summarizing the affections of neurons, associated astrocytes and the vasculature. Although oligodendrocytes were already identified to play a major role in other brain pathologies, their role during stroke evolution and long-lasting tissue damage is poorly understood. This study aims to explore oligodendrocyte structures, i.e., oligodendrocytes and their myelin-associated proteins, after experimental focal cerebral ischemia. For translational issues, different ages and genotypes including an Alzheimer-like background were considered to mimic potential co-morbidities. Three- and 12-month-old wild-type and triple-transgenic mice were subjected to unilateral middle cerebral artery occlusion. Immunofluorescence labeling was performed on forebrain tissues affected by 24 h of ischemia to visualize the oligodendrocyte-specific protein (OSP), the myelin basic protein (MBP), and the neuron-glia antigen 2 (NG2) with reference to the ischemic lesion. Subsequent analyses concomitantly detected the vasculature and the 2′, 3′-cyclic nucleotide-3′-phosphodiesterase (CNPase) to consider the NVU concept and to explore the functional relevance of histochemical data on applied oligodendrocyte markers. While the immunosignal of NG2 was found to be nearly absent 24 h after ischemia onset, enhanced immunoreactivities for OSP and especially MBP were observed in close regional association to the vasculature. Added quantitative analyses based on inter-hemispheric differences of MBP-immunoreactivity revealed a shell-like pattern with a significant increase directly in the ischemic core, followed by a gradual decline toward the striatum, the ischemic border zone and the lateral neocortex. This observation was consistent in subsequent analyses on the potential impact of age and genetic background. Furthermore, immunoreactivities for CNPase, MBP, and OSP were found to be simultaneously enhanced. In conclusion, this study provides evidence for a critical role of oligodendrocyte structures in the early phase after experimental stroke, strengthening their involvement in the ischemia-affected NVU. Consequently, oligodendrocytes and their myelin-associated proteins may qualify as potential targets for neuroprotective and regenerative approaches in stroke.
Collapse
Affiliation(s)
| | - Anna L Keck
- Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| | | | | | - Wolfgang Härtig
- Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
| |
Collapse
|
19
|
Shin JA, Kim YA, Kim HW, Kim HS, Lee KE, Kang JL, Park EM. Iron released from reactive microglia by noggin improves myelin repair in the ischemic brain. Neuropharmacology 2018; 133:202-215. [PMID: 29407213 DOI: 10.1016/j.neuropharm.2018.01.038] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 01/21/2018] [Accepted: 01/25/2018] [Indexed: 12/31/2022]
Abstract
We previously reported that the bone morphogenetic protein (BMP) antagonist, noggin, improved the repair process with an increase in the reactive microglia/macrophage population in the ischemic brain. Since BMP plays a role in intracellular iron homeostasis via the hepcidin/ferroportin axis, and iron is required for myelination, this study was aimed to determine whether noggin affected iron status and remyelination in the brain following ischemic stroke. We further examined the effect of blocking the BMP/hepcidin pathway on reactive microglia (BV2) and myelination of oligodendroglial cells (MO3.13) to define the link between microglial iron status and myelin formation. Following the noggin infusion into the ischemic brain of mice, the induction of hepcidin and ferritin protein levels decreased, and the number of myelinated axons and myelin thickness increased at 8 weeks after ischemic stroke. Noggin repressed the increase in hepcidin and ferritin levels in BV2 exposed to lipopolysaccharide (LPS) and oxygen/glucose deprivation and reperfusion (OGD/R). When MO3.13 were exposed to the conditioned media from noggin-treated BV2 (noggin CM) during reperfusion, OGD/R-induced MO3.13 cell death was reduced. Under normal conditions, noggin CM induced myelin production with an increase in ferritin levels in MO3.13, which was reversed by the iron chelator, deferoxamine. These results indicated that noggin altered the iron status in reactive microglia from the iron-storing to the iron-releasing phenotype, which contributed to myelin synthesis by providing iron. We suggest that the BMP/hepcidin pathway can be a target for the regulation of the iron status in microglia to enhance remyelination in the ischemic brain.
Collapse
Affiliation(s)
- Jin A Shin
- Department of Pharmacology, College of Medicine, Ewha Womans University, Seoul, 07985, Republic of Korea; Tissue Injury Defense Research Center, College of Medicine, Ewha Womans University, Seoul, 07985, Republic of Korea
| | - Yul A Kim
- Department of Pharmacology, College of Medicine, Ewha Womans University, Seoul, 07985, Republic of Korea
| | - Hye Won Kim
- Department of Pharmacology, College of Medicine, Ewha Womans University, Seoul, 07985, Republic of Korea; Tissue Injury Defense Research Center, College of Medicine, Ewha Womans University, Seoul, 07985, Republic of Korea
| | - Hee-Sun Kim
- Tissue Injury Defense Research Center, College of Medicine, Ewha Womans University, Seoul, 07985, Republic of Korea; Department of Molecular Medicine, College of Medicine, Ewha Womans University, Seoul, 07985, Republic of Korea
| | - Kyung-Eun Lee
- Department of Pharmacology, College of Medicine, Ewha Womans University, Seoul, 07985, Republic of Korea
| | - Jihee Lee Kang
- Tissue Injury Defense Research Center, College of Medicine, Ewha Womans University, Seoul, 07985, Republic of Korea; Department of Physiology, College of Medicine, Ewha Womans University, Seoul, 07985, Republic of Korea
| | - Eun-Mi Park
- Department of Pharmacology, College of Medicine, Ewha Womans University, Seoul, 07985, Republic of Korea; Tissue Injury Defense Research Center, College of Medicine, Ewha Womans University, Seoul, 07985, Republic of Korea.
| |
Collapse
|
20
|
Soluble epoxide hydrolase inhibition Promotes White Matter Integrity and Long-Term Functional Recovery after chronic hypoperfusion in mice. Sci Rep 2017; 7:7758. [PMID: 28798352 PMCID: PMC5552839 DOI: 10.1038/s41598-017-08227-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 07/06/2017] [Indexed: 11/08/2022] Open
Abstract
Chronic cerebral hypoperfusion induced cerebrovascular white matter lesions (WMLs) are closely associated with cognitive impairment and other neurological deficits. The mechanism of demyelination in response to hypoperfusion has not yet been fully clarified. Soluble epoxide hydrolase (sEH) is an endogenous key enzyme in the metabolic conversion and degradation of P450 eicosanoids called epoxyeicosatrienoic acids. Inhibition of sEH has been suggested to represent a prototype "combination therapy" targeting multiple mechanisms of stroke injury with a single agent. However, its role in the pathological process after WMLs has not been clarified. The present study was to investigate the role of a potent sEH inhibitor, 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl) urea (TPPU), on multiple elements in white matter of mice brain after chronic hypoperfusion. Adult male C57BL/6 mice were subjected to bilateral carotid artery stenosis (BCAS) to induce WMLs. Administration of TPPU significantly inhibited microglia activation and inflammatory response, increased M2 polarization of microglial cells, enhanced oligodendrogenesis and differentiation of oligodendrocytes, promoted white matter integrity and remyelination following chronic hypoperfusion. Moreover, these cellular changes were translated into a remarkable functional restoration. The results suggest that sEH inhibition could exert multi-target protective effects and alleviate cognitive impairment after chronic hypoperfusion induced WMLs in mice.
Collapse
|
21
|
Yates NJ, Lydiard S, Fehily B, Weir G, Chin A, Bartlett CA, Alderson J, Fitzgerald M. Repeated mild traumatic brain injury in female rats increases lipid peroxidation in neurons. Exp Brain Res 2017; 235:2133-2149. [PMID: 28417146 DOI: 10.1007/s00221-017-4958-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 04/07/2017] [Indexed: 11/30/2022]
Abstract
Negative outcomes of mild traumatic brain injury (mTBI) can be exacerbated by repeated insult. Animal models of repeated closed-head mTBI provide the opportunity to define acute pathological mechanisms as the number of mTBI increases. Furthermore, little is known about the effects of mTBI impact site, and how this may affect brain function. We use a closed head, weight drop model of mTBI that allows head movement following impact, in adult female rats to determine the role of the number and location of mTBI on brain pathology and behaviour. Biomechanical assessment of two anatomically well-defined mTBI impact sites were used, anterior (bregma) and posterior (lambda). Location of the impact had no significant effect on impact forces (450 N), and the weight impact locations were on average 5.4 mm from the desired impact site. No between location vertical linear head kinematic differences were observed immediately following impact, however, in the 300 ms post-impact, significantly higher mean vertical head displacement and velocity were observed in the mTBI lambda trials. Breaches of the blood brain barrier were observed with three mTBI over bregma, associated with immunohistochemical indicators of damage. However, an increased incidence of hairline fractures of the skull and macroscopic haemorrhaging made bregma an unsuitable impact location to model repeated mTBI. Repeated mTBI over lambda did not cause skull fractures and were examined more comprehensively, with outcomes following one, two or three mTBI or sham, delivered at 1 day intervals, assessed on days 1-4. We observe a mild behavioural phenotype, with subtle deficits in cognitive function, associated with no identifiable neuroanatomical or inflammatory changes. However, an increase in lipid peroxidation in a subset of cortical neurons following two mTBI indicates increasing oxidative damage with repeated injury in female rats, supported by increased amyloid precursor protein immunoreactivity with three mTBI. This study of acute events following closed head mTBI identifies lipid peroxidation in neurons at the same time as cognitive deficits. Our study adds to existing literature, providing biomechanics data and demonstrating mild cognitive disturbances associated with diffuse injury, predominantly to grey matter, acutely following repeated mTBI.
Collapse
Affiliation(s)
- Nathanael J Yates
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Perth, Australia
| | - Stephen Lydiard
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Perth, Australia
| | - Brooke Fehily
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Perth, Australia
| | - Gillian Weir
- School of Sport Science, Exercise and Health, The University of Western Australia, Perth, WA, 6009, Australia
| | - Aaron Chin
- School of Sport Science, Exercise and Health, The University of Western Australia, Perth, WA, 6009, Australia
| | - Carole A Bartlett
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Perth, Australia
| | - Jacqueline Alderson
- School of Sport Science, Exercise and Health, The University of Western Australia, Perth, WA, 6009, Australia.,Auckland University of Technology, Sports Performance Research Institute New Zealand (SPRINZ), Auckland, New Zealand
| | - Melinda Fitzgerald
- Experimental and Regenerative Neurosciences, School of Biological Sciences, The University of Western Australia, Perth, Australia. .,Curtin Health Innovation Research Institute, Curtin University, Bentley, Australia. .,Perron Institute for Nerurological and Translational Science, Sarich Neuroscience Research Institute, Verdun St, Nedlands, WA, 6009, Australia.
| |
Collapse
|
22
|
Li Y, Gao X, Wang Q, Yang Y, Liu H, Zhang B, Li L. Retinoic acid protects from experimental cerebral infarction by upregulating GAP-43 expression. ACTA ACUST UNITED AC 2017; 50:e5561. [PMID: 28380213 PMCID: PMC5423748 DOI: 10.1590/1414-431x20175561] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 01/16/2017] [Indexed: 01/31/2023]
Abstract
The aim of this study was to investigate whether exogenous retinoic acid (RA) can upregulate the mRNA and protein expression of growth-associated protein 43 (GAP-43), thereby promoting brain functional recovery in a rat distal middle cerebral artery occlusion (MCAO) model of ischemia. A total of 216 male Sprague Dawley rats weighing 300–320 g were divided into 3 groups: sham-operated group, MCAO+vehicle group and MCAO+RA group. Focal cortical infarction was induced with a distal MCAO model. The expression of GAP-43 mRNA and protein in the ipsilateral perifocal region was assessed using qPCR and immunocytochemistry at 1, 3, 7, 14, 21, and 28 days after distal MCAO. In addition, an intraperitoneal injection of RA was given 12 h before MCAO and continued every day until the animal was sacrificed. Following ischemia, the expression of GAP-43 first increased considerably and then decreased. Administration of RA reduced infarction volume, promoted neurological functional recovery and upregulated expression of GAP-43. Administration of RA can ameliorate neuronal damage and promote nerve regeneration by upregulating the expression of GAP-43 in the perifocal region after distal MCAO.
Collapse
Affiliation(s)
- Y Li
- Department of Geriatrics, Southern Medical University Zhu Jiang Hospital, Guangzhou, China
| | - X Gao
- Department of Neurology, Southern Medical University Zhu Jiang Hospital, Guangzhou, China
| | - Q Wang
- Department of Neurology, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Y Yang
- Department of Geriatrics, Southern Medical University Zhu Jiang Hospital, Guangzhou, China
| | - H Liu
- Department of Geriatrics, Southern Medical University Zhu Jiang Hospital, Guangzhou, China
| | - B Zhang
- The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - L Li
- Department of Neurology, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China
| |
Collapse
|
23
|
|
24
|
Marucci G, Dal Ben D, Lambertucci C, Santinelli C, Spinaci A, Thomas A, Volpini R, Buccioni M. The G Protein-Coupled Receptor GPR17: Overview and Update. ChemMedChem 2016; 11:2567-2574. [PMID: 27863043 DOI: 10.1002/cmdc.201600453] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 10/17/2016] [Indexed: 11/08/2022]
Abstract
The GPR17 receptor is a G protein-coupled receptor (GPCR) that seems to respond to two unrelated families of endogenous ligands: nucleotide sugars (UDP, UDP-galactose, and UDP-glucose) and cysteinyl leukotrienes (LTD4 , LTC4 , and LTE4 ), with significant affinity at micromolar and nanomolar concentrations, respectively. This receptor has a broad distribution at the level of the central nervous system (CNS) and is found in neurons and in a subset of oligodendrocyte precursor cells (OPCs). Unfortunately, disparate results emerging from different laboratories have resulted in a lack of clarity with regard to the role of GPR17-targeting ligands in OPC differentiation and in myelination. GPR17 is also highly expressed in organs typically undergoing ischemic damage and has various roles in specific phases of adaptations that follow a stroke. Under such conditions, GPR17 plays a crucial role; in fact, its inhibition decreases the progression of ischemic damage. This review summarizes some important features of this receptor that could be a novel therapeutic target for the treatment of demyelinating diseases and for repairing traumatic injury.
Collapse
Affiliation(s)
- Gabriella Marucci
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, Via S. Agostino, 1, 62032, Camerino, MC, Italy
| | - Diego Dal Ben
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, Via S. Agostino, 1, 62032, Camerino, MC, Italy
| | - Catia Lambertucci
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, Via S. Agostino, 1, 62032, Camerino, MC, Italy
| | - Claudia Santinelli
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, Via S. Agostino, 1, 62032, Camerino, MC, Italy
| | - Andrea Spinaci
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, Via S. Agostino, 1, 62032, Camerino, MC, Italy
| | - Ajiroghene Thomas
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, Via S. Agostino, 1, 62032, Camerino, MC, Italy
| | - Rosaria Volpini
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, Via S. Agostino, 1, 62032, Camerino, MC, Italy
| | - Michela Buccioni
- School of Pharmacy, Medicinal Chemistry Unit, University of Camerino, Via S. Agostino, 1, 62032, Camerino, MC, Italy
| |
Collapse
|
25
|
Castejón OJ. Ultrastructural Pathology of Oligodendroglial Cells in Traumatic and Hydrocephalic Human Brain Edema: A Review. Ultrastruct Pathol 2016; 39:359-68. [PMID: 26548433 DOI: 10.3109/01913123.2012.750408] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Oligodendroglial cell changes in human traumatic brain injuries and hydrocephalus have been reviewed and compared with experimental brain edema. Resting unreactive oligodendrocytes, reactive oligodendrocytes, anoxic-ischemic oligodendrocytes, hyperthrophic phagocytic oligodendrocytes, and apoptotic oligodendrocytes are found. Anoxic-ischemic oligodendrocytes exhibit enlargement of endoplasmic reticulum, Golgi complex, and enlargement and disassembly of nuclear envelope. They appear in contact with degenerated myelinated axons. Hypertrophic phagocytic oligodendrocytes engulf degenerated myelinated axons exerting myelinolytic effects. A continuum oncotic and apoptotic cell death type leading to necrosis is observed. The vasogenic and cytotoxic components of brain edema are discussed in relation to oligodendroglial cell changes and reactivity.
Collapse
Affiliation(s)
- Orlando J Castejón
- a Biological Research Institute "Drs. Orlando Castejón and Haydée Viloria de Castejón," School of Medicine, Universidad del Zulia , Maracaibo , Venezuela
| |
Collapse
|
26
|
Zhang Z, Chopp M. Neural Stem Cells and Ischemic Brain. J Stroke 2016; 18:267-272. [PMID: 27488979 PMCID: PMC5066435 DOI: 10.5853/jos.2016.00206] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 05/13/2016] [Accepted: 05/18/2016] [Indexed: 01/19/2023] Open
Abstract
Stroke activates neural stem cells in the ventricular-subventricular zone (V/SVZ) of the lateral ventricle, which increases neuroblasts and oligodendrocyte progenitor cells (OPCs). Within the ischemic brain, neural stem cells, neuroblasts and OPCs appear to actively communicate with cerebral endothelial cells and other brain parenchymal cells to mediate ischemic brain repair; however, stroke-induced neurogenesis unlikely plays any significant roles in neuronal replacement. In this mini-review, we will discuss recent findings how intercellular communications between stroke-induced neurogenesis and oligodendrogenesis and brain parenchymal cells could potentially facilitate brain repair processes.
Collapse
Affiliation(s)
| | - Michael Chopp
- Henry Ford Hospital, Michigan, United States.,Department of Physics, Oakland University, Rochester, Michigan, United States
| |
Collapse
|
27
|
Abstract
Stroke is one of the leading causes of death and disability worldwide. Stroke recovery is orchestrated by a set of highly interactive processes that involve the neurovascular unit and neural stem cells. Emerging data suggest that exosomes play an important role in intercellular communication by transferring exosomal protein and RNA cargo between source and target cells in the brain. Here, we review these advances and their impact on promoting coupled brain remodeling processes after stroke. The use of exosomes for therapeutic applications in stroke is also highlighted.
Collapse
Affiliation(s)
- Zheng Gang Zhang
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, USA
| | - Michael Chopp
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, USA
- Department of Physics, Oakland University, Rochester, Michigan, USA
| |
Collapse
|
28
|
Hunt NJ, Phillips L, Waters KA, Machaalani R. Proteomic MALDI-TOF/TOF-IMS examination of peptide expression in the formalin fixed brainstem and changes in sudden infant death syndrome infants. J Proteomics 2016; 138:48-60. [PMID: 26926438 DOI: 10.1016/j.jprot.2016.02.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 01/30/2016] [Accepted: 02/23/2016] [Indexed: 01/23/2023]
Abstract
UNLABELLED Matrix assisted laser desorption/ionisation imaging mass spectrometry (MALDI-IMS) has not previously been utilised to examine sudden infant death syndrome (SIDS). This study aimed to optimise MALDI IMS for use on archived formalin-fixed-paraffin-embedded human infant medulla tissue (n=6, controls; n=6, SIDS) to evaluate differences between multiple nuclei of the medulla by using high resolution IMS. Profiles were compared between SIDS and age/sex matched controls. LC-MALDI identified 55 proteins based on 321 peptides across all samples; 286 peaks were found using IMS, corresponding to these 55 proteins that were directly compared between controls and SIDS. Control samples were used to identify common peptides for neuronal/non-neuronal structures allowing identification of medullary regions. In SIDS, abnormal expression patterns of 41 peptides (p≤0.05) corresponding to 9 proteins were observed; these changes were confirmed with immunohistochemistry. The protein abnormalities varied amongst nuclei, with the majority of variations in the raphe nuclei, hypoglossal and pyramids. The abnormal proteins are not related to a previously identified neurological disease pathway but consist of developmental neuronal/glial/axonal growth, cell metabolism, cyto-architecture and apoptosis components. This suggests that SIDS infants have abnormal neurological development in the raphe nuclei, hypoglossal and pyramids of the brainstem, which may contribute to the pathogenesis of SIDS. BIOLOGICAL SIGNIFICANCE This study is the first to perform an imaging mass spectrometry investigation in the human brainstem and also within sudden infant death syndrome (SIDS). LC MALDI and MALDI IMS identified 55 proteins based on 285 peptides in both control and SIDS tissue; with abnormal expression patterns present for 41/285 and 9/55 proteins in SIDS using IMS. The abnormal proteins are critical for neurological development; with the impairment supporting the hypothesis that SIDS may be due to delayed neurological maturation. The brainstem regions mostly affected included the raphe nuclei, hypoglossal and pyramids. This study highlights that basic cyto-architectural proteins are affected in SIDS and that abnormal expression of these proteins in other CNS disorders should be examined. KEY SENTENCES LC MALDI and MALDI IMS identified 55 proteins based on 285 peptides in both control and SIDS tissue. Abnormal expression patterns were present for 41/285 and 9/55 proteins in SIDS using IMS. Brainstem regions mostly affected included the raphe nuclei, hypoglossal and pyramids.
Collapse
Affiliation(s)
- Nicholas J Hunt
- Department of Medicine, Central Clinical School, University of Sydney, NSW, Australia; BOSCH Institute of Biomedical Research, University of Sydney, NSW, Australia
| | - Leo Phillips
- Hormones and Cancer Division, Kolling Institute of Medical Research, University of Sydney, Royal North Shore Hospital, NSW, Australia
| | - Karen A Waters
- Department of Medicine, Central Clinical School, University of Sydney, NSW, Australia; BOSCH Institute of Biomedical Research, University of Sydney, NSW, Australia; The Children's Hospital, Westmead, NSW 2145, Australia
| | - Rita Machaalani
- Department of Medicine, Central Clinical School, University of Sydney, NSW, Australia; BOSCH Institute of Biomedical Research, University of Sydney, NSW, Australia; The Children's Hospital, Westmead, NSW 2145, Australia.
| |
Collapse
|
29
|
Exercise Training Inhibits the Nogo-A/NgR1/Rho-A Signals in the Cortical Peri-infarct Area in Hypertensive Stroke Rats. Am J Phys Med Rehabil 2016; 94:1083-94. [PMID: 26135366 DOI: 10.1097/phm.0000000000000339] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The aim of this study was to test the hypothesis that exercise training promotes motor recovery after stroke by facilitating axonal remodeling via inhibition of the Nogo-A/NgR1 and Rho-A pathway. DESIGN A distal middle cerebral artery occlusion model was generated in stroke-prone renovascular hypertensive rats. Stroke-prone renovascular hypertensive rats were randomly divided into a control group, an exercise training group, and a sham group. Motor function was measured using the grip strength test. Axon and myelin remodeling markers, growth-associated protein 43, myelin basic protein, Tau, and amyloid precursor protein were detected by immunofluorescence. The expression of Nogo-A, NgR1, and Rho-A was demonstrated by immunofluorescence and Western blotting in the peri-infarction area at 7, 14, 28, and 52 days after distal middle cerebral artery occlusion. RESULTS Grip strength was higher in the exercise training group (P < 0.05). Exercise training increased the expression of growth-associated protein 43, myelin basic protein (at 7, 14, and 28 days), and Tau (at 7 and 14 days), and decreased the expression of axonal damage amyloid precursor protein (at 7 and 14 days), compared with the control group. The protein levels of Nogo-A (at 7 and 14 days), NgR1 (at 7, 14, and 28 days), and Rho-A (at 14 and 28 days) were reduced after exercise training. CONCLUSIONS Exercise training promotes axonal recovery, which is associated with functional improvement after cerebral infarction. Down-regulation of the Nogo-A/NgR1/Rho-A may mediate the axonal remodeling induced by exercise training.
Collapse
|
30
|
Astrocytes Promote Oligodendrogenesis after White Matter Damage via Brain-Derived Neurotrophic Factor. J Neurosci 2016; 35:14002-8. [PMID: 26468200 DOI: 10.1523/jneurosci.1592-15.2015] [Citation(s) in RCA: 169] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED Oligodendrocyte precursor cells (OPCs) in the adult brain contribute to white matter homeostasis. After white matter damage, OPCs compensate for oligodendrocyte loss by differentiating into mature oligodendrocytes. However, the underlying mechanisms remain to be fully defined. Here, we test the hypothesis that, during endogenous recovery from white matter ischemic injury, astrocytes support the maturation of OPCs by secreting brain-derived neurotrophic factor (BDNF). For in vitro experiments, cultured primary OPCs and astrocytes were prepared from postnatal day 2 rat cortex. When OPCs were subjected to chemical hypoxic stress by exposing them to sublethal CoCl2 for 7 d, in vitro OPC differentiation into oligodendrocytes was significantly suppressed. Conditioned medium from astrocytes (astro-medium) restored the process of OPC maturation even under the stressed conditions. When astro-medium was filtered with TrkB-Fc to remove BDNF, the BDNF-deficient astro-medium no longer supported OPC maturation. For in vivo experiments, we analyzed a transgenic mouse line (GFAP(cre)/BDNF(wt/fl)) in which BDNF expression is downregulated specifically in GFAP(+) astrocytes. Both wild-type (GFAP(wt)/BDNF(wt/fl) mice) and transgenic mice were subjected to prolonged cerebral hypoperfusion by bilateral common carotid artery stenosis. As expected, compared with wild-type mice, the transgenic mice exhibited a lower number of newly generated oligodendrocytes and larger white matter damage. Together, these findings demonstrate that, during endogenous recovery from white matter damage, astrocytes may promote oligodendrogenesis by secreting BDNF. SIGNIFICANCE STATEMENT The repair of white matter after brain injury and neurodegeneration remains a tremendous hurdle for a wide spectrum of CNS disorders. One potentially important opportunity may reside in the response of residual oligodendrocyte precursor cells (OPCs). OPCs may serve as a back-up for generating mature oligodendrocytes in damaged white matter. However, the underlying mechanisms are still mostly unknown. Here, we use a combination of cell biology and an animal model to report a new pathway in which astrocyte-derived BDNF supports oligodendrogenesis and regeneration after white matter damage. These findings provide new mechanistic insight into white matter physiology and pathophysiology, which would be broadly and clinically applicable to CNS disease.
Collapse
|
31
|
Cui X, Chopp M, Zacharek A, Cui C, Yan T, Ning R, Chen J. D-4F Decreases White Matter Damage After Stroke in Mice. Stroke 2015; 47:214-20. [PMID: 26604250 DOI: 10.1161/strokeaha.115.011046] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 10/27/2015] [Indexed: 01/10/2023]
Abstract
BACKGROUND AND PURPOSE Stroke-induced neuroinflammation and white matter damage are associated with neurological deficits. Whether D-4F, an apolipoprotein A-I mimetic peptide, treatment of stroke decreases neuroinflammation and white matter damage and improves functional outcome has not been investigated. METHODS Adult male C57BL/6 mice were subjected to permanent middle cerebral artery occlusion (MCAo) and were orally administered saline as a vehicle control and different doses of D-4F (2, 4, 8, 16, or 32 mg/kg) starting at 2 h after MCAo and daily until euthanized at 7 days after MCAo. D-4F treatment did not alter the blood levels of high-density lipoprotein, total cholesterol, triglyceride, blood-brain barrier leakage, and infarction volume compared with control group. RESULTS D-4F (16 mg/kg) treatment of stroke significantly improved functional outcome, increased the white matter density and the number of oligodendrocyte progenitor cells in the ischemic boundary zone of the ipsilateral striatum, and increased myelin basic protein, insulin-like growth factor-1 (IGF1), but decreased inflammatory factor Toll-like receptor-4 and tumor necrosis factor-α expression in the ischemic brain 7 days after MCAo (P<0.05, n=11/group). The neurite/axonal outgrowth in primary cultured neurons was significantly increased when treated with D-4F (100 ng/mL) and IGF1 (100 ng/mL) compared with the nontreatment control. Inhibition of IGF1 significantly attenuated D-4F or IGF1 treatment-induced axonal outgrowth. D-4F-treatment did not increase oligodendrocyte-progenitor cell proliferation but decreased oligodendrocyte-progenitor cell death. CONCLUSIONS D-4F treatment initiated 2 h after MCAo decreases neuroinflammation and white matter damage and improves functional outcome after stroke. D-4F-induced increase in IGF1 may contribute to D-4F-induced neurite/axonal outgrowth after stroke.
Collapse
Affiliation(s)
- Xu Cui
- From the Department of Neurology, Henry Ford Hospital, Detroit, MI (X.C., M.C., A.Z., C.C., T.Y., R.N., J.C.); and Department of Physics, Oakland University, Rochester, MI (M.C.)
| | - Michael Chopp
- From the Department of Neurology, Henry Ford Hospital, Detroit, MI (X.C., M.C., A.Z., C.C., T.Y., R.N., J.C.); and Department of Physics, Oakland University, Rochester, MI (M.C.)
| | - Alex Zacharek
- From the Department of Neurology, Henry Ford Hospital, Detroit, MI (X.C., M.C., A.Z., C.C., T.Y., R.N., J.C.); and Department of Physics, Oakland University, Rochester, MI (M.C.)
| | - Chengcheng Cui
- From the Department of Neurology, Henry Ford Hospital, Detroit, MI (X.C., M.C., A.Z., C.C., T.Y., R.N., J.C.); and Department of Physics, Oakland University, Rochester, MI (M.C.)
| | - Tao Yan
- From the Department of Neurology, Henry Ford Hospital, Detroit, MI (X.C., M.C., A.Z., C.C., T.Y., R.N., J.C.); and Department of Physics, Oakland University, Rochester, MI (M.C.)
| | - Ruizhuo Ning
- From the Department of Neurology, Henry Ford Hospital, Detroit, MI (X.C., M.C., A.Z., C.C., T.Y., R.N., J.C.); and Department of Physics, Oakland University, Rochester, MI (M.C.)
| | - Jieli Chen
- From the Department of Neurology, Henry Ford Hospital, Detroit, MI (X.C., M.C., A.Z., C.C., T.Y., R.N., J.C.); and Department of Physics, Oakland University, Rochester, MI (M.C.).
| |
Collapse
|
32
|
Itoh K, Maki T, Lok J, Arai K. Mechanisms of cell-cell interaction in oligodendrogenesis and remyelination after stroke. Brain Res 2015; 1623:135-49. [PMID: 25960351 PMCID: PMC4569526 DOI: 10.1016/j.brainres.2015.04.039] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 04/19/2015] [Accepted: 04/20/2015] [Indexed: 12/20/2022]
Abstract
White matter damage is a clinically important aspect of several central nervous system diseases, including stroke. Cerebral white matter primarily consists of axonal bundles ensheathed with myelin secreted by mature oligodendrocytes, which play an important role in neurotransmission between different areas of gray matter. During the acute phase of stroke, damage to oligodendrocytes leads to white matter dysfunction through the loss of myelin. On the contrary, during the chronic phase, white matter components promote an environment, which is favorable for neural repair, vascular remodeling, and remyelination. For effective remyelination to take place, oligodendrocyte precursor cells (OPCs) play critical roles by proliferating and differentiating into mature oligodendrocytes, which help to decrease the burden of axonal injury. Notably, other types of cells contribute to these OPC responses under the ischemic conditions. This mini-review summarizes the non-cell autonomous mechanisms in oligodendrogenesis and remyelination after white matter damage, focusing on how OPCs receive support from their neighboring cells. This article is part of a Special Issue entitled SI: Cell Interactions In Stroke.
Collapse
Affiliation(s)
- Kanako Itoh
- Neuroprotection Research Laboratory, Departments of Radiology and Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Takakuni Maki
- Neuroprotection Research Laboratory, Departments of Radiology and Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Josephine Lok
- Neuroprotection Research Laboratory, Departments of Radiology and Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA; Department of Pediatrics, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Ken Arai
- Neuroprotection Research Laboratory, Departments of Radiology and Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA.
| |
Collapse
|
33
|
Rosenzweig S, Carmichael ST. The axon-glia unit in white matter stroke: mechanisms of damage and recovery. Brain Res 2015; 1623:123-34. [PMID: 25704204 PMCID: PMC4545468 DOI: 10.1016/j.brainres.2015.02.019] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2015] [Accepted: 02/10/2015] [Indexed: 01/07/2023]
Abstract
Approximately one quarter of all strokes in humans occur in white matter, and the progressive nature of white matter lesions often results in severe physical and mental disability. Unlike cortical grey matter stroke, the pathology of white matter stroke revolves around disrupted connectivity and injured axons and glial cells, rather than neuronal cell bodies. Consequently, the mechanisms behind ischemic damage to white matter elements, the regenerative responses of glial cells and their signaling pathways, all differ significantly from those in grey matter. Development of effective therapies for white matter stroke would require an enhanced understanding of the complex cellular and molecular interactions within the white matter, leading to the identification of new therapeutic targets. This review will address the unique properties of the axon-glia unit during white matter stroke, describe the challenging process of promoting effective white matter repair, and discuss recently-identified signaling pathways which may hold potential targets for repair in this disease. This article is part of a Special Issue entitled SI: Cell Interactions In Stroke.
Collapse
Affiliation(s)
- Shira Rosenzweig
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
| | - S Thomas Carmichael
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
| |
Collapse
|
34
|
Zhang ZG, Chopp M. Promoting brain remodeling to aid in stroke recovery. Trends Mol Med 2015; 21:543-8. [PMID: 26278490 PMCID: PMC4567429 DOI: 10.1016/j.molmed.2015.07.005] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 07/17/2015] [Accepted: 07/17/2015] [Indexed: 12/13/2022]
Abstract
Endogenous brain repair after stroke involves a set of highly interactive processes, such as angiogenesis, neurogenesis, oligodendrogenesis, synaptogenesis, and axonal outgrowth, which together orchestrate neurological recovery. During the past several years, there have been advances in our understanding of miRNAs and histone deacetylases (HDACs) in brain repair processes after stroke. Emerging data indicate the important role of exosomes for intercellular communication in promoting coupled brain remodeling processes. These advances will likely have a major impact on the development of restorative therapies for ischemic brain repair, consequently leading to improvement of neurological function. In this review, we provide an update on our current understanding of cellular and molecular mechanisms of miRNAs, exosomes, and HDACs in brain restorative processes after stroke.
Collapse
Affiliation(s)
| | - Michael Chopp
- Department of Neurology, Henry Ford Hospital, Detroit, MI, USA; Department of Physics, Oakland University, Rochester, MI, USA
| |
Collapse
|
35
|
Neurotoxocarosis alters myelin protein gene transcription and expression. Parasitol Res 2015; 114:2175-86. [DOI: 10.1007/s00436-015-4407-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 03/02/2015] [Indexed: 02/04/2023]
|
36
|
Özen I, Deierborg T, Miharada K, Padel T, Englund E, Genové G, Paul G. Brain pericytes acquire a microglial phenotype after stroke. Acta Neuropathol 2014; 128:381-96. [PMID: 24848101 PMCID: PMC4131168 DOI: 10.1007/s00401-014-1295-x] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 05/14/2014] [Accepted: 05/14/2014] [Indexed: 11/28/2022]
Abstract
Pericytes are located on the abluminal side of endothelial cells lining the microvasculature in all organs. They have been identified as multipotent progenitor cells in several tissues of the body including the human brain. New evidence suggests that pericytes contribute to tissue repair, but their role in the injured brain is largely unknown. Here, we investigate the role of pericytes in ischemic stroke. Using a pericyte-reporter mouse model, we provide unique evidence that regulator of G-protein signaling 5 expressing cells are activated pericytes that leave the blood vessel wall, proliferate and give rise to microglial cells after ischemic brain injury. Consistently, we show that activated pericytes express microglial markers in human stroke brain tissue. We demonstrate that human brain-derived pericytes adopt a microglial phenotype and upregulate mRNA specific for activated microglial cells under hypoxic conditions in vitro. Our study indicates that the vasculature is a novel source of inflammatory cells with a microglial phenotype in brain ischemia and hence identifies pericytes as an important new target for the development of future stroke therapies.
Collapse
Affiliation(s)
- Ilknur Özen
- Translational Neurology Group, Department of Clinical Science, Wallenberg Neuroscience Center, Lund University, 22184 Lund, Sweden
| | - Tomas Deierborg
- Experimental Neuroinflammation Laboratory, Department of Experimental Medical Science, BMC, Lund University, 22184 Lund, Sweden
| | - Kenichi Miharada
- Department of Molecular Medicine and Gene Therapy, Lund Strategic Center for Stem Cell Biology and Cell Therapy, BMC, Lund University, 22184 Lund, Sweden
| | - Thomas Padel
- Translational Neurology Group, Department of Clinical Science, Wallenberg Neuroscience Center, Lund University, 22184 Lund, Sweden
| | - Elisabet Englund
- Department of Neuropathology, Scania University Hospital, 22185 Lund, Sweden
| | - Guillem Genové
- Division of Vascular Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institute, 17177 Stockholm, Sweden
| | - Gesine Paul
- Translational Neurology Group, Department of Clinical Science, Wallenberg Neuroscience Center, Lund University, 22184 Lund, Sweden
- Department of Neurology, Scania University Hospital, 22185 Lund, Sweden
| |
Collapse
|
37
|
Kassis H, Chopp M, Liu XS, Shehadah A, Roberts C, Zhang ZG. Histone deacetylase expression in white matter oligodendrocytes after stroke. Neurochem Int 2014; 77:17-23. [PMID: 24657831 DOI: 10.1016/j.neuint.2014.03.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 03/04/2014] [Accepted: 03/10/2014] [Indexed: 01/23/2023]
Abstract
Histone deacetylases (HDACs) constitute a super-family of enzymes grouped into four major classes (Class I-IV) that deacetylate histone tails leading to chromatin condensation and gene repression. Whether stroke-induced oligodendrogenesis is related to the expression of individual HDACs in the oligodendrocyte lineage has not been investigated. We found that 2 days after stroke, oligodendrocyte progenitor cells (OPCs) and mature oligodendrocytes (OLGs) were substantially reduced in the peri-infarct corpus callosum, whereas at 7 days after stroke, a robust increase in OPCs and OLGs was observed. Ischemic brains isolated from rats sacrificed 7 days after stroke were used to test levels of individual members of Class I (1 and 2) and Class II (4 and 5) HDACs in white matter oligodendrocytes during stroke-induced oligodendrogenesis. Double immunohistochemistry analysis revealed that stroke substantially increased the number of NG2+OPCs with nuclear HDAC1 and HDAC2 immunoreactivity and cytoplasmic HDAC4 which were associated with augmentation of proliferating OPCs, as determined by BrdU and Ki67 double reactive cells after stroke. A decrease in HDAC1 and an increase in HDAC2 immunoreactivity were detected in mature adenomatous polyposis coli (APC) positive OLGs, which paralleled an increase in newly generated BrdU positive OLGs in the peri-infarct corpus callosum. Concurrently, stroke substantially decreased the acetylation levels of histones H3 and H4 in both OPCs and OLGs. Taken together, these findings demonstrate that stroke induces distinct profiles of Class I and Class II HDACs in white matter OPCs and OLGs, suggesting that the individual members of Class I and II HDACs play divergent roles in the regulation of OPC proliferation and differentiation during brain repair after stroke.
Collapse
Affiliation(s)
- Haifa Kassis
- 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
| | - Xian Shuang Liu
- Department of Neurology, Henry Ford Health System, Detroit, MI 48202, USA
| | - Amjad Shehadah
- Department of Neurology, Henry Ford Health System, Detroit, MI 48202, USA
| | - Cynthia Roberts
- Department of Neurology, Henry Ford Health System, Detroit, MI 48202, USA
| | - Zheng Gang Zhang
- Department of Neurology, Henry Ford Health System, Detroit, MI 48202, USA.
| |
Collapse
|
38
|
Zhao L, Guo Y, Ji X, Zhang M. The neuroprotective effect of picroside II via regulating the expression of myelin basic protein after cerebral ischemia injury in rats. BMC Neurosci 2014; 15:25. [PMID: 24524292 PMCID: PMC3926676 DOI: 10.1186/1471-2202-15-25] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 02/11/2014] [Indexed: 12/17/2022] Open
Abstract
Background To explore the neuroprotective effect and optimize the therapeutic dose and time window of picroside II by orthogonal test and the expression of myelin basic protein (MBP) in cerebral ischemic injury in rats. Bilateral common carotid artery occlusion (BCCAO) was used to establish forebrain ischemia models. The successful rat models were grouped according to orthogonal experimental design and injected picroside II intraperitoneally at different ischemic time with different doses. Myelin sheath fast green staining(FGS) and transmission electron microscopy (TEM) were used to observe nerve fiber myelin; the expression of MBP was tested qualitatively and quantitatively by immunohistochemical assay (IHC) and Western blot (WB); Reverse transcription polymerase chain reaction (RT-PCR) was used to detect the transcription level of MBP mRNA. Results The protective effect of picroside II was presented by increasing the expression of MBP and decreasing demyelination after cerebral ischemic injury. The best therapeutic time window and dose was (1) ischemia 2.0 h with picroside II 10 mg/kg body weight according to the results of FGS, IHC and WB; (2) ischemia 1.5 h with picroside II 20 mg/kg according to the analysis of RT-PCR. Conclusion Given the principle of the longest time window and the lowest therapeutic dose, the optimized therapeutic dose and time window should be injecting picroside II intraperitoneally with 10-20 mg/kg body weight at ischemia 1.5-2.0 h in cerebral ischemic injury.
Collapse
Affiliation(s)
| | - Yunliang Guo
- Institute of Cerebrovascular Diseases, Affiliated Hospital of Qingdao University, Qingdao, Shandong 266003, China.
| | | | | |
Collapse
|
39
|
Oligogenesis and oligodendrocyte progenitor maturation vary in different brain regions and partially correlate with local angiogenesis after ischemic stroke. Transl Stroke Res 2013; 2:366-75. [PMID: 22022343 DOI: 10.1007/s12975-011-0078-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Oligogenesis plays an important role in functional recovery after ischemic stroke. We tested the hypothesis that oligogenesis and the maturation of oligodendrocyte progenitor cells (OPCs) vary in different brain regions using a rat transient middle cerebral artery occlusion (tMCAO) model. Compared to Day 1, olig2(+) OPCs and oligodendrocytes (OLGs) increased in the peri-infarct basal ganglia (BG) 7 (44%) and 14 (61%) days after 2 hours of MCAO; OPCs (PDGFRα(+)) and OLGs (CC1(+)) increased in this region 14 days after tMCAO by 139% and 126%, respectively. Although the olig2(+) cells and OLGs did not increase significantly in the peri-infarct cortex (CTX), the OPCs increased in this region by 95% at Day 14 vs. Day 1 after tMCAO. The numbers of OPCs and OLGs remained low after an initial reduction at Day 1 in the peri-infarct corpus callosum (CC). Correlation analyses showed that the numbers of olig2(+) cells (r=0.73, P=0.03) and OLGs (r=0.74, P=0.02) correlated with local vessel density; however, the number of OPCs did not correlate with vessel density (r=0.43, P=0.24). Our data show that oligogenesis and the maturation of OPCs differ in various brain regions and the difference in regional angiogenic response is one of the potential reasons.
Collapse
|
40
|
Zhang R, Chopp M, Zhang ZG. Oligodendrogenesis after cerebral ischemia. Front Cell Neurosci 2013; 7:201. [PMID: 24194700 PMCID: PMC3810592 DOI: 10.3389/fncel.2013.00201] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2013] [Accepted: 10/14/2013] [Indexed: 12/31/2022] Open
Abstract
Neural stem cells in the subventricular zone (SVZ) of the lateral ventricle of adult rodent brain generate oligodendrocyte progenitor cells (OPCs) that disperse throughout the corpus callosum and striatum where some of OPCs differentiate into mature oligodendrocytes. Studies in animal models of stroke demonstrate that cerebral ischemia induces oligodendrogenesis during brain repair processes. This article will review evidence of stroke-induced proliferation and differentiation of OPCs that are either resident in white matter or are derived from SVZ neural progenitor cells and of therapies that amplify endogenous oligodendrogenesis in ischemic brain.
Collapse
Affiliation(s)
- Ruilan Zhang
- Department of Neurology, Henry Ford Hospital Detroit, MI, USA
| | | | | |
Collapse
|
41
|
Ionic transporter activity in astrocytes, microglia, and oligodendrocytes during brain ischemia. J Cereb Blood Flow Metab 2013; 33:969-82. [PMID: 23549380 PMCID: PMC3705429 DOI: 10.1038/jcbfm.2013.44] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 02/27/2013] [Accepted: 02/28/2013] [Indexed: 01/09/2023]
Abstract
Glial cells constitute a large percentage of cells in the nervous system. During recent years, a large number of studies have critically attributed to glia a new role which no longer reflects the long-held view that glia constitute solely a silent and passive supportive scaffolding for brain cells. Indeed, it has been hypothesized that glia, partnering neurons, have a much more actively participating role in brain function. Alteration of intraglial ionic homeostasis in response to ischemic injury has a crucial role in inducing and maintaining glial responses in the ischemic brain. Therefore, glial transporters as potential candidates in stroke intervention are becoming promising targets to enhance an effective and additional therapy for brain ischemia. In this review, we will describe in detail the role played by ionic transporters in influencing astrocyte, microglia, and oligodendrocyte activity and the implications that these transporters have in the progression of ischemic lesion.
Collapse
|
42
|
Persson Å, Osman A, Bolouri H, Mallard C, Kuhn HG. Radixin expression in microglia after cortical stroke lesion. Glia 2013; 61:790-9. [PMID: 23440885 DOI: 10.1002/glia.22473] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 01/07/2013] [Indexed: 01/02/2023]
Abstract
Stroke induces extensive tissue remodeling, resulting in the activation of several cell types in the brain as well as recruitment of blood-borne leucocytes. Radixin is part of a cytoskeleton linker protein family with the ability to connect transmembrane proteins to the actin cytoskeleton, promoting cell functions involving a dynamic cytoskeleton such as morphological changes, cell division and migration which are common events of different cell types after stroke. In the healthy adult brain radixin is expressed in Olig2(+) cells throughout the brain and in neural progenitor cells in the subventricular zone. In the current study, we detected a 2.5 fold increase in the number of radixin positive cells in the peri-infarct cortex two weeks after the induction of cortical stroke by photothrombosis. Similarly, the number of Olig2(+) cells increased in the peri-infarct area after stroke; however, the number of radixin(+)/Olig2(+) cells was unchanged. Neural progenitor cells maintained radixin expression on their route to the infarct. More surprising however, was the expression of radixin in activated microglia in the peri-infarct cortex. Seventy percent of Iba1(+) cells expressed radixin after stroke, a population which was not present in the control brain. Furthermore, activation of radixin was predominantly detected in the peri-infarct region of oligodendrocyte progenitors and microglia. The specific location of radixin(+) cells in the peri-infarct region and in microglia suggests a role for radixin in microglial activation after stroke.
Collapse
Affiliation(s)
- Åsa Persson
- Center for Brain Repair and Rehabilitation, Department of Clinical Neuroscience and Rehabilitation, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Sweden
| | | | | | | | | |
Collapse
|
43
|
Chen Y, Yi Q, Liu G, Shen X, Xuan L, Tian Y. Cerebral white matter injury and damage to myelin sheath following whole-brain ischemia. Brain Res 2013; 1495:11-7. [DOI: 10.1016/j.brainres.2012.12.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 12/06/2012] [Accepted: 12/06/2012] [Indexed: 11/16/2022]
|
44
|
Borich MR, Mang C, Boyd LA. Both projection and commissural pathways are disrupted in individuals with chronic stroke: investigating microstructural white matter correlates of motor recovery. BMC Neurosci 2012; 13:107. [PMID: 22931454 PMCID: PMC3547772 DOI: 10.1186/1471-2202-13-107] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Accepted: 08/22/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Complete recovery of motor function after stroke is rare with deficits persisting into the chronic phase of recovery. Diffusion tensor imaging (DTI) can evaluate relationships between white matter microstructure and motor function after stroke. The objective of this investigation was to characterize microstructural fiber integrity of motor and sensory regions of the corpus callosum (CC) and descending motor outputs of the posterior limb of the internal capsule (PLIC) in individuals with chronic stroke and evaluate the relationships between white matter integrity and motor function. RESULTS Standardized measures of upper extremity motor function were measured in thirteen individuals with chronic stroke. Manual dexterity was assessed in thirteen healthy age-matched control participants. DTI scans were completed for each participant. Fractional anisotropy (FA) of a cross-section of sensory and motor regions of the CC and the PLIC bilaterally were quantified. Multivariate analysis of variance evaluated differences between stroke and healthy groups. Correlational analyses were conducted for measures of motor function and FA. The stroke group exhibited reduced FA in the sensory (p = 0.001) region of the CC, contra- (p = 0.032) and ipsilesional (p = 0.001) PLIC, but not the motor region of the CC (p = 0.236). In the stroke group, significant correlations between contralesional PLIC FA and level of physical impairment (p = 0.005), grip strength (p = 0.006) and hand dexterity (p = 0.036) were observed. CONCLUSIONS Microstructural status of the sensory region of the CC is reduced in chronic stroke. Future work is needed to explore relationships between callosal sensorimotor fiber integrity and interhemispheric interactions post-stroke. In addition, contralesional primary motor output tract integrity is uniquely and closely associated with multiple dimensions of motor recovery in the chronic phase of stroke suggesting it may be an important biomarker of overall motor recovery.
Collapse
Affiliation(s)
- Michael R Borich
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, 212-2177 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada
| | - Cameron Mang
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, 212-2177 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada
| | - Lara A Boyd
- Department of Physical Therapy, Faculty of Medicine, University of British Columbia, 212-2177 Wesbrook Mall, Vancouver, British Columbia V6T 1Z3, Canada
- Brain Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| |
Collapse
|
45
|
Valproic acid increases white matter repair and neurogenesis after stroke. Neuroscience 2012; 220:313-21. [PMID: 22704966 DOI: 10.1016/j.neuroscience.2012.06.012] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Revised: 05/23/2012] [Accepted: 06/06/2012] [Indexed: 11/21/2022]
Abstract
Acute treatment of stroke with histone deacetylase (HDAC) inhibitors has been shown to reduce ischemic cell damage; however, it is unclear whether delayed treatment with HDAC inhibitors will contribute to the brain repair and plasticity. In the present study, we investigated the effects of delayed treatment of stroke with a pan HDAC inhibitor, valproic acid (VPA), on white matter injury and neurogenesis during stroke recovery. Administration of VPA at a dose of 100mg/kg for 7 days starting 24h after middle cerebral artery occlusion (MCAo) in rats significantly improved neurological outcome measured 7-28 days post-MCAo. In addition, the VPA treatment significantly increased oligodendrocyte survival and newly generated oligodendrocytes, which was associated with elevation of myelinated axonal density in the ischemic boundary 28 days after MCAo. VPA treatment also increased the expression of glutamate transporter 1 (GLT1) in the ischemic boundary after stroke, and increased acetylated histone H4 expression in neuroblasts and the number of new neurons in striatal ischemic boundary region. This study provides new evidence that the delayed VPA treatment enhances white matter repair and neurogenesis in ischemic brain, which may contribute to improved functional outcome.
Collapse
|
46
|
Di Domenico F, Casalena G, Jia J, Sultana R, Barone E, Cai J, Pierce WM, Cini C, Mancuso C, Perluigi M, Davis CM, Alkayed NJ, Butterfield DA, Butterfield AD. Sex differences in brain proteomes of neuron-specific STAT3-null mice after cerebral ischemia/reperfusion. J Neurochem 2012; 121:680-92. [PMID: 22394374 DOI: 10.1111/j.1471-4159.2012.07721.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Signal transduction and activator of transcription-3 (STAT3) plays an important role in neuronal survival, regeneration and repair after brain injury. We previously demonstrated that STAT3 is activated in brain after cerebral ischemia specifically in neurons. The effect was sex-specific and modulated by sex steroids, with higher activation in females than males. In the current study, we used a proteomics approach to identify downstream proteins affected by ischemia in male and female wild-type (WT) and neuron-specific STAT3 knockout (KO) mice. We established four comparison groups based on the transgenic condition and the hemisphere analyzed, respectively. Moreover, the sexual variable was taken into account and male and female animals were analyzed independently. Results support a role for STAT3 in metabolic, synaptic, structural and transcriptional responses to cerebral ischemia, indeed the adaptive response to ischemia/reperfusion injury is delayed in neuronal-specific STAT3 KO mice. The differences observed between males and females emphasize the importance of sex-specific neuronal survival and repair mechanisms, especially those involving antioxidant and energy-related activities, often caused by sex hormones.
Collapse
Affiliation(s)
- Fabio Di Domenico
- Department of Chemistry, Center of Membrane Sciences, and Sanders-Brown Center on Aging, University of Kentucky, Lexington, Kentucky, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Arai K, Pham LDD, Lo EH. Experimental Platforms for Assessing White Matter Pathophysiology in Stroke. Transl Stroke Res 2012. [DOI: 10.1007/978-1-4419-9530-8_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
48
|
Modifying neurorepair and neuroregenerative factors with tPA and edaravone after transient middle cerebral artery occlusion in rat brain. Brain Res 2011; 1436:168-77. [PMID: 22221736 DOI: 10.1016/j.brainres.2011.12.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2011] [Revised: 12/05/2011] [Accepted: 12/09/2011] [Indexed: 11/20/2022]
Abstract
Changes in expression of neurorepair and neuroregenerative factors were examined after transient cerebral ischemia in relation to the effects of tissue plasminogen activator (tPA) and the free radical scavenger edaravone. Physiological saline or edaravone was injected twice during 90 min of transient middle cerebral artery occlusion (tMCAO) in rats, followed by the same saline or tPA at reperfusion. Sizes of the infarct and protein factors relating to neurorepair and neuroregeneration were examined at 4d after tMCAO. The protein factors examined were: a chondroitin sulfate proteoglycan neurocan, semaphorin type 3A (Sema3A), a myelin-associated glycoprotein receptor (Nogo receptor, Nogo-R), a synaptic regenerative factor (growth associated protein-43, GAP43), and a chemotropic factor netrin receptor (deleted in colorectal cancer, DCC). Two groups treated by edaravone only or edaravone plus tPA showed a reduction in infarct volume compared to the two groups treated by vehicle only or vehicle plus tPA. Immunohistochemistry and western blot analyses indicated that protein expression of neurocan, Sema3A, Nogo-R, GAP43, and DCC was decreased with tPA, but recovered with edaravone. Additive edaravone prevented the reductions of these five proteins induced by tPA. The present study demonstrates for the first time that exogenous tPA reduced protein factors involved in inhibiting and promoting axonal growth, but that edaravone ameliorated such damage in brain repair after acute ischemia.
Collapse
|
49
|
Wang YY, Li N, Huang J, Yang Z, Zhang T. Effects of ionic products from silicon-substituted hydroxyapatite on the rat brain activity: Morris water maze studies and long term potentiation in hippocampal CA1. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2011. [DOI: 10.1016/j.msec.2011.07.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
50
|
Abstract
Neural and oligodendrocyte progenitor cells in the adult brain express Ascl1 (also known as Mash1), a basic helix-loop-helix transcription factor. We examined the progeny and fate of this progenitor population in adult male Ascl1-CreER(TM);R26R-stop-yellow fluorescent protein mice subjected to right middle cerebral occlusion over 60 days after stroke using inducible Cre recombination to label Ascl1-expressing cells at poststroke days 2 to 6 in vivo. Seven days after stroke, a substantial increase in Ascl1 lineage cells was detected in the ipsilateral subventricular zone (SVZ), striatum, and corpus callosum. These cells exhibited proliferating progenitor cell phenotypes (Sox2(+), BrdU(+), and Ki67(+)). Although Ascl1 lineage cells in the ipsilateral SVZ gradually decreased during 14 to 60 days after stroke, Ascl1 lineage cells in the ischemic striatum revealed a remarkable increase during this period. Thirty and sixty days after stroke, Ascl1 lineage cells in the ischemic striatum gave rise to GABAergic neurons and mature oligodendrocytes. In contrast, none of the Ascl1 lineage cells in the contralateral striatum exhibited neuronal and oligodendrocyte phenotypes. Moreover, Ascl1 lineage cells in the corpus callosum were only fated to become mature oligodendrocytes. Our data suggest that Ascl1 lineage cells contribute to stroke-induced neurogenesis and oligodendrogenesis in the adult ischemic brain.
Collapse
|