101
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Boda E, Nato G, Buffo A. Emerging pharmacological approaches to promote neurogenesis from endogenous glial cells. Biochem Pharmacol 2017. [PMID: 28647491 DOI: 10.1016/j.bcp.2017.06.129] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Neurodegenerative disorders are emerging as leading contributors to the global disease burden. While some drug-based approaches have been designed to limit or prevent neuronal loss following acute damage or chronic neurodegeneration, regeneration of functional neurons in the adult Central Nervous System (CNS) still remains an unmet need. In this context, the exploitation of endogenous cell sources has recently gained an unprecedented attention, thanks to the demonstration that, in some CNS regions or under specific circumstances, glial cells can activate spontaneous neurogenesis or can be instructed to produce neurons in the adult mammalian CNS parenchyma. This field of research has greatly advanced in the last years and identified interesting molecular and cellular mechanisms guiding the neurogenic activation/conversion of glia. In this review, we summarize the evolution of the research devoted to understand how resident glia can be directed to produce neurons. We paid particular attention to pharmacologically-relevant approaches exploiting the modulation of niche-associated factors and the application of selected small molecules.
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Affiliation(s)
- Enrica Boda
- Department of Neuroscience Rita Levi-Montalcini, University of Turin, I-10126 Turin, Italy; Neuroscience Institute Cavalieri Ottolenghi, I-10043 Orbassano, Turin, Italy.
| | - Giulia Nato
- Department of Neuroscience Rita Levi-Montalcini, University of Turin, I-10126 Turin, Italy; Neuroscience Institute Cavalieri Ottolenghi, I-10043 Orbassano, Turin, Italy
| | - Annalisa Buffo
- Department of Neuroscience Rita Levi-Montalcini, University of Turin, I-10126 Turin, Italy; Neuroscience Institute Cavalieri Ottolenghi, I-10043 Orbassano, Turin, Italy
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102
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Jones KS, Connor B. Endogenous Brain Repair: Overriding intrinsic lineage determinates through injury-induced micro-environmental signals. NEUROGENESIS 2017; 4:1-5. [PMID: 28596976 DOI: 10.1080/23262133.2017.1297881] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 02/15/2017] [Accepted: 02/16/2017] [Indexed: 01/18/2023]
Abstract
Adult human neurogenesis has generated excitement over the last 2 decades with the idea that endogenous adult stem cells could act as a potential cell source for brain repair after injury. Indeed, many forms of experimentally induced brain injury including stroke and excitotoxic lesioning can promote proliferation from the subventricular zone and mobilise neuroblasts and oligodendrocyte progenitor cells to migrate through brain parenchyma to damaged regions. However the failure of neuroblasts to mature into appropriate neuronal subtypes for cell replacement has been an issue. Recent work by our group and others has indicated that micro-environmental signals released from areas of cell loss may be able to override intrinsic gene expression lineages and covert neuroblasts into oligodendrocyte progenitor cells. This commentary will discuss the enhanced fate plasticity of both adult neural progenitors and parenchymal NG2 cells after injury, and the importance of understanding brain-injury induced micro-environmental signals in the quest toward promoting endogenous regeneration after injury.
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Affiliation(s)
- Kathryn S Jones
- Department of Pharmacology and Clinical Pharmacology, Centre for Brain Research, School of Medical Sciences, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand
| | - Bronwen Connor
- Department of Pharmacology and Clinical Pharmacology, Centre for Brain Research, School of Medical Sciences, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand
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103
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Tan BT, Jiang L, Liu L, Yin Y, Luo ZRX, Long ZY, Li S, Yu LH, Wu YM, Liu Y. Local injection of Lenti-Olig2 at lesion site promotes functional recovery of spinal cord injury in rats. CNS Neurosci Ther 2017; 23:475-487. [PMID: 28452182 DOI: 10.1111/cns.12694] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 03/08/2017] [Accepted: 03/10/2017] [Indexed: 12/17/2022] Open
Abstract
AIMS Olig2 is one of the most critical factors during CNS development, which belongs to b-HLH transcription factor family. Previous reports have shown that Olig2 regulates the remyelination processes in CNS demyelination diseases models. However, the role of Olig2 in contusion spinal cord injury (SCI) and the possible therapeutic effects remain obscure. This study aims to investigate the effects of overexpression Olig2 by lentivirus on adult spinal cord injury rats. METHODS Lenti-Olig2 expression and control Lenti-eGFP vectors were prepared, and virus in a total of 5 μL (108 TU/mL) was locally injected into the injured spinal cord 1.5 mm rostral and caudal near the epicenter. Immunostaining, Western blot, electron microscopy, and CatWalk analyzes were employed to investigate the effects of Olig2 on spinal cord tissue repair and functional recovery. RESULTS Injection of Lenti-Olig2 significantly increased the number of oligodendrocytes lineage cells and enhanced myelination after SCI. More importantly, the introduction of Olig2 greatly improved hindlimb locomotor performances. Other oligodendrocyte-related transcription factors, which were downregulated or upregulated after injury, were reversed by Olig2 induction. CONCLUSIONS Our findings provided the evidence that overexpression Olig2 promotes myelination and locomotor recovery of contusion SCI, which gives us more understanding of Olig2 on spinal cord injury treatment.
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Affiliation(s)
- Bo-Tao Tan
- State Key Laboratory of Trauma, Burns and Combined Injury, Department of Research Institute of Surgery, Daping Hospital, The Third Military Medical University, Chongqing, China.,Department of Rehabilitation Medicine, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Long Jiang
- State Key Laboratory of Trauma, Burns and Combined Injury, Department of Research Institute of Surgery, Daping Hospital, The Third Military Medical University, Chongqing, China
| | - Li Liu
- Department of Brain, The Chongqing Hospital of Traditional Chinese Medicine, Chongqing, China
| | - Ying Yin
- Department of Rehabilitation Medicine, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Ze-Ru-Xin Luo
- Department of Rehabilitation Medicine, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Zai-Yun Long
- State Key Laboratory of Trauma, Burns and Combined Injury, Department of Research Institute of Surgery, Daping Hospital, The Third Military Medical University, Chongqing, China
| | - Sen Li
- State Key Laboratory of Trauma, Burns and Combined Injury, Department of Research Institute of Surgery, Daping Hospital, The Third Military Medical University, Chongqing, China
| | - Le-Hua Yu
- Department of Rehabilitation Medicine, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Ya-Min Wu
- State Key Laboratory of Trauma, Burns and Combined Injury, Department of Research Institute of Surgery, Daping Hospital, The Third Military Medical University, Chongqing, China
| | - Yuan Liu
- State Key Laboratory of Trauma, Burns and Combined Injury, Department of Research Institute of Surgery, Daping Hospital, The Third Military Medical University, Chongqing, China
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104
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Song FE, Huang JL, Lin SH, Wang S, Ma GF, Tong XP. Roles of NG2-glia in ischemic stroke. CNS Neurosci Ther 2017; 23:547-553. [PMID: 28317272 DOI: 10.1111/cns.12690] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 02/23/2017] [Accepted: 02/24/2017] [Indexed: 12/20/2022] Open
Abstract
Recent studies have shown that a widely distributed class of glial cells, termed NG2-glia, engages in rapid signaling with surrounding neurons through direct synaptic contacts in the developing and mature central nervous system (CNS). This unique glial cell group has a typical function of proliferating and differentiating into oligodendrocytes during early development of the brain, which is crucial to axon myelin formation. Therefore, NG2-glia are also called oligodendrocyte precursor cells (OPCs). In vitro and in vivo studies reveal that NG2-glia expressing receptors and ion channels demonstrate functional significance for rapid signaling with neuronal synapses and modulation of neuronal activities in both physiological and pathological conditions. Although it is well known that NG2-glia play an important role in demyelinating diseases such as multiple sclerosis, little is known about how NG2-glia or OPCs impact neurons and brain function following ischemic injury. This review summarizes recent progress on the roles of NG2-glia in ischemic stroke and illustrates new approaches for targeting NG2-glia in the brain to treat this disease.
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Affiliation(s)
- Fei-Er Song
- Discipline of Neuroscience and Department of Anatomy, Histology and Embryology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jia-Lv Huang
- Department of Clinical Medicine, Research-Based Learning training program (RBL2015-29), Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Si-Han Lin
- Department of Clinical Medicine, Research-Based Learning training program (RBL2015-29), Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shuo Wang
- Department of Clinical Medicine, Research-Based Learning training program (RBL2015-29), Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Guo-Fen Ma
- Discipline of Neuroscience and Department of Anatomy, Histology and Embryology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiao-Ping Tong
- Discipline of Neuroscience and Department of Anatomy, Histology and Embryology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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105
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Daneshdoust D, Khalili-Fomeshi M, Ghasemi-Kasman M, Ghorbanian D, Hashemian M, Gholami M, Moghadamnia A, Shojaei A. Pregabalin enhances myelin repair and attenuates glial activation in lysolecithin-induced demyelination model of rat optic chiasm. Neuroscience 2017; 344:148-156. [DOI: 10.1016/j.neuroscience.2016.12.037] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 12/20/2016] [Accepted: 12/22/2016] [Indexed: 11/26/2022]
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106
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Duy PQ, Berberoglu MA, Beattie CE, Hall CW. Cellular responses to recurrent pentylenetetrazole-induced seizures in the adult zebrafish brain. Neuroscience 2017; 349:118-127. [PMID: 28238851 DOI: 10.1016/j.neuroscience.2017.02.032] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 02/07/2017] [Accepted: 02/15/2017] [Indexed: 10/20/2022]
Abstract
A seizure is a sustained increase in brain electrical activity that can result in loss of consciousness and injury. Understanding how the brain responds to seizures is important for development of new treatment strategies for epilepsy, a neurological condition characterized by recurrent and unprovoked seizures. Pharmacological induction of seizures in rodent models results in a myriad of cellular alterations, including inflammation, angiogenesis, and adult neurogenesis. The purpose of this study is to investigate the cellular responses to recurrent pentylenetetrazole seizures in the adult zebrafish brain. We subjected zebrafish to five once-daily pentylenetetrazole-induced seizures and characterized the cellular consequences of these seizures. In response to recurrent seizures, we found histologic evidence of vasodilatation, perivascular leukocyte egress and leukocyte proliferation suggesting seizure-induced acute CNS inflammation. We also found evidence of increased proliferation, neurogenesis, and reactive gliosis following pentylenetetrazole-induced seizures. Collectively, our results suggest that the cellular responses to seizures in the adult zebrafish brain are similar to those observed in mammalian brains.
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Affiliation(s)
- Phan Q Duy
- Department of Neuroscience, The Ohio State University, Columbus, OH 43210, USA
| | - Michael A Berberoglu
- Department of Molecular Genetics and Biological Chemistry and Pharmacology, The Ohio State University, Columbus, OH 43210, USA
| | - Christine E Beattie
- Department of Neuroscience, The Ohio State University, Columbus, OH 43210, USA.
| | - Charles W Hall
- Premier Health Clinical Neuroscience Institute, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
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107
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Jäkel S, Dimou L. Glial Cells and Their Function in the Adult Brain: A Journey through the History of Their Ablation. Front Cell Neurosci 2017; 11:24. [PMID: 28243193 PMCID: PMC5303749 DOI: 10.3389/fncel.2017.00024] [Citation(s) in RCA: 268] [Impact Index Per Article: 38.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 01/26/2017] [Indexed: 01/06/2023] Open
Abstract
Glial cells, consisting of microglia, astrocytes, and oligodendrocyte lineage cells as their major components, constitute a large fraction of the mammalian brain. Originally considered as purely non-functional glue for neurons, decades of research have highlighted the importance as well as further functions of glial cells. Although many aspects of these cells are well characterized nowadays, the functions of the different glial populations in the brain under both physiological and pathological conditions remain, at least to a certain extent, unresolved. To tackle these important questions, a broad range of depletion approaches have been developed in which microglia, astrocytes, or oligodendrocyte lineage cells (i.e., NG2-glia and oligodendrocytes) are specifically ablated from the adult brain network with a subsequent analysis of the consequences. As the different glial populations are very heterogeneous, it is imperative to specifically ablate single cell populations instead of inducing cell death in all glial cells in general. Thanks to modern genetic manipulation methods, the approaches can now directly be targeted to the cell type of interest making the ablation more specific compared to general cell ablation approaches that have been used earlier on. In this review, we will give a detailed summary on different glial ablation studies, focusing on the adult mouse central nervous system and the functional readouts. We will also provide an outlook on how these approaches could be further exploited in the future.
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Affiliation(s)
- Sarah Jäkel
- Physiological Genomics, Biomedical Center, Ludwig-Maximilians UniversityMunich, Germany; MRC Centre for Regenerative Medicine, University of EdinburghEdinburgh, UK
| | - Leda Dimou
- Physiological Genomics, Biomedical Center, Ludwig-Maximilians UniversityMunich, Germany; Munich Cluster for Systems NeurologyMunich, Germany; Molecular and Translational Neuroscience, Department of Neurology, University of UlmUlm, Germany
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108
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Kazanis I, Evans KA, Andreopoulou E, Dimitriou C, Koutsakis C, Karadottir RT, Franklin RJM. Subependymal Zone-Derived Oligodendroblasts Respond to Focal Demyelination but Fail to Generate Myelin in Young and Aged Mice. Stem Cell Reports 2017; 8:685-700. [PMID: 28196689 PMCID: PMC5355571 DOI: 10.1016/j.stemcr.2017.01.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 01/10/2017] [Accepted: 01/10/2017] [Indexed: 01/05/2023] Open
Abstract
Two populations of oligodendrogenic progenitors co-exist within the corpus callosum (CC) of the adult mouse. Local, parenchymal oligodendrocyte progenitor cells (pOPCs) and progenitors generated in the subependymal zone (SEZ) cytogenic niche. pOPCs are committed perinatally and retain their numbers through self-renewing divisions, while SEZ-derived cells are relatively “young,” being constantly born from neural stem cells. We compared the behavior of these populations, labeling SEZ-derived cells using hGFAP:CreErt2 mice, within the homeostatic and regenerating CC of the young-adult and aging brain. We found that SEZ-derived oligodendroglial progenitors have limited self-renewing potential and are therefore not bona fide OPCs but rather “oligodendroblasts” more similar to the neuroblasts of the neurogenic output of the SEZ. In the aged CC their mitotic activity is much reduced, although they still act as a “fast-response element” to focal demyelination. In contrast to pOPCs, they fail to generate mature myelinating oligodendrocytes at all ages studied. SEZ-derived cells in the CC are oligodendroblasts and not OPCs Oligodendroblasts have limited self-renewal capacity and do not make myelin Oligodendroblasts respond rapidly after demyelination Aging does not affect the oligodendroblast-pOPC balance
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Affiliation(s)
- Ilias Kazanis
- Wellcome Trust-MRC Cambridge Stem Cell Biology Institute, University of Cambridge, Cambridge CB2 0AH, UK; Lab of Developmental Biology, Department of Biology, University of Patras, Patras 26500, Greece.
| | - Kimberley A Evans
- Wellcome Trust-MRC Cambridge Stem Cell Biology Institute, University of Cambridge, Cambridge CB2 0AH, UK
| | - Evangelia Andreopoulou
- Lab of Developmental Biology, Department of Biology, University of Patras, Patras 26500, Greece
| | - Christina Dimitriou
- Lab of Developmental Biology, Department of Biology, University of Patras, Patras 26500, Greece
| | - Christos Koutsakis
- Lab of Developmental Biology, Department of Biology, University of Patras, Patras 26500, Greece
| | | | - Robin J M Franklin
- Wellcome Trust-MRC Cambridge Stem Cell Biology Institute, University of Cambridge, Cambridge CB2 0AH, UK.
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109
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Klempin F, Gertz K, Kronenberg G. Redox homeostasis: unlocking the bottleneck in glia-to-neuron conversion. Stem Cell Investig 2017; 4:7. [PMID: 28217709 DOI: 10.21037/sci.2017.01.07] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2016] [Accepted: 12/29/2016] [Indexed: 01/07/2023]
Affiliation(s)
- Friederike Klempin
- Klinik und Poliklinik für Neurologie, Charité Campus Mitte, Charité - Universitätsmedizin Berlin, 10117 Berlin, Germany;; Max Delbruck Center for Molecular Medicine (MDC), 13125 Berlin, Germany
| | - Karen Gertz
- Klinik und Poliklinik für Neurologie, Charité Campus Mitte, Charité - Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Golo Kronenberg
- Klinik und Poliklinik für Neurologie, Charité Campus Mitte, Charité - Universitätsmedizin Berlin, 10117 Berlin, Germany;; Klinik und Poliklinik für Psychiatrie und Psychotherapie, Charité Campus Mitte, Charité - Universitätsmedizin Berlin, 10117 Berlin, Germany;; Klinik und Poliklinik für Psychiatrie und Psychotherapie, Universitätsmedizin Rostock, 18147 Rostock, Germany
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110
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Torper O, Götz M. Brain repair from intrinsic cell sources: Turning reactive glia into neurons. PROGRESS IN BRAIN RESEARCH 2017; 230:69-97. [PMID: 28552236 DOI: 10.1016/bs.pbr.2016.12.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The replacement of lost neurons in the brain due to injury or disease holds great promise for the treatment of neurological disorders. However, logistical and ethical hurdles in obtaining and maintaining viable cells for transplantation have proven difficult to overcome. In vivo reprogramming offers an alternative, to bypass many of the restrictions associated with an exogenous cell source as it relies on a source of cells already present in the brain. Recent studies have demonstrated the possibility to target and reprogram glial cells into functional neurons with high efficiency in the murine brain, using virally delivered transcription factors. In this chapter, we explore the different populations of glial cells, how they react to injury and how they can be exploited for reprogramming purposes. Further, we review the most significant publications and how they have contributed to the understanding of key aspects in direct reprogramming needed to take into consideration, like timing, cell type targeted, and regional differences. Finally, we discuss future challenges and what remains to be explored in order to determine the potential of in vivo reprogramming for future brain repair.
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Affiliation(s)
- Olof Torper
- Physiological Genomics, Biomedical Center, Ludwig-Maximilians University Munich, Planegg, Germany; Institute of Stem Cell Research, Helmholtz Center Munich, Munich, Germany; SYNERGY, Excellence Cluster of Systems Neurology, Biomedical Center, Ludwig-Maximilians University Munich, Planegg, Germany
| | - Magdalena Götz
- Physiological Genomics, Biomedical Center, Ludwig-Maximilians University Munich, Planegg, Germany; Institute of Stem Cell Research, Helmholtz Center Munich, Munich, Germany; SYNERGY, Excellence Cluster of Systems Neurology, Biomedical Center, Ludwig-Maximilians University Munich, Planegg, Germany.
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111
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Hackett AR, Lee JK. Understanding the NG2 Glial Scar after Spinal Cord Injury. Front Neurol 2016; 7:199. [PMID: 27895617 PMCID: PMC5108923 DOI: 10.3389/fneur.2016.00199] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 10/31/2016] [Indexed: 01/05/2023] Open
Abstract
NG2 cells, also known as oligodendrocyte progenitor cells, are located throughout the central nervous system and serve as a pool of progenitors to differentiate into oligodendrocytes. In response to spinal cord injury (SCI), NG2 cells increase their proliferation and differentiation into remyelinating oligodendrocytes. While astrocytes are typically associated with being the major cell type in the glial scar, many NG2 cells also accumulate within the glial scar but their function remains poorly understood. Similar to astrocytes, these cells hypertrophy, upregulate expression of chondroitin sulfate proteoglycans, inhibit axon regeneration, contribute to the glial-fibrotic scar border, and some even differentiate into astrocytes. Whether NG2 cells also have a role in other astrocyte functions, such as preventing the spread of infiltrating leukocytes and expression of inflammatory cytokines, is not yet known. Thus, NG2 cells are not only important for remyelination after SCI but are also a major component of the glial scar with functions that overlap with astrocytes in this region. In this review, we describe the signaling pathways important for the proliferation and differentiation of NG2 cells, as well as the role of NG2 cells in scar formation and tissue repair.
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Affiliation(s)
- Amber R. Hackett
- Miami Project to Cure Paralysis, The Neuroscience Graduate Program, Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Jae K. Lee
- Miami Project to Cure Paralysis, The Neuroscience Graduate Program, Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami, FL, USA
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112
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Grealish S, Drouin-Ouellet J, Parmar M. Brain repair and reprogramming: the route to clinical translation. J Intern Med 2016; 280:265-75. [PMID: 27539906 DOI: 10.1111/joim.12475] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The adult brain has a very limited capacity for generation of new neurons, and neurogenesis only takes place in restricted regions. Some evidence for neurogenesis after injury has been reported, but few, if any, neurons are replaced after brain injury or degeneration, and the permanent loss of neurons leads to long-term disability and loss of brain function. For decades, researchers have been developing cell transplantation using exogenous cell sources for brain repair, and this method has now been shown to successfully restore lost function in experimental and clinical trials. Here, we review the development of cell-replacement strategies for brain repair in Parkinson's disease using the example of human foetal brain cells being successfully translated from preclinical findings to clinical trials. These trials demonstrate that cell-replacement therapy is a viable option for patients with Parkinson's disease, but more importantly also show how the limited availability of foetal cells calls for development of novel cell sources and methods for generating new neurons for brain repair. We focus on new stem cell sources that are on the threshold of clinical application for brain repair and discuss emerging cellular reprogramming technologies. Reviewing the current status of direct neural conversion, both in vitro and in vivo, where somatic cells are directly reprogrammed into functional neurons without passing through a stem cell intermediate, we conclude that both methods result in the successful replacement of new neurons that mature and integrate into the host brain. Thus, this new field shows great promise for future brain repair, although much work is still needed in preclinical animal models before it can be seriously considered for clinical applications.
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Affiliation(s)
- S Grealish
- Developmental and Regenerative Neurobiology, Department of Experimental Medical Science, Wallenberg Neuroscience Center, Lund University, Lund, Sweden.,Lund Stem Cell Center, Lund University, Lund, Sweden
| | - J Drouin-Ouellet
- Developmental and Regenerative Neurobiology, Department of Experimental Medical Science, Wallenberg Neuroscience Center, Lund University, Lund, Sweden.,Lund Stem Cell Center, Lund University, Lund, Sweden
| | - M Parmar
- Developmental and Regenerative Neurobiology, Department of Experimental Medical Science, Wallenberg Neuroscience Center, Lund University, Lund, Sweden.,Lund Stem Cell Center, Lund University, Lund, Sweden
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113
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Jessberger S. Stem Cell-Mediated Regeneration of the Adult Brain. Transfus Med Hemother 2016; 43:321-326. [PMID: 27781019 DOI: 10.1159/000447646] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 06/10/2016] [Indexed: 12/16/2022] Open
Abstract
Acute or chronic injury of the adult mammalian brain is often associated with persistent functional deficits as its potential for regeneration and capacity to rebuild lost neural structures is limited. However, the discovery that neural stem cells (NSCs) persist throughout life in discrete regions of the brain, novel approaches to induce the formation of neuronal and glial cells, and recently developed strategies to generate tissue for exogenous cell replacement strategies opened novel perspectives how to regenerate the adult brain. Here, we will review recently developed approaches for brain repair and discuss future perspectives that may eventually allow for developing novel treatment strategies in acute and chronic brain injury.
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Affiliation(s)
- Sebastian Jessberger
- Laboratory of Neural Plasticity, Brain Research Institute, Faculty of Medicine and Science, University of Zurich, Zurich, Switzerland
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114
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Chang EH, Adorjan I, Mundim MV, Sun B, Dizon MLV, Szele FG. Traumatic Brain Injury Activation of the Adult Subventricular Zone Neurogenic Niche. Front Neurosci 2016; 10:332. [PMID: 27531972 PMCID: PMC4969304 DOI: 10.3389/fnins.2016.00332] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 06/30/2016] [Indexed: 01/07/2023] Open
Abstract
Traumatic brain injury (TBI) is common in both civilian and military life, placing a large burden on survivors and society. However, with the recognition of neural stem cells in adult mammals, including humans, came the possibility to harness these cells for repair of damaged brain, whereas previously this was thought to be impossible. In this review, we focus on the rodent adult subventricular zone (SVZ), an important neurogenic niche within the mature brain in which neural stem cells continue to reside. We review how the SVZ is perturbed following various animal TBI models with regards to cell proliferation, emigration, survival, and differentiation, and we review specific molecules involved in these processes. Together, this information suggests next steps in attempting to translate knowledge from TBI animal models into human therapies for TBI.
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Affiliation(s)
- Eun Hyuk Chang
- Samsung Biomedical Research Institute, Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd. Seoul, South Korea
| | - Istvan Adorjan
- Department of Physiology, Anatomy and Genetics, University of OxfordOxford, UK; Department of Anatomy, Histology and Embryology, Semmelweis UniversityBudapest, Hungary
| | - Mayara V Mundim
- Department of Biochemistry, Universidade Federal de São Paulo São Paulo, Brazil
| | - Bin Sun
- Department of Physiology, Anatomy and Genetics, University of Oxford Oxford, UK
| | - Maria L V Dizon
- Department of Pediatrics, Prentice Women's Hospital, Northwestern University Feinberg School of Medicine Chicago, IL, USA
| | - Francis G Szele
- Department of Physiology, Anatomy and Genetics, University of Oxford Oxford, UK
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115
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Pellegrino RM, Boda E, Montarolo F, Boero M, Mezzanotte M, Saglio G, Buffo A, Roetto A. Transferrin Receptor 2 Dependent Alterations of Brain Iron Metabolism Affect Anxiety Circuits in the Mouse. Sci Rep 2016; 6:30725. [PMID: 27477597 PMCID: PMC4967901 DOI: 10.1038/srep30725] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 07/06/2016] [Indexed: 12/21/2022] Open
Abstract
The Transferrin Receptor 2 (Tfr2) modulates systemic iron metabolism through the regulation of iron regulator Hepcidin (Hepc) and Tfr2 inactivation causes systemic iron overload. Based on data demonstrating Tfr2 expression in brain, we analysed Tfr2-KO mice in order to examine the molecular, histological and behavioural consequences of Tfr2 silencing in this tissue. Tfr2 abrogation caused an accumulation of iron in specific districts in the nervous tissue that was not accompanied by a brain Hepc response. Moreover, Tfr2-KO mice presented a selective overactivation of neurons in the limbic circuit and the emergence of an anxious-like behaviour. Furthermore, microglial cells showed a particular sensitivity to iron perturbation. We conclude that Tfr2 is a key regulator of brain iron homeostasis and propose a role for Tfr2 alpha in the regulation of anxiety circuits.
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Affiliation(s)
- Rosa Maria Pellegrino
- Department of Clinical and Biological Sciences, University of Torino, Turin, Italy.,AOU San Luigi Regione Gonzole 10043 Orbassano Turin, Italy
| | - Enrica Boda
- Department of Neuroscience Rita Levi-Montalcini, University of Torino, Turin, Italy.,Neuroscience Institute Cavalieri Ottolenghi Regione Gonzole 10043 Orbassano Turin, Italy
| | - Francesca Montarolo
- Neuroscience Institute Cavalieri Ottolenghi Regione Gonzole 10043 Orbassano Turin, Italy
| | - Martina Boero
- Department of Clinical and Biological Sciences, University of Torino, Turin, Italy.,AOU San Luigi Regione Gonzole 10043 Orbassano Turin, Italy
| | - Mariarosa Mezzanotte
- Department of Clinical and Biological Sciences, University of Torino, Turin, Italy.,AOU San Luigi Regione Gonzole 10043 Orbassano Turin, Italy
| | - Giuseppe Saglio
- Department of Clinical and Biological Sciences, University of Torino, Turin, Italy.,AOU San Luigi Regione Gonzole 10043 Orbassano Turin, Italy
| | - Annalisa Buffo
- Department of Neuroscience Rita Levi-Montalcini, University of Torino, Turin, Italy.,Neuroscience Institute Cavalieri Ottolenghi Regione Gonzole 10043 Orbassano Turin, Italy
| | - Antonella Roetto
- Department of Clinical and Biological Sciences, University of Torino, Turin, Italy.,AOU San Luigi Regione Gonzole 10043 Orbassano Turin, Italy
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116
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Götz M, Nakafuku M, Petrik D. Neurogenesis in the Developing and Adult Brain-Similarities and Key Differences. Cold Spring Harb Perspect Biol 2016; 8:cshperspect.a018853. [PMID: 27235475 DOI: 10.1101/cshperspect.a018853] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Adult neurogenesis in the mammalian brain is often viewed as a continuation of neurogenesis at earlier, developmental stages. Here, we will critically review the extent to which this is the case highlighting similarities as well as key differences. Although many transcriptional regulators are shared in neurogenesis at embryonic and adult stages, recent findings on the molecular mechanisms by which these neuronal fate determinants control fate acquisition and maintenance have revealed profound differences between development and adulthood. Importantly, adult neurogenesis occurs in a gliogenic environment, hence requiring adult-specific additional and unique mechanisms of neuronal fate specification and maintenance. Thus, a better understanding of the molecular logic for continuous adult neurogenesis provides important clues to develop strategies to manipulate endogenous stem cells for the purpose of repair.
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Affiliation(s)
- Magdalena Götz
- Institute of Stem Cell Research, Helmholtz Center Munich, 85764 Neuherberg, Munich, Germany Physiological Genomics, Biomedical Center, Ludwig-Maximilians-University, 80336 Munich, Germany Synergy, Munich Cluster for Systems Neurology, 81377 Munich, Germany
| | - Masato Nakafuku
- Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45140 Departments of Pediatrics and Neurosurgery, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267
| | - David Petrik
- Institute of Stem Cell Research, Helmholtz Center Munich, 85764 Neuherberg, Munich, Germany Physiological Genomics, Biomedical Center, Ludwig-Maximilians-University, 80336 Munich, Germany
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117
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Rusznák Z, Henskens W, Schofield E, Kim WS, Fu Y. Adult Neurogenesis and Gliogenesis: Possible Mechanisms for Neurorestoration. Exp Neurobiol 2016; 25:103-12. [PMID: 27358578 PMCID: PMC4923354 DOI: 10.5607/en.2016.25.3.103] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 06/08/2016] [Accepted: 06/08/2016] [Indexed: 12/22/2022] Open
Abstract
The subgranular zone (SGZ) and subventricular zone (SVZ) are developmental remnants of the germinal regions of the brain, hence they retain the ability to generate neuronal progenitor cells in adult life. Neurogenesis in adult brain has an adaptive function because newly produced neurons can integrate into and modify existing neuronal circuits. In contrast to the SGZ and SVZ, other brain regions have a lower capacity to produce new neurons, and this usually occurs via parenchymal and periventricular cell genesis. Compared to neurogenesis, gliogenesis occurs more prevalently in the adult mammalian brain. Under certain circumstances, interaction occurs between neurogenesis and gliogenesis, facilitating glial cells to transform into neuronal lineage. Therefore, modulating the balance between neurogenesis and gliogenesis may present a new perspective for neurorestoration, especially in diseases associated with altered neurogenesis and/or gliogenesis, cell loss, or disturbed homeostasis of cellular constitution. The present review discusses important neuroanatomical features of adult neurogenesis and gliogenesis, aiming to explore how these processes could be modulated toward functional repair of the adult brain.
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Affiliation(s)
- Zoltán Rusznák
- Neuroscience Research Australia, Sydney, NSW 2031, Australia
| | - Willem Henskens
- Neuroscience Research Australia, Sydney, NSW 2031, Australia.; Prince of Wales Clinical School, UNSW Medicine, University of New South Wales, Sydney, NSW 2052, Australia
| | - Emma Schofield
- Neuroscience Research Australia, Sydney, NSW 2031, Australia
| | - Woojin S Kim
- Neuroscience Research Australia, Sydney, NSW 2031, Australia.; School of Medical Sciences, University of New South Wales, Sydney, NSW 2052, Australia
| | - YuHong Fu
- Neuroscience Research Australia, Sydney, NSW 2031, Australia.; School of Medical Sciences, University of New South Wales, Sydney, NSW 2052, Australia
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118
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Yi M, Dou F, Lu Q, Yu Z, Chen H. Activation of the KCa3.1 channel contributes to traumatic scratch injury-induced reactive astrogliosis through the JNK/c-Jun signaling pathway. Neurosci Lett 2016; 624:62-71. [DOI: 10.1016/j.neulet.2016.05.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 04/26/2016] [Accepted: 05/03/2016] [Indexed: 11/30/2022]
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119
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Jones KS, Connor BJ. The Effect of Pro-Neurogenic Gene Expression on Adult Subventricular Zone Precursor Cell Recruitment and Fate Determination After Excitotoxic Brain Injury. J Stem Cells Regen Med 2016. [PMID: 27397999 PMCID: PMC4929891 DOI: 10.46582/jsrm.1201005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Despite the presence of on-going neurogenesis in the adult mammalian brain, neurons are generally not replaced after injury. Using a rodent model of excitotoxic cell loss and retroviral (RV) lineage tracing, we previously demonstrated transient recruitment of precursor cells from the subventricular zone (SVZ) into the lesioned striatum. In the current study we determined that these cells included migratory neuroblasts and oligodendrocyte precursor cells (OPC), with the predominant response from glial cells. We attempted to override this glial response by ectopic expression of the pro-neurogenic genes Pax6 or Dlx2 in the adult rat SVZ following quinolinic acid lesioning. RV-Dlx2 over-expression stimulated repair at a previously non-neurogenic time point by enhancing neuroblast recruitment and the percentage of cells that retained a neuronal fate within the lesioned area, compared to RV-GFP controls. RV-Pax6 expression was unsuccessful at inhibiting glial fate and intriguingly, increased OPC cell numbers with no change in neuronal recruitment. These findings suggest that gene choice is important when attempting to augment endogenous repair as the lesioned environment can overcome pro-neurogenic gene expression. Dlx2 over-expression however was able to partially overcome an anti-neuronal environment and therefore is a promising candidate for further study of striatal regeneration.
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Affiliation(s)
- Kathryn S Jones
- Centre for Brain Research, Department of Pharmacology and Clinical Pharmacology, School of Medical Science, Faculty of Medical and Health Sciences, University of Auckland
| | - Bronwen J Connor
- Centre for Brain Research, Department of Pharmacology and Clinical Pharmacology, School of Medical Science, Faculty of Medical and Health Sciences, University of Auckland
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120
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Xu H, Wang Y, He Z, Yang H, Gao WQ. Direct conversion of mouse fibroblasts to GABAergic neurons with combined medium without the introduction of transcription factors or miRNAs. Cell Cycle 2016; 14:2451-60. [PMID: 26114472 DOI: 10.1080/15384101.2015.1060382] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Degeneration or loss of GABAergic neurons frequently may lead to many neuropsychiatric disorders such as epilepsy and autism spectrum disorders. So far no clinically effective therapies can slow and halt the progression of these diseases. Cell-replacement therapy is a promising strategy for treatment of these neuropsychiatric diseases. Although increasing evidence showed that mammalian somatic cells can be directly converted into functional neurons using specific transcription factors or miRNAs via virus delivery, the application of these induced neurons is potentially problematic, due to integration of vectors into the host genome, which results in the disruption or dysfunction of nearby genes. Here, we show that mouse fibroblasts could be efficiently reprogrammed into GABAergic neurons in a combined medium composed of conditioned medium from neurotrophin-3 modified Olfactory Ensheathing Cells (NT3-OECs) plus SB431542, GDNF and RA. Following 3 weeks of induction, these cells derived from fibroblasts acquired the morphological and phenotypical GABAerigic neuronal properties, as demonstrated by the expression of neuronal markers including Tuj1, NeuN, Neurofilament-L, GABA, GABA receptors and GABA transporter 1. More importantly, these converted cells acquired neuronal functional properties such as synapse formation and increasing intracellular free calcium influx when treated with BayK, a specific activator of L-type calcium channel. Therefore, our findings demonstrate for the first time that fibroblasts can be directly converted into GABAergic neurons without ectopic expression of specific transcription factors or miRNA. This study may provide a promising cell source for the application of cell replacement therapy in neuropsychiatric disorders.
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Affiliation(s)
- Huiming Xu
- a State Key Laboratory of Oncogenes and Related Genes; Renji-MedX Clinical Stem Cell Research Center; Ren Ji Hospital; School of Medicine; Shanghai Jiao Tong University ; Shangha , China
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121
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Berninger B, Jessberger S. Engineering of Adult Neurogenesis and Gliogenesis. Cold Spring Harb Perspect Biol 2016; 8:cshperspect.a018861. [PMID: 27091941 DOI: 10.1101/cshperspect.a018861] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Neural stem/progenitor cells (NSPCs) retain their ability to generate newborn neurons throughout life in the mammalian brain. Here, we describe how recently developed virus- and transgenesis-based techniques will help us (1) to understand the functional effects of neurogenesis in health and disease, (2) to design novel approaches to harness the potential for NSPC-associated endogenous repair, and (3) to induce the generation of neurons outside the main neurogenic niches in the adult brain.
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Affiliation(s)
- Benedikt Berninger
- Adult Neurogenesis and Cellular Reprogramming, Institute of Physiological Chemistry & Focus Program Translational Neuroscience, University Medical Center, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
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122
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Levine J. The reactions and role of NG2 glia in spinal cord injury. Brain Res 2016; 1638:199-208. [PMID: 26232070 PMCID: PMC4732922 DOI: 10.1016/j.brainres.2015.07.026] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 07/02/2015] [Accepted: 07/18/2015] [Indexed: 01/06/2023]
Abstract
Oligodendrocyte precursor cells (OPCs) react rapidly to brain and spinal cord injuries. This reaction is characterized by the retraction of cell processes, cell body swelling and increased expression of the NG2 chondroitin sulfate proteoglycan. Reactive OPCs rapidly divide and accumulate surrounding the injury site where they become major cellular components of the glial scar. The glial reaction to injury is an attempt to restore normal homeostasis and re-establish the glia limitans but the exact role of reactive OPCs in these processes is not well understood. Traumatic injury results in extensive oligodendrocyte cell death and the proliferating OPCs generate the large number of precursor cells necessary for remyelination. Reactive OPCs, however, also are a source of axon-growth inhibitory proteoglycans and may interact with invading inflammatory cells in complex ways. Here, I discuss these and other properties of OPCs after spinal cord injury. Understanding the regulation of these disparate properties may lead to new therapeutic approaches to devastating injuries of the spinal cord. This article is part of a Special Issue entitled SI:NG2-glia(Invited only).
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Affiliation(s)
- Joel Levine
- Department of Neurobiology and Behavior, Stonybrook University, Stony Brook, NY 11794, USA.
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123
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Neural stem/progenitor cells in Alzheimer's disease. THE YALE JOURNAL OF BIOLOGY AND MEDICINE 2016; 89:23-35. [PMID: 27505014 PMCID: PMC4797833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Alzheimer's disease (AD) is the most prevalent neurodegenerative disease and a worldwide health challenge. Different therapeutic approaches are being developed to reverse or slow the loss of affected neurons. Another plausible therapeutic way that may complement the studies is to increase the survival of existing neurons by mobilizing the existing neural stem/progenitor cells (NSPCs) - i.e. "induce their plasticity" - to regenerate lost neurons despite the existing pathology and unfavorable environment. However, there is controversy about how NSPCs are affected by the unfavorable toxic environment during AD. In this review, we will discuss the use of stem cells in neurodegenerative diseases and in particular how NSPCs affect the AD pathology and how neurodegeneration affects NSPCs. In the end of this review, we will discuss how zebrafish as a useful model organism with extensive regenerative ability in the brain might help to address the molecular programs needed for NSPCs to respond to neurodegeneration by enhanced neurogenesis.
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124
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Abstract
Acute or chronic injury to the adult brain often results in substantial loss of neural tissue and subsequent permanent functional impairment. Over the last two decades, a number of approaches have been developed to harness the regenerative potential of neural stem cells and the existing fate plasticity of neural cells in the nervous system to prevent tissue loss or to enhance structural and functional regeneration upon injury. Here, we review recent advances of stem cell-associated neural repair in the adult brain, discuss current challenges and limitations, and suggest potential directions to foster the translation of experimental stem cell therapies into the clinic.
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Affiliation(s)
- Sebastian Jessberger
- Laboratory of Neural Plasticity, Brain Research Institute, Faculty of Medicine and Science, University of Zurich, Zurich, Switzerland
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125
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Bosco A, Breen KT, Anderson SR, Steele MR, Calkins DJ, Vetter ML. Glial coverage in the optic nerve expands in proportion to optic axon loss in chronic mouse glaucoma. Exp Eye Res 2016; 150:34-43. [PMID: 26851485 DOI: 10.1016/j.exer.2016.01.014] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 12/21/2015] [Accepted: 01/23/2016] [Indexed: 01/08/2023]
Abstract
Within the white matter, axonal loss by neurodegeneration is coupled to glial cell changes in gene expression, structure and function commonly termed gliosis. Recently, we described the highly variable expansion of gliosis alebosco@neuro.utah.edu in degenerative optic nerves from the DBA/2J mouse model of chronic, age-related glaucoma. Here, to estimate and compare the levels of axonal loss with the expansion of glial coverage and axonal degeneration in DBA/2J nerves, we combined semiautomatic axon counts with threshold-based segmentation of total glial/scar areas and degenerative axonal profiles in plastic cross-sections. In nerves ranging from mild to severe degeneration, we found that the progression of axonal dropout is coupled to an increase of gliotic area. We detected a strong correlation between axon loss and the aggregate coverage by glial cells and scar, whereas axon loss did not correlate with the small fraction of degenerating profiles. Nerves with low to medium levels of axon loss displayed moderate glial reactivity, consisting of hypertrophic astrocytes, activated microglia and normal distribution of oligodendrocytes, with minimal reorganization of the tissue architecture. In contrast, nerves with extensive axonal loss showed prevalent rearrangement of the nerve, with loss of axon fascicle territories and enlarged or almost continuous gliotic and scar domains, containing reactive astrocytes, oligodendrocytes and activated microglia. These findings support the value of optic nerve gliotic expansion as a quantitative estimate of optic neuropathy that correlates with axon loss, applicable to grade the severity of optic nerve damage in mouse chronic glaucoma.
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Affiliation(s)
- Alejandra Bosco
- Department of Neurobiology and Anatomy, School of Medicine, University of Utah, Salt Lake City, UT 84112, United States.
| | - Kevin T Breen
- Department of Neurobiology and Anatomy, School of Medicine, University of Utah, Salt Lake City, UT 84112, United States
| | - Sarah R Anderson
- Department of Neurobiology and Anatomy, School of Medicine, University of Utah, Salt Lake City, UT 84112, United States
| | - Michael R Steele
- Department of Neurobiology and Anatomy, School of Medicine, University of Utah, Salt Lake City, UT 84112, United States
| | - David J Calkins
- Department of Ophthalmology and Visual Sciences, Vanderbilt University Medical Center, Nashville, TN 37205, United States
| | - Monica L Vetter
- Department of Neurobiology and Anatomy, School of Medicine, University of Utah, Salt Lake City, UT 84112, United States
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126
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Gascón S, Murenu E, Masserdotti G, Ortega F, Russo GL, Petrik D, Deshpande A, Heinrich C, Karow M, Robertson SP, Schroeder T, Beckers J, Irmler M, Berndt C, Angeli JPF, Conrad M, Berninger B, Götz M. Identification and Successful Negotiation of a Metabolic Checkpoint in Direct Neuronal Reprogramming. Cell Stem Cell 2015; 18:396-409. [PMID: 26748418 DOI: 10.1016/j.stem.2015.12.003] [Citation(s) in RCA: 254] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 11/07/2015] [Accepted: 12/10/2015] [Indexed: 11/16/2022]
Abstract
Despite the widespread interest in direct neuronal reprogramming, the mechanisms underpinning fate conversion remain largely unknown. Our study revealed a critical time point after which cells either successfully convert into neurons or succumb to cell death. Co-transduction with Bcl-2 greatly improved negotiation of this critical point by faster neuronal differentiation. Surprisingly, mutants with reduced or no affinity for Bax demonstrated that Bcl-2 exerts this effect by an apoptosis-independent mechanism. Consistent with a caspase-independent role, ferroptosis inhibitors potently increased neuronal reprogramming by inhibiting lipid peroxidation occurring during fate conversion. Genome-wide expression analysis confirmed that treatments promoting neuronal reprogramming elicit an anti-oxidative stress response. Importantly, co-expression of Bcl-2 and anti-oxidative treatments leads to an unprecedented improvement in glial-to-neuron conversion after traumatic brain injury in vivo, underscoring the relevance of these pathways in cellular reprograming irrespective of cell type in vitro and in vivo.
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Affiliation(s)
- Sergio Gascón
- Physiological Genomics, Biomedical Center Ludwig-Maximilians-University Munich, 80336 Munich, Germany; Institute for Stem Cell Research, Helmholtz Center Munich, 85764 Neuherberg, Germany.
| | - Elisa Murenu
- Physiological Genomics, Biomedical Center Ludwig-Maximilians-University Munich, 80336 Munich, Germany; Institute for Stem Cell Research, Helmholtz Center Munich, 85764 Neuherberg, Germany
| | - Giacomo Masserdotti
- Physiological Genomics, Biomedical Center Ludwig-Maximilians-University Munich, 80336 Munich, Germany; Institute for Stem Cell Research, Helmholtz Center Munich, 85764 Neuherberg, Germany
| | - Felipe Ortega
- Physiological Genomics, Biomedical Center Ludwig-Maximilians-University Munich, 80336 Munich, Germany; Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University Mainz, 55128 Mainz, Germany; Biochemistry and Molecular Biology Department, Faculty of Veterinary Medicine, Complutense University, Avenue Puerta de Hierro, 28040 Madrid, Spain
| | - Gianluca L Russo
- Physiological Genomics, Biomedical Center Ludwig-Maximilians-University Munich, 80336 Munich, Germany; Institute for Stem Cell Research, Helmholtz Center Munich, 85764 Neuherberg, Germany
| | - David Petrik
- Physiological Genomics, Biomedical Center Ludwig-Maximilians-University Munich, 80336 Munich, Germany; Institute for Stem Cell Research, Helmholtz Center Munich, 85764 Neuherberg, Germany
| | - Aditi Deshpande
- Physiological Genomics, Biomedical Center Ludwig-Maximilians-University Munich, 80336 Munich, Germany
| | - Christophe Heinrich
- Physiological Genomics, Biomedical Center Ludwig-Maximilians-University Munich, 80336 Munich, Germany
| | - Marisa Karow
- Physiological Genomics, Biomedical Center Ludwig-Maximilians-University Munich, 80336 Munich, Germany
| | - Stephen P Robertson
- Department of Women's and Children's Health, Dunedin School of Medicine, University of Otago, 9016 Dunedin, New Zealand
| | - Timm Schroeder
- Research Unit Stem Cell Dynamics, Helmholtz Center Munich, Neuherberg, 85764 Neuherberg, Germany
| | - Johannes Beckers
- German Center for Diabetes Research (DZD), 85764 Neuherberg, Germany; Institute of Experimental Genetics, Helmholtz Center Munich GmbH, 85764 Neuherberg, Germany; Center of Life and Food Sciences Weihenstephan, Technical University Munich, 85354 Freising, Germany
| | - Martin Irmler
- Institute of Experimental Genetics, Helmholtz Center Munich GmbH, 85764 Neuherberg, Germany
| | - Carsten Berndt
- Department of Neurology, Medical Faculty, Heinrich-Heine University Düsseldorf, Merowingerplatz 1a, 40225 Düsseldorf, Germany
| | | | - Marcus Conrad
- Institute of Developmental Genetics, Helmholtz Center Munich, 85764 Neuherberg, Germany
| | - Benedikt Berninger
- Physiological Genomics, Biomedical Center Ludwig-Maximilians-University Munich, 80336 Munich, Germany; Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University Mainz, 55128 Mainz, Germany; Focus Program Translational Neuroscience, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
| | - Magdalena Götz
- Physiological Genomics, Biomedical Center Ludwig-Maximilians-University Munich, 80336 Munich, Germany; Institute for Stem Cell Research, Helmholtz Center Munich, 85764 Neuherberg, Germany; Excellence Cluster of Systems Neurology (SYNERGY), 80336 Munich, Germany.
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127
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In Vivo Reprogramming for Brain and Spinal Cord Repair. eNeuro 2015; 2:eN-REV-0106-15. [PMID: 26730402 PMCID: PMC4699832 DOI: 10.1523/eneuro.0106-15.2015] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 10/01/2015] [Indexed: 01/14/2023] Open
Abstract
Cell reprogramming technologies have enabled the generation of various specific cell types including neurons from readily accessible patient cells, such as skin fibroblasts, providing an intriguing novel cell source for autologous cell transplantation. However, cell transplantation faces several difficult hurdles such as cell production and purification, long-term survival, and functional integration after transplantation. Recently, in vivo reprogramming, which makes use of endogenous cells for regeneration purpose, emerged as a new approach to circumvent cell transplantation. There has been evidence for in vivo reprogramming in the mouse pancreas, heart, and brain and spinal cord with various degrees of success. This mini review summarizes the latest developments presented in the first symposium on in vivo reprogramming glial cells into functional neurons in the brain and spinal cord, held at the 2014 annual meeting of the Society for Neuroscience in Washington, DC.
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128
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Bohrer C, Pfurr S, Mammadzada K, Schildge S, Plappert L, Hils M, Pous L, Rauch KS, Dumit VI, Pfeifer D, Dengjel J, Kirsch M, Schachtrup K, Schachtrup C. The balance of Id3 and E47 determines neural stem/precursor cell differentiation into astrocytes. EMBO J 2015; 34:2804-19. [PMID: 26438726 DOI: 10.15252/embj.201591118] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 08/17/2015] [Indexed: 12/14/2022] Open
Abstract
Adult neural stem/precursor cells (NSPCs) of the subventricular zone (SVZ) are an endogenous source for neuronal replacement in CNS disease. However, adult neurogenesis is compromised after brain injury in favor of a glial cell fate, which is mainly attributed to changes in the NSPC environment. Yet, it is unknown how this unfavorable extracellular environment translates into a transcriptional program altering NSPC differentiation. Here, we show that genetic depletion of the transcriptional regulator Id3 decreased the number of astrocytes generated from SVZ-derived adult NSPCs in the cortical lesion area after traumatic brain injury. Cortical brain injury resulted in rapid BMP-2 and Id3 up-regulation in the SVZ stem cell niche. Id3(-/-) adult NSPCs failed to differentiate into BMP-2-induced astrocytes, while NSPCs deficient for the Id3-controlled transcription factor E47 readily differentiated into astrocytes in the absence of BMP-2. Mechanistically, E47 repressed the expression of several astrocyte-specific genes in adult NSPCs. These results identify Id3 as the BMP-2-induced transcriptional regulator, promoting adult NSPC differentiation into astrocytes upon CNS injury and reveal a molecular link between environmental changes and NSPC differentiation in the CNS after injury.
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Affiliation(s)
- Christian Bohrer
- Institute of Anatomy and Cell Biology, University of Freiburg, Freiburg, Germany Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Sabrina Pfurr
- Institute of Anatomy and Cell Biology, University of Freiburg, Freiburg, Germany Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Könül Mammadzada
- Institute of Anatomy and Cell Biology, University of Freiburg, Freiburg, Germany Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Sebastian Schildge
- Institute of Anatomy and Cell Biology, University of Freiburg, Freiburg, Germany Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Leandra Plappert
- Institute of Anatomy and Cell Biology, University of Freiburg, Freiburg, Germany Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Miriam Hils
- Faculty of Biology, University of Freiburg, Freiburg, Germany Center for Chronic Immunodeficiency (CCI), University Medical Center Freiburg, University of Freiburg, Freiburg, Germany
| | - Lauriane Pous
- Institute of Anatomy and Cell Biology, University of Freiburg, Freiburg, Germany Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Katharina S Rauch
- Faculty of Biology, University of Freiburg, Freiburg, Germany Center for Chronic Immunodeficiency (CCI), University Medical Center Freiburg, University of Freiburg, Freiburg, Germany
| | - Verónica I Dumit
- Department of Dermatology, Medical Center, Freiburg Institute for Advanced Studies (FRIAS), ZBSA Center for Biological Systems Analysis, BIOSS Center for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Dietmar Pfeifer
- Department of Hematology, Oncology and Stem Cell Transplantation, University Medical Center Freiburg, University of Freiburg, Freiburg, Germany
| | - Jörn Dengjel
- Department of Dermatology, Medical Center, Freiburg Institute for Advanced Studies (FRIAS), ZBSA Center for Biological Systems Analysis, BIOSS Center for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Matthias Kirsch
- Institute of Anatomy and Cell Biology, University of Freiburg, Freiburg, Germany
| | - Kristina Schachtrup
- Center for Chronic Immunodeficiency (CCI), University Medical Center Freiburg, University of Freiburg, Freiburg, Germany
| | - Christian Schachtrup
- Institute of Anatomy and Cell Biology, University of Freiburg, Freiburg, Germany
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129
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Abstract
In vivo induction of non-neuronal cells into neurons by transcription factors offers potential therapeutic approaches for neural regeneration. Although generation of induced neuronal (iN) cells in vitro and in vivo has been reported, whether iN cells can be fully integrated into existing circuits remains unclear. Here we show that expression of achaete-scute complex homolog-like 1 (Ascl1) alone is sufficient to convert dorsal midbrain astrocytes of mice into functional iN cells in vitro and in vivo. Specific expression of Ascl1 in astrocytes by infection with GFAP-adeno-associated virus (AAV) vector converts astrocytes in dorsal midbrain, striatum, and somatosensory cortex of postnatal and adult mice into functional neurons in vivo. These iN cells mature progressively, exhibiting neuronal morphology and markers, action potentials, and synaptic inputs from and output to existing neurons. Thus, a single transcription factor, Ascl1, is sufficient to convert brain astrocytes into functional neurons, and GFAP-AAV is an efficient vector for generating iN cells from astrocytes in vivo.
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130
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Regeneration, Plasticity, and Induced Molecular Programs in Adult Zebrafish Brain. BIOMED RESEARCH INTERNATIONAL 2015; 2015:769763. [PMID: 26417601 PMCID: PMC4568348 DOI: 10.1155/2015/769763] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 09/25/2014] [Accepted: 09/25/2014] [Indexed: 12/20/2022]
Abstract
Regenerative capacity of the brain is a variable trait within animals. Aquatic vertebrates such as zebrafish have widespread ability to renew their brains upon damage, while mammals have—if not none—very limited overall regenerative competence. Underlying cause of such a disparity is not fully evident; however, one of the reasons could be activation of peculiar molecular programs, which might have specific roles after injury or damage, by the organisms that regenerate. If this hypothesis is correct, then there must be genes and pathways that (a) are expressed only after injury or damage in tissues, (b) are biologically and functionally relevant to restoration of neural tissue, and (c) are not detected in regenerating organisms. Presence of such programs might circumvent the initial detrimental effects of the damage and subsequently set up the stage for tissue redevelopment to take place by modulating the plasticity of the neural stem/progenitor cells. Additionally, if transferable, those “molecular mechanisms of regeneration” could open up new avenues for regenerative therapies of humans in clinical settings. This review focuses on the recent studies addressing injury/damage-induced molecular programs in zebrafish brain, underscoring the possibility of the presence of genes that could be used as biomarkers of neural plasticity and regeneration.
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131
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Péron S, Berninger B. Reawakening the sleeping beauty in the adult brain: neurogenesis from parenchymal glia. Curr Opin Genet Dev 2015; 34:46-53. [PMID: 26296150 DOI: 10.1016/j.gde.2015.07.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 07/19/2015] [Indexed: 12/12/2022]
Abstract
Life-long neurogenesis is highly restricted to specialized niches in the adult mammalian brain and therefore the brain's capacity for spontaneous regeneration is extremely limited. However, recent work has demonstrated that under certain circumstances parenchymal astrocytes and NG2 glia can generate neuronal progeny. In the striatum, stroke or excitotoxic lesions can reawaken in astrocytes a latent neurogenic program resulting in the genesis of new neurons. By contrast, in brain areas that fail to mount a neurogenic response following injury, such as the cerebral cortex, forced expression of neurogenic reprogramming factors can lineage convert local glia into induced neurons. Yet, injury-induced and reprogramming-induced neurogenesis exhibit intriguing commonalities, suggesting that they may converge on similar mechanisms.
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Affiliation(s)
- Sophie Péron
- Laboratory "Adult Neurogenesis and Cellular Reprogramming", Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University Mainz, Hanns-Dieter-Hüsch Weg 19, D-55128 Mainz, Germany; Focus Program Translational Neuroscience, Johannes Gutenberg University Mainz, Langenbeckstrasse 1, D-55131 Mainz, Germany
| | - Benedikt Berninger
- Laboratory "Adult Neurogenesis and Cellular Reprogramming", Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University Mainz, Hanns-Dieter-Hüsch Weg 19, D-55128 Mainz, Germany; Focus Program Translational Neuroscience, Johannes Gutenberg University Mainz, Langenbeckstrasse 1, D-55131 Mainz, Germany.
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132
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Salgado AJ, Sousa JC, Costa BM, Pires AO, Mateus-Pinheiro A, Teixeira FG, Pinto L, Sousa N. Mesenchymal stem cells secretome as a modulator of the neurogenic niche: basic insights and therapeutic opportunities. Front Cell Neurosci 2015. [PMID: 26217178 PMCID: PMC4499760 DOI: 10.3389/fncel.2015.00249] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Neural stem cells (NSCs) and mesenchymal stem cells (MSCs) share few characteristics apart from self-renewal and multipotency. In fact, the neurogenic and osteogenic stem cell niches derive from two distinct embryonary structures; while the later originates from the mesoderm, as all the connective tissues do, the first derives from the ectoderm. Therefore, it is highly unlikely that stem cells isolated from one niche could form terminally differentiated cells from the other. Additionally, these two niches are associated to tissues/systems (e.g., bone and central nervous system) that have markedly different needs and display diverse functions within the human body. Nevertheless they do share common features. For instance, the differentiation of both NSCs and MSCs is intimately associated with the bone morphogenetic protein family. Moreover, both NSCs and MSCs secrete a panel of common growth factors, such as nerve growth factor (NGF), glial derived neurotrophic factor (GDNF), and brain derived neurotrophic factor (BDNF), among others. But it is not the features they share but the interaction between them that seem most important, and worth exploring; namely, it has already been shown that there are mutually beneficially effects when these cell types are co-cultured in vitro. In fact the use of MSCs, and their secretome, become a strong candidate to be used as a therapeutic tool for CNS applications, namely by triggering the endogenous proliferation and differentiation of neural progenitors, among other mechanisms. Quite interestingly it was recently revealed that MSCs could be found in the human brain, in the vicinity of capillaries. In the present review we highlight how MSCs and NSCs in the neurogenic niches interact. Furthermore, we propose directions on this field and explore the future therapeutic possibilities that may arise from the combination/interaction of MSCs and NSCs.
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Affiliation(s)
- Antonio J Salgado
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho Braga, Portugal ; ICVS/3B's, PT Government Associate Laboratory Braga/Guimarães, Portugal
| | - Joao C Sousa
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho Braga, Portugal ; ICVS/3B's, PT Government Associate Laboratory Braga/Guimarães, Portugal
| | - Bruno M Costa
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho Braga, Portugal ; ICVS/3B's, PT Government Associate Laboratory Braga/Guimarães, Portugal
| | - Ana O Pires
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho Braga, Portugal ; ICVS/3B's, PT Government Associate Laboratory Braga/Guimarães, Portugal
| | - António Mateus-Pinheiro
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho Braga, Portugal ; ICVS/3B's, PT Government Associate Laboratory Braga/Guimarães, Portugal
| | - F G Teixeira
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho Braga, Portugal ; ICVS/3B's, PT Government Associate Laboratory Braga/Guimarães, Portugal
| | - Luisa Pinto
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho Braga, Portugal ; ICVS/3B's, PT Government Associate Laboratory Braga/Guimarães, Portugal
| | - Nuno Sousa
- Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho Braga, Portugal ; ICVS/3B's, PT Government Associate Laboratory Braga/Guimarães, Portugal
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133
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The Neurogenic Potential of Astrocytes Is Regulated by Inflammatory Signals. Mol Neurobiol 2015; 53:3724-3739. [PMID: 26138449 PMCID: PMC4937102 DOI: 10.1007/s12035-015-9296-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 06/08/2015] [Indexed: 01/01/2023]
Abstract
Although the adult brain contains neural stem cells (NSCs) that generate new neurons throughout life, these astrocyte-like populations are restricted to two discrete niches. Despite their terminally differentiated phenotype, adult parenchymal astrocytes can re-acquire NSC-like characteristics following injury, and as such, these ‘reactive’ astrocytes offer an alternative source of cells for central nervous system (CNS) repair following injury or disease. At present, the mechanisms that regulate the potential of different types of astrocytes are poorly understood. We used in vitro and ex vivo astrocytes to identify candidate pathways important for regulation of astrocyte potential. Using in vitro neural progenitor cell (NPC)-derived astrocytes, we found that exposure of more lineage-restricted astrocytes to either tumor necrosis factor alpha (TNF-α) (via nuclear factor-κB (NFκB)) or the bone morphogenetic protein (BMP) inhibitor, noggin, led to re-acquisition of NPC properties accompanied by transcriptomic and epigenetic changes consistent with a more neurogenic, NPC-like state. Comparative analyses of microarray data from in vitro-derived and ex vivo postnatal parenchymal astrocytes identified several common pathways and upstream regulators associated with inflammation (including transforming growth factor (TGF)-β1 and peroxisome proliferator-activated receptor gamma (PPARγ)) and cell cycle control (including TP53) as candidate regulators of astrocyte phenotype and potential. We propose that inflammatory signalling may control the normal, progressive restriction in potential of differentiating astrocytes as well as under reactive conditions and represent future targets for therapies to harness the latent neurogenic capacity of parenchymal astrocytes.
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134
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Akhtar AA, Breunig JJ. Lost highway(s): barriers to postnatal cortical neurogenesis and implications for brain repair. Front Cell Neurosci 2015; 9:216. [PMID: 26136658 PMCID: PMC4468390 DOI: 10.3389/fncel.2015.00216] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Accepted: 05/21/2015] [Indexed: 11/13/2022] Open
Abstract
The genesis of the cerebral cortex is a highly complex and tightly-orchestrated process of cell division, migration, maturation, and integration. Developmental missteps often have catastrophic consequences on cortical function. Further, the cerebral cortex, in which neurogenesis takes place almost exclusively prenatally, has a very poor capacity for replacement of neurons lost to injury or disease. A multitude of factors underlie this deficit, including the depletion of radial glia, the gliogenic switch which mitigates continued neurogenesis, diminished neuronal migratory streams, and inflammatory processes associated with disease. Despite this, there are glimmers of hope that new approaches may allow for more significant cortical repair. Herein, we review corticogenesis from the context of regeneration and detail the strategies to promote neurogenesis, including interneuron transplants and glial reprogramming. Such strategies circumvent the "lost highways" which are critical for cortical development but are absent in the adult. These new approaches may provide for the possibility of meaningful clinical regeneration of elements of cortical circuitry lost to trauma and disease.
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Affiliation(s)
- Aslam Abbasi Akhtar
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center Los Angeles, CA, USA ; Department of Biomedical Sciences, Cedars-Sinai Medical Center Los Angeles, CA, USA
| | - Joshua J Breunig
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center Los Angeles, CA, USA ; Department of Biomedical Sciences, Cedars-Sinai Medical Center Los Angeles, CA, USA ; Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center Los Angeles, CA, USA
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135
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Impact of traumatic brain injury on sleep structure, electrocorticographic activity and transcriptome in mice. Brain Behav Immun 2015; 47:118-30. [PMID: 25576803 DOI: 10.1016/j.bbi.2014.12.023] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 12/22/2014] [Accepted: 12/22/2014] [Indexed: 12/21/2022] Open
Abstract
Traumatic brain injury (TBI), including mild TBI (mTBI), is importantly associated with vigilance and sleep complaints. Because sleep is required for learning, plasticity and recovery, we here evaluated the bidirectional relationship between mTBI and sleep with two specific objectives: (1) Test that mTBI rapidly impairs sleep-wake architecture and the dynamics of the electrophysiological marker of sleep homeostasis (i.e., non-rapid eye movement sleep delta (1-4Hz) activity); (2) evaluate the impact of sleep loss following mTBI on the expression of plasticity markers that have been linked to sleep homeostasis and on genome-wide gene expression. A closed-head injury model was used to perform a 48h electrocorticographic (ECoG) recording in mice submitted to mTBI or Sham surgery. mTBI was found to immediately decrease the capacity to sustain long bouts of wakefulness as well as the amplitude of the time course of ECoG delta activity during wakefulness. Significant changes in ECoG spectral activity during wakefulness, non-rapid eye movement and rapid eye movement sleep were observed mainly on the second recorded day. A second experiment was performed to measure gene expression in the cerebral cortex and hippocampus after a mTBI followed either by two consecutive days of 6h sleep deprivation (SD) or of undisturbed behavior (quantitative PCR and next-generation sequencing). mTBI modified the expression of genes involved in immunity, inflammation and glial function (e.g., chemokines, glial markers) and SD changed that of genes linked to circadian rhythms, synaptic activity/neuronal plasticity, neuroprotection and cell death and survival. SD appeared to affect gene expression in the cerebral cortex more importantly after mTBI than Sham surgery including that of the astrocytic marker Gfap, which was proposed as a marker of clinical outcome after TBI. Interestingly, SD impacted the hippocampal expression of the plasticity elements Arc and EfnA3 only after mTBI. Overall, our findings reveal alterations in spectral signature across all vigilance states in the first days after mTBI, and show that sleep loss post-mTBI reprograms the transcriptome in a brain area-specific manner and in a way that could be deleterious to brain recovery.
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136
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Sakry D, Trotter J. The role of the NG2 proteoglycan in OPC and CNS network function. Brain Res 2015; 1638:161-166. [PMID: 26100334 DOI: 10.1016/j.brainres.2015.06.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 05/27/2015] [Accepted: 06/02/2015] [Indexed: 01/13/2023]
Abstract
In the normal mammalian CNS, the NG2 proteoglycan is expressed by oligodendrocyte precursor cells (OPC) but not by any other neural cell-type. NG2 is a type-1 membrane protein, exerting multiple roles in the CNS including intracellular signaling within the OPC, with effects on migration, cytoskeleton interaction and target gene regulation. It has been recently shown that the extracellular region of NG2, in addition to an adhesive function, acts as a soluble ECM component with the capacity to alter defined neuronal network properties. This region of NG2 is thus endowed with neuromodulatory properties. In order to generate biologically active fragments yielding these properties, the sequential cleavage of the NG2 protein by α- and γ-secretases occurs. The basal level of constitutive cleavage is stimulated by neuronal network activity. This processing leads to 4 major NG2 fragments which all have been associated with distinct biological functions. Here we summarize these functions, focusing on recent discoveries and their implications for the CNS. This article is part of a Special Issue entitled SI:NG2-glia(Invited only).
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Affiliation(s)
- Dominik Sakry
- Institute of Molecular Cell Biology; Johannes Gutenberg University of Mainz, Mainz, Germany.
| | - Jacqueline Trotter
- Institute of Molecular Cell Biology; Johannes Gutenberg University of Mainz, Mainz, Germany.
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137
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Dimou L, Gallo V. NG2-glia and their functions in the central nervous system. Glia 2015; 63:1429-51. [PMID: 26010717 DOI: 10.1002/glia.22859] [Citation(s) in RCA: 173] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 05/04/2015] [Indexed: 12/12/2022]
Abstract
In the central nervous system, NG2-glia represent a neural cell population that is distinct from neurons, astrocytes, and oligodendrocytes. While in the past the main role ascribed to these cells was that of progenitors for oligodendrocytes, in the last years it has become more obvious that they have further functions in the brain. Here, we will discuss some of the most current and highly debated issues regarding NG2-glia: Do these cells represent a heterogeneous population? Can they give rise to different progenies, and does this change under pathological conditions? How do they respond to injury or pathology? What is the role of neurotransmitter signaling between neurons and NG2-glia? We will first give an overview on the developmental origin of NG2-glia, and then discuss whether their distinct properties in different brain regions are the result of environmental influences, or due to intrinsic differences. We will then review and discuss their in vitro differentiation potential and in vivo lineage under physiological and pathological conditions, together with their electrophysiological properties in distinct brain regions and at different developmental stages. Finally, we will focus on their potential to be used as therapeutic targets in demyelinating and neurodegenerative diseases. Therefore, this review article will highlight the importance of NG2-glia not only in the healthy, but also in the diseased brain.
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Affiliation(s)
- L Dimou
- Physiological Genomics, Biomedical Center, Ludwig-Maximilians University, Munich, 80336, Germany.,Institute for Stem Cell Research, Helmholtz Zentrum Munich, Neuherberg, 85764, Germany
| | - V Gallo
- Center for Neuroscience Research, Children's Research Institute, Children's National Medical Center, Washington, District of Columbia
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138
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Dametti S, Faravelli I, Ruggieri M, Ramirez A, Nizzardo M, Corti S. Experimental Advances Towards Neural Regeneration from Induced Stem Cells to Direct In Vivo Reprogramming. Mol Neurobiol 2015; 53:2124-31. [PMID: 25934102 DOI: 10.1007/s12035-015-9181-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Accepted: 04/15/2015] [Indexed: 10/23/2022]
Abstract
Neuronal loss is a common substrate of many neurological diseases that still lack effective treatments and highly burden lives of affected individuals. The discovery of self-renewing stem cells within the central nervous system (CNS) has opened the doors to the possibility of using the plasticity of CNS as a potential strategy for the development of regenerative therapies after injuries. The role of neural progenitor cells appears to be crucial, but insufficient in reparative processes after damage. In addition, the mechanisms that regulate these events are still largely unknown. Stem cell-based therapeutic approaches have primarily focused on the use of either induced pluripotent stem cells or induced neural stem cells as sources for cell transplantation. More recently, in vivo direct reprogramming of endogenous CNS cells into multipotent neural stem/progenitor cells has been proposed as an alternative strategy that could overcome the limits connected with both the invasiveness of exogenous cell transplantation and the technical issues of in vitro reprogramming (i.e., the time requested and the limited available amount of directly induced neuronal cells). In this review, we aim to highlight the recent studies on in vivo direct reprogramming, focusing on astrocytes conversion to neurons or to neural stem/precursors cells, in the perspective of future therapeutic purposes for neurological disorders.
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Affiliation(s)
- Sara Dametti
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Irene Faravelli
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Margherita Ruggieri
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Agnese Ramirez
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Monica Nizzardo
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Stefania Corti
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), Neurology Unit, IRCCS Foundation Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Via Francesco Sforza 35, 20122, Milan, Italy.
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139
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Heinrich C, Spagnoli FM, Berninger B. In vivo reprogramming for tissue repair. Nat Cell Biol 2015; 17:204-11. [PMID: 25720960 DOI: 10.1038/ncb3108] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Vital organs such as the pancreas and the brain lack the capacity for effective regeneration. To overcome this limitation, an emerging strategy consists of converting resident tissue-specific cells into the cell types that are lost due to disease by a process called in vivo lineage reprogramming. Here we discuss recent breakthroughs in regenerating pancreatic β-cells and neurons from various cell types, and highlight fundamental challenges that need to be overcome for the translation of in vivo lineage reprogramming into therapy.
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Affiliation(s)
- Christophe Heinrich
- INSERM U836, F-38000 Grenoble, France and Univ. Grenoble Alpes, Grenoble Institut des Neurosciences, GIN, F-38000 Grenoble, France
| | | | - Benedikt Berninger
- Institute of Physiological Chemistry and the Focus Program Translational Neuroscience, University Medical Center of the Johannes Gutenberg University Mainz, D-55128 Mainz, Germany, and Physiological Genomics, Institute of Physiology, Ludwig Maximilians University Munich, D-80336 Munich, Germany
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140
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Decoding astrocyte heterogeneity: New tools for clonal analysis. Neuroscience 2015; 323:10-9. [PMID: 25917835 DOI: 10.1016/j.neuroscience.2015.04.036] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 04/03/2015] [Accepted: 04/15/2015] [Indexed: 12/11/2022]
Abstract
The importance of astrocyte heterogeneity came out as a hot topic in neurosciences especially over the last decades, when the development of new methodologies allowed demonstrating the existence of big differences in morphological, neurochemical and physiological features between astrocytes. However, although the knowledge about the biology of astrocytes is increasing rapidly, an important characteristic that remained unexplored, until the last years, has been the relationship between astrocyte lineages and cell heterogeneity. To fill this gap, a new method called StarTrack was recently developed, a powerful genetic tool that allows tracking astrocyte lineages forming cell clones. Using StarTrack, a single astrocyte progenitor and its progeny can be specifically labeled from its generation, during embryonic development, to its final fate in the adult brain. Because of this specific labeling, astrocyte clones, exhibiting heterogeneous morphologies and features, can be easily analyzed in relation to their ontogenetic origin. This review summarizes how astrocyte heterogeneity can be decoded studying the embryonic development of astrocyte lineages and their clonal relationship. Finally, we discuss about some of the challenges and opportunities emerging in this exciting area of investigation.
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141
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Therapeutical Strategies for Spinal Cord Injury and a Promising Autologous Astrocyte-Based Therapy Using Efficient Reprogramming Techniques. Mol Neurobiol 2015; 53:2826-2842. [DOI: 10.1007/s12035-015-9157-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 03/19/2015] [Indexed: 01/01/2023]
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142
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Oligodendrocyte birth and death following traumatic brain injury in adult mice. PLoS One 2015; 10:e0121541. [PMID: 25798924 PMCID: PMC4370677 DOI: 10.1371/journal.pone.0121541] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 02/03/2015] [Indexed: 12/13/2022] Open
Abstract
Oligodendrocytes are responsible for producing and maintaining myelin throughout the CNS. One of the pathological features observed following traumatic brain injury (TBI) is the progressive demyelination and degeneration of axons within white matter tracts. While the effect of TBI on axonal health has been well documented, there is limited information regarding the response of oligodendrocytes within these areas. The aim of this study was to characterize the response of both mature oligodendrocytes and immature proliferative oligodendrocyte lineage cells across a 3 month timecourse following TBI. A computer-controlled cortical impact model was used to produce a focal lesion in the left motor cortex of adult mice. Immunohistochemical analyses were performed at 48 hours, 7 days, 2 weeks, 5 weeks and 3 months following injury to assess the prevalence of mature CC-1+ oligodendrocyte cell death, immature Olig2+ cell proliferation and longer term survival in the corpus callosum and external capsule. Decreased CC-1 immunoreactivity was observed in white matter adjacent to the site of injury from 2 days to 2 weeks post TBI, with ongoing mature oligodendrocyte apoptosis after this time. Conversely, proliferation of Olig2+ cells was observed as early as 48 hours post TBI and significant numbers of these cells and their progeny survived and remained in the external capsule within the injured hemisphere until at least 3 months post injury. These findings demonstrate that immature oligodendrocyte lineage cells respond to TBI by replacing oligodendrocytes lost due to damage and that this process occurs for months after injury.
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143
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Liu W, Zhou H, Liu L, Zhao C, Deng Y, Chen L, Wu L, Mandrycky N, McNabb CT, Peng Y, Fuchs PN, Lu J, Sheen V, Qiu M, Mao M, Lu QR. Disruption of neurogenesis and cortical development in transgenic mice misexpressing Olig2, a gene in the Down syndrome critical region. Neurobiol Dis 2015; 77:106-16. [PMID: 25747816 DOI: 10.1016/j.nbd.2015.02.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 02/08/2015] [Accepted: 02/24/2015] [Indexed: 12/15/2022] Open
Abstract
The basic helix-loop-helix (bHLH) transcription factor Olig2 is crucial for mammalian central nervous system development. Human ortholog OLIG2 is located in the Down syndrome critical region in trisomy 21. To investigate the effect of Olig2 misexpression on brain development, we generated a developmentally regulated Olig2-overexpressing transgenic line with a Cre/loxP system. The transgenic mice with Olig2 misexpression in cortical neural stem/progenitor cells exhibited microcephaly, cortical dyslamination, hippocampus malformation, and profound motor deficits. Ectopic misexpression of Olig2 impaired cortical progenitor proliferation and caused precocious cell cycle exit. Massive neuronal cell death was detected in the developing cortex of Olig2-misexpressing mice. In addition, Olig2 misexpression led to a significant downregulation of neuronal specification factors including Ngn1, Ngn2 and Pax6, and a defect in cortical neurogenesis. Chromatin-immunoprecipitation and sequencing (ChIP-Seq) analysis indicates that Olig2 directly targets the promoter and/or enhancer regions of Nfatc4, Dscr1/Rcan1 and Dyrk1a, the critical neurogenic genes that contribute to Down syndrome phenotypes, and inhibits their expression. Together, our study suggests that Olig2 misexpression in neural stem cells elicits neurogenesis defects and neuronal cell death, which may contribute to developmental disorders including Down syndrome, where OLIG2 is triplicated on chromosomal 21.
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Affiliation(s)
- Wei Liu
- Department of Pediatrics, West China Second Hospital, Sichuan University, Chengdu, 610041, PR China; Department of Pediatrics, Brain Tumor Center, Division of Experimental Hematology and Cancer Biology, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 25229, USA; Key Laboratory of Obstetrics & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second Hospital, Sichuan University, Chengdu, 610041, PR China
| | - Hui Zhou
- Department of Pediatrics, West China Second Hospital, Sichuan University, Chengdu, 610041, PR China
| | - Lei Liu
- Department of Pediatrics, West China Second Hospital, Sichuan University, Chengdu, 610041, PR China
| | - Chuntao Zhao
- Department of Pediatrics, Brain Tumor Center, Division of Experimental Hematology and Cancer Biology, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 25229, USA
| | - Yaqi Deng
- Department of Pediatrics, Brain Tumor Center, Division of Experimental Hematology and Cancer Biology, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 25229, USA
| | - Lina Chen
- Department of Pediatrics, West China Second Hospital, Sichuan University, Chengdu, 610041, PR China
| | - Laiman Wu
- Department of Pediatrics, Brain Tumor Center, Division of Experimental Hematology and Cancer Biology, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 25229, USA
| | - Nicole Mandrycky
- Department of Developmental Biology, University of Texas Southwestern Medical Center, TX 75390, USA
| | | | - Yuanbo Peng
- Department of Psychology, University of Texas, Arlington, TX 76019, USA
| | - Perry N Fuchs
- Department of Psychology, University of Texas, Arlington, TX 76019, USA
| | - Jie Lu
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Volney Sheen
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Mengsheng Qiu
- Institute of Developmental and Regenerative Biology, Key Laboratory of Organ Development and Regeneration of Zhejiang Province, College of Life Sciences, Hangzhou Normal University, Hangzhou, 310029, PR China; Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, KY 40292, USA
| | - Meng Mao
- Department of Pediatrics, West China Second Hospital, Sichuan University, Chengdu, 610041, PR China; Key Laboratory of Obstetrics & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second Hospital, Sichuan University, Chengdu, 610041, PR China
| | - Q Richard Lu
- Department of Pediatrics, Brain Tumor Center, Division of Experimental Hematology and Cancer Biology, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 25229, USA; Key Laboratory of Obstetrics & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second Hospital, Sichuan University, Chengdu, 610041, PR China; Key Laboratory of Birth Defects, Children's Hospital of Fudan University, Shanghai, 201102, PR China.
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144
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Zaky AZ, Moftah MZ. Neurogenesis and growth factors expression after complete spinal cord transection in Pleurodeles waltlii. Front Cell Neurosci 2015; 8:458. [PMID: 25628538 PMCID: PMC4292736 DOI: 10.3389/fncel.2014.00458] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 12/16/2014] [Indexed: 01/24/2023] Open
Abstract
Following spinal lesion, connections between the supra-spinal centers and spinal neuronal networks can be disturbed, which causes the deterioration or even the complete absence of sublesional locomotor activity. In mammals, possibilities of locomotion restoration are much reduced since descending tracts either have very poor regenerative ability or do not regenerate at all. However, in lower vertebrates, there is spontaneous locomotion recuperation after complete spinal cord transection at the mid-trunk level. This phenomenon depends on a translesional descending axon re-growth originating from the brainstem. On the other hand, cellular and molecular mechanisms underlying spinal cord regeneration and in parallel, locomotion restoration of the animal, are not well known. Fibroblast growth factor 2 (FGF-2) plays an important role in different processes such as neural induction, neuronal progenitor proliferation and their differentiation. Studies had shown an over expression of this growth factor after tail amputation. Nestin, a protein specific for intermediate filaments, is considered an early marker for neuronal precursors. It has been recently shown that its expression increases after tail transection in urodeles. Using this marker and western blots, our results show that the number of FGF-2 and FGFR2 mRNAs increases and is correlated with an increase in neurogenesis especially in the central canal lining cells immediately after lesion. This study also confirms that spinal cord re-growth through the lesion site initially follows a rostrocaudal direction. In addition to its role known in neuronal differentiation, FGF-2 could be implicated in the differentiation of ependymal cells into neuronal progenitors.
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Affiliation(s)
- Amira Z Zaky
- Biochemistry Department, Faculty of Science, Alexandria University Alexandria, Egypt
| | - Marie Z Moftah
- Zoology Department, Faculty of Science, Alexandria University Alexandria, Egypt
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145
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Somkuwar SS, Staples MC, Galinato MH, Fannon MJ, Mandyam CD. Role of NG2 expressing cells in addiction: a new approach for an old problem. Front Pharmacol 2014; 5:279. [PMID: 25566075 PMCID: PMC4271769 DOI: 10.3389/fphar.2014.00279] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 11/30/2014] [Indexed: 12/17/2022] Open
Abstract
Neuron-glial antigen 2 (NG2) is a proteoglycan expressed predominantly in oligodendrocyte progenitor cells (OPCs). NG2-expressing OPCs (NG2-OPCs) are self-renewing cells that are widely distributed in the gray and white matter areas of the central nervous system. NG2-OPCs can mature into premyelinating oligodendrocytes and myelinating oligodendroglia which serve as the primary source of myelin in the brain. This review characterizes NG2-OPCs in brain structure and function, conceptualizes the role of NG2-OPCs in brain regions associated with negative reinforcement and relapse to drug seeking and discusses how NG2-OPCs are regulated by neuromodulators linked to motivational withdrawal. We hope to provide the readers with an overview of the role of NG2-OPCs in brain structure and function in the context of negative affect state in substance abuse disorders and to integrate our current understanding of the physiological significance of the NG2-OPCs in the adult brain.
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Affiliation(s)
- Sucharita S Somkuwar
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute La Jolla, CA, USA
| | - Miranda C Staples
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute La Jolla, CA, USA
| | - Melissa H Galinato
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute La Jolla, CA, USA
| | - McKenzie J Fannon
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute La Jolla, CA, USA
| | - Chitra D Mandyam
- Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute La Jolla, CA, USA
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146
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147
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Huang S, Tang C, Sun S, Cao W, Qi W, Xu J, Huang J, Lu W, Liu Q, Gong B, Zhang Y, Jiang J. Protective Effect of Electroacupuncture on Neural Myelin Sheaths is Mediated via Promotion of Oligodendrocyte Proliferation and Inhibition of Oligodendrocyte Death After Compressed Spinal Cord Injury. Mol Neurobiol 2014; 52:1870-1881. [PMID: 25465241 DOI: 10.1007/s12035-014-9022-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 10/24/2014] [Indexed: 01/05/2023]
Abstract
Electroacupuncture (EA) has been used worldwide to treat demyelinating diseases, but its therapeutic mechanism is poorly understood. In this study, a custom-designed model of compressed spinal cord injury (CSCI) was used to induce demyelination. Zusanli (ST36) and Taixi (KI3) acupoints of adult rats were stimulated by EA to demonstrate its protective effect. At 14 days after EA, both locomotor skills and ultrastructural features of myelin sheath were significantly improved. Phenotypes of proliferating cells were identified by double immunolabeling of 5-ethynyl-2'-deoxyuridine with antibodies to cell markers: NG2 [oligodendrocyte precursor cell (OPC) marker], 2',3'-cyclic-nucleotide 3'-phosphodiesterase (CNPase) (oligodendrocyte marker), and glial fibrillary acidic protein (GFAP) (astrocyte marker). EA enhanced the proliferation of OPCs and CNPase, as well as the differentiation of OPCs by promoting Olig2 (the basic helix-loop-helix protein) and attenuating Id2 (the inhibitor of DNA binding 2). EA could also improve myelin basic protein (MBP) and protect existing oligodendrocytes from apoptosis by inhibiting caspase-12 (a representative of endoplasmic reticulum stress) and cytochrome c (an apoptotic factor and hallmark of mitochondria). Therefore, our results indicate that the protective effect of EA on neural myelin sheaths is mediated via promotion of oligodendrocyte proliferation and inhibition of oligodendrocyte death after CSCI.
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Affiliation(s)
- Siqin Huang
- Traditional Chinese Medicine College, Chongqing Medical University, No.1 Medical College Road, Yuzhong District, Chongqing, 400016, China.,Institute of Neuroscience, Chongqing Medical University, No.1 Medical College Road, Yuzhong District, Chongqing, 400016, China
| | - Chenglin Tang
- Traditional Chinese Medicine College, Chongqing Medical University, No.1 Medical College Road, Yuzhong District, Chongqing, 400016, China
| | - Shanquan Sun
- Institute of Neuroscience, Chongqing Medical University, No.1 Medical College Road, Yuzhong District, Chongqing, 400016, China.
| | - Wenfu Cao
- Traditional Chinese Medicine College, Chongqing Medical University, No.1 Medical College Road, Yuzhong District, Chongqing, 400016, China
| | - Wei Qi
- Chongqing Three Gorgers Central Hospital, No.165 Xin Cheng Road, Wanzhou District, Chongqing, 400000, China
| | - Jin Xu
- Institute of Neuroscience, Chongqing Medical University, No.1 Medical College Road, Yuzhong District, Chongqing, 400016, China
| | - Juan Huang
- Institute of Neuroscience, Chongqing Medical University, No.1 Medical College Road, Yuzhong District, Chongqing, 400016, China
| | - Weitian Lu
- Institute of Neuroscience, Chongqing Medical University, No.1 Medical College Road, Yuzhong District, Chongqing, 400016, China
| | - Qian Liu
- Institute of Neuroscience, Chongqing Medical University, No.1 Medical College Road, Yuzhong District, Chongqing, 400016, China
| | - Biao Gong
- Traditional Chinese Medicine College, Chongqing Medical University, No.1 Medical College Road, Yuzhong District, Chongqing, 400016, China
| | - Yi Zhang
- Traditional Chinese Medicine College, Chongqing Medical University, No.1 Medical College Road, Yuzhong District, Chongqing, 400016, China
| | - Jin Jiang
- Institute of Neuroscience, Chongqing Medical University, No.1 Medical College Road, Yuzhong District, Chongqing, 400016, China
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148
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How to make neurons--thoughts on the molecular logic of neurogenesis in the central nervous system. Cell Tissue Res 2014; 359:5-16. [PMID: 25416507 DOI: 10.1007/s00441-014-2048-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 10/23/2014] [Indexed: 12/20/2022]
Abstract
Neuronal differentiation relies on a set of interconnected molecular events to achieve the differentiation of pan-neuronal hallmarks, together with neuronal subtype-specific features. Here, we propose a conceptual framework for these events, based on recent findings. This framework encompasses a dimension in time during development, progressing from early master regulators to later expressed effector genes and terminal selector genes. As a horizontal intersection, we propose the action of permissive fate determinants that are critical in allowing progression through the above transcriptional phases. Typically, these are widely expressed and often interact with the chromatin remodeling machinery. We conclude by discussing this model in the context of the direct fate conversion of various somatic cells into neurons.
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149
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Heinrich C, Bergami M, Gascón S, Lepier A, Viganò F, Dimou L, Sutor B, Berninger B, Götz M. Sox2-mediated conversion of NG2 glia into induced neurons in the injured adult cerebral cortex. Stem Cell Reports 2014; 3:1000-14. [PMID: 25458895 PMCID: PMC4264057 DOI: 10.1016/j.stemcr.2014.10.007] [Citation(s) in RCA: 231] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 10/16/2014] [Accepted: 10/16/2014] [Indexed: 02/07/2023] Open
Abstract
The adult cerebral cortex lacks the capacity to replace degenerated neurons following traumatic injury. Conversion of nonneuronal cells into induced neurons has been proposed as an innovative strategy toward brain repair. Here, we show that retrovirus-mediated expression of the transcription factors Sox2 and Ascl1, but strikingly also Sox2 alone, can induce the conversion of genetically fate-mapped NG2 glia into induced doublecortin (DCX)+ neurons in the adult mouse cerebral cortex following stab wound injury in vivo. In contrast, lentiviral expression of Sox2 in the unlesioned cortex failed to convert oligodendroglial and astroglial cells into DCX+ cells. Neurons induced following injury mature morphologically and some acquire NeuN while losing DCX. Patch-clamp recording of slices containing Sox2- and/or Ascl1-transduced cells revealed that a substantial fraction of these cells receive synaptic inputs from neurons neighboring the injury site. Thus, NG2 glia represent a potential target for reprogramming strategies toward cortical repair. Sox2 or Sox2/Ascl1 can convert glia into induced DCX+ neurons in the injured cortex Sox10-iCreERT2-mediated fate mapping shows that induced neurons are NG2 glia derived Induced neurons receive (or retain) synapses from preexisting neurons Without prior injury, Sox2 does not convert cortical macroglia into neurons
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Affiliation(s)
- Christophe Heinrich
- Physiological Genomics, Institute of Physiology, Ludwig-Maximilians University Munich, 80336 Munich, Germany; INSERM U836, University Grenoble Alpes, Grenoble Institute of Neurosciences, 38000 Grenoble, France
| | - Matteo Bergami
- Physiological Genomics, Institute of Physiology, Ludwig-Maximilians University Munich, 80336 Munich, Germany
| | - Sergio Gascón
- Physiological Genomics, Institute of Physiology, Ludwig-Maximilians University Munich, 80336 Munich, Germany; Institute for Stem Cell Research, National Research Center for Environment and Health, 85764 Neuherberg, Germany
| | - Alexandra Lepier
- Physiological Genomics, Institute of Physiology, Ludwig-Maximilians University Munich, 80336 Munich, Germany
| | - Francesca Viganò
- Physiological Genomics, Institute of Physiology, Ludwig-Maximilians University Munich, 80336 Munich, Germany
| | - Leda Dimou
- Physiological Genomics, Institute of Physiology, Ludwig-Maximilians University Munich, 80336 Munich, Germany; Institute for Stem Cell Research, National Research Center for Environment and Health, 85764 Neuherberg, Germany
| | - Bernd Sutor
- Physiological Genomics, Institute of Physiology, Ludwig-Maximilians University Munich, 80336 Munich, Germany
| | - Benedikt Berninger
- Physiological Genomics, Institute of Physiology, Ludwig-Maximilians University Munich, 80336 Munich, Germany; Institute of Physiological Chemistry, University Medical Center, Johannes Gutenberg University Mainz, 55128 Mainz, Germany; Focus Program Translational Neuroscience, Johannes Gutenberg University Mainz, 55131 Mainz, Germany.
| | - Magdalena Götz
- Physiological Genomics, Institute of Physiology, Ludwig-Maximilians University Munich, 80336 Munich, Germany; Institute for Stem Cell Research, National Research Center for Environment and Health, 85764 Neuherberg, Germany; Munich Cluster for Systems Neurology (SyNergy), 80336 Munich, Germany.
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150
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Verwer RWH, Sluiter AA, Balesar RA, Baaijen JC, de Witt Hamer PC, Speijer D, Li Y, Swaab DF. Injury Response of Resected Human Brain Tissue In Vitro. Brain Pathol 2014; 25:454-68. [PMID: 25138544 DOI: 10.1111/bpa.12189] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 08/06/2014] [Indexed: 12/19/2022] Open
Abstract
Brain injury affects a significant number of people each year. Organotypic cultures from resected normal neocortical tissue provide unique opportunities to study the cellular and neuropathological consequences of severe injury of adult human brain tissue in vitro. The in vitro injuries caused by resection (interruption of the circulation) and aggravated by the preparation of slices (severed neuronal and glial processes and blood vessels) reflect the reaction of human brain tissue to severe injury. We investigated this process using immunocytochemical markers, reverse transcriptase quantitative polymerase chain reaction and Western blot analysis. Essential features were rapid shrinkage of neurons, loss of neuronal marker expression and proliferation of reactive cells that expressed Nestin and Vimentin. Also, microglia generally responded strongly, whereas the response of glial fibrillary acidic protein-positive astrocytes appeared to be more variable. Importantly, some reactive cells also expressed both microglia and astrocytic markers, thus confounding their origin. Comparison with post-mortem human brain tissue obtained at rapid autopsies suggested that the reactive process is not a consequence of epilepsy.
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Affiliation(s)
- Ronald W H Verwer
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, The Netherlands
| | - Arja A Sluiter
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, The Netherlands
| | - Rawien A Balesar
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, The Netherlands
| | - Johannes C Baaijen
- Department of Neurosurgery, VU University Medical Center, Amsterdam, The Netherlands
| | | | - Dave Speijer
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Yichen Li
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, The Netherlands
| | - Dick F Swaab
- Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, The Netherlands
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